Fibrosis in immune control of mammary-tumor growth.
In malignancies, an interruption of growth (dormancy) is sometimes observed. In the immunogenic mammary carcinoma MC2, dormancy followed by regression after a period of growth was observed in 18% of s.c. implants in normal mice. Dormant implants removed for histologic examination were invariably found to be completely surrounded by a highly fibrous stroma. Fibrosis was enhanced in immunized mice, and reduced in immuno-deficient mice. Surgical disruption of the fibrous capsule around dormant tumors early (19 +/- 3 days) in the immune response led more frequently to resumed growth, while later (32 +/- 3 days) disruption of the capsule led more frequently to complete regressions. This showed that fibrous capsules that could destroy tumors could also shield them against well-developed systemic immune mechanisms.
Vaage
J
J
Department of Experimental Pathology, Roswell Park Cancer Institute, Buffalo, NY 14263.
D000818:Animals; D002455:Cell Division; D005260:Female; D005355:Fibrosis / Q000276:immunology / Q000473:pathology; D015674:Mammary Neoplasms, Animal / Q000276:immunology / Q000473:pathology*; D051379:Mice; D008809:Mice, Inbred C3H; D008819:Mice, Nude; D008940:Mitotic Index; D009365:Neoplasm Regression, Spontaneous / Q000276:immunology / Q000473:pathology*; D009368:Neoplasm Transplantation; D014181:Transplantation Immunology