High tumorigenicity in SP cells.

<p>A, Table presentation of the tumorigenic potential of H460 SP and non-SP cells. Three parameters of tumorigenicity, i.e., tumor incidence, latency, and volume (*<i>P</i><0.01) were shown. All animals were terminated (term.) 28 days after implantation. B, The SP cells regenerated larger tumors than corresponding non-SP cells at every cell dose. C, Gross tumor images when tumors were harvested at day 28 after s.c. injection of the SP and non-SP cells into NOD/SCID mice. D, Representative HE-stained photomicrographs of SP and non-SP tumors.