P53 and heat shock protein 70 expressions in colorectal adenocarcinoma

OBJECTIVE: To examine the localization and over expression of heat shock protein 70 (HSP70) and p53 in patients with colorectal cancer and compared it with control tissue (including normal colon tissue).

METHODS: This was a retrospective study of 60 patients with colorectal adenocarcinoma at the Jordan University of Science and Technology (JUST), Irbid, Jordan from 1997 to 2000. The Pathology Department at JUST is the chief provider of surgical pathology services in the north of Jordan. It receives specimens from both government and private hospitals. Immunohistochemistry was the technique of choice.

RESULTS: The HSP70 was over expressed more highly in colorectal cancers than in the control tissue. Immuno-histochemistry showed that over expression of HSP70 had no statistically significant difference with any of the different prognostic factors assessed, mainly the grade and the stage. The p53 was over expressed in 60% of the cases. Control tissue (normal colon) was negative, p53, cell-cycle-related oncogene product, was strongly over expressed in the nuclei of the cancer cells of the cancer tissue. We found no significant difference in terms of size, patient age, lymph node state, and stage. The rate of expression was significantly less in high grade tumors than in intermediate and low grade ones.

CONCLUSION: The strong expression however, may be valuable in estimating a prognosis for patients with colo-rectal carcinoma.