bims-tucedo Biomed News
on Tumor cell dormancy
Issue of 2022–02–13
35 papers selected by
Isabel Puig Borreil, Vall d’Hebron Institute of Oncology



  1. Cancer Res. 2022 Feb 11. pii: canres.2062.2021. [Epub ahead of print]
      Despite being the leading cause of cancer deaths, metastasis remains a poorly understood process. To identify novel regulators of metastasis in melanoma, we performed a large-scale RNA-sequencing screen of 48 samples from patient-derived xenograft (PDX) subcutaneous melanomas and their associated metastases. In comparison to primary tumors, expression of glycolytic genes was frequently decreased in metastases while expression of some TCA cycle genes was increased in metastases. Consistent with these transcriptional changes, melanoma metastases underwent a metabolic switch characterized by decreased levels of glycolytic metabolites and increased abundance of TCA cycle metabolites. A short isoform of glyceraldehye-3-phosphate dehydrogenase, spermatogenic (GAPDHS) lacking the N-terminal domain suppressed metastasis and regulated this metabolic switch. GAPDHS was downregulated in metastatic nodules from PDX models as well as in human patients. Overexpression of GAPDHS was sufficient to block melanoma metastasis, while its inhibition promoted metastasis, decreased glycolysis, and increased levels of certain TCA cycle metabolites and their derivatives including citrate, fumarate, malate, and aspartate. Isotope tracing studies indicated that GADPHS mediates this shift through changes in pyruvate carboxylase activity and aspartate synthesis, both metabolic pathways critical for cancer survival and metastasis. Together these data identify a short isoform of GAPDHS that limits melanoma metastasis and regulates central carbon metabolism.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-2062
  2. Cancer Discov. 2022 Feb 11.
      A pan-cancer analysis reveals associations between genomic alterations and metastatic patterns.
    DOI:  https://doi.org/10.1158/2159-8290.CD-RW2022-023
  3. Cancer Res. 2022 Feb 11. pii: canres.3062.2021. [Epub ahead of print]
      Targeting cyclin-dependent kinases 4 and 6 (CDK4/6) is a successful therapeutic approach against breast and other solid tumors. Inhibition of CDK4/6 halts cell cycle progression and promotes antitumor immunity. However, the mechanisms underlying the antitumor activity of CDK4/6 inhibitors are not fully understood. We found that CDK4/6 bind and phosphorylate the p53 family member p73 at threonine 86, which sequesters p73 in the cytoplasm. Inhibition of CDK4/6 led to dephosphorylation and nuclear translocation of p73, which transcriptionally activated death receptor 5 (DR5), a cytokine receptor and key component of the extrinsic apoptotic pathway. p73-mediated induction of DR5 by CDK4/6 inhibitors promoted immunogenic cell death (ICD) of cancer cells. Deletion of DR5 in cancer cells in vitro and in vivo abrogated the potentiating effects of CDK4/6 inhibitors on immune cytokine TNF-related apoptosis-inducing ligand (TRAIL), 5-fluorouracil (5-FU) chemotherapy, and anti-PD-1 immunotherapy. Together, these results reveal a previously unrecognized consequence of CDK4/6 inhibition, which may be critical for potentiating the killing and immunogenic effects on cancer cells.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-3062
  4. Cancer Res. 2022 Feb 08. pii: canres.0914.2021. [Epub ahead of print]
      Lactate is an abundant oncometabolite in the tumor environment. In prostate cancer (PCa), cancer-associated fibroblasts are major contributors of secreted lactate, which can be taken up by cancer cells to sustain mitochondrial metabolism. However, how lactate impacts transcriptional regulation in tumors has yet to be fully elucidated. Here, we describe a mechanism by which CAF-secreted lactate is able to increase the expression of genes involved in lipid metabolism in PCa cells.This regulation enhanced intracellular lipid accumulation in lipid droplets (LD) and provided acetyl moieties for histone acetylation, establishing a regulatory loop between metabolites and epigenetic modification. Inhibition of this loop by targeting the bromodomain and extraterminal (BET) protein family of histone acetylation readers suppressed the expression of perilipin-2 (PLIN2), a crucial component of LDs, disrupting lactate-dependent lipid metabolic rewiring. Inhibition of this CAF-induced metabolic-epigenetic regulatory loop in vivo reduced growth and metastasis of prostate cancer cells, demonstrating its translational relevance as a therapeutic target in PCa. Clinically, PLIN2 expression was elevated in tumors with a higher Gleason grade and in castration resistant prostate cancer compared to primary PCa. Overall, these findings show that lactate has both a metabolic and an epigenetic role in promoting PCa progression.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-0914
  5. Oncogene. 2022 Feb 07.
      Non-small cell lung cancer (NSCLC) is a fatal disease, and its metastatic process is poorly understood. Although aberrant methylation is involved in tumor progression, the mechanisms underlying dynamic DNA methylation remain to be elucidated. It is significant to study the molecular mechanism of NSCLC metastasis and identify new biomarkers for NSCLC early diagnosis. Here, we performed MeDIP-seq and hMeDIP-seq analyses to detect the genes regulated by dynamic DNA methylation. Comparison of the 5mC and 5hmC sites revealed that the CD147 gene underwent active demethylation in NSCLC tissues compared with normal tissues, and this demethylation upregulated CD147 expression. Significantly high levels of CD147 expression and low levels of promoter methylation were observed in NSCLC tissues. Then, we identified the CD147 promoter as a target of KLF6, MeCP2, and DNMT3A. Treatment of cells with TGF-β triggered active demethylation involving loss of KLF6/MeCP2/DNMT3A and recruitment of Sp1, Tet1, TDG, and SMAD2/3 transcription complexes. A dCas9-SunTag-DNMAT3A-sgCD147-targeted methylation system was constructed to reverse CD147 expression. The targeted methylation system downregulated CD147 expression and inhibited NSCLC proliferation and metastasis in vitro and in vivo. Accordingly, we used cfDNA to detect the levels of CD147 methylation in NSCLC tissues and found that the CD147 methylation levels exhibited an inverse relationship with tumor size, lymphatic metastasis, and TNM stage. In conclusion, this study clarified the mechanism of active demethylation of CD147 and suggested that the targeted methylation of CD147 could inhibit NSCLC invasion and metastasis, providing a highly promising therapeutic target for NSCLC.
    DOI:  https://doi.org/10.1038/s41388-022-02213-0
  6. Mol Cancer. 2022 Feb 08. 21(1): 40
      
    Keywords:  ATP-binding cassette sub-family B member 1 (ABCB1); Multidrug resistance (MDR); OTS964; PDZ-binding kinase (PBK); T-LAK cell-originated protein kinase (TOPK)
    DOI:  https://doi.org/10.1186/s12943-022-01512-0
  7. Elife. 2022 Feb 08. pii: e73926. [Epub ahead of print]11
      15% of colorectal cancers (CRC) cells exhibit a mucin hypersecretory phenotype, which is suggested to provide resistance to immune surveillance and chemotherapy. We now formally show that colorectal cancer cells build a barrier to chemotherapeutics by increasing mucins' secretion. We show that low levels of KChIP3, a negative regulator of mucin secretion (Cantero-Recasens et al., 2018), is a risk factor for CRC patients' relapse in subset of untreated tumours. Our results also reveal that cells depleted of KChIP3 are four times more resistant (measured as cell viability and DNA damage) to chemotherapeutics 5-Fluorouracil plus Irinotecan (5-FU+iri.) compared to control cells, whereas KChIP3 overexpressing cells are 10 times more sensitive to killing by chemotherapeutics. Similar increase in tumour cell death is observed upon chemical inhibition of mucin secretion by the sodium/calcium exchanger (NCX) blockers (Mitrovic et al., 2013). Finally, sensitivity of CRC patient-derived organoids to 5-FU+iri increases 40-fold upon mucin secretion inhibition. Reducing mucin secretion thus provides a means to control chemoresistance of mucinous colorectal cancer cells and other mucinous tumours.
    Keywords:  cell biology; human
    DOI:  https://doi.org/10.7554/eLife.73926
  8. Cancer Res. 2022 Feb 07. pii: canres.1223.2021. [Epub ahead of print]
      Ovarian cancer (OC) is the deadliest gynecological cancer, and novel therapeutic options are crucial to improve overall survival. Here we provide evidence that impairment of oxidative phosphorylation (OXPHOS) can help control OC progression, and this benefit correlates with expression of the two mitochondrial master regulators PGC-1α and PGC-1β. In orthotopic patient-derived ovarian cancer xenografts (OC-PDX), concomitant high expression of PGC-1α and PGC-1β (PGC-1α/β) fostered a unique transcriptional signature, leading to increased mitochondrial abundance, enhanced tricarboxylic acid (TCA) cycling, and elevated cellular respiration that ultimately conferred vulnerability to OXPHOS inhibition. Treatment with the respiratory chain complex I inhibitor IACS-010759 caused mitochondrial swelling and ATP depletion that consequently delayed malignant progression and prolonged the lifespan of high-PGC-1α/β-expressing OC-PDX-bearing mice. Conversely, low-PGC-1α/β OC-PDX were not affected by IACS-010759, thus pinpointing a selective anti-tumor effect of OXPHOS inhibition. The clinical relevance of these findings was substantiated by analysis of ovarian cancer patient datasets, which showed that 25% of all cases displayed high PGC-1α/β expression along with an activated mitochondrial gene program. This study endorses the use of OXPHOS inhibitors to manage ovarian cancer and identifies the high expression of both PGC-1α and β as biomarkers to refine the selection of patients likely to benefit most from this therapy.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-1223
  9. Cancer Res. 2022 Feb 11. pii: canres.2218.2021. [Epub ahead of print]
      G9a and EZH2 are two histone methyltransferases commonly upregulated in several cancer types, yet the precise roles that these enzymes play cooperatively in cancer is unclear. We demonstrate here that frequent concurrent upregulation of both G9a and EZH2 occurs in several human tumors. These methyltransferases cooperatively repressed molecular pathways responsible for tumor cell death. In genetically distinct tumor subtypes, concomitant inhibition of G9a and EZH2 potently induced tumor cell death, highlighting the existence of tumor cell survival dependency at the epigenetic level. G9a and EZH2 synergistically repressed expression of genes involved in the induction of endoplasmic reticulum (ER) stress and the production of reactive oxygen species. IL24 was essential for the induction of tumor cell death and was identified as a common target of G9a and EZH2. Loss-of-function of G9a and EZH2 activated the IL24-ER stress axis and increased apoptosis in cancer cells while not affecting normal cells. These results indicate that G9a and EZH2 promotes the evasion of ER stress-mediated apoptosis by repressing IL24 transcription, therefore suggesting that their inhibition may represent a potential therapeutic strategy for solid cancers.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-2218
  10. Cancer Discov. 2022 Feb 11.
      A natural immune response was generated to somatic mutations in metastatic breast cancer patients.
    DOI:  https://doi.org/10.1158/2159-8290.CD-RW2022-025
  11. Oncogene. 2022 Feb 09.
      Discoidin domain receptor 1 (DDR1) is a member of the receptor tyrosine kinase family, and its ligand is collagen. Previous studies demonstrated that DDR1 is highly expressed in many tumors. However, its role in hepatocellular carcinoma (HCC) remains obscure. In this study, we found that DDR1 was upregulated in HCC tissues, and the expression of DDR1 in TNM stage II-IV was higher than that in TNM stage I in HCC tissues, and high DDR1 expression was associated with poor prognosis. Gene expression analysis showed that DDR1 target genes were functionally involved in HCC metastasis. DDR1 positively regulated the migration and invasion of HCC cells and promoted lung metastasis. Human Phospho-Kinase Array showed that DDR1 activated ERK/MAPK signaling pathway. Mechanically, DDR1 interacted with ARF6 and activated ARF6 through recruiting PSD4. The kinase activity of DDR1 was required for ARF6 activation and its role in metastasis. High expression of PSD4 was associated with poor prognosis in HCC. In summary, our findings indicate that DDR1 promotes HCC metastasis through collagen induced DDR1 signaling mediated PSD4/ARF6 signaling, suggesting that DDR1 and ARF6 may serve as novel prognostic biomarkers and therapeutic targets for metastatic HCC.
    DOI:  https://doi.org/10.1038/s41388-022-02212-1
  12. Oncogene. 2022 Feb 09.
      Molecular reprogramming of stromal microarchitecture by tumour-derived extracellular vesicles (EVs) is proposed to favour pre-metastatic niche formation. We elucidated the role of extravesicular tissue inhibitor of matrix metalloproteinase-1 (TIMP1EV) in pro-invasive extracellular matrix (ECM) remodelling of the liver microenvironment to aid tumour progression in colorectal cancer (CRC). Immunohistochemistry analysis revealed a high expression of stromal TIMP1 in the invasion front that was associated with poor progression-free survival in patients with colorectal liver metastases. Molecular analysis identified TIMP1EV enrichment in CRC-EVs as a major factor in the induction of TIMP1 upregulation in recipient fibroblasts. Mechanistically, we proved that EV-mediated TIMP1 upregulation in recipient fibroblasts induced ECM remodelling. This effect was recapitulated by human serum-derived EVs providing strong evidence that CRC release active EVs into the blood circulation of patients for the horizontal transfer of malignant traits to recipient cells. Moreover, EV-associated TIMP1 binds to HSP90AA, a heat-shock protein, and the inhibition of HSP90AA on human-derived serum EVs attenuates TIMP1EV-mediated ECM remodelling, rendering EV-associated TIMP1 a potential therapeutic target. Eventually, in accordance with REMARK guidelines, we demonstrated in three independent cohorts that EV-bound TIMP1 is a robust circulating biomarker for a non-invasive, preoperative risk stratification in patients with colorectal liver metastases.
    DOI:  https://doi.org/10.1038/s41388-022-02218-9
  13. Nat Commun. 2022 Feb 10. 13(1): 791
      Copy number alterations (CNAs) are pivotal genetic events in triple-negative breast cancer (TNBC). Here, our integrated copy number and transcriptome analysis of 302 TNBC patients reveals that gene alpha-endosulfine (ENSA) exhibits recurrent amplification at the 1q21.3 region and is highly expressed in TNBC. ENSA promotes tumor growth and indicates poor patient survival in TNBC. Mechanistically, we identify ENSA as an essential regulator of cholesterol biosynthesis in TNBC that upregulates the expression of sterol regulatory element-binding transcription factor 2 (SREBP2), a pivotal transcription factor in cholesterol biosynthesis. We confirm that ENSA can increase the level of p-STAT3 (Tyr705) and activated STAT3 binds to the promoter of SREBP2 to promote its transcription. Furthermore, we reveal the efficacy of STAT3 inhibitor Stattic in TNBC with high ENSA expression. In conclusion, the amplification of ENSA at the 1q21.3 region promotes TNBC progression and indicates sensitivity to STAT3 inhibitors.
    DOI:  https://doi.org/10.1038/s41467-022-28452-z
  14. Oncogene. 2022 Feb 11.
      Increasing studies have indicated that circular RNAs (circRNAs) play pivotal roles in various cancers. Here, we aimed to explore the roles of circRNAs in breast cancer. We identified a novel circRNA circKDM4B (hsa_circ_0002926) by whole-transcriptome sequencing and validated this by Real-time quantitative polymerase chain reaction (RT-qPCR) and Sanger sequencing. It was significantly decreased in breast cancer tissues compared with adjacent non-tumor tissues. Furthermore, circKDM4B, which is mainly localized in the cytoplasm, was more resistant to actinomycin D or ribonuclease R than its linear transcript KDM4B. In addition, the overexpression of circKDM4B inhibited cell migration and invasion in vitro, while knockdown of circKDM4B induced the opposite effects. In vivo, circKDM4B suppressed tumor growth and metastasis. Additionally, circKDM4B inhibited migration and tube formation of human umbilical vein endothelial cells (HUVECs) in vitro and angiogenesis in vivo. Mechanically, circKDM4B sponged miR-675 to upregulate the expression of NEDD4-like E3 ubiquitin protein ligase (NEDD4L), which catalyzes ubiquitination of PI3KCA, thereby inhibiting PI3K/AKT and VEGFA secretion. Collectively, these findings uncovered the tumor-suppressor role of circKDM4B in breast cancer, especially in angiogenesis and tumor metastasis, indicating that circKDM4B could be a potential therapeutic target for breast cancer progression.
    DOI:  https://doi.org/10.1038/s41388-022-02232-x
  15. Trends Cancer. 2022 Feb 03. pii: S2405-8033(22)00015-2. [Epub ahead of print]
      The host immune response is a potent defense mechanism against cancer development and progression. To survive, cancer cells must develop mechanisms to evade the immune response. Based on this knowledge, a series of new therapies collectively referred to as immunotherapies have been developed and translated to the clinic for treating cancer patients. Although some cancer subtypes have shown strong clinical responses, including curative outcomes in some patients, immunotherapies have not worked as desired for some subtypes and forms of cancers. We provide an overview of the transcriptional mechanisms that drive the response and resistance to immunotherapies. We also discuss possible interventions to enhance the outcomes of immunotherapies by targeting dysregulated transcriptional networks in cancer cells.
    Keywords:  epigenetics; gene regulation; immunotherapy; transcription
    DOI:  https://doi.org/10.1016/j.trecan.2022.01.008
  16. Cancer Res. 2022 Feb 07. pii: canres.1807.2021. [Epub ahead of print]
      Wnt signaling driven by genomic alterations in genes including APC and CTNNB, which encodes β-catenin, have been implicated in prostate cancer (PC) development and progression to metastatic castration-resistant PC (mCRPC). However, nongenomic drivers and downstream effectors of Wnt signaling in PC and the therapeutic potential of targeting this pathway in PC have not been fully established. Here we analyzed Wnt/β-catenin signaling in PC and identified effectors distinct from those found in other tissues, including AHR and RUNX1, which are linked to stem cell maintenance, and ROR1, a noncanonical Wnt5a co-receptor. Wnt/β-catenin signaling-mediated increases in ROR1 enhanced noncanonical responses to Wnt5a. Regarding upstream drivers, APC genomic loss, but not its epigenetic downregulation commonly observed in PC, was strongly associated with Wnt/β-catenin pathway activation in clinical samples. Tumor cell upregulation of the Wnt transporter Wntless (WLS) was strongly associated with Wnt/β-catenin pathway activity in primary PC but also associated with both canonical and noncanonical Wnt signaling in mCRPC. Immunohistochemistry confirmed tumor cell WLS expression in primary PC and mCRPC, and patient-derived PC xenografts expressing WLS were responsive to treatment with Wnt synthesis inhibitor ECT-159. These findings reveal that Wnt/β-catenin signaling in PC drives stem cell maintenance and invasion and primes for noncanonical Wnt signaling through ROR1. They further show that autocrine Wnt production is a nongenomic driver of canonical and noncanonical Wnt signaling in PC, which can be targeted with Wnt synthesis inhibitors to suppress tumor growth.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-1807
  17. Proc Natl Acad Sci U S A. 2022 Feb 15. pii: e2112696119. [Epub ahead of print]119(7):
      Lysine-specific demethylase 6A (KDM6A), also named UTX, is frequently mutated in bladder cancer (BCa). Although known as a tumor suppressor, KDM6A's therapeutic potential in the metastasis of BCa remains elusive. It also remains difficult to fulfill the effective up-regulation of KDM6A levels in bladder tumor tissues in situ to verify its potential in treating BCa metastasis. Here, we report a mucoadhesive messenger RNA (mRNA) nanoparticle (NP) strategy for the intravesical delivery of KDM6A-mRNA in mice bearing orthotopic Kdm6a-null BCa and show evidence of KDM6A's therapeutic potential in inhibiting the metastasis of BCa. Through this mucoadhesive mRNA NP strategy, the exposure of KDM6A-mRNA to the in situ BCa tumors can be greatly prolonged for effective expression, and the penetration can be also enhanced by adhering to the bladder for sustained delivery. This mRNA NP strategy is also demonstrated to be effective for combination cancer therapy with other clinically approved drugs (e.g., elemene), which could further enhance therapeutic outcomes. Our findings not only report intravesical delivery of mRNA via a mucoadhesive mRNA NP strategy but also provide the proof-of-concept for the usefulness of these mRNA NPs as tools in both mechanistic understanding and translational study of bladder-related diseases.
    Keywords:  KDM6A; bladder cancer; elemene; intravesical delivery; mRNA nanoparticles
    DOI:  https://doi.org/10.1073/pnas.2112696119
  18. Cancer Discov. 2022 Feb;12(2): 290-292
      For too long, assays exposing patient tumor cells to drugs to identify active therapies have been dismissed as ineffective. In this issue of Cancer Discovery, two groups independently demonstrate clinical utility of such functional precision medicine assays in hematologic malignancies.See related article by Kornauth et al., p. 372.See related article by Malani et al., p. 388.
    DOI:  https://doi.org/10.1158/2159-8290.CD-21-1498
  19. Mol Cancer. 2022 Feb 08. 21(1): 41
       BACKGROUND: PTEN is one of the most frequently mutated genes in human cancer. Although the roles of canonical PTEN protein and PTEN isoforms have been extensively explored, the current understanding of PTEN family members cannot fully illustrate the diversity of their roles in biological processes and tumor development. Notably, the function of noncoding RNAs arising from PTEN has been less elucidated.
    METHODS: We searched circBase and circInteractome to analyze the potential of PTEN for generating circRNAs. Then, Sanger sequencing, RNase R and Actinomycin D assays were used to verify the ring structure of circPTEN1. In situ hybridization and qRT-PCR were used to determine the level of circPTEN1 in peritumor and tumor tissues of colorectal cancer (CRC). Furthermore, functional experiments, including Transwell assay, 3D multicellular tumor spheroid invasion assay and metastasis models, were performed using circPTEN1 knockdown and overexpression cell lines in vitro and in vivo to investigate the effects of circPTEN1 on tumor metastasis in CRC. Mechanistically, luciferase reporter assay, fluorescence in situ hybridization, electrophoretic mobility shift assay, RNA immunoprecipitation, RNA pull-down and mass spectrometry were executed.
    RESULTS: We identified a circular RNA generated from the PTEN gene, designated circPTEN1, that is frequently downregulated in colorectal cancer, and decreased expression of circPTEN1 predicts poor survival. Low expression of circPTEN1 promotes metastasis in PDX models in vivo and accelerates cancer cell invasion in vitro, whereas overexpression of circPTEN1 reveals opposite roles. Mechanically, we found that circPTEN1 is capable of binding the MH2 domain of Smad4 to disrupt its physical interaction with Smad2/3, which reduces the formation and subsequent nucleus translocation of Smad complexes and consequently suppresses the expression of its downstream genes associated with epithelial-mesenchymal transition upon TGF-β stimulation. Furthermore, we found that eIF4A3 suppresses the cyclization of circPTEN1 by directly binding to the circPTEN1 flanking region.
    CONCLUSIONS: Our study uncovered a novel PTEN gene-generated circRNA with a tumor suppression function, and further revealed the mechanism of circPTEN1 in CRC metastasis mediated by TGF-β. The identification of circPTEN1 provides a new direction for PTEN investigation, and elucidation of circPTEN1/TGF-β/Smad signaling may pave the way for the development of a potential therapeutic strategy for the suppression of cancer progression.
    Keywords:  Colorectal cancer; PTEN; TGF-β/Smad signaling; Tumor metastasis; circRNA
    DOI:  https://doi.org/10.1186/s12943-022-01495-y
  20. Cancer Res. 2022 Feb 07. pii: canres.2161.2021. [Epub ahead of print]
      Chaperone-mediated autophagy (CMA) is a homeostatic process essential for the lysosomal degradation of a selected subset of the proteome. CMA activity directly depends on the levels of LAMP2A, a critical receptor for CMA substrate proteins at the lysosomal membrane. In glioblastoma (GBM), the most common and aggressive brain cancer in adulthood, high levels of LAMP2A in the tumor and tumor-associated pericytes have been linked to temozolomide resistance and tumor progression. However, the role of LAMP2A, and hence CMA, in any cancer stem cell type or in glioblastoma stem cells (GSC) remains unknown. In this work, we show that LAMP2A expression is enriched in patient-derived GSCs, and its depletion diminishes GSC-mediated tumorigenic activities. Conversely, overexpression of LAMP2A facilitates the acquisition of GSC properties. Proteomic and transcriptomic analysis of LAMP2A-depleted GSCs revealed reduced extracellular matrix (ECM) interaction effectors in both analyses. Moreover, pathways related to mitochondrial metabolism and the immune system were differentially deregulated at the proteome level. Furthermore, clinical samples of GBM tissue presented with overexpression of LAMP2, which correlated with advanced glioma grade and poor overall survival. In conclusion, these results identify a novel role of CMA in directly regulating GSCs activity via multiple pathways at the proteome and transcriptome levels.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-2161
  21. Cancer Res. 2022 Feb 11. pii: canres.1331.2021. [Epub ahead of print]
      Although most breast cancer metastases in bone cause osteolytic lesions, the osteogenic niche has commonly been described as an initiator of early-stage bone colonization of disseminated cancer cells. Tumor cell-derived extracellular vesicles (EV) have been shown to determine the organotropism of cancer cells by transferring their cargo, such as nucleic acids and proteins, to resident cells at future metastatic sites and preparing a favorable premetastatic niche. Runt-related transcription factor 2 (RUNX2) and its regulated genes have been shown to facilitate the acquisition of osteomimetic features and enhance the bone metastatic potential of breast cancer cells. In this study, we present in vivo and in vitro evidence to clarify the role of EVs released by breast cancer cells with high RUNX2 expression in the education of osteoblasts to form an osteogenic premetastatic niche. Furthermore, different extracellular vesicular proteins were identified that mediate events subsequent to the specific recognition of tumor-derived EVs by osteoblasts (CDH11) and the induction of the osteogenic premetastatic niche (ITGA5). CDH11high/ITGA5high EVs were demonstrated to be responsible for the formation of a premetastatic niche that facilitates RUNX2 high-expressing breast cancer cell colonization in bone, revealing a potential EV-based premetastatic niche blockage strategy.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-1331
  22. Oncogene. 2022 Feb 10.
      Analyzing different tumor regions by next generation sequencing allows the assessment of intratumor genetic heterogeneity (ITGH), a phenomenon that has been studied widely in some tumor types but has been less well explored in endometrial carcinoma (EC). In this study, we sought to characterize the spatial and temporal heterogeneity of 9 different ECs using whole-exome sequencing, and by performing targeted sequencing validation of the 42 primary tumor regions and 30 metastatic samples analyzed. In addition, copy number alterations of serous carcinomas were assessed by comparative genomic hybridization arrays. From the somatic mutations, identified by whole-exome sequencing, 532 were validated by targeted sequencing. Based on these data, the phylogenetic tree reconstructed for each case allowed us to establish the tumors' evolution and correlate this to tumor progression, prognosis, and the presence of recurrent disease. Moreover, we studied the genetic landscape of an ambiguous EC and the molecular profile obtained was used to guide the selection of a potential personalized therapy for this patient, which was subsequently validated by preclinical testing in patient-derived xenograft models. Overall, our study reveals the impact of analyzing different tumor regions to decipher the ITGH in ECs, which could help make the best treatment decision.
    DOI:  https://doi.org/10.1038/s41388-022-02221-0
  23. J Clin Oncol. 2022 Feb 10. JCO2101701
       PURPOSE: Currently, there are no robust biomarkers that predict immunotherapy outcomes in metastatic melanoma. We sought to build multivariable predictive models for response and survival to anti-programmed cell death protein 1 (anti-PD-1) monotherapy or in combination with anticytotoxic T-cell lymphocyte-4 (ipilimumab [IPI]; anti-PD-1 ± IPI) by including routine clinical data available at the point of treatment initiation.
    METHODS: One thousand six hundred forty-four patients with metastatic melanoma treated with anti-PD-1 ± IPI at 16 centers from Australia, the United States, and Europe were included. Demographics, disease characteristics, and baseline blood parameters were analyzed. The end points of this study were objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). The final predictive models for ORR, PFS, and OS were determined through penalized regression methodology (least absolute shrinkage and selection operator method) to select the most significant predictors for all three outcomes (discovery cohort, N = 633). Each model was validated internally and externally in two independent cohorts (validation-1 [N = 419] and validation-2 [N = 592]) and nomograms were created.
    RESULTS: The final model for predicting ORR (area under the curve [AUC] = 0.71) in immunotherapy-treated patients included the following clinical parameters: Eastern Cooperative Oncology Group Performance Status, presence/absence of liver and lung metastases, serum lactate dehydrogenase, blood neutrophil-lymphocyte ratio, therapy (monotherapy/combination), and line of treatment. The final predictive models for PFS (AUC = 0.68) and OS (AUC = 0.77) included the same variables as those in the ORR model (except for presence/absence of lung metastases), and included presence/absence of brain metastases and blood hemoglobin. Nomogram calculators were developed from the clinical models to predict outcomes for patients with metastatic melanoma treated with anti-PD-1 ± IPI.
    CONCLUSION: Newly developed combinations of routinely collected baseline clinical factors predict the response and survival outcomes of patients with metastatic melanoma treated with immunotherapy and may serve as valuable tools for clinical decision making.
    DOI:  https://doi.org/10.1200/JCO.21.01701
  24. Cancer Res. 2022 Feb 08. pii: canres.1382.2021. [Epub ahead of print]
      The combination of the synthetic TLR9 ligand CpG and agnostic OX40 antibody can trigger systemic anti-tumor immune responses upon co-injection into the tumor microenvironment, eradicating simultaneous untreated sites of metastatic disease. Here we explore the application of this in situ immunotherapy to the neoadjuvant setting. Current neoadjuvant checkpoint blockade therapy is delivered systemically, resulting in off-target adverse effects. In contrast, intratumoral immunotherapy minimizes the potential for toxicities and allows for greater development of combination therapies. In two metastatic solid tumor models, neoadjuvant intratumoral immunotherapy generated a local T cell antitumor response that then acted systemically to attack cancer throughout the body. In addition, the importance of timing between neoadjuvant immunotherapy and surgical resection was established, as well as the increased therapeutic power of adding systemic anti-PD1 antibody. The combination of local and systemic immunotherapy generated an additional survival benefit due to synergistic inhibitory effect on tumor-associated macrophages. These results provide a strong rationale for translating this neoadjuvant intratumoral immunotherapy to the clinical setting, especially in conjunction with established checkpoint inhibitors.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-21-1382
  25. Mol Cancer. 2022 Feb 10. 21(1): 43
       BACKGROUND: Identification of potential novel targets for reversing resistance to Epidermal Growth Factor Receptor (EGFR)-tyrosine kinase inhibitors (EGFR-TKIs) holds great promise for the treatment of relapsed lung adenocarcinoma (LUAD). In the present study, we aim to investigate the role of methyltransferase-like 7B (METTL7B) in inducing EGFR-TKIs resistance in LUAD and whether it could be a therapeutic target for reversing the resistance.
    METHODS: METTL7B-overexpressed LUAD cell lines, gefitinib and osimertinib-resistant Cell-Derived tumor Xenograft (CDX) and Patient-Derived tumor Xenograft (PDX) mouse models were employed to evaluate the role of METTL7B in TKIs resistance. Ultraperformance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS) was used to identify the metabolites regulated by METTL7B. Methylated RNA immunoprecipitation (MeRIP)-qPCR analysis was performed to measure the N6-methyladenosine (m6A) status of mRNA of METTL7B targeted genes. Gold nanocluster-assisted delivery of siRNA targeting METTL7B (GNC-siMETTL7B) was applied to evaluate the effect of METTL7B in TKIs resistance.
    RESULTS: Increased expression of METTL7B was found in TKIs-resistant LUAD cells and overexpression of METTL7B in LUAD cells induced TKIs resistance both in vitro and in vivo. Activated ROS-metabolism was identified in METTL7B-overexpressed LUAD cells, accompanied with upregulated protein level of GPX4, HMOX1 and SOD1 and their enzymatic activities. Globally elevated m6A levels were found in METTL7B-overexpressed LUAD cells, which was reduced by knock-down of METTL7B. METTL7B induced m6A modification of GPX4, HMOX1 and SOD1 mRNA. Knock-down of METTL7B by siRNA re-sensitized LUAD cells to gefitinib and osimertinib both in vitro and in vivo.
    CONCLUSIONS: This study uncovered a new critical link in METTL7B, glutathione metabolism and drug resistance. Our findings demonstrated that METTL7B inhibitors could be used for reversing TKIs resistance in LUAD patients.
    Keywords:  Glutathione metabolism; Lung adenocarcinomas; METTL7B; TKIs resistance; m6A modification
    DOI:  https://doi.org/10.1186/s12943-022-01519-7
  26. Mol Cancer. 2022 Feb 07. 21(1): 37
       PURPOSE: The overall response of cisplatin-based chemotherapy in bladder urothelial carcinoma (BUC) remains unsatisfactory due to the complex pathological subtypes, genomic difference, and drug resistance. The genes that associated with cisplatin resistance remain unclear. Herein, we aimed to identify the cisplatin resistance associated genes in BUC. EXPERIMENTAL DESIGN: The cytotoxicity of cisplatin was evaluated in six bladder cancer cell lines to compare their responses to cisplatin. The T24 cancer cells exhibited the lowest sensitivity to cisplatin and was therefore selected to explore the mechanisms of drug resistance. We performed genome-wide CRISPR screening in T24 cancer cells in vitro, and identified that the gene heterogeneous nuclear ribonucleoprotein U (HNRNPU) was the top candidate gene related to cisplatin resistance. Epigenetic and transcriptional profiles of HNRNPU-depleted cells after cisplatin treatment were analyzed to investigate the relationship between HNRNPU and cisplatin resistance. In vivo experiments were also performed to demonstrate the function of HNRNPU depletion in cisplatin sensitivity.
    RESULTS: Significant correlation was found between HNRNPU expression level and sensitivity to cisplatin in bladder cancer cell lines. In the high HNRNPU expressing T24 cancer cells, knockout of HNRNPU inhibited cell proliferation, invasion, and migration. In addition, loss of HNRNPU promoted apoptosis and S-phase arrest in the T24 cells treated with cisplatin. Data from The Cancer Genome Atlas (TCGA) demonstrated that HNRNPU expression was significantly higher in tumor tissues than in normal tissues. High HNRNPU level was negatively correlated with patient survival. Transcriptomic profiling analysis showed that knockout of HNRNPU enhanced cisplatin sensitivity by regulating DNA damage repair genes. Furthermore, it was found that HNRNPU regulates chemosensitivity by affecting the expression of neurofibromin 1 (NF1).
    CONCLUSIONS: Our study demonstrated that HNRNPU expression is associated with cisplatin sensitivity in bladder urothelial carcinoma cells. Inhibition of HNRNPU could be a potential therapy for cisplatin-resistant bladder cancer.
    Keywords:  Bladder urothelial carcinoma; Cisplatin; Genome-wide CRISPR screening; HNRNPU
    DOI:  https://doi.org/10.1186/s12943-022-01517-9
  27. Nat Cell Biol. 2022 Feb 10.
      Minimal residual disease that persists after chemotherapy is the most valuable prognostic marker for haematological malignancies and solid cancers. Unfortunately, our understanding of the resistance elicited in minimal residual disease is limited due to the rarity and heterogeneity of the residual cells. Here we generated 161,986 single-cell transcriptomes to analyse the dynamic changes of B-cell acute lymphoblastic leukaemia (B-ALL) at diagnosis, residual and relapse by combining single-cell RNA sequencing and B-cell-receptor sequencing. In contrast to those at diagnosis, the leukaemic cells at relapse tended to shift to poorly differentiated states, whereas the changes in the residual cells were more complicated. Differential analyses highlighted the activation of the hypoxia pathway in residual cells, resistant clones and B-ALL with MLL rearrangement. Both in vitro and in vivo models demonstrated that inhibition of the hypoxia pathway sensitized leukaemic cells to chemotherapy. This single-cell analysis of minimal residual disease opens up an avenue for the identification of potent treatment opportunities for B-ALL.
    DOI:  https://doi.org/10.1038/s41556-021-00814-7
  28. Sci Adv. 2022 Feb 11. 8(6): eabj1262
      Limited circulating tumor cells (CTCs) capturing efficiency and lack of regulation capability on CTC-supportive metastatic niches (MNs) are two main obstacles hampering the clinical translation of conventional liposomes for the treatment of metastatic breast cancers. Traditional delivery strategies, such as ligand modification and immune modulator co-encapsulation for nanocarriers, are inefficient and laborious. Here, a multifunctional Rg3 liposome loading with docetaxel (Rg3-Lp/DTX) was developed, in which Rg3 was proved to intersperse in the phospholipid bilayer and exposed its glycosyl on the liposome surface. Therefore, it exhibited much higher CTC-capturing efficiency via interaction with glucose transporter 1 (Glut1) overexpressed on CTCs. After reaching the lungs with CTCs, Rg3 inhibited the formation of MNs by reversing the immunosuppressive microenvironment. Together, Rg3-Lp/DTX exhibited excellent metastasis inhibition capacity by CTC ("seeds") neutralization and MN ("soil") inhibition. The strategy has great clinical translation prospects for antimetastasis treatment with enhanced therapeutic efficacy and simple preparation process.
    DOI:  https://doi.org/10.1126/sciadv.abj1262
  29. Nat Commun. 2022 Feb 09. 13(1): 774
      Genomic profiling can provide prognostic and predictive information to guide clinical care. Biomarkers that reliably predict patient response to chemotherapy and immune checkpoint inhibition in gastric cancer are lacking. In this retrospective analysis, we use our machine learning algorithm NTriPath to identify a gastric-cancer specific 32-gene signature. Using unsupervised clustering on expression levels of these 32 genes in tumors from 567 patients, we identify four molecular subtypes that are prognostic for survival. We then built a support vector machine with linear kernel to generate a risk score that is prognostic for five-year overall survival and validate the risk score using three independent datasets. We also find that the molecular subtypes predict response to adjuvant 5-fluorouracil and platinum therapy after gastrectomy and to immune checkpoint inhibitors in patients with metastatic or recurrent disease. In sum, we show that the 32-gene signature is a promising prognostic and predictive biomarker to guide the clinical care of gastric cancer patients and should be validated using large patient cohorts in a prospective manner.
    DOI:  https://doi.org/10.1038/s41467-022-28437-y
  30. Clin Cancer Res. 2022 Feb 09. pii: clincanres.0468.2020. [Epub ahead of print]
       PURPOSE: Proficient DNA repair by homologous recombination (HR) facilitates resistance to chemo-radiation in glioma stem cells (GSCs). We evaluated whether compromising HR by targeting HSP90, a molecular chaperone required for the function of key HR proteins, using onalespib, a long-acting, brain-penetrant HSP90 inhibitor, would sensitize high-grade gliomas to chemo-radiation in vitro and in vivo Experimental Design: The ability of onalespib to deplete HR client proteins, impair HR repair capacity, and sensitize GBM to chemo-radiation was evaluated in vitro in GSCs, and in vivo using zebrafish and mouse intracranial glioma xenograft models. The effects of HSP90 inhibition on the transcriptome and cytoplasmic proteins was assessed in GSCs and in ex vivo organotypic human glioma slice cultures.
    RESULTS: Treatment with onalespib depleted CHK1 and RAD51, two key proteins of the HR pathway, and attenuated HR repair, sensitizing GSCs to the combination of radiation and temozolomide (TMZ). HSP90 inhibition reprogrammed the transcriptome of GSCs and broadly altered expression of cytoplasmic proteins including known and novel client proteins relevant to GSCs. The combination of onalespib with radiation and TMZ extended survival in a zebra fish and a mouse xenograft model of GBM compared to the standard of care (radiation and TMZ) or onalespib with radiation.
    CONCLUSIONS: The results of this study demonstrate that targeting HR by HSP90 inhibition sensitizes GSCs to radiation and chemotherapy and extends survival in zebrafish and mouse intracranial models of GBM. These results provide a preclinical rationale for assessment of HSP90 inhibitors in combination with chemoradiation in GBM patients.
    DOI:  https://doi.org/10.1158/1078-0432.CCR-20-0468
  31. Elife. 2022 02 08. pii: e76632. [Epub ahead of print]11
      Screening for drugs that disrupt embryonic development in zebrafish can help identify treatments that suppress metastasis.
    Keywords:  Pizotifen; cancer; developmental biology; epiboly; gastrulation; metastasis; mice; phenotyping screening; zebrafish
    DOI:  https://doi.org/10.7554/eLife.76632
  32. Clin Cancer Res. 2022 Feb 11. pii: clincanres.1242.2021. [Epub ahead of print]
       PURPOSE: Cell-free DNA (cfDNA) offers a non-invasive approach to monitor cancer. Here we develop a method using whole-exome sequencing (WES) of cfDNA for simultaneously monitoring the full spectrum of cancer treatment outcomes, including MRD, recurrence, evolution, and second primary cancers.
    EXPERIMENTAL DESIGN: Three simulation datasets were generated from 26 cancer patients to benchmark the detection performance of MRD/recurrence and second primary cancers. For further validation, cfDNA samples (n=76) from cancer patients (n=35) with six different cancer types were used for performance validation during various treatments.
    RESULTS: We present a cfDNA-based cancer monitoring method, named cfTrack Taking advantage of the broad genome coverage of WES data, cfTrack can sensitively detect MRD and cancer recurrence by integrating signals across known clonal tumor mutations of a patient. In addition, cfTrack detects tumor evolution and second primary cancers by de novo identifying emerging tumor mutations. A series of machine learning and statistical denoising techniques are applied to enhance the detection power. On the simulation data,cfTrack achieved an average AUC of 99% on the validation dataset and 100% on the independent dataset in detecting recurrence in samples with tumor fractions {greater than or equal to}0.05%. In addition,cfTrack yielded an average AUC of 88% in detecting second primary cancers in samples with tumor fractions {greater than or equal to}0.2%. On real data, cfTrack accurately monitors tumor evolution during treatment, which cannot be accomplished by previous methods.
    CONCLUSION: Our results demonstrated that cfTrack can sensitively and specifically monitor the full spectrum of cancer treatment outcomes using exome-wide mutation analysis of cfDNA.
    DOI:  https://doi.org/10.1158/1078-0432.CCR-21-1242
  33. Oncogene. 2022 Feb 07.
      Trop-2 is a transmembrane signal transducer that is overexpressed in most human cancers, and drives malignant progression. To gain knowledge on the higher-order molecular mechanisms that drive Trop-2 signaling, we applied next-generation sequencing, proteomics, and high-resolution microscopy to models and primary cases of human colorectal cancer (CRC). We had previously shown that Trop-2 induces a Ca2+ signal. We reveal here that Trop-2 binds the cell membrane Na+/K+-ATPase, and that clustering of Trop-2 induces an intracellular Ca2+ rise followed by membrane translocation of PKCα, which in turn phosphorylates the Trop-2 cytoplasmic tail. This feed-forward signaling is promoted by the binding of Trop-2 to the PKCα membrane-anchor CD9. CRISPR-based inactivation of CD9 in CRC cells shows that CD9 is required by Trop-2 for recruiting PKCα and cofilin-1 to the cell membrane. This induces malignant progression through proteolytic cleavage of E-cadherin, remodeling of the β-actin cytoskeleton, and activation of Akt and ERK. The interaction between Trop-2 and CD9 was validated in vivo in murine models of CRC growth and invasion. Overexpression of the components of this Trop-2-driven super-complex significantly worsened disease-free and overall survival of CRC patients, supporting a pivotal relevance in CRC malignant progression. Our findings demonstrate a previously unsuspected layer of cancer growth regulation, which is dormant in normal tissues, and is activated by Trop-2 in cancer cells.
    DOI:  https://doi.org/10.1038/s41388-022-02220-1
  34. Oncogene. 2022 Feb 11.
      Colorectal cancer liver metastasis (CRLM) is the leading cause of colorectal cancer-related deaths and remains a clinical challenge. Enhancement of glucose uptake is involved in CRLM; however, whether long noncoding RNAs (lncRNAs) participate in these molecular events remains largely unclear. Here, we report an lncRNA, GAL (glucose transporter 1 (GLUT1) associated lncRNA), that was upregulated in CRLM tissues compared with primary colorectal cancer (CRC) tissues or matched normal tissues and was associated with the overall survival rates of CRLM patients. Functionally, GAL served as an oncogene because it promoted CRC cell migration and invasion in vitro and enhanced the ability of CRC cells to metastasize from the intestine to the liver in vivo. Mechanistically, GAL interacted with the GLUT1 protein to increase GLUT1 SUMOylation, inhibiting the effect of the ubiquitin-proteasome system on the GLUT1 protein. GLUT1-knockout (-/+) repressed the GAL-mediated increase in CRC cell uptake of glucose, migrate, and invade in vitro, as well as metastasis from the intestine to the liver in vivo, and enforced expression of GLUT1 rescued GAL knockout-induced biological functions in CRC cells. Taken together, our findings demonstrated that GAL promotes CRLM by stabilizing GLUT1, suggesting that the GAL-GLUT1 complex may act as a potential therapeutic target for CRLM.
    DOI:  https://doi.org/10.1038/s41388-022-02230-z