Study On Correlation Between HO-1 Gene And Kaposi's Sarcoma

Objective: The purpose of this study is to probe into the function of HO-1 in tumorigenesis and development of KS, and the possible mechanism in KS pathogenesis.Methods: We Collected tumour tissues and vicinal normal skin tissues from 21 cases of KS patients in XIN JIANG, and collected normal skin tissues from 14 cases of non-KS patients as control。Then we applied Real-time PCR and immunohistochemical technique to detect HO-1 mRNA and protein expression in these samples. Antiapoptotic pathway of HO-1 from tissue level was detected by immunohistochemical Envision technique for p38 and TNFa and the in situ end labeling(TUNEL) for cell apoptotic index(AI). Antiapoptotic pathway of HO-1 from cell level was detected by flow cytometry for apoptosis after 24h given Hemin and/or Znpp and/or SB203580, and meantime the expression of HO-1,p38 and TNFa was detected by western-blot.Results: (1) Real Time PCR results by relative quantitation method of double standard curves revealed that the HO-1 mRNA expression in tumor tissues of KS patients was 14.14±11.64 and the HO-1 mRNA expression in normal skin tissues of KS patients was 5.5±8.05. HO-1mRNA expre- ssion in tumor tissues of KS patients were higher than that in normal skin tissues, the difference had statistical significance(t=4.074,p<0.01). (2) Immunohistochemical results found that the positive expression rate of HO-1 protein in KS was significantly higher than that in normal skin tissues(x2 =15.56, P<0.01) and the difference of positive reaction degree between KS and normal skin tissues had statistical significance (t=11.305,P<0.01). (3) Immunohistochemical results fou- nd that the expression levels of p38 were apparently higher than those of control group(t=9.044,P<0.01). AI of KS by TUNEL method were significantly higher than that in normal skin tissues(t=3.183,P<0.01). However, expression levels of TNFa in seven cases of KS were positive, and seven cases were negtive. There was no significance. (4) Apoptotic ratio by flow cytometry and western-blot'results revealed that HO-1 and p38 protein were overexpression and TNFa prot- ein was lower expression in BCBL1 cells. Apoptotic ratio was 4.37 percent after Hemin was added into BCBL1 cells for 24h. Apoptotic ratio was 31.81 percent after Znpp affected BCBL1 cells for 24h. Apoptotic ratio was 19.71 percent after SB203580 was given into BCBL1 cells for 24h.From the results we found that HO-1 could protect BCBL1 cells from apoptosis induced by TNFa. Apo- ptotic ratio in cells assumed negative correlation with expression of HO-1.Conclusion: (1) HO-1 mRNA and protein expression in tumor tissues of KS patients were higher than that in normal skin tissues. (2)The overexpression of HO-1 also resided in HHV-8 infected cells.(3) HO-1 gene correlated with the tumorigenesis and development of KS.