TGF-ß1 expression in chromophobe renal cell carcinoma and renal oncocytoma.

Distinguishing renal oncocytoma (RO) from the eosinophilic variant of chromophobe renal cell carcinoma (ChRCC) under the light microscope is a common diagnostic problem. Our recent research has shown significant difference between the presence of tumor fibrous capsule in ChRCCs and ROs. Transforming growth factor beta 1 (TGF-ß1) is a potent cytokine involved in regulating a number of cellular processes. Two main purposes of this research were to investigate whether the TGF-ß1 staining could be related to the presence of tumor fibrous capsule and if it could be used in the differential diagnosis between ChRCC and RO. We investigated 34 cases: 16 ChRCCs (8 eosinophilic and 8 classic) and 18 ROs. All available slides of each tumor, routinely stained with hematoxylin and eosin (H&E) were first analyzed to note the presence of tumor fibrous capsule. One paraffin embedded tissue block matching the representative H&E slide was selected for the immunohistochemical analysis. TGF-ß1 expression was analyzed semiquantitatively in the tumor tissue, the tumor fibrous capsule, if present and the peritumoral renal parenchyma. Intensity of TGF-ß1 expression was weaker in ChRCCs than the one observed in ROs (P<0.05). The type of reaction in ChRCCs was predominantly membranous unlike in ROs, which exhibited a predominantly cytoplasmic reaction (P<0.05). Moreover, none of the ROs showed membranous type of reaction for TGF-ß1. In the group of ChRCCs, tumors with capsule had statistically significant higher quantity of TGF-ß1 expression in tumor tissue and in peritumoral renal parenchyma compared to the tumors without capsule (P<0.05). Our results showed different types of TGF-ß1 expression in ChRCCs and ROs: ChRCCs had predominantly membranous type of reaction, and ROs predominantly cytoplasmic. Furthermore, ChRCCs with capsule had statistically significant higher quantity of TGF-ß1 expression in tumor tissue and in peritumoral renal parenchyma compared to the tumors without capsule. Based on these findings we can speculate that it could be possible that TGF-ß1 plays a role in the formation of fibrous capsule in ChRCCs.

Prognostic value of connexin43 expression in patients with clinically localized prostate cancer.

Connexins (Cxs) are a family of transmembrane proteins that build cell-to-cell channels in gap junctions. Gap junctions composed of Cxs have an essential role in intercellular communication, adhesion and cell differentiation. Several studies investigated the role of connexin43 (Cx43) in different carcinomas; however, none investigated its prognostic role in prostate cancer. Cx43 expression and relationship with established prognostic features were assessed in a cohort of 102 patients treated with radical prostatectomy for clinically localized prostate adenocarcinoma. Cx43 expression in prostate cancer was significantly associated with established features indicative of worse prognosis, such as follow-up time (P < 0.001) and preoperative PSA (P < 0.007). Patients with lower Cx43 expressions in tumours have shorter follow-up time, which indicated shorter disease-free survival and higher preoperative PSA values. Furthermore, tumours with positive surgical margins (P < 0.001) showed significantly lower Cx43 expression compared with tumours without this feature. In univariate (P < 0.001) and multivariate (P = 0.014) analyses, decreased Cx43 expression was found to be a significant predictor of biochemical recurrence free-survival. Study results show the association of decreased Cx43 expression with prostate cancer progression. Moreover, Cx43 could serve as an additional prognostic marker and used together with traditional prognostic markers might help in further stratifying the risk of disease progression in patients with prostate cancer.

Expression and prognostic role of syndecan-2 in prostate cancer.

Syndecans are a four-member family of transmembrane heparan sulphate proteoglycans that have different functions in cell signalling, adhesion, cytoskeleton organization, migration, proliferation, and angiogenesis. Several studies investigated the role of syndecan-2 (SDC2) in different carcinomas; however, only one being focused on SDC2 in prostate cancer. SDC2 expression and relationship with established prognostic features were assessed in a cohort of 86 patients treated with radical prostatectomy for clinically localized prostate adenocarcinoma. SDC2 expression was present in the majority of prostate cancers and absent in only 11.6% of cases. SDC2 expression was also recorded in cells of prostatic intraepithelial neoplasia, whereas normal prostatic epithelial tissue and stroma did not express SDC2. SDC2 overexpression in prostate cancer was significantly associated with established features indicative of worse prognosis such as higher preoperative PSA (P=0.011), higher Gleason score (P<0.001), positive surgical margins (P<0.003), and extraprostatic extension of disease (P<0.003). Moreover, expression of SDC2 was also associated with biochemical disease progression on univariate analysis (P<0.001). Study results supported the potential role of SDC2 in prostatic carcinogenesis and cancer progression. Moreover, SDC2 could serve as an additional prognostic marker that might help in further stratifying the risk of disease progression in patients with prostate cancer.