Citations

Abstract PARP inhibition can enhance the efficacy of temozolomide and prolong survival in orthotopic glioblastoma (GBM) xenografts. The aim of this study was to evaluate the combination of the PARP inhibitor rucaparib with temozolomide and to correlate pharmacokinetic and pharmacodynamic studies with efficacy in patient-derived GBM xenograft models. The combination of rucaparib with temozolomide was highly effective in vitro in short-term explant cultures derived from GBM12, and, similarly, the combination of rucaparib and temozolomide (dosed for 5 days every 28 days for 3 cycles) significantly prolonged the time to tumor regrowth by 40% in heterotopic xenografts. In contrast, the addition of rucaparib had no impact on the efficacy of temozolomide in GBM12 or GBM39 orthotopic models. Using Madin-Darby canine kidney (MDCK) II cells stably expressing murine BCRP1 or human MDR1, cell accumulation studies demonstrated that rucaparib is transported by both transporters. Consistent with the influence of these efflux pumps on central nervous system drug distribution, Mdr1a/b−/−Bcrp1−/− knockout mice had a significantly higher brain to plasma ratio for rucaparib (1.61 ± 0.25) than wild-type mice (0.11 ± 0.08). A pharmacokinetic and pharmacodynamic evaluation after a single dose confirmed limited accumulation of rucaparib in the brain is associated with substantial residual PARP enzymatic activity. Similarly, matrix-assisted laser desorption/ionization mass spectrometric imaging demonstrated significantly enhanced accumulation of drug in flank tumor compared with normal brain or orthotopic tumors. Collectively, these results suggest that limited drug delivery into brain tumors may significantly limit the efficacy of rucaparib combined with temozolomide in GBM. Mol Cancer Ther; 14(12); 2735–43. ©2015 AACR.

An extracellular stable micelle with a folate conjugated surface, a crosslinked core and pH-sensitive hydrolysable bonds was developed for cancer targeted drug delivery.

Extracellular RNAs (exRNAs) have been identified in all tested biofluids and have been associated with a variety of extracellular vesicles, ribonucleoprotein complexes and lipoprotein complexes. Much of the interest in exRNAs lies in the fact that they may serve as signalling molecules between cells, their potential to serve as biomarkers for prediction and diagnosis of disease and the possibility that exRNAs or the extracellular particles that carry them might be used for therapeutic purposes. Among the most significant bottlenecks to progress in this field is the lack of robust and standardized methods for collection and processing of biofluids, separation of different types of exRNA‐containing particles and isolation and analysis of exRNAs. The Sample and Assay Standards Working Group of the Extracellular RNA Communication Consortium is a group of laboratories funded by the U.S. National Institutes of Health to develop such methods. In our first joint endeavour, we held a series of conference calls and in‐person meetings to survey the methods used among our members, placed them in the context of the current literature and used our findings to identify areas in which the identification of robust methodologies would promote rapid advancements in the exRNA field.

Abstract Monoclonal antibodies that target the programmed death-1 (PD-1)–programmed death ligand-1 (PD-L1) axis have antitumor activity against multiple cancers. The presence of sarcomatoid differentiation in renal cell carcinoma (RCC) is associated with resistance to targeted therapy and poor responses to IL2 immunotherapy. Given the aggressive nature of RCC with sarcomatoid differentiation and the exclusion of sarcomatoid histology from metastatic RCC clinical trials, less is understood regarding selection of therapies. Here, we characterized the PD-1/PD-L1 axis in RCC with sarcomatoid differentiation. We directly compared two PD-L1 antibodies and found concordance of PD-L1 positivity in 89% of tested RCCs with sarcomatoid differentiation. Coexpression of PD-L1 on neoplastic cells and the presence of PD-1–positive tumor-infiltrating lymphocytes were identified in 50% (13 of 26) of RCCs with sarcomatoid differentiation. In contrast, only 1 of 29 clear cell RCCs (3%) had concurrent expression of PD-L1 and PD-1 (P = 0.002). Our study suggests that RCC with sarcomatoid differentiation may express PD-1/PD-L1 at a higher percentage than RCC without sarcomatoid differentiation, and patients with these tumors may be good candidates for treatment with anti–PD-1/PD-L1 therapies. Cancer Immunol Res; 3(12); 1303–7. ©2015 AACR.

Abstract Background Gastrointestinal infections are risk factors for irritable bowel syndrome ( IBS ) and functional dyspepsia ( FD ). We investigated whether non‐enteric infections and antibiotic exposure are also associated with the development of functional gastrointestinal disorders ( FGID s). Methods In a nested case–control study, random samples of Olmsted County, MN , were mailed valid self‐report questionnaires from 1988 through 1994, and then follow‐up questionnaires from 1995 through 2003. Survey responders who did not report any FGID symptoms at baseline, but then reported such symptoms in at least one subsequent survey, were classified as new‐onset cases. Age‐matched controls were individuals who did not have symptoms at either the initial or subsequent surveys. Key Results The overall response rate was 78% to the initial survey and 52% to the follow‐up survey. Based on the responses, 316 participants had a new onset of an FGID (43 IBS constipation, 95 IBS diarrhea, 25 IBS mixed, and 153 other FGID s, including FD ) and 250 did not (controls). Around 76% (241/316) of cases reported a non‐enteric infection vs 66% (166/250) of the controls. The frequency of enteric infections was similar between the two groups. Of the new FGID cases, 83% had a non‐enteric infection that was treated with antibiotic. In a logistic regression model, treatment with antibiotics for a non‐gastrointestinal infection was associated with the development of an FGID (odds ratio = 1.90; 95% CI : 1.21–2.98; p = 0.005), after adjusting for age and sex. Conclusions & Inferences Based on a case–control study, treatment of a non‐gastrointestinal infection with antibiotics appears to be a risk factor for development of an FGID .