Primary cilia are increasingly recognized as regulators of cellular signaling and plasticity. Here, we examined their distribution and potential relevance in neuroendocrine (NE) prostate cancer. While typically absent in localized hormone-sensitive prostate tumor cells, we detected primary cilia in neuroendocrine-like cells both in vitro and in castration-resistant prostate cancer (CRPC) samples. In vivo, cilia were consistently observed in CRPC tumor cells exhibiting FDG-PET positivity and NE features, supporting an association between ciliogenesis, metabolic reprogramming, and disease progression. These aggressive tumors also displayed reduced mitochondrial activity, consistent with a shift away from oxidative metabolism. Building on our work in ccRCC, we identified a GLI1⁺/IFT20⁺ or GLI1⁺/IFT80⁺ signature enriched in ciliated, NE-prone subpopulations. In vitro, YAP1 inhibition alone did not induce ciliogenesis, whereas cytoskeletal remodeling with jasplakinolide restored cilium assembly and enabled partial NE transdifferentiation. Single-cell RNA-seq analyses further showed enrichment of ciliogenesis-related genes within NE clusters in CRPC. Together, these observations support a model in which primary cilia are closely associated with NE identity and metabolic adaptation, rather than serving solely as passive markers, and suggest a structural-metabolic axis that may represent a source of biomarkers and therapeutic vulnerabilities.

Protein synthesis plays a central role in cancer development and progression. eukaryotic initiation factor 5 A (eIF5A), a translation factor activated by hypusination, is implicated in tumorigenesis, however, its mode of action is still unclear. We find that hypusinated eIF5A (eIF5Ahyp) promotes metastasis and tumor growth in prostate cancer (PCa) by supporting mitochondrial metabolism and translation. eIF5Ahyp controls the subcellular localization of Mitochondrial Ribonuclease P Protein 3 (MRPP3) mRNA encoding a protein essential for mitochondrial tRNA (mt-tRNA) maturation. We show that eIF5Ahyp regulates the nuclear export of MRPP3 mRNA, its expression, thereby promoting mt-tRNA maturation. Our findings establish that MRPP3 enhances mitochondrial metabolism and supports PCa metastasis. Importantly, its expression restores mitochondrial translation and tumor growth inhibited by the downregulation of eIF5Ahyp. Together, we uncover a critical role for eIF5Ahyp in mitochondrial protein synthesis and highlight its broader implications in coordinating the expression of nuclear and mitochondrial genomes, linking hypusination to cancer progression.

eIF5A is a translation factor dysregulated in several pathologies such as cancer and diabetes. eIF5A activity depends upon its hypusination, a unique post-translational modification catalyzed by two enzymes: DHPS and DOHH. Only a few molecules able to inhibit hypusination have been described, and none are used for the treatment of patients. The scarcity of new inhibitors is probably due to the challenge of measuring DHPS and DOHH activities. Here, we describe the Hyp'Assay, a convenient cell-free assay to monitor eIF5A hypusination. Hypusination is performed in 96-well plates using recombinant human eIF5A, DHPS, and DOHH and is revealed by an antibody against hypusinated eIF5A. Pharmacological values obtained with the Hyp'Assay, such as the EC50 of DHPS for spermidine or the IC50 of GC7 for DHPS, were similar to published data, supporting the reliability of the Hyp'Assay. As a proof of concept, we synthesized four new GC7 analogs and showed, using the Hyp'Assay, that these derivatives inhibit hypusination. In summary, we present the Hyp'Assay; a reliable and sensitive assay for new hypusination inhibitors. This assay could be of interest to researchers wanting an easier way to study hypusination, and also a valuable tool for large-scale screening of chemical libraries for new hypusination inhibitors.

Prostate cancer is the archetypal hormone-dependent cancer in men, mirroring breast cancer in women. The increase in its prevalence over time raises questions, and occupational exposure data, particularly among agricultural workers, have shown a probable or possible link with exposure to certain endocrine disruptors. The best-known of these is probably chlordecone, used in the French West Indies and responsible for an increased risk of prostate cancer. Outside these situations of occupational and/or acute exposure, it is more difficult to prove that endocrine disruptors are responsible for prostate cancer, particularly through epidemiological studies, the interpretation of which is still difficult. Animal models, in particular murine models, have demonstrated the role of fetal or early neonatal exposure in the development of prostate cancer in adulthood. In vitro models, meanwhile, are shedding light on the mechanisms involved in tumor promotion and progression, involving both classic hormone receptors (AR, ER) and other new signaling pathways. The aim of this review is to report the available data showing the link between exposure to endocrine disruptors and the risk of prostate cancer.

Abstract Background The metabolism of cancer cells generally differs from that of normal cells. Indeed, most cancer cells have a high rate of glycolysis, even at normal oxygen concentrations. These metabolic properties can potentially be exploited for therapeutic intervention. In this context, we have developed troglitazone derivatives to treat hormone-sensitive and triple-negative breast cancers, which currently lack therapeutic targets, have an aggressive phenotype, and often have a worse prognosis than other subtypes. Here, we studied the metabolic impact of the EP13 compound, a desulfured derivative of Δ2-troglitazone that we synthetized and is more potent than its parent compounds. Methods EP13 was tested on two triple-negative breast cancer cell lines, MDA-MB-231 and Hs578T, and on the luminal cell line MCF-7. The oxygen consumption rate (OCR) of the treated cell lines, Hs578T mammospheres and isolated mitochondria was measured using the XFe24 Seahorse analyser. ROS production was quantified using the MitoSOX fluorescent probe. Glycolytic activity was evaluated through measurement of the extracellular acidification rate (ECAR), glucose consumption and lactate production in extracellular medium. The synergistic effect of EP13 with glycolysis inhibitors (oxamate and 2-deoxyglucose) on cell cytotoxicity was established using the Chou-Talalay method. Results After exposure to EP13, we observed a decrease in the mitochondrial oxygen consumption rate in MCF7, MDA-MB-231 and Hs578T cells. EP13 also modified the maximal OCR of Hs578T spheroids. EP13 reduced the OCR through inhibition of respiratory chain complex I. After 24 h, ATP levels in EP13-treated cells were not altered compared with those in untreated cells, suggesting compensation by glycolysis activity, as shown by the increase in ECAR, the glucose consumption and lactate production. Finally, we performed co-treatments with EP13 and glycolysis inhibitors (oxamate and 2-DG) and observed that EP13 potentiated their cytotoxic effects. Conclusion This study demonstrates that EP13 inhibits OXPHOS in breast cancer cells and potentiates the effect of glycolysis inhibitors.

BACKGROUND:Prostate cancer (PCa) ranks as the second most prevalent cancer in men, with advanced stages posing significant treatment challenges. Given its solid tumor nature, PCa is highly susceptible to hypoxia, a condition associated with resistance to radiation and chemotherapy, metastasis, and unfavorable patient outcomes. Hypoxia-inducible factors (HIFs) play a pivotal role in cancer cell adaptation to hypoxic environments, contributing to treatment resistance. Consequently, inhibitors targeting HIFs hold promise for cancer therapy. METHODS:In this study, we aimed to characterize novel HIF-1α inhibitors including Sodwanones A (1), B (2), C (3), G (4) and Yardenone 2 (5) isolated from marine sponges belonging to the Axinella genus. Our investigation evaluated the impact of these compounds on various aspects of HIF-1α regulation, including stabilization, nuclear localization, expression of HIF-1 target genes (while sparing HIF-2 target genes), cellular metabolism, as well as cell proliferation and viability in prostate cells under hypoxic conditions. RESULTS:Our findings revealed that among the compounds tested, Yardenone 2 exhibited notable effects in hypoxia: it destabilized HIF-1α at the protein level, decreased its nuclear localization, selectively altered the expression of HIF-1 target genes, and restrained cell proliferation in aggressive PC3 prostate cancer cells as well as in an MSK-PCa3 patient-derived organoid line. Moreover, it affected the morphology of these organoid. Yardenone 2 was also compared to Docetaxel, a specific microtubule inhibitor and a drug used in the treatment of prostate cancer. The comparison between the two compounds revealed notable differences, such as a lack of specificity to hypoxic cells of Docetaxel. CONCLUSION:These results mark the first demonstration that Yardenone 2 functions as a cytostatic-like inhibitor impacting microtubules, specifically targeting hypoxic cancer cells. This discovery suggests a promising avenue for novel therapeutic interventions in prostate cancer.

Metformin and IACS-010759 are two distinct antimetabolic agents. Metformin, an established antidiabetic drug, mildly inhibits mitochondrial complex I, while IACS-010759 is a new potent mitochondrial complex I inhibitor. Mitochondria is pivotal in the energy metabolism of cells by providing adenosine triphosphate through oxidative phosphorylation (OXPHOS). Hence, mitochondrial metabolism and OXPHOS become a vulnerability when targeted in cancer cells. Both drugs have promising antitumoral effects in diverse cancers, supported by preclinical in vitro and in vivo studies. We present evidence of their direct impact on cancer cells and their immunomodulatory effects. In clinical studies, while observational epidemiologic studies on metformin were encouraging, actual trial results were not as expected. However, IACS-01075 exhibited major adverse effects, thereby causing a metabolic shift to glycolysis and elevated lactic acid concentrations. Therefore, the future outlook for these two drugs depends on preventive clinical trials for metformin and investigations into the plausible toxic effects on normal cells for IACS-01075.

The primary cilium, a non-motile organelle present in most human cells, plays a crucial role in detecting microenvironmental changes and regulating intracellular signaling. Its dysfunction is linked to various diseases, including cancer. We explored the role of ciliated cells in prostate cancer by using Gefitinib and Jasplakinolide compounds to induce ciliated cells in both normal and tumor-like prostate cell lines. We assessed GLI1 and IFT20 expression and investigated YAP1 protein's role, which is implicated in primary cilium regulation. Finally, we examined these compounds in 3D cell models, aiming to simulate in vivo conditions. Our study highlights YAP1 as a potential target for novel genetic models to understand the primary cilium's role in mediating resistance to anticancer treatments.

Benign prostate hyperplasia (BPH) is caused by the nonmalignant enlargement of the transition zone of the prostate gland, leading to lower urinary tract symptoms. Although current medical treatments are unsatisfactory in many patients, the limited understanding of the mechanisms driving disease progression prevents the development of alternative therapeutic strategies. The probasin-prolactin (Pb-PRL) transgenic mouse recapitulates many histopathological features of human BPH. Herein, these alterations parallel urodynamic disturbance reminiscent of lower urinary tract symptoms. Single-cell RNA-sequencing analysis of Pb-PRL mouse prostates revealed that their epithelium mainly includes low-androgen signaling cell populations analogous to Club/Hillock cells enriched in the aged human prostate. These intermediate cells are predicted to result from the reprogramming of androgen-dependent luminal cells. Pb-PRL mouse prostates exhibited increased vulnerability to oxidative stress due to reduction of antioxidant enzyme expression. One-month treatment of Pb-PRL mice with anethole trithione (ATT), a specific inhibitor of mitochondrial ROS production, reduced prostate weight and voiding frequency. In human BPH-1 epithelial cells, ATT decreased mitochondrial metabolism, cell proliferation, and stemness features. ATT prevented the growth of organoids generated by sorted Pb-PRL basal and LSCmed cells, the two major BPH-associated, androgen-independent epithelial cell compartments. Taken together, these results support cell plasticity as a driver of BPH progression and therapeutic resistance to androgen signaling inhibition, and identify antioxidant therapy as a promising treatment of BPH.

Cancer metabolic reprogramming has been recognized as one of the cancer hallmarks that promote cell proliferation, survival, as well as therapeutic resistance. Up-to-date regulation of metabolism in T-cell lymphoma is poorly understood. In particular, for human angioimmunoblastic T-cell lymphoma (AITL) the metabolic profile is not known. Metabolic intervention could help identify new treatment options for this cancer with very poor outcomes and no effective medication. Transcriptomic analysis of AITL tumor cells, identified that these cells use preferentially mitochondrial metabolism. By using our preclinical AITL mouse model, mimicking closely human AITL features, we confirmed that T follicular helper (Tfh) tumor cells exhibit a strong enrichment of mitochondrial metabolic signatures. Consistent with these results, disruption of mitochondrial metabolism using metformin or a mitochondrial complex I inhibitor such as IACS improved the survival of AITL lymphoma-bearing mice. Additionally, we confirmed a selective elimination of the malignant human AITL T cells in patient biopsies upon mitochondrial respiration inhibition. Moreover, we confirmed that diabetic patients suffering from T-cell lymphoma, treated with metformin survived longer as compared to patients receiving alternative treatments. Taking together, our findings suggest that targeting the mitochondrial metabolic pathway could be a clinically efficient approach to inhibit aggressive cancers such as peripheral T-cell lymphoma.

Medulloblastoma (MB) is the most prevalent brain cancer in children. Four subgroups of MB have been identified; of these, Group 3 is the most metastatic. Its genetics and biology remain less clear than the other groups, and it has a poor prognosis and few effective treatments available. Tumor hypoxia and the resulting metabolism are known to be important in the growth and survival of tumors but, to date, have been only minimally explored in MB. Here we show that Group 3 MB tumors do not depend on the canonical transcription factor hypoxia-inducible factor-1α (HIF-1α) to mount an adaptive response to hypoxia. We discovered that HIF-1α is rendered inactive either through post-translational methylation, preventing its nuclear localization specifically in Group 3 MB, or by a low expression that prevents modulation of HIF-target genes. Strikingly, we found that HIF-2 takes over the role of HIF-1 in the nucleus and promotes the activation of hypoxia-dependent anabolic pathways. The exclusion of HIF-1 from the nucleus in Group 3 MB cells enhances the reliance on HIF-2's transcriptional role, making it a viable target for potential anticancer strategies. By combining pharmacological inhibition of HIF-2α with the use of metformin, a mitochondrial complex I inhibitor to block respiration, we effectively induced Group 3 MB cell death, surpassing the effectiveness observed in Non-Group 3 MB cells. Overall, the unique dependence of MB cells, but not normal cells, on HIF-2-mediated anabolic metabolism presents an appealing therapeutic opportunity for treating Group 3 MB patients with minimal toxicity.

Increasing evidence points towards a causal link between exposure to persistent organic pollutants (POPs) with increased incidence and aggressivity of various cancers. Among these POPs, dioxin and PCB-153 are widely found in our environment and represent a significant source of contamination. Dioxin exposure has already been linked to cancer such as non-Hodgkin’s lymphoma, but remains to be more extensively investigated in other cancers. Potential implications of dioxin and PCB-153 in prostate cancer progression spurred us to challenge both ex vivo and in vivo models with low doses of these POPs. We found that dioxin or PCB-153 exposure increased hallmarks of growth and metastasis of prostate cancer cells ex vivo and in grafted NOD-SCID mice. Exposure induced histopathological carcinoma-like patterns in the Pten pc−/− mice. We identified up-regulation of Acetyl-CoA Acetyltransferase-1 (ACAT1) involved in ketone bodies pathway as a potential target. Mechanistically, genetic inhibition confirmed that ACAT1 mediated dioxin effect on cell migration. Using public prostate cancer datasets, we confirmed the deregulation of ACAT1 and associated gene encoded ketone bodies pathway enzymes such as OXCT1 , BDH1 and HMGCL in advanced prostate cancer. To further explore this link between dioxin and ACAT1 deregulation, we analyzed a unique prostate-tumour tissue collection from the USA veterans exposed to agent orange, known to be highly contaminated by dioxin because of industrial production. We found that ACAT1 histoscore is significantly increased in exposed patients. Our studies reveal the implication of dioxin and PCB-153 to induce a prometastatic programme in prostate tumours and identify ACAT1 deregulation as a key event in this process.

PGC-a regulates c-MYC and ODC1 expression

Supplementary Figure 1 from Targeting Cancer Cell Metabolism: The Combination of Metformin and 2-Deoxyglucose Induces p53-Dependent Apoptosis in Prostate Cancer Cells

Le médulloblastome est une tumeur maligne cérébrale qui touche principalement les enfants. Elle est rarement retrouvée chez l’adulte. Parmi les quatre groupes de médulloblastome définis aujourd’hui selon des caractéristiques moléculaires, le groupe 3 est le moins favorable avec un taux de survie globale de 50 %. Les traitements actuels, basés sur la chirurgie, la radiothérapie et la chimiothérapie, ne sont pas suffisamment adaptés aux différentes caractéristiques des quatre groupes de médulloblastome. Cependant, l’utilisation de nouveaux modèles cellulaires et animaux a ouvert de nouvelles portes vers des voies thérapeutiques intéressantes. Dans cette revue, nous détaillons les progrès récents de la recherche sur le médulloblastome, en mettant l’accent sur les gènes et les voies qui dirigent la tumorigenèse et, plus particulièrement, sur les modèles animaux qui ont été développés pour étudier la biologie des tumeurs, ainsi que les progrès des nouvelles thérapies ciblées.

Supplementary Figures 1-3 from Metformin, Independent of AMPK, Induces mTOR Inhibition and Cell-Cycle Arrest through REDD1

Medulloblastoma is a cancerous brain tumor that affects mostly children. Among the four groups defined by molecular characteristics, Group 3, the least well characterized, is also the least favorable, with a survival rate of 50%. Current treatments, based on surgery, radiotherapy, and chemotherapy, are not adequate and the lack of understanding of the different molecular features of Group 3 tumor cells makes the development of effective therapies challenging. In this study, the problem of medulloblastoma is approached from a metabolic standpoint in a low oxygen microenvironment. We establish that Group 3 cells use both the mitochondrial glycerol-3 phosphate (G3PS) and malate-aspartate shuttles (MAS) to produce NADH. Small molecules that target G3PS and MAS show a greater ability to decrease cell proliferation and induce apoptosis specifically of Group 3 cells. In addition, as Group 3 cells show improved respiration in hypoxia, the use of Phenformin, a mitochondrial complex 1 inhibitor, alone or in combination, induced significant cell death. Furthermore, inhibition of the cytosolic NAD+ recycling enzyme lactate dehydrogenase A (LDHA), enhanced the effects of the NADH shuttle inhibitors. In a 3D model using Group 3 human cerebellar organoids, tumor cells also underwent apoptosis upon treatment with NADH shuttle inhibitors. Our study demonstrates metabolic heterogeneity depending on oxygen concentrations and provides potential therapeutic solutions for patients in Group 3 whose tumors are the most aggressive.

Diabetes mellitus is a major public health problem in all countries due to its high human and economic burden. Major metabolic alterations are associated with the chronic hyperglycemia that characterizes diabetes and causes devastating complications, including retinopathy, kidney failure, coronary disease and increased cardiovascular mortality. The most common form is type 2 diabetes (T2D) accounting for 90 to 95% of the cases. These chronic metabolic disorders are heterogeneous to which genetic factors contribute, but so do prenatal and postnatal life environmental factors including a sedentary lifestyle, overweight, and obesity. However, these classical risk factors alone cannot explain the rapid evolution of the prevalence of T2D and the high prevalence of type 1 diabetes in particular areas. Among environmental factors, we are in fact exposed to a growing amount of chemical molecules produced by our industries or by our way of life. In this narrative review, we aim to give a critical overview of the role of these pollutants that can interfere with our endocrine system, the so-called endocrine-disrupting chemicals (EDCs), in the pathophysiology of diabetes and metabolic disorders.