Researchers who uncovered long-sought links between viruses and cancer that may play a crucial role in prevention and treatment of the disease were honored yesterday with one of the country's top research prizes.

The announcement of the winners of the prestigious Albert Lasker Basic Medical Research Award gave recognition to researchers who had spent long, seemingly fruitless years studying cancer viruses.

The awards also seemed to justify the major -- and often controversial -- financial investment in this field by the National Cancer Institute.

Dr. Robert C. Gallo, head of the Institute's tumor cell biology laboratory, was among those sharing the $15,000 prize. The other winners were Drs. J. Michael Bishop and Harold E. Varmus of the University of California, San Francisco, Dr. Hidesaburo Hanafusa of Rockefeller University, and Dr. Raymond L. Erikson of Harvard University.

While the scientists involved had long argued that their work with animal tumor viruses would help unravel how a cell becomes cancerous, critics often had questioned the relevance to human cancers. Recent studies, however, have found the first human cancer virus, as well as human cancer genes similiar to those found in animal tumor viruses.

"There is more at stake in all this than whether viruses cause cancer . . . The work that was recognized has raised the possibility that inside the cell is a single set of genes that represents the keyboard on which many different causes of cancer play," Bishop said in an interview yesterday.

Two other government scientists from this area, Drs. Roscoe O. Brady and Elizabeth F. Neufeld, also will share the Lasker Clinical Medical Research Award for studies contributing to the treatment of incurable genetic diseases of childhood. Brady heads a research unit at the National Institute of Neurological and Communicative Disorders and Stroke, and Neufeld is at the National Institute of Arthritis, Diabetes, Digestive and Kidney Diseases.

The awards are among the most coveted in U.S. medical research and often indicate that Nobel Prizes may follow.

In the 37 years that the awards have been given by the Albert and Mary Lasker Foundation in New York, 36 medical research winners later have become Nobel Laureates, including all three of the 1982 Nobel winners for medicine.

Gallo was cited for his "revolutionary discovery" of the first virus known to be associated with a human cancer.

The virus, known as human T-cell leukemia virus, leads to a deadly form of blood cancer that appears to be common in the Caribbean area and in Japan, and less common in the southeastern United States. Gallo expects that a simple blood test may be developed in the near future for the virus and later a vaccine may be produced for areas of the world at highest risk.

He and the other award winners do not believe, however, that viruses are the cause of most forms of human cancers, although Gallo is "confident we will find more."

Another approach has been the use of animal tumor viruses -- or "oncogenes" -- as probes in the search for human cancer.

These are sequences of genetic material that have been located in both normal and cancerous human cells and are similiar to those found in some well-studied animal tumor viruses.

Bishop and Varmus have shown that the forerunners of oncogenes are present throughout the animal world, including in man, and apparently play a role in normal cell function.

But, they suggested, when captured by a cancer virus or triggered by environmental chemicals or agents, these genes could cause abnormal growth and cancer.

Gallo said in an interview that new work in his laboratory in collaboration with researchers at the Wistar Institute in Philadelphia, as well as independent work at Harvard University, supports two possible mechanisms for activating the dormant cancer genes.

In what he called the "most compelling evidence that an oncogene is operative in human cancer," Gallo said that for the first time scientists had pinpointed the location of a known cancer gene that normally is located on one strand or chromosome of genetic material and jumps to another spot in human cancer cells.

Each human cell carries 23 pairs of chromosomes.

The gene, called the "myc" gene, is related to that found in chicken tumor viruses. Gallo said that while it is normally found on one end of the eighth pair of chromosomes, it often "translocates" to the 14th chromosomes in persons with Burkitt's lymphoma, a lymph system cancer common in some parts of Africa.

This suggests, he said, that in its new location the gene may be subject to "promoter" signals that turn it on and lead to abnormal growth. The new research, led by Dr. Riccardo Dalla-Favera in Gallo's lab, is expected to be published in the December issue of the Proceedings of the National Academy of Sciences.

Other recent studies also have found, said Gallo, that the same gene appears to be "amplified" by 20 to 30 fold in another form of human leukemia. While the cancers involved so far are rare, he said that such changes may well be identified in a "significant number of human cancers."