Patent ID: 7947275

Claim:
An in vitro assay method for detecting cancer cell growth stimulation by a substance of interest, the method comprising: maintaining a predetermined population of steroid hormone-responsive mucosal epithelial cancer cells in a steroid hormone-free nutrient medium comprising a basal nutrient fluid devoid of unbound Fe (III) and comprising calcium ions and an amount of at least one immunoglobulin chosen from the group consisting of non-monomeric plasma IgA and polymeric IgM sufficient to inhibit cell growth in the absence of an inhibition-reversing amount of a steroid hormone, said cells also being steroid hormone dependent for proliferation in vivo when implanted into a suitable host; adding said substance of interest to said cells and nutrient medium to yield a test mixture; incubating said test mixture for a predetermined period of time under cell growth promoting conditions; and determining the cell population in said test mixture after said predetermined period of time, a measurable increase in said cell population indicating a cancer cell growth stimulating effect by said substance of interest.