Little information is available on the clinical significance of cancer-related genes such as KRAS, NRAS, BRAF, PIK3CA and TP53 in nonmetastatic rectal cancer.
Fifty patients with locally advanced rectal cancer were treated with preoperative radiotherapy combined with mitomycin C and capecitabine. p21 and p53 immumohistochemical staining was performed on pretreatment biopsies and the results were compared with tumor regression according to grading systems by Dworak (TRG grades) and by Wheeler (RCRG grades).
The associations between p53 protein expression and TP53 polymorphism, biological behavior and prognosis in low rectal cancer were systematically analyzed.
Utilizing a novel in silico clonal evolution algorithm, we identified common tumor-initiating events involving APC, KRAS and TP53 genes in RCC, LCC and rectal cancers.
TP53 was associated with colorectal cancer, but the different value levels of mRNA expression were not associated with survival rate of colon and rectal cancer.
Thus, our current meta-analysis indicates no evidence for the association between the p53Arg72Pro polymorphism and CRC risk in the Asian population, but significant association in Chinese population, especially for rectal cancer and in men.
These results suggest that the TP53Arg72Pro polymorphism CC genotype may contribute to an increased risk of CRC, especially for rectal cancer and among Asians.
Expression of p53 mRNA is a useful predictor of survival in patients with stage III or rectal cancers, with a significant association with CD44 mRNA expression.
Our objective was to establish a correlation between specific KRAS mutations and rectal cancer response to CRT and to investigate if the correlation was related to a different association between KRAS and TP53 mutations.
Without correction for multiple testing, one polymorphism in GPX2 and three polymorphisms in GPX3 were associated with a significant risk reduction for rectal cancer at α = 0.05, specifically for rectal cancers with TP53 mutations.
The results of the present meta-analysis indicate that P53 status is a predictive factor for response in rectal cancer patient undergoing neoadjuvant radiation-based therapy.
In this comprehensive study of genetic variability in IL23R across the spectrum of colorectal carcinogenesis, as well as within colon and rectal tumor molecular subtypes, we observed associations between SNPs in IL23R and risk of rectal cancer: the 88413 C>A (rs10889675) and 69450 C>A (rs7542081) polymorphisms were associated with decreased rectal cancer risk overall (p-trend=0.04 and 0.05 respectively), and specifically with rectal tumors bearing a TP53 mutation (88413 CA/AA vs. CC OR: 0.66; 95% CI: 0.46-94; 69450 CA/AA vs. CC OR: 0.60; 95% CI: 0.37-0.98).
The predictive capacities of PrxI and p53 were also assessed by relating the immunohistochemical staining of a retrospective series of rectal cancer cases to the clinical outcome.
This study was designed to determine whether pretreatment cyclooxygenase-2 and p53 protein expression were predictors of histopathologic response in patients with rectal cancer treated with preoperative short-term chemoradiotherapy.