Chemoradiation therapy (CRT) prior to surgery is increasingly the standard of care for locally advanced oesophageal cancer. Radiation therapy is important for local tumour control; however, tumour resistance to radiation is a substantial clinical problem. The mechanism(s) of radioresistance are still poorly understood, however, mounting evidence supports a role for microRNA (miRNA) in modulating key cellular pathways mediating response to radiation. Global miRNA profiling of an established isogenic model of radioresistance in oesophageal adenocarcinoma demonstrated a significant downregulation of miR-31 in radioresistant cells, both basally and in response to radiation. Ectopic re-expression of miR-31 significantly re-sensitised radioresistant cells to radiation. miR-31 was demonstrated to alter the expression of 13 genes involved in DNA repair, which is a critical cellular defence against radiation-induced DNA damage. In oesophageal tumours, miR-31 expression was significantly reduced in patients demonstrating poor histomorphologic response to neoadjuvant CRT, whilst expression of the miR-31-regulated DNA repair genes was significantly increased. Our data suggest a possible mechanism for resistance to CRT, potentially via enhanced DNA repair. This study demonstrates, for the first time, a role for miR-31 in modulating radioresistance and highlights the need for further study investigating the potential role of miR-31 as both a predictive marker of response and a novel therapeutic agent with which to enhance the efficacy of radiation therapy.
Niamh Lynam-Lennon, John V Reynolds, Laure Marignol, Orla M Sheils, Graham P Pidgeon and Stephen G Maher
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XBeam from Xstrahl Receives U.S. Food and Drug Administration (FDA) 510(k) Clearance for Use in the U.S.
Xstrahl’s XBeam has received FDA 510(k) Clearance for Use in the U.S. The XBeam technology streamlines radiotherapy treatment planning and simplifies patient workflow for treating skin cancer, benign diseases, and palliative care. Explore how this innovation enhances orthovoltage superficial radiotherapy (SRT) and electronic brachytherapy (eBt). With XBeam, you can calculate, protocol and export treatment plans for Xstrahl treatments with Radiant Aura and all other Xstrahl medical devices in the U.S. and worldwide.
