SUMMARY Epithelial-mesenchymal transition (EMT) enhances invasiveness and confers tumor cells with cancer stem cell (CSC)-like characteristics. We showed that the Snail-G9a-Dnmt1 complex, which is critical for E-cadherin promoter silencing, is also required for the promoter methylation of fructose-1,6-biphosphatase (FBP1) in basal-like breast cancer (BLBC). Loss of FBP1 induces glycolysis and results in increased glucose uptake, macromolecules biosynthesis, formation of tetrameric PKM2, and maintenance of ATP production under hypoxia. Loss of FBP1 also inhibits oxygen consumption and ROS production by suppressing mitochondrial complex I activity; this metabolic reprogramming results in an increased CSC-like property and tumorigenicity by enhancing the interaction of β-catenin with TCF. Our study indicates that the loss of FBP1 is a critical oncogenic event in EMT and BLBC.

Summary Twist is a key transcription activator of epithelial-mesenchymal transition (EMT). It remains unclear how Twist induces gene expression. Here we reported a mechanism by which Twist recruits BRD4 to direct WNT5A expression in basal-like breast cancer (BLBC). Twist contains a “histone H4 mimic” GK-X-GK motif that is di-acetylated by Tip60. The di-acetylated Twist binds the second bromodomain of BRD4, whose first bromodomain interacts with acetylated H4, thereby constructs an activated Twist/BRD4/P-TEFb/RNA-PolII complex at the WNT5A promoter and enhancer. Pharmacologic inhibition of the Twist-BRD4 association reduced WNT5A expression and suppressed invasion, cancer stem cell (CSC)-like properties, and tumorigenicity of BLBC cells. Our study indicates that the interaction with BRD4 is critical for the oncogenic function of Twist in BLBC.

To identify genetic susceptibility loci for nasopharyngeal carcinoma (NPC), a genome-wide association study was performed using 464,328 autosomal SNPs in 1,583 NPC affected individuals (cases) and 1,894 controls of southern Chinese descent. The top 49 SNPs from the genome-wide association study were genotyped in 3,507 cases and 3,063 controls of southern Chinese descent from Guangdong and Guangxi. The seven supportive SNPs were further confirmed by transmission disequilibrium test analysis in 279 trios from Guangdong. We identified three new susceptibility loci, TNFRSF19 on 13q12 (rs9510787, Pcombined=1.53x10(-9), odds ratio (OR)=1.20), MDS1-EVI1 on 3q26 (rs6774494, Pcombined=1.34x10(-8), OR=0.84) and the CDKN2A-CDKN2B gene cluster on 9p21 (rs1412829, Pcombined=4.84x10(-7), OR=0.78). Furthermore, we confirmed the role of HLA by revealing independent associations at rs2860580 (Pcombined=4.88x10(-67), OR=0.58), rs2894207 (Pcombined=3.42x10(-33), OR=0.61) and rs28421666 (Pcombined=2.49x10(-18), OR=0.67). Our findings provide new insights into the pathogenesis of NPC by highlighting the involvement of pathways related to TNFRSF19 and MDS1-EVI1 in addition to HLA molecules.

No abstract