bims-instec 2023-03-12 papers

bims-instec

Biomed News

on Intestinal stem cells and chemoresistance in colon cancer and intestinal regeneration

Issue of 2023–03–12
eleven papers selected by
Maria-Virginia Giolito, Free University of Brussels

Ablation of p57+ Quiescent Cancer Stem Cells Suppresses Recurrence After Chemotherapy of Intestinal Tumors.
Stiffness Restricts the Stemness of the Intestinal Stem Cells and Skews Their Differentiation Towards Goblet Cells.
TIMP-2 as a predictive biomarker in 5-Fu-resistant colorectal cancer.
The intestine: A highly dynamic microenvironment for IgA plasma cells.
Patient-Derived Tumor Organoids Can Predict the Progression-Free Survival of Stage IV Colorectal Cancer Patients After Surgery.
5-Fluorouracil Suppresses Colon Tumor through Activating the p53-Fas Pathway to Sensitize Myeloid-Derived Suppressor Cells to FasL+ Cytotoxic T Lymphocyte Cytotoxicity.
Hedgehog-GLI and Notch Pathways Sustain Chemoresistance and Invasiveness in Colorectal Cancer and Their Inhibition Restores Chemotherapy Efficacy.
Efficacy of third-line anti-EGFR-based treatment versus regorafenib or trifluridine/tipiracil according to primary tumor site in RAS/BRAF wild-type metastatic colorectal cancer patients.
MUC1-C is necessary for SHP2 activation and BRAF inhibitor resistance in BRAF(V600E) mutant colorectal cancer.
Cetuximab as third-line rechallenge plus either irinotecan or avelumab is an effective treatment in metastatic colorectal cancer patients with baseline plasma RAS/BRAF wild-type circulating tumor DNA: Individual patient data pooled analysis of CRICKET and CAVE trials.
PARP-1 Expression Influences Cancer Stem Cell Phenotype in Colorectal Cancer Depending on p53.

Cancer Res. 2023 Mar 07. pii: CAN-22-2578. [Epub ahead of print]

Ablation of p57+ Quiescent Cancer Stem Cells Suppresses Recurrence After Chemotherapy of Intestinal Tumors.

Takeru Oka, Tsunaki Higa, Osamu Sugahara, Daisuke Koga, Shogo Nakayama, Keiichi I Nakayama.

Quiescent cancer stem cells (CSCs) are resistant to conventional anti-cancer treatments and have been shown to contribute to disease relapse after therapy in some cancer types. The identification and characterization of quiescent CSCs could facilitate the development of strategies to target this cell population and block recurrence. Here, we established a syngeneic orthotopic transplantation model in mice based on intestinal cancer organoids to profile quiescent CSCs. Single-cell transcriptomic analysis of the primary tumors formed in vivo revealed that conventional Lgr5high intestinal CSCs comprise both actively and slowly cycling subpopulations, the latter of which specifically expresses the cyclin-dependent kinase inhibitor p57. Tumorigenicity assays and lineage tracing experiments showed that the quiescent p57+ CSCs contribute in only a limited manner to steady-state tumor growth but they are chemotherapy resistant and drive post-therapeutic cancer recurrence. Ablation of p57+ CSCs suppressed intestinal tumor regrowth after chemotherapy. Together, these results shed light on the heterogeneity of intestinal CSCs and reveal p57+ CSCs as a promising therapeutic target for malignant intestinal cancer.

DOI: https://doi.org/10.1158/0008-5472.CAN-22-2578
Gastroenterology. 2023 Mar 03. pii: S0016-5085(23)00215-9. [Epub ahead of print]

Stiffness Restricts the Stemness of the Intestinal Stem Cells and Skews Their Differentiation Towards Goblet Cells.

Shijie He, Peng Lei, Wenying Kang, Priscilla Cheung, Tao Xu, Miyeko Mana, Chan Young Park, Hongyan Wang, Shinya Imada, Jacquelyn O Russell, Jianxun Wang, Ruizhi Wang, Ziheng Zhou, Kashish Chetal, Eric Stas, Vidisha Mohad, Peter Bruun-Rasmussen, Ruslan I Sadreyev, Richard A Hodin, Yanhang Zhang, David T Breault, Fernando D Camargo, Ömer H Yilmaz, Jeffrey J Fredberg, Nima Saeidi.

   BACKGROUND & AIMS: Fibrosis and tissue stiffening are hallmarks of the inflammatory bowel disease (IBD). We have hypothesized that the increased stiffness directly contributes to the dysregulation of the epithelial cell homeostasis in IBD. Here, we aim to determine the impact of tissue stiffening on the fate and function of the intestinal stem cells (ISCs).
METHODS: We developed a long-term culture system consisting of 2.5-dimensional intestinal organoids grown on a hydrogel matrix with tunable stiffness. Single-cell RNA sequencing provided stiffness-regulated transcriptional signatures of the ISCs and their differentiated progeny. YAP-knockout and YAP-overexpression mice were used to manipulate YAP expression. In addition, we analyzed colon samples from murine colitis models and human IBD samples to assess the impact of stiffness on ISCs in vivo.
RESULTS: We demonstrated that increasing the stiffness potently reduced the population of LGR5+ ISCs and KI-67+ proliferating cells. Conversely, cells expressing the stem cell marker, OLFM4, became dominant in the crypt-like compartments and pervaded the villus-like regions. Concomitantly, stiffening prompted the ISCs to preferentially differentiate toward goblet cells. Mechanistically, stiffening increased the expression of cytosolic YAP, driving the extension of OLFM4+ cells into the villus-like regions, while it induced the nuclear translocation of YAP, leading to preferential differentiation of ISCs towards goblet cells. Furthermore, analysis of colon samples from murine colitis models and IBD patients demonstrated cellular and molecular remodeling reminiscent of those observed in vitro.
CONCLUSIONS: Collectively, our findings highlight that matrix stiffness potently regulates the stemness of ISCs and their differentiation trajectory, supporting the hypothesis that fibrosis-induced gut stiffening plays a direct role in epithelial remodeling in IBD.

Keywords:  IBD; and intestinal stem cells; fibrosis; intestinal organoids; stiffening

DOI:  https://doi.org/10.1053/j.gastro.2023.02.030
J Cancer Res Clin Oncol. 2023 Mar 11.

TIMP-2 as a predictive biomarker in 5-Fu-resistant colorectal cancer.

Yaoqing Li, Chuchu Xu, Renjun Zhu, Liyijing Shen, Gengyuan Hu, Kelong Tao, Feng Tao, Zengxin Lu, Guolin Zhang.

   PURPOSE: This study aims to evaluate the value of tissue inhibitors of MMPs-2 (TIMP-2) to indicate 5-Fluorouracil (5-Fu) resistance status in colorectal cancer.
METHODS: The 5-Fu resistance of colorectal cancer cell lines was detected using Cell-Counting Kit-8 (CCK-8) and calculated using IC50. Enzyme-linked immunosorbent assay (ELISA) and real time-quantitative polymerase chain reaction (RT-qPCR) were used to detect TIMP-2 expression level in the culture supernatant and serum. Twenty-two colorectal cancer patients' TIMP-2 levels and clinical characteristics were analyzed before and after chemotherapy. Additionally, the patient-derived xenograft (PDX) model of 5-Fu resistance was used to evaluate the feasibility of TIMP-2 as a predictive biomarker of 5-Fu resistance.
RESULTS: Our experimental results display that TIMP-2 expression is elevated in colorectal cancer drug-resistant cell lines, and its expression level is closely related to 5-Fu resistance. Moreover, TIMP-2 in colorectal cancer patient serum undergoing 5-Fu-based chemotherapy could indicate their drug resistance status, and its efficacy is higher than CEA and CA19-9. Finally, PDX model animal experiments reveal that TIMP-2 can detect 5-Fu resistance in colorectal cancer earlier than tumor volume.
CONCLUSION: TIMP-2 is a good indicator of 5-Fu resistance in colorectal cancer. Monitoring the serum TIMP-2 level can help the clinician identify 5-Fu resistance in colorectal cancer patients earlier during chemotherapy.

Keywords:  5-Fu; Biomarker; Colorectal cancer; Drug resistance; TIMP-2

DOI:  https://doi.org/10.1007/s00432-023-04670-w
Front Immunol. 2023 ;14 1114348

The intestine: A highly dynamic microenvironment for IgA plasma cells.

Katharina Pracht, Jens Wittner, Fritz Kagerer, Hans-Martin Jäck, Wolfgang Schuh.

  To achieve longevity, IgA plasma cells require a sophisticated anatomical microenvironment that provides cytokines, cell-cell contacts, and nutrients as well as metabolites. The intestinal epithelium harbors cells with distinct functions and represents an important defense line. Anti-microbial peptide-producing paneth cells, mucus-secreting goblet cells and antigen-transporting microfold (M) cells cooperate to build a protective barrier against pathogens. In addition, intestinal epithelial cells are instrumental in the transcytosis of IgA to the gut lumen, and support plasma cell survival by producing the cytokines APRIL and BAFF. Moreover, nutrients are sensed through specialized receptors such as the aryl hydrocarbon receptor (AhR) by both, intestinal epithelial cells and immune cells. However, the intestinal epithelium is highly dynamic with a high cellular turn-over rate and exposure to changing microbiota and nutritional factors. In this review, we discuss the spatial interplay of the intestinal epithelium with plasma cells and its potential contribution to IgA plasma cell generation, homing, and longevity. Moreover, we describe the impact of nutritional AhR ligands on intestinal epithelial cell-IgA plasma cell interaction. Finally, we introduce spatial transcriptomics as a new technology to address open questions in intestinal IgA plasma cell biology.

Keywords:  Aryl hydrocarbon (Ah) receptor; IgA; IgA plasma cells; intestinal epithelial barrier; intestinal epithelial cell; plasma cell; survival niche

DOI:  https://doi.org/10.3389/fimmu.2023.1114348
Dis Colon Rectum. 2023 Mar 09.

Patient-Derived Tumor Organoids Can Predict the Progression-Free Survival of Stage IV Colorectal Cancer Patients After Surgery.

Ting Wang, Yuting Tang, Wenjun Pan, Botao Yan, Yifan Hao, Yunli Zeng, Zexin Chen, Jianqiang Lan, Shuhan Zhao, Chuxia Deng, Hang Zheng, Jun Yan.

BACKGROUND: Recent studies have shown patient-derived tumor organoid can predict the drug response of cancer patients. However, the prognostic value of patient-derived tumor organoid-based drug tests in predicting the progression-free survival of stage IV colorectal cancer patients after surgery remains unknown.
OBJECTIVE: To explore the prognostic value of patient-derived tumor organoid-based drug tests in stage IV colorectal cancer patients after surgery.
DESIGN: Retrospective cohort study.
SETTINGS: Surgical samples were obtained from stage IV colorectal cancer patients at Nanfang Hospital.
PATIENTS: A total of 108 patients who underwent surgery with successful patient-derived tumor organoid culture and drug testing were recruited between June 2018 and June 2019.
INTERVENTIONS: Patient-derived tumor organoid culture and chemotherapeutic drug testing.
MAIN OUTCOMES MEASURES: Progression-free survival.
RESULTS: According to the patient-derived tumor organoid-based drug test, 38 patients were drug-sensitive, and 76 patients were drug-resistant. The median progression-free survival was 16.0 months in the drug-sensitive group and 9.0 months in the drug-resistant group (p < 0.001). Multivariate analyses showed that drug resistance (HR, 3.38; 95% CI, 1.84-6.21; p < 0.001), right-sided colon (HR, 3.50; 95% CI, 1.71-7.15; p < 0.001), mucinous adenocarcinoma (HR, 2.47; 95% CI, 1.34-4.55; p = 0.004), and non-R0 resection (HR, 2.70; 95% CI, 1.61-4.54; p < 0.001) were independent predictors of progression-free survival. The new patient-derived tumor organoid-based drug test model, which includes the patient-derived tumor organoid-based drug test, primary tumor location, histological type, and R0 resection, was more accurate than the traditional clinicopathological model in predicting progression-free survival (p = 0.001).
LIMITATIONS: A single-center cohort study.
CONCLUSIONS: Patient-derived tumor organoid can predict progression-free survival in stage IV colorectal cancer patients after surgery. Patient-derived tumor organoid drug resistance is associated with shorter progression-free survival, and the addition of patient-derived tumor organoid drug tests to existing clinicopathological models improves the ability to predict progression-free survival.

DOI: https://doi.org/10.1097/DCR.0000000000002511
Cancers (Basel). 2023 Mar 02. pii: 1563. [Epub ahead of print]15(5):

5-Fluorouracil Suppresses Colon Tumor through Activating the p53-Fas Pathway to Sensitize Myeloid-Derived Suppressor Cells to FasL+ Cytotoxic T Lymphocyte Cytotoxicity.

Yingcui Yang, Mingqing Zhang, Yongdan Zhang, Kebin Liu, Chunwan Lu.

  Myelosuppression is a major adverse effect of 5-fluorouracil (5-FU) chemotherapy. However, recent findings indicate that 5-FU selectively suppresses myeloid-derived suppressor cells (MDSCs), to enhance antitumor immunity in tumor-bearing mice. 5-FU-mediated myelosuppression may thus have a beneficial effect for cancer patients. The molecular mechanism underlying 5-FU's suppression of MDSCs is currently unknown. We aimed at testing the hypothesis that 5-FU suppresses MDSCs through enhancing MDSC sensitivity to Fas-mediated apoptosis. We observed that, although FasL is highly expressed in T cells, Fas is weakly expressed in myeloid cells in human colon carcinoma, indicating that downregulation of Fas is a mechanism underlying myeloid cell survival and accumulation in human colon cancer. 5-FU treatment upregulated expression of both p53 and Fas, and knocking down p53 diminished 5-FU-induced Fas expression in MDSC-like cells, in vitro. 5-FU treatment also increased MDSC-like cell sensitivity to FasL-induced apoptosis in vitro. Furthermore, we determined that 5-FU therapy increased expression of Fas on MDSCs, suppressed MDSC accumulation, and increased CTL tumor infiltration in colon tumor-bearing mice. In human colorectal cancer patients, 5-FU chemotherapy decreased MDSC accumulation and increased CTL level. Our findings determine that 5-FU chemotherapy activates the p53-Fas pathway, to suppress MDSC accumulation, to increase CTL tumor infiltration.

Keywords:  5-FU; Fas; MDSCs; colorectal cancer; cytotoxic T lymphocytes; p53

DOI:  https://doi.org/10.3390/cancers15051563
Cancers (Basel). 2023 Feb 25. pii: 1471. [Epub ahead of print]15(5):

Hedgehog-GLI and Notch Pathways Sustain Chemoresistance and Invasiveness in Colorectal Cancer and Their Inhibition Restores Chemotherapy Efficacy.

Anna Citarella, Giuseppina Catanzaro, Zein Mersini Besharat, Sofia Trocchianesi, Federica Barbagallo, Giorgio Gosti, Marco Leonetti, Annamaria Di Fiore, Lucia Coppola, Tanja Milena Autilio, Zaira Spinello, Alessandra Vacca, Enrico De Smaele, Mary Anna Venneri, Elisabetta Ferretti, Laura Masuelli, Agnese Po.

  Colorectal cancer (CRC) is a leading cause of cancer-related mortality and chemoresistance is a major medical issue. The epithelial-to-mesenchymal transition (EMT) is the primary step in the emergence of the invasive phenotype and the Hedgehog-GLI (HH-GLI) and NOTCH signaling pathways are associated with poor prognosis and EMT in CRC. CRC cell lines harboring KRAS or BRAF mutations, grown as monolayers and organoids, were treated with the chemotherapeutic agent 5-Fluorouracil (5-FU) alone or combined with HH-GLI and NOTCH pathway inhibitors GANT61 and DAPT, or arsenic trioxide (ATO) to inhibit both pathways. Treatment with 5-FU led to the activation of HH-GLI and NOTCH pathways in both models. In KRAS mutant CRC, HH-GLI and NOTCH signaling activation co-operate to enhance chemoresistance and cell motility, while in BRAF mutant CRC, the HH-GLI pathway drives the chemoresistant and motile phenotype. We then showed that 5-FU promotes the mesenchymal and thus invasive phenotype in KRAS and BRAF mutant organoids and that chemosensitivity could be restored by targeting the HH-GLI pathway in BRAF mutant CRC or both HH-GLI and NOTCH pathways in KRAS mutant CRC. We suggest that in KRAS-driven CRC, the FDA-approved ATO acts as a chemotherapeutic sensitizer, whereas GANT61 is a promising chemotherapeutic sensitizer in BRAF-driven CRC.

Keywords:  chemoresistance; colorectal cancer; epithelial-to-mesenchymal transition; organoids; signaling pathways

DOI:  https://doi.org/10.3390/cancers15051471
Front Oncol. 2023 ;13 1125013

Efficacy of third-line anti-EGFR-based treatment versus regorafenib or trifluridine/tipiracil according to primary tumor site in RAS/BRAF wild-type metastatic colorectal cancer patients.

Lisa Salvatore, Maria Bensi, Raffaella Vivolo, Ina Valeria Zurlo, Emanuela Dell'Aquila, Roberta Grande, Annunziato Anghelone, Alessandra Emiliani, Fabrizio Citarella, Maria Alessandra Calegari, Marta Ribelli, Michele Basso, Carmelo Pozzo, Giampaolo Tortora.

   Background: Right- (R) and left-sided (L) metastatic colorectal cancer (mCRC) exhibit different clinical and molecular features. Several retrospective analyses showed that survival benefit of anti-EGFR-based therapy is limited to RAS/BRAF wt L-sided mCRC patients. Few data are available about third-line anti-EGFR efficacy according to primary tumor site.
Methods: RAS/BRAF wt patients mCRC treated with third-line anti-EGFR-based therapy versus regorafenib or trifluridine/tipiracil (R/T) were retrospectively collected. The objective of the analysis was to compare treatment efficacy according to tumor site. The primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS), response rate (RR) and toxicity.
Results: A total of 76 RAS/BRAF wt mCRC patients, treated with third-line anti-EGFR-based therapy or R/T, were enrolled. Of those, 19 (25%) patients had a R-sided tumor (9 patients received anti-EGFR treatment and 10 patients R/T) and 57 (75%) patients had a L-sided tumor (30 patients received anti-EGFR treatment and 27 patients R/T). A significant PFS [7.2 vs 3.6 months, HR 0.43 (95% CI 0.2-0.76), p= 0.004] and OS benefit [14.9 vs 10.9 months, HR 0.52 (95% CI 0.28-0.98), p= 0.045] in favor of anti-EGFR therapy vs R/T was observed in the L-sided tumor group. No difference in PFS and OS was observed in the R-sided tumor group. A significant interaction according to primary tumor site and third-line regimen was observed for PFS (p= 0.05). RR was significantly higher in L-sided patients treated with anti-EGFR vs R/T (43% vs. 0%; p <0.0001), no difference was observed in R-sided patients. At the multivariate analysis, third-line regimen was independently associated with PFS in L-sided patients.
Conclusions: Our results demonstrated a different benefit from third-line anti-EGFR-based therapy according to primary tumor site, confirming the role of L-sided tumor in predicting benefit from third-line anti-EGFR vs R/T. At the same time, no difference was observed in R-sided tumor.

Keywords:  RAS/BRAF wild-type; Regorafenib; anti-egfr ab; colorectal cancer; primary tumor site; third-line therapy; trifluridine/tipiracil

DOI:  https://doi.org/10.3389/fonc.2023.1125013
Cancer Lett. 2023 Mar 05. pii: S0304-3835(23)00067-8. [Epub ahead of print]559 216116

MUC1-C is necessary for SHP2 activation and BRAF inhibitor resistance in BRAF(V600E) mutant colorectal cancer.

Yoshihiro Morimoto, Nami Yamashita, Haruka Hirose, Atsushi Fushimi, Naoki Haratake, Tatsuaki Daimon, Atrayee Bhattacharya, Rehan Ahmad, Yozo Suzuki, Hidekazu Takahashi, Donald W Kufe.

  Colorectal cancers (CRCs) harboring the BRAF(V600E) mutation are associated with aggressive disease and resistance to BRAF inhibitors by feedback activation of the receptor tyrosine kinase (RTK)→RAS→MAPK pathway. The oncogenic MUC1-C protein promotes progression of colitis to CRC; whereas there is no known involvement of MUC1-C in BRAF(V600E) CRCs. The present work demonstrates that MUC1 expression is significantly upregulated in BRAF(V600E) vs wild-type CRCs. We show that BRAF(V600E) CRC cells are dependent on MUC1-C for proliferation and BRAF inhibitor (BRAFi) resistance. Mechanistically, MUC1-C integrates induction of MYC in driving cell cycle progression with activation of the SHP2 phosphotyrosine phosphatase, which enhances RTK-mediated RAS→ERK signaling. We demonstrate that targeting MUC1-C genetically and pharmacologically suppresses (i) activation of MYC, (ii) induction of the NOTCH1 stemness factor, and (iii) the capacity for self-renewal. We also show that MUC1-C associates with SHP2 and is required for SHP2 activation in driving BRAFi-induced feedback of ERK signaling. In this way, targeting MUC1-C in BRAFi-resistant BRAF(V600E) CRC tumors inhibits growth and sensitizes to BRAF inhibition. These findings demonstrate that MUC1-C is a target for the treatment of BRAF(V600E) CRCs and for reversing their resistance to BRAF inhibitors by suppressing the feedback MAPK pathway.

Keywords:  BRAF inhibitor Resistance; BRAF(V600E); CRC; MUC1-C; SHP2

DOI:  https://doi.org/10.1016/j.canlet.2023.216116
Cancer Med. 2023 Mar 07.

Cetuximab as third-line rechallenge plus either irinotecan or avelumab is an effective treatment in metastatic colorectal cancer patients with baseline plasma RAS/BRAF wild-type circulating tumor DNA: Individual patient data pooled analysis of CRICKET and CAVE trials.

G Martini, D Ciardiello, V Famiglietti, D Rossini, C Antoniotti, T Troiani, S Napolitano, L Esposito, T P Latiano, E Maiello, M Del Re, S Lonardi, G Aprile, D Santini, G Masi, A Avallone, N Normanno, F Pietrantonio, C Pinto, F Ciardiello, C Cremolini, E Martinelli.

  The rechallenge strategy is based on the concept that a subset of patients with RAS wild-type (WT) metastatic colorectal cancer (mCRC) could still benefit of epidermal growth factor receptor (EGFR) inhibition, after progression to an anti-EGFR based-therapy. We performed a pooled analysis of two-phase II prospective trials to determine the role of rechallenge in third-line mCRC patients with RAS/BRAF WT baseline circulating tumor DNA (ctDNA). Individual data of 33 and 13 patients from CAVE and CRICKET trials that received as third-line therapy cetuximab rechallenge were collected. Overall survival (OS), Progression-free survival (PFS), Overall response rate (ORR), Stable disease (SD) >6 months were calculated. Adverse events were reported. For the whole 46 patient population, median PFS (mPFS) was 3.9 months (95% Confidence Interval, CI 3.0-4.9) with median OS (mOS) of 16.9 months (95% CI 11.7-22.1). For CRICKET patients, mPFS was 3.9 months (95% CI 1.7-6.2); mOS was 13.1 months (95% CI 7.3-18.9) with OS rates at 12, 18, and 24 months of 62%, 23%, and 0%, respectively. For CAVE patients, mPFS was 4.1 months (95% CI 3.0-5.2); mOS was 18.6 months (95% CI 11.7-25.4) with OS rates at 12, 18, 24 months of 61%, 52%, 21%, respectively. Skin rash was more frequently reported in CAVE trial (87.9% vs. 30.8%; p = 0.001), whereas a increased incidence of hematological toxicities was observed in CRICKET trial (53.8%% vs. 12.1%; p = 0.003). Third-line cetuximab rechallenge in combination with either irinotecan or avelumab in RAS/BRAF WT ctDNA mCRC patients represents a promising therapy.

Keywords:  cetuximab; immunotherapy; metastatic colorectal cancer; rechallenge

DOI:  https://doi.org/10.1002/cam4.5699
Int J Mol Sci. 2023 Mar 01. pii: 4787. [Epub ahead of print]24(5):

PARP-1 Expression Influences Cancer Stem Cell Phenotype in Colorectal Cancer Depending on p53.

Jose D Puentes-Pardo, Sara Moreno-SanJuan, Jorge Casado, Julia Escudero-Feliu, David López-Pérez, Paula Sánchez-Uceta, Paula González-Novoa, Julio Gálvez, Ángel Carazo, Josefa León.

  Poly(ADP-ribose) polymerase-1 (PARP-1) is a protein involved in multiple physiological processes. Elevated PARP-1 expression has been found in several tumours, being associated with stemness and tumorigenesis. In colorectal cancer (CRC), some controversy among studies has been described. In this study, we analysed the expression of PARP-1 and cancer stem cell (CSC) markers in CRC patients with different p53 status. In addition, we used an in vitro model to evaluate the influence of PARP-1 in CSC phenotype regarding p53. In CRC patients, PARP-1 expression correlated with the differentiation grade, but this association was only maintained for tumours harbouring wild-type p53. Additionally, in those tumours, PARP-1 and CSC markers were positively correlated. In mutated p53 tumours, no associations were found, but PARP-1 was an independent factor for survival. According to our in vitro model, PARP-1 regulates CSC phenotype depending on p53 status. PARP-1 overexpression in a wild type p53 context increases CSC markers and sphere forming ability. By contrast, those features were reduced in mutated p53 cells. These results could implicate that patients with elevated PARP-1 expression and wild type p53 could benefit from PARP-1 inhibition therapies, meanwhile it could have adverse effects for those carrying mutated p53 tumours.

Keywords:  PARP-1; cancer stem cells; colorectal cancer; p53

DOI:  https://doi.org/10.3390/ijms24054787