Papers by Justine Bellier
Cell Reports, Feb 1, 2020
Highlights d Glycolytic mutant KRAS display higher MGO stress than wildtype CRC cells d MGO stres... more Highlights d Glycolytic mutant KRAS display higher MGO stress than wildtype CRC cells d MGO stress is a potent inducer of AKT signaling in CRC cells d MGO stress induces resistance to anti-EGFR therapy in a wild-type KRAS setting d Carnosine, an MGO scavenger, sensitizes mutant KRAS CRC tumors to anti-EGFR therapy
ESMO open, Jun 1, 2018
and 94% N 2) conditions. Cells were washed and snap frozen within 5 min after incubation. Hypoxic... more and 94% N 2) conditions. Cells were washed and snap frozen within 5 min after incubation. Hypoxic response in cells was verified by HIF1a expression in Western blot analysis. FTIR spectra of cancer cells were registered using HTS-XT microplate reader coupled with Vertex 70 (Bruker), and recorded in the frequency range of 4000-600 cm À1 , with the spectral resolution of 4 cm À1 and 64 scans. Quantitative analysis of cell macromolecular composition was done as in (Grube et al. 2002). As characteristic absorption bands were used 1080 cm À1 for carbohydrates, 1250 cm À1 for nucleic acids, 1550 cm À1 for proteins and 2930 cm À1 for lipids. Results and discussions Results showed differences in biochemical composition of prostate and lung cancer cells even under normoxic growth conditions. The carbohydrate content in NCI-H69 cells was 8.16% of dry weight (dw), in PC3 cells-11.60% dw. The lipid content in NCI-H69 cells was 10.91% dw, but in PC3%-13.58% dw. The hypoxia induced metabolic response of prostate and lung cancer cells was more pronounced as an increase of lipid contente.g., the lipid content in hypoxic cells of NCI-H69 was 13.29% dw, but in PC3%-15.91% dw. Thus, hypoxia induced lipid increase in lung cancer cells was for 22% but in prostate cancer cells for 17% compared to that in normoxic cells. These results are in line with our previous results and thus might represent universal mechanism and the observed total lipid content increase due to hypoxia could have a potential value for further studies of cancer cell lipid metabolism. Conclusion The results of this study showed that under oxygen stressstarvation (hypoxia) the metabolism of lipids was much more affected than that of proteins, nucleic acids or carbohydrates suggesting that regulation of lipid synthesis can possibly provide advantages for cancer cell survival in extreme growth conditions.
ESMO open, Jun 1, 2018
and 94% N 2) conditions. Cells were washed and snap frozen within 5 min after incubation. Hypoxic... more and 94% N 2) conditions. Cells were washed and snap frozen within 5 min after incubation. Hypoxic response in cells was verified by HIF1a expression in Western blot analysis. FTIR spectra of cancer cells were registered using HTS-XT microplate reader coupled with Vertex 70 (Bruker), and recorded in the frequency range of 4000-600 cm À1 , with the spectral resolution of 4 cm À1 and 64 scans. Quantitative analysis of cell macromolecular composition was done as in (Grube et al. 2002). As characteristic absorption bands were used 1080 cm À1 for carbohydrates, 1250 cm À1 for nucleic acids, 1550 cm À1 for proteins and 2930 cm À1 for lipids. Results and discussions Results showed differences in biochemical composition of prostate and lung cancer cells even under normoxic growth conditions. The carbohydrate content in NCI-H69 cells was 8.16% of dry weight (dw), in PC3 cells-11.60% dw. The lipid content in NCI-H69 cells was 10.91% dw, but in PC3%-13.58% dw. The hypoxia induced metabolic response of prostate and lung cancer cells was more pronounced as an increase of lipid contente.g., the lipid content in hypoxic cells of NCI-H69 was 13.29% dw, but in PC3%-15.91% dw. Thus, hypoxia induced lipid increase in lung cancer cells was for 22% but in prostate cancer cells for 17% compared to that in normoxic cells. These results are in line with our previous results and thus might represent universal mechanism and the observed total lipid content increase due to hypoxia could have a potential value for further studies of cancer cell lipid metabolism. Conclusion The results of this study showed that under oxygen stressstarvation (hypoxia) the metabolism of lipids was much more affected than that of proteins, nucleic acids or carbohydrates suggesting that regulation of lipid synthesis can possibly provide advantages for cancer cell survival in extreme growth conditions.
Our results indicate that myoferlin expression is higher in colon cancer than in normal adjacent ... more Our results indicate that myoferlin expression is higher in colon cancer than in normal adjacent tissue and that is associated to poor survival. Myoferlin depletion leads to a mitochondrial respiration decrease and a mitochondrial fission inducing probably ROS production and subsequent DNA damages. Moreover, myoferlin silencing in p53 wild-type HCT116 cell line is leading to cell cycle arrest, apoptosis and important decrease in cell growth. In conclusion, as apoptosis resistance is one of the most important resistance mechanism in COAD, myoferlin targetting could open up a new perspective in the development of new treatment for p53 WT patients.
Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related death. Thera... more Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related death. Therapeutic options remain very limited and are based on classical chemotherapies. Energy metabolism reprogramming appears as an emerging hallmark of cancer and is considered a therapeutic target with considerable potential. Myoferlin, a ferlin family member protein overexpressed in PDAC, is involved in plasma membrane biology and has a tumor-promoting function. In the continuity of our previous studies, we investigated the role of myoferlin in the context of energy metabolism in PDAC. We used selected PDAC tumor samples and PDAC cell lines together with small interfering RNA technology to study the role of myoferlin in energetic metabolism. In PDAC patients, we showed that myoferlin expression is negatively correlated with overall survival and with glycolytic activity evaluated by 18 F-deoxyglucose positron emission tomography. We found out that myoferlin is more abundant in lipogenic pancreatic cancer cell lines and is required to maintain a branched mitochondrial structure and a high oxidative phosphorylation activity. The observed mitochondrial fission induced by myoferlin depletion led to a decrease of cell proliferation, ATP production, and autophagy induction, thus indicating an essential role of myoferlin for PDAC cell fitness. The metabolic phenotype switch generated by myoferlin silencing could open up a new perspective in the development of therapeutic strategies, especially in the context of energy metabolism.
Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer, and the thi... more Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer, and the third leading cause of cancer related death. Therapeutic options remain very limited and are still based on classical chemotherapies. Cell fraction can survive to the chemotherapy and is responsible for tumor relapse. It appears that these cells rely on OXPHOS for survival. Myoferlin, a membrane protein involved in cell fusion was recently shown by our laboratory to be overexpressed in pancreatic cancer. In the present study, we discovered that myoferlin was more expressed in cell lines undergoing oxidative phosphorylation (OXPHOS) than in glycolytic cell lines. In the former cell lines, we showed that myoferlin silencing reduced OXPHOS activity and forced cells to switch to glycolysis. The decrease in OXPHOS activity is associated with mitochondrial network disorganization. Dynamin-related protein (DRP)-1 phosphorylation led us to suggest mitochondrial fission, reducing cell proliferation, ATP production and inducing autophagy and ROS accumulation. To confirm the clinical importance of myoferlin in PDAC, we showed that low myoferlin expression was significantly correlated to high overall survival. Myoferlin staining of PDAC sections was negatively correlated with several 18FDG PET indices indicating that glycolytic lesions had less myoferlin. As the mitochondrial function is demonstrated to enhance the cell resistance to the treatment, the metabolic switch forced by myoferlin silencing could open up a new perspective in the development of therapeutic strategies
Oncogenesis, Mar 2, 2023
During figure preparation, the same protein samples were used in the western blots depicted in fi... more During figure preparation, the same protein samples were used in the western blots depicted in figures 4 and 5. For the sake of completeness, the same myoferlin western blots were included in figures 4 and 5. It has been noted that the western blot duplication can be misleading. Consequently, the duplicated myoferlin western blots have been removed from figures 4 and 5. The corrected figures are presented below.
Journal of Experimental & Clinical Cancer Research, Mar 31, 2023
Background Aerobic glycolysis, also known as the Warburg effect, is predominantly upregulated in ... more Background Aerobic glycolysis, also known as the Warburg effect, is predominantly upregulated in a variety of solid tumors, including breast cancer. We have previously reported that methylglyoxal (MG), a very reactive by-product of glycolysis, unexpectedly enhanced the metastatic potential in triple negative breast cancer (TNBC) cells. MG and MGderived glycation products have been associated with various diseases, such as diabetes, neurodegenerative disorders, and cancer. Glyoxalase 1 (GLO1) exerts an anti-glycation defense by detoxifying MG to D-lactate. Methods Here, we used our validated model consisting of stable GLO1 depletion to induce MG stress in TNBC cells. Using genome-scale DNA methylation analysis, we report that this condition resulted in DNA hypermethylation in TNBC cells and xenografts. Results GLO1-depleted breast cancer cells showed elevated expression of DNMT3B methyltransferase and significant loss of metastasis-related tumor suppressor genes, as assessed using integrated analysis of methylome and transcriptome data. Interestingly, MG scavengers revealed to be as potent as typical DNA demethylating agents at triggering the re-expression of representative silenced genes. Importantly, we delineated an epigenomic MG signature that effectively stratified TNBC patients based on survival. Conclusion This study emphasizes the importance of MG oncometabolite, occurring downstream of the Warburg effect, as a novel epigenetic regulator and proposes MG scavengers to reverse altered patterns of gene expression in TNBC.
Oral Oncology, Apr 1, 2017
Objectives: Head and neck squamous cell carcinomas (HNSCC), one of the most frequent cancers in t... more Objectives: Head and neck squamous cell carcinomas (HNSCC), one of the most frequent cancers in the world, are largely infiltrated by inflammatory immune cells. Our aim was to evaluate the number of Foxp3+ T cells in HNSCC, reporting its prognostic power in comparison to other risk factors. Material and methods: Our clinical series was composed of 21 tumor-free peri-tumoral epithelia, 49 low grade dysplasia, 43 high grade dysplasia and 110 carcinoma samples including some cases with HPV infection. In vivo experiments were conducted on 80 C3 H/HeN mice which were orthotopically injected with SCCVII CT, E7, E6 and E6/E7 cell lines. Results: Foxp3+ T cell infiltration increased with tumor progression from normal epithelia, dysplasia to carcinoma and the increase is more important in HPV+ patients than in negative ones. Animal experiments revealed that E7 oncoprotein expression was significantly associated with an increase in Foxp3+ T cell recruitment in tumor, a delay in tumor onset and improved animal survival. Univariate Cox regression analyses demonstrated that high Foxp3+ T cell number in stromal compartment is associated with longer patient recurrence-free and overall survivals. Foxp3+ T cell number improved the prognostic value of tumor stage. Multivariate analyses reported that stromal Foxp3+ T cell number is a strong prognostic factor independent of classical risk factors such as tobacco, alcohol, and HPV status. Conclusion: Foxp3+ T cell number is a significant prognostic factor for HNSCC, improving the tumor stage, and that viral E7 may play a role in the Foxp3+ T cell infiltration to the tumor.
Journal of Clinical Medicine, Jan 6, 2017
Transforming growth factor-β (TGF-β) is an intriguing cytokine exhibiting dual activities in mali... more Transforming growth factor-β (TGF-β) is an intriguing cytokine exhibiting dual activities in malignant disease. It is an important mediator of cancer invasion, metastasis and angiogenesis, on the one hand, while it exhibits anti-tumor functions on the other hand. Elucidating the precise role of TGF-β in malignant development and progression requires a better understanding of the molecular mechanisms involved in its tumor suppressor to tumor promoter switch. One important aspect of TGF-β function is its interaction with proteins within the tumor microenvironment. Several stromal proteins have the natural ability to interact and modulate TGF-β function. Understanding the complex interplay between the TGF-β signaling network and these stromal proteins may provide greater insight into the development of novel therapeutic strategies that target the TGF-β axis. The present review highlights our present understanding of how stroma modulates TGF-β activity in human cancers.
Oncotarget, Jan 24, 2018
Incidence of human papillomavirus (HPV)-related head and neck squamous cell carcinomas (HNSCCs) h... more Incidence of human papillomavirus (HPV)-related head and neck squamous cell carcinomas (HNSCCs) has increased over the last few decades. The reaction of the host immune system to these tumors remains biologically complex. Here, we investigated CD68+ macrophage numbers, reporting the prognostic value in comparison to other risk factors. We also examined CD68+ macrophage infiltration during disease progression regarding the impact of HPV infection, and we studied the role of HPV16-E6/E7 oncoproteins in CD68+ macrophage recruitment. CD68+ macrophage numbers were evaluated in 10 cases of tumor-free peri-tumoral epithelia, 43 cases of low-grade dysplasia, 45 cases of high-grade dysplasia and 110 cases of carcinoma. Our in vivo model was developed in 80 C3H/HeN mice orthotopically injected with HPV16-E6,-E7 or-E6/E7-transfected SCC-VII cell lines. High CD68+ macrophage numbers in the intra-tumoral compartment were associated with shorter patient survival (recurrence-free survival: p = 0.001; overall survival: p = 0.01). Multivariate analyses reported that CD68+ macrophage infiltration and tumor stage were strong and independent prognostic factors of HNSCC. CD68+ macrophage numbers increased during HNSCC progression both in intra-epithelial (p < 0.001) and stromal compartments (p < 0.001). A higher density of CD68+ macrophages was observed in advanced stages (p = 0.004). Patients with transcriptionally active HPV infections had higher CD68+ macrophage density than did HPV-negative patients (p = 0.003). CD68+ macrophage infiltration was higher in HPV-E7+ and −E6/E7+ mouse tumors than in-E6+ tumors (p = 0.029 and p < 0.001). In conclusion, the extent of CD68+ macrophage infiltration is a significant prognostic factor for HNSCC patients. The recruitment of macrophages increases during disease progression and is influenced by the HPV virus.
Oncogene, Dec 15, 2017
Cancer research is increasingly dependent of patient-derived xenograft model (PDX). However, a ma... more Cancer research is increasingly dependent of patient-derived xenograft model (PDX). However, a major point of concern regarding the PDX model remains the replacement of the human stroma with murine counterpart. In the present work we aimed at clarifying the significance of the human-to-murine stromal replacement for the fidelity of colorectal cancer (CRC) and liver metastasis (CRC-LM) PDX model. We have conducted a comparative metabolic analysis between 6 patient tumors and corresponding PDX across 4 generations. Metabolic signatures of cancer cells and stroma were measured separately by MALDI-imaging, while metabolite changes in entire tumors were quantified using mass spectrometry approach. Measurement of glucose metabolism was also conducted in vivo using [ 18 F]-fluorodeoxyglucose (FDG) and positron emission tomography (PET). In CRC/CRC-LM PDX model, human stroma was entirely replaced at the second generation. Despite this change, MALDI-imaging demonstrated that the metabolic profiles of both stromal and cancer cells remained stable for at least four generations in comparison to the original patient material. On the tumor level, profiles of 86 watersoluble metabolites as well as 93 lipid mediators underlined the functional stability of the PDX model. In vivo PET measurement of glucose uptake (reflecting tumor glucose metabolism) supported the ex vivo observations. Our data show for the first time that CRC/CRC-LM PDX model maintains the functional stability at the metabolic level despite the early replacement of the human stroma by murine cells. The findings demonstrate that human cancer cells actively educate murine stromal cells during PDX development to adopt the human-like phenotype.
Scientific Reports, Sep 15, 2017
Metabolic reprogramming toward aerobic glycolysis unavoidably favours methylglyoxal (MG) and adva... more Metabolic reprogramming toward aerobic glycolysis unavoidably favours methylglyoxal (MG) and advanced glycation end products (AGEs) formation in cancer cells. MG was initially considered a highly cytotoxic molecule with potential anti-cancer value. However, we have recently demonstrated that MG enhanced tumour growth and metastasis. In an attempt to understand this dual role, we explored MGmediated dicarbonyl stress status in four breast and glioblastoma cancer cell lines in relation with their glycolytic phenotype and MG detoxifying capacity. In glycolytic cancer cells cultured in high glucose, we observed a significant increase of the conversion of MG to D-lactate through the glyoxalase system. Moreover, upon exogenous MG challenge, glycolytic cells showed elevated amounts of intracellular MG and induced de novo GLO1 detoxifying enzyme and Nrf2 expression. Thus, supporting the adaptive nature of glycolytic cancer cells to MG dicarbonyl stress when compared to non-glycolytic ones. Finally and consistent with the pro-tumoural role of MG, we showed that low doses of MG induced AGEs formation and tumour growth in vivo, both of which can be reversed using a MG scavenger. Our study represents the first demonstration of a hormetic effect of MG defined by a low-dose stimulation and a high-dose inhibition of tumour growth.
Oncogene, May 3, 2018
Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related death. Thera... more Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related death. Therapeutic options remain very limited and are based on classical chemotherapies. Energy metabolism reprogramming appears as an emerging hallmark of cancer and is considered a therapeutic target with considerable potential. Myoferlin, a ferlin family member protein overexpressed in PDAC, is involved in plasma membrane biology and has a tumor-promoting function. In the continuity of our previous studies, we investigated the role of myoferlin in the context of energy metabolism in PDAC. We used selected PDAC tumor samples and PDAC cell lines together with small interfering RNA technology to study the role of myoferlin in energetic metabolism. In PDAC patients, we showed that myoferlin expression is negatively correlated with overall survival and with glycolytic activity evaluated by 18 F-deoxyglucose positron emission tomography. We found out that myoferlin is more abundant in lipogenic pancreatic cancer cell lines and is required to maintain a branched mitochondrial structure and a high oxidative phosphorylation activity. The observed mitochondrial fission induced by myoferlin depletion led to a decrease of cell proliferation, ATP production, and autophagy induction, thus indicating an essential role of myoferlin for PDAC cell fitness. The metabolic phenotype switch generated by myoferlin silencing could open up a new perspective in the development of therapeutic strategies, especially in the context of energy metabolism.
International Journal of Cancer, Mar 28, 2019
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Papers by Justine Bellier