Tumorigenic 3T3 cells maintain an alkaline intracellular pH under physiological conditions - PubMed (original) (raw)

Tumorigenic 3T3 cells maintain an alkaline intracellular pH under physiological conditions

R J Gillies et al. Proc Natl Acad Sci U S A. 1990 Oct.

Abstract

One of the earliest events in the response of mammalian cells to mitogens is activation of Na+/H+ exchange, which increases intracellular pH (pHin) in the absence of HCO3- or at external pH values below 7.2. The proliferative response can be blocked by preventing the pHin increase; yet, the proliferative response cannot be stimulated by artificially raising pHin with weak bases or high medium pH. These observations support the hypothesis that optimal pHin is a necessary, but not sufficient, component of the proliferative-response sequence. This hypothesis has recently been challenged by the observation that transfection of NIH 3T3 cells with yeast H(+)-ATPase renders them tumorigenic. Although previous measurements indicated that these transfected cells maintain a higher pHin in the absence of HCO3-, whether H(+)-ATPase transfection raised the pHin under physiologically relevant conditions was not known. The current report shows that these transfected cells do maintain a higher pHin than control cells in the presence of HCO3-, supporting the possibility that elevated pHin is a proliferative trigger in situ. We also show that these cells are serum-independent for growth and that they glycolyze much more rapidly than phenotypically normal cells.

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References

    1. Proc Natl Acad Sci U S A. 1978 Jul;75(7):3327-31 - PubMed
    1. Mol Cell Biol. 1990 Aug;10(8):4110-5 - PubMed
    1. J Membr Biol. 1981;61(3):143-53 - PubMed
    1. Proc Natl Acad Sci U S A. 1982 Dec;79(24):7778-82 - PubMed
    1. J Cell Physiol. 1985 Feb;122(2):178-86 - PubMed

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