Researchers from the Fred Hutchinson Cancer Research Center in Seattle found that chemotherapy increases production of a protein which causes cancer cells to grow and resist treatment, the BBC reported.
The study looked at fibroblast cells, which normally play a critical role in wound healing and the production of collagen, the main component of connective tissue such as tendons.
Chemotherapy causes damage to DNA or deoxyribonucleic acid which leads the fibroblasts to produce up to 30 times more of a protein called WNT16B than they should.
The protein fuels cancer cells to grow and invade surrounding tissue - and to resist chemotherapy.
"Cancer therapies are increasingly evolving to be very specific, targeting key molecular engines that drive the cancer rather than more generic vulnerabilities, such as damaging DNA," Peter Nelson, who led the research, was quoted as saying by the BBC.
"Our findings indicate that the tumour microenvironment also can influence the success or failure of these more precise therapies," Nelson said.
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Around 90 per cent of patients with solid cancers, such as breast, prostate, lung and colon, that spread - metastatic disease - develop resistance to chemotherapy.
Treatment is usually given at intervals, so that the body is not overwhelmed by its toxicity. But that allows time for tumour cells to recover and develop resistance.
The study was published in Nature Medicine.