• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2813-2818
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• 2012

Background: Considerable evidence suggests that metadherin (MTDH) is a potentially crucial mediator of tumor malignancy and an important therapeutic target for simultaneously enhancing chemotherapy efficacy and reducing metastasis risk. Inhibition of MTDH expression by RNA interference has been shown in several previous research, but silencing MTDH expression by microRNA (miRNA) interference in breast cancer has not been established. In the present study, we investigated the role of MTDH-miRNA in down-regulation of proliferation, motility and migration of breast carcinoma cells. Methods: Expression vectors of recombinant plasmids expressing artificial MTDH miRNA were constructed and transfected to knockdown MTDH expression in MDA-MB-231 breast cancer cells. Expression of MTDH mRNA and protein was detected by RT-PCR and Western blot, respectively. MTT assays were conducted to determine proliferation, and wound healing assays and transwell migration experiments for cell motility and migration. Results: Transfection of recombinant a plasmid of pcDNA-MTDH-miR-4 significantly suppressed the MTDH mRNA and protein levels more than 69% in MDA-MB-231 breast cancer cells. This knockdown significantly inhibited proliferation, motility and migration as compared with controls. Conclusions: MTDH-miRNA may play an important role in down-regulating proliferation, motility and migration in breast cancer cells, and should be considered as a potential small molecule inhibitor therapeutic targeting strategy for the future.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2833-2836
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• 2012

Aim: Gastric cancer is the third most frequent cause of cancer mortality worldwide. In Iran, it is one of the leading causes at the national level. Localized at chromosome 8q22, the human MTDH gene has been reported to be over-expressed in a spectrum of malignancies. However, since there is a lack of data concerning with expression in gastric cancer at the transcriptional level, in this study we evaluated MTDH expression in Iranian cases. Methods: Totally, thirty paired gastric samples were examined by quantitative real-time RT-PCR. Results: Although the mRNA expression was significantly elevated in 46.6% of the examined tumor tissues; its expression was low in others (36.6%). Moreover, there was only a marginal statistical difference between the MTDH gene expression of all tumor specimens compared to their paired non-tumor ones and no statistically significant association with the grades and types of the tumors. Conclusion: Taken together, our results demonstrated that expression of MTDH at the transcriptional level may be increased in gastric cancer tissue samples but with considerable heterogeneity. Due to this, it may have the potential to be used as a target for diagnostic/therapeutic purposes only in a subset of patients.