Lipid droplet tethering with mitochondria for fatty acid oxidation is critical for tumor cells to counteract energy stress. However, the underlying mechanism remains unclear. Here, we demonstrate that glucose deprivation induces phosphorylation of the glycolytic enzyme phosphofructokinase, liver type (PFKL), reducing its activity and favoring its interaction with perilipin 2 (PLIN2).
View Article and Find Full Text PDFTelomere dysfunction is intricately linked to the aging process and stands out as a prominent cancer hallmark. Here we demonstrate that telomerase activity is differentially regulated in cancer and normal cells depending on the expression status of fructose-1,6-bisphosphatase 1 (FBP1). In FBP1-expressing cells, FBP1 directly interacts with and dephosphorylates telomerase reverse transcriptase (TERT) at Ser227.
View Article and Find Full Text PDFBackground And Aims: Cross talk between tumor cells and immune cells enables tumor cells to escape immune surveillance and dictate responses to immunotherapy. Previous studies have identified that downregulation of the glycolytic enzyme fructose-1,6-bisphosphate aldolase B (ALDOB) in tumor cells orchestrated metabolic programming to favor HCC. However, it remains elusive whether and how ALDOB expression in tumor cells affects the tumor microenvironment in HCC.
View Article and Find Full Text PDFHigh expression of PD-L1 in tumor cells contributes to tumor immune evasion. However, whether PD-L1 expression in tumor cells is regulated by the availability of nutrients is unknown. Here, we show that in human glioblastoma cells, high glucose promotes hexokinase (HK) 2 dissociation from mitochondria and its subsequent binding and phosphorylation of IκBα at T291.
View Article and Find Full Text PDFBackground And Aims: Insulin receptor (IR) transduces cell surface signal through phosphoinositide 3-kinase (PI3K)-AKT pathways or translocates to the nucleus and binds to the promoters to regulate genes associated with insulin actions, including de novo lipogenesis (DNL). Chronic activation of IR signaling drives malignant transformation, but the underlying mechanisms remain poorly defined. Down-regulation of fructose-1,6-bisphosphate aldolase (ALDO) B in hepatocellular carcinoma (HCC) is correlated with poor prognosis.
View Article and Find Full Text PDFLoss of hepatic fructose-1, 6-bisphosphate aldolase B (Aldob) leads to a paradoxical up-regulation of glucose metabolism to favor hepatocellular carcinogenesis (HCC), but the upstream signaling events remain poorly defined. Akt is highly activated in HCC, and targeting Akt is being explored as a potential therapy for HCC. Herein, we demonstrate that Aldob suppresses Akt activity and tumor growth through a protein complex containing Aldob, Akt, and protein phosphatase 2A (PP2A), leading to inhibition of cell viability, cell cycle progression, glucose uptake, and metabolism.
View Article and Find Full Text PDFHepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. Here, we identified that increased miR-23a expression in HCC tissues was associated with worse survival. More importantly, we found that STAT5A was a target of miR-23a, whose levels significantly decreased in tumor tissues.
View Article and Find Full Text PDFThe well-documented anticarcinogenic properties of natural polyphenolic proanthocyanidins (OPC) have been primarily attributed to their antioxidant and anti-inflammatory potency. Emerging evidence suggests that OPC may target canonical oncogenic pathways, including PI3K/AKT; however, the underlying mechanism and therapeutic potential remain elusive. Here we identify that proanthocyanidin B2 (OPC-B2) directly binds and inhibits AKT activity and downstream signalling, thereby suppressing tumour cell proliferation and metabolism in vitro and in a xenograft and diethyl-nitrosamine (DEN)-induced hepatocellular carcinoma (HCC) mouse models.
View Article and Find Full Text PDFAutophagy is an evolutionarily conserved catabolic process that recycles proteins and organelles in a lysosome-dependent manner and is induced as an alternative source of energy and metabolites in response to diverse stresses. Inhibition of autophagy has emerged as an appealing therapeutic strategy in cancer. However, it remains to be explored whether autophagy inhibition is a viable approach for the treatment of hepatocellular carcinoma (HCC).
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