Correlation between mutation of p53 gene 2-4 exons from peripheral blood and HPV16 positive cervical cancer susceptibility and clinical significance

Abstract

Objective: To detect mutations of p53 gene 2-4 exons from peripheral blood and to explore their relevance in HPV16-positive cervical cancer susceptibility and clinical significance. Methods: Collected firstly cases from the Third Affiliated Hospital of Kunming Medical University from October 2012 to April 2014, included 167 cases HPV16-postive cervical cancer and 160 cases HPV-negative healthy women. Genomic DNA from the host peripheral venous blood was taken, mutations of p53 gene 2-4 exons were analyzed with software DNAstar after PCR and bidirectional sequencing. Meanwhile, mutations of p53 gene 2-4 exons among different clinicopathological characteristics in HPV16-postive cervical cancer were distinguished. Results: (1) Three mutations and an 16-bp insertion/deletion sequences were found in p53 gene exons 2-4, included C/G mutation of single nucleotide polymorphism (SNP) 11827 in intron2, A/C mutation of SNP11992 in intron3, C/G mutation in codon 72 (rs1042522) of exon4 and 16-bp (acctggagggctgggg) repeat insertion or deletion in intron3 (rs17878362), while deletion recorded as A1, insertion recorded as A2. No significant differences were found in each point allele and genotype frequency (P>0.05) . (2) Stratified analysis for cervical cancer group resulted with some differences. Compared group of non-squamous carcinoma with squamous carcinoma group, there were obviously decreased in allete A2 [11.8% (4/34) vs 3.5% (10/284) ; χ(2)=4.90, P=0.027], genotype A1A2 [4/17 vs 7.0% (10/142) ; χ(2)=5.14, P=0.023], and haplotype C-A2 [11.8% (4/34) vs 3.5% (10/284) ; χ(2)=4.91, P=0.027]. Compared with poorly differentiated group, allele C of SNP11827 and rs1042522 were obviously decreased in medium high differentiation group [50.8% (61/120) vs 38.8% (62/160) ; χ(2)=4.07, P=0.044], while haplotype G-A1 were apparently higher [49.2% (59/120) vs 61.2% (98/160) ; χ(2)=4.07, P=0.044], genotype GG of SNP11827 and rs1042522 were obviously decreased in superficial myometrial invasion depth group than that in deep myometrial invasion depth group [46.3% (25/54) vs 21.1% (8/38) ; χ(2)=7.06, P=0.029]. No significant differences were found between stage Ⅰ and Ⅱ, pelvic lymph node metastasis or not (all P>0.05) . Conclusions: No obvious correlation is found between polymorphisms in exons 2-4 of p53 gene and susceptibility of HPV16-postive cervical cancer. But the patient with allete C and A2, genotype GG and A1A2, haplotype C-A2 and G-A1 may be increase risk of poorly differentiation, deep muscular invasion and bad pathological type. Analysis of p53 gene polymorphism may be provide a basis for the prognosis evaluation and individualized treatment of cervical cancer.