Correlation of tissue transglutaminase expression on breast cancer tissue with time to relapse, overall survival, and clinical and molecular prognostic factors: a preliminary report.

PURPOSE: To correlate tissue transglutaminase (TTG) expression with the expression of molecules with prognostic significance in breast cancer patients and with classical clinical parameters (disease stage, histological grade, overall survival (OS), relapse rate, disease progression and time to treatment failure-TTF). PATIENTS AND METHODS: Paraffin-embedded tissue specimens from 68 breast cancer patients were studied retrospectively for TTG expression, estrogen (ER) and progesterone (PG) receptors, c-erbB-2, p53, Bcl-2, and Ki-67. Sixty-seven patients were females (mean age 60.5 years). Histology was ductal carcinoma in 53 (inflammatory in 2 and mucinous in 1 of them), lobular in 13 and tubular in 2 cases. Grade was 1 and 2 in 45 cases and 3 in 23. Forty-six patients had early-stage disease (I - IIB) and 22 advanced (IIIA - IV). RESULTS: Fifty patients had at least 1 favorable molecular prognostic factor while all but 3 had at least 1 unfavorable prognostic factor. Twenty-nine (42.6%) patients have relapsed so far (mean TTF 31.4 months). Fifty-two (76.5%) patients are still alive (mean OS 38.5 months). Of the 59 patients with nodal and/or metastatic disease 54 were expressing TTG and 32 Bcl-2. Five were not expressing either one while 22 were expressing both. Of the 9 patients without nodal and/or metastatic disease all but one were expressing TTG and Bcl-2. Analyzing these subgroups of patients there was sufficient evidence that TTG expression was correlated with a trend for prolonged survival both in patients with localized and extensive disease, while the coexpression with Bcl-2 was correlated with a trend for prolongation of TTF and OS, both in relapsing and nonrelapsing patients. However, these differences did not reach statistical significance. Similar comparisons of TTG expression with the presence of adverse prognostic factors verified a beneficial effect of TTG expression on OS in all subgroups. CONCLUSION: Our data suggest that TTG is an independent favorable prognostic factor for survival, possibly enhancing the apoptotic effect of chemotherapy.