DNA damage in the urinary bladder epithelium of male F344 rat was tested by alkaline elution assay after an intravesical injection of o-phenylphenol (OPP) or its non-conjugated urinary metabolites. DNA damage, as represented by an increase of the elution rate constant, was induced by the injection of 2-phenyl-1, 4-benzoquinone (PBQ) at the concentration of 0.05-0.1%, but was not observed after the injection of either OPP or 2, 5-dihydroxybiphenyl at 0.05%. Histopathologically, a single intravesical injection of 0.05% or 0.1% PBQ was shown to induce epithelial hyperplasia of he bladder epithelium on day 5 after the treatment.

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A unique T-cell line, designated ATL-5T, was established from lymphoma cells in pericardial effusion of an adult T-cell leukemia (ATL) patient not carrying HTLV-1 provirus. The cell line is OKT4 and/or Leu3a⁺ and OKT8 and/or Leu2a⁺, but interleukin 2 receptor (IL2R)^- and HTLV-1 provirus genome negative, and has cytogenetically abnormal karyotypes. The cell line contains rearranged T-cell receptor β-chain gene, which was identical in rearrangement pattern to the T-cell receptor β-chain gene in primary cells. These results suggest that factors other than HTLV-1 may sometimes be associated with HTLV-1-negative ATL. The ATL-5T cell line we describe here is unique, and should contribute to further elucidation of the mechanisms involved in the pathogenesis of HTLV-1-negative ATL and HTLV-1-positive ATL.

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Two transforming sequences in human hapatomas were detected by means of a tumorigenicity assay in nude mice using transfected NIH3T3 cells. Through hybridization with known oncogene probes, the transforming gene in one hepatoma was found to be the human hst gene. The transforming sequence in the other hepatoma showed no sequence homology with any of the oncogenes examined.

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We detected constitutive expression of the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene in 3 human solid tumors by Northern blot analysis. Two of them were also found to secrete the GM-CSF protein by colony forming unit-culture assay. Southern blot analysis of each tumor DNA showed no gross rearrangement of the GM-CSF gene. This is the first report that demonstrates expression of the GM-CSF gene in solid tumors at the mRNA level.

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A new cell line, designated EC-GI, was established from a 65-year-old patient with esophageal carcinoma who developed humoral hypercalcemia. The original tumor as well as the cell line caused marked hypercalcemia in tumor-bearing nude mice, in which a marked increase in osteoclastic bone resorption was demonstrated. The conditioned medium of EC-GI cells contained potent bone resorbing activity which stimulated cyclic AMP production in parathyroid hormone (PTH)-responsive osteoblast-like cells (ROS 17/2.8). EC-GI cells will be useful for characterization and purification of the PTH-like factor responsible for humoral hypercalcemia of malignancy.

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Serum carotenoids concentrations in healthy inhabitants, aged 40-79 years, of a community were measured. The results are as follows. 1. The α- and β-carotene and lycopene levels in serum were significantly higher in females than males. The α- and β-carotene concentrations tended to increase with advancing age, this being especially marked for serum β-carotene levels in males. However, β-carotene levels were high in females throughout the age range of 50-69 years. There was no significant change in serum level of lycopene with age. 2. There was no significant difference in intake frequency of foods containing large amounts of carotenoids among the groups with or without smoking and drinking, as serum α- and β-carotene levels were closely associated with intake frequency of green-yellow vegetables. 3. Regular alcohol drinkers or current smokers showed lower serum β-carotene concentrations, and the effect of alcohol drinking on serum carotene level seemed to be larger than that of smoking. A synergistic lowering action of smoking and drinking on serum β-carotene level was suggested. Among the alcohol drinkers, the more cigarettes consumed per day, the lower the serum β-carotene level was, but this was not the case among the non-drinkers. Ex-smokers showed intermediate values between current smokers and non-smokers. The results suggest that alcohol drinking and smoking habit might be associated with lower serum β-carotene level, which in turn may be related to excess incidence of cancer among smokers or drinkers.

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The urine of mice injected intraperitoneally with pyrene during exposure to NO₂ was found to contain highly mutagenic compounds by means of the Ames test using Salmonella typhimurium strain TA98. The mice were exposed to 20ppm NO₂ for 3 days before intraperitoneal injection of pyrene (800mg/kg of body weight). The pyrene-treated mice were further exposed to NO₂ for an additional 24hr, and the urine from the mice was collected in ice-cooled containers and stored frozen in the dark. The collected samples were treated with β-glucuronidase and passed through activated Sep-Pack C₁₈ cartridges. After elution with methanol, the effluent was concentrated and the residue was dissolved in dimethyl sulfoxide (DMSO). The DMSO solution was fractionated by high-performance liquid chromatography and the mutagenicity of each fraction was assayed with S. typhimurium strain TA98. The mutagenic compounds 3-hydroxy-1-nitropyrene, 6-hydroxy-1-nitropyrene, 8-hydroxy-1-nitropyrene, and 1-hydroxypyrene were identified in the mutagenic fractions by mass spectrometry and UV-visible spectrophotometry with synthetic reference substances. These mutagenic compounds may have been formed by either nitration of hydroxylated pyrene, or hydroxylation of 1-nitropyrene, which is formed in vivo from pyrene and NO₂, or the simultaneous occurrence of these two reactions in the mouse body.

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The effect of castration on the development of thyroid tumors was studied histologically and biochemically in Wistar rats given a single ip injection of 210mg of N-bis(2-hydroxypropyl)-nitrosamine (DHPN) followed by phenobarbital (Pb). Castration was performed one week after, or one week before the injection of DHPN. The injection of DHPN was given at the end of the first week, and the rats were fed 500ppm Pb in the basal diet for 38 weeks from week 3 to week 40. The incidence of thyroid adenomas and cancers was 20% (4/20) and 10% (2/20) in rats treated with DHPN alone. It was 75% (15/20) and 40% (8/20) in rats treated with DHPN and Pb; 30% (6/20) and 15% (3/20) in rats treated with DHPN and Pb, and castrated after DHPN; 20% (4/20) and 0% in rats treated with DHPN and Pb, and castrated before DHPN and Pb; and 0% and 0% in rats castrated either before or after receiving DHPN. Castration thus inhibited the development of thyroid tumor in rats treated with DHPN. The inhibition of tumor development in rats treated with DHPN and Pb, and castrated before receiving DHPN, was greater than in the rats castrated after receiving DHPN. Castration inhibited the secretion of TSH in rats treated with DHPN and Pb.

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F344 rats were given five mutagenic and carcinogenic heterocyclic amines, i.e., 3-amino-1, 4-dimethyl-5H-pyrido[4, 3-b]indole (Trp-P-1), 3-amino-1-methyl-5H-pyrido[4, 3-b]indole (Trp-P-2), 2-aminodipyrido[1, 2-α:3', 2'-d]imidazole (Glu-P-2), 2-amino-9H-pyrido[2, 3-b]indole (AαC), and 2-amino-3-methylimidazo[4, 5-f]quinoline (IQ), mixed together in the diet each at one-fifth of the concentration used in the previous single-compound carcinogenesis experiment. Liver, colon and Zymbal gland tumors in both sexes, skin tumors in males and clitoral gland tumors in females were induced at significantly higher incidences than in control groups. Among them, the incidences of liver tumors in both sexes, skin tumors in males and clitoral gland tumors in females were significantly higher than those expected from the simple assumptions that the incidence of tumors induced by each compound would be one-fifth of that in the corresponding previous experiment and that the combined effect of the five chemicals would be additive.

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Urinary bladders that appeared normal macroscopically were obtained from 313 autopsy cases of both sexes and examined microscopically. Proliferative lesions such as Brunn's nests and cystitis glandularis were frequent in cases of all ages and both sexes. Metaplastic lesions such as columnar or cuboidal metaplasia and squamous metaplasia were less frequent. These two types of lesions were not related to age, but squamous metaplasia was more common in females than in males. The sites of predilection for these 4 types of lesions were the trigone and anterior wall. Hyperplasia was observed in 16.3% of the male and 10.6% of the female cases, and dysplasia in 6.8% of the male and 5.7% of the female cases. Both types of lesions were more frequent in older than younger cases. Neither type of lesions was related to chronic inflammation. One case of carcinoma in situ was found in a male. These data and mapping of the bladders indicated that none of these benign proliferative and metaplastic lesions were related with the development of dysplasia or carcinoma in situ.

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Tissues from 52 cervical carcinomas, 15 cervical intraepithelial neoplasias III (CINs III), and 3 vulvar carcinomas were examined for the presence of human papillomavirus (HPV) sequences by Southern blot hybridization with HPV 16 or 18 DNA as the probe. HPV 16 or 18 DNA was detected in only 17 cervical carcinomas (33%), 5 CINs III (33%), and 1 vulvar carcinoma (33%). These frequencies are lower than those reported by others. However, new, as yet unidentified, HPVs were also detected at rather high frequency under less stringent conditions of hybridization using HPV 16 and 18 DNAs as probes. These HPVs did not hybridize with HPV 6, 11, 16 or 18 under stringent conditions, and were different from two other known types of genital tumor-associated HPVs, HPV 31 and HPV 33, judging from the patterns of their restriction enzyme digests. The total frequencies of HPV sequences were 48% (25/52) for cervical carcinomas, 53% (8/15) for CINs III, and 67% (2/3) for vulvar carcinomas.

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Applications of the vector diagram, a new type of representation of protein structure, in homology search of various proteins including oncogene products are presented. The method takes account of various kinds of information concerning the properties of amino acids, such as Chou and Fasman's probability data. The method can detect conformational similarities of proteins which may not be detected by the conventional programs.

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The molecular mechanism of acquisition of resistance to 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) was investigated using ACNU-resistant clones (ACNU^r-1-4) isolated from the V79 cell line. The binding level of alkyl cyanate, a decomposition product of ACNU, to protein in ACNU^r-1 cells was not less than that in the parental V79 cells, indicating that the acquired resistance was not due to a reduced intracellular concentration of ACNU. Because O⁶-chloroethylguanine, an intermediate in cytotoxic interstrand cross-link formation by ACNU, is known to be repaired by the same mechanism as O⁶-ethyldeoxyguanosine (O⁶-EtdGuo), we quantitated O⁶-EtdGuo by radioimmunoassay at various times after exposure of cells to 100μg/ml N-ethyl-N-nitrosourea for 20min. In V79 cells, elimination of O⁶-EtdGuo was negligible, but in all four resistant clones, 30 to 59% of the O⁶-EtdGuo was removed within 24hr after exposure. This increased removal of O⁶-EtdGuo among the resistant clones was associated with the activity of O⁶-alkylguanine DNA alkyltransferase (O⁶-AGT) determined using cell extracts. The present results indicate that increased removal of O⁶-chloroethylguanine in ACNU-resistant clones by O⁶-AGT is mechanistically linked to the acquisition of resistance to ACNU.

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Neuron-specific γγ enolase was purified from a neuroblastoma tissue obtained at surgical resection. The final preparation showed a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with a mobility identical to that of γγ enolase purified from human brain. The values of specific activity (about 80units/mg), optimal pH (6.9), and K_m for 2-phosphoglycerate (about 3×10^-5M) of γγ enolase purified from neuroblastoma were very similar to those of γγ enolase purified from brain. The results of peptide mapping analysis after limited proteolysis, and amino acid analysis also indicate there was no difference between the enzymes purified from neuroblastoma and brain.

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The transplantable mouse mammary tumor, TPDMT-4, is pregnancy-dependent and requires prolactin (PRL), estradiol (E₂) and progesterone (Pg) for growth. To examine the role of PRL in regulating tissue growth and the levels of estrogen receptor (ER) and progesterone receptor (PgR), tumor-bearing mice were ovariectomized, hysterectomized and then injected with ergocornine hydrogenmaleate (ERG), ERG+PRL, or ERG+PRL+E₂+ Pg. Total (nuclear+cytoplasmic) ER and PgR in normal and neoplastic mammary tissues were measured. In addition, tumor size and tritium-labeled thymidine ([³H]dThd) incorporation into nuclei of the tumor and mammary gland were determined. PRL alone caused a 2- to 3-fold increase in ER and PgR levels in normal mammary gland but not in the tumor. PRL alone caused a modest increase in the number of ³H-thymidine-labeled nuclei in both tissues. PRL combined with E₂ and Pg increased the percent of labeled nuclei 5- to 10-fold in both tissues, and increased the PgR levels in normal but not in tumor tissue. Thus, PRL alone can increase ER in normal mammary tissue but this increase is not required for growth since ER levels are unchanged when PRL+E₂+Pg are injected and mammary cell growth is stimulated. The ability of PRL to up-regulate ER has been lost in the tumor. Since basal levels of ER and PgR are not altered in the tumor when PRL+E₂+Pg are given, an increase in ER and PgR levels is not required for the three hormones to stimulate tumor growth.

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Gangliosides (GM3, GD3, GM2, gangliotetraose-series gangliosides) and their asialo derivatives of several adult T-cell leukemia (ATL) cell lines (ATL-1K, ATL-3I, ATL-5S and MT-2 cells) and the lymphocytes from a patient with ATL were quantified by highly sensitive enzyme-immunostaining on silica gel thin layer chromatograms using specific antiglycolipid antibodies. GM2 and GD3 gangliosides and asialo GM1 (GA1) newly appeared in all cultured ATL cells and the lymphocytes from patients with ATL but not in normal human T-lymphocyte-rich fraction. Gangliotetraose-series gangliosides, GM1a, GD1a and GD1b, were also found in cultured ATL cells, but were not detected in normal human lymphocytes or the lymphocytes of a patient with ATL. Quantitative immunostaining analysis of GM2, GD3 gangliosides and GA1 in T-cell lines from non ATL leukemia (Molt-3, CEM and Jurkat) revealed GM2 gangliosides in all the T-cells from non ATL tested and GA1 in Jurkat cells, but no GD3 ganglioside was found in the non ATL leukemia cells tested. The above results indicate that ganglioside GD3 may be a T-cell glycosphingolipid antigen associated with ATL, and ganglioside GM2 and GA1 may be useful as surface markers related with ATL, as well as T-cell lymphoma. The contents of GA1, GM3, GD3, GM2 and gangliotetraose-series gangliosides in ATL cells were all different, even though all the cells used have a common antigen reactive with monoclonal OKT-4 antibody, indicating that there are several subsets of human inducer/helper T-cells, which possess different metabolism and expression of gangliosides.

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The mechanisms of action of a novel macromolecular antitumor antibiotic (SN-07) were examined using cultured mouse lymphoid leukemia L1210 cells. A shoulder exponential-type cytotoxicity was observed when the cells were treated with 3.13 to 100ng/ml SN-07 for 1hr and surviving colonies were counted after a 14-day incubation. It was found that 500ng/ml SN-07 inhibited both RNA and DNA syntheses significantly at 40 and 80min, respectively, while 8, 000ng/ml did not affect protein synthesis at 80min. Treatment with a low concentration (80ng/ml) of SN-07 for 1hr inhibited both RNA and DNA syntheses after a 24-hr post-incubation. The alkaline elution technique revealed that 8, 000ng/ml SN-07 induced DNA interstrand cross-links time-dependently for 1 to 4hr, and a 1-hr treatment with 80 to 8, 000ng/ml SN-07 induced DNA breaks after a 24-hr post-incubation. According to flow cytometric analysis, most L1210 cells progressed to the G2 phase in the cell cycle at a cytostatic concentration (25ng/ml) of SN-07, and typical inhibition of the cell cycle progression was observed at a cytocidal concentration (200ng/ml).

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The radiosensitizing effects and hypoxic cytotoxicity of 2-(4'-hydroxybenzylidene)-cyclopentene-1, 3-dione (KIH-200) and its 3'-methoxy and 3', 5'-dimethoxy derivatives (KIH-201 and KIH-202) were investigated in vitro. These synthetic compounds were newly designed as non-nitro electron-affinic radiosensitizers and hypoxic cytotoxins on the basis of their high electron affinities and electrostatic potentials which were estimated by semiempirical molecular orbital calculation using the CNDO/2 program. The compounds were shown to have weak but apparent hypoxic cytotoxicity to FM3A cells from C3H mice. On irradiation in the presence of KIH-201 or KIH-202, hypoxic cells were more sensitive than aerobic cells at very low drug concentrations (below 10μM), whereas KIH-200 was less effective.

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