Relation between Ku80 and microRNA-99a expression and late rectal bleeding after radiotherapy for prostate cancer. Issue 2 (May 2015)

• Record Type: Journal Article
• Authors: Someya, Masanori; Yamamoto, Hiroyuki; Nojima, Masanori; Hori, Masakazu; Tateoka, Kunihiko; Nakata, Kensei; Takagi, Masaru; Saito, Masato; Hirokawa, Naoki; Tokino, Takashi; Sakata, Koh-ichi
• Is Part Of: Radiotherapy and oncology. Volume 115:Issue 2(2015:May)
• Page Start: 235
• Page End: 239
• Publication Date: 2015-05
• Subjects: Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2015.04.008
• Languages: English
• ISSNs: 0167-8140

Abstract

<abstract xml:lang="en" abstract-type="author" id="ab005"> <title id="st005">Abstract</title> <sec> <title id="st010">Background and purpose</title> <p id="sp0005">Late rectal bleeding is one of the severe adverse events after radiotherapy for prostate cancer. New biomarkers are needed to allow a personalized treatment.</p> </sec> <sec> <title id="st015">Materials and methods</title> <p id="sp0010">Four patients each with grade 0–1 or grade 2–3 rectal bleeding were randomly selected for miRNA array to examine miRNA expression in peripheral blood lymphocytes (PBLs). Based on results of miRNA array, 1 of 348 miRNAs was selected for microRNA assays. Then, expression of DNA-dependent protein kinase mRNA and miR-99a was analyzed in the PBLs of 97 patients. PBLs were exposed to 4 Gy of X-ray ex-vivo.</p> </sec> <sec> <title id="st020">Results</title> <p id="sp0015">In the discovery cohort, grade 2–3 rectal bleeding was significantly higher in the Ku80 <1.09 expression group compared with ⩾1.09 group (<italic>P</italic> = 0.011). In radiation-induced expression of miR-99a, grade 2–3 rectal bleeding was significantly higher in the miR-99a IR(+)/IR(−) >0.93 group compared with ⩽0.93 group (<italic>P</italic> = 0.013). Most patients with grade 2–3 rectal bleeding were in the group with low Ku80 and high miR-99a expression. In the validation cohort, similar results were obtained.</p> </sec> <sec> <title id="st025">Conclusion</title> <p id="sp0020">A combination of low Ku80 expression and highly-induced miR-99a expression could be a promising marker for predicting rectal bleeding after radiotherapy.</p> </sec> </abstract>