The potential for serum p53 to predict the response to chemotherapy of patients with gastric cancer

The predictors of response to neoadjuvant chemotherapy in patients with locally advanced gastric cancer

BACKGROUND

Chemotherapy-sensitivity test is crucial to screen out patients who are insensitive to the treatment and to avoid unnecessary preoperative chemotherapy.

OBJECTIVE

To investigate the predictors for the response to mFOLFOX7 neoadjuvant chemotherapy (NACT) in advanced gastric cancer.

METHODS

The expression of C-met, EGFR, HER2, Ki-67, MMP7, P53 and TOPOII in tumor tissue from 53 locally advanced gastric cancer patients (AGC) was detected by immunohistochemistry. The relationship between tumor marker expression and the efficacy of NACT was determined by chi-square test and multivariate logistic regression analysis. The relationship between the combined expression of HER2 and P53 and the efficacy of NACT was further analyzed by chi-square test.

RESULTS

The overall response rate was 52.8% (28/53). There were no significant differences of tumor markers' expression before and after chemotherapy (P> 0.05). The response rate in HER2-positive patients (83.33%) was significantly higher than that in HER2-negative patients (43.90%, P= 0.016), whereas the response rate in P53-positive patients (35.71%) was significantly lower than that in P53-negative patients (72.0%, P= 0.008). Moreover, the response rate was the highest in the patients who were positive for HER2 but negative for P53.

CONCLUSION

HER2 and P53 were identified as independent predictors for the response to mFOLFOX7 NACT in AGC.

Synergistic role between p53 and JWA: prognostic and predictive biomarkers in gastric cancer

Expression of p53 appears to be correlated to prognosis in patients with malignancy, but its role in gastric carcinoma has remained controversial. Recently we reported that JWA, an ADP-ribosylation-like factor 6 interacting protein 5 (ARL6ip5), was both prognostic for overall survival and predictive for platinum-based treatment of gastric cancer. In this study, we aimed to investigate p53 expression as a prognostic and predictive marker in resectable gastric cancer, alone and in combination with JWA. Expression of p53 was examined in three large patient cohorts (total n = 1155) of gastric cancer. High expression of p53 was significantly correlated with unfavorable clinicopathologic parameters and decreased overall patient survival. Furthermore, patients with high p53 expression in tumors acquired remarkable survival benefit from adjuvant first-line platinum-based-chemotherapy. The synergy between p53 and JWA in predicting patient outcome was demonstrated, while no significantly elevated predictive value concerning chemotherapy was observed. Thus, p53 expression is a potent prognostic and predictive factor for resectable gastric cancer with adjuvant platinum-based chemotherapy. A combined effect of p53 with JWA as efficient prognostic indicators was found for the first time.