Inhibitory effects of phytohemagglutinin on growth of leukemia lymphoblasts L5178Y in vitro and in vivo.
Phytohemagglutinin (PHA) inhibited the growth of mouse leukemia lymphoblasts L5178Y in culture. RNA synthesis was repressed significantly within the first hour, and the rates of DNA and protein synthesis were significantly decreased within the second hour; maximum inhibition occurred after 24 hours. The ability of the cells to form colonies in soft agar was limited to a greater extent at much lower PHA concentrations. The cells lost their tumorigenicity in syngeneic DBA/2 mice after 4 hours of PHA treatment, when the viability was not appreciably decreased. The cultures of a PHA-resistant strain derived from a resistant colony cloned from the PHA-containing soft agar plate showed increased resistance toward PHA. A fourfold increase in PHA concentration was needed for the same rate of inhibition of the original cell line to be attained.
D000371:Agglutination / Q000187:drug effects; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002999:Clone Cells; D004273:DNA, Neoplasm / Q000096:biosynthesis; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D005260:Female; D037102:Lectins / Q000494:pharmacology*; D007942:Leukemia, Experimental / Q000378:metabolism / Q000473:pathology*; D008214:Lymphocytes / Q000187:drug effects; D051379:Mice; D008811:Mice, Inbred DBA; D009363:Neoplasm Proteins / Q000096:biosynthesis; D012334:RNA, Neoplasm / Q000096:biosynthesis; D013997:Time Factors
D004273:DNA, Neoplasm; D037102:Lectins; D009363:Neoplasm Proteins; D012334:RNA, Neoplasm