Open AccessInfluence of stem‐cell cycle time on accelerated re‐population during radiotherapy in head and neck cancer
Author(s) -
Marcu L. G.,
Bezak E.
Publication year - 2012
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/j.1365-2184.2012.00832.x
Subject(s) - radiation therapy , stem cell , population , cell cycle , cancer stem cell , cell division , medicine , cell , cancer research , oncology , biology , cancer , microbiology and biotechnology , genetics , environmental health
Objectives Tumour re‐population during radiotherapy was identified as an important reason for treatment failure in head and neck cancers. The process of re‐population is suggested to be caused by various mechanisms, one of the most plausible one being accelerated division of stem‐cells (i.e. drastic shortening of cell cycle duration). However, the literature lacks quantitative data regarding the length of tumour stem‐cell cycle time during irradiation. Materials and methods The presented work suggests that if accelerated stem‐cell division is indeed a key mechanism behind tumour re‐population, the stem‐cell cycle time can drop below 10 h during radiotherapy. To illustrate the possible implications, the mechanism of accelerated division was implemented into a Monte Carlo model of tumour growth and response to radiotherapy. Tumour response to radiotherapy was simulated with different stem‐cell cycle times (between 2 and 10 h) after the initiation of radiotherapy. Results It was found that very short stem‐cell cycle times lead to tumour re‐population during treatment, which cannot be overcome by radiation‐induced cell kill. Increasing the number of radiation dose fractions per week might be effective, but only for longer cell cycle times. Conclusion It is of crucial importance to quantitatively assess the mechanisms responsible for tumour re‐population, given that conventional treatment regimens are not efficient in delivering lethal doses to advanced head and neck tumours.