The prognostic value of p27 in gastric cancer

Objectives: p27 is a cyclin-dependent kinase inhibitor and a putative tumor suppressor preventing progression of the cell cycle from G1 phase. Recent studies have suggested loss of p27 to correlate with poor prognosis in patients with a variety of solid tumors. Results in gastric cancer are contradictory. We therefore decided to study the potential of p27 as a prognostic marker in a consecutively surgically treated, single-institution series of patients. Methods: Using a monoclonal antibody against p27, immunohistochemistry was performed in paraffin-embedded tumor specimens from 316 patients. Results: Loss of p27 immunoreactivity (less than or equal to 5% of the cancer cell nuclei positive) was observed in 241 (76%) out of 316 stained tumors. We observed no significant correlation between the expression of p27 and stage of disease, tumor size, depth of tumor invasion, lymph node metastases, distant metastases, Lauren classification, Borrmann type, grade of differentiation, age or gender. There was no significant difference in gastric cancer specific overall survival between patients with low and high p27 expression. Conclusion: Our results add further doubt to the usefulness of p27 as a prognostic marker in gastric cancer.