Immunohistochemical Localization of Wild-type EGFR, E746-A750 Frame Deletion in Exon 19, and L858R Point Mutation in Exon 21 in Triple-negative Breast Cancer.

AIM: This study evaluated wild-type EGFR, E746-A750 frame deletion in exon 19, and L858R point mutation in exon 21 by immunohistochemistry in patients with triple-negative breast cancer (TNBC). METHODS: A retrospective study included 99 untreated early-stage and advanced-stage TNBC patients. Immunohistochemical localization of wild-type EGFR, EGFR E746-A750 deletion in exon 19, and EGFR L858R mutation in exon 21 was performed on formalin-fixed paraffin-embedded tissue blocks using mutation-specific primary antibodies. RESULTS: EGFR protein expression was noted in 27% (27/99) of patients with 2+ or 3+ staining intensity in 7% (7/99) of patients. Significant correlation of EGFR protein expression with subgroups of clinicopathologic parameters was not found. In univariate and multivariate survival analysis, high EGFR expression (2+ or 3+) emerged as a significant prognostic factor for disease-free survival. With respect to mutation status, exon 19 deletion was observed in 3% (3/99) of patients. One patient with exon 19 deletion having high EGFR protein (2+) expression developed lung metastasis, whereas the other 2 patients with exon 19 deletion had low EGFR protein (1+) expression and remained disease free during the study period. CONCLUSIONS: EGFR protein overexpression was observed in one fourth of TNBCs with very low incidence of EGFR-activating mutations in patients of western India.

Role of PRL-3, Snail, Cytokeratin and Vimentin expression in epithelial mesenchymal transition in breast carcinoma.

AIM: To study epithelial mesenchymal transition (EMT) in breast cancer, molecules such as PRL-3, Snail, Cytokeratin and Vimentin involved in EMT were evaluated. MATERIALS AND METHODS: In this study, m-RNA expression of PRL3 and Snail by RT PCR, protein expression of PRL-3, Snail, Cytokeratin and Vimentin by immunohistochemistry were evaluated on paraffin-embedded tissue sections of 100 patients with breast cancer. RESULTS: PRL3 m-RNA expression (above cut off level > 2487301.00) and PRL-3 protein expression was noted in 52% and 70% of breast carcinoma patients, respectively. The higher incidence of PRL3 protein than m-RNA expression could be due to post translation modification. Further, Snail m-RNA expression (above cut off level > 1285142.00) and Snail protein expression was noted in 53% and 54% of breast cancer patients respectively and Snail protein expression was found significantly higher in patients with pre-menopausal status. The loss of cytokeratin expression in 32% and gain of vimentin expression in 17% was noted in these patients. Vimentin expression was found significantly higher in patients with stage IV disease, BR score 4 and PR negativity. In multivariate survival analysis, Vimentin expression found as strong indicator of biologically aggressive breast cancer predicting reduced disease free survival (DFS) and overall survival (OS). CONCLUSION: In our study reveals that Vimentin expression emerged as significant biomarker for predicting reduced DFS and OS in breast cancer. The study proposes routine evaluation of Vimentin with other predictive parameters can allow use of EMT inhibitors with conventional therapy to revert EMT in breast cancer.

Clinical relevance of FLT3 receptor protein expression in Indian patients with acute leukemia.

AIM: FLT3 is a receptor tyrosine kinase that plays an important role in the pathogenesis of leukemia. The present study aimed to evaluate the role of FLT3 protein in patients with acute leukemia. METHOD: FLT3 protein was quantified by flow cytometry on leukemic blasts using CD135 antibody in 160 patients with acute leukemia. RESULTS: We demonstrated FLT3 protein expression (>20%) in 82% of acute myeloid leukemia (AML), 60% of B-lineage acute lymphoblastic leukemia (B-ALL), 23% of T-lineage acute lymphoblastic leukemia (T-ALL) and 80% of biphenotypic leukemia. Further, FLT3 expression was seen to be significantly higher in AMLM2, M4, and M5 than in AMLM3. In B-ALL, FLT3 was found to be higher in pro-B-ALL and lower in early B-ALL. A CD34 expression >20% was associated with FLT3 positive B-ALL. When correlated with disease status, all patients in the relapsed AML group had FLT3 > 20% at diagnosis. Unlike AML, the relapsed group of B-ALL showed a lower incidence of FLT3 than the remission group. CONCLUSION: In summary, our data imply that there is frequent overexpression of the FLT3 protein in AML and B-ALL patients of Indian origin. In future, the FLT3 protein level may be used to select patients for whom FLT3 inhibitor therapy may be indicated.

Cytokeratin and vimentin expression in breast cancer.

BACKGROUND: The transition from epithelial keratin to mesenchymal vimentin expression marks an important step in the malignant progression of breast cancer. This study analyzed the clinical significance of cytokeratin and vimentin in patients with breast cancer. MATERIALS AND METHODS: Expression of cytokeratin and vimentin was evaluated by immunohistochemistry on paraffin-embedded tissue sections of patients with breast cancer. RESULTS: Loss of cytokeratin was seen in 11% of the patients. A clearer trend towards loss of cytokeratin was observed in patients with stage IV disease and PR negativity. Weak cytokeratin expression was present in patients who developed recurrence or metastatic disease. Loss of cytokeratin was associated with reduced overall survival in univariate and multivariate analysis, gain of vimentin expression was seen in 57% of breast carcinoma patients. It was higher in patients with lymph node positivity, advanced stage, HER2 positivity, and disease recurrence or metastasis. Multivariate survival analysis indicated that gain of vimentin expression was associated with reduced relapse-free survival. CONCLUSION: Loss of cytokeratin and gain of vimentin expression are indicators of biologically aggressive breast carcinoma.