Project description:Cancer-associated fibroblasts (CAFs) are one of the most prominent and active components in the pancreatic tumor microenvironment. Our data show that CAFs are critical for PDAC survival upon glutamine deprivation. Specifically, we uncovered a role for nucleosides, which are secreted by CAFs through autophagy in an NUFIP1-depenent manner, increased glucose utilization and promoted growth of PDAC. Moreover, we demonstrate that CAF-derived nucleosides induced glucose consumption under glutamine-deprived conditions and displayed a dependence on MYC. Using an orthotopic mouse model of PDAC, we found that inhibiting nucleoside secretion by targeting NUFIP1 in the stroma reduced tumor weight. This finding highlights a previously unappreciated metabolic network within pancreatic tumors in which diverse nutrients are used to promote growth in an austere tumor microenvironment.
Project description:There are two major subtype of cells in breast cancer. These cancer cells response differently to glutamine deprivation, here we use one luminal type of breast cancer cell (MCF7) and one basal type of breast cancer cell (MDAMB231) to compare the gene expression differences of these two types of cancer cells in glutamine deprivation. Many cancer cells depend on glutamine for survival and oncogenic transformation. Although targeting glutamine metabolism is proposed as novel therapies, their heterogeneity among different tumors is unknown. Here, we found only basal-type, but not luminal-type breast cancer cells, exhibited phenotypes of glutamine dependency and may benefit from glutamine-targeting therapeutics. The glutamine independence of luminal-type cells is caused by the specific expression of glutamine synthetase (GS), a pattern recapitulated in luminal breast cancers. The co-culture of luminal cells partially rescued the basal cells under glutamine deprivation, suggesting glutamine symbiosis. The luminal-specific expression of GS is directly induced GATA3 and down-regulates glutaminase expression to maintain subtype-specific glutamine metabolism. Collectively, these data indicate the distinct glutamine phenotypes among breast cells and enable the rational design of glutamine targeted therapies. Gene expression analysis in MCF7 and MDAMB231 cultured with or without glutamine for 24h
Project description:There are two major subtype of cells in breast cancer. These cancer cells response differently to glutamine deprivation, here we use one luminal type of breast cancer cell (MCF7) and one basal type of breast cancer cell (MDAMB231) to compare the gene expression differences of these two types of cancer cells in glutamine deprivation. Many cancer cells depend on glutamine for survival and oncogenic transformation. Although targeting glutamine metabolism is proposed as novel therapies, their heterogeneity among different tumors is unknown. Here, we found only basal-type, but not luminal-type breast cancer cells, exhibited phenotypes of glutamine dependency and may benefit from glutamine-targeting therapeutics. The glutamine independence of luminal-type cells is caused by the specific expression of glutamine synthetase (GS), a pattern recapitulated in luminal breast cancers. The co-culture of luminal cells partially rescued the basal cells under glutamine deprivation, suggesting glutamine symbiosis. The luminal-specific expression of GS is directly induced GATA3 and down-regulates glutaminase expression to maintain subtype-specific glutamine metabolism. Collectively, these data indicate the distinct glutamine phenotypes among breast cells and enable the rational design of glutamine targeted therapies.
Project description:Metabolic reprogramming is a hallmark of human cancer and cancer-specific metabolism provide opportunities for cancer diagnosis, prognosis, and treatment. However, how metabolic pathways affect the initiation and progression of colorectal cancer remain largely unknown. Here, we showed cysteine is highly enriched in colorectal tumors compared with adjacent non-tumor tissues to promote tumorigenesis of CRC. Both cystine and cysteine imports are essential to maintain intracellular cysteine level and promote tumor growth and survival. Transporter genes of cystine and cysteine are all upregulated in colorectal cancer by tumor microenvironment induced ROS through transcription factor ATF4. Glutathione synthetase GSS is upregulated and increases cysteine to reduced glutathione flux to support tumor growth and survival in colorectal cancer. Depletion of cystine and cysteine by a recombinant cyst(e)inase effectively reduced the growth of colorectal tumors. Moreover, scavenging cystine and cysteine induces autophagy of colorectal cancer cells through mTOR-ULK signaling axis. With this study, we demonstrate that cysteine metabolism is a key signature of CRC metabolic reprogramming and targeting cysteine metabolism might be an effective approach to treat colon cancer.
Project description:Metabolic reprogramming is a hallmark of human cancer and cancer-specific metabolism provide opportunities for cancer diagnosis, prognosis, and treatment. However, how metabolic pathways affect the initiation and progression of colorectal cancer remain largely unknown. Here, we showed cysteine is highly enriched in colorectal tumors compared with adjacent non-tumor tissues to promote tumorigenesis of CRC. Both cystine and cysteine imports are essential to maintain intracellular cysteine level and promote tumor growth and survival. Transporter genes of cystine and cysteine are all upregulated in colorectal cancer by tumor microenvironment induced ROS through transcription factor ATF4. Glutathione synthetase GSS is upregulated and increases cysteine to reduced glutathione flux to support tumor growth and survival in colorectal cancer. Depletion of cystine and cysteine by a recombinant cyst(e)inase effectively reduced the growth of colorectal tumors. Moreover, scavenging cystine and cysteine induces autophagy of colorectal cancer cells through mTOR-ULK signaling axis. With this study, we demonstrate that cysteine metabolism is a key signature of CRC metabolic reprogramming and targeting cysteine metabolism might be an effective approach to treat colon cancer.
Project description:Glutamine metabolism in the tumor microenvironment is emerging as a critical regulator of immune-mediated anti-tumor responses. We report potent tumor growth inhibition by the glutamine antagonist prodrug JHU083 in urologic tumors by JHU083-reprogrammed tumor-associated macrophages (TAMs) and tumor-infiltrating monocytes (TIMs). Using orthogonal approaches, we show that JHU083-mediated glutamine antagonism in the tumor microenvironment induces TNF, inflammatory, and mTORC1 signaling in different intra-tumoral TAM clusters. Additionally, we report that JHU083 increases proliferation in tissue-resident macrophages intratumorally and in different TAM sub-clusters. Functionally, we report that JHU083-reprogrammed TAMs have increased tumor cell phagocytosis and diminished pro-angiogenic capacities. In vivo inhibition of glutamine consumption in TAMs results in increased glycolysis, broken TCA cycle, and disruption in purine metabolism. Although the effect of glutamine antagonism was less profound on tumor-infiltrating T cells for their anti-tumor activity, it promoted a stem cell-like phenotype in CD8+ T cells and decreased the CD4+ Treg abundance. Additionally, we report that JHU083 causes a global shutdown in glutamine utilizing metabolic pathways in tumor cells, leading to reduced HIF-1, c-MYC phosphorylation, and induction of tumor cell apoptosis, all key anti-tumoral features.
Project description:Glutamine metabolism in the tumor microenvironment is emerging as a critical regulator of immune-mediated anti-tumor responses. We report potent tumor growth inhibition by the glutamine antagonist prodrug JHU083 in urologic tumors by JHU083-reprogrammed tumor-associated macrophages (TAMs) and tumor-infiltrating monocytes (TIMs). Using orthogonal approaches, we show that JHU083-mediated glutamine antagonism in the tumor microenvironment induces TNF, inflammatory, and mTORC1 signaling in different intra-tumoral TAM clusters. Additionally, we report that JHU083 increases proliferation in tissue-resident macrophages intratumorally and in different TAM sub-clusters. Functionally, we report that JHU083-reprogrammed TAMs have increased tumor cell phagocytosis and diminished pro-angiogenic capacities. In vivo inhibition of glutamine consumption in TAMs results in increased glycolysis, broken TCA cycle, and disruption in purine metabolism. Although the effect of glutamine antagonism was less profound on tumor-infiltrating T cells for their anti-tumor activity, it promoted a stem cell-like phenotype in CD8+ T cells and decreased the CD4+ Treg abundance. Additionally, we report that JHU083 causes a global shutdown in glutamine utilizing metabolic pathways in tumor cells, leading to reduced HIF-1, c-MYC phosphorylation, and induction of tumor cell apoptosis, all key anti-tumoral features.
Project description:It is now well-accepted that cancers co-opt the microenvironment to support their growth. However, the molecular mechanisms underlying cancer-microenvironment interactions remain poorly defined. We have found that Rho-associated kinase (ROCK) activity in the epithelial component of mammary tumors selectively actuates Protein kinase R-like endoplasmic reticulum kinase (Perk), causing the recruitment and persistent education of tumor-promoting cancer-associated fibroblasts (CAFs), a key component of the cancer microenvironment. Analysis of tumors from mice and human patients identified Cysteine-rich with EGF-like domains 2 (CRELD2), as the paracrine factor underlying PERK-mediated CAF-education downstream of ROCK. CRELD2 expression was found to be regulated by ATF4 downstream of the PERK pathway and knock-down of CRELD2 prevented tumor progression, demonstrating that the paracrine ROCK-PERK-ATF4-CRELD2 axis is a promoter of breast cancer progression and suggesting new therapeutic opportunities.
Project description:Acetate metabolism is an important metabolic pathway in many types of cancers and is primarily controlled by acetyl-CoA synthetase 2 (ACSS2), an enzyme that catalyzes the conversion of acetate to acetyl-CoA. However, the consequences of inhibiting tumor acetate metabolism on the tumor microenvironment and anti-tumor immunity are unknown. Herein we demonstrate that the growth of ACSS2 deficient triple negative breast cancer is severely impaired when host immunity is intact and, in many instances, ACSS2 deficient tumors are fully cleared by the immune system. Pharmacological inhibition of ACSS2 using a potent small molecule inhibitor reproduces these effects and enhances the efficacy of standard of care chemotherapy for TNBC. Single cell RNA sequencing of vehicle versus ACSS2 inhibitor treated tumors indicates differentiation and activation of T cells suggesting a crosstalk between acetate metabolism and immune cells in the tumor microenvironment. Our data suggest that blocking ACSS2 and acetate metabolism in tumors increases the availability of acetate in the tumor microenvironment. Tumor infiltrating T cells can then use acetate as a fuel source due to the relatively high expression of acetyl-CoA synthetase 1 (ACSS1), which is impervious to ACSS2 inhibitors. In this manner, ACSS1-driven oxidation of acetate in T cells helps to metabolically bolster anti-tumor immune responses. Based on our findings, we propose a completely novel paradigm for ACSS2 inhibitors as metaboimmunomodulators that dually act as inhibitors of tumor cell metabolism and modulators of tumor immunity.