PurposeThe efficacy of neoadjuvant chemoradiotherapy (NCRT) plus surgery for locally advanced esophageal squamous cell carcinoma (ESCC) remains controversial. In this trial, we compared the survival and safety of NCRT plus surgery with surgery alone in patients with locally advanced ESCC.Patients and MethodsFrom June 2007 to December 2014, 451 patients with potentially resectable thoracic ESCC, clinically staged as T1-4N1M0/T4N0M0, were randomly allocated to NCRT plus surgery (group CRT; n = 224) and surgery alone (group S; n = 227). In group CRT, patients received vinorelbine 25 mg/m2 intravenously (IV) on days 1 and 8 and cisplatin 75 mg/m2 IV day 1, or 25 mg/m2 IV on days 1 to 4 every 3 weeks for two cycles, with a total concurrent radiation dose of 40.0 Gy administered in 20 fractions of 2.0 Gy on 5 days per week. In both groups, patients underwent McKeown or Ivor Lewis esophagectomy. The primary end point was overall survival.ResultsThe pathologic complete response rate was 43.2% in group CRT. Compared with group S, group CRT had a higher R0 resection rate (98.4% v 91.2%; P = .002), a better median overall survival (100.1 months v 66.5 months; hazard ratio, 0.71; 95% CI, 0.53 to 0.96; P = .025), and a prolonged disease-free survival (100.1 months v 41.7 months; hazard ratio, 0.58; 95% CI, 0.43 to 0.78; P < .001). Leukopenia (48.9%) and neutropenia (45.7%) were the most common grade 3 or 4 adverse events during chemoradiotherapy. Incidences of postoperative complications were similar between groups, with the exception of arrhythmia (group CRT: 13% v group S: 4.0%; P = .001). Peritreatment mortality was 2.2% in group CRT versus 0.4% in group S (P = .212).ConclusionThis trial shows that NCRT plus surgery improves survival over surgery alone among patients with locally advanced ESCC, with acceptable and manageable adverse events.

In actinomycetes, the onset of secondary metabolite biosynthesis is often triggered by the quorum-sensing signal ␥-butyrolactones (GBLs) via specific binding to their cognate receptors. However, the presence of multiple putative GBL receptor homologues in the genome suggests the existence of an alternative regulatory mechanism. Here, in the model streptomycete Streptomyces coelicolor, ScbR2 (SCO6286, a homologue of GBL receptor) is shown not to bind the endogenous GBL molecule SCB1, hence designated "pseudo" GBL receptor. Intriguingly, it could bind the endogenous antibiotics actinorhodin and undecylprodigiosin as ligands, leading to the derepression of KasO, an activator of a cryptic type I polyketide synthase gene cluster. Likewise, JadR2 is also a putative GBL receptor homologue in Streptomyces venezuelae, the producer of chloramphenicol and cryptic antibiotic jadomycin. It is shown to coordinate their biosynthesis via direct repression of JadR1, which activates jadomycin biosynthesis while repressing chloramphenicol biosynthesis directly. Like ScbR2, JadR2 could also bind these two disparate antibiotics, and the interactions lead to the derepression of jadR1. The antibiotic responding activities of these pseudo GBL receptors were further demonstrated in vivo using the lux reporter system. Overall, these results suggest that pseudo GBL receptors play a novel role to coordinate antibiotic biosynthesis by binding and responding to antibiotics signals. Such an antibiotic-mediated regulatory mechanism could be a general strategy to coordinate antibiotic biosynthesis in the producing bacteria.

In bacteria, many ''atypical'' response regulators (ARRs) lack the conserved residues important for phosphorylation by which typical response regulators switch their output response, suggesting the existence of alternative regulatory mechanisms. However, such mechanisms have not been established. JadR1, an OmpR-type ARR of Streptomyces venezuelae, appears to activate the transcription of jadomycin B (JdB) biosynthetic genes while repressing its own gene. JadR1 activities were inhibited in cells induced to produce JdB, which was found to bind directly to the N-terminal receiver domain of JadR1, causing JadR1 to dissociate from target promoters. The activity of a NarL-type ARR, RedZ, that regulates production of another antibiotic was likewise modulated by the end product (undecylprodigisines), implying that end-product-mediated control of antibiotic pathway-specific ARRs may be widespread. These results could prove relevant to knowledge-based improvements in yield of commercially important antibiotics.JadR1 ͉ ligand