Abstract 1441: Effect of chemotherapy on cytokine production by solid tumor cell lines.
Authors: Herlinger Alice L. , Valadão Iuri C. , de Souza Mariana C. , Heniques Maria das Graças MO , Caruso-Neves Celso , Rangel Leticia BA 
Published: August 2014

Tumor microenvironment strongly influences cancer progression, regulating several cellular processes and cancer immune surveillance. Albeit the influence of cytokines from immune cells on tumor progression has already been described, little is known on the role of cancer cells on the production of these cytokines, especially in response to chemotherapy. To address this aspect of tumor biology, we exposed the serous epithelial ovarian cancer (EOC) cell line A2780, the clear cell EOC cell line TOV21G, the endometrioid EOC cell line MDAH-2774 (further referred as 2774), the breast cancer (BC) cell line MDA-MB 231, and the non-small cell lung carcinoma (NSCLC) cell line A549 to cisplatin (CI), cyclophosphamide (CY), doxorubicin (DO), and paclitaxel (PA) for 5 days, at their IC50 range, prior to cytokine measurement by ELISA in cell's conditioned media (CM). Cytokines (IL-17, IFN-γ, CXCL-1, and TGF-β) were measured in the pool of CM from 3 well after 3 and 5 days of exposure to each drug or untreated cells (UT). Results were normalized by the mean protein content of wells and are expressed in pg/mL/μg of protein. Cytokines’ level varied among UT cell lines, probably reflecting tumor heterogeneity. IL-17 secretion was higher in 2774, MDA-MB 213 and A549 (4.6, 8.9, and 10.6, respectively). UT TOV21G cells did not secrete IL-17. In response to CI, IL-17 levels decreased; whereas response to the other drugs greatly varied. INF-γ levels showed the lesser variation among cell lines (0.01 - 0.2). Upon exposure to the drugs, IFN-γ secretion tend to increase by all drugs in A2780 and 2774 lines, and in TOV21G exposed to CY; however it was strongly decreased by PA in this line and in A549. EOC cells A2780 and 2774 were the only lines secreting CXCL-1 in UT condition (∼0.015 on D5). CXCL-1 secretion in most conditions either was unaltered or decreased. However, CI was the only drug that induced its secretion in A2780, TOV21G and MDA-MB 231. As this chemokine has already been described as a factor promoting tumor cell migration and invasion, the relation between CI and CXCL-1 is worth of further analysis. Worth noticing, TGF-β was highly secreted by NSCLC cells (42.7 on D5); all other cells’ level was &lt; 0.96 on D5. The most striking change was in A540 where all drugs decreased its levels, especially CI (0.73 on D5). Similar data were observed in A2780 cells, which is not in concordance with our previous data. This finding highlights the importance of precisely define drug dose in cancer therapy and its impact on patients’ clinical outcome, as the assays were conducted under distinct CI concentration. Overall, our data corroborated the great heterogeneity among different cancers and its response to chemotherapy, also highlighting the importance to consider the effect of different drugs on tumor immune surveillance, therefore introducing a novel aspect in predicting tumor responsiveness to conventional antineoplastic drugs, and ultimately to control cancer progression.

Citation Format: Alice L. Herlinger, Iuri C. Valadão, Mariana C. de Souza, Maria das Graças MO Heniques, Celso Caruso-Neves, Leticia BA Rangel. Effect of chemotherapy on cytokine production by solid tumor cell lines. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1441. doi:10.1158/1538-7445.AM2013-1441