title: Comparable growth regulation of five human tumor cell lines by neonatal human lung fibroblasts in semisolid culture media.
abstract: Cellular growth interactions were studied between neonatal human lung fibroblasts (NLF-13) and human tumor lines derived from carcinomas of the prostate (PC-3, DU145), bladder (J82), and endometrium (HEC-1A) and from a glioma (Hs 683t). NLF-13 were interacted with tumor cells in soft agar or agarose media using two experimental protocols. In one system, NLF-13 cells were grown as anchored monolayers proliferating under the tumor cell layer. In the second, NLF-13 were embedded directly (nonanchored) into the agar or agarose layer with the tumor cells. The results from both interaction systems were similar for all five tumor lines. Anchored NLF-13 caused a dose-dependent inhibition of tumor growth, whereas nonanchored cells produced a dose-dependent growth stimulation. A time exposure experiment indicated that tumor stimulation and inhibition were biphasic responses to NLF-13. It was concluded that low concentrations of a diffusible NLF-13 product(s) accelerated tumor growth, whereas high concentrations were inhibitory. Further, the production of the active NLF-13 substance(s) was positively correlated with NLF-13 growth rate. Tumor cell inhibition was irreversible after a 5-day exposure to proliferating NLF-13 cells. Another line of normal neonatal human lung fibroblasts (NLF-147) showed inhibitory properties similar to those described for NLF-13. However, preliminary studies with fibroblasts from the skin of a Down's syndrome neonate (DS-172) and from a human kidney tumor (KTF-130) have shown both these fibroblast types to have a reduced ability to inhibit tumor cell cultures (J82) compared to the neonatal lung fibroblasts (NLF-13 and NLF-147).
mesh_terms: D000362:Agar; D002450:Cell Communication; D002455:Cell Division; D002460:Cell Line; D005260:Female; D005347:Fibroblasts / Q000166:cytology; D005910:Glioma / Q000473:pathology*; D006801:Humans; D007231:Infant, Newborn; D007700:Kinetics; D008168:Lung / Q000166:cytology*; D008297:Male; D011471:Prostatic Neoplasms / Q000473:pathology*; D001749:Urinary Bladder Neoplasms / Q000473:pathology*; D014594:Uterine Neoplasms / Q000473:pathology*
chemical_list: D000362:Agar