RELATIONSHIP OF ErbB-2 WITH EGFR AND ErbB-3 IN THE CLEAR CELL RENAL CELL CARCINOMA (ccRCC)

MARIA ALICIA CORTÉS; LUCIA ROTT ; JUAN JOSE DIAZ ; AYELEN HERMOSO ; SOFIA BELEN MEZA ; HECTOR MARCELO MARIN ; ROSALIA I. CORDO RUSSO; ROSANA M. GEROMETTA ; PATRICIA V. ELIZALDE

Congreso; ANNUAL MEETING OF BIOSCIENCE SOCIETIES 2020; 2020

The most common subtype of renal cancer is clear cell renal cell carcinoma (ccRCC), which accounts for 80-90% of all renal cancer cases. Currently kinase inhibitor therapy is used in advanced ccRCC, because the ccRCC is resistant to chemo- and radiotherapy. And there is no biomarker to guide therapy. While among the EGF receptors in the ccRCC, EGFR and ErbB-3 are expressed, ErbB-2 presence is not clear. In this context, we explored the expression and localization of ErbB-2 and its relationship with EGFR and ErbB-3. The technique used was immunohistochemistry. We selected 72 paraffin- embedded tissue samples from a cohort of archived ccCCR from the files of the Histolopathology service in Vidal Hospital, Corrientes from 2005 to 2019. Our results show that the membrane expression of ErbB-2 (MErbB-2) is 40% (29/73). However, it is not related to the stage (Chi-square test ns, Stage I and II vs III and IV). We explored the nuclear expression of ErbB-2 (NErbB-2) and 67% resulted positive (1+ 33%, 2+ 28%, 3+ 8%). We show that nuclear ErbB2 (NErbB-2) is correlated with high Fuhrman Nuclear Grade (FNG) Chi-square test *P=0.017 FNG 1 vs 2, ***P=0.0009 FNG 1 vs 3/4. Nuclear EGFR and ErbB-3 expression and the correlation with nuclear ErbB-2 were also explored. Our results show that, nuclear expression of EGFR (NEGFR) is 1+ (11%), 2+ (38%), 3+ (30%) and nuclear expression of ErbB-3 is 1+ (9%), 2+ (14%), 3+ (40%). The correlation of Pearson was positive for both NEGFR (**P=0.02) and NErbB-3 (**P=0.07) vs NErbB-2. Our findings showed that ErbB-2 is implicated in the carcinogenesis renal. It is very important to locate ErbB-2 because in the clear cell renal cell carcinoma nuclear ErbB-2 is associated with high FNG. The molecular mechanism of ErbB-2 nuclear location seems to be related to ErbB-2/EGFR and ErbB-2/ErbB-3 in renal cell carcinoma.