Citrate metabolism of normal and malignant prostate epithelial cells.

T o introduce the subject of this review, we offer the following anecdotal experience. Recently, one of us (L.C.C.) was invited to present a seminar on “prostate citrate metabolism” to a clinical group of urologists, pathologists, and oncologists. I opened the presentation with the question, “Tell me what the major function of the prostate gland in humans is?” It was evident from the response that this was a perplexing question and that no consensus existed regarding the function of the prostate. Finally, I stated that, in our view, the major function of the human prostate gland was to produce and secrete citrate, and that we would provide compelling evidence to support that view. In much the same way, we now ask you, the reader, the same question; and we offer the same view, which this review will establish. The normal human prostate gland, as well as that of many other animals, has the function of producing, accumulating, and ultimately secreting extraordinarily high levels of citrate (Table I>. The glandular secretory epithelial cells are responsible for this unique capability, which does not exist in any other soft tissue cells in the body. The accumulation and secretion of citrate (which we refer to as “net citrate production”) require the existence of unique metabolic relationships associated with citrate metabolism, with major consequences and implications for the intermediary energy metabolism of citrate-producing prostate epithelial cells. (For recent reviews of prostate citrate me-

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