PHILADELPHIA – The major active component of marijuana could enhance the ability of the virus that causes Kaposi’s sarcomaterm to infect cells and multiply, according to a team of researchers at Harvard Medical School. According to the researchers, low doses of Ä-9 tetrahydrocannabinol (THC), equivalent to that in the bloodstream of an average marijuana smoker, could be enough to facilitate infection of skin cells and could even coax these cells into malignancy.

While most people are not at risk from Kaposi’s sarcoma herpes virus (KSHV), researchers say those with lowered immune systems, such as AIDS patients or transplant recipients, are more susceptible to developing the sarcoma as a result of infection. Their findings, reported in the August 1 issue of Cancer Research, a journal of the American Association for Cancer Research, offer cautionary evidence that those with weakened immune systems should speak with their doctors before using marijuana medicinally or recreationally.