Tissue ferritin concentration and prognosis in carcinoma of the breast.

Seven year follow-up data were available on 36 of 40 breast carcinoma patients in whom breast tissue ferritin concentrations at the time of surgery were known. 18 patients were alive and free of recurrence or second tumor (Group 1) and 11 died with breast cancer (Group 2). Patients with lower tissue ferritin concentrations defined as less than 319 ng/mcp (nanograms of ferritin/milligram of cytosol protein) were at reduced risk: 86% of patients with low tissue ferritin concentration survived free of recurrence or second tumor vs. 40% of patients with high tissue ferritin concentration (P = 0.0056). Mean breast carcinoma tissue ferritin concentration was 295 +/- 52 ng/mcp in Group 1 and 444 +/- 55 ng/mcp in Group 2 (P = 0.036). Lymph node involvement was predictive of mortality from breast carcinoma (P = 0.0003), but did not correlate with mean tissue ferritin concentration (P = 0.082). 10/10 (100%) patients who had both low tissue ferritin concentration and absence of lymph node involvement were in Group 1. The correlation of breast tissue ferritin concentration with histopathologic dedifferentiation and with prognosis suggests tumor tissue ferritin as a marker of malignant potential.

Tissue ferritin concentration in carcinoma of the breast.

Ferritin concentration was measured in cytosol extracts of 44 mammary carcinomas and 14 benign breast tissues. A six-fold difference was observed (mean, 364.6 +/- 223.3 ng/mcp in malignant tissue versus mean, 60.2 +/- 42.1 ng/mcp in benign tissue P less than 0.001). Thirty-five malignant tissue specimens were reviewed independently by a pathologist without knowledge of their ferritin contents. Higher concentrations of ferritin were present in malignancies with greater degrees of epithelial proliferation and plemorphism suggesting the malignant epithelium as the major site of the increased ferritin. There was no correlation between desmoplastic reaction within the tumors or inflammation within or adjacent to the tumors and ferritin concentration. Ferritin in breast tissue may be important as a marker of neoplasia, a source of elevated serum ferritin, an indicator of clinical prognosis or an immunosuppressive substance.

DNA-dependent RNA polymerases from Artemia salina: decreasing polymerase activities and number of polymerase II molecules in developing larvae.

Embryos and larvae of the brine shrimp, Artemia salina, provide a useful biological system for biochemical studies of animal development. Dormant encysted embryos can be cultured readily in the laboratory to provide large quantities of free-swimming nauplius larvae. The rate of synthesis of all classes of RNA in swimming larvae declines markedly between 24 and 72 h after immersion of dormant embryos in sea water. Nuclei were isolated from 24-72 h larvae and RNA polymerase activity was measured under conditions in which the nuclei remained intact. Total RNA polymerase activity of isolated nuclei decreased in parallel with RNA synthesis in vivo. RNA polymerases were solubilized from nuclei and fractionated by chromatography on DEAE-cellulose. The levels of both RNA polymerases I and II also decreased in parallel with RNA synthesis in vivo. The specific activity of highly purified RNA polymerase II was determined by comparison of enzyme activity with the mass of RNA polymerase II subunits displayed on SDS gels. The specific activities of RNA polymerase II preparations from 24 and 72 h larvae were identical. The number of polymerase II molecules was estimated from the mass of the subunits. The number of molecules per nucleus declined from 20,000 at 24 h to 3500 at 72 h.