In view of carcinoembryonic properties, γ-glutamyl transpeptidase (γ-GTP) was examined to see whether or not hepatoma-specific γ-GTP isoenzyme was found in the sera of patients with hepatocellular carcinoma. Serum γ-GTP was fractionated by using polyacrylamide gradient gel electrophoresis in sera from 224 patients with various hepatobiliary diseases, including 63 with hepatoma. γ-GTP isoenzymes in sera were separated by this method into 12 bands. Band II, which was seen in the region near the ceruloplasmin, was detected in 22 of 63 patients with hepatoma (35%), but not in patients with other diseases. In addition to the II band, an extra band (II'), which was present between II and III, was found in 13 of these 22 hepatoma patients. None of other bands was characteristic to any group of patients studied. This novel γ-GTP isoenzyme seems to be useful for examination of γ-GTP isoenzyme patterns by this technique, as one of diagnostic indices for hepatoma.

View full abstract

Mammary tumor virus (MTV) antigen expression was determined by three different techniques in milk and secondary male genital organs of mice from segregating populations between the GR and BALB/c strains by immunodiffusion test, immunofluorescence absorption test, and radioimmunoassay. One gene controls the expression of high levels of MTV antigen as seen by the immunodiffusion test of milk and the immunofluorescence absorption test in epididymis, prostate, and coagulating glands. By the more sensitive radioimmunoassay, MTV-antigens can also be found in the absence of this gene, called Mtv-2, which may be due to extrachromosomal transmission and a "second" gene, unlinked to Mtv-2.

View full abstract

Bifidobacterium infantis is a gram-positive anaerobic bacterium isolated from the feces of human infants. Studies were made on its antitumor effect on cells of an ascites Meth-A tumor induced in a BALB/c mouse with 3-methylcholanthrene. The effect of intraregional injection of this bacteria on subcutaneously transplanted tumor (25 × 10³) produced a complete regression in all the mice, when treatment with B. infantis was started from one day after tumor inoculation for 6 times, where control mice were all dead. The majority of surviving mice rejected the rechallenge of the tumor by this treatment. When tumor cells mixed with B. infantis were inoculated subcutaneously into mice, tumor did not grow in a majority of the recipient mice, but these surviving mice accepted rechallenge of the tumor. Intraperitoneal injection of B. infantis against intraperitoneally transplanted tumor also exhibited a remarkable antitumor effect. The effect decreased as the dosage of B. infantis decreased.

View full abstract

The cell-wall skeleton of Nocardia rubra, which was treated with a small quantity of mineral oil (Drakeol 6VR) and suspended in saline containing 0.2% Tween 80, was found to have potent adjuvant and antitumor activities. Present study indicated that (1) Drakeol 6VR can be replaced by metabolizable oils such as squalene and squalane, and that (2) the cell-wall skeleton preparations treated with these oils and suspended in 5.6% mannitol solution containing 0.2% Tween 80 can be stored in a lyophilized form and can be easily resuspended by the addition of sterilized water before use. The resuspended preparation of N. rubra cell-wall skeleton treated with squalene or squalane and suspended in 5.6% mannitol-0.2% Tween 80 and then lyophilized was shown to have almost the same antitumor and adjuvant activities as the cell-wall skeleton of N. rubra treated with Drakeol 6VR and suspended in mannitol-Tween 80 or freshly-prepared N. rubra preparation (Drakeol 6VR-saline-0.2% Tween 80 preparation) in transplantable tumors in syngeneic mice and on the induction of allogeneic cell-mediated cytotoxicity in mice. The advantages of these lyophilized preparations as immunotherapeutic agents for human cancer are discussed.

View full abstract

Female 2-day-old Sprague-Dawley rats were given a subcutaneous administration of either 1.25mg of testosterone propionate, 1.0mg of 5α-dihydrotestosterone, 0.1mg of 17β-estradiol, or 1.0mg of progesterone. At 50 days of age, all the rats were given 20mg of 7, 12-dimethylbenz[a]anthracene (DMBA) by a stomach tube. All the rats were killed at 300 days of age. In the rats given testosterone propionate or 17β-estradiol, lactation in the mammary gland and absence of corpora lutea in the ovaries were found. Induction of mammary carcinoma by DMBA was strongly suppressed, whereas the induction of mammary dysplasia was significantly accelerated in the rats given either testosterone propionate or 17β-estradiol. Both 5α-dihydrotestosterone and progesterone showed no remarkable changes in the induction of mammary carcinoma or dysplasia.

View full abstract

The effect of partial pancreatectomy or feeding of a protein-deficient diet containing 0.5% ethionine (ethionine diet) on pancreatic tumorigenesis of azaserine was studied in Wistar rats. Adenomas of the non-endocrine pancreas were induced in 100% of the rats of all azaserine-treated groups at 62 weeks. The size and number of adenomas induced by azaserine were significantly increased in rats treated with partial pancreatectomy or ethionine diet compared to those in non-treated rats. There was no significant difference in the number of adenomas between rats treated with partial pancreatectomy and those given ethionine diet, but the size of the tumors was significantly larger in rats treated with partial pancreatectomy than in rats receiving ethionine diet. These results indicate that pancreatic tumorigenesis by azaserine was enhanced by the regeneration induced by partial pancreatectomy or by ingestion of ethionine diet, and that the enhancing effect by partial pancreatectomy was greater than that by ingestion of ethionine diet in rats.

View full abstract

The antitumor activity of L-cell interferon was examined in experimental tumor systems. Antileukemic effect of interferon was correlated with the dose used. Interferon at 5×10⁵U/kg suppressed the growth of 3-methylcholanthreneinduced fibrosarcoma (MCA tumor) in C57BL/6 mice, but showed no significant antitumor effect in murine leukemia. However, interferon at a daily dose of 1×10⁷U/kg showed 100% increase in lifespan (ILS) in mice bearing P388 leukemia and 39% of ILS in mice bearing L1210 leukemia. Infiltration of many macrophages was observed on smears obtained from the ascites of leukemia-bearing mice treated with interferon. The interferon preparation inhibited the growth of cultured L1210 leukemia or MCA tumor cells.

View full abstract

The binding of radioactivity from 1, 1'-ethylene-bis(1-nitrosourea) (EBNU), labeled with ¹⁴C in either the carbonyl or ethylene residue, to nucleic acids, proteins, and synthetic biopolymers was studied in vitro. The radioactivity of both labeled compounds was bound to the trichloroacetic acid-insoluble fraction of L1210 cells; carbonyl-¹⁴C was bound to cytoplasmic and nuclear proteins but not to nucleic acids, but ethylene-¹⁴C was bound to both proteins and nucleic acids. Similar results were obtained in model experiments using purified nucleic acids, proteins, and synthetic polynucleotides and polypeptides. Among them, poly-lysine was the most active in the binding of radioactivity from both carbonyl- and ethylene-labeled EBNU.

View full abstract

Three kinds of serum proteins were found to increase in mice by the administration of various antitumor agents. Purification of one of these proteins was achieved by ion-exchange chromatography on a column of DEAE-Sephadex A-50 and preparative polyacrylamide gel electrophoresis. This purified protein, designated LB, is a glycoprotein with an approximate molecular weight of 80, 000, and contains sialic acid, glucosamine, fucose, mannose, and galactose. Intravenous injection of LB inhibited the growth of sarcoma-180 implanted in mice subcutaneously, but it did not exert a direct inhibitory effect on the growth of cultured sarcoma-180 cells in vitro. Furthermore, LB enhanced the antibody production of mouse spleen cells immunized against sheep red blood cells, as measured by the increase of the number of plaque-forming cells. This immunological effect of LB was found to be dose- and time-dependent, and independent of the genetic control by the major histocompatibility-2 complex of mice.

View full abstract

Methyl 1-(5-fluoro-1H-2-oxopyrimidin-4-yl)-β-D-glucopyranuronate (FU-O-G), O-glucuronide of 5-fluorouracil, showed a moderate antitumor activity and significantly little toxicity when given iv to mice bearing L1210 leukemia. However, FU-O-G, when combined with glucose given ip, exhibited the greatest therapeutic activity in comparative study with 5-fluorouracil (5-FU) and 1-(2-tetrahydrofuryl)-5-fluorouracil (FT-207) in the same experimental system. Therapeutic ratio and maximum survival effect of the compound with glucose were 2.5 and 78% increase in lifespan (ILS), whereas those of 5-fluorouracil and 1-(2-tetrahydrofuryl)-5-fluorouracil were 1.1 with 42% ILS and 1.2 with 45% ILS, respectively. Enhancement of antitumor activity of the compound was maximal when glucose was given simultaneously with FU-O-G, and increased along with increasing dose level of glucose.

View full abstract

A pathological and epidemiological study on 849 patients with malignant lymphoma in Kagoshima Prefecture, the southernmost prefecture in Japan, during the 12 years from 1965 to 1976 yielded an age-adjusted annual incidence rate of 3.02 (males 4.04 and females 2.15) per 100, 000 population. The incidence has been increasing recently, and especially apparent in the higher age groups of the 60s to 70s. Some local areas showed an accumulated incidence of malignant lymphoma. In this present series, the prevalence of diffuse lymphoma in nodal lymphoma and cutaneous lymphoma in extranodal lymphomas was conspicuous. These results were discussed in connection with a high incidence of T-cell lymphoma in this prefecture.

View full abstract

Effect of dietary phenobarbital on the development of enzyme-altered islands (EAI) and hepatocellular carcinomas initiated by a short-term treatment with 3'-methyl-4-(dimethylamino)azobenzene (3'-Me-DAB) or diethylnitrosamine (DENA) in the rat was studied. Phenobarbital generally enhanced the proliferation of carcinogen-induced (enzyme-altered) cells so that the number and size of EAI were much larger in phenobarbital-fed groups in early stages than in control groups kept on a basal diet. The growth rate of EAI was, however, not uniform and only a small minority progressed to large islands or carcinomas. In groups initially treated with 3'-Me-DAB for 3 weeks, the enhancing effect of phenobarbital on cancer production was remarkable by the 36th week whereas in groups treated with 3'-Me-DAB for 1 week, no cancer developed by the 60th week, although a large number of small EAI appeared. Thus a summation effect of the carcinogen was observed even when the carcinogen was given for a short period as an initiator. The enhancing effect of phenobarbital was also marked in the groups initiated by DENA, in which, however, considerable number of carcinomas developed in control groups also. The carcinogen-induced cells or EAI appeared inherently different, as the population, in the potentiality to progress to carcinoma according to the difference of an initiator.

View full abstract

Proliferation of hemopoietic stem cells was maintained by the addition of bone marrow cells on the adherent cell colonies which had formed on the glass surface of culture bottles by 3 weeks of primary bone marrow cell culture, the formation of such adherent colonies being rather incidental. Addition of bone marrow fragments was attempted in order to enhance the formation of adherent cell colonies, based on the hypothesis that the formation of adherent cell colonies requires close cell-to-cell interaction. By starting the bone marrow cell culture with fine fragments, formation of adherent cell colonies was achieved. The culture system also retained the proliferation of hemopoietic stem cells for several weeks.

View full abstract

Antibacterial effect of 1, 3-bis(2-chloroethyl)-1-nitrosourea (BCNU) on isogenic strains of Escherichia coli with normal or defective DNA repair system was studied. Growth of the strains lacking rec-A gene was inhibited by BCNU with much lower concentration than in the case of those possessing it. This result suggests that BCNU causes DNA damages in E. coli, which are effectively repaired by postreplication repair.

View full abstract

The so-called immunostimulants used in potentiating the decreased immune response in patients with malignancy were investigated for their ability to activate human complement system in vitro. BCG, a protein polysaccharide from mycelia of Coriolus versicolor (PS-K), and a streptococcal preparation (OK-432) were found to activate both the classical and alternative pathway of the complement.
It is speculated that the ability of these preparations to activate the complement system might indicate that they have another function in the restoration of the decreased immune response in patients with malignancy, in addition to their well-established function to stimulate cellular immunity.

View full abstract

Antitumor activity of newly synthesized 2, 6-bis (halomethyl)piperidines was studied in vitro and in vivo, using ascites hepatoma cell lines AH-13 and AH-44, sensitive and insensitive to alkylating agents, respectively. AH-13 was extremely sensitive both to in vitro lethal action and to in vivo antitumor effect of 2, 6-bis(bromomethyl)piperidine hydrobromide (CAP-9) and 2, 6-bis(iodomethyl)piperidine hydrochloride (CAP-12), but was resistant to 2, 6-bis(chloromethyl)piperidine hydrochloride (CAP-8). On the other hand, AH-44 was resistant to all these compounds, and cytotoxic activity of the compounds decreased in the order of CAP-12, CAP-9, CAP-8, and CAP-2, when AH-44 cells were incubated with the compound for different periods. CAP-12 was found to be the only effective in prolonging the lifespan of rats bearing AH-44, given intraperitoneally 3 times a day at a dose of 28mg/kg for 7 days.

View full abstract

Tissue distribution of 3-[(4-amino-2-methyl-5-pyrimidinyl) methyl]-1-(2-chloroethyl)-1-nitrosourea hydrochloride (ACNU), a new water-soluble antitumor agent, in tumor-bearing mice and rats was studied by the whole-body autoradiography after intravenous administration of two compounds labeled with ¹⁴C in different positions of the molecule.
After intravenous administration, radioactivity was widely distributed and disappeared rapidly from the body. Specific retention of ethylene-¹⁴C of ACNU was observed in tumor tissues, liver, and thymus of mice and rats even after disappearance of radioactivity from the other tissues.

View full abstract

Mitomycin-C, at a dose of 0.50 or 0.25mg/kg/day, injected when the tumors were 1 week old, resulted in a complete destruction of rat colon adenocarcinoma. Repeated intraperitoneal injections of 0.50mg/kg/day of mitomycin-Chad a strong inhibitory effect on the growth of 2- or 3-week-old rat colon adenocarcinoma.

View full abstract

Susceptibility to 1, 2-dimethylhydrazine (DMH) carcinogenesis was comparatively studied between two rat strains, Wistar-Furth (WF) substrain rats from a colon cancer family and Long-Evans (LE) strain rats. Ten-week-old rats were injected with DMH (20mg/kg body weight) weekly for 20 weeks, and sacrificed at the 10th, 15th, 20th, and 25th week after the last injection. LE rats developed benign and malignant colon tumors more frequently in terms of crude incidence and the number of tumors per rat. The predilection site of colon tumors induced by DMH was the descending colon in LE rats, where only a few cases of tumors were found in WF rats. Autoradiographic study did not show any apparent difference between the two strain rats of either DMH-treated or non-treated control in the number of 3H-thymidine labeled cells or of mitotic cells in the mucosa of the descending colon. It is likely that a resistantstrain rat (WF) for DMH carcinogenesis has emerged.

View full abstract

An attempt was made to study the effect of testosterone on the development of X-ray-induced prostate cancer in rats. Five-week-old male Sprague-Dawley rats were castrated and replaced with 2.5 or 5.0mg of testosterone thereafter once a month for the life span. At 6 weeks of age, they were locally (pelvic region) irradiated with a total of 5, 000 rad (5×1, 000 rad) of X-ray at an interval of 2 or 3 days. Prostate cancer developed only in the castrated and testosteronetreated rats with an incidence of 4/12 (33.3%) during the period of 7 to 11 months after irradiation, none in the castrated (0/13) and non-castrated rats (0/11). This indicated a promoting role of testosterone in the genesis of prostate cancer.

View full abstract

Effect of caffeine on induction of 6-thioguanine-resistant (6TG^r) colonies in V79 Chinese hamster cells by ultraviolet (UV) irradiation was examined by the replating method. Post-UV treatment with 1mM caffeine had neither synergistic nor suppressing effect on the induced 6TG^r frequency, in contrast to a marked killing potentiation as a result of inhibition of replicative repair. This suggests a possible involvement of other repair mechanism (s) rather than replicative repair in UV mutagenesis.

View full abstract

The surface receptors for Fc regionof IgG (Fc recepter) appeared at stage of metamyelocytes in patients of chronic myelogenous leukemia (CML). Fc receptor was found in 88.6∼100% of segmented cells form CML patients and 100% of segmented cells from control adults.

View full abstract

High proportion of the lymphocytes in the malignant pleural effusion are Tcells indicating their accumulation from peripheral blood in the pleural cavity. T cells seem to play an important role in the local defense activity against tumor invasion in the pleural cavity.

View full abstract

Ahuman glioma cell line was transplanted subcutaneously to a mouse strain with hereditary asplenia and athymia. The tumor that developed in the mouse showed histological characteristics compatible with those of the original tumor.

View full abstract

A human glial cell line synthesizing nervous tissue-specific (S100) protein was established. S100 protein in this cell line was detected by indirect immunofluorescence method and Ouchterlony method.

View full abstract