TUMOR EFFECT ON ITS ADIPOSE MICROENVIRONMENT IN HUMAN BREAST CANCER ? AN IMMUNOHISTOCHEMICAL STUDY

FLETCHER SJ; URSINO A; GUTIÉRREZ A; CARÓN RW; CROSBIE ML; FRASCAROLLI MC; DRESZMAN R; PISTONE-CREYDT, VIRGINIA; FLETCHER S, SACCA PA, TESONE AJ, BRUZZONE A, LÜTHY IA, GONZALEZ EG, CALVO JC, PISTONE CREYDT V; SANTISO N; AMATO AR; CALVO JC

Mendoza

Congreso; XXXIV Reunión Anual de la Sociedad de Biología de Cuyo; 2016

Tumorstroma is one of the emerging topics of interest in cancer research. In breastcancer, tumor epithelial cells interact dynamically with different stromalcells. This interaction has been shown to be crucial for tumor progression anddissemination. Adipose tissue is the main component of the breast stroma.Therefore, in this study we aim to identify the effect that breast tumors haveon their adipose microenvironment. For this we collected samples of humanbreast adipose tissue from tumor breasts (hATT) of patients with cancer andfrom normal breasts (hATN) of healthy women. The explants were fixed withformaldehyde 4%, embedded in paraffin and sliced for immunohistochemicalanalysis. We found that adiponectin (one of the major adipokines and withanti-tumorigenic effects) expression was significantly increased in hATN vshATT (p<0.05). Interestingly, adiponectin receptor Adipo R1 showed asignificantly increased expression in hATT vs hATN (p<0.05). We didn´t finda difference in the expression of leptin (the other major adipokine) and of itsreceptor ObR. Furthermore, caveolin 1 (principal component of caveolaemembranes in adipocytes and involved in signal transduction) was significantlyincreased in hATT compared to hATN (p<0.01). When we studied thedifferentiation state of adipocytes we found that expression of perilipin A (markerfor mature differentiated adipocyte) was decreased (p=0,055) and of CD44(marker for adipose stem cells) was significantly increased in hATT vs hATN(p<0.05). In conclusion, the changes observed in the adiposemicroenvironment could be favoring tumor progression and therefore, the tumorstroma should be taken into consideration when dealing with a malignancy.