Expression Of K-ras、p53genic Mutation And Pax2、P53、Ki-67Protein In Ovarian Serous Tumors

[Objective] To study the k-ras and P53genemutationsinovarianserouscarcinoma, aswell as the expression characteristics of Pax2, P53,Ki67proteins.To explore the valueof two grading systems in the clinical and pathological diagnosis of serous ovariancancer, so as to increase the diagnosis accuracy and provide reasonable clinical basis.[Method] According to the grading standards of the two classification systemsovarian serous proposed by Malpica et.al[3]in the American MD Anderson CancerCenter, we chose25cases low level ovarian serous carcinoma and38cases high levelovarian serous carcinoma. respectively, as the experimental group and the other20cases of ovarian serous cystadenoma was selected as a control group. Polymerasechain reaction (PCR)amplification and direct sequencing were employed to detectmutation of first exon in K-ras gene. Using the polymerase chain reaction-restrictedfragment length polymorphism (PCR-RFLP) were used to detect the mutation ofArg72codon in P53gene, the3th intron and the6th intron promoters. EnVisionmethod in Immunohistochemistry (IHC) was applied to assess the expression levels ofPax2, P53, K-i67protein. Two independent samplest-test and chi-square test werecarried out withSPSS18.0statistical software to evaluate and compare each group genemutations and protein positive expression rate, and toa nalysis their correlation withlow and high-level serous carcinoma and the clinical and pathological features.[Results] 1Low-level set of ovarian serous carcinoma showed significantly higher K-rasmutation rate(28.0%) than the high-level group(5.3%)(P <0.05), and the K-rasmutation in serous cystadenoma was not detected.2Distributions of three genotypes of codon72in P53(CC, CG, GG) and C, G alleleshowed no difference(P>0.005) in the three groups. The difference in the distributionof third intron containing A ’genotype in low levels ovarian serous carcinoma groupand high levels ovarian serous carcinoma group was statistically significant(P<0.05).Three cases of A’ A’homozygous mutation in the3rdintron occurred in thegroup of high-level serous carcinoma, which was not detected in low-levelgroup.5cases of AA’homozygous mutation in the3rdintron occurred in the high-level serouscarcinoma group, and no such mutation was detected in the low-level group.Frequency distribution of the three genotypes(NN, NN ’, N’ N ’) in the6thintronand N,N’allele in ovarian serous carcinoma and ovarian serous cystadenoma group havestatistically differences(P <0.05).Four cases of N’N’ homozygous mutationin the6thintron occurred in the group of high-level serous carcinoma, no N’N’ homozygousmutation in the6thintron was detected in the low-level group.3The expression rates of P53protein strongly positive rate in the serous carcinomahigh-level were28%and63.3%, the difference was statistically significant(P <0.05),and it was not expressed in serous cystadenoma.4The expression rate of Pax2protein in the low and the high levelwas48%and18.4%, respectively, and the difference was statistically significant(P<0.05). Expression rate was30%in serous cystadenoma, whose difference with theexpression rate in ovarian serous carcinoma group was statistically significant(P<0.05).5The positive rate of Ki-67proteininthelow-and high-level group were16% and60.5%(P <0.05), respectively, and was not expressed in serous cystadenoma.6The positive rates of P53, Pax2, Ki-67protein are unaffected whether in volvingboth ovaries, lymph node metastasis, tumor size, and age-independent correlation(P>0.05).[Conclusion]1High and low level ovarian serous carcinoma have different phenotype in Molecular genetics and immune.2In ovarian serous carcinoma, low-grade serous carcinoma occurs mainlyinthe12thand13thcodon point in the first exon of K-ras gene; mainly the3rdand6thintronmutation in P53gene occurs in the high-level serouscarcinoma. It is indicated that different gene mutation point plays a role inthe accurrence and development of ovarian serous carcinomain low, and highlevels ovarian serous carcinoma.3The expression difference of P53, Pax2and Ki-67protein in low-andhigh-level serous carcinoma was statistically significant(P <0.05), which canbe used as molecular markers in serous ovarian cancer treatment.4Serous ovarian cancer isa heterogeneous group of tumors, a two-tier gradingsystem can reflect the characteristics of the tumor, showing its value inguiding clinical treatment.