RESUMO
Background: Today, survivin is known as one of the most specific cancer proteins; provide unique and practical study opportunities. Clinical value of survivin in gastric cancer (GC) is not yet appointed. To establish the expression level of survivin and its diagnosis value in Iranian patients with GC, we evaluated the association of survivin expression with clinicopathologic factors. Methods: Overall, 60 matched-normal controls with 60 GC samples including 30 cases with evidence of metastasis at time of our study and 30 cases without evidence of metastasis were recruited, in Tehran, Iran during 2008 to 2018. Survivin expression was evaluated by quantitative Real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) study. Results: Increased expression of survivin at mRNA and protein levels was found in 86.7% and 71.6% of cases, respectively. Evidence indicated a significant difference in survivin mRNA expression level between tumor and nontumoral (marginal) tissues (P<0.001). The difference in expression of survivin mRNA was not significant between metastatic and non-metastatic tumor tissues (P=0.171). Positive immunoreactivity of survivin was observed to be predominantly in the nucleus of tumor cells. A significant difference in survivin protein expression was detected between tumor and non-tumoral tissues (P<0.001) and between metastatic and non-metastatic tumor tissues (P<0.001). There was no significant association between survivin mRNA expression and clinicopathological variables. However, survivin protein expression was significantly correlated with perineural involvement (P<0.018). Conclusion: This data could be supportive of using survivin as a useful diagnostic marker in GC. Although, more research is needed in this area.
RESUMO
Background: Microsatellite instability (MSI) is considered a key factor in carcinogenesis and a genetic alteration pattern in many types of cancers such as gastric cancer (GC). Although the role of MSI in colorectal cancer (CRC) is well known, its prognostic impact on GC has not been clearly defined. The assessment of MSI in GC has not been documented in the Iranian population yet. Therefore, this study analyzed the association of MSI status with GC in Iranian patients. Materials and Methods: We compared the frequency of MSI at 5 loci from formalin-fixed paraffin-embedded (FFPE) gastrectomy specimens, between metastatic and non-metastatic cases of GC (N = 60). A panel of five quasi-monomorphic markers and a single dinucleotide marker with linker-based fluorescent primers was used. Results: MSI was observed in 46.6% of cases, including MSI-high (H) (33.3%) and MSI-Low (L) (13.3%). Moreover, the most unstable and stable markers in our study were NR-21 and BAT-26 accordingly. MSI-H and MSI were seen more frequently in non-metastatic tumors (p= 0.028 and p= 0.019, respectively). Conclusion: The current study showed MSI status more frequently in non-metastatic GC which may reflect a good prognostic factor in GC like CRC. Although, larger and more comprehensive studies are needed to confirm this statement. A panel consisting of NR-21, BAT-25, and NR-27 mononucleotide markers appears to be reliable and useful markers for detecting MSI in GC in Iranian patients.
