Project description:Breast tumors develop in a complex microenvironment whose main component is adipose tissue and gain aggressiveness through increased fatty acid uptake. Here, we demonstrated that palmitic acid (PA) induced ferroptosis in triple negative breast cancers (TNBC). We found that PA increases the protein expression levels of the long-chain fatty acid transporter CD36 leading to increased lipid uptake. Mechanistically, overexpression of CD36 increases lipid peroxidation, mitochondrial ROS production, the labile iron pool and especially Fe2+ content. Additionally, we found increased expression of ferroptotic target genes (HMOX1, ACSL1, SAT1) and decreased of anti-ferroptotic genes (GPX4 and FSP1) in TNBC following PA exposure. Overexpression of CD36 did not induce ferroptosis in estrogen receptor positive breast cancer. Clinically, higher CD36 expression correlated with the luminal androgen receptor (LAR) subtype of TNBC, known to exhibit a higher sensitivity to ferroptosis. Altogether, these data provide evidence for an essential role of the CD36 protein in the ferroptotic process induced by the saturated fatty acid PA, opening potential new therapeutic approaches promoting ferroptosis in the most aggressive breast cancers.
Project description:Metastasis is the leading cause of cancer-related deaths. For most human cancers, the identity of the cells that initiate and promote metastasis is still unknown, hampering our ability to develop therapies to prevent or inhibit the spread of tumour cells to distant sites. Using an orthotopic model of human oral squamous cell carcinoma (OSCC), we have now identified a subpopulation of CD44bright cells within the primary lesion with the highest potential to develop lymph node and lung metastasis. This population is slow-cycling, expresses high levels of the receptor CD36 at the cell membrane and relies on fatty acid metabolism to thrive in lymph nodes and bronchoalveolar environments. Importantly, inhibition of CD36 by either shRNA or neutralizing monoclonal antibodies severely impairs metastatic spread of primary OSCC patient samples and established cell lines. Further underscoring its importance, CD36 overexpression in poorly disseminating tumours confers an aggressive metastatic behaviour. Analyses of public gene expression data indicate that the presence of the signature-defining CD36+ cells also strongly correlates with a poor prognosis in patients with lung SCC, ovarian cancer, bladder cancer, or luminal breast cancer. By identifying metastasis-promoting cells and then targeting them with CD36 inhibition, novel anti-metastatic therapies could be developed for patients with these types of tumours.
Project description:Metastasis is the leading cause of cancer-related deaths. For most human cancers, the identity of the cells that initiate and promote metastasis is still unknown, hampering our ability to develop therapies to prevent or inhibit the spread of tumour cells to distant sites. Using an orthotopic model of human oral squamous cell carcinoma (OSCC), we have now identified a subpopulation of CD44bright cells within the primary lesion with the highest potential to develop lymph node and lung metastasis. This population is slow-cycling, expresses high levels of the receptor CD36 at the cell membrane and relies on fatty acid metabolism to thrive in lymph nodes and bronchoalveolar environments. Importantly, inhibition of CD36 by either shRNA or neutralizing monoclonal antibodies severely impairs metastatic spread of primary OSCC patient samples and established cell lines. Further underscoring its importance, CD36 overexpression in poorly disseminating tumours confers an aggressive metastatic behaviour. Analyses of public gene expression data indicate that the presence of the signature-defining CD36+ cells also strongly correlates with a poor prognosis in patients with lung SCC, ovarian cancer, bladder cancer, or luminal breast cancer. By identifying metastasis-promoting cells and then targeting them with CD36 inhibition, novel anti-metastatic therapies could be developed for patients with these types of tumours.
Project description:Metastasis is the leading cause of cancer-related deaths. For most human cancers, the identity of the cells that initiate and promote metastasis is still unknown, hampering our ability to develop therapies to prevent or inhibit the spread of tumour cells to distant sites. Using an orthotopic model of human oral squamous cell carcinoma (OSCC), we have now identified a subpopulation of CD44bright cells within the primary lesion with the highest potential to develop lymph node and lung metastasis. This population is slow-cycling, expresses high levels of the receptor CD36 at the cell membrane and relies on fatty acid metabolism to thrive in lymph nodes and bronchoalveolar environments. Importantly, inhibition of CD36 by either shRNA or neutralizing monoclonal antibodies severely impairs metastatic spread of primary OSCC patient samples and established cell lines. Further underscoring its importance, CD36 overexpression in poorly disseminating tumours confers an aggressive metastatic behaviour. Analyses of public gene expression data indicate that the presence of the signature-defining CD36+ cells also strongly correlates with a poor prognosis in patients with lung SCC, ovarian cancer, bladder cancer, or luminal breast cancer. By identifying metastasis-promoting cells and then targeting them with CD36 inhibition, novel anti-metastatic therapies could be developed for patients with these types of tumours.
Project description:Metastasis is the leading cause of cancer-related deaths. For most human cancers, the identity of the cells that initiate and promote metastasis is still unknown, hampering our ability to develop therapies to prevent or inhibit the spread of tumour cells to distant sites. Using an orthotopic model of human oral squamous cell carcinoma (OSCC), we have now identified a subpopulation of CD44bright cells within the primary lesion with the highest potential to develop lymph node and lung metastasis. This population is slow-cycling, expresses high levels of the receptor CD36 at the cell membrane and relies on fatty acid metabolism to thrive in lymph nodes and bronchoalveolar environments. Importantly, inhibition of CD36 by either shRNA or neutralizing monoclonal antibodies severely impairs metastatic spread of primary OSCC patient samples and established cell lines. Further underscoring its importance, CD36 overexpression in poorly disseminating tumours confers an aggressive metastatic behavior. Analyses of public gene expression data indicate that the presence of the signature-defining CD36+ cells also strongly correlates with a poor prognosis in patients with lung SCC, ovarian cancer, bladder cancer, or luminal breast cancer. By identifying metastasis-promoting cells and then targeting them with CD36 inhibition, novel anti-metastatic therapies could be developed for patients with these types of tumours.
Project description:The prognosis of non-small cell lung cancer (NSCLC) with leptomeningeal metastases (LM) is dismal. The regulators of LM progression remain elusive, thus impeding effective clinical intervention. Here, we performed in vivo genome-wide CRISPR-based screens and discovered that Fused in sarcoma (FUS) ablation promoted LM in both PC9 and A549 cell lines. FUS repressed CD36 expression by directly interacting with and destabilizing PPARA mRNA. CD36 augmented fatty acid uptake and oxidative phosphorylation in NSCLC cells. Matrix metallopeptidase 2 (MMP2) was upregulated through CD36-mediated fatty acid metabolism, which enabled NSCLC cells to disrupt the endothelial barrier. FUS-deficient NSCLC cells increased the expression of neuroendocrine differentiation (NED) related markers, including SRY-box transcription factor 2 (SOX2), microtubule associated protein 2 (MAP2), enolase 2 (NSE) and synaptophysin (SYP), exhibited neurite-like extensions, and expanded robustly in cerebrospinal fluid-supplemented medium through a CD36-dependent manner. Mechanistically, fatty acid uptake increased acetyl-CoA and H3K27ac modifications to promote the expression of NED signature genes and MMP2 in NSCLC cells. Genetic or pharmacological inhibition of CD36, or inhibition of NED signature in NSCLC cells hindered LM and prolonged survival in mice. In patients with NSCLC, FUS downregulation and CD36 or SYP upregulation were associated with aggressive LM progression. Thus, CD36-mediated fatty acid metabolism and NED signature are crucial for LM progression in NSCLC, highlighting CD36 as a potential LM biomarker and a promising therapeutic target for LM treatment.