Cause Of Cancer May Be Known

Press, Volume CII, Issue 30192, 25 July 1963, Page 13

Cause Of Cancer May Be Known

(N.Z.P. A .-Reuter—Copy right) LONDON, July 24. Evidence that humans are naturally infected with viruses potentially capable of causing malignant tumours is reported by the General Medical Council.

The advance is mentioned in the council’s annual report.

The report says that in recent years the concept of viral neoplasia (disorganised, or new, growth) has received a stimulus from the discovery of a whole range of viruses that produce leukaemia and a variety of tumours in mice and hamsters. One virus—polyoma virus—-

injected into mice and hamsters, changed their cell structure.,

When the cells were transplanted into animals they caused tumours.

The report says study of polyoma virus as a model system could provide an experimental] approach to tumour viruses likely to afteot humans.

The report says two viruses that occur naturally in man—adenoviruses types 12 and 18 —had been shown to cause tumours in hamsters.

' Adenoviruses are a group which are common inhabitants of the human nasopharynx,” it says. “There is good evidence that many individuals have been infected at least with type 12. “There is thus for the first time evidence that humans are naturally infected with viruses potentially capable of causing malignant tumours.” It might be difficult to show that viruses actually caused tumours in humans.

The infectious agent might initiate a change during infection but then disappear before the tumour was detected, the report says.

"To inoculate human subjects in order to achieve the final experimental proof that any agent will cause tumours tn man is clearly unthinkable. “But a a result of the recent developments . . there is now some nope of testing the potentiality of a virus to cause tumours in bt iimans by examining its effects on human cells in culture, ratiher than by recourse o heroic expedients,” the report says.

Scepticism By Burnet

(N.Z. Press Assn.— Copyright) MELBOURNE, July 24. It was unlikely that more than a very small minority of human tumours would be shown to be caused by viruses. the Australian Nobel Prize-winner, Sir Macfarlane Burnet, said today. Commenting on the British Medical Research Council report, he said this line of research had been known for 10 years. It was being investigated by Dr. D. Metcalf, at the Walter and Eliza Hall Institute. he added. Sir Macfarlane Burnet won the 1960 Nobel Prize for Medicine and was awarded the Mueller Medal for an outstanding contribution to science in Australia and New Zealand in 1962. He is now director of the Walter and Eliza Hall Institute of Research to Melbourne.