Expression of insulin-like factor 3 protein in the rat testis during fetal and postnatal development and in relation to cryptorchidism induced by in utero exposure to di (n-Butyl) phthalate.

Cryptorchidism is a common reproductive abnormality, possibly resulting from abnormal hormone production/action by the fetal testis. Insulin-like factor 3 (Insl3) is thought to be involved in gubernaculum development and transabdominal testicular descent, but its importance is unclear, due partly to lack of suitable Insl3 antibodies. We generated (by genetic immunization) and validated a novel antirat Insl3 antibody, which we used to characterize immunoexpression of Insl3 in rat Leydig cells (LCs) from fetal life until adulthood and its relationship to cryptorchidism. Immunoexpression was strong on embryonic day (E) 17.5 and E19.5 and from 35 d of age onward but weak from E21.5 until puberty. Because in utero exposure to di (n-butyl) phthalate (DBP) induces cryptorchidism and suppresses Insl3 gene expression, we investigated Insl3 protein expression in fetal and adult rats exposed to 500 mg/kg.d DBP from E13.5 to E21.5. Expression on E17.5 and E19.5 decreased dramatically after DBP exposure, but there was no consistent correlation between this suppression and abnormal testis position. We also compared expression of Insl3 and P450 side-chain cleavage enzyme in fetal testes from rats exposed in utero to DBP or flutamide (50 mg/kg.d). DBP treatment suppressed expression of both P450 side-chain cleavage enzyme and Insl3 at E19.5, but flutamide exposure had no effect on either protein, demonstrating that Insl3 expression in fetal rat LCs is not androgen regulated. In adult rats, Insl3 expression was suppressed in 80% of cryptorchid and 50% of scrotal testes from rats exposed to DBP, suggesting that prenatal DBP exposure also leads to maldevelopment/malfunction of the adult LC population in some animals.

Final overall survival analysis of a phase II trial evaluating vinorelbine and lapatinib in women with ErbB2 overexpressing metastatic breast cancer.

Lapatinib plus capecitabine (lap+cap) is approved as treatment for patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC), who have progressed on prior trastuzumab in the metastatic setting. We previously reported progression-free survival (PFS), overall survival (OS) and safety results from this open-label, multicentre, phase II study (VITAL; NCT01013740) conducted in women with HER2 positive MBC, to evaluate the efficacy and safety of lap plus vinorelbine (lap+vin), an important chemotherapy option for MBC, compared with lap+cap. In total, 112 patients were randomised 2:1 to treatment with lap+vin (N = 75) or lap+cap (N = 37). Results showed that the median PFS (primary endpoint) and OS (secondary endpoint) post-randomisation were comparable between treatment arms, with no new safety signals detected. Here, we assessed the final OS in this study at 40 months post-randomisation. At the time of final analyses, 24 (32%) patients were ongoing in the lap+vin arm, compared with 14 (38%) patients in the lap+cap arm (92% in both arms had discontinued treatment). Median OS in the lap+vin arm was 23.3 months (95% confidence intervals [CI]: 18.5, 31.1), compared with 20.3 months (95% CI: 16.4, 31.8) in the lap+cap arm. The median follow-up in the lap+vin arm was 18.86 months (95% CI: 10.68, 26.02), compared with 19.38 (95% CI: 25.56) months in the lap+cap arm. Similar rates of death (56-57%) were observed in both arms. The final OS was consistent with the previously reported data and suggest that lap+vin offers an effective treatment option for women with HER2-positive MBC.