Long noncoding RNA FAM66C promotes tumor progression and glycolysis in intrahepatic cholangiocarcinoma by regulating hsa-miR-23b-3p/KCND2 axis.

Long noncoding RNAs (lncRNAs) are known to be the important regulators in cancer progression. However, the role of lncRNA FAM66C (FAM66C) is yet to be investigated in intrahepatic cholangiocarcinoma (ICC). This study aimed to investigate the effects and related mechanisms of FAM66C in ICC. Human ICC tissues and cell lines were collected. The expression levels of FAM66C, hsa-miR-23b-3p (miR-23b-3p), and KCND2 were detected by qRT-RCR. The transfection experiments were employed to measure the effect of FAM66C on cell viabilities, migration, and invasion in ICC cells by CCK-8, transwell assays. Glycolysis was investigated by glucose consumption, lactate production and ATP levels. The dual-luciferase reporter and RNA pull down assays were conducted as a means of confirming the interactions between FAM66C, miR-23b-3p, and KCND2. Furthermore, the levels of the EMT-associated proteins (KCND2, GLUT1, PKM2, and LDHA) in ICC cells were detected by western blot. FAM66C was increased in ICC tissues and cells, increased cell viability, glycolysis, migration and invasion, and decreased apoptosis were shown in FAM66C overexpressing cells. Mechanistic analyses revealed that FAM66C regulated the downstream target gene KCND2 by sponging miR-23b-3p. FAM66C effect on ICC was further validated in murine xenograft assays. FAM66C knockdown cells gave rise to tumors that were smaller in size, consistent with the role of FAM66C as a promoter of in vivo tumor growth. These data revealed that FAM66C was able to drive ICC tumor progression and glycolytic activity via the miR-23b-3p/KCND2 axis, indicating FAM66C may be a viable target for treating ICC.

Upregulation of long noncoding RNA W42 promotes tumor development by binding with DBN1 in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a malignancy found globally. Accumulating studies have shown that long noncoding RNAs (lncRNAs) play critical roles in HCC. However, the function of lncRNA in HCC remains poorly understood. AIM: To understand the effect of lncRNA W42 on HCC and dissect the underlying molecular mechanisms. METHODS: We measured the expression of lncRNA W42 in HCC tissues and cells (Huh7 and SMMC-7721) by quantitative reverse transcriptase polymerase chain reaction. Receiver operating characteristic curves were used to assess the sensitivity and specificity of lncRNA W42 expression. HCC cells were transfected with pcDNA3.1-lncRNA W42 or shRNA-lncRNA W42. Cell functions were detected by cell counting Kit-8 (CCK-8), colony formation, flow cytometry and Transwell assays. The interaction of lncRNA W42 and DBN1 was confirmed by RNA immunoprecipitation and RNA pull down assays. An HCC xenograft model was used to assess the role of lncRNA W42 on tumor growth in vivo. The Kaplan-Meier curve was used to evaluate the overall survival and recurrence-free survival after surgery in patients with HCC. RESULTS: In this study, we identified a novel lncRNA (lncRNA W42), and investigated its biological functions and clinical significance in HCC. LncRNA W42 expression was upregulated in HCC tissues and cells. Overexpression of lncRNA W42 notably promoted the proliferative and invasion of HCC, and inhibited cell apoptosis. LncRNA W42 directly bound to DBN1 and activated the downstream pathway. LncRNA W42 knockdown suppressed HCC xenograft tumor growth in vivo. The clinical investigation revealed that HCC patients with high lncRNA W42 expression exhibited shorter survival times. CONCLUSION: In vitro and in vivo results suggested that the novel lncRNA W42, which is upregulated in HCC, may serve as a potential candidate prognostic biomarker and therapeutic target in HCC patients.