Departments of, Department of, Dermatology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
Department of, Pathology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
Clin Exp Dermatol. 2020 Dec;45(8):1027-1034. doi: 10.1111/ced.14322. Epub 2020 Aug 4.
Basal cell carcinoma (BCC) is the most common form of skin carcinoma.
To investigate the function of key micro(mi)RNAs and to explore the potential molecular mechanisms involved in BCC.
The microarray dataset GSE34535, which comprises seven BCC samples and seven control samples, was downloaded from the Gene Expression Omnibus database. Differentially expressed miRNAs (DE-miRNAs) were identified. We collected tissue samples from 20 patients with BCC and 20 healthy controls (HCs), to compare the miR-18a expression in their tissue samples. Expression of miR-18a in A431 and HaCaT cells was also assayed. Following this, we upregulated and downregulated miR-18a expression in A431 cells to examine the effects on cell proliferation, migration and apoptosis. To further investigate the relative mechanism, the proteins LC3, Beclin 1, Akt and mammalian target of rapamycin (mTOR) were examined by quantitative real-time PCR and Western blotting. For further verification, we examined the expression of LC3 in the 20 BCC and 20 HC tissue samples.
In total, 19 DE-miRNAs (13 upregulated and 6 downregulated) that were common to the BCC and HC groups were identified. Levels of miR-18a were about three-fold higher in BCC tissues and A431 cells compared with their respective control groups. In vitro, downregulation of miR-18a was shown to inhibit cell proliferation and activate autophagy via the Akt/mTOR signalling pathway, while upregulation of miR-18a promoted proliferation of these cells. LC3 was decreased in BCC compared with HC tissue samples.
Our data support an oncogenic role of miR-18a through a novel Akt/mTOR/Beclin 1/LC3 axis, and suggest that the antitumour effects of miR-18a inhibitor may make it suitable for BCC therapy.
基底细胞癌（BCC）是最常见的皮肤癌。
研究关键微小 RNA（miRNA）的功能，并探讨其在 BCC 中涉及的潜在分子机制。
从基因表达综合数据库下载包含 7 个 BCC 样本和 7 个对照样本的 microarray 数据集 GSE34535，以确定差异表达的 miRNA（DE-miRNA）。我们收集了 20 例 BCC 患者和 20 例健康对照（HC）的组织样本，比较其组织样本中 miR-18a 的表达。还检测了 miR-18a 在 A431 和 HaCaT 细胞中的表达。在此基础上，我们上调和下调 A431 细胞中的 miR-18a 表达，以观察对细胞增殖、迁移和凋亡的影响。为了进一步探讨相关机制，通过定量实时 PCR 和 Western blot 检测 LC3、Beclin 1、Akt 和哺乳动物雷帕霉素靶蛋白（mTOR）的蛋白表达。为了进一步验证，我们检测了 20 例 BCC 和 20 例 HC 组织样本中 LC3 的表达。
总共鉴定出 19 个在 BCC 和 HC 组中均上调或下调的 DE-miRNA（上调 13 个，下调 6 个）。BCC 组织和 A431 细胞中的 miR-18a 水平比相应的对照组高约 3 倍。在体外，下调 miR-18a 通过 Akt/mTOR 信号通路抑制细胞增殖并激活自噬，而上调 miR-18a 则促进这些细胞的增殖。与 HC 组织样本相比，LC3 在 BCC 中减少。
我们的数据支持 miR-18a 通过一种新的 Akt/mTOR/Beclin 1/LC3 轴发挥致癌作用，并表明 miR-18a 抑制剂的抗肿瘤作用可能使其适合 BCC 治疗。
