Irradiation effects on wound contraction using a connective tissue model

To analyze irradiation effects on wound contraction, fibroblasts harvested from human oral mucosa were irradiated (single 2-, 4-, 6-, 8-, and 10-Gy exposures of x-rays). The irradiated fibroblasts were examined for growth ability, and they were cultured three-dimensionally in hydrated collagen gels. The irradiation inhibited growth of fibroblasts and contraction of collagen gels in a dose-dependent manner. In addition, inhibition depended on the duration after exposure. The organization of actin filaments of fibroblasts in this model was examined with fluorescent dye-conjugated phalloidin. Many elongated cell projections were formed in cells of the control group, but the cell projections were almost disrupted in the irradiated cells. X-ray irradiation is thus shown to inhibit wound contraction by affecting the organization of actin filaments in fibroblasts.

Checkup interval and cancers in automated multiphasic health testing and services

The purpose of this study was to disclose which types of cancer and how many persons with cancer were detected among the AMHTS examinees of our AMHTS center by using the hospital information retrieval system, and to study the relationship between cancer and the number of examinees, checkup intervals, and frequency in AMHTS. The examinees who had checkups more than twice were divided into three groups based on their checkup intervals: within one year, one to two years, and over two years. The relationship between cancer ratios and checkup intervals was evaluated in each group of examinees. In those having checkups within one year and from one to two years the cancer rate was 2.9 patients per 1,000 persons. However, in those having checkups after a two-year period or longer, the cancer rate was 4.3, clearly greater than the rate of the other two groups.

[UV-microspectrophotometric and flow cytometric analysis of the same samples using DAPI/HP staining]

A simple one-step double staining with DAPI and hematoporphyrin (HP) was used for UV-microspectrophotometric (UV-MSPM) and flow cytometry (FCM) analysis of the same samples. The specimens analyzed included fresh biopsy and/or surgical materials, trimmed 50 microns-thick paraffin sections and smears (with the latter not available for FCM). We provided the special technology for preserving the cytoplasm as far as possible to permit measurement of cell size and N/C ratio. DAPI indicates DNA content under 365 nm and HP of total protein content under 670 nm UV-MSPM. The DAPI can measure the nuclear size and the latter the cell size. DAPI/HP staining yielded much more accurate measurements than staining with FITC and PI. The use of both MSPM and FCM with cell sorting on the same samples is very helpful in cytology and histopathology for evaluating and differentiating borderline lesions and grade of malignancy, as well as oncostatic effectivity. Our goal is to combine this technology with the automated cytologic screening system CYBEST, which was developed by Tanaka et al, based on a morphometric device.

Expression of proto-oncogenes and tumor suppressor genes in in vitro cell lines derived from a thymus, thymoma, and malignant thymoma of rats

To analyze the processes of the development of thymoma and malignant thymoma from normal thymic epithelial cells, we have examined the expression of 15 proto-oncogenes and tumor suppressor genes in seven in vitro epithelial cell lines established from a normal thymus (TuD1-1, TuD1-3, and TuD1-5), thymoma (TaD1-3 and TaD1-8), and malignant thymoma (MTHC-1 and MTHC-3) of rats. Northern blot analysis indicated that most of these genes examined were transcribed at similar levels. However, higher levels of transcription of epidermal growth factor receptor (EGFR) were observed in TuD1-1, TuD1-3, TuD1-5, TaD1-3, and TaD1-8 cells than in MTHC-1 and MTHC-3 cells. Conversely, four of the former five cell lines showed no TGF-beta transcription while the latter two cell lines had high levels of its expression. In addition, c-fos proto-oncogene was highly expressed in TuD1-5 cells, which showed the fastest growth rate among the seven cell lines. These results denote that some molecular changes in the regulation of gene expression occurred in the processes of malignant transformation of thymic epithelial cells.

An intrinsic thymic epithelial abnormality is responsible for the spontaneous development of predominantly lymphocytic thymomas in BUF/Mna rats

The nature of tumorigenesis of predominantly lymphocytic thymoma was examined using an animal model. Rats of the inbred BUF/Mna strain were found spontaneously to develop predominantly lymphocytic thymomas, histologically indistinguishable from their human counterparts, at an incidence of virtually 100%. Thymic rudiments of BUF/Mna rats grafted 17 months previously under the renal capsule of young athymic ACI/NMs-rnu/rnu rats also gave rise to similar lesions. The lymphocytes in the thymomas expressed T-cell antigens (rat Lyt-1 and Lyt-2.3), as in the normal case, and ACI rat specific antigen. When BUF/Mna rats of thymoma age were irradiated with a lethal dose of 12 Gy and then received a single injection of bone marrow cells (8 x 10(7)) from BALB/c-nu/nu mice, thymomas were re-formed three weeks later (in 2 of 5 rats) with the replacement lymphocytes expressing mouse Thy-1.2 antigen. These results indicate that an intrinsic thymic epithelial abnormality is responsible for the development of predominantly lymphocytic thymomas in BUF/Mna rats.

RFP is a DNA binding protein associated with the nuclear matrix

We reported that the RFP gene encodes a protein with putative zinc finger domains and was involved in the activation of the ret proto-oncogene. To further characterize the RFP protein, we developed a polyclonal antibody against the product synthesized from a fragment of the RFP cDNA expressed in Escherichia coli. Western blot analysis showed that RFP was identified as a 58 kDa protein in cell lysates from four human and rodent cell lines and from mouse testis. In addition, a unique 68 kDa protein was detected in the testis. Using AH7974 (rat ascites hepatoma) and Raji (human Burkitt lymphoma) cells, we demonstrated strong association of RFP with the nuclear matrix. Furthermore, RFP solubilized from the nuclear matrix had DNA-binding activity although it appears to bind more preferentially to double-stranded DNA than to single-stranded DNA. These results thus suggest that RFP may play a role in molecular processes which occur in the nuclear matrix.

Establishment and characterization of a malignant melanocytic tumor cell line expressing the ret oncogene

We established a cell line (designated Mel-ret) from a melanocytic tumor developed in a metallothionein/ret transgenic mouse. Unlike primary melanocytic tumors, which did not show malignant features, when the Mel-ret cells were transplanted into nude mice they invaded into surrounding tissues and had metastatic ability. Although the Ret proteins were expressed at similar levels in the cell line and the primary tumors, the level of tyrosine phosphorylation in the Mel-ret cells was much higher than that in the primary tumors. In particular, an 85-kDa tyrosine-phosphorylated band was specifically detected in the Mel-ret cells. These results suggest that the increase in tyrosine phosphorylation may be responsible for malignant transformation of the Mel-ret cells. Immunofluorescence and cell fractionation studies showed that the Ret proteins and most of tyrosine-phosphorylated proteins in the Mel-ret cells localized in the membrane fraction. No activation of phosphatidyl-inositol-3 kinase (PI-3 kinase), a target protein for several tyrosine kinases, was detected in the Mel-ret cells.

Low frequency of rearrangements of the ret and trk proto-oncogenes in Japanese thyroid papillary carcinomas

We investigated the frequency of rearrangements of the ret and trk proto-oncogenes in Japanese thyroid tumors. DNAs from 38 thyroid papillary carcinomas and 14 follicular adenomas were analyzed by Southern blotting. Rearrangements of the ret and trk proto-oncogenes were detected in one and two papillary carcinomas, respectively, but not in follicular adenomas. Analysis by a reverse transcriptase-polymerase chain reaction method showed that the ret rearrangement-positive tumor contained the PTC/retTPC chimeric transcript, which was reported to be found specifically in thyroid tumors and adenomatous goiter. We also found that rearranged mRNA of the trk proto-oncogene was expressed at high levels in one of two trk rearrangement-positive tumors. Our results indicated that the frequency of rearrangements of these proto-oncogenes in Japanese papillary carcinomas was much lower than that in Italian patients.

Distribution of the collagen binding heat-shock protein in chicken tissues

We examined the tissue distribution of heat-shock protein MW 47,000 D, hsp47, which binds to native and denatured collagen including Types I, III, and IV, in various chicken tissues by Western blotting and immunohistochemical methods. hsp47 was located on fibrocytes or fibroblasts in the connective tissue in various organs, chondrocytes in the cartilage, smooth muscle cells in the gastrointestinal tract and blood vessels, vitamin A storage cells in sinusoidal area of liver, endothelial cells in blood vessels, and epithelial cells of renal glomeruli, tubules, and basal layer of epidermis. These cells also co-expressed a certain type of collagen molecule. Furthermore, in developing embryos, fibroblasts and chondrocytes expressed hsp47 before the deposition of collagen Type I or Type II in the surrounding tissue. These results indicate that the binding of hsp47 to collagen molecules has important biological significance.

Aging-associated deletions of human diaphragmatic mitochondrial DNA

It is known that respiratory function deteriorates with age. Endogenous damage to DNA is thought to contribute to the aging process. The mitochondrial oxidative phosphorylation system, a bio-engine, consists of five complexes, and 13 subunits of those complexes are biosynthesized from information encoded in mitochondrial DNA. Mitochondrial DNA is shown to have a much higher mutation rate than nuclear DNA. We examined the diaphragms obtained at autopsy from 34 humans, 23 men and 11 women, ranging in age from 25 to 85 yr, for mitochondrial DNA deletions using the polymerase chain reaction method. Multiple mitochondrial DNA deletions were detected particularly among the elderly; the number of deletions in those over age 70 was significantly higher than in those under age 40. The occurrence of a 3.4-kbp deletion of mitochondrial DNA increased with age, i.e., 0% of those under age 30, 20.0% of those in their forties, 25.0% of those in their fifties, 28.6% of those in their sixties, 72.7% of those in their seventies, and in all of those over age 80. The mutation was based on the directly repeated sequence, 5'-TCACCCC-3', which exists in both the CO3 gene and the ND5 gene. Replication impairment occurred at that directly repeated sequence, which caused the elimination of a genome between the CO3 gene and the ND5 gene, and information for biosynthesis of four subunits in complex I (ND3, ND4L, ND4, and ND5), one in complex IV (CO3), and five transfer RNA genes was missing.(ABSTRACT TRUNCATED AT 250 WORDS)

Abnormal increase in multinuclear macrophages in primary cultures of BUF/Mna rat thymomas

The in vitro characteristics of spontaneous thymomas from BUF/Mna rats, a strain with a high incidence of these tumors, were studied. In primary cultures, the adherent cells consisted of mononuclear macrophages, mono- and multi-nuclear epithelial cells and some fibroblastic cells on day 3. The macrophages rapidly increased in number with the formation of large multinuclear cells by day 9. A modest increase in the number and nuclearity of macrophages was also noted in adherent cultures of normal thymuses from 5-week-old BUF/Mna rats. On the other hand, in cultures of thymic cells from 1-year-old or 5-week-old ACI/NMs rats, a normal control rat strain, macrophages did not increase in number and only rarely formed multinuclear cells in adherent cell cultures. These results suggest that abnormal proliferation signal(s) to thymic macrophages and/or their progenitor cells accompanies and may be involved in the development of thymomas in BUF/Mna rats.

[Preliminary screening for antiviral AIDS drugs. III. Report on fiscal year 1990]

Preliminary screening for antiviral AIDS drugs has been carried out using three different in vitro assay systems. Among 106 samples tested, five were found to inhibit the growth of HIV in vitro. Two of five have a hopeful sign, as the range of effective doses of the samples is wide.

Endocrine cells in a normal breast and non-cancerous breast lesion

The authors confirmed the presence of endocrine cells for the first time in a normal breast as well as in a non-cancerous lesion of the breast. One hundred and eighty-eight blocks of normal breast tissues in 44 cases and 74 blocks of non-cancerous lesions in 35 cases were examined. Argyrophil cells were found in one block from a normal breast and in one block from a phyllodes tumor. Argyrophil cells in the normal breast showed positive reaction to anti-endocrine granule constituent (EGC) antibody with immunohistochemical method. Argyrophil cells found in the phyllodes tumor gave positive reaction to both anti-EGC and anti-serotonin antibodies. The present study is thought to be the first report in the literature of serotonin-positive cells in a non-cancerous breast lesion, a phyllodes tumor.

Tissue distribution of mouse mammary tumor virus (MMTV) antigens and new endogenous MMTV loci in Japanese laboratory mouse strains

The distribution of mouse mammary tumor virus (MMTV) antigens was studied by the immunoperoxidase method in the II-TES and I-TES mouse strains as well as their progenitors, CS and DBA/2 strains. In the II-TES, I-TES and CS strains, and BALB/c mice foster-nursed with these strains, MMTV antigens were found not only in epithelial cells of the mammary glands but also in those of other tissues including the seminal vesicle, vas deferens, epididymis, prostate, parotid, submandibular, lacrimal, sebaceous, and urethral glands. In DBA/2 and BALB/cfDBA/2 mice, however, the MMTV antigens were found only in the mammary glands. Electron microscopic examination showed MMTV particles in these organs. When we examined the presence of Mtv-1 and 2 proviruses, which are known to be responsible for MMTV expression, in the genomes of the II-TES, I-TES, CS and DBA/2 strains by Southern blotting, Mtv-2 was not found in any of the mice and Mtv-1 was found in the II-TES and DBA/2 mice but not in the I-TES and CS mice. Instead, four new endogenous MMTV loci, which have never previously been reported in laboratory mouse strains, were detected in the genomes of the II-TES, I-TES and CS strains. One (designated Mtv-42) was common in the three strains and the other three (designated Mtv-43, 44 and 45) were common in the II-TEX and I-TES strains or the II-TES and CS strains. These results thus suggest that new endogenous MMTV loci may be responsible for MMTV expression in a variety of tissues of these three strains.

Inhibition of wound contraction by papaverine: in vitro analysis with a submucosal tissue model

We studied the effect of topical application of papaverine, a smooth-muscle relaxant, on the contraction of open, dorsal skin wounds in rats. Wound contraction was inhibited significantly in papaverine-applied wounds compared with saline-dressed control wounds. The in vitro effect of papaverine on wound contraction was studied by using human oral fibroblasts cultured three-dimensionally in the hydrated collagen gels containing papaverine. Papaverine inhibited collagen gel contraction in a dose-dependent manner. Any change in actin filament organization in fibroblasts cultured three-dimensionally in the collagen gels was observed by staining the filaments with fluorescent dye-conjugated phalloidin. In the control cultures, well-organized stress fibers were formed in the cell projections; in papaverine-treated fibroblasts, during the early stages of the treatment, the stress fibers were disrupted and actin filament aggregation was observed. In addition, papaverine induced a delay in the formation of the processes in fibroblasts cultured in collagen gels. These results indicate that wound contraction inhibition by papaverine is mediated by its effects on the organization of actin filaments of fibroblasts.

The ret oncogene products are membrane-bound glycoproteins phosphorylated on tyrosine residues in vivo

We identified ret oncogene products in NIH 3T3 cells transformed by the ret oncogene (NIH(ret)) and a cell line (Lym-ret) established from pre-B cell lymphoma which developed in E mu-ret transgenic mice. Using the polyclonal antibody against the kinase domain of ret, two glycoproteins with apparent molecular weights of 100 kd and 96 kd were found in both cell lines, although the expression level of the 100 kd protein was much higher than that of the 96 kd protein. Cell fractionation experiments indicated that the 100 kd protein was present predominantly in the membrane fraction while the 96 kd protein was found in both membrane and cytosol fractions. Western blot analysis indicated that the 100 kd ret protein was phosphorylated on tyrosine residues in vivo.

Ultrastructural cytochemistry of eosinophilic inclusions in the cells of hyperplastic nodules and hepatomas in mouse liver

Intracisternal inclusions in the cells of 48 hyperplastic nodules and hepatomas in mouse liver were examined by electron microscopy to determine the precise compositions of the inclusions in relation to their ultrastructure, and some preliminary attempts at isolation and chemical analysis of the inclusions were performed. We classified the inclusions into two types. One was mainly of larger size, consisting of a single electron-lucent core and a granular cortical zone of high electron density. The other type was smaller, with a number of tiny, electron-lucent areas crowded into the central area instead of a single core. The cortical material of the inclusions was digested by pepsin treatment of thin sections, whereas the core and the electron-lucent areas within the cortical zone were not extracted. On the other hand, in materials treated with ethanol before post-osmication, only the core and electron-lucent areas within the cortical zone were partially extracted. The ultrastructure of the isolated inclusions was very similar to that of inclusions in situ. The chemical composition of the isolated fractions was estimated to be 60% protein and 35% lipid. Electrophoretically, the protein of this fraction showed a single band. We conclude that the cortical substance is proteinaceous in nature, probably consisting of a single protein or a group of proteins with identical electrophoretic mobility, whereas the core is composed of lipid. The possibility that the inclusions are due to an impairment in the mechanism of intracellular lipoprotein transport is discussed.

Detection of lung cancer in clinical specimens using a human monoclonal antibody HB4C5-clone 3

Biopsies of 18 patients with lung cancer and cellular specimens of 21 lung cancer patients were analyzed with human monoclonal antibody HB4C5-clone 3 using avidin-biotin-peroxidase techniques. Analyses with the biopsies showed that HB4C5-clone 3 reacted with 16 of 18 biopsy specimens at a high rate of about 90% and reacted with all specimens of five adenocarcinoma tissues, five of six squamous cell carcinomas, two of three large cell carcinomas, both specimens of small cell carcinomas, and both of the other types of carcinomas. In all the reactive cases, the monoclonal antibody was reactive with greater than 50% of cancer cells. With cellular specimens of lung cancer patients, HB4C5-clone 3 reacted with 7 of 13 adenocarcinoma specimens, two of six squamous cell carcinomas, and one of two small cell carcinomas. The immunoreaction with HB4C5-clone 3 was observed in sites of the cytoplasm of cancer cells. From these data, HB4C5-clone 3 is considered to be of potential use in diagnoses of tissues and cellular specimens of lung cancer.

Establishment and characterization of immortalized non-transplantable mouse mammary cell lines cloned from a MMTV-induced tumor cell line cultured for a long duration

During the culturing of a mouse mammary tumor cell line, MuMT73, maintained in vitro for more than a decade, we found morphological heterogeneity in its cells; some showed contact inhibition in their growth, some formed domes and some grew criss cross and piled up. In trying to clone the cell line to isolate cells showing contact inhibition or dome formation, we were able to establish six clonal cell lines. These six cell lines were categorically divided into three groups according to their phenotypical behavior, Groups A, B and C. Group A (clones 1, 5 and 7) cells had a property of contact inhibition. They induced no tumor when injected into the subcutaneous tissue of the back, nor even when injected into the mammary fat pads or under the kidney capsule of syngenic or nude mice, and therefore were thought to be non-malignant in nature. They were positively stained by anti-keratin antiserum and had mouse mammary tumor viruses (MMTVs). Group B (clone 6) cells grew in a crisscross pattern and piled up, and they induced tumors when injected into the subcutaneous tissue of the back of mice. Group C (clones 3 and 4) cells formed domes in their growth and induced some tumors in the mammary fat pads and under the kidney capsule of KSN nude mice. In Southern blots with MMTV-env probe, numerous exogenous MMTV proviruses were detected in these cell lines. The insertion patterns of these proviruses in cells of non-malignant clonal lines (Group A) resembled those of malignant lines (Group B), except one band (about 26 Kb), but were considerably different from those of intermediate lines (Group C). On the other hand, no difference was detected in Southern blots with int-1 or int-2 probes among the non-malignant, intermediate and malignant clonal cell lines.

Diurnal rhythm of serum steroid hormone levels in the Japanese whiting, Sillago japonica, a daily-spawning teleost

Ovarian developmental stages and serum steroid hormone levels were examined at six different times of day (0100, 0600, 1000, 1300, 1600, 2000 h) in a marine teleost, the Japanese whiting Sillago japonica, which has an asynchronous-type ovary containing oocytes at various stages of development and spawns every day during a period ranging up to three months. The largest oocytes in the ovaries at the active vitellogenic or post-vitellogenic stages were found between 0100 and 1300 h. Oocyte maturation indicated by germinal vesicle breakdown (GVBD) occurred at 1600 h, and ovulated oocytes were observed in the ovaries collected at 2000 h. These processes were accompanied by a significant daily change in serum steroid hormone levels. The serum level of estradiol-17β showed a peak in fish with mature oocytes sampled at 1600 h. In these fish, the second-largest oocytes in the ovaries were at the initial stage of vigorous vitellogenesis, the secondary yolk stage. Therefore the highest level of serum estradiol-17β was considered to be due to the second-largest oocytes. Testosterone levels remained low and constant throughout the experimental period. The serum levels of 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-diOHprog) peaked at 1600 h at which time all fish had mature oocytes. These results indicate that the Japanese whiting possesses a diurnal rhythm of oocyte development including vitellogenesis, oocyte maturation and ovulation, and further suggest that daily cycles in oocyte growth and maturation which simultaneously take place in an ovary are regulated by diurnal secretions of estradiol-17β and the maturation-inducing steroid, 17α,20β-diOHprog.

Establishment of functional epithelial cell lines from a rat thymoma and a rat thymus

Seven clonal epithelial cell lines from a thymoma of an (ACI/NMs x BUF/Mna)F1 rat and seven clonal epithelial cell lines from an ACI/NMs rat thymus were established in a medium containing 1 microM dexamethasone (DM) and were characterized cytologically. Long-term treatment of DM stabilized the epithelial nature of these epithelial cells irreversibly. The established cell lines showed a polygonal shape, were positively stained with antikeratin antiserum and had tonofilaments and desmosomes. Species of their keratin peptides were the same as those of normal thymic epithelial cells in primary cultures. The cell lines were positively stained with Th-4 monoclonal antibody which preferentially stains the medullary epithelial cells of the thymus, but not with Th-3 which preferentially stains the subcapsular and cortical epithelial cells of the thymus. The cells from the rat thymoma were much larger than those from the normal thymus, as reflected in their primary cultures. No transformed phenotypes, such as high growth rate, high saturation density, anchorage independency, low serum dependency and so on, were found in the cell lines from the thymoma as in the cell lines from the normal thymus by in vitro assays. DNA synthesis of the thymic lymphocytes was stimulated by culturing with a line of rat thymoma with no lectins. Thymic lymphocytes strongly bound on the cell lines from the thymoma and changed the shape of the cells. These cell lines may be useful to investigate the mechanism of thymomagenesis and the interactions between epithelial cells and thymocytes in the rat thymoma.

[Experimental study relating to the anti-cancer effect of doxifluridine]

We investigated the anti-cancer effect of Doxifluridine (5'-deoxy-5-fluorouridine: 5'-DFUR) on an experimentally prepared tumor bearing mouse.

METHOD

A 20-methylcholanthrene induced squamous cell cancer was prepared on the skin of ddN female mouse and 5'-DFUR was administered orally by catheter (90 mg/kg, 150 mg/kg, 210 mg/kg and physiological saline 0.5 ml/body). The each group consisted of 10 mice. Oral medications were performed once a day for one week (6 days continuous duration) and these medications were continued during a total period of four weeks. Once a week, the general condition of the animals was checked and at the same time, the size (length x width) of the tumor was measured, and the anti-cancer effect was determined.

RESULT

It was noted between the control and 5'-DFUR medication group that there was a marked effectiveness on the rate of decrease in size and disappear of the squamous cell cancer according to the medication of 5'-DFUR. It regarded to the amount of 5'-DFUR, that there was a significant difference in the anti-cancer effect between 90 mg/kg and 210 mg/kg groups and between 150 mg/kg or 210 mg/kg and control groups. However, the difference could not be observed between 90 mg/kg and 150 mg/kg groups and between 150 mg/kg and 210 mg/kg groups.

Genetic regulation of the development of glomerular sclerotic lesions in the BUF/Mna rat

BUF/Mna strain rats spontaneously develop renal glomerular sclerotic lesions (RSL) at a nearly 100% incidence, diagnosed by hyperalbuminuria (greater than 500 mg/dl) and glomerular lesions morphologically resembling one type of human focal glomerular sclerosis (FGS). Genetic segregation of RSL development was studied by crossing the BUF/Mna strain with two other rat strains, WKY/NCrj and ACI/NMs, which were free of RSL. Two autosomal recessive genes in the BUF/Mna rats were found to determine the susceptibility to RSL in both combinations of crosses.

Adenomatous hyperplasia and adenomas in the lung induced by chronic feeding of butylated hydroxyanisole of Japanese house musk shrew (Suncus murinus)

A carcinogenicity study on butylated hydroxyanisole (BHA) was carried out in Japanese house musk shrews (Suncus murinus) (suncus), which have no forestomach. BHA was mixed with the basal diet and was processed into pellets. One hundred and twenty-two female and 130 male suncus were maintained with a diet containing 0, 0.5, 1.0 or 2.0% BHA for 80 weeks. All of the suncus of the 2.0% BHA groups died of bleeding in the gastrointestinal tract within 8 weeks after the commencement of the treatment. The majority of the animals in the other groups survived for greater than 52 weeks. Adenomatous hyperplasias of the lung were induced in suncus of both sexes of the 0.5 and 1.0% BHA groups at significantly higher rates than in the control groups. Lung adenomas were also induced in three suncus of the BHA groups. Pilosebaceous and musk gland tumors, mammary carcinoma, kidney hemangioma and other tumors developed in a few suncus, with no significant differences between the groups. The present study indicates that BHA induces adenomatous hyperplasia of the lung in the suncus.

Thymic lymphomas induced by N-propyl-N-nitrosourea (PNU) in the BUF/Mna rat, an inbred strain with a high incidence of spontaneous thymoma

N-Propyl-N-nitrosourea (PNU) is known to be a strong leukemogen, inducing myelogenous leukemia or thymic lymphoma in some strains of rat. The thymic lymphomagenic effect of PNU has been demonstrated in F344 rats. On the other hand, the BUF/Mna rat has been established as an inbred strain that develops spontaneous thymomas after one year of age. In the present experiment, PNU was continuously administered in drinking water to male and female BUF/Mna rats starting at 5 weeks of age. Thymic lymphomas were induced in all PNU-treated rats with an average latent period as short as 14 experimental weeks. These results show the high susceptibility of the BUF/Mna rat to the lymphomagenic activity of PNU. The BUF/Mna rat is an ideal strain for studies on epithelial cell-lymphocyte interaction, not only in the development of thymic lymphomas but also in that of spontaneous thymoma. Karyotypes of twelve primary thymic lymphomas induced by PNU were analyzed for chromosomal abnormalities. Chromosomal abnormalities were often found in chromosomes 11 and 2. In some types of abnormality, dup (11q) and del(2q) were most frequently observed. In addition, trisomy of chromosome 7, on which the c-myc gene is mapped, was observed in five lymphomas, and monosomy of chromosomes 20 and X in six and five cases, respectively, though these changes were generally observed in a minor cell population in each case.

Unique male mammary tumors developing in the inbred soft-furred field rats Millardia meltada

Inbred lines of the soft-furred rat, Millardia meltada, were studied with special reference to spontaneous male mammary tumors. Adult males had the hyperplastic, pigmented inguinal mammary tissues and frequently developed bilateral mammary tumors. The tumors, no longer pigmented, were histologically well-differentiated adenocarcinomas associated with the myoepithelial cells and showed a variety of growth patterns depending on the stage of progression. They were transplantable to male, but not to female or castrated male nude mice. A significant number of androgen as well as estrogen binding sites were demonstrated in the nuclei of the transplanted tumor cells by in situ autoradiography. Neither virus particle nor mouse mammary tumor virus-specific antigen expression was detected in the tumor cells by electron microscopic and immunohistochemical studies. Normal females were generally free of pigment and tumor, although the androgen treatment induced marked pigmentation (deposit of nonfluorescent lipofuscin and hemosiderin) and hyperplasia of the female mammary epithelial cells, without a tumor. Possible relationships between pigmentation and tumor development were considered.

[A noninvasive study on characteristics of the left ventricular function in elderly hypertensive patients]

To characterize the left ventricular (LV) systolic and diastolic function in elderly hypertensives, mechano-and echocardiography was performed in 27 elderly patients more than 65 years of age (20 hypertensives and 7 normotensives) and 46 middle-aged patients (34 hypertensives and 12 normotensives). In normotensives, a positive correlation was found to exist between age and blood pressure, LV wall thickness, II-RF interval and the A/E ratio, whereas the correlation of age to systolic parameters such as ET/PEP and EF was absent. This suggests that the LV diastolic function was impaired progressively by aging with preservation of the LV systolic function. In elderly hypertensives, LV systolic function was deteriorated and the A/E ratio increased as diastolic blood pressure became elevated. The A/E ratio also increased in this group as compared with that in middle-aged hypertensives, although the differences was not statistically significant. Unlike those in middle-aged hypertensives, the indices of LV function except the elevated blood pressure and the increased cardio-thoracic ratio were not significantly different between hypertensive and normotensive elderly patients. This might be because of the wide range of normal values in elderly persons due to the various degrees of atherosclerotic changes and other pathophysiologic factors, which might have masked obvious characteristics of hypertension in elderly hypertensives.

Different types of segmental sclerosing glomerular lesions in six experimental models of proteinuria

From 133 to 615 glomeruli were examined in sections of kidneys from each of 60 animals, representing six rodent models of proteinuria. Particular attention was paid to the position of segmental lesions. Lewis rats given sheep anti-rat glomerular basement membrane antibodies had lesions almost exclusively at the glomerulo-tubular junction. Wistar rats on a diet of 24 per cent casein or with subtotal nephrectomy and a diet of 24 per cent soya had lesions mainly at the hilum. Wistar rats given bovine serum albumin had global lesions but virtually no segmental lesions. Wistar rats given puromycin aminonucleoside had lesions at the glomerulo-tubular junction and global mesangial abnormalities shortly after the treatment but later developed segmental lesions at all parts of the glomerulus. Untreated BUF/Mna rats had lesions at the glomerulo-tubular junction early in life but later had lesions at all parts of the glomerulus. Untreated NZB/NZW hybrid mice had various types of glomerulonephritis and also had lesions at the glomerulo-tubular junction. These findings showed that (1) segmental lesions at the glomerulo-tubular junction, or glomerular tip, occur in experimental animals, a fact not previously reported, and these tip changes are a common feature in several different models of proteinuria; (2) hilar segmental lesions are seen in conditions with hyperfiltration of protein; and (3) segmental lesions at various parts of the glomerulus are seen in some models of proteinuria and probably indicate late effects of random toxic damage to the glomerulus. Thus, there are at least three different types of segmental glomerular lesions in experimental animals--tip, hilar, and random--with different morphology and pathogenesis. It is likely that these findings can be extended to human renal diseases with segmental glomerular lesions. This will help to clarify the controversial and unsatisfactory term focal segmental glomerulosclerosis.

Carcinogenicity and toxicity study of m-phenylenediamine administered in the drinking-water to (C57BL/6 x C3H/He)F1 mice

m-Phenylenediamine (m-PDA, CAS: 108-45-2), a component of hair-dye formulations, was administered in the drinking-water to groups of female and male (C57BL/6 x C3H/He)F1 (B6C3F1) mice at concentrations of 0.02 or 0.04% for 78 wk. All the surviving mice were killed after a further 5-7 wk on untreated drinking-water, 83-85 wk after the start of treatment. Survival of the treated mice was similar to that of the corresponding controls. Body weights were significantly lower in high-dose females and males and somewhat lower in low-dose females than in the controls. The incidences of hepatocellular tumours were low to moderate in all male groups and in the control females, but the treated groups had significantly lower incidences than the controls. A few tumours of the lungs, haematopoietic organs and other organs and tissues were observed in all female and male groups. However, there were no statistically significant increases in the incidences of tumours in these organs and tissues in m-PDA-treated mice of either sex. Under the conditions of this study m-PDA showed no carcinogenic potential in either female or male B6C3F1 mice when administered in drinking-water. No non-neoplastic changes attributable to the compound were found in the treated mice, except for the deposition of brown pigment in follicular epithelial cells of the thyroid gland and in macrophages in some organs and tissues, and pigment impregnation of the bronchioli.

[Malignant lymphoma of the thyroid gland]

During the past 14 years, 14 cases involving a malignant lymphoma of the thyroid have been treated at our department. These cases have been histologically reviewed and reclassified, according to the Working Formulation. Four cases involved a low grade malignancy (LGM), 9 cases an intermediate malignancy (IGM), and 4 cases a high grade malignancy (HGM). Thirteen lymphomas were of the B-cell type, and the remaining lymphoma was of the T-cell type. The coexistence of a chronic thyroiditis was noted in 9 cases. Survivors were only found in the LGM and IGM groups. We consider it necessary to treat malignant lymphomas of the thyroid according to the subtype of the Working Formulation.

Nodular development of spontaneous epithelial thymoma in (ACI/NMs x BUF/Mna)F1 rats

The BUF/Mna strain is a high thymoma line of rats, and virtually all rats develop overt thymomas by the age of 40 weeks. To reveal the early morphologic changes in this thymomagenesis, thymuses and thymomas were studied in (ACI/NMs x BUF/Mna)F1 (ABF1) rats, which inherit a thymoma susceptibility gene (Tsr-1) from the BUF/Mna strain. At 50 weeks of age, 18% of ABF1 rats had developed medium to large thymomas, 54% had just began to develop multiple, small round nodules in their involuted thymuses, and the remaining 29% had involuted thymus only. The nodules were, microscopically, composed of cortex-like tissues with a starry-sky pattern, showing a quite similar structure to that of the large macroscopic thymomas of predominantly lymphocytic type seen in 104-week-old ABF1 or BUF-Mna rats. Thus, the nodule was actually a small thymoma. In fact, their epithelial cells often had larger atypical nuclei than those in the adjacent involuted thymus cortex. At 104 weeks of age, the incidences of the medium to large thymomas and the small thymoma nodules in ABF1 rats were 64 and 19%, respectively. These results suggest that the thymoma of ABF1 rats occurs initially as multiple small nodules which develop further into medium to large overt thymomas as a result of growth and fusion.

Cytologic features of ascites in malignant fibrous histiocytoma of the colon

The cytologic features of ascitic fluid in a case of malignant fibrous histiocytoma (MFH) of the colon are described. At autopsy, two solid tumor masses were found around the ascending and transverse colon, accompanied by about 3,000 ml of ascites. Tumor cells had infiltrated diffusely into the outer layers of almost all of the gastrointestinal wall, simulating peritonitis carcinomatosa. Cytologic examination of the ascites revealed various kinds of tumor cells; short spindle-like cells, multinucleated giant cells, and round cells with an invaginated nuclear margin, forming small clusters. These cytologic findings were considered to be very useful in the diagnosis of MFH, especially in cytologic examinations of ascites.

Characteristics of three human gastric cancer cell lines, NU-GC-2, NU-GC-3 and NU-GC-4

Three human gastric cancer cell lines, NU-GC-2, NU-GC-3 and NU-GC-4 were established in vitro from the cancer tissues obtained from 3 patients during surgery. The pathological findings of the gastric tumors of these cases revealed poorly differentiated adenocarcinoma (and partial signet-ring cell carcinoma in the case of NU-GC-4). NU-GC-2 and NU-GC-4 were originally obtained from metastatic paragastric lymph nodes and NU-GC-3 was obtained from a metastatic tumor in the brachial muscle. The cells of NU-GC-2 and NU-GC-3 are polygonal in shape and grow as a monolayer sheet. NU-GC-4 cells, however, are mainly spherical in shape with a few free floating cells. Electron microscopy revealed epithelial characteristics in all 3 cell lines. The average doubling time of NU-GC-2 was 36.1 hours, that of NU-GC-3 was 38.2 hours and that of NU-GC-4 was 29.9 hours. The modal chromosome number of NU-GC-2 was 62, that of NU-GC-3 was 58 and those of NU-GC-4 grown in in vitro and in vivo were 52-54 and 53, respectively. In vitro and in vivo lines of NU-GC-4 were established from the same tumor. These two cell lines are quite similar in morphology, but slightly different in karyotype. The in vitro sensitivity to anticancer agents was highest in NU-GC-4 and lowest in NU-GC-2. Of the anticancer agents, mitomycin C and adriamycin were most effective on the cells of all 3 cell lines.

Intermediate filament reconstitution in vitro. The role of phosphorylation on the assembly-disassembly of desmin

Desmin, the myogenic intermediate filament protein, is a phosphoprotein containing phosphoserine, in vivo. The role of phosphorylation on assembly-disassembly and organization of the desmin filament has remained obscure. We report here on a stable and purified system which enables a biochemical examination of desmin filament assembly and disassembly. Using this in vitro system, we carried out stoichiometrical phosphorylations by purified protein kinases. The extent of polymerization-depolymerization was estimated using procedures related to centrifugation and electron microscopy. The evidence we obtained suggests that disassembly of the desmin filament and inhibition of the NaCl-dependent polymerization of the soluble desmin can reversibly occur with either cAMP-dependent or Ca2+-activated, phospholipid-dependent desmin phosphorylation.

Immunohistological analysis of thymic tumors with PE-35 monoclonal antibody reactive with medullary thymic epithelium

PE-35 mouse monoclonal antibody (MoAb) (IgG1) detecting an epithelial antigen with a molecular weight of 35,000 was characterized serologically. Immunoperoxidase staining and double immunoenzymatic staining showed that PE-35 antigen is predominantly on nonlymphoid cells in the medulla of thymus. By immunoelectron microscopy, thymic epithelial cells in the medulla were positive with PE-35 MoAb, but macrophages, interdigitating reticulum cells, and thymocytes were negative with this MoAb, which demonstrated that PE-35 is a valuable marker for medullary epithelium. Using PE-35 and other MoAbs detecting thymic epithelial antigens (TE-3A, RFD-4, TE-4, and HLA-DR), 25 thymomas were studied, together with 6 other tumors of thymic origin. Among 25 thymomas, all 6 cases of epithelial type and 8 of 14 mixed lymphoepithelial type were positive with PE-35 MoAb, but only one of 5 lymphocytic type was positive. PE-35 antigen has a tendency to be expressed in the cases retaining medullary type thymocytes, with the phenotype of cluster of differentiation (CD) 1-/CD3+/CD6+, and also in the area of medullary differentiation. TE-3A, RFD-4, and TE-4 MoAbs reacted with most thymoma cases regardless of the types. HLA-DR was, however, expressed on a part of thymomas and the phenotype combined with that of PE-35 was as follows: PE-35+/HLA-DR+, 8 cases; PE-35+/HLA-DR-, 8 cases; PE-35-/HLA-DR+, 8 cases; PE-35-/HLA-DR-, one case. The results suggested that thymoma may originate from different subsets and/or different stages of thymic epithelium.

The effect of thymectomy on the development of nephropathy in spontaneous thymoma rats of the BUF/Mna strain

A close relationship was assumed between the developments of nephropathy and thymoma in the previous study, in which the effect of introduction of the rat nude gene was studied in high thymoma BUF/Mna rats. In this paper, the effect of neonatal thymectomy on the development of nephropathy was examined to clarify the relationship between these two lesions in BUF/Mna rats. The average amount of urinary protein excreted from sham-operated and thymectomized BUF/Mna rats was 30.8 +/- 17.1 and 40.0 +/- 20.0 mg/day, respectively, and the number of affected glomeruli per 100 glomeruli 4.9 +/- 1.0 and 5.3 +/- 2.0, respectively. There were no significant differences in the urinary protein content, the number of the affected glomeruli, and immunofluorescence findings. In a control group, ACI/NMs rats exhibited 8.9 +/- 2.6 mg/day protein in urine and 0.8 +/- 0.4% affected glomeruli, which were significantly different from that of sham-operated and thymectomized BUF/Mna rats. These results indicate that nephropathy in BUF/Mna rats results neither from thymoma itself nor from the immunological abnormality secondary to it, and suggest that this lesion might be ascribed to a genetic factors.

Cytogenetic studies on rat thymic lymphomas induced by N-propyl-N-nitrosourea

N-Propyl-N-nitrosourea (PNU) was proved to be a strong leukemogen, which induces myelogenous leukemia or thymic lymphoma in rats. BUF/Mna rats and F344 rats were the strain most susceptible to thymic lymphomagenic activity of PNU. In addition, F1 rats between BUF/Mna and WKY rats were also susceptible to PNU-lymphomagenic activity. In the present experiment, karyotypes of 31 thymic lymphomas induced by PNU in BUF/Mna rats and in F1 rats between BUF/Mna and WKY rats were analysed for chromosomal abnormalities. Although no specific chromosomal abnormalities were observed throughout all lymphomas, del(11q) and dup(2q) were observed frequently in BUF/Mna rat lymphomas. Breakpoints and/or fusion-points were frequently observed in chromosome 11, followed by chromosomes 2, 5 and 6. Trisomy of chromosome 7, on which c-myc oncogene is mapped, was observed in seven cases, and monosomy of chromosomes 12, 18, 19, 20 and X was seen in seven or eight cases each, though these changes were generally observed in minor cell population in each case.

Characteristics of cell lines established from a mixed mesodermal tumor of the human ovary. Carcinomatous cells are changeable to sarcomatous cells

Four clonal cell lines of two types were established from a heterotransplantable mixed mesodermal tumor of the human ovary. Biologic properties of these cell lines (designated CS-C1, CS-S1, CS-S2, and CS-S3) were examined. Cells of one line (CS-C1) had an epithelioid shape and grew in monolayers (C-type). The cells showed alkaline phosphatase activity, stained positively with antikeratin antiserum, and had an ultrastructure with carcinomatous characteristics. Cells of the other three cell lines (CS-S1, CS-S2, and CS-S3) had an irregular shape and grew in multilayers (S-type). Most of the cells did not show alkaline phosphatase activity. They stained, not with antikeratin antiserum, but in fibrillar array with antifibronectin antiserum. Their ultrastructure had sarcomatous characteristics. By low cell density cultures, S-type sublines arose from CS-C1 cell line, but no C-type sublines arose from CS-S1 cell line. These findings may support the theory of the combination tumor as the cytogenesis of mixed mesodermal tumor of the ovary; they also suggest the conversion of carcinomatous cells to sarcomatous cells.

Site-specific phosphorylation induces disassembly of vimentin filaments in vitro

Intermediate filaments are a major component of the cytoskeleton of eukaryotic cells. Although there appear to be at least five distinct classes of these filaments, cells of mesenchymal origin and most cells in culture contain the intermediate filament composed of the subunit protein vimentin. Vimentin exists in a nonphosphorylated as well as in a phosphorylated form, and there is increased phosphorylation of this protein when the filament undergoes marked redistribution in various cells. The role of phosphorylation on assembly-disassembly and organization of the vimentin filament has remained obscure. We report here a stable and purified system allowing biochemical examination of vimentin filament assembly and disassembly. Using this in vitro system, we carried out stoichiometrical phosphorylations, using purified protein kinases. We obtained evidence for site-specific, phosphorylation-dependent disassembly of the vimentin filament.

Sequences responsible for erythroid and lymphoid leukemia in the long terminal repeats of Friend-mink cell focus-forming and Moloney murine leukemia viruses

Despite the high degree of homology (91%) between the nucleotide sequences of the Friend-mink cell focus-forming (MCF) and the Moloney murine leukemia virus (MuLV) genomic long terminal repeats (LTRs), the pathogenicities determined by the LTR sequences of the two viruses are quite different. Friend-MCF MuLV is an erythroid leukemia virus, and Moloney MuLV is a lymphoid leukemia virus. To map the LTR sequences responsible for the different disease specificities, we constructed nine viruses with LTRs recombinant between the Friend-MCF and Moloney MuLVs. Analysis of the leukemia induced with the recombinant viruses showed that a 195-base-pair nucleotide sequence, including a 75-base-pair nucleotide Moloney enhancer, is responsible for the tissue-specific leukemogenicity of Moloney MuLV. However, not only the enhancer but also its downstream sequences appear to be necessary. The Moloney virus enhancer and its downstream sequence exerted a dominant effect over that of the Friend-MCF virus, but the enhancer sequence alone did not. The results that three of the nine recombinant viruses induced both erythroid and lymphoid leukemias supported the hypothesis that multiple viral genetic determinants control both the ability to cause leukemia and the type of leukemia induced.

Human T-lymphoblastoid cell lines with high and low abilities to produce interferon-gamma constitutively and their susceptibilities to interferon

A human T-lymphoblastoid cell line, TCL-Fuj, produces large amounts of interferon (IFN)-gamma constitutively. A variant cell line, 2M, was derived from it. Both cell lines express similar surface antigen markers, but differ in surface morphology. Compared with the parent TCL-Fuj cell line, 2M produced less IFN-gamma constitutively but more in response to IFN inducers. The IFNs produced constitutively and on stimulation with inducers were analyzed by SDS-polyacrylamide gel electrophoresis. In TCL-Fuj cells, the constitutive and induced IFNs consisted of the same molecular species (22K and 39K). In 2M cells, smaller IFNs were produced constitutively (18K and 32K) and induction resulted in a marked increase of 22K molecules. These two cell lines also differed in sensitivity to the antiviral activity of IFN. Other T-lymphoblastoid cell lines, HPB-ALL and TCL-Fuj 4 cells, which did not produce IFN-gamma were permissive for vesicular stomatitis virus (VSV) replication; its growth was markedly suppressed by IFN-gamma and -alpha. TCL-Fuj cells were also permissive for VSV, but were not susceptible to the antiviral effect of the IFNs. In contrast, in 2M cells the multiplication of VSV was restricted; the viral yield was further reduced by the IFNs and increased by treatment with anti-human IFN-gamma serum. Several clonal cell lines derived from TCL-Fuj and 2M cells had characteristics similar to the respective parent cell lines. The growth of both cell lines was not affected by IFN-gamma or by -alpha. The separation of antiviral and anti-proliferative susceptibilities was peculiar to 2M cells unlike other cell lines.

[A case of renal cell carcinoma with the complication of a giant cyst difficult to distinguish from xanthoma]

A case of renal cell carcinoma accompanied by a giant cyst in a 69-year-old male patient is reported. The patient consulted a physician in our Hospital for bellyache on the left abdomen. Because giant cyst in the left kidney and intracystic hemorrhage were suspected by computed tomography diagnosis, the patient was transferred to the Department of Urology, As a tumor-like mass was detected in the cyst by ultrasound echo diagnosis, transperitoneal extirpation of the left kidney was conducted on May 8, 1985. At operation, a giant unilocular cyst covered with hypertrophic fibrous capsule including much coagula was observed. The inner wall of the cyst was covered with many deeply yellow torous lesions of sizes ranging from those of a wheat grain to thumb. Histologically, the lesions consisted of a cell group supposedly of histiocyte origin accompanied by cellular infiltration of lymph cells, and xanthoma was deeply suspected. However, as it was difficult to distinguish from the clear cell subtype of renal cell carcinoma, examination by an electron microscope was conducted and the final diagnosis of renal cell carcinoma was made. The post-operative course of the patient was good and no recurrence or cancer metastasis was observed as of January, 1986.

Argyrophil cells in normal endometrial glands

Normal endometrium from one hundred normal cases were examined histologically, using sections stained with the Grimelius method. Endocrine cells were demonstrated in 4 cases. Immunohistochemically, these cells were positive for anti-serotonin and anti-somatostatin antisera. Argyrophil granules were also observed in supranuclear or subnuclear regions of glandular cells in 17 cases, and argyrophilia was present in the apical region including the brush borders or microvilli of glandular cells in 6 cases. In these latter 23 cases argyrophilia seemed to be nonspecific, having no relation to endocrine type secretory granules, judging from the electronmicroscopic observations on the silver-impregnated sections. The presence of endocrine cells and the pattern of argyrophilia in glandular cells were similar to those found previously in endometrial glandular adenocarcinomas with argyrophil cells. This is the first report on the occurrence of endocrine cells in normal endometrial glands.

Possible single dosage effects of the nude gene: suppression of spontaneous development of thymoma and nephropathy in BUF/Mna-rnu/+ rats

Single dosage effects of the rat nude gene (rnu) on spontaneous development of epithelial thymoma, muscle atrophy and nephrotic syndrome were studied by comparing littermates of rnu /+ and +/+ rats on a high thymoma strain, BUF/Mna, background. Heterozygous rnu/+ rats had a significantly smaller thymus than the +/+ littermates at 6 weeks of age. The incidence of thymoma at 12 months of age was extremely low in the female rnu/+ rats (3%) as compared with that of the +/+ rats (94%). Development of the nephrotic syndrome but not of the muscle atrophy was also suppressed in the heterozygotes. The results suggest that a recessive mutant gene, rnu, in a single dosage, interfered with critical steps of the disease processes of the thymoma and nephrotic syndrome in BUF/Mna-background rats.