DNA ploidy and c-Kitmutation in gastrointestinal stromal tumors

AIM: To investigate the prognostic significance of c-Kitgen emutation and DNA ploidy in gastointestinal stromal tumors (GISTs).METHODS: A total of 55 cases of GISTs were studied for the expression of c-Kit by immunohistochemistry, and the c-Kit gene mutations in exons 9, 11, 13, and 17 were detected by polymerase chain reaction-single strand confirmation polymarphism (PCR-SSCP) and denaturing high performance liquid chromatography (D-HPLC) techniques. DNA ploidy was determined by flow cytometry.RESULTS: Of the 55 cases of GISTs, 53 cases (96.4%) expressed c-Kit protein. The c-Kit gene mutations of exons 11 and 9 were found in 30 (54.5%) and 7 cases (12.7%),respectively. No mutations were found in exons 13 and 17.DNA aneuploidy was seen in 10 cases (18.2%). The c-Kit mutation positive GISTs were larger in size than the negative GISTs. The aneuploidy tumors were statistically associated with large size, high mitotic counts, high risk groups, high cellularity and severe nuclear atypia, and epithelioid type.There was a tendency that c-Kit mutations were more frequently found in aneuploidy GISTs.CONCLUSION: DNA aneuploidy and c-Kit mutations can be considered as prognostic factors in GISTs.

Immunohistochemical study of hepatic oval cells in human chronic viral hepatitis

AIM: To detect immunohistochemically the presence of oval cells in chronic viral hepatitis with antibody against c-kit. METHODS: We detected oval cells in paraffin embedded liver sections of 3 normal controls and 26 liver samples from patients with chronic viral hepatitis, using immunohistochemistry with antibodies against c-kit, piclass glutathione S-transferase (pi-GST) and cytokeratins 19 (CK19). RESULTS: Oval cells were not observed in normal livers. In chronic viral hepatitis, hepatic oval cells were located predominantly in the periportal region and fibrosis septa,characterized by an ovoid nucleus, small size,and scant cytoplasm. Antibody against stem cell factor receptor, c-kit, had higher sensitivity and specificity than pi-GST and CK19. About 50%-70% of c-kit positive oval cells were stained positively for either pi-GST or CK19. CONCLUSION: Oval cells are frequently detected in human livers with chronic viral hepatitis, suggesting that oval cell proliferation is associated with the liver regeneration in this condition.

Gastrointestinal tumors in transplantation: Two case reports and review of literature

BACKGROUND Gastrointestinal stromal tumors(GISTs)are the most common mesenchymal tumors of the gastrointestinal tract.As most of them harbor a KIT mutation(75%),selective kinase inhibitors are the therapeutic option and show a sustained objective response among patients with metastatic or unresectable GISTs.A wellknown higher risk of neoplasm has been described among renal transplant recipients(RTRs).Nevertheless,only few cases of GIST onset among transplant patients have been reported in the literature.CASE SUMMARY Here,we describe 2 cases of gastric GIST occurring during the follow-up of RTRs.We also review the existing literature concerning GIST occurrence in transplant patients.In total and in association with our 2 cases,16 patients have been reported.The median age was 59.5 years and 69%were male.With a median tumor size of 45 mm,no patient displayed metastatic dissemination at diagnosis.Time from transplantation to diagnosis was highly variable between 5 mo and 21 years.Histopathological data mostly revealed high risk of progression(43%).Death increased to 29%during follow-up.Surgical treatment was systematically performed when the tumor was operable(94%).The use of adjuvant therapy was uncommon(19%).CONCLUSION GISTs represent rare but potentially severe malignant complication among transplant patients.

Effects of electronically stimulating Tianshu(ST 25) and Dachangshu(BL 25), Quchi(LI 11) and Shangjuxu(ST 37) on the expressions of jejunum c-kit protein and c-kit m RNA in rats with functional diarrhea

OBJECTIVE: To investigate the effects of electronically stimulating Tianshu(ST 25) and Dachangshu(BL 25), Quchi(LI 11) and Shangjuxu(ST 37) on the jejunum c-kit protein and c-kit m RNA in rats with functional diarrhea(FD).METHODS: FD models were established through intragastric administration with folium sennae. Experimental rats were then divided into 4 groups:blank group, model group, electroacupuncture group Ⅰ [Tianshu(ST 25) and Dachangshu(BL 25)of both sides] and electroacupuncture group Ⅱ [Quchi(Li 11) and Shangjuxu(ST 37) ofboth sides], 10 in each. After treatment with electroacupuncture for 10 days, The expressions of jejunum c-kit protein and c-kit m RNA in each group were detected with Western blot and Real-Time quantitative real-time polymerase chain reaction(PCR).RESULTS: The expressions of c-kit protein and c-kit m RNA in the model group increased significantly compared to those in the blank group(P < 0.01);the expressions in electroacupuncture group Ⅰsignificantly decreased compared to those in the model group(P < 0.01).CONCLUSION: Our findings suggest that electronically stimulating both Tianshu(ST 25) and Dachangshu(BL 25) significantly increased the expressions of jejunum c-kit protein and c-kit m RNA in FD rats, which means the treatment might have better therapeutic effects on FD.

Prognostic significance of clinicopathologic parameters in gastrointestinal stromal tumors:a study of 156 cases

The biological behavior of gastrointestinal stromal tumors(GISTs)are highly variable.To invest-igate the biological behavior of GIST,we collected 83 cases of gastric and 62 cases of small intestinal GIST from the Department of Pathology of the Chinese PLA General Hospital.The parameters include age,primary tumor location,tumor diameter,mitotic index,tumor necrosis,risk assessment,clinical stage and the c-kit exon 11 muta-tion.All these were analyzed in 105 cases along with the follow-up data and tested by log rank and COX hazard proportional model.We find that the average age of gast-ric GIST was 55.4 years.Of the 62 cases that were fol-lowed up,17 cases had metastasis or recurrence and the 5-year survival rate was(66.51±17.06)%.For the small intestinal GIST,the average age was 50.6 years and 43 cases were followed up.Of these,22 cases had meta-stasis or recurrence and the 5-year survival rate was(61.76±18.30)%.Small intestinal GIST was more fre-quently associated with metastasis and tumor relapse than gastric GIST(x^(2)=56.131,P=0.013).For gastric GIST,patients younger than 50 years(P=0.046),the advanced clinical stage(P=0.0001),the large tumor diameter(P=0.0001),a high mitotic index(P=0.0001),necrosis(P=0.0001)and a high risk grade(P=0.004)were all correlated with a lower survival rate.The COX hazard proportional model revealed that advanced clinical stage(P=0.001),large tumor size(P=0.001),a high mitotic index(P=0.002)and the high risk grade(P=0.018)indi-cated a poorer prognosis in gastric GIST.For small intest-inal GIST,necrosis(P=0.036)and advanced clinical stage(P=0.010)were associated with lower survival rates and the clinical stage was shown to be an independent prognostic indicator.A total of 25 cases harbored muta-tions in c-kit exon 11.The frequency of c-kit mutation was 32%and 22.5%for gastric and small intestinal GIST,respectively.In gastric GIST,the mutated c-kit was pre-dominant in patients older than 50 years of age.But in the small intestinal GIST,the mutated c-kit was predominant in the age group of 40-49 years.In conclusion,for gastric GIST,clinical stage,tumor size,mitotic index,and risk grade are the prognostic indicators.For small intestinal GIST,necrosis and clinical stage are the prognostic indi-cators.Small intestinal GIST are more aggressive than gastric GIST.The occurrence of c-kit mutation may cor-relate with the age of patients.