AIDS-associated virus linked to myeloma, second most common blood cancer in U.S. Study seen widening search for viruses in other cancers

In a surprising finding that is likely to intensify the hunt for viruses as causes of cancer, scientists in Los Angeles have linked an AIDS-associated virus with a common blood cancer.

The virus, Kaposi's sarcoma herpes virus, was discovered in 1994 among individuals who had AIDS and Kaposi's, a cancer that affects the skin and internal organs.


In the new study, the virus was linked to multiple myeloma, the second most common blood cancer in this country, after non-Hodgkin's lymphoma.

The Kaposi's virus was found in all 15 myeloma patients tested but not in 16 patients with other cancers and 10 healthy volunteers, the authors said in a report being published today in the journal Science.


The virus was also detected in patients with two related, but less common blood disorders, Waldenstrom's and amyloidosis, Dr. James Berenson, a co-author, said.

The scientists found the Kaposi virus only in noncancerous cells and not in the malignant myeloma ones. The Los Angeles team suspects that the Kaposi's sarcoma virus may cause myeloma indirectly by the infected cells chemically stimulating other cells to become malignant.

Infection seemed to be limited to the dendritic cells that help provide structure to the bone marrow, said Berenson's team from the Veterans Affairs Medical Center in Los Angeles and the University of California at Los Angeles.

The study was too limited in scope to prove that Kaposi's sarcoma virus causes myeloma. Much more research would be required to make that case and to learn how the Kaposi's sarcoma virus is transmitted.

Nevertheless, scientists who did not take part in this study said that the unexpected finding would lead them to widen their search for viruses in other cancers.

While Kaposi's has occurred commonly among men with AIDS, the incidence of myeloma has increased only slightly, possibly because AIDS patients have not lived long enough to develop it.

The findings also have important implications for myeloma. Evidence that the Kaposi's sarcoma virus plays a major role in it could lead to new therapies aimed at the virus, not the cancerous cells. And the findings raise a theoretical possibility of developing a vaccine to prevent myeloma, the authors said.

But scientists cautioned that confirmation would be needed to clarify issues about techniques used in the study.


Pub Date: 6/20/97