5‑Aza‑dC suppresses melanoma progression by inhibiting GAS5 hypermethylation

Oncol Rep. 2022 Jul;48(1):123. doi: 10.3892/or.2022.8334. Epub 2022 May 20.

Abstract

The in‑depth study of melanoma pathogenesis has revealed that epigenetic modifications, particularly DNA methylation, is a universal inherent feature of the development and progression of melanoma. In the present study, the analysis of the tumor suppressor gene growth arrest‑specific transcript 5 (GAS5) demonstrated that its expression was downregulated in melanoma, and its expression level had a certain negative association with its methylation modification level. The promoter of GAS5 presented with detectable CpG islands, and methylation‑specific polymerase chain reaction analysis demonstrated that GAS5 was actually modified by methylation in melanoma tissues and cells; however, no methylation modification of GAS5 was detected in normal tissues. Following the treatment of melanoma cells with 5‑Aza‑2'‑deoxycytidine (5‑Aza‑dC), GAS5 methylation was significantly reversed. The analysis of melanoma cell proliferation revealed that 5‑Aza‑dC inhibited A375 and SK‑MEL‑110 cell proliferation in a time‑dependent manner. Further analysis of apoptosis demonstrated that 5‑Aza‑dC significantly increased the apoptosis level of the two cell lines. Moreover, migration analysis of melanoma cells revealed that 5‑Aza‑dC significantly reduced cell migration. Furthermore, 5‑Aza‑dC significantly decreased the invasive ability of the two cell lines. However, when the expression of GAS5 was silenced, the effects of 5‑Aza‑dC on cell proliferation, apoptosis, invasion and migration were not significant. Furthermore, the subcutaneous injection of A375 cells in nude mice successfully resulted in xenograft tumor formation. However, following an intraperitoneal injection of 5‑Aza‑dC, the volume and weight of xenograft tumors and Ki‑67 expression were significantly reduced, and caspase‑3 activity and GAS5 expression were enhanced; following the silencing of GAS5, the antitumor effect of 5‑Aza‑dC was significantly blocked. On the whole, the present study demonstrates that 5‑Aza‑dC inhibits the growth of melanoma, and its function may be related to the methylation modification of GAS5.

Keywords: 5‑Aza‑2'‑deoxycytidine; growth arrest‑specific transcript 5; lncRNA; melanoma; methylation.

MeSH terms

  • Animals
  • Apoptosis
  • Azacitidine / pharmacology
  • Cell Line, Tumor
  • Cell Proliferation
  • DNA Methylation
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Melanoma* / genetics
  • Mice
  • Mice, Nude
  • RNA, Long Noncoding* / genetics

Substances

  • RNA, Long Noncoding
  • Azacitidine

Grants and funding

The present study was supported by the National Natural Science Foundation of China (grant no. 81960496), the China Postdoctoral Science Foundation (grant no. 2019M653501), the Yunnan Fundamental Research Projects (grant nos. 202101AT070050, 202001AY070001-247 and 202101AY070001-157), the Scientific Research Fund of Yunnan Education Department (grant no. 2019J1286), XingDianYingCai support plan, and the Reserve talents of Medical Science of Yunnan Province (H-2018055).