A phase II study of sunitinib in recurrent and/or metastatic adenoid cystic carcinoma (ACC) of the salivary glands: current progress and challenges in evaluating molecularly targeted agents in ACC

BACKGROUND

Vascular endothelial growth factor (VEGF) and c-kit are highly expressed in adenoid cystic carcinoma (ACC) and associated with biologic aggressiveness. This study aimed to assess the antitumor activity of sunitinib, a multi-targeted inhibitor of vascular endothelial growth factor receptor, c-kit, platelet-derived growth factor receptor, ret proto-oncogene (RET) and FMS-like tyrosine kinase 3 (FLT3), in ACC of the salivary gland.

PATIENTS AND METHODS

Patients with progressive, recurrent and/or metastatic ACC were treated with sunitinib 37.5 mg daily in this single-arm, two-stage phase II trial. Response was assessed every 8 weeks.

RESULTS

Fourteen patients were enrolled on to the study. Among 13 assessable patients, there were no objective responses, 11 patients had stable disease (SD), 8 patients had SD ≥ 6 months and 2 patients had progressive disease as best response. Median time to progression was 7.2 months. Median overall survival was 18.7 months. Toxic effects occurring in at least 50% of patients included fatigue, oral mucositis and hypophosphatemia usually of mild to moderate severity.

CONCLUSIONS

Although no responses were observed, sunitinib was well tolerated, with prolonged tumor stabilization of ≥ 6 months in 62% of assessable patients. The lack of responses is comparable with other trials of molecularly targeted agents in ACC and highlights the need for novel strategies in phase II clinical trial design.

Effect of conventional and resin-modified glass-ionomer liner on dentin adhesive interface of Class I cavity walls after thermocycling

OBJECTIVE

The aim of this in vitro study was to analyze the effect of glass-ionomer cement as a liner on the dentin/resin adhesive interface of lateral walls of occlusal restorations after thermocycling.

MATERIALS AND METHODS

Occlusal cavities were prepared in 60 human molars, divided into six groups: no liner (1 and 4); glass-ionomer cement (GIC, Ketac Molar Easymix, 3M ESPE) (2 and 5); and resin-modified glass-ionomer cement (RMGIC, Vitrebond, 3M ESPE) (3 and 6). Resin composite (Filtek Z250, 3M ESPE) was placed after application of an adhesive system (Adper Single Bond 2, 3M ESPE) that was mixed with a fluorescent reagent (Rhodamine B) to allow confocal microscopy analysis. Specimens of groups 4, 5 and 6 were thermocycled (5°C-55°C) with a dwell time of 30 seconds for 5000 cycles. After this period, teeth were sectioned in approximately 0.8-mm slices. One slice of each tooth was randomly selected for confocal microscopy analysis. The other slices were sectioned into 0.8 mm × 0.8 mm beams, which were submitted to microtensile testing (MPa). Data were analyzed using two-way ANOVA and Tukey test (p<0.05).

RESULTS

There was no detectedstatistical difference on bond strength among groups (α<0.05). Confocal microscopy analysis showed a higher mean gap size in group 4 (12.5 μm) and a higher percentage of marginal gaps in the thermocycled groups. The RMGIC liner groups showed the lowest percentage of marginal gaps.

CONCLUSIONS

Lining with RMGIC resulted in less gap formation at the dentin/resin adhesive interface after artificial aging. RMGIC or GIC liners did not alter the microtensile bond strength of adhesive system/resin composite to dentin on the lateral walls of Class I restorations.

Phase I trial of pemetrexed in combination with cetuximab and concurrent radiotherapy in patients with head and neck cancer

BACKGROUND

We studied the combination of pemetrexed, a multi-targeted antifolate, and cetuximab, an mAb against the epidermal growth factor receptor, with radiotherapy in poor prognosis head and neck cancer.

PATIENTS AND METHODS

Patients received pemetrexed on days 1, 22, and 43 on a dose-escalation scheme with starting level (0) 350 mg/m(2) (level -1, 200 mg/m(2); level +1, 500 mg/m(2)) with concurrent radiotherapy (2 Gy/day) and cetuximab in two separate cohorts, not previously irradiated (A) and previously irradiated (B), who received 70 and 60-66 Gy, respectively. Genetic polymorphisms of thymidylate synthase and methylenetetrahydrofolate reductase were evaluated.

RESULTS

Thirty-two patients were enrolled. The maximum tolerated dose of pemetrexed was 500 mg/m(2) in cohort A and 350 mg/m(2) in cohort B. Prophylactic antibiotics were required. In cohort A, two dose-limiting toxicities (DLTs) occurred (febrile neutropenia), one each at levels 0 and +1. In cohort B, two DLTs occurred at level +1 (febrile neutropenia; death from perforated duodenal ulcer and sepsis). Grade 3 mucositis was common. No association of gene polymorphisms with toxicity or efficacy was evident.

CONCLUSION

The addition of pemetrexed 500 mg/m(2) to cetuximab and radiotherapy is recommended for further study in not previously irradiated patients.

Modelling the transmission dynamics of meticillin-resistant Staphylococcus aureus in Beijing Tongren hospital

Semi-professional volunteers work in many tertiary care hospitals in China as healthcare assistants. Proper infection control measures are needed to reduce nosocomial transmission involving volunteers. A compartmental model was constructed to describe the transmission characteristics of meticillin-resistant Staphylococcus aureus (MRSA) in the emergency ward (EW) and respiratory intensive care unit (RICU) for volunteers in Beijing Tongren Hospital, Beijing, China. The model consists of components describing uncolonized and colonized patients, uncontaminated and contaminated healthcare workers (HCWs), and uncontaminated and contaminated volunteers. The basic reproduction number (R(0)) was calculated, and the dependence of R(0) on various model parameters was analysed. Moreover, simulations of the model were performed for comparision with the reported data on the numbers of colonized patients in the EW and RICU from 3 March 2009 to 28 February 2010, respectively. Sensitivity analysis of R(0) showed that increasing handwashing compliance among HCWs and volunteers would reduce the risk of transmission dramatically. As volunteers care for patients on a one-to-one basis, this study showed that the number of MRSA-positive patients would increase if volunteers were replaced by HCWs. Therefore, in addition to improving hand hygiene among HCWs, the employment of properly trained volunteers is an attractive alternative to decrease MRSA and other multi-drug resistant bacteria infections in the hospital setting.

Toxicity of melamine and cyanuric acid in broilers and residues in tissues

The purpose of this study was to characterize the toxicity potential of melamine (MEL), cyanuric acid (CYA), and a combination of MEL and CYA in broilers. A total of 720 commercial 1-day-old COBB 500 male broilers were randomly allotted into 6 groups with 6 replicates each and 20 broilers in each replicate. The dietary treatments were as follows: group I was the control group, group II included 10 mg/kg MEL and 3.3 mg/kg CYA, group III included 30 mg/kg MEL and 10 mg/kg CYA, group IV included 100 mg/kg MEL and 33.3 mg/kg CYA, group V included 100 mg/kg MEL, and group VI included 33.3 mg/kg CYA. The trial lasted for 42 days. CYA alone and the combination of MEL and CYA had adverse effects on the performance, but MEL alone had no effects on the performance. On day 21, the uric acid (UA) content of group IV was increased in serum ( p < 0.05); on day 42, the serum aspartate aminotransferase (AST) activity and the level of tumor necrosis factor (TNF)-α and interleukin (IL)-8 increased in group IV ( p < 0.05); 100 mg/kg MEL alone increased the level of TNF-α and the rate of renal apoptosis ( p < 0.05); and 33.3 mg/kg CYA alone increased the level of IL-8 and the rate of renal apoptosis ( p < 0.05). The livers contained MEL concentrations of 17–125 μg/kg wet weight and CYA concentrations of 28–73 μg/kg, and the muscle contained MEL concentrations of 14–105 μg/kg wet weight. It was indicated that MEL alone, CYA alone, and a combination of MEL and CYA inhibit the growth and damage the kidney and liver.

Heme oxygenase-1 expression and its significance for acute rejection following kidney transplantation in rats

OBJECTIVE

To analyze rejection and antiapoptotic effects of heme oxygenase-1 (HO-1) in kidney transplantations, to investigate the protective effects of endogenous HO-1 induced by hemin on acute rat kidney allograft rejection.

METHODS

We selected 27 Brown-Norway rats and 27 male Lewis rats as donors and recipients, respectively, randomly dividing them into three groups: kidney transplantation alone, hemin treatment group, and cyclosporine (CsA) group (n = 18). Six recipient rats were harvested on the first, fifth, or seventh days after operation among each group to examine histopathologic changes in renal tissue, HO-1 protein expression, and acute rejection as well as to measure serum creatinine values.

RESULTS

HO-1 expression in both the kidney transplantation model group and the hemin-induced groups were higher compared with the CsA group (P < .05-.01). The expression increased with the aggravation of rejection; the expression in the CsA group also increased after transplantation but was obviously lower than that of the hemin-induced group (P < .01). The rejection process was relatively mild as indenset by histopathologic examination. The serum creatinine levels among the hemin-induced group were lower compared to the kidney transplantation control group (P < .05), but higher compared to the CsA group (P < .05).

CONCLUSION

HO-1 provided protection of allografts against rejection in rats, but such effects were poorer than those achieved using potent immunosuppressive agents like CsA.

MicroRNA-mediated breast cancer metastasis: from primary site to distant organs

The recent upsurge of interest in microRNA (miRNA) is partly attributed to the discovery of the novel roles of miRNAs in many physiological and pathological processes, including tumor development. Research on breast cancer metastasis has also focused on the concept of miRNA, which can act either as promoters or as suppressors of metastases. This review will focus on a series of recent studies that demonstrate the involvement of miRNAs in breast cancer metastasis and will briefly describe various pathways of miRNA-regulated metastasis. Finally, future prospects will be discussed for the potential role of miRNAs as predictive markers and therapeutic agents for patients with breast cancer metastases.