Side-effects of conventional treatment can be avoided Hong Kong biochemists have discovered a novel method to kill cancer cells without interfering with the functions of normal cells. The discovery, published in the latest issue of the US journal Cancer Research, a leading publication in the field, may avoid the severe side-effects associated with conventional cancer treatment. According to Hong Kong University of Science and Technology (HKUST) biochemist Chun Liang, his research team discovered that abnormal cancerous cells will die on their own if their replication cycles is interrupted at a genetic level while healthy cells, aside from not being able to reproduce, continue to perform normal biological functions. 'I have suspected this for several years. What we have done in this research paper is to prove that,' said Dr Liang, an assistant professor in the university's biochemistry department. For cells to divide and reproduce, they must first replicate their DNA. Six protein types have now been identified as being triggers for DNA replication in both healthy and cancer cells. Dr Liang and his team have devised a group of interfering molecules that halt the activities of three of the six replication-initiation proteins. Their experiments were carried out on human cancer-cell samples. Stopping any one of those six proteins will halt cell reproduction and replication cycles, leading cancer cells to die off in a process called apoptosis. But the three protein types were targeted by the HKUST team because they were found not to interfere with normal biological activities, thus minimising damage to healthy cells. 'Inhibiting the expression of these proteins should effectively abate DNA replication, stopping cancer growth while leaving most normal cells in the body largely unaffected,' the group wrote in Cancer Research. 'These proteins may therefore present attractive targets for development of effective anti-cancer drugs with few side effects.' But Dr Liang cautioned that the discovery was still at the basic research level and several years of research and development involving animal testing and clinical trials with humans would be needed for any effective drug treatment to reach the clinic. Dr Liang, a mainland and US-trained biochemist, is a rising star in the Hong Kong scientific community. He has previously helped discover two of the six replication proteins.