Abstract 2052: Chemotherapy sensitivity, cytokine IL-8 level, and genetic expression mRNA IL-8 in gastric cancer treatment response prediction
Authors: (Yamada) Sirikan Limpakan 
Published: July 2017

Abstract
Aims: To determine chemotherapy sensitivity in primary gastric cancer cell isolated from Thai gastric cancer patients against anticancer drugs. To search for the correlation of interleukin-6 and interleukin-8 levels in primary gastric cancer cell culture in comparison with tissue mRNA IL-8 gene expression and drug response or resistance.
Method: The control background of corpus normal epithelial and gastric adenocarcinoma biopsy tissues were treated for primary cell culture with single cell isolation technique. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was performed to ex vivo examine the chemotherapy sensitivity to three anticancer drug, cisplatin, oxaliplatin, 5-Fluorouracil , and Irinotecan. Biopsy tissues from tumor site were collected before chemotherapy treatment in 63 patient who received neo-adjuvant chemotherapy by FOLFOX IV regimen due to advance stage III and IV in both resectable and un-resectable cases. The IL-8 mRNA gene expression was reported by relative quantitation real time RT-PCR. ELISA technique was performed to investigate the cytokine level from primary cultures taken from 41 gastric cancer patients who undergone biopsy from Maharaj Nakorn Chiang Mai Hospital during year 2014 to 2016. The clinical data base was parallel collected and analysed in correlation with clinical response and ex-vivo response.
Results: Each patient has different sensitivity pattern to the standard anticancer drugs. There are no significantly direct correlations or difference between cytokine IL-8 levels or mRNA IL-8 expression, and the chemotherapy sensitivity to the actual drugs that are being used for treatment of gastric adenocarcinoma in individual patients. However, the chemotherapy resistance to all drugs in primary gastric cancer cell culture has trend to increase after the third cycle of chemotherapy treatment when compared to prior cell treatment with fluctuation of cytokine level. Different cytotoxic drug gives the same response result for chemrsensitivity test in this population. The author observed the down regulation of tissue mRNA IL-8 expression and cytokine level in the good responders.
Conclusion: The results provide an additional basis of information for primary chemotherapy selection in the individualised treatment for advance gastric adenocarcinoma patients. Therefore, the author suggest to select the less toxicity cytotoxic drug for being primary chemotherapy of choice. Cytokine gene level and mRNA IL-8 gene expression show individually significantly change after chemotherapy treatment in good responder. This result may lead us to find some new targeted therapy or additional treatment for its suppression.
Citation Format: Sirikan Limpakan (Yamada). Chemotherapy sensitivity, cytokine IL-8 level, and genetic expression mRNA IL-8 in gastric cancer treatment response prediction [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2052. doi:10.1158/1538-7445.AM2017-2052