Expression of p53, bcl-2, and bax as predictors of response to radiotherapy in esophageal cancer

The sensitivity of cancers to radiotherapy or chemotherapy may be influence d by susceptibility to apoptosis. We evaluated whether expression of three proteins regulating apoptosis, p53, bcl-2, and bax, could predict the effec t of radiotherapy in esophageal cancers, We used immunohistochemical staini ng for these protein regulators of apoptosis to study biopsy specimens obta ined from 25 patients with esophageal squamous cell carcinoma before they u nderwent preoperative radiotherapy. Effectiveness of radiotherapy was asses sed by barium esophagography, esophagoscopy, and computed tomography. Radio therapy was effective in 12 patients and ineffective in 13 patients, Biopsy specimens from the 25 patients showed expression of p53, bcl-2, and bax to be 48.0%, 32.0%, and 76.0% respectively, Effectiveness of radiotherapy was correlated with p53 expression (p = 0.047), but bcl-2 and bax expression s howed no relationship to effectiveness of radiotherapy. Expression of p53 p rotein in biopsy specimens may predict effectiveness of preoperative radiot herapy in esophageal cancers.