Biphasic modulation by mGlu5 receptors of TRPV1-mediated intracellular calcium elevation in sensory neurons contributes to heat sensitivity

BACKGROUND AND PURPOSE

Elevation of glutamate, an excitatory amino acid, during inflammation and injury plays a crucial role in the reception and transmission of sensory information via ionotropic and metabotropic receptors. This study aimed to investigate the mechanisms underlying the biphasic effects of metabotropic glutamate mGlu5 receptor activation on responses to noxious heat.

EXPERIMENTAL APPROACH

We assessed the effects of intraplantar quisqualate, a non-selective glutamate receptor agonist, on heat and mechanical pain behaviours in mice. In addition, the effects of quisqualate on the intracellular calcium response and on membrane currents mediated by TRPV1 channels, were examined in cultured dorsal root ganglion neurons from mice.

KEY RESULTS

Activation of mGlu5 receptors in hind paw transiently increased, then decreased, the response to noxious heat. In sensory neurons, activation of mGlu5 receptors potentiated TRPV1-mediated intracellular calcium elevation, while terminating activation of mGlu5 receptors depressed it. TRPV1-induced currents were potentiated by activation of mGlu5 receptors under voltage clamp conditions and these disappeared after washout. However, voltage-gated calcium currents were inhibited by the mGlu5 receptor agonist, even after washout.

CONCLUSIONS AND IMPLICATIONS

These results suggest that, in sensory neurons, mGlu5 receptors biphasically modulate TRPV1-mediated intracellular calcium response via transient potentiation of TRPV1 channel-induced currents and persistent inhibition of voltage-gated calcium currents, contributing to heat hyper- and hypoalgesia.

Dynamic changes of the inflammation-based index predict mortality following chemoembolisation for hepatocellular carcinoma: a prospective study

BACKGROUND

Transarterial chemoembolisation (TACE) is a standard treatment for unresectable, intermediate stage hepatocellular carcinoma (HCC). Survival after TACE, however, can be highly variable, with no suitable biomarker predicting therapeutic outcome. The inflammation-based index (IBI) has previously been shown to independently predict overall survival (OS) in all stages of HCC.

AIM

To explore the prognostic ability of IBI as a predictor of survival after TACE.

METHODS

Baseline staging, biochemical and clinicopathological features including IBI were studied in a derivation set of 64 patients undergoing TACE for intermediate stage HCC. Dynamic changes in IBI before and after TACE were studied as predictors of survival using both a univariate and multivariate Cox regression model and further validated in two independent patient cohorts from Korea (n = 76) and Japan (n = 577).

RESULTS

Pre-treatment IBI predicted for OS in the derivation set (P = 0.001). Other univariate predictors of OS included radiological response to TACE (P < 0.001), pre-TACE CLIP score (P < 0.01), tumour diameter >5 cm (P = 0.05) and AFP ≥400 (P < 0.001). Normalisation of IBI post-TACE was associated with radiological response by mRECIST criteria and improved OS (P < 0.001). Normalisation of IBI remained a significant multivariate predictor of OS in both the derivation and validation sets (P < 0.001).

CONCLUSIONS

Normalisation of IBI after TACE is shown to be an independent predictor of survival and may be integrated into the retreatment criteria for repeat TACE in intermediate stage HCC. IBI and its dynamic changes after treatment are validated as a biomarker allowing the stratification of patients with a significant survival advantage following initial TACE.

GIDEON (Global Investigation of therapeutic DEcisions in hepatocellular carcinoma and Of its treatment with sorafeNib): second interim analysis

BACKGROUND

GIDEON (Global Investigation of therapeutic DEcisions in hepatocellular carcinoma [HCC] and Of its treatment with sorafeNib) is a global, prospective, non-interventional study undertaken to evaluate the safety of sorafenib in patients with unresectable HCC in real-life practice, including Child-Pugh B patients who were excluded from clinical trials.

METHODS

Patients with unresectable HCC, for whom the decision to treat with sorafenib, based on the approved label and prescribing guidelines, had been taken by their physician, were eligible for inclusion. Demographic data and disease/medical history were recorded at entry. Sorafenib dosing and adverse events (AEs) were collected at follow-up visits. The second interim analysis was undertaken when ~1500 treated patients were followed up for ≥ 4 months.

RESULTS

Of the 1571 patients evaluable for safety, 61% had Child-Pugh A status and 23% Child-Pugh B. The majority of patients (74%) received the approved 800 mg initial sorafenib dose, regardless of Child-Pugh status; however, median duration of therapy was shorter in Child-Pugh B patients. The majority of drug-related AEs were grade 1 or 2, and the most commonly reported were consistent with previous reports. The incidence and nature of drug-related AEs were broadly similar across Child-Pugh, Barcelona Clinic Liver Cancer (BCLC) and initial dosing subgroups, and consistent with the overall population.

CONCLUSIONS

Consistent with the first interim analysis, overall safety profile and dosing strategy are similar across Child-Pugh subgroups. Safety findings also appear comparable irrespective of initial sorafenib dose or BCLC stage. Final analyses in > 3000 patients are ongoing.

Effect of hepatic arterial infusion chemotherapy of 5-fluorouracil and cisplatin for advanced hepatocellular carcinoma in the Nationwide Survey of Primary Liver Cancer in Japan

BACKGROUND

The efficacy of hepatic arterial infusion chemotherapy for the treatment of advanced hepatocellular carcinoma (HCC) remains unclear.

METHODS

The outcome of 476 patients with HCC who underwent hepatic arterial infusion chemotherapy with 5-fluorouracil and cisplatin (HAIC) were compared with 1466 patients who did not receive active therapy.

RESULTS

A survival benefit of the therapy after adjusting for known risk factors was observed (hazard ratio, 0.48; 95% CI, 0.41-0.56; P<0.0001). In propensity score-matched analysis (n=682), median survival time was longer for patients who underwent chemotherapy (14.0 months) than for patients who did not receive active treatment (5.2 months, P<0.0001).

CONCLUSION

For advanced HCC, HAIC is considered to be an effective treatment.

Guidelines and good clinical practice recommendations for contrast enhanced ultrasound (CEUS) in the liver--update 2012: a WFUMB-EFSUMB initiative in cooperation with representatives of AFSUMB, AIUM, ASUM, FLAUS and ICUS

Initially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging techniques. This joint WFUMB-EFSUMB initiative has implicated experts from major leading ultrasound societies worldwide. These liver CEUS guidelines are simultaneously published in the official journals of both organizing federations (i.e., Ultrasound in Medicine and Biology for WFUMB and Ultraschall in der Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis and improve the management of patients worldwide.

First interim analysis of the GIDEON (Global Investigation of therapeutic decisions in hepatocellular carcinoma and of its treatment with sorafeNib) non-interventional study

AIMS

Global Investigation of therapeutic DEcisions in hepatocellular carcinoma and Of its treatment with sorafeNib (GIDEON), a global, non-interventional, surveillance study, aims to evaluate the safety of sorafenib in all patients with unresectable hepatocellular carcinoma (uHCC) under real-life practice conditions, particularly Child-Pugh B patients, who were not well represented in clinical trials.

METHODS

Treatment decisions are determined by each physician according to local prescribing guidelines and clinical practice. Patients with uHCC who are candidates for systemic therapy, and for whom a decision has been made to treat with sorafenib, are eligible for inclusion. Demographic data and medical and disease history are recorded at entry. Sorafenib dosing and adverse events (AEs) are collected throughout the study.

RESULTS

From January 2009 to April 2011, >3000 patients from 39 countries were enrolled. The prespecified first interim analysis was conducted when the initial approximately 500 treated patients had been followed up for ≥4 months; 479 were valid for safety evaluation. Preplanned subgroup analyses indicate differences in patient characteristics, disease aetiology and previous treatments by region. Variation in sorafenib dosing by specialty are also observed; Child-Pugh status did not appear to influence the starting dose of sorafenib. The type and incidence of AEs was consistent with findings from previous clinical studies. AE profiles were comparable between Child-Pugh subgroups.

DISCUSSION

The GIDEON study is generating a large, robust database from a broad population of patients with uHCC. First interim analyses have shown global and regional differences in patient characteristics, disease aetiology and practice patterns. Subsequent planned analyses will allow further evaluation of early trends.