Biotransformation of Abiraterone Into Five Characteristic Metabolites by the Rat Gut Microbiota and Liver Microsomes.

It is well known that the role of gut microbiota in drug metabolism, especially in oral difficult absorbable drugs. Understanding the gut microbiota could enable us to understand drugs in new ways. The purpose of the study was to investigate explore the metabolites of the anti-prostate cancer drug Abiraterone by examining gut microbiota metabolism and hepatic metabolism in vitro. In this study, five metabolites (M1, M2, M3, M4 and M5) of Abiraterone were discovered using LC/MSn-IT-TOF. Four isomeric metabolites M1-M4 were found in liver microsome. M5 was found in the intestinal contents of Sprague-Dawley rats with a molecular weight of 388.31. Among them, M4 was found to be Abiraterone N-Oxide by comparison with the standard sample. After further comparing the metabolic behavior of Abiraterone in rat gut microbiota and liver microsomes, we delineated the possible metabolic pathways of Abiraterone. In conclusion, Abiraterone is metabolized specifically in liver microsomes and gut microbiota. This study can provide a theoretical basis for elucidating the metabolic mechanism of Abiraterone and guide its rational application in clinic.

Feasibility of prostatectomy without prostate biopsy in the era of new imaging technology and minimally invasive techniques.

BACKGROUND: Routinely, after receiving prostate specific antigen (PSA) testing and digital rectum examination, patients with suspected prostate cancer are required to undergo prostate biopsy. However, the ability of ultrasound-guided prostate biopsy to detect prostate cancer is limited. Nowadays, a variety of diagnostic methods and more sensitive diagnostic methods, such as multi-parameter prostate magnetic resonance imaging (mpMRI) and prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) can be applied clinically. Furthermore, laparoscopic/robot-assisted prostatectomy is also a safe and effective procedure for the treatment of benign prostatic hyperplasia. So maybe it is time to reconsider the necessary to perform prostate biopsy before radical prostatectomy. AIM: To explore the feasibility of radical prostatectomy without prostate biopsy in the era of new imaging technology and minimally invasive techniques. METHODS: From June 2014 to November 2018, 11 cases of laparoscopic radical prostatectomy without prostate biopsy were performed at the three tertiary medical centers involved in this study. All patients received prostate magnetic resonance imaging and prostate cancer was suspected, including six patients with positive 68Ga-PSMA PET/CT results. Laparoscopic radical prostatectomy and pelvic lymph node dissection were performed for all patients. RESULTS: All surgeries were accomplished successfully. The mean age was 69 ± 7.7 year, the mean body mass index was 24.7 ± 1.6 kg/m2, the range of serum PSA was 4.3 to >1000 ng/mL, and the mean prostate volume was 40.9 ± 18.3 mL. The mean operative time was 96 ± 23.3 min, the mean estimated blood loss was 90 ± 90.9 mL, and the median duration of catheter placement was 14 d. The final pathology confirmed that all specimens were prostate cancer except one case of benign prostatic hyperplasia. No major complications occurred in 90 d postoperatively. CONCLUSION: The current practice of mandating a prostatic biopsy before prostatectomy should be reconsidered in the era of new imaging technology and minimally invasive techniques. Radical prostatectomy could be carried out without the evidence of malignancy. Large-sample randomized controlled trials are definitely required to confirm the feasibility of this new concept.

[Clinical significance of serum levels of endostatin in patients with clear cell renal cell carcinoma].

OBJECTIVE: To assess serum levels of endogenous endostatin in patients with clear cell renal cell carcinoma (CCRCC) and to determine the relationship of these levels to tumor stage, grade. METHODS: From March 2004 to October 2008, preoperative serum were obtained from 138 consecutive patients with CCRCC (73 patients in T1, 39 patients in T2, 20 patients in T3, and 6 patients in T4) and 40 healthy controls. Serum levels of endostatin were measured by sandwich-ELISA. Associations between circulating endostatin levels and clinicopathologic factors and clinical outcome were determined. RESULTS: Endostatin levels did not differ significantly between the patients with CCRCC (93.1 microg/L) and healthy controls (78.9 microg/L, P > 0.05). Serum levels of endostatin were significantly higher in the T2-4 CCRCC patients (107.2 microg/L) than those of the T1 patients (80.4 microg/L, P < 0.01). No significant difference was found in the endostatin levels among the T2-4 patients, or between healthy controls and the T1 patients. The serum endostatin concentration was significantly higher in the metastasis group (118.4 microg/L) than in the no metastasis group (89.5 microg/L, P < 0.05), but there was no significant difference between patients with distant metastasis group (122.0 microg/L) and lymph nodes metastasis (110.0 microg/L, P > 0.05). Patients with G3-4 tumors had significantly higher endostatin levels (111.8 microg/L) than those of patients with G1 (80.4 microg/L) and G2 tumors (86.2 microg/L, P < 0.01), but endostatin levels did not differ significantly between the two groups (P > 0.05). CONCLUSION: Preoperative serum levels of endostatin elevated in patients with CCRCC and associated with higher stage and grade.