Relationship of histochemically detectable altered hepatocyte foci to hepatic tumorigenesis

Conference · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5660855

Peraino, C; Staffeldt, E F; Carnes, B A; Ludeman, V A; Blomquist, J A; Vesselinovitch, S D

A new experimental system was used to examine the stages of chemically induced hepatic neoplasia in the rat. The treatment protocol involved the intraperitoneal injection of a single nonnecrogenic dose of carcinogen (diethylnitrosamine (DEN) or benzo(a)pyrene (BAP)) into male and female rats within one day after birth, followed by dietary exposure to promotor (0.05% dietary phenobarbital) beginning at weaning. Rat livers were examined for tumors and for foci of altered hepatocytes using six histochemical markers. Foci containing between one and six markers were identified and their average sizes were calculated. The same complement of histochemical tests was applied to the primary hepatic tumors observed in this study. The data showed that (1) The new treatment protocol was highly efficient for foci and tumor production. (2) Foci growth rates and incidence levels were directly related to hepatocarcinogenic effectiveness (DEN > BAP), whereas both carcinogens had similar effects on foci phenotypic properties. (3) After their formation, foci at a given level of phenotypic complexity did not become progressively more complex. (4) Foci incidence levels were sex dependent (females > males) but foci growth rates were the same for both sexes. (5) Foci growth rates and growth capacities were directly related to foci phenotypic complexity levels. (6) Foci frequencies and phenotypic complexities were inversely related; the reverse was true for tumors, although 10% of the tumors were relatively simple (3 markers or less). (7) Marker frequency distribution patterns were completely different in foci and tumors. From these observations we suggest that the foci are manifestations of the carcinogenic stimulus on control of cell division and phenotypic character.

• Research Organization: Argonne National Lab., IL (USA); Chicago Univ., IL (USA). Dept. of Radiology
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5660855
• Report Number(s): CONF-8305135-1; ON: DE84000570
• Country of Publication: United States
• Language: English

Related Subjects

550300 -- Cytology
560305* -- Chemicals Metabolism & Toxicology-- Vertebrates-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
AROMATICS
BENZOPYRENE
BODY
CARCINOGENESIS
CONDENSED AROMATICS
DIGESTIVE SYSTEM
DISEASES
GLANDS
HISTOLOGICAL TECHNIQUES
HISTOLOGY
HYDROCARBONS
LIVER
MAMMALS
NEOPLASMS
NITROSO COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PATHOGENESIS
PROMOTERS
RATS
RODENTS
TUMOR PROMOTERS
VERTEBRATES