Mutagenesis and repair by low doses of alpha radiation in mammalian cells.

Low doses of alpha radiation in basements have been causally implicated in lung cancer. Previous studies have concentrated on high dose effects, for which no significant repair was found. In the present study, the methodology for measuring mutation by quantitating mitotic breaks and gaps was found to be applicable to G2-phase Chinese hamster ovary cells irradiated with 10-50 cGy of alpha radiation.

Cyclic AMP and the reverse transformation reaction.

Traditional methods for cancer treatment have been aimed at killing the cancer cells. Unfortunately this approach all too often is accompanied by harmful killing of normal cells. The present paper describes an experimental program in our laboratory in which cancer cells are treated so as to revert to normal cell behavior.

Bradykinin antagonist dimer, CU201, inhibits the growth of human lung cancer cell lines by a "biased agonist" mechanism.

All small cell (SCLCs) and many non-small cell lung cancers (NSCLCs) have neuroendocrine features including production of neuropeptides and cell surface receptors creating autocrine and paracrine growth loops. Neuropeptides bind to a family of 7-transmembrane receptors and activate heterotrimeric G proteins consisting of G(alphaq) and G(alpha12,13). Substance P derivatives (SPDs) induced apoptosis and inhibited growth of lung cancer cells by discoordinately inhibiting G(alphaq) and stimulating G(alpha12,13).

Mutation inhibition by beta-estradiol after low doses of gamma-irradiation of mammalian cells.

The methodology previously described for measuring mutagenesis has been applied to the study of mutation prevention in immortalized G2 phase human lymphocytes exposed to 25 and 50 cGy of gamma-radiation. Caffeine prevents repair of mutations. Two times 10(-4) M beta-estradiol applied for 2.

Genome exposure and regulation in mammalian cells.

A method of measurement of exposed DNA (i.e. hypersensitive to DNase I hydrolysis) as opposed to sequestered (hydrolysis resistant) DNA in isolated nuclei of mammalian cells is described.