An SstI fragment of 2.9kb carrying all four coding exons of the human melanoma c-Ha-ras-1 oncogene could not transform mouse NIH 3T3 cells. Preparation of plasmid clones carrying the 2.9kb SstI DNA and adjacent regions and analyses of the biological activities of the clones revealed that, for transforming activity of c-Ha-ras-1, a nucleotide sequence of 0.85kb adjacent to the 2.9kb DNA in the upstream region was required.

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DNA isolated from a lymph node with metastasis from pancreatic adenocarcinoma in a Japanese male patient transformed NIH3T3 cells upon transfection by the calcium-phosphate precipitation technique. Analysis of DNA from the transformant revealed the presence of an activated human c-Ki-ras gene, which is considered to be responsible for the transformation of the NIH3T3 cells.

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Using a β-chain cDNA probe of the T-cell receptor, we detected T-cell receptor gene rearrangement in leukemic cells from an adult patient with common acute lymphocytic leukemia (cALL). The leukemic cells expressed non-T, non-B cell marker profiles (CALLA⁺, J5⁺, Leu-1^-, Leu-4^-, Ia+, B1^-, c-Igμ^- and TdT⁺). This is the first reported case of cALL with T-cell receptor gene rearrangement and/or deletion.

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Most human T-cell lymphotropic virus type I (HTLV-I)-carrying cell lines possess high susceptibility to AIDS retrovirus. This high permissiveness was clearly correlated with the amount of OKT-4 molecules, the possible receptor for AIDS retrovirus, expressed on the cell surface of HTLV-I-bearing cell lines. However, no correlation was noted in HTLV-I-negative cell lines.

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Twenty consecutive weekly sc injections of 50mg/kg body weight of 3, 2'-dimethyl-4-aminobiphenyl (DMAB), a multipotential carcinogen, were given to male F344 rats and subsequently groups of animals were treated with dietary ethinyl estradiol (EE, 2.5ppm) or methyltestosterone (MT, 300ppm) for up to 40 weeks. Prostate carcinomas were found in 4 out of 32 rats given DMAB followed by MT and in 2 out of 29 rats given DMAB alone. Atypical hyperplasia of the prostate epithelium in these two groups was found in 22% and 14%, respectively. Neither carcinoma nor atypical hyperplasia was seen in the prostate of animals given DMAB followed by EE. In other organs, tumors were frequently found in the ear duct, skin, and large intestine and less frequently in the lung, preputial glands, small intestine and liver. EE significantly suppressed tumor incidence of the ear duct and sebaceous glands while increasing the incidence of liver tumor and mesothelioma. The present data indicates DMAB to be a useful carcinogen for the induction of prostate carcinomas in rats.

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The potential initiating and promoting activities in the rat glandular stomach of the dicarbonyl compounds diacetyl (DA) and glyoxal (G), which are found in various heated foods, were studied. Administration of DA at doses of 300 to 1500mg/kg body weight and of G at doses of 150 to 400mg/kg body weight by gastric intubation to male F344 rats induced up to 100-fold increase in ornithine decarboxylase activity (formation of 195 pmol CO₂/30min/mg protein by DA and 302 pmol CO₂/30min/mg protein by G) with maxima after 16hr. These treatments also induced a more than 10-fold increase in DNA synthesis (incorporation of 11, 400 dpm of [³H]dThd/μ g DNA by DA and 15, 100dpm of [³H]dThd/μ g DNA by G) with maxima after 16hr, and induced apparent unscheduled DNA synthesis in the pyloric mucosa of the stomach within 3hr after administration. These results suggest that DA and G have potential tumor-promoting activities and may also have initiating activities in carcinogenesis in the glandular stomach.

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3-Amino-1, 4-dimethyl-5H-pyrido[4, 3-b]indole (Trp-P-1) is a mutagenic principle isolated from a tryptophan pyrolysate. When Trp-P-1 was given to male and female F344 rats at concentrations of 0.015% and 0.02%, respectively, in the diet, it induced hepatocellular carcinomas in high incidence within a year. No tumor was found in control rats.

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The dose-dependent effect of trisodium nitrilotriacetate monohydrate (Na₃• NTA• H₂O) as a promoter in 2-stage carcinogenesis in the urinary bladder of male Wistar rats was investigated. Carcinogenesis was initiated by administration of 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in the drinking water for 4 weeks, then Na₃• NTA• H₂O was given at 1%, 0.5% and 0.3% in the diet for 28 weeks, and rats were killed in week 32. The incidences and numbers of preneoplastic lesions [papillary or nodular hyperplasia (PN hyperplasia)] in rats treated with 0.3% to 1% Na₃• NTA• H₂O increased progressively with increasing concentration of Na₃• NTA• H₂O. The incidences of papillomas in rats treated with 1% and 0.5% Na₃• NTA• H₂O in the diet and the incidence of transitional cell carcinoma (TCC) of the urinary bladder in the rats treated with 1% Na₃• NTA• H₂O (P< 0.05) were significantly higher than those in rats treated with BBN only. Administration of various doses of Na₃• NTA• H₂O without BBN did not cause any histological changes (PN hyperplasia, papilloma or TCC) in the urinary bladder. These findings showed that Na₃• NTA• H₂O is a potent promoter of urinary bladder carcinogenesis initiated by BBN in rats, and that its effect is dose-dependent.

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The promoting effect of trisodium nitrilotriacetate monohydrate (Na₃NTA• H₂O) on two-stage urinary bladder carcinogenesis in F344 rats initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) at levels of 0.01 and 0.05% was investigated. Administration of 2.0%, Na₃NTA• H₂O significantly increased both the incidence and the number per 10cm of basement membrane of preneoplastic lesions and papillomas of the urinary bladder in rats pretreated with 0.05% BBN. This result shows that Na₃NTA• H₂O has weak promoting activity in urinary bladder carcinogenesis.

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The modifying effects of 17 environmental chemicals on the development of lesions in the urinary bladder of rats with unilateral ureteric ligation were investigated. Lesions were initiated by treatment of the animals with 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) for 2 weeks, and then test chemicals were given for 22 weeks. The lesions of the urinary bladder found were preneoplastic papillary or nodular hyperplasias (PN hyperplasias) and papillomas. Additions of sodium saccharin (5%), sodium o-phenylphenate (2%), butylated hydroxyanisole (2%), and sodium L-ascorbate (5%) to the diet had significant promoting effects on the incidences and numbers of PN hyperplasias and papillomas per 10cm of basement membrane of the urinary bladder in this system. Sodium erythorbate (5%), ethoxyquin (0.8%) and carbazole (0.6%) significantly increased the incidence of PN hyperplasias. N-Nitrosopyrrolidine (0.02%) did not affect the incidence or number of PN hyperplasias but increased those of papillomas. Sodium o-phenylphenate also induced PN hyperplasias in rats without BBN-initiation. Ascorbic acid, ascorbic stearate, three dihydroxyphenols, methylhydroquinone, pyrogallol, quinoline, and uric acid did not show promoting activity in this test system. Thus, 8 of 17 chemicals tested had various promoting effects on urinary bladder carcinogenesis. These results show that this test system of BBN-initiated, unilaterally ureter-ligated rats should be useful for the detection of new bladder carcinogens and promoters.

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The Salmonella/hepatocyte system was employed to determine the mutagenicity in bacteria as well as the DNA damage induced in mouse hepatocytes following exposure to heterocyclic amines. With hepatocytes from C57BL/6N mice, 3-amino-1-methyl-5H-pyrido[4, 3-b]indole (Trp-P-2) and 2-amino-3-methylimidazo[4, 5-f]quinoline (IQ) showed a clear mutagenic effect in the Salmonella, while weak mutagenic effects were observed with 3-amino-1, 4-dimethyl-5H-pyrido[4, 3-b]indole (Trp-P-1), 2-amino-6-methyldipyrido[1, 2-a:3', 2'-b]imidazole (Glu-P-1), and 2-aminodipyrido[1, 2-a: 3', 2'-d]imidazole (Glu-P-2). All the compounds induced low levels of DNA damage in the hepatocytes. In vivo pretreatment of mice with the potent monooxygenase inducer 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD; 50μg/kg) clearly increased both the mutagenicity in the bacteria and the DNA damage induced in the hepatocytes in vitro. Glu-P-2 showed the lowest mutagenic effect but induced more DNA damage at low concentrations than the other compounds when TCDD-pretreated hepatocytes were used. These data indicate that the genotoxic potency of Glu-P-2 in the intact hepatocyte differs from that observed in the bacteria. Treatment of hepatocytes with a-naphthoflavone, a selective inhibitor of polycyclic hydrocarbon-inducible cytochrome P-450 form(s), prior to exposure to the heterocyclic amines completely inhibited the mutagenic effect in the bacteria. In vivo administration of all the heterocyclic amines 4hr prior to isolating the hepatocytes resulted in DNA damage, and this effect was augmented by TCDD pretreatment of mice. Our data suggest that agents modulating the activity and composition of the cytochrome P-450 system may greatly influence both toxicity and carcinogenicity of these heterocyclic amines.

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Four hundred and sixty gastric cancer patients who had undergone operation at the National Cancer Center Hospital and an equal number of age-matched controls were analyzed in order to estimate the influence of gastric cancer family inheritance and cigarette smoking habit. Relative risks for cigarette smoking habit, for gastric cancer family inheritance and for both were 2.88, 1.67 and 4.12, respectively. Earlier age of onset of gastric cancer was observed in the gastric cancer cases with both risk factors as compared with the other patients.

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A recombinant plasmid carrying the human c-Ha-ras gene with two point mutations in codons 12 and 61 was constructed and its transforming activity on mouse NIH 3T3 cells was compared with those of genes with a single mutation in either codon 12 or 61. Quantitative analyses revealed that the gene with two mutations had essentially the same transforming activity as the genes with single mutations. These results indicate that a single mutation of the c-Ha-ras gene in either codon 12 or 61 is sufficient to activate the gene and that neither of the two mutation sites involved in activation of the gene needs to be intact for transforming activity.

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The αα form of S-100 protein (S-100a₀), which is distributed mainly in the heart and striated muscles, and also in the brain and kidney, was determined in tumor tissues and sera of patients with renal cell carcinoma by employing an enzyme immunoassay system for bovine S-100a₀ protein. The average content of S-100a₀ in the renal cell carcinoma tissue (n=10) was about 650ng/mg protein, 4-fold higher than that in the kidney (n=6, 160ng/mg protein). Immunohistochemically, S-100a₀ antigen was localized in such epithelial cells as proximal tubules, Bowman's capsules and collecting tubules of normal kidney, and in the cytoplasm, nucleus and occasionally plasma membrane of the tumor cells. The contents of S-100a₀ protein in various lung carcinoma tissues were low (<10ng/mg protein). Serum S-100a₀ concentrations were less than 0.3ng/ml in healthy subjects, but they were significantly increased in patients with renal cell carcinoma at diagnosis, showing >0.5ng/ml in 17/32 cases (53%). Serum S-100a₀ levels were also enhanced in some patients with lung cancer (10/33, 30%), breast cancer (4/20, 20%) and other non-neoplastic diseases, indicating that S-100a₀ protein in the serum is not a specific biomarker for renal cell carcinoma. However, serum S-100a₀ concentrations in patients with renal cell carcinoma changed in parallel with the clinical course during treatment. These results suggest that serum S-100a₀ may be a useful biomarker at least for monitoring the clinical course of renal cell carcinoma.

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The present study deals with the effect of in vivo administration of interleukin 1 (IL 1) on the induction of tumor-specific immunity. Culture fluid supernatant (CFS) containing IL 1 was obtained by stimulating J774.1 cells with lipopolysaccharide. C3H/HeN mice were inoculated intradermally with viable syngeneic X5563 tumor cells, followed by five consecutive subcutaneous or intraperitoneal inoculations of IL 1-containing CFS. Lymph node and spleen cells from IL 1-CFS-treated or -untreated C3H/HeN mice 8 days after the tumor inoculation were tested for 1) cytotoxic T lymphocyte (CTL) responses as measured by subsequent in vitro sensitization with X5563 cells, 2) delayed-type hypersensitivity (DTH) responses as measured by utilizing a local adoptive transfer, and 3) tumor-neutralizing activity in a Winn assay. Lymph node cells or spleen cells from IL 1-CFS-treated X5563 tumor-bearing mice not only exhibited enhanced CTL and DTH responses, but also produced complete tumor neutralization, in contrast with cells from IL 1-CFS-untreated X5563 tumorbearing mice. In vivo protective immunity augmented by IL 1-CFS was tumor-specific and Lyt-1⁺2^- T cell-mediated. The molecules responsible for enhanced induction of tumor-specific immunity co-migrated with IL 1 activity on gel filtration. These results indicate that IL 1 has the potential to augment tumor-specific Lyt-1⁺2^- T cell-mediated in vivo protective immunity in tumor-bearing hosts.

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The involvement of cytotoxic cell-generating factor (CGF) in the generation of cytotoxic cells against syngeneic tumor (T-9) cells and in the rejection of the tumor cells has been investigated. It was found that Con A-sup (culture supernatant of concanavalin A-stimulated rat spleen cells) contained CGF, which was distinct from interleukin (IL) 2 and interferon. It should be noted that spleen cells produced CGF upon inoculation of syngeneic tumor cells into tumor-sensitized rats. Production of CGF preceded the appearance of cytotoxic cells against inoculated tumor cells. In these rats, the inoculated tumor was rejected. In contrast, spleen cells failed to produce CGF upon inoculation of tumor cells into normal rats; in these rats, cytotoxic cells were not detected and the inoculated tumor grew. These data suggested that CGF was produced as an in vivo response of the host immune system and was involved in the generation of cytotoxic T cells. CGF obtained from sensitized spleen cells was chromatographically separated from IL 1, IL 2, and colony-stimulating factor, and the chromatographically separated CGF did not contain IL 3 activity.

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To elucidate how low-mobility T cells emerge in the peripheral blood of cancer patients, lymphocytes from normal individuals were treated with cancer patients' plasma, immunosuppressive (IS) substance with or without interleukin-2, or neuraminidase. A delay in cell mobility was induced by IS substance and neuraminidase treatments, which degrade the cell surface charge. Compared to the normal mobility pattern of lymphocytes, patterns induced by these treatments were characterized by a general shift of the fast cell peak to the left side. These patterns were different from those of cancer patients in terms of the inverse relationship between slow and fast peaks. These results indicate that, though humoral factors in the peripheral blood of cancer patients take a partial role, other mechanisms might operate to induce the characteristic mobility pattern of lymphocytes. One of the possibilities, the emerging of a special T cell subset recruited from the thymus, is discussed.

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Combinations of retinol palmitate (RP) and six different anticancer agents were examined to determine their effects on the life-span of mice bearing ascites sarcoma 180 or P388 leukemia. With ascites sarcoma 180, administration of a fixed dose of RP (3.3mg/kg) considerably enhanced the antitumor effects of 5-fluorouracil (5-FU) (5mg/kg, or 20mg/kg), methotrexate (MTX) (0.5mg/kg, or 1mg/kg) and 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea (ACNU) (12.5mg/kg), when given by intraperitoneal injection. However RP failed to potentiate the antitumor effects of adriamycin (ADM) and 6-mercaptopurine (6-MP) against sarcoma 180. With P388 leukemia, RP (167mg/kg, or 333mg/kg) enhanced the antitumor effects of 6-MP (25mg/kg, or 50mg/kg), MTX (1mg/kg, or 2mg/kg), ADM (0.2mg/kg), ACNU (5mg/kg) and cis-dichlorodiammine-platinum (CDDP) (1mg/kg) to a considerable extent, but it did not potentiate the antitumor effect of 5-FU. The combination of RP with ACNU or CDDP was particularly effective against P388 leukemia.

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Cisplatin or cis-diamminedichloroplatinum(II) is a platinum coordination compound showing clinically useful antitumor activity, but the major dose-limiting factor is a dose-dependent cumulative nephrotoxicity. At the electron microscopic level, platinum has been localized in the nucleus, microsomes and cytoplasm of cells of the kidney and liver in rats. This report confirms the subcellular localization of platinum and adds one more site of platinum accumulation, the microbody, based on results obtained with an energy-dispersive X-ray microanalyzer (EDX). After daily administration of cisplatin (0.5mg/ml/kg body weight) successively for 5 weeks, accumulated platinum was detected in microbodies of hepatocytes and epithelial cells of proximal convoluted tubules of the rat. The major site of metal deposition in the kidney was the matrix of many microbodies in the epithelial cells of proximal convoluted tubules. EDX revealed the presence of platinum in those metallic deposits. The matrix of the nucleus also had metallic deposits but they were rather diffuse and platinum could not readily be detected on individual grains in the nucleus. In the liver, major damage was concentrated in hepatocytes, and other types of cells such as Kupffer cells, Ito cells and endothelial cells of capillaries were less affected. Metallic fine grains were localized in the cisterns of smooth-surfaced endoplasmic reticulum and in the matrix of microbodies. The nucleus of hepatocytes had few, if any, metallic precipitates. A specific type of metallic deposition was round aggregations of dense tubules in which platinum was detected by EDX. There was no evidence of platinum precipitation in mitochondria or Golgi complex. These findings suggest that the microbody may play an important role in degradation of the platinum complex both in hepatocytes and epithelial cells of proximal convoluted tubules.

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A phase II study of vindesine (VDS) was carried out in 21 patients with non-small cell lung cancer (NSCLC). There were 13 and 8 patients with and without prior chemotherapy, respectively. VDS was administered at a weekly iv dose of 3mg/m². Partial response was observed in two of 15 adenocarcinomas and one of 2 adenosquamous cell carcinomas, and the overall response rate was 14.3% (3/21). Myelosuppression, especially leukopenia, was the most common dose-limiting side effect. Neurotoxicity was also a common side effect but the degree was mild. It was concluded that VDS at a dose of 3mg/m² every week seems to be active against NSCLC.

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