Bcl-2 protein and prognosis in patients with potentially curable non-small-cell lung cancer.

The bcl-2 proto-oncogene functions as a cell death suppressor, and its expression prolongs cell survival by blocking apoptosis. Data available on the clinical relevance of bcl-2 protein expression in patients with non-small-cell lung cancer (NSCLC) are controversial. We analysed the role of bcl-2 protein expression on 6-year relapse-free survival in 229 patients with stage I-IIIa NSCLC (101 squamous cell carcinomas and 128 adenocarcinomas) subjected to surgery, with curative intent. Immunohistochemical analysis was performed on archival material by using a monoclonal antibody anti-bcl-2 (clone 124). Bcl-2 protein expression, which was detected in 22% of the cases, was significantly related to stage, histology and grading, and was an indicator of clinical outcome. The probability of relapse-free survival at 6 years was longer for patients with bcl-2-positive tumours (74%) than for those with bcl-2-negative tumours (57%) (P=0.02). This finding was mainly evident for the subgroups of patients with stage IIIa tumours (P=0.05), squamous cell carcinoma (P=0.03) or moderately/poorly differentiated tumours (P=0.02). However, multivariate analysis by Weibull's regression model indicated that bcl-2 protein expression was not an independent prognostic risk factor in patients with curable NSCLC when the information provided by stage was available.

Cell proliferation-related markers in colorectal liver metastases: correlation with patient prognosis.

PURPOSE: We analyzed the relation between phenotypic (DNA ploidy) and functional markers (S-phase cell fraction, p53, and bcl-2 protein expression) and defined their relevance on clinical outcome on a retrospective series of radically resected liver metastases from colorectal cancer. PATIENTS AND METHODS: Among 104 patients with resectable liver metastases from colorectal cancer, DNA ploidy was determined by flow cytometry, 3H-thymidine labeling index (TLI) by autoradiography, and expression of p53 and bcl-2 by immunohistochemistry. RESULTS: TLI was a significant indicator for relapse at 4 years from radical surgery, DNA ploidy was a suggestive indicator of clinical outcome, and p53 and bcl-2 expression provided no clinical information. By multivariate analysis, cell proliferation rate and Dukes' stage remained independent prognostic parameters. In the most representative subgroup of patients with H1 liver lesions (86 cases), TLI was always associated with relapse, and DNA ploidy and p53 expression provided discriminant information within slowly proliferating liver lesions. CONCLUSION: Tumor-cell proliferation of liver lesions should be used with stage of the primary colorectal cancer for a more accurate prognosis in patients submitted to curative hepatic resection.

MIB-1 and S-phase cell fraction predict survival in non-Hodgkin's lymphomas.

The monoclonal antibody anti-Ki67 is used to detect proliferating cells, but its main limitation is the requirement of fresh-frozen material. On a series of patients with non-Hodgkin's lymphoma, we used a Ki67 equivalent monoclonal antibody, the recently proposed MIB-1, on formalin-fixed histopathological material using microwave antigen retrieval. MIB-1 expression was analysed in relation to other proliferation indices, such as autoradiographic H-thymidine labelling index (HTL1) and flow cytometric S-phase cell fraction (FCM-S) and to pathological status. Moreover, the prognostic relevance of the cell kinetic indices was defined in uni- and multivariate analyses including histology and tumour stage. The relationship between MIB-1 index and the other proliferation indices was statistically significant even though the correlation coefficient was around 0.6. The MIB-1 index was also related to the REAL (Revised European American Lymphoma) classification, but not to the Ann Arbor stage classification. Univariate analysis showed that the MIB-1 index was a significant predictor of 6-year survival in the overall series and in distinctly analysed low-grade and high-grade lymphoma subgroups. With regard to S-phase indices, HTLI was a powerful prognosticator in patients with high-grade histologies and FCM-S in patients with low-grade histologies. Multivariate analyses revealed that MIB-1 index, HTLI and FCM-S retained their prognostic significance independent of histology. In conclusion, the MIB-1 antibody provides prognostic information in non-Hodgkin's lymphomas and has the main advantage that it can be used in formalin-fixed, paraffin-embedded specimens.

P53 expression, DNA ploidy and S-phase cell fraction in operable locally advanced non-small-cell lung cancer.

The identification of biomarkers to complement pathological stage for a more accurate prognosis and help clinicians decide on treatment is still an open problem for patients with lung cancer. Expression of P53 protein was detected by an immunohistochemical approach using the monoclonal antibody PAb1801 on paraffin-embedded sections of tumours obtained surgically from 102 stage II - IIIa patients with non-small-cell lung cancer (52 squamous cell carcinomas, 50 adenocarcinomas). [3H]Thymidine labelling index, an indicator of the S-phase cell fraction, was evaluated on histological sections of [3H]thymidine-labelled tumour samples. DNA ploidy was defined by flow cytometric analysis on frozen tumour tissue. The biomarkers, histology and pathological stage were analysed in relation to relapse-free survival in univariate and multivariate analyses. Stage and interaction between [3H]thymidine labelling index and histology provided significant prognostic information for the overall series. [3H]thymidine labelling index was an independent prognostic indicator of 3 year relapse-free survival in patients with adenocarcinoma. The results indicate the importance of cell proliferation to complement prognostic information provided by pathological stage in patients with stage II-IIIa adenocarcinomas.