Accumulation in “normal” lungs of live tumorigenic cells during sub‐cutaneous growth of weakly and highly metastasizing tumors and their In vitro sensitivity to growth regulation by normal fibroblasts

摘要: The main purposes of the study were: (1) in vivo comparison accumulation live tumorigenic cells (LTC) macroscopically normal lungs animals bearing 6 s.c. Syrian hamster sarcomas differing spontaneous metastasizing activity (SMA); (2) vitro examination sensitivity these cell strains to growth-regulating signals fibroblasts. Cell used differed SMA from very weak (WM) extremely high (HM). numbers LTC doses "normal" lung tissue tumor-bearing were determined transplantation tests by titrating single-cell suspensions prepared tissues 5 animals, for each strain, every days during 30 tumor growth, until appearance first metastases. WM and HM embryo fibroblasts (HEFs) was examined co-culturing with daily determination 3H-TdR incorporation grown or without contact HEFs. data presented demonstrate surprisingly similar efficiency occupation strains, disseminating spontaneously tumors; significantly lower cells, contrast WM, growth inhibition HEFs especially their marked ability usurp growth-stimulating