Heat sensitivity between human normal liver (WRL68) and breast cancer (MDAMB 231) cell lines

Abstract

Hyperthermia is an innovative method for various types of cancer treatments which has potential to increase cytotoxic effect within the tumor volume, without increase normal tissue toxicity. In the present study, it was aimed to investigate temperature and duration of heat shock on viability of human normal liver (WRL-68) and breast carcinoma (MCF-7) cell lines using MTT and methylene blue assay. These cells were exposed to heat at three different temperatures (38, 40 and 42°C) for five different duration of heat exposure (0.5, 1, 2, 3 and 4 hrs.). Viability of WRL-68 and MCF-7 cell lines is highly influenced by temperature and duration of hyperthermic exposure. After increasing temperature from 38 to 42°C, more cancer cells were killed during the same period of heat exposure compare to normal cells. This was due to MCF-7 cells do not have defense system against heat, as do WRL-68 cells. There was a great variation of thermo sensitivity among normal cell and cancer cell. In this study, it was clearly observed that WRL-68 cells were killed at 42°C for 3 hrs. meanwhile MCF-7 cells need temperature of 38°C for 0.5 hrs. In future, more synergistic effects of combining hyperthermia with chemotherapy, radiotherapy, immunotherapy or gene therapy must be study in order to develop better therapeutic effects in breast cancer treatment.