Electrochemotherapy of radioresistant head and neck squamous cell carcinoma cells and tumor xenografts.

Electrochemotherapy of radioresistant head and neck squamous cell carcinoma cells and tumor xenografts. Oncol Rep. 2019 Jan 09;: Authors: Zakelj MN, Prevc A, Kranjc S, Cemazar M, Todorovic V, Savarin M, Scancar J, Kosjek T, Groselj B, Strojan P, Sersa G Abstract Electrochemotherapy is an established local ablative method used for the treatment of different tumor types, including tumors of the head and neck area. Clinical studies have demonstrated a lower response rate of tumors that recur in pre‑irradiated area. The aim of the present study was to explore the response of experimentally induced radioresistant cells and tumors to electrochemotherapy with cisplatin or bleomycin. The radioresistant cells (FaDu‑RR) were established by fractionated irradiation of parental human squamous cell carcinoma cell line, FaDu. We compared the 2 cell lines in response to chemotherapy and electrochemotherapy with cisplatin or bleomycin in vitro and in vivo. Using specific mass spectrometry‑based analytical methods we determined the difference in the uptake of chemotherapeutics in tumors after electrochemotherapy. Additionally, we compared the capacity of the cells to repair DNA double‑strand breaks (DSB) after exposure to the drugs used in electrochemotherapy with the γH2AX foci resolution determined by immunofluorescence microscopy. Our results indicate radio‑ and cisplatin cross‑resistance, confirmed with the lower response rate of rad...
Source: Oncology Reports - Category: Cancer & Oncology Tags: Oncol Rep Source Type: research