Article Type: Original Article
Abstract: Introduction: Gastric cancer is the fourth most common cancer worldwide, with a frequency that varies greatly across different geographic locations. In Iran, gastric cancer is the second most common cancer in men but it is the first most lethal neoplasm overall. MSI2 functions as an RNA-binding protein and plays a central role in post-transcriptional gene regulation. Some studies revealed cell type-specific and developmentally regulated expression of MSI2 in the mammalian CNS. Recently,it has been showed thatMSI2 expression is not only highly up-regulated during human CML progression but is also an early indicator of poorer prognosis. To investigate potential involvement ofMSI2 in gastric cancer, we examined, for the first time, its expression in human normal and tumoral gastric specimens. Method: 30 (paired) fresh frozen normal and tumoral gastric specimens were provided from Iran Tumor Bank. Specific primers for MSI2 and TBP (as an internal control) were designed and used for measuring relative expression of MSI2 by quantitative real-time RT-PCR. Results:According to the relative expression level of theMSI2 gene, the samples can be categorized into 3 classes. The first class included those samples in which MSI2 over-expressed in tumoral tissues compared to their normal adjacent specimen (n=8). In the second class, there were no significant changes in the expression level of the gene between the tumoral and normal paired tissues (n=3). Finally those samples in which MSI2 under-expressed in tumoral tissues placed in the third class (n=4). By pooling all the data, there was no significant difference in the MSI2 gene expression between tumoral and normal tissues. Conclusion: Our results indicated that MSI2 is heterogeneously expressed in gastric cancer and has a potential to be used as a marker for classifying the tumors.