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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1984-3-15
pubmed:abstractText
Hydrocortisone (HC) reduced the macrophage content of four murine tumors to less than half of control values. Since HC causes monocytopenia and inhibits the recruitment of mononuclear phagocytes at sites of inflammation but does not affect the viability and proliferative capacity of macrophages, this finding suggests that the maintenance of macrophage levels in growing tumors is in part dependent upon the entry into the neoplasm of circulating monocytes. HC inhibited the growth of these tumors. The effect of HC was most marked on the mFS6 and MN/MCA1 sarcomas and 3LL carcinoma, with only marginal inhibition in the M109 carcinoma. HC augmented spontaneous and/or artificial (i.v.) metastasis in these tumor models. Cells from metastatic foci of the mFS6 sarcoma and M109 carcinoma inoculated i.m. were as susceptible to HC as cells from primary tumors. The effects of HC on macrophage content, growth and metastasis of the M109 carcinoma and mFS6 sarcoma were similar in mice with defective T-cell function (nude or thymectomized) or defective NK activity (beige or antiasialo GM1-treated) and in controls. The in vitro growth of the mFS6 and MN/MCA1 sarcomas was not modified by HC. Some inhibition of tumor-cell proliferative capacity was observed with the 3LL and M109 tumors. Tumor cell had high-affinity binding sites for glucocorticoid hormones, but these were not correlated to susceptibility in vivo. Thus it is unlikely that a direct interaction of HC with tumor cells accounts for the inhibition of tumor growth observed in vivo. To evaluate whether HC affected tumor growth by reducing the macrophage content of tumors, mFS6 sarcoma cells were transplanted, mixed with peritoneal macrophages into normal or HC-treated mice. Macrophages did not affect the growth of tumor cells in normal mice, whereas in HC-treated animals lesions from mixtures of macrophages and sarcoma cells appeared earlier and weighed more than those from tumor cells alone or tumor cells and thymocytes. However, macrophages did not reconstitute growth of the other sarcoma (MN/MCA1) in HC-treated mice. These results are consistent with the hypothesis that HC inhibited growth of some poorly immunogenic transplanted murine tumors, at least in part, by interfering with the macrophage levels in neoplastic tissues, tumor-associated macrophages providing the conditions for optimal tumor-cell proliferation at least in some neoplasms.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0020-7136
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
95-105
pubmed:dateRevised
2007-7-24
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Effect of hydrocortisone on the macrophage content, growth and metastasis of transplanted murine tumors.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't