siRNA沉默USP22基因对胃癌细胞增殖的抑制作用

Expression of USP22, MTA1 and Ki-67 in esophageal squamous cell carcinoma

AIM: To investigate the expression of ubiquitin specific peptidase 22 (USP22), metastasis associated gene 1 (MTA1) and nuclear associated antigen (Ki-67) in esophageal squamous cell carcinoma (ESCC) and to analyze their relationship with clinicopathologic features of ESCC.

METHODS: Immunohistochemistry was used to detect the expression of USP22, MTA1 and Ki-67 proteins in ESCC, matched tumor-adjacent tissue and normal esophageal tissue. The correlation between the expression of these proteins and clinicopathologic features of ESCC was analyzed.

RESULTS: The positive rate of USP22 expression in ESCC was significantly higher than that in tumor-adjacent tissue and normal esophageal tissue (68.18% vs 36.36%, 15.91%, both P < 0.05). Expression of USP22 was significantly associated with tumor invasion depth and histological grade, but not with age, sex or lymph node metastasis. The positive rate of MTA1 expression was also significantly higher in ESCC than in tumor-adjacent tissue and normal esophageal tissue (61.36% vs 31.82%, 6.82%, both P < 0.05). MTA1 expression was significantly associated with lymph node metastasis, tumor invasion depth and histological grade, but not with age or sex. The positive rate of Ki-67 expression was also significantly higher in ESCC than in tumor-adjacent tissue and normal esophageal tissue (70.45% vs 43.18%, 11.36%, both P < 0.05). Expression of Ki-67 was significantly associated with lymph node metastasis, tumor invasion depth and histological grade, but not with age or sex. USP22 protein expression was positively correlated with the expression of MTA1 and Ki-67 proteins; however, the expression of MTA1 protein was not significantly correlated with that of Ki-67 protein.

CONCLUSION: USP22, MTA1 and Ki-67 may participate in the occurrence and metastasis of esophageal carcinoma. Combined detection of the expression of these proteins will be helpful to the diagnosis of esophageal carcinoma and accurate determination of the biological behavior of this malignancy. USP22, MTA1 and Ki-67 may become new targets for gene therapy of esophageal carcinoma.

Transfection of miRNAs targeting the FUT3 gene inhibits cell proliferation in human gastric cancer cell line KATO-III

AIM: To investigate the effect of inhibition of FUT3 gene expression with miRNAs on the proliferation of gastric cancer cells (KATO-Ⅲ).

METHODS: Vectors carrying two miRNAs targeting the FUT3 gene were constructed and transiently transfected into KATO-III cells using lipidosome-mediated method. RT-PCR was performed to detect the expression of FUT3 mRNA, and immunocytochemistry and flow cytometry analysis were carried out to test expression variation of sLeA antigen. MTT assay and colony-forming assay were used to analyze cell proliferation and to detect the effect of decreased FUT3 expression on cell growth.

RESULTS: Compared to non-transfected cells and cells transfected with empty vector, the relative expression levels of FUT3 mRNA were significantly decreased (0.41 ± 0.01 vs 0.71 ± 0.05, 0.65 ± 0.03, both P < 0.05; 0.36 ± 0.02 vs 0.71 ± 0.05, 0.65 ± 0.03, both P < 0.05); the sLeA antigen expression levels were also significantly reduced (35.51% ± 0.36% vs 52.79% ± 2.62%, 49.75% ± 1.29%, both P < 0.05; 26.05% ± 1.14% vs 52.79% ± 2.62%, 49.75% ± 1.29%, both P < 0.05); cell growth was significantly inhibited (38.10% ± 1.96% vs 5.6% ± 0.63%, 8.9% ± 0.91%, both P < 0.05; 49.04% ± 2.37% vs 5.6% ± 0.63%, 8.9% ± 0.91%, both P < 0.05); and colony-forming ability was significantly reduced (14.10% ± 1.70% vs 29.79% ± 3.05%, 28.92% ± 2.10%, both P < 0.05; 12.50% ± 1.96% vs 29.79% ± 3.05%, 28.92% ± 2.10%, both P < 0.05) in FUT3-miRNA and FUT3-miRNA2 transfeced cells.

CONCLUSION: Transfection of miRNAs targeting the FUT3 gene can effectively inhibit the proliferation of KATO-Ⅲ cells.