Tumorgenic properties of high-dose ionizing radiation of primary cancer-associated fibroblasts

In the context of radiotherapy, the effects elicited by ionizing radiation on the supportive stroma of tumors remains understudied. Tumor infiltrating fibroblasts are abundantly found in the stromal tissue of most tumor types and are key determinants of tumor progression and metastasis. Given the clinical attention that ablative radiotherapy is gaining nowadays, and the paramount role played by CAFs in cancer sustainability, in this study the effect of high-dose ionizing radiation on primary CAF?S have been investigated. We have used high-throughput transcriptome analysis to ascertain in which degree tumor stromal fibroblast become pro-tumorigenic or anti-tumorigenic after ablative irradiation. Hence, genome-wide transcriptome analysis has been carried out on CAFs isolated from NSCLC tumors after receiving a single dose of 18 Gray. The expressions of relevant genes have been validated by real-time PCR, and transformed cellular pathways have been checked by functional assays. Overall, our data reveals profound changes in biological pathways including cellular stress, DNA damage, cell cycle, aging, apoptosis, oxidative stress, and matrix remodeling. Ablative radiation doses may exert both pro-and anti-tumorigenic effects on CAFs. The ultimate effect of such disturbances merits further investigation in more complex in vivo settings. Established primary cancer-associated fibroblasts (CAFs) obtained from non-small-cell lung cancer (NSCLC) patient material were irradiated with a single dose of 18 Gy and total RNA was isolated 24 hrs after treatment.