1. miR-181a decelerates proliferation in cutaneous squamous cell carcinoma by targeting the proto-oncogene KRAS.
- Author
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Neu J, Dziunycz PJ, Dzung A, Lefort K, Falke M, Denzler R, Freiberger SN, Iotzova-Weiss G, Kuzmanov A, Levesque MP, Dotto GP, and Hofbauer GFL
- Subjects
- Animals, Apoptosis, Carcinoma, Squamous Cell genetics, Carcinoma, Squamous Cell metabolism, Cell Differentiation, Cell Movement, Female, Humans, Mice, Mice, Nude, Proto-Oncogene Mas, Proto-Oncogene Proteins p21(ras) genetics, Signal Transduction, Skin metabolism, Skin Neoplasms genetics, Skin Neoplasms metabolism, Carcinoma, Squamous Cell pathology, Cell Proliferation, Gene Expression Regulation, Neoplastic, MicroRNAs genetics, Proto-Oncogene Proteins p21(ras) metabolism, Skin pathology, Skin Neoplasms pathology
- Abstract
Cutaneous squamous cell carcinoma (SCC) is the second most common human skin cancer with a rapidly increasing incidence among the Caucasian population. Among the many regulators, responsible for cancer progression and growth, microRNAs (miRNA) are generally accepted as key players by now. In our current study we found that microRNA-181a (miR-181a) shows low abundance in SCC compared to normal epidermal skin. In vitro, miRNA downregulation in normal primary keratinocytes induced increased proliferation, while in vivo miR-181a downregulation in HaCaT normal keratinocytes showed tumor-like growth increase up to 50%. Inversely, upregulation of these miRNAs in cancer cells lead to reduced cellular proliferation and induction of apoptosis in vitro. An in vivo therapeutic model with induced miR-181a expression in SCC13 cancer cells reduced tumor formation in mice by 80%. Modulation of miR-181a levels showed an inverse correlation with the proto-oncogene KRAS both on mRNA and protein level by direct interaction. Knockdown of KRAS mimicked the anti-proliferative effects of miR-181a overexpression in patient-derived SCC cells and abolished the enhanced viability of HaCaT cells following miR-181a knockdown. Furthermore, phospho-ERK levels correlated with KRAS levels, suggesting that the observed effects were mediated via the MAPK signaling pathway. miR-181a seemed regulated during keratinocyte differentiation probably in order to amplify the tumor suppressive character of differentiation. Taken together, miR-181a plays a crucial tumor suppressive role in SCC by targeting KRAS and could be a promising candidate for a miRNA based therapy.
- Published
- 2017
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