The Expression Of FAM96A,FAM96B And Caspase 3 In Gastrointestinal Stromal Tumor And Its Correlation With Clinicopathologic Characteristics

Objective:To investigate the expression of family with sequence similarity 96,member A(FAM96A),family with sequence similarity96,member B(FAM96B)and cysteinyl aspartate specific proteinase 3(caspase3)in gastrointestinal stromal tumor(GIST)and its corresponding normal tissue,and to explore its correlation with clinicopathologic characteristics.Methods:The immunohistochemical En Vision method was used to detect the expression and distribution of FAM96A,FAM96B and caspase 3 in GIST and its normal tissue;the expression of FAM96A m RNA and FAM96B m RNA in GIST and normal tissue from 30 patients was detected by SYBR Green real-time reverse transcriptase polymerase chain reaction(real-time RT-PCR).Results:In 120cases of GIST and their normal tissue,FAM96A protein of 110 cases were found to be positive in normal tissue,accounting for 91.67%(110/120),and 17cases were found in the GIST,accounting for 14.17%(17/120);107 cases positively expressed FAM96B protein in normal tissue,the positive expression rate was 89.17%(107/120),and 26 cases were found in the GIST,the rate was21.67%(26/120);the positive expression of caspase 3 in normal tissue and GIST had a significant difference,the positive expression rate was 90.00%(108/120)and 65.00%(78/120),respectively.The protein expression of FAM96A,FAM96B and caspase 3 significantly decreased in comparison with their normal tissue(P<0.05);In addition,the expression of FAM96A and FAM96B was both associated with tumor size and risk-groups(?~2=4.55 P=0.03,?~2=4.67 P=0.03,?~2=8.68 P=0.01,?~2=8.58 P=0.00),the positive rate in GIST group less than 5cm in size was higher than that in group with more than 5cm in size;the positive rate was higher in the very low and low risk-groups than in the medium and high risk-groups.But had no correlation with sex,age,location and mitotic figures(P>0.05);the expression of caspase 3 protein in different sex,age,tumor location,size,mitotic figures and risk-groups was not different statistically(P>0.05).The Spearman rank correlation analysis showed that protein expression in GIST in those with positive FAM96A and FAM96B was not correlated with those with a positive caspase 3(P>0.05).Positive expression of FAM96A m RNA and FAM96B m RNA was detected both in GIST and in normal tissues.The results showed that the FAM96A m RNA decreased in comparison with their normal tissue(P=0.00).However,the expression of FAM96B m RNA had no significant difference in all tissue(P>0.05).Conclusions:FAM96A and FAM96B may be potential tumor suppressor genes involved in development of GIST;the decrease and deletion of FAM96A and FAM96B may be used to predict the malignant potential of GIST.The decrease of caspase 3 protein may be related to the formation of GIST.There was no correlation between the expression of FAM96A,FAM96B and the expression of caspase 3 in GIST.