A multicenter phase II study of pazopanib in patients with advanced gastrointestinal stromal tumors (GIST) following failure of at least imatinib and sunitinib.

BACKGROUND: Advanced GISTs are incurable, but often treatable for years with tyrosine kinase inhibitors (TKIs). The majority of GISTs harbor an oncogenic activating mutation in KIT or PDGFRA. Inhibition of this activating mutation with TKIs most often leads to durable disease control for many patients. However, almost all patients develop resistance to these TKIs, typically due to the development of secondary mutations, heralding the need for new therapeutic options. We conducted a phase II study evaluating the efficacy and toxicity of pazopanib, a broad spectrum TKI inhibiting KIT, VEGFRs (-1, -2, and -3), and PDGFR (-α and-ß) in patients with advanced GIST following failure of at least imatinib and sunitinib. METHODS: Patients received pazopanib 800 mg orally once daily. All patients were assessed for efficacy with CT scans every 8 weeks (two cycles). Patients continued pazopanib until progression or unacceptable toxicity. The primary end point was the 24-week nonprogression [complete response+partial response+stable disease (SD)] rate (NPR) per RECIST 1.1. Secondary end points included PFS, OS, and toxicity. RESULTS: Between August 2011 and September 2012, a total of 25 patients were treated at two institutions. Median number of prior therapy was 3 (range 2-7). A total of 90 cycles of pazopanib were administered, with a median of two cycles (range 1 to 17+) per patient. Best response of SD at any time was observed in 12 (48%) patients. The NPR was 17% [95% confidence interval (CI) 4.5-37]. All but one patient discontinued protocol either due to PD (n = 19) or intolerance (n = 4). One patient with succinate dehydrogenase (SDH)-deficient GIST exhibited continuing disease control after 17 cycles. The median PFS for the entire cohort was 1.9 months (95% CI 1.6-5.2), and the median OS was 10.7 months (95% CI 3.9-NR). CONCLUSIONS: Pazopanib was reasonably well tolerated with no unexpected toxicities. Pazopanib as a single agent has marginal activity in unselected heavily pretreated patients with advanced GIST.

Phase II study of the HSP90-inhibitor BIIB021 in gastrointestinal stromal tumors.

BACKGROUND: HSP90 inhibition leads to proteosomal degradation of activated KIT and has in vitro activity against gastrointestinal stromal tumors (GIST). BIIB021 is an oral non-ansamycin HSP90 inhibitor. We carried out a phase II study of BIIB021 in patients with GIST refractory to imatinib and sunitinib. PATIENTS AND METHODS: The primary end-point was metabolic partial response (mPR) as assessed by fluorodeoxyglucose positron emission tomography (FDG-PET). The secondary end-points were pharmacokinetic assessments of BIIB021 and pharmacodynamic assessments of HSP70. Twenty-three patients were treated on two schedules: 12 pts received 600 mg twice a week (BIW) and 11 patients received 400 mg three times a week (TIW). All had prior imatinib and sunitinib but stopped>14 days before starting BIIB021. RESULTS: The median age was 59 years (33-88 years), 61% male, 44% Eastern Cooperative Oncology Group 1 (ECOG1). The best response was PR by FDG-PET for five patients (3/12 at 600 mg BIW and 2/9 at 400 TIW) for an overall response rate of 22%. The response duration was 25-138 days. Adverse events (AEs) were mild to moderate. The mean Cmax was 1.5 µmol and the mean AUC was 2.9 µmol h. Cmax>1.5 µmol was associated with a decrease in standardized uptake value (SUVmax). HSP70 increased substantially following treatment. CONCLUSIONS: This study met its primary end-point. BIIB021 leads to objective responses in refractory GIST patients. Pharmacodynamic studies confirmed HSP90 inhibition. Further evaluation of BIIB021 in GIST is warranted.

The effect of harmonic context on phoneme monitoring in vocal music.

The processing of a target chord depends on the previous musical context in which it has appeared. This harmonic priming effect occurs for fine syntactic-like changes in context and is observed irrespective of the extent of participants' musical expertise (Bigand & Pineau, Perception and Psychophysics, 59 (1997) 1098). The present study investigates how the harmonic context influences the processing of phonemes in vocal music. Eight-chord sequences were presented to participants. The four notes of each chord were played with synthetic phonemes and participants were required to quickly decide whether the last chord (the target) was sung on a syllable containing the phoneme /i/ or /u/. The musical relationship of the target chord to the previous context was manipulated so that the target chord acted as a referential tonic chord or as a congruent but less structurally important subdominant chord. Phoneme monitoring was faster for the tonic chord than for the subdominant chord. This finding has several implications for music cognition and speech perception. It also suggests that musical and phonemic processing interact at some stage of processing.

Epidemiology of social phobia: a clinical approach.

The recent epidemiologic studies report extremely varied rates for social phobia (SP). One of the reasons for this may be the difficulty in diagnosing SP, the boundaries of which are uncertain. A community survey was carried out using doctors with experience in clinical psychiatry as interviewers, and a clinical diagnostic instrument. Two thousand three hundred and fifty-five people (out of the 2,500 randomly selected from the population) living in Sesto Fiorentino, a suburb of Florence, Italy, were interviewed by their own general practitioner, using the MINI plus six additional questions. Six hundred and ten of the 623 subjects that were found positive for any form of psychopathology at the screening interview, and 57 negative subjects, were re-interviewed by residents in psychiatry using the Florence Psychiatric Interview (FPI). The FPI is a validated composite instrument that has the format of a structured clinical research record. It was found that 6.58% of subjects showed social anxiety not attributable to other psychiatric or medical conditions during their life. Social or occupational impairments meeting DSM-IV diagnostic requirements for SP was detected in 76 subjects (lifetime prevalence = 3.27%). Correction for age raises the lifetime expected prevalence to 4%. Sex ratio was approximately (F:M) 2:1. The most common fear was speaking in public (89.4%), followed by entering a room occupied by others (63.1%) and meeting with strangers (47.3%). Eighty-six point nine percent of subjects with SP complained of more than one fear. The mean age of onset (when the subjects first fully met DSM-IV criteria for SP) was 28.8 years, but the first symptoms of SP usually occurred much earlier, with a mean age of onset at 15.5 years. Ninety-two percent of cases with SP also showed at least one other co-morbid psychiatric disorder during their life. Lifetime prevalence of avoidant personality disorder (APD) was 3.6%. Forty-two point nine percent of cases with SP also had APD, whereas 37.9% of cases with APD developed SP.

rsc: a novel oncogene with structural and functional homology with the gene family of exchange factors for Ral.

A novel oncogene, rsc (rabbit squamous cell carcinoma), has been identified from a DMBA-induced rabbit squamous cell carcinoma using gene transfer and the nude mouse tumorigenesis assay. A full-length cDNA has been isolated and sequenced. rsc has potent tumorigenic activity in nude mice (latency <4 weeks), but does not induce focus formation or anchorage independent growth. The oncogene resulted from the fusion of rHR 23A (a rabbit homologue of yeast Rad 23) with a member of the ral-GDS family which we named rgr (ral-GDS related). Deletion analysis demonstrated that the oncogenic potential resides in the Rgr portion of the gene. Rgr is 40% identical overall to Ral-GDS, with identity increasing to 72% over a 100 amino acid region of the catalytic domain. Biochemical experiments indicate that Rgr has GTP/GDP exchange activity for Ral, providing evidence that this pathway is associated with tumorigenesis. The linkage between the Ral pathway and tumorigenesis by a molecule in the Ral-GDS gene family (Ral-GDS being a known effector for Ras) will open the way for the characterization of this pathway and provide an important tool to understand its biological function.