Butyrate rapidly induces growth inhibition and differentiation in HT-29 cells.
Selected G1 events associated with butyrate-induced differentiation were examined in HT-29 colon adenocarcinoma cells. [3H]Thymidine incorporation by HT-29 cells was decreased to 40% of control levels by treatment with 5 mM butyrate for 24 h, and cell numbers decreased to 21% of control levels after 48 h of treatment. Cells released from butyrate arrest entered S phase approximately 24 h after release, and serum-deprived HT-29 cells escaped growth inhibition if butyrate was added 8 h or more after serum restimulation. Northern analysis of RNA isolated from rapidly growing HT-29 cells showed a marked induction of alkaline phosphatase mRNA expression within 12 h of treatment with 5 mM butyrate. The appearance of alkaline phosphatase mRNA was temporally associated with a 5-fold increase in expression of transforming growth factor beta 1 (TGF-beta 1) mRNA. Expression of the nuclear protooncogene c-myc began to decrease 30 min after treatment with butyrate and was decreased 4.5-fold 4 h after treatment; however, expression of other immediate-early genes (nup/475 and zif/268) was not significantly affected. Histochemical staining of HT-29 monolayers showed that no cells were positive for alkaline phosphatase protein prior to treatment, and 90% were positive 48 h after treatment. TGF-beta 1 and TGF-beta 2 had no effect on HT-29 cell growth. TGF-beta 1 did not induce alkaline phosphatase mRNA or histochemical positivity. These data indicate that butyrate arrests HT-29 cell growth early in G1.(ABSTRACT TRUNCATED AT 250 WORDS)
Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-2576.
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Barnard
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Warwick
D000230:Adenocarcinoma / Q000473:pathology; D000469:Alkaline Phosphatase / Q000096:biosynthesis / Q000235:genetics; D002087:Butyrates / Q000494:pharmacology*; D020148:Butyric Acid; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D003110:Colonic Neoplasms / Q000473:pathology; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D051766:Early Growth Response Protein 1; D004848:Epithelium / Q000187:drug effects / Q000473:pathology; D005634:Fructose-Bisphosphate Aldolase / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D017874:Immediate-Early Proteins; D007399:Interphase / Q000187:drug effects; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000473:pathology; D009363:Neoplasm Proteins / Q000096:biosynthesis; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics; D016271:Proto-Oncogene Proteins c-myc / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D012334:RNA, Neoplasm / Q000096:biosynthesis; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000235:genetics; D051816:Tristetraprolin; D014407:Tumor Cells, Cultured
D002087:Butyrates; D004268:DNA-Binding Proteins; C497325:EGR1 protein, human; D051766:Early Growth Response Protein 1; D017874:Immediate-Early Proteins; D009363:Neoplasm Proteins; D011506:Proteins; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D014157:Transcription Factors; D016212:Transforming Growth Factor beta; D051816:Tristetraprolin; C497552:ZFP36 protein, human; D020148:Butyric Acid; D000469:Alkaline Phosphatase; D005634:Fructose-Bisphosphate Aldolase