Serum anti-p53 antibody as a tumour marker for colorectal cancer screening

Inducible Nitric Oxide Synthase in the Carcinogenesis of Gastrointestinal Cancers

SIGNIFICANCE

Gastrointestinal (GI) cancer taken together constitutes one of the most common cancers worldwide with a broad range of etiological mechanisms. In this review, we have examined the impact of nitric oxide (NO) on the etiology of colon, colorectal, gastric, esophageal, and liver cancers. Recent Advances: Despite differences in etiology, initiation, and progression, chronic inflammation has been shown to be a common element within these cancers showing interactions of numerous pathways. NO generated at the inflammatory site contributes to the initiation and progression of disease. The amount of NO generated, time, and site vary and are an important determinant of the biological effects initiated. Among the nitric oxide synthase enzymes, the inducible isoform has the most diverse range, participating in numerous carcinogenic processes. There is emerging evidence showing that inducible nitric oxide synthase (NOS2) plays a central role in the process of tumor initiation and/or development.

CRITICAL ISSUES

Redox inflammation through NOS2 and cyclooxygenase-2 participates in driving the mechanisms of initiation and progression in GI cancers.

FUTURE DIRECTIONS

Understanding the underlying mechanism involved in NOS2 activation can provide new insights into important prevention and treatment strategies. Antioxid. Redox Signal. 26, 1059-1077.

Expression and clinicopathologic significance of TUFM and p53 for the normal-adenoma-carcinoma sequence in colorectal epithelia

BACKGROUND

Evidence indicates that most cases of colorectal carcinoma (CRC) develop from adenoma. A previous study demonstrated that mitochondrial Tu translation elongation factor (TUFM) might serve as an independent prognostic factor for colorectal cancer. However, the expression and function of TUFM in the normal-adenoma-cancer sequence have not been reported. In this study, we investigated the clinicopathologic significance of TUFM and p53 expression for the normal-adenoma-carcinoma sequence in colorectal epithelia and evaluated the roles of TUFM during the progression of colorectal tumors.

METHODS

Paraffin-embedded specimens from 261 colorectal normal mucosa samples, 157 adenomas, and 104 early carcinomas were analyzed for TUFM and p53 expression by immunohistochemistry.

RESULTS

Expression of TUFM and p53 was significantly increased during the colorectal normal-adenoma-carcinoma sequence (all P < 0.05). The expression of TUFM and p53 was associated with histologic type of adenomas (P = 0.028; P = 0.001) and grade of dysplasia (all P = 0.001). Expression of TUFM was positively correlated with that of p53 (r = 0.319, P = 0.001).

CONCLUSIONS

Upregulated TUFM expression may play an important role in the transformation from colorectal normal mucosa to carcinoma through adenoma. Combined immunohistochemical detection of TUFM and p53 may be useful for evaluating the biological behavior of colorectal adenoma.