MicroRNA-33b inhibits cell proliferation and glycolysis by targeting hypoxia-inducible factor-1α in malignant melanoma

Abstract

Malignant melanoma (MM) is the most aggressive type of skin cancer. MicroRNA (miR) has been implicated in the development and progression of MM; however, their underlying mechanism of action remains largely unknown. The present study aimed to investigate the role of miR-33b in MM. Reverse transcription-quantitative polymerase chain reaction data indicated that the expression of miR-33b was significantly reduced (P<0.01) in MM cell lines, including WM35, WM451 and SK-MEL-1, when compared with human melanocyte cells. Subsequently, WM451 and SK-MEL-1 cells were transfected with an miR-33b mimic or inhibitor. MTT assay data demonstrated that the viability of MM cells markedly decreased following miR-33b overexpression; however, viability was markedly upregulated following miR-33b knockdown. Additionally, the glycolysis level was examined. Results demonstrated that glucose consumption and lactic acid production were significantly downregulated (P<0.01) after miR-33b upregulation, whereas these levels significantly increased in MM cells transfected with miR-33b inhibitor (P<0.01), suggesting that miR-33b negatively mediates the glycolysis level in MM cells. Bioinformatics indicated that hypoxia-inducible factor (HIF)-1α was a putative target gene of miR-33b, and this was confirmed by a luciferase reporter assay, which demonstrated that miR-33b was able to directly bind to the 3′ untranslated region of HIF-1α mRNA. Furthermore, the expression of HIF-1α was negatively regulated by miR-33b at the post-transcriptional level in MM cells. Overexpression of HIF-1α reversed the inhibitory effect of miR-33b on the proliferation and glycolysis in MM cells. Finally, the results of the present study demonstrated that hexokinase 2 and lactate dehydrogenase-A may be involved in miR-33b/HIF-1α mediated glycolysis in MM cells. In conclusion, these results suggest that miR-33b inhibits cell proliferation and glycolysis by targeting HIF-1α in MM.

Downregulation of miR‐33b promotes non‐small cell lung cancer cell growth through reprogramming glucose metabolism miR‐33b regulates non‐small cell lung cancer cell growth

“…26,27 Further, we showed that miR-33b overexpression attenuated the proliferation, colony formation of NSCLC cells and promoted cell cycle arrest and apoptosis ( Figure 2). Currently, surgery is the primary treatment modality for NSCLC patients in stage I, II &III.…”

“…LDHA is an enzyme of the glycolytic pathway, which plays a role in the regulation of glycolysis in anaerobic conditions. 26 Notably, miR-33b also regulates the metabolism of fatty acids, 35 and other cancer-related processes, such as angiogenesis, hypoxia, etc., which presumably all contribute to the tumor-attenuation effects of miR-33b. 32 In our study, the interaction between LDHA and miR-33b was verified by luciferase reporter assay.…”

“…LDHA has been used as a biomarker in various cancers. 26,27 Besides, as a broad-spectrum regulatory molecules, miR-33b has also been shown to regulate genes, such as NPC1 (Niemann Pick C), ABCA1 (ATP-Binding Casette A1), ABCG1 (ATP-Binding Casette G1), CPT1A (carnitine palmitoyltransferase 1A), CROT (carnitine O-octanoyltransferase), and HADHB (hydroxyacyl-CoA dehydrogenase/3-ketoacy-CoA thiolase/enoyl-CoA hydratase β subunit). Moreover, overexpression of LDHA was shown to antagonize the tumor-suppressing effects of miR-33b.…”

“…Here we show that miR-33b is downregulated in NSCLC tissue and cells, which is in line with previous reports that miR-33b serves as a tumor suppressor. 26,27 Further, we showed that miR-33b overexpression attenuated the proliferation, colony formation of NSCLC cells and promoted cell cycle arrest and apoptosis (Figure 2). These data implicated the use of miR-33b for NSCLC therapy.…”

Oxaloacetate induces apoptosis in HepG2 cells via inhibition of glycolysis

“…Although changes in metabolites can regulate cellular metabolism, genes, and related signaling pathways also affect metabolic processes in cancer cells [25,26]. The Akt/HIF signaling pathway regulates aerobic glycolysis through transcriptional activation of HIF1α, NFκB, c-myc, and the subsequent expression of glycolytic enzymes such as hexokinase 2 (HK2), phosphofructokinase 2 (PFK2), and pyruvate kinase isozyme type M2 (PKM2) [27][28][29][30][31]. In our research, we found OA inhibited the expression of glycolytic enzymes through inhibition of the Akt/HIF signaling pathway.…”