A pilot trial of FLOT neoadjuvant chemotherapy for resectable esophagogastric junction adenocarcinoma.

Docetaxel is active in esophagogastric junction (EGJ) adenocarcinoma, and DCF (docetaxel/cisplatin/5-fluorouracil) has shown good results in the neoadjuvant setting. Its high rate of grade 3-4 mucosal toxicity (stomatitis and diarrhea) has limited its widespread adoption. A more recent docetaxel-based triplet, FLOT (5-fluorouracil, oxaliplatin and docetaxel) may be better tolerated. We conducted a pilot study of FLOT chemotherapy in EGJ adenocarcinoma patients and dysphagia to prospectively assess the rate of grade 3-4 mucosal toxicity and of pathological complete response (pCR) rate. Dysphagia and quality of life were measured with validated questionnaires. Ten patients were enrolled. Grade 3-4 mucosal toxicity rate was 0 %; pCR rate was 11 %; and near-complete pathological response rate 11 %. Dysphagia improvement or resolution was seen in 90 % of patients, and quality of life was stable before and after chemotherapy. FLOT is a safe and active neoadjuvant chemotherapy option for EGJ adenocarcinoma and should be compared to other standard regimens in randomized trials.

Buthionine sulfoximine embryotoxicity is associated with prolonged AP-1 activation.

BACKGROUND: Many teratogens induce oxidative stress, altering redox status and redox signaling; this has led to the suggestion that developmental toxicants act by disturbing redox status. The goal of these studies was to determine the consequences of altering glutathione homeostasis during organogenesis on embryo development, total DNA methylation, and activator protein-1 (AP-1) DNA binding activity and gene expression. METHODS: Gestational day 10.5 rat embryos were cultured in vitro for up to 44 hour in the presence of L-buthionine-S,R-sulfoximine (BSO), an irreversible inhibitor of gamma-glutamyl-cysteine synthetase, the rate limiting step in glutathione biosynthesis. Effects of BSO on total, oxidized and reduced glutathione, embryo development, DNA methylation, AP-1 DNA binding activity and gene expression were investigated. RESULTS: Significant depletion of glutathione by BSO was first noted at 6 hr in the embryo and at 3 hr in the yolk sac; total glutathione in the conceptus was depleted to the same extent after treatment with either 0.1 or 1.0 mM BSO. Exposure to 0.1 mM BSO did not cause a significant increase in embryotoxicity, although some impairment of growth and development was observed. In contrast, exposure to 1.0 mM BSO severely inhibited growth and development, significantly increasing the incidence of swollen hindbrains and of blebs in the forebrain, limb and maxillary regions. No significant treatment-related differences in total DNA methylation were observed. Interestingly, AP-1 DNA binding activity was similar in control and 0.1 mM BSO-treated conceptuses; however, exposure to 1.0 mM BSO increased AP-1 DNA binding at 6, 24, and 44 hr. The expression of several AP-1 family genes and of gamma-glutamylcysteine synthetase was induced in embryos cultured with 1.0 mM BSO. CONCLUSION: Exposure of embryos in vitro to BSO at a concentration that was embryotoxic induced prolonged AP-1 DNA binding activity and altered gene expression. These data suggest that AP-1 induction may serve as a biomarker of embryo stress.