Randomized phase III trial of docetaxel plus carboplatin with or without levofloxacin prophylaxis in elderly patients with advanced non-small cell lung cancer: the APRONTA trial.

PURPOSE: To examine the effect of levofloxacin prophylaxis on infection rates during chemotherapy with docetaxel plus carboplatin in elderly patients with advanced non-small cell lung cancer. METHODS: In a randomized, double-blind, phase III study, patients (≥65 years) with untreated, histologically/cytologically proven stage IIIB/IV non-small cell lung cancer received docetaxel (75 mg/m) plus carboplatin (area under the curve 6) on day 1 every 3 weeks, plus once-daily levofloxacin (500 mg orally) or placebo on days 5 to 11. The primary end point was the rate of grade 3/4 infections or grade 1/2 infections treated with additional antibiotics. Secondary end points included overall infection rate, toxicity, overall survival, and progression-free survival. RESULTS: In total, 187 patients were randomized to levofloxacin (n = 95) or placebo (n = 92). The rate of grade 3/4 infections or grade 1/2 infections treated with additional antibiotics (intent-to-treat population) was 27.5% (95% confidence interval, 19.3-39.0%) for levofloxacin versus 36.7% (95% confidence interval, 27.1-48.0%) for placebo. Median time to first infection was 67 days for levofloxacin versus 46 days for placebo. Grade 3/4 infections occurred in 8.8% of patients in the levofloxacin group versus 26.7% for placebo. There was one grade 5 infection in each group. Grade ≥3 toxicities (levofloxacin versus placebo) included leukopenia (63.2 versus 52.2%), neutropenia (62.1 versus 51.1%), dyspnea (12.6 versus 8.7%), and pain (10.5 versus 9.8%). There was no significant difference in overall survival or progression-free survival between groups. CONCLUSIONS: Levofloxacin prophylaxis reduces the rate of infection compared with placebo and is well tolerated in elderly patients receiving docetaxel plus carboplatin.

Myosin Va facilitates the distribution of secretory granules in the F-actin rich cortex of PC12 cells.

Neuroendocrine secretory granules, the storage organelles for neuropeptides and hormones, are formed at the trans-Golgi network, stored inside the cell and exocytosed upon stimulation. Previously, we have reported that newly formed secretory granules of PC12 cells are transported in a microtubule-dependent manner from the trans-Golgi network to the F-actin-rich cell cortex, where they undergo short directed movements and exhibit a homogeneous distribution. Here we provide morphological and biochemical evidence that myosin Va is associated with secretory granules. Expression of a dominant-negative tail domain of myosin Va in PC12 cells led to an extensive clustering of secretory granules close to the cell periphery, a loss of their cortical restriction and a strong reduction in their motility in the actin cortex. Based on this data we propose a model that implies a dual transport system for secretory granules: after microtubule-dependent delivery to the cell periphery, secretory granules exhibit a myosin Va-dependent transport leading to their restriction and even dispersal in the F-actin-rich cortex of PC12 cells.