Detection of transmembrane protein 100 in breast cancer: Correlation with malignant progression and chemosensitivity

With increased incidence, breast cancer has become the most common malignant tumor in women. Transmembrane protein 100 (TMEM100) is a key factor affecting the progression of malignant tumors. The aim of the study is to examine the molecular mechanism of TMEM100 in malignant progression.

TMEM100 expression was analyzed by Western blot, immunohistochemistry, and real-time quantitative polymerase chain reaction. Cell migration and invasiveness after transfection with TMEM100 were investigated by Transwell assay. 5-ethynyl-2-deoxyuridine staining and cell colony-formation assay were utilized to the exploration of cell proliferation. Flow cytometry was adopted to detect whether TMEM100 affected the effect of Docetaxel on cell apoptosis. The effects of TMEM100 on the Ras-extracellular signal-regulated kinase (RAS/ERK) pathway were explored by Western blot assay.

Downregulated TMEM100 expression was in breast cancer tissues (P < 0.01). TMEM100 overexpression hindered the invasion (P < 0.01), migration (P < 0.01), and proliferation (P < 0.01) of breast cancer cells. Chemotherapy sensitivity of breast cancer cells to docetaxel was enhanced by TMEM100 (P < 0.01). TMEM100 inhibited Ras expression and ERK1/2 phosphorylation (P < 0.01). Furthermore, ERK agonist TertButylhydroquinone neutralized the effects of TMEM100 (P < 0.01).

TMEM100 blocked malignant progression of breast cancer and enhanced docetaxel chemosensitivity by suppressing RAS/ERK pathway. These data manifested that regulation of TMEM100 expression may affect the progression of breast cancer, and its prognostic value and mechanism deserve further investigation.