The CancerWeb Report, What's New In Cancer: November, 1996
Hematologic Malignancy

• Hairy cell leukemia - Hairy cell leukemia (HCL) is an unusual disease, firstly because in its natural course there is an early deficiency in one type of white cells, the mononuclear monocytes, followed by a progressive loss of all cell types in the blood, and secondly because of its unique sensitivity and response to interferon alpha. A study by researchers in Vienna, Austria, which was published in the October 15, 1996 issue of Cancer Research goes a long way towards explaining these peculiarities. There is some recent evidence suggesting that in HCL there is a deficiency in growth factors (cytokines) for the blood-cell forming process. These factors stimulate growth and development (differentiation) of the various types of blood cells. The present report looked at this in detail in 8 patients with HCL, finding a severe deficiency in production of all the cytokines measured - granulocyte and granulocyte-macrophage colony stimulating factors (G-CSF and GM-CSF), interleukins -3 and -6 (IL-3 and IL-6), and tumor necrosis factor alpha. Levels of these factors, especially of IL-6, increased when blood samples were enriched with monocytes. Interferon alpha increased both the intracellular levels and the secretion of IL-6 by HCL cells, as well as by blood mononuclear cells from the HCL patients but not from normal subjects. (Schwarzmeier, Cancer Res 56:4679, 1996)