Intracellular structures responsible for cancer in the livers of rats are being subjected to powerful electron microscope scrutiny by Keith R. Porter, professor of Biology.

"By comparing the intracellular structure of normal liver cells to that of abnormal cells," Porter stated, "we hope to correlate the cell's rate of growth to its fine structure." Cancer cells, he pointed out, have an abnormally fast growth rate but fail to differentiate into specialized tissue.

Begun at Harvard's biological laboratories last September, Porter's current research uses a new $40,000 electron microscope. The shadow picture produced by introducing the cell specimen into a beam of electrons has a resolution of one fifty-millionth of an inch. Porter in 1945 made the first electron microscope photograph of a cell.

He devotes special attention to endoplasmic reticulum, the cellular structure involved in the synthesis of proteins which the cell transports. "The endoplasmic reticula of normal, differentiated cells," Porter said, "appear in patterns, which may be reflected in the forms of the cells. But in very malignant cells there is no pattern."

Virus Probably Not Responsible

Porter also finds that the growth of liver tumors he has observed does not depend on virus. "The growth may have been induced by a viral agent," he concluded, "but I don't think it's likely." Other forms of cancer, he added, may be virus-dependent.

Carlo Bruni, research fellow in Biology, and Guiseppe Millonig, research associate in Biology are working with the biologist under a grant from the National Cancer Institute. Students in Porter's course, Bio 223 (Topics and Techniques in Cytology), assist in preparing tissue for microscope study.

"This kind of work is attracting more and more students to the study of biology," Porter remarked.