Search

OBJECTIVE: Triple-negative breast cancers (TNBC) are a subtype of breast cancer lacking of estrogen receptor (ER), progesterone receptor (PR), and human EGF-like receptor 2 (HER2). MiR-193 always acted as an oncogene and promoted toxic aldehyde accumulation and tyrosine hydroxylase dysfunction. The purpose of this study is to explore the function of miR-193 in triple-negative breast cancer. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to examine the mRNA level of miR-193 expression in 50 cases of TNBC tissues and para-cancerous specimens. Also, the relation between miR-193 level and the overall survival of TNBC patient was analyzed. MiR-193 mimic and miR-193 inhibitor oligos, as well as the corresponding negative control, were synthesized from RiboBio (Guangzhou, China). RESULTS: MiR-193 expression was higher in triple-negative breast cancer tissues and cell lines than the corresponding adjacent non-tumor tissues and normal cell lines. Upregulation of miR-193 predicted poor prognosis of TNBC patients. Overexpression of miR-193 promoted cell proliferation and invasion, while that was suppressed by the knockdown of miR-193. MiR- 193 binds to the 3'-UTR of an inhibitor of growth family member 5 (ING5) mRNA to mediate the expression of ING5 in TNBC cells. The knockdown of miR-193 inhibited cell invasion-mediated epithelial- mesenchymal transition (EMT). Furthermore, the knockdown of miR-193 suppressed cell proliferation through the ING5/phosphatidylinositol 3-hydroxy kinase/protein kinase B (PI3K/AKT) signal pathway. CONCLUSIONS: MiR-193 enhanced cell invasion- mediated EMT and improved cell proliferation through the ING5/PI3K/AKT signal pathway in triple-negative breast cancer. The newly identified miR-193/ING5/PI3K/AKT axis provides novel insight into the pathogenesis of triple- negative breast cancer. [ABSTRACT FROM AUTHOR]

Summary: Inhibitor of growth 5, a tumor suppressor protein, can interact with p53, thereby inhibiting cell growth and inducing apoptosis. Inhibitor of growth 5 overexpression results in a reduction in colony-forming efficiency and cell population in S phase. To clarify the roles of inhibitor of growth 5 in tumorigenesis and progression of colorectal carcinomas, we examined inhibitor of growth 5 expression by immunohistochemistry on a tissue microarray containing colorectal carcinomas (n = 306), adenomas (n = 69), and nonneoplastic mucosa (n = 288) and compared this with clinicopathologic parameters of the carcinomas. In addition, inhibitor of growth 5 expression in colorectal carcinoma tissues and cell lines (DLD-1, HCT-15, SW480, and WiDr) was analyzed by Western blot and reverse transcriptase–polymerase chain reaction. It was found that the inhibitor of growth 5 protein was localized to the nuclei of colon carcinoma cells with no differences at mRNA levels. Among 18 frozen samples of colorectal carcinoma, significantly increased expression of inhibitor of growth 5 protein was observed in the carcinoma in comparison with adjacent mucosa in 14 cases (77.8%; P < .05), and 71.4% (10/14) of carcinoma cases exhibited up-regulated inhibitor of growth 5 mRNA expression. Decreased inhibitor of growth 5 expression was detected by immunohistochemistry in colorectal carcinoma, compared with non-neoplastic mucosa and adenoma (P < .05). Nuclear inhibitor of growth 5 expression was negatively correlated with tumor size, depth of invasion, degree of dedifferentiation, and Union Internationale Contre le Cancer staging (P < .05). In contrast, cytoplasmic inhibitor of growth 5 expression was positively correlated with depth of invasion, lymphatic invasion, and Union Internationale Contre le Cancer staging (P < .05). It was suggested that aberrant inhibitor of growth 5 expression may contribute to pathogenesis, growth, and invasion of colorectal carcinomas and could be considered as a promising marker to gauge aggressiveness of colorectal carcinomas. [Copyright &y& Elsevier]

Summary: ING5 can interact with p53, thereby inhibiting cell growth and inducing apoptosis. To clarify the roles of ING5 in gastric tumorigenesis and progression, its expression was examined by immunohistochemistry on a tissue microarray containing gastric nonneoplastic mucosa (n = 119), dysplasia (n = 50), and carcinomas (n = 429), with its comparison with clinicopathologic parameters of the carcinomas. ING5 expression was analyzed in gastric carcinoma tissues and cell lines (MKN28, MKN45, AGS, GT-3 TKB, and KATO-III) by Western blot and reverse transcriptase-polymerase chain reaction. ING5 protein was found to distribute to the nuclei of gastric carcinoma cells with similar messenger RNA levels. An increased expression of ING5 messenger RNA was observed in gastric carcinoma in comparison with paired mucosa (P < .05). Lower expression of nuclear ING5 was detected in gastric dysplasia and carcinoma than that in nonneoplastic mucosa (P < .05). Gastric nonneoplastic mucosa and metastatic carcinoma showed more expression of cytoplasmic ING5 than did gastric carcinoma and dysplasia (P < .05). Nuclear ING5 expression was negatively correlated with tumor size, depth of invasion, lymph node metastasis, and clinicopathologic staging (P < .05), whereas cytoplasmic ING5 was positively associated with depth of invasion, venous invasion, lymph node metastasis, and clinicopathologic staging (P < .05). Nuclear ING5 was more expressed in older than younger carcinoma patients (P < .05). There was a higher expression of nuclear ING5 in intestinal-type than diffuse-type carcinoma (P < .05), whereas it was the converse for cytoplasmic ING5 (P < .05). Survival analysis indicated that nuclear ING5 was closely linked to favorable prognosis of carcinoma patients (P < .05), albeit not independent. It was suggested that aberrant ING5 expression may contribute to pathogenesis, growth, and invasion of gastric carcinomas and could be considered as a promising marker to gauge aggressiveness and prognosis of gastric carcinoma. [Copyright &y& Elsevier]