Author/Editor		Prevc, Ajda; Kranjc, Simona; Čemažar, Maja; Todorović, Vesna; Žegura, Bojana; Novak, Matjaž; Filipič, Metka; Strojan Fležar, Margareta; Srebotnik-Kirbiš, Irena; Rotter, Ana; Brožič, Andreja; Nikšić Žakelj, Martina; Poljak, Mario; Hošnjak, Lea; Grošelj, Blaž; Strojan, Primož; Serša, Gregor
Title		Dose-modifying factor of radiation therapy with concurrent cisplatin treatment in HPV-positive squamous cell carcinoma
Type		članek
Vol. and No.		Letnik 189, št. 6
Publication year		2018
Volume		str. 644-651
ISSN		0033-7587 - Radiation research
Language		eng
Abstract		Human papillomavirus (HPV) is an important etiological factor in oropharyngeal squamous cell carcinoma (SCC). Compared to HPV-negative tumors, HPV-positive oropharyngeal SCC has shown a better response to nonsurgical treatments. In this study, we determined the dose-modifying factors for HPV-positive tumors with single-dose irradiation, with or without low radiosensitizing doses of cisplatin. In vitro, we determined an increased radiosensitivity of HPV-positive SCC, which might be a consequence of HPV-induced changes in the cell cycle regulation and DNA damage response, leading to increased cell death. Additionally, compared to HPV-negative tumors, 30% higher radiosensitivity of HPV-positive tumors was determined by tumor growth delay monitoring in immunodeficient mice in vivo. Concurrent cisplatin treatment had an additive effect in both HPV-negative and HPV-positive tumors, resulting in 20% better response in HPV-positive tumors than in HPV-negative tumors.
Keywords		ploščatocelični rak humani papilomski virus rak grla cisplatin squamous cell carcinoma HPV oropharyngeal carcinoma cisplatin