High expression of disabled homolog 2-interacting protein contributes to tumor development and proliferation in cutaneous squamous cell carcinoma

BACKGROUND: Disabled homolog 2-interacting protein (DAB2IP), a Ras GTPase-activating protein, is downregulated in several cancers. Its depletion is involved in tumor cell proliferation, apoptosis, and metastasis, as well as epithelial–mesenchymal transition. The present study aimed to explore the potential role of DAB2IP in cutaneous squamous cell carcinoma (cSCC) and provide a theoretical basis for the diagnosis and targeted therapy of cSCC. METHODS: The clinicopathological features of DAB2IP expression in cSCC were analyzed by immunohistochemistry, and the effects of DAB2IP on SCL-1 cell behavior were determined via genetic interference in vitro. SCL-1 cell lines that exhibited reduced expression of DAB2IP and a scrambled shRNA control were constructed using a lentivirus vector-based shRNA technique. RNA extraction, reverse transcription-quantitative PCR (RT-qPCR), MTT assay, colony formation test, cell cycle analysis, apoptosis test, transwell assay, wound-healing assay, in vitro invasive assay were used in this study. RESULTS: The immunohistochemical results demonstrated that the expression of DAB2IP was higher in cSCC tissues than in soft fibroma. The level of DAB2IP expression was associated with the degree of malignancy and the depth of tumor infiltration; however, it had no association with patients’ sex, tumor size, location, or phenotype. The results of the MTT, cell cycle, apoptosis, and invasion experiments demonstrated that knockdown of DAB2IP inhibited the viability and invasion of SCL-1 cells in vitro. CONCLUSIONS: High expression of DAB2IP may contribute to the development and proliferation of cSCC.