RESUMO
BACKGROUND: Neoadjuvant/perioperative chemotherapy is the recommended treatment for advanced stages of gastric cancer (> T2, N+) before tumour resection in many European guidelines. However, there is no consensus as to whether perioperative chemotherapy is as effective in distal as in proximal tumours, in addition to a relevant uncertainty concerning appropriate treatment modalities for elderly patients. AIM: To investigate the role of perioperative chemotherapy in advanced gastric cancer in patients from a German tertiary clinic with respect to efficacy, localisation, and age. METHODS: We performed a retrospective analysis of 158 patients from our clinic with adenocarcinoma of the stomach or the gastroesophageal junction who underwent resection between 2008 and 2016. The data were evaluated particularly in relation to patient age, tumour site, and perioperative therapy. RESULTS: Administration of perioperative chemotherapy did not lead to a significant survival advantage in our study population. The 5-year survival rates were 40% for patients who received perioperative chemotherapy and 29% for the group without perioperative chemotherapy (P = 0.125). Our patients were on average distinctly older than patients in most of the published randomised controlled trials. Patients elder than 75 years received perioperative chemotherapy far less frequently. Patients with a proximal tumour received perioperative chemotherapy much more often. CONCLUSION: This analysis reconfirms our previous data concerning the effectiveness of perioperative chemotherapy for advanced gastric cancer. There is reasonable doubt that the quality of the existing randomized controlled trials is sufficient to generally justify perioperative chemotherapy in patients with advanced gastric cancer independent of tumour localization or age.
RESUMO
There is increasing evidence that food-derived polyphenols have a beneficial effect for cancers. Our purpose was to determine the effect and mechanism of action of these compounds on pancreatic cancer. We measured effects of quercetin on pancreatic cancer in a nude mouse model. We also investigated the effects of quercetin, rutin, trans-resveratrol and genistein on apoptosis and underlying signaling in pancreatic carcinoma cells in vitro. Quercetin decreased primary tumor growth, increased apoptosis and prevented metastasis in a model of pancreatic cancer. In vitro quercetin and trans-resveratrol, but not rutin, markedly enhanced apoptosis, causing mitochondrial depolarization and cytochrome c release followed by caspase-3 activation. In addition, the effect of a combination of quercetin and trans-resveratrol on mitochondrial cytochrome c release and caspase-3 activity was greater than the expected additive response. The inhibition of mitochondrial permeability transition prevented cytochrome c release, caspase-3 activation and apoptosis caused by polyphenols. Nuclear factor-kappa B activity was inhibited by quercetin and trans-resveratrol, but not genistein, indicating that this transcription factor is not the only mediator of the polyphenols' effects on apoptosis. The results suggest that food-derived polyphenols inhibit pancreatic cancer growth and prevent metastasis by inducing mitochondrial dysfunction, resulting in cytochrome c release, caspase activation and apoptosis.
