23:T4e5,c-Myc is frequently overexpressed in tumors and plays an important role in the regulation of cancer metabolism. Hypoxia-inducible factor-1 (HIF1), the master regulator of the hypoxic response, enhances tumorigenesis and influences metabolism via upregulation of the glycolytic pathway and suppression of mitochondrial respiration. Together, deregulated Myc and HIF1 cooperate to lend metabolic advantages to proliferating cancer cells and contribute to the Warburg effect. Here we show that overexpression of Myc significantly stabilizes the α subunit of HIF1 (HIF1α) under normoxic conditions and enhances HIF1α accumulation under hypoxic conditions in cells. Posttranscriptional regulation of HIF1α by Myc led to the induction of HIF1α gene targets. Normoxic HIF1α protein expression was also dependent on Myc. Functionally, HIF1α expression was required for Myc-induced anchorage-independent growth and cell proliferation. Myc-dependent stabilization of HIF1α involved either disruption of binding to the VHL complex or posttranslational protein modifications. Taken together, our findings uncover a previously uncharacterized regulatory relationship between Myc and HIF1 that has important implications for cancer metabolism and development.24:T550,N6-methyladenosine (m⁶A) is the richest modification in mammalian messenger RNAs (mRNAs), and exerts key roles in many biological processes, including cancer development, whereas its roles in prostate carcinoma (PCa) remain to be unclear. Here, we found that m⁶A modifications are increased in PCa and methyltransferase-like 3 (METTL3), but not other major m⁶A modification genes including METTL14, fat mass and obesity-associated protein (FTO) and AlkB homolog 5 (ALKBH5), was the major dysregulated gene associated with abnormal m⁶A modification. In addition, METTL3 up-regulation acted as a poor prognostic factor for overall survival and disease-free survival in PCa patients. Knockdown of METTL3 significantly inhibited PCa cells proliferation, migration, and invasion. In addition, over-expression of METTL3, but not its catalytic mutant form, significantly promoted PCa cells growth and progression. Mechanistically, we revealed that METTL3 enhanced MYC(c-myc) expression by increasing m⁶A levels of MYC mRNA transcript, leading to oncogenic functions in PCa. Importantly, PCa cells growth and progression inhibition by METTL3 knockdown were restored through over-expression of MYC. Our results uncovered a METTL3/m⁶A/MYC axis and provided insight into the mechanisms of PCa progression.25:T57f,

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