Inorganic polyphosphate enhances radio-sensitivity in a human non–small cell lung cancer cell line, H1299. Issue 6 (June 2017)

• Record Type: Journal Article
• Authors: Tsutsumi, Kaori; Matsuya, Yusuke; Sugahara, Tomoki; Tamura, Manami; Sawada, Satoshi; Fukura, Sagiri; Nakano, Hisashi; Date, Hiroyuki
• Is Part Of: Tumor biology. Volume 39:Issue 6(2017)
• Publication Date: 2017-06
• Subjects: Inorganic polyphosphate -- radio-sensitivity -- non–small cell lung cancer -- adenosine triphosphate -- mitochondria; Cancer -- Periodicals; Oncology -- Periodicals; Tumors -- Periodicals; 616.994
• DOI: 10.1177/1010428317705033
• Languages: English
• ISSNs: 1010-4283

Abstract

Inorganic polyphosphate is a linear polymer containing tens to hundreds of orthophosphate residues linked by high-energy phosphoanhydride bonds. Polyphosphate has been recognized as a potent anti-metastasis reagent. However, the molecular mechanism underlying polyphosphate action on cancer cells is poorly understood. In this study, we investigated the involvement of polyphosphate in radio-sensitivity using a human non–small cell lung cancer cell line, H1299. We found that polyphosphate treatment decreases cellular adenosine triphosphate levels, suggesting a disruption of energy metabolism. We also found that the induction of DNA double-strand breaks was enhanced in polyphosphate-treated cells after X-ray irradiation and colony formation assay revealed that cell survival decreased compared with that of the control groups. These findings suggest that polyphosphate is a promising radio-sensitizer for cancer cells. Therefore, we hypothesized that polyphosphate treatment disrupts adenosine triphosphate–mediated energy transfer for cellular survival and DNA repair, thereby reducing the cellular capability to resist X-ray irradiation.