bims-cagime Biomed News
on Cancer, aging and metabolism
Issue of 2022‒03‒20
23 papers selected by
Kıvanç Görgülü
Technical University of Munich


  1. Visc Med. 2022 Feb;38(1): 37-41
      Background: The advent of next-generation sequencing technologies has enabled the identification of molecular subtypes of pancreatic ductal adenocarcinoma (PDAC) with different biological traits and clinically targetable features.Summary: Although current chemotherapy trials are currently exploiting this knowledge, these molecular subtypes have not yet sufficiently caught the attention of surgeons. In fact, integration of these molecular subtypes into the timing of surgery can in theory improve patient outcome. Here, we present the molecular subtypes of PDAC from the surgeon's perspective and a clinically applicable algorithm that integrates the molecular subtyping of PDAC preoperatively into the decision of primary surgery versus neoadjuvant therapy. Furthermore, we point out the potential of "tailored" (in addition to conventional) neoadjuvant treatment for exploiting the molecular subtypes of PDAC.
    Key Messages: We believe that for surgeons, the preoperative knowledge on the subtype of PDAC can properly guide in deciding between upfront surgery versus neoadjuvant treatment for improving patient outcome.
    Keywords:  Molecular subtype; Neoadjuvant surgery; Pancreatic cancer; Primary
    DOI:  https://doi.org/10.1159/000519755
  2. Trends Cancer. 2022 Mar 14. pii: S2405-8033(22)00043-7. [Epub ahead of print]
      The 3D architecture of tissues bearing tumors impacts on the mechanical microenvironment of cancer, the accessibility of stromal cells, and the routes of invasion. A myriad of intrinsic and extrinsic forces exerted by the cancer cells, the host tissue, and the molecular and cellular microenvironment modulate the morphology of the tumor and its malignant potential through mechanical, biochemical, genetic, and epigenetic cues. Recent studies have investigated how tissue architecture influences cancer biology from tumor initiation and progression to distant metastatic seeding and response to therapy. With a focus on carcinoma, the most common type of cancer, this review discusses the latest discoveries on how tumor architecture is built and how tissue morphology affects the biology and progression of cancer cells.
    Keywords:  mechanics; tissue architecture; tumor progression; tumorigenesis
    DOI:  https://doi.org/10.1016/j.trecan.2022.02.007
  3. Nat Cell Biol. 2022 Mar;24(3): 316-326
      Proliferation is a fundamental trait of cancer cells, but its properties and spatial organization in tumours are poorly characterized. Here we use highly multiplexed tissue imaging to perform single-cell quantification of cell cycle regulators and then develop robust, multivariate, proliferation metrics. Across diverse cancers, proliferative architecture is organized at two spatial scales: large domains, and smaller niches enriched for specific immune lineages. Some tumour cells express cell cycle regulators in the (canonical) patterns expected of freely growing cells, a phenomenon we refer to as 'cell cycle coherence'. By contrast, the cell cycles of other tumour cell populations are skewed towards specific phases or exhibit non-canonical (incoherent) marker combinations. Coherence varies across space, with changes in oncogene activity and therapeutic intervention, and is associated with aggressive tumour behaviour. Thus, multivariate measures from high-plex tissue images capture clinically significant features of cancer proliferation, a fundamental step in enabling more precise use of anti-cancer therapies.
    DOI:  https://doi.org/10.1038/s41556-022-00860-9
  4. Science. 2022 Mar 18. 375(6586): eaay9040
      Survival improves when cancer is detected early. However, ~50% of cancers are at an advanced stage when diagnosed. Early detection of cancer or precancerous change allows early intervention to try to slow or prevent cancer development and lethality. To achieve early detection of all cancers, numerous challenges must be overcome. It is vital to better understand who is at greatest risk of developing cancer. We also need to elucidate the biology and trajectory of precancer and early cancer to identify consequential disease that requires intervention. Insights must be translated into sensitive and specific early detection technologies and be appropriately evaluated to support practical clinical implementation. Interdisciplinary collaboration is key; advances in technology and biological understanding highlight that it is time to accelerate early detection research and transform cancer survival.
    DOI:  https://doi.org/10.1126/science.aay9040
  5. Nat Rev Drug Discov. 2022 Mar 15.
      Immune checkpoint inhibitors (ICIs) have revolutionized the clinical management of multiple tumours. However, only a few patients respond to ICIs, which has generated considerable interest in the identification of resistance mechanisms. One such mechanism reflects the ability of various oncogenic pathways, as well as stress response pathways required for the survival of transformed cells (a situation commonly referred to as 'non-oncogene addiction'), to support tumour progression not only by providing malignant cells with survival and/or proliferation advantages, but also by establishing immunologically 'cold' tumour microenvironments (TMEs). Thus, both oncogene and non-oncogene addiction stand out as promising targets to robustly inflame the TME and potentially enable superior responses to ICIs.
    DOI:  https://doi.org/10.1038/s41573-022-00415-5
  6. Am J Physiol Gastrointest Liver Physiol. 2022 Mar 16.
      Proper mitochondrial function and adequate cellular ATP are necessary for normal pancreatic protein synthesis and sorting, maintenance of intracellular organelles and enzyme secretion. Inorganic phosphate is required for generating ATP and its limited availability may lead to reduced ATP production causing impaired Ca2+ handling, defective autophagy, zymogen activation, and necrosis - all features of acute pancreatitis. We hypothesized that reduced dietary phosphate leads to hypophosphatemia and exacerbates pancreatitis severity of multiple causes. We observed that mice fed a low phosphate diet prior to induction of pancreatitis by either repeated caerulein administration or pancreatic duct injection as a model of pressure-induced pancreatitis developed hypophosphatemia and exhibited more severe pancreatitis than normophosphatemic mice. Pancreatitis severity was significantly reduced in mice treated with phosphate. In vitro modeling of secretagogue- and pressure-induced pancreatic injury was evaluated in isolated pancreatic acini using cholecystokinin and the mechanoreceptor Piezo1 agonist, Yoda1, under low and normal phosphate conditions. Isolated pancreatic acini were more sensitive to cholecystokinin- and Yoda1-induced acinar cell damage and mitochondrial dysfunction under low phosphate conditions and improved following phosphate supplementation. Importantly, even mice on a normal phosphate diet exhibited less severe pancreatitis when treated with supplemental phosphate. Thus, hypophosphatemia sensitizes animals to pancreatitis and phosphate supplementation reduces pancreatitis severity. These appear to be direct effects of phosphate on acinar cells through restoration of mitochondrial function. We propose that phosphate administration may be useful in the treatment of acute pancreatitis.
    Keywords:  Piezo1; animal model; caerulein; mitochondria; pancreatography
    DOI:  https://doi.org/10.1152/ajpgi.00022.2022
  7. Elife. 2022 Mar 18. pii: e77749. [Epub ahead of print]11
      Many of the features associated with senescence appear steadily over time before cells stop dividing.
    Keywords:  chromosomes; epithelial to mesenchymal transition; gene expression; genetics; genomics; human; replicative senescence; senescence
    DOI:  https://doi.org/10.7554/eLife.77749
  8. Nat Metab. 2022 Mar 14.
      The relationships between metabolic rate, body temperature (Tb), body composition and ageing are complex, and not fully resolved. In particular, Tb and metabolic rate often change in parallel, making disentangling their effects difficult. Here we show that in both sexes of mice and hamsters exposure to a temperature of 32.5 °C leads to a reduced lifespan, coincident with lowered metabolic rate and elevated Tb with no change in body composition. We exploit the unique situation that when small mammals are exposed to hot ambient temperatures their Tb goes up, at the same time that their metabolic rate goes down, allowing us to experimentally separate the impacts of Tb and metabolic rate on lifespan. The impact of ambient temperature on lifespan can be reversed by exposing the animals to elevated heat loss by forced convection, which reverses the effect on Tb but does not affect metabolic rate, demonstrating the causal effect of Tb on lifespan under laboratory conditions for these models. The impact of manipulations such as calorie restriction that increase lifespan may be mediated via effects on Tb, and measuring Tb may be a useful screening tool for putative therapeutics to extend the human lifespan.
    DOI:  https://doi.org/10.1038/s42255-022-00545-5
  9. Autophagy. 2022 Mar 16. 1-15
      Ethanol increases hepatic mitophagy driven by unknown mechanisms. Type 1 mitophagy sequesters polarized mitochondria for nutrient recovery and cytoplasmic remodeling. In Type 2, mitochondrial depolarization (mtDepo) initiates mitophagy to remove the damaged organelles. Previously, we showed that acute ethanol administration produces reversible hepatic mtDepo. Here, we tested the hypothesis that ethanol-induced mtDepo initiates Type 2 mitophagy. GFP-LC3 transgenic mice were gavaged with ethanol (2-6 g/kg) with and without pre-treatment with agents that decrease or increase mtDepo-Alda-1, tacrolimus, or disulfiram. Without ethanol, virtually all hepatocytes contained polarized mitochondria with infrequent autophagic GFP-LC3 puncta visualized by intravital microscopy. At ~4 h after ethanol treatment, mtDepo occurred in an all-or-none fashion within individual hepatocytes, which increased dose dependently. GFP-LC3 puncta increased in parallel, predominantly in hepatocytes with mtDepo. Mitochondrial PINK1 and PRKN/parkin also increased. After covalent labeling of mitochondria with MitoTracker Red (MTR), GFP-LC3 puncta encircled MTR-labeled mitochondria after ethanol treatment, directly demonstrating mitophagy. GFP-LC3 puncta did not associate with fat droplets visualized with BODIPY558/568, indicating that increased autophagy was not due to lipophagy. Before ethanol administration, rhodamine-dextran (RhDex)-labeled lysosomes showed little association with GFP-LC3. After ethanol treatment, TFEB (transcription factor EB) translocated to nuclei, and lysosomal mass increased. Many GFP-LC3 puncta merged with RhDex-labeled lysosomes, showing autophagosomal processing into lysosomes. After ethanol treatment, disulfiram increased, whereas Alda-1 and tacrolimus decreased mtDepo, and mitophagy changed proportionately. In conclusion, mtDepo after acute ethanol treatment induces mitophagic sequestration and subsequent lysosomal processing.Abbreviations : AcAld, acetaldehyde; ADH, alcohol dehydrogenase; ALDH, aldehyde dehydrogenase; ALD, alcoholic liver disease; Alda-1, N-(1,3-benzodioxol-5-ylmethyl)-2,6-dichlorobenzamide; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; GFP, green fluorescent protein; LAMP1, lysosomal-associated membrane protein 1; LMNB1, lamin B1; MAA, malondialdehyde-acetaldehyde adducts; MAP1LC3/LC3, microtubule-associated protein 1 light chain 3; MPT, mitochondrial permeability transition; mtDAMPS, mitochondrial damage-associated molecular patterns; mtDepo, mitochondrial depolarization; mtDNA, mitochondrial DNA; MTR, MitoTracker Red; PI, propidium iodide; PINK1, PTEN induced putative kinase 1; PRKN, parkin; RhDex, rhodamine dextran; TFEB, transcription factor EB; Tg, transgenic; TMRM, tetramethylrhodamine methylester; TOMM20, translocase of outer mitochondrial membrane 20; VDAC, voltage-dependent anion channel.
    Keywords:  Acetaldehyde; Alda-1; alcoholic liver disease; mitochondrial depolarization; mitophagy; tacrolimus
    DOI:  https://doi.org/10.1080/15548627.2022.2046457
  10. Adv Drug Deliv Rev. 2022 Mar 09. pii: S0169-409X(22)00071-0. [Epub ahead of print]184 114181
      Major progress in the understanding and treatment of cancer have tremendously improved our knowledge of this complex disease and improved the length and quality of patients' lives. Still, major challenges remain, in particular with respect to cancer metastasis which still escapes effective treatment and remains responsible for 90% of cancer related deaths. In recent years, the advances in cancer cell biology, oncology and tissue engineering converged into the engineered human tissue models of cancer that are increasingly recapitulating many aspects of cancer progression and response to drugs, in a patient-specific context. The complexity and biological fidelity of these models, as well as the specific questions they aim to investigate, vary in a very broad range. When selecting and designing these experimental models, the fundamental question is "how simple is complex enough" to accomplish a specific goal of cancer research. Here we review the state of the art in developing and using the human tissue models in cancer research and developmental drug screening. We describe the main classes of models providing different levels of biological fidelity and complexity, discuss their advantages and limitations, and propose a framework for designing an appropriate model for a given study. We close by outlining some of the current needs, opportunities and challenges in this rapidly evolving field.
    Keywords:  Cancer; Drug development; Metastasis; Organoids; Organs-on-a-chip; Precision medicine; Tissue engineering
    DOI:  https://doi.org/10.1016/j.addr.2022.114181
  11. Cell Oncol (Dordr). 2022 Mar 15.
      Pancreatic ductal metaplasia (PDM) is the transformation of potentially various types of cells in the pancreas into ductal or ductal-like cells, which eventually replace the existing differentiated somatic cell type(s). PDM is usually triggered by and manifests its ability to adapt to environmental stimuli and genetic insults. The development of PDM to atypical hyperplasia or dysplasia is an important risk factor for pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma (PDA). Recent studies using genetically engineered mouse models, cell lineage tracing, single-cell sequencing and others have unraveled novel cellular and molecular insights in PDM formation and evolution. Those novel findings help better understand the cellular origins and functional significance of PDM and its regulation at cellular and molecular levels. Given that PDM represents the earliest pathological changes in PDA initiation and development, translational studies are beginning to define PDM-associated cell and molecular biomarkers that can be used to screen and detect early PDA and to enable its effective intervention, thereby truly and significantly reducing the dreadful mortality rate of PDA. This review will describe recent advances in the understanding of PDM biology with a focus on its underlying cellular and molecular mechanisms, and in biomarker discovery with clinical implications for the management of pancreatic regeneration and tumorigenesis.
    Keywords:  Cellular origin; Inflammation; Metaplasia; Pancreas; Regeneration; Stem cells; Transdifferentiation; Tumorigenesis
    DOI:  https://doi.org/10.1007/s13402-022-00664-x
  12. Annu Rev Anal Chem (Palo Alto Calif). 2022 Feb 18.
      Cellular organelles are highly specialized compartments with distinct functions. With the increasing resolution of detection methods, it is becoming clearer that same organelles may have different functions or properties not only within different cell populations of a tissue but also within the same cell. Dysfunction or altered function affects the organelle itself and may also lead to malignancies or undesirable cell death. To understand cellular function or dysfunction, it is therefore necessary to analyze cellular components at the single-organelle level. Here, we review the recent advances in analyzing cellular function at single-organelle resolution using high-parameter flow cytometry or multicolor confocal microscopy. We focus on the analysis of mitochondria, as they are organelles at the crossroads of various cellular signaling pathways and functions. However, most of the applied methods/technologies are transferable to any other organelle, such as the endoplasmic reticulum, lysosomes, or peroxisomes. Expected final online publication date for the Annual Review of Analytical Chemistry Volume 15 is June 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
    DOI:  https://doi.org/10.1146/annurev-anchem-061020-111722
  13. Nat Protoc. 2022 Mar 14.
      Genetically engineered mouse models (GEMMs) transformed the study of organismal disease phenotypes but are limited by their lengthy generation in embryonic stem cells. Here, we describe methods for rapid and scalable genome engineering in somatic cells of the liver and pancreas through delivery of CRISPR components into living mice. We introduce the spectrum of genetic tools, delineate viral and nonviral CRISPR delivery strategies and describe a series of applications, ranging from gene editing and cancer modeling to chromosome engineering or CRISPR multiplexing and its spatio-temporal control. Beyond experimental design and execution, the protocol describes quantification of genetic and functional editing outcomes, including sequencing approaches, data analysis and interpretation. Compared to traditional knockout mice, somatic GEMMs face an increased risk for mouse-to-mouse variability because of the higher experimental demands of the procedures. The robust protocols described here will help unleash the full potential of somatic genome manipulation. Depending on the delivery method and envisaged application, the protocol takes 3-5 weeks.
    DOI:  https://doi.org/10.1038/s41596-021-00677-0
  14. Elife. 2022 Mar 18. pii: e67190. [Epub ahead of print]11
      A rare but severe complication of curative-intent radiation therapy is the induction of second primary cancers. These cancers preferentially develop not inside the planning target volume (PTV) but around, over several centimeters, after a latency period of 1-40 years. We show here that normal human or mouse dermal fibroblasts submitted to the out-of-field dose scattering at the margin of a PTV receiving a mimicked patient's treatment do not die but enter in a long-lived senescent state resulting from the accumulation of unrepaired DNA single-strand breaks, in the almost absence of double-strand breaks. Importantly, a few of these senescent cells systematically and spontaneously escape from the cell cycle arrest after a while to generate daughter cells harboring mutations and invasive capacities. These findings highlight single-strand break-induced senescence as the mechanism of second primary cancer initiation, with clinically relevant spatiotemporal specificities. Senescence being pharmacologically targetable, they open the avenue for second primary cancer prevention.
    Keywords:  cancer biology; cell biology; dna double-strand breaks; dna repair; dna single-strand breaks; normal human dermal fibroblasts; parp; radiotherapy; sarcoma; second primary cancer; senescence
    DOI:  https://doi.org/10.7554/eLife.67190
  15. Methods Mol Biol. 2022 ;2474 83-89
      Autophagy plays an important role in maintaining cellular homeostasis. Defects in autophagy have been linked to various human diseases, such as cancer, neurodegenerative diseases, and cardiovascular diseases. Therefore, it is useful to develop an assay that can measure the functions of autophagy and also be used to identify autophagy modulators by screening a large number of compounds. This chapter describes a cell-based high content green fluorescent protein (GFP)-LC3 assay using mouse embryonic fibroblasts (MEF) stably expressing GFP-LC3.
    Keywords:  Autophagy; GFP-LC3 cell line; High-content assay
    DOI:  https://doi.org/10.1007/978-1-0716-2213-1_9
  16. SLAS Discov. 2022 Mar 11. pii: S2472-5552(22)12517-7. [Epub ahead of print]
      KRAS is one of the most heavily mutated oncogenes in cancer and targeting mutant KRAS with drugs has proven difficult. However, recent FDA approval of the KRAS G12C selective inhibitor sotorasib (AMG-510), has breathed new life into the drive to develop mutant KRAS inhibitors. In an effort to study RAS inhibitors in cells and identify new compounds that inhibit Ras signaling, western blotting and ELISA assays are commonly used. These traditional immunoassays are tedious, require multiple washing steps, and are not easily adaptable to a high throughput screening (HTS) format. To overcome these limitations, we applied Lumit immunoassay technology to analyze RAS signaling pathway activation and inhibition through the detection of phosphorylated ERK. The assay we developed was used to rank order potencies of allele specific inhibitors within cell lines harboring various activating KRAS mutations. An inhibition profile was obtained indicating various potencies and selectivity of the inhibitors, including MRTX-1133, which was shown to be highly potent against KRAS G12D signaling. MRTX-1133 had approximately 40 and 400 times less inhibitory potency against G12C and G12V mutant KRAS, respectively, while no inhibition of WT KRAS was observed. The potency of PROTAC compound LC-2 targeting selective degradation of KRAS G12C was also tested using the Lumit pERK immunoassay, and a maximal decrease in RAS signaling was achieved. Lumit immunoassays provide a rapid, homogeneous platform for detecting signaling pathway activation and inhibition. Our results demonstrate that this bioluminescent technology can streamline the analysis of signaling pathways of interest, such as RAS-dependent pathways, and be used to identify much needed inhibitors. The results further imply that similar assay designs could be applied to other signaling pathway nodes.
    Keywords:  Bioluminescence; Immunoassay; KRAS mutants; MAPK signaling; Phospho ERK
    DOI:  https://doi.org/10.1016/j.slasd.2022.03.001
  17. Elife. 2022 Mar 17. pii: e71282. [Epub ahead of print]11
      The loss of skeletal muscle function with age, known as sarcopenia, significantly reduces independence and quality of life and can have significant metabolic consequences. Although exercise is effective in treating sarcopenia it is not always a viable option clinically, and currently there are no pharmacological therapeutic interventions for sarcopenia. Here we show that chronic treatment with pan-adiponectin receptor agonist AdipoRon improved muscle function in male mice by a mechanism linked to skeletal muscle metabolism and tissue remodeling. In aged mice, 6 weeks of AdipoRon treatment improved skeletal muscle functional measures in vivo and ex vivo. Improvements were linked to changes in fiber type, including an enrichment of oxidative fibers, and an increase in mitochondrial activity. In young mice, 6 weeks of AdipoRon treatment improved contractile force and activated the energy sensing kinase AMPK and the mitochondrial regulator PGC-1a (peroxisome proliferator activated receptor gamma coactivator 1 alpha). In cultured cells, the AdipoRon induced stimulation of AMPK and PGC-1a was associated with increased mitochondrial membrane potential, reorganization of mitochondrial architecture, increased respiration, and increased ATP production. Furthermore, the ability of AdipoRon to stimulate AMPK and PGC1a was conserved in nonhuman primate cultured cells. These data show that AdipoRon is an effective agent for the prevention of sarcopenia in mice and indicate that its effects translate to primates, suggesting it may also be a suitable therapeutic for sarcopenia in clinical application.
    Keywords:  cell biology; mouse; rhesus macaque
    DOI:  https://doi.org/10.7554/eLife.71282
  18. J Cachexia Sarcopenia Muscle. 2022 Mar 19.
      BACKGROUND: Sarcopenic obesity is a highly prevalent disease with poor survival and ineffective medical interventions. Mitochondrial dysfunction is purported to be central in the pathogenesis of sarcopenic obesity by impairing both organelle biogenesis and quality control. We have previously identified that a mitochondrial-targeted furazano[3,4-b]pyrazine named BAM15 is orally available and selectively lowers respiratory coupling efficiency and protects against diet-induced obesity in mice. Here, we tested the hypothesis that mitochondrial uncoupling simultaneously attenuates loss of muscle function and weight gain in a mouse model of sarcopenic obesity.METHODS: Eighty-week-old male C57BL/6J mice with obesity were randomized to 10 weeks of high fat diet (CTRL) or BAM15 (BAM15; 0.1% w/w in high fat diet) treatment. Body weight and food intake were measured weekly. Body composition, muscle function, energy expenditure, locomotor activity, and glucose tolerance were determined after treatment. Skeletal muscle was harvested and evaluated for histology, gene expression, protein signalling, and mitochondrial structure and function.
    RESULTS: BAM15 decreased body weight (54.0 ± 2.0 vs. 42.3 ± 1.3 g, P < 0.001) which was attributable to increased energy expenditure (10.1 ± 0.1 vs. 11.3 ± 0.4 kcal/day, P < 0.001). BAM15 increased muscle mass (52.7 ± 0.4 vs. 59.4 ± 1.0%, P < 0.001), strength (91.1 ± 1.3 vs. 124.9 ± 1.2 g, P < 0.0001), and locomotor activity (347.0 ± 14.4 vs. 432.7 ± 32.0 m, P < 0.001). Improvements in physical function were mediated in part by reductions in skeletal muscle inflammation (interleukin 6 and gp130, both P < 0.05), enhanced mitochondrial function, and improved endoplasmic reticulum homeostasis. Specifically, BAM15 activated mitochondrial quality control (PINK1-ubiquitin binding and LC3II, P < 0.01), increased mitochondrial activity (citrate synthase and complex II activity, all P < 0.05), restricted endoplasmic reticulum (ER) misfolding (decreased oligomer A11 insoluble/soluble ratio, P < 0.0001) while limiting ER stress (decreased PERK signalling, P < 0.0001), apoptotic signalling (decreased cytochrome C release and Caspase-3/9 activation, all P < 0.001), and muscle protein degradation (decreased 14-kDa actin fragment insoluble/soluble ratio, P < 0.001).
    CONCLUSIONS: Mitochondrial uncoupling by agents such as BAM15 may mitigate age-related decline in muscle mass and function by molecular and cellular bioenergetic adaptations that confer protection against sarcopenic obesity.
    Keywords:  Ageing; BAM15; Bioenergetics; Mitochondrial uncoupling; Obesity; Sarcopenia
    DOI:  https://doi.org/10.1002/jcsm.12982
  19. EMBO Mol Med. 2022 Mar 14. e15707
      Standard-of-care regimens for pancreatic ductal adenocarcinoma (PDAC) include a combination of chemotherapies, which are associated with toxicity and eventually tumor resistance. The lack of relevant tool to identify and evaluate new therapies in PDAC necessitates the search for a model, especially for cases with treatment resistance to standard of care. In the study from Peschke et al (2022), they describe a longitudinal platform to identify drug-induced vulnerabilities following standard-of-care chemotherapy treatment using patient-derived organoids (PDOs) providing an opportunity to predict therapeutic response and define new treatment vulnerability induced by standard of care. Previously, tumor resistance to chemotherapy has typically been described as selection for resistant tumor cell populations. However, Peschke et al (2022) demonstrated that PDAC cells seemed to acquire resistance not only through genetic changes, but also through modifications in cellular plasticity leading to gene expression and metabolism changes. Thus, the study supports this type of platform for the identification of new therapeutic targets following standard-of-care treatments in PDAC.
    DOI:  https://doi.org/10.15252/emmm.202215707
  20. Clin Cancer Res. 2022 Mar 18. pii: clincanres.3581.2021. [Epub ahead of print]
      PURPOSE: KRAS mutation (MT) is a major oncogenic driver in PDAC. A small subset of PDACs harbor KRAS-wild-type (WT). We aim to characterize the molecular profiles of KRAS-WT PDAC to uncover new pathogenic drivers and offer targeted treatments.EXPERIMENTAL DESIGN: Tumor tissue obtained from surgical or biopsy material was subjected to next-generation DNA/RNA sequencing, microsatellite-instability (MSI) and mismatch-repair (MMR) status determination.
    RESULTS: Of the 2,483 patients (male 53.7%, median-age 66 years) studied, 266 tumors (10.7%) were KRAS-WT. The most frequently mutated gene in KRAS-WT-PDAC was TP53 (44.5%), followed by BRAF (13.0%) . Multiple mutations within the DNA-damage-repair (BRCA2, ATM, BAP1, RAD50, FANCE, PALB2), chromatin-remodeling (ARID1A, PBRM1, ARID2, KMT2D, KMT2C, SMARCA4, SETD2), and cell-cycle-control pathways (CDKN2A, CCND1, CCNE1) were detected frequently. There was no statistically-significant difference in PDL1-expression between KRAS-WT (15.8%) and MT (17%) tumors. However, KRAS-WT-PDAC were more likely to be MSI-high (4.7% vs 0.7%; p&lt;0.05), TMB-high (4.5% vs 1%; p&lt;0.05), and exhibit increased infiltration of CD8+ T-cells, NK-cells and myeloid dendritic cells. KRAS-WT-PDACs exhibited gene fusions of BRAF (6.6%), FGFR2 (5.2%), ALK (2.6%), RET (1.3%) and NRG1 (1.3%), as well as amplification of FGF3 (3%), ERBB2 (2.2%), FGFR3 (1.8%), NTRK (1.8%) and MET (1.3%). Real-world evidence reveals a survival advantage of KRAS-WT patients in overall cohorts as well as in patients treated with gemcitabine/nab-paclitaxel or 5FU/oxaliplatin.
    CONCLUSIONS: KRAS-WT PDAC represents 10.7% of PDAC and is enriched with targetable alterations, including immuno-oncologic markers. Identification of KRAS-WT patients in clinical practice may expand therapeutic options in a clinically meaningful manner.
    DOI:  https://doi.org/10.1158/1078-0432.CCR-21-3581
  21. Biochim Biophys Acta Rev Cancer. 2022 Mar 15. pii: S0304-419X(22)00043-9. [Epub ahead of print] 188718
      Growing evidence exposes translation and its translational machinery as key players in establishing and maintaining physiological and pathological biological processes. Examining translation may not only provide new biological insight but also identify novel innovative therapeutic targets in several fields of biology, including that of epithelial-to-mesenchymal transition (EMT). EMT is currently considered as a dynamic and reversible transdifferentiation process sustaining the transition from an epithelial to mesenchymal phenotype, known to be mainly driven by transcriptional reprogramming. However, it seems that the characterization of EMT plasticity is challenging, relying exclusively on transcriptomic and epigenetic approaches. Indeed, heterogeneity in EMT programs was reported to depend on the biological context. Here, by reviewing the involvement of translational control, translational machinery and ribosome biogenesis characterizing the different types of EMT, from embryonic and adult physiological to pathological contexts, we discuss the added value of integrating translational control and its machinery to depict the heterogeneity and dynamics of EMT programs.
    Keywords:  Cancer; Components of translational machinery; Development; Epithelial to mesenchymal transition (EMT); Fibrosis; Ribosome; Translation
    DOI:  https://doi.org/10.1016/j.bbcan.2022.188718