A UCLA laboratory study presented earlier this year found that nicotine-laced vapor generated by an electronic cigarette promoted the development of cancer in certain types of human cells in much the same way cancer does, the New York Times reported. Researchers involved instudy emphasized that their findings were preliminary and that the study involved cells, not people. The study was supported by CTSI.
Further reading
New York Times: Early Data in E-Cigarette Study May Raise Safety Concerns
Press Release: Pre-Clinical Study Suggests E-Cigarettes May Promote Lung Cancer in High-Risk Individuals