Twenty cases of gastric cancer and five cases of esophageal cancer were also analyzed for p53 gene mutation by polymerase chain reaction and direct nucleotide sequencing.
Polymorphisms and mutations found in the regions flanking exons 5 to 8 of the TP53 gene in a population at high risk for esophageal cancer in South Africa.
Out of a total of 101 biopsy specimens of carcinoma esophagus analysed, the frequency of HPV was found to be the highest 14/32 (44%) in Dibrugarh followed by 33% (11/33) in Kashmir, but, interestingly, no high-risk HPV could be detected in New Delhi patients who showed the highest frequency (30.6%) of p53 mutation as against only 12.5% in Dibrugarh and 6.1% in Kashmir.
The genes CDKN2B (MTS2) and CDKN2 (MTS1) encoding the proteins p15 and p16 are both located on chromosomal band 9p21, a locus at which frequent homozygous and heterozygous deletions occur in many primary human tumors, including esophageal carcinoma.
To understand the mutation spectrum and possible causative factors of esophageal cancer in this area, surgically resected human primary esophageal carcinomas from Linxian county were analyzed for p53 gene mutations in exons 5, 6, 7, and 8.
TP53 gene mutations are not common events in CE, but are frequent in ESCC, and as polymorphisms of TP53 and FHIT may confer a greater risk for the development of esophageal carcinoma, further studies are required.
These results confirm the high frequency of biallelic p53 mutations in esophageal carcinoma and strongly suggest that their biological consequence is the complete alteration of the transactivation of genes involved in the cell cycle and apoptosis, which indicates that p53 alteration is a key event in esophagus carcinogenesis.
These results suggest that several putative tumor suppressor genes, in addition to the cyclin D and TP53 genes that are sometimes mutated in esophageal carcinomas, may be associated with development and/or progression of esophageal cancer.
In previous studies, we have shown that allelic loss on chromosome 17p, on which the p53 gene is located, is very frequent, and loss-of-function mutations of the p53 gene are closely associated with the tumorigenesis of esophageal cancer.
In summary, p73 G4C14-to-A4T14 polymorphism but not the p53 intron3 16 bp duplication polymorphism is associated with EC and its clinical characteristics in northern Indian population.
Therefore, our results suggested that the survivin expression depended on the p53 status and the C allele in the survivin promoter polymorphism -625G/C might increase the possibility of the survivin overexpression in esophageal cancer patients.
The sensitivity of the p53 fluorescent in situ hybridization probe was13.3 % for any abnormality, 10 % for intestinal metaplasia, and 0 % for dysplasia or esophageal cancer.
The importance of p53 gene mutations in the pathogenesis of human esophageal carcinoma is well established, but it is still controversial whether the presence of p53 mutations adversely affects individual patient prognosis.
Forty-five patients diagnosed with esophageal carcinoma (confirmed squamous cell carcinoma) were randomly assigned to one of two study arms: treatment group: rAd2p53 gene therapy + RT (n = 22); and control group: radiotherapy (n = 23).
To investigate the relationship between p53 codon 72 polymorphism and human papillomavirus (HPV) type 16 infection in Kazakh's esophageal cancer (EC) in Xinjiang, China.
These findings suggest that loss or mutations of the p16 gene are involved in most esophageal cancers and that mutation of this gene plays a critical role in the development of esophageal cancer.
When all 11 studies were pooled into the analysis, an increased esophageal cancer risk was significantly associated with the Pro variant of TP53Arg72Pro in three genetic comparison models [odds ratio (OR)Pro vs. Arg=1.21, 95% confidence interval (CI): 1.05-1.39, POR=0.009; ORDominant genetic model=1.22, 95% CI: 1.09-1.37, POR=0.001; ORHomozygote model=1.40, 95% CI: 1.05-1.87, POR=0.024].