Modified early intensive and treat-and-extend regimen of anti-vascular endothelial growth factor for diabetic macular edema in Taiwan

Given the rising prevalence of patients with diabetes and increasing treatment burden for patients with vision-threatening diabetic macular edema (DME), we aimed to explore the efficacy of modified early intensive and treat-and-extend regimen of anti-vascular endothelial growth factor (VEGF) therapy under the Taiwan National Insurance Bureau reimbursement policy. We obtained data on 69 eyes treated with initial 4-monthly intravitreal injections of aflibercept or ranibizumab, plus individualized treat-and-extend regimen. At 12 months, the mean (SD) change in LogMAR best corrected visual acuity from baseline was - 0.28 (0.31) in all eyes, while that in the aflibercept and ranibizumab groups were - 0.30 (0.34) and - 0.25 (0.28), respectively. Central retinal thickness decreased by 137.2 (122.4) in all eyes, 138.1 (134.2) in the aflibercept group, and 136.2 (110.9) in the ranibizumab group. Additionally, the aflibercept group had a lower mean number of injections than the ranibizumab group (8.5 vs. 8.7). The last extended dosing interval of > 12 weeks was 31.0% and 16.7% of the eyes in the aflibercept and ranibizumab groups, respectively. The modified anti-VEGF regimens effectively managed DME in terms of functional and anatomical outcomes, and efficiently reduced the healthcare burden by reducing the number of injections and extending treatment intervals within 12 months.

Cerebellar α6 -subunit-containing GABAA receptors: a novel therapeutic target for disrupted prepulse inhibition in neuropsychiatric disorders

BACKGROUND AND PURPOSE

The pathophysiological role of α₆ -subunit-containing GABA_A receptors, which are mainly expressed in cerebellar granule cells, remains unclear. Recently, we demonstrated that hispidulin, a flavonoid isolated from a local herb that remitted a patient's intractable motor tics, attenuated methamphetamine-induced hyperlocomotion in mice as a positive allosteric modulator (PAM) of cerebellar α₆ GABA_A receptors. Here, using hispidulin and a selective α₆ GABA_A receptor PAM, the pyrazoloquinolinone Compound 6, we revealed an unprecedented role of cerebellar α₆ GABA_A receptors in disrupted prepulse inhibition of the startle response (PPI), which reflects sensorimotor gating deficits manifested in several neuropsychiatric disorders.

EXPERIMENTAL APPROACH

PPI disruptions were induced by methamphetamine and NMDA receptor antagonists in mice. Effects of the tested compounds were measured in Xenopus oocytes expressing recombinant α₆ β₃ γ_2S GABA_A receptors.

KEY RESULTS

Hispidulin given i.p. or by bilateral intracerebellar (i.cb.) injection rescued PPI disruptions induced by methamphetamine, ketamine, MK-801 and phencyclidine. Intracerebellar effects of hispidulin were mimicked by Ro15-4513 and loreclezole (two α₆ GABA_A receptor PAMs), but not by diazepam (an α₆ GABA_A receptor-inactive benzodiazepine) and were antagonized by furosemide (i.cb.), an α₆ GABA_A receptor antagonist. Importantly, Compound 6 (i.p.) also rescued methamphetamine-induced PPI disruption, an effect prevented by furosemide (i.cb.). Both hispidulin and Compound 6 potentiated α₆ β₃ γ_2S GABA_A receptor-mediated GABA currents.

CONCLUSIONS AND IMPLICATIONS

Positive allosteric modulation of cerebellar α₆ GABA_A receptors rescued disrupted PPI by attenuating granule cell activity. α₆ GABA_A receptor-selective PAMs are potential medicines for treating sensorimotor gating deficits in neuropsychiatric disorders. A mechanistic hypothesis is based on evidence for cerebellar contributions to cognitive functioning including sensorimotor gating.

CHSY1 promotes aggressive phenotypes of hepatocellular carcinoma cells via activation of the hedgehog signaling pathway

Abnormal expression of chondroitin sulfate has been found in many types of cancer, while its biological functions in hepatocellular carcinoma (HCC) progression remain uninvestigated. Here, we report that chondroitin sulfate synthase 1 (CHSY1), the enzyme that mediates the polymerization step of chondroitin sulfate, is a critical mediator of malignant character in HCC that acts via modulating the activity of the hedgehog signaling. CHSY1 was up-regulated frequently in HCC where these events were associated with worse histologic grade and poor survival. Enforced expression of CHSY1 was sufficient to enhance cell growth, migration, invasion, and epithelial-mesenchymal transition, whereas silencing of CHSY1 suppressed these malignant phenotypes. Mechanistic investigations revealed that the increase of cell surface chondroitin sulfate by CHSY1 promoted sonic hedgehog binding and signaling. Inhibiting hedgehog pathway with vismodegib decreased CHSY1-induced migration, invasion, and lung metastasis of HCC cells, establishing the critical role of hedgehog signaling in mediating the effects of CHSY1 expression. Together, our results indicate that CHSY1 overexpression in HCC contributes to the malignant behaviors in cancer cells, we provide novel insights into the significance of chondroitin sulfate in hedgehog signaling and HCC pathogenesis.

Redistribution of Cav2.1 channels and calcium ions in nerve terminals following end-to-side neurorrhaphy: ionic imaging analysis by TOF-SIMS

The P/Q-type voltage-dependent calcium channel (Cav2.1) in the presynaptic membranes of motor nerve terminals plays an important role in regulating Ca²⁺ transport, resulting in transmitter release within the nervous system. The recovery of Ca²⁺-dependent signal transduction on motor end plates (MEPs) and innervated muscle may directly reflect nerve regeneration following peripheral nerve injury. Although the functional significance of calcium channels and the levels of Ca²⁺ signalling in nerve regeneration are well documented, little is known about calcium channel expression and its relation with the dynamic Ca²⁺ ion distribution at regenerating MEPs. In the present study, end-to-side neurorrhaphy (ESN) was performed as an in vivo model of peripheral nerve injury. The distribution of Ca²⁺ at regenerating MEPs following ESN was first detected by time-of-flight secondary ion mass spectrometry, and the specific localization and expression of Cav2.1 channels were examined by confocal microscopy and western blotting. Compared with other fundamental ions, such as Na⁺ and K⁺, dramatic changes in the Ca²⁺ distribution were detected along with the progression of MEP regeneration. The re-establishment of Ca²⁺ distribution and intensity were correlated with the functional recovery of muscle in ESN rats. Furthermore, the re-clustering of Cav2.1 channels after ESN at the nerve terminals corresponded with changes in the Ca²⁺ distribution. These results indicated that renewal of the Cav2.1 distribution within the presynaptic nerve terminals may be necessary for initiating a proper Ca²⁺ influx and shortening the latency of muscle contraction during nerve regeneration.

A phase II study of gemcitabine and cisplatin plus sorafenib in patients with advanced biliary adenocarcinomas

Background:

This study evaluated the addition of sorafenib to gemcitabine and cisplatin in biliary adenocarcinoma first-line therapy.

Methods:

Patients with advanced biliary adenocarcinomas received gemcitabine 1000 mg m⁻² and cisplatin 25 mg m⁻² on a 2 weeks on/1 week off cycle and sorafenib 400 mg twice daily. After the initial 16 patients were enrolled, the chemotherapy doses were amended in view of grade 3 and 4 hand–foot skin reaction and haematologic toxicity. Subsequently, 21 patients received gemcitabine 800 mg m⁻², cisplatin 20 mg m⁻² and sorafenib 400 mg. The primary end point was an improvement in 6-month progression-free survival (PFS6) from historical 57–77% (90% power, type I error of 10%). Pretreatment pERK, evaluated by immunostaining, was correlated with clinical outcome.

Results:

A total of 39 patients were accrued. The most common grade 3–4 toxicities noted in >10% of patients were fatigue, elevated liver function tests and haematologic toxicities including thromboemboli, hyponatraemia and hypophosphataemia. Six-month progression-free survival was 51% (95% confidence interval (CI) 34–66%). Median PFS and overall survival were 6.5 (95% CI: 3.5–8.3) and 14.4 months (95% CI: 11.6–19.2 months), respectively. No correlation was observed between pERK and outcomes.

Conclusion:

The addition of sorafenib to gemcitabine and cisplatin in biliary adenocarcinomas did not improve efficacy over historical data, and toxicity was increased.

Hepatic arterial nodal metastases in pancreatic cancer: is this the node of importance?

BACKGROUND

The hepatic artery lymph node (HALN) is frequently sampled during pancreaticoduodenectomy (PD). Data suggest that survival in the setting of HALN metastases is similar to that of stage IV pancreatic ductal adenocarcinoma (PDAC). The objectives of this study were to describe the prognostic significance of HALN metastases and to assess the predictive performance of HALN compared to peripancreatic lymph node status.

METHODS

Patients undergoing PD for PDAC from January 2000-October 2010 were identified from a prospectively maintained database. Patients were included if during PD the HALN was submitted for pathologic evaluation. Patients were excluded if margins were macroscopically positive, if pathology was found to be consistent with a diagnosis other than PDAC. Overall (OS) and disease-free survival (DFS) were estimated by Kaplan-Meier methods.

RESULTS

Of the 671 patients who underwent PD for PDAC, HALN status was analyzed for 147 patients. HALN was positive in 23 patients (16 %), 38 were peripancreatic lymph node (PPLN) and HALN negative, and 86 were PPLN+/HALN-. Median follow-up for survivors was 10 months. In a multivariable model, lymph node status and tumor differentiation predicted OS and DFS. Hazard of death and relapse/death were highest among the HALN+ patients (hazard ratio [HR] 2.94; p = 0.017 and HR 2.66; p = 0.011, respectively). Kaplan-Meier analysis revealed significant differences in OS (p = 0.017) and DFS (p = 0.013) based on lymph node status.

CONCLUSIONS

OS and DFS are significantly reduced in patients with a positive HALN. Differentiation and lymph node status were predictors of OS and DFS. In the multivariate models, differentiation and lymph node status remain independent predictors of OS and DFS.