Polyamines in rapid growth and cancer

Role of Polyamines in the Control of Cell Proliferation and Differentiation

The mechanisms that initiate liver regeneration after resection of liver tissue are not known. To determine whether cytokines are involved in the initiation of liver growth, we studied the regeneration of the liver after partial hepatectomy (PH) in mice lacking type I tumor necrosis factor receptor (TNFR-I). DNA synthesis after PH was severely impaired in these animals, and the expected increases in the binding of the NF-kappaB and STAT3 transcription factors shortly after PH failed to occur. Binding of AP-1 after PH was decreased in TNFR-I knockout mice compared with animals with the intact receptor whereas C/EBP binding was not modified. Injection of interleukin 6 in TNFR-I-deficient animals 30 min before PH corrected the defect in DNA synthesis and restored STAT3 and AP-1 binding to normal levels but had no effect on NF-kappaB binding in the regenerating liver. The results indicate that TNF, signaling through the TNFR-I, can initiate liver regeneration and acts by activating an interleukin 6-dependent pathway that involves the STAT3 transcription factor.

https://www.pnas.org/content/pnas/94/4/1441.full.pdf

Initiation of liver growth by tumor necrosis factor: Deficient liver regeneration in mice lacking type I tumor necrosis factor receptor

The role of hepatocytes and oval cells in liver regeneration and repopulation.

The residual structural framework of the cell nucleus termed the nuclear protein matrix, is associated with newly synthesized DNA in regenerating rat liver. One minute after rats are injected with [3-H] thymidine, more than 90 percent of the total tritium in nuclear DNA is associated with the matrix DNA although this DNA comprises only 25 percent of the total nuclear DNA. In contrast, the bulk DNA, 75 percent of total nuclear DNA, contains less than 8 percent of the total labeled DNA. The percentage of total labeled DNA associated with the bulk DNA increases for 30 minutes after injection and decreases correspondingly in the matrix DNA.

https://science.sciencemag.org/content/sci/189/4199/291.full.pdf

Nuclear Protein Matrix: Association with Newly Synthesized DNA

Ornithine decarboxylase activity in relation to growth of rat liver: Effects of partial hepatectomy, hypertonic infusions, celite injection or other stressful procedures

Summary The rise in hepatic DNA synthesis in response to partial hepatectomy was accelerated in rats subjected to surgery 4.5 to 8 hr or 3 days before hepatectomy. Bovine growth hormone, in doses from 0.03 to 2.0 mg, also accelerated the response to hepatectomy, but cortisone, hydrocortisone, and adrenocorticotropic hormone were ineffective. Neither surgery nor growth hormone stimulated DNA synthesis significantly in the livers of nonhepatectomized rats.

https://cancerres.aacrjournals.org/content/canres/30/9/2353.full.pdf

Nancy J. Oakman

Papers

Ornithine decarboxylase activity in relation to growth of rat liver: Effects of partial hepatectomy, hypertonic infusions, celite injection or other stressful procedures

Accelerated Response of Hepatic DNA Synthesis to Partial Hepatectomy in Rats Pretreated with Growth Hormone or Surgical Stress

Thymidine triphosphate content of regenerating rat liver.