[Prognostic Significance of ERG Gene Rearrangement and Protein Expression in Prostate Cancer].

OBJECTIVES: To investigate gene rearrangement and protein expression of ETS related gene (ERG ) in prostate cancer of Chinese patients and its correlation with clinicopathological characteristics and prognosis. METHODS: This study collected 482 cases of prostatic adenocarcinomas diagnosed by prostate biopsy in West China Hospital of Sichuan University from 2009 to 2014. Fluorescencein situ hybridization (FISH) and immuno-histochemical staining (IHC) were performed to access the ERG rearrangement and protein expression respectively. Relationship between ERG rearrangement and protein expression was assessed by Spearman rank order correlation. The correlations of ERG rearrangement and protein expression with clinicopathological variables and prognosis were further analyzed. RESULTS: ERG rearrangement was detected in 87 (18.0 %) cases, of which 45 (51.7%) was translocation and 42 (48.3%) was deletion. ERG protein expression was detected in 74 (15.4%) cases. Follow-up data was obtained in 368 cases. ERG rearrangement and protein expression had no correlations to age, Gleason score and pre-operation PSA level ( P>0.05), but ERG protein level was decreased in metastatic cases or castration resistant prostate cancer (CRPC) cases ( P<0.05) . Kaplan-Meier curve showed both gene rearrangement and protein expression of ERG had no prognostic significance. CONCLUSIONS: ERG rearrangement, as well as ERG protein expression, could not serve as an independent prognostic biomarker.

SOX9 was involved in TKIs resistance in renal cell carcinoma via Raf/MEK/ERK signaling pathway.

Renal cell carcinoma (RCC) is common genitourinary malignancy in human, 30-40% of patients with RCC would be diagnosed with metastatic RCC (mRCC). Even in the era of targeted therapy, patients with mRCC would inevitably progress due to drug resistance. Herein, exploration of the mechanisms of resistance is noteworthy to study. In the present study, we firstly reported the expression profile of SOX9 in renal carcinoma cells and tissues, and found that its expression was significantly associated with Fuhrman grading. Dual luciferase analysis confirmed that Raf/MEK/ERK pathway could directly be regulated by SOX9, and sequential experiments demonstrated that, renal carcinoma cells could sensitize to Sorafenib/Sunitinib through Raf/MEK/ERK signaling pathway inhibition regulated by SOX9 down-regulation. In a small cases with mRCC treated with Sorafenib/Sunitinib (n=38), comparative analysis showed that patients with SOX9 (-) had much better therapeutic response to TKIs than those with SOX9 (+) (PD: 9.1% vs. 56.2%, P=0.002, DCR: 90.9% vs. 43.8%, P=0.002). Based on these findings, we concluded that, SOX9 was firstly described to be highly expressed in renal cell carcinoma, and its expression was involved in TKIs drug resistance through activation of Raf/MEK/ERK pathway. In vitro, patients with SOX9 (-) was related to better response to TKIs treatment than those with SOX9 (+). SOX9 could be expected to be a promising biomarker predicting TKIs response and even expected to be another novel target in the treatment of mRCC.