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Biomedical subjects

T Tokiwa

Publications and source records attributed to T Tokiwa.

At least 37 records · Page 2Linked to original sources

Effects of laminin and collagen type I on the morphology and secretion of proteins in human hepatoblastoma and hepatoma cell lines.

The effects of laminin (LAM) and collagen type I (C-I) on human hepatoblastoma (HuH-6) and hepatoma (HuH-7) cell lines were investigated. C-I was superior to LAM in supporting the attachment of the cells, especially of HuH-6, to plastic surfaces. No effect of LAM and C-I on cellular morphology was recognizable by phase contrast microscopy. By scanning electron microscopy (SEM), much more microvilli were found on the cell surface of HuH-6 on LAM substrate than on C-I substrate. In HuH-7 cells, however, these microvilli were rarely found on either LAM substrate or C-I substrate. The gel profile of the proteins secreted by HuH-6 and HuH-7 cells was not affected by the culture substrate except for the major band, though the amount of alpha-fetoprotein (AFP) secreted was larger when the cells were cultured on LAM substrate than on C-I substrate. These results indicate that the ability of LAM or C-I to enhance attachment is different from that to enhance AFP production or microvilli expression in HuH-6 cells and probably in HuH-7 cells.

Carcinoma, Hepatocellular↗

Pharmacokinetics of recombinant human granulocyte colony-stimulating factor studied in the rat by a sandwich enzyme-linked immunosorbent assay.

A sandwich enzyme-linked immunosorbent assay for the measurement of recombinant human granulocyte colony-stimulating factor (rhG-CSF) in rat serum was developed using anti-rhG-CSF Fab'-horseradish peroxidase conjugate. This assay method measured rhG-CSF in rat serum with greater sensitivity than a bioassay. Also, a good agreement between enzyme-linked immunosorbent assay and bioassay was observed with rat serum samples after administration of rhG-CSF. The pharmacokinetics of rhG-CSF were investigated in male Sprague-Dawley rats using enzyme-linked immunosorbent assay at four different doses from 1 to 100 micrograms/kg. For i.v. administration, the serum rhG-CSF concentration-time curves were best described by a biexponential equation. Over the dose range studied, no changes in volume of distribution were observed. However, a reduction in rhG-CSF clearance and prolongation of half-life (beta) were noted as the dose of rhG-CSF increased. For s.c. administration, a markedly lower serum peak rhG-CSF concentration was observed, but after 2 to 3 hr, rhG-CSF concentration was higher than that following i.v. administration. Administration s.c. also caused nonlinear increases in the serum concentration. Bioavailability after s.c. administration was 0.509 to 0.704.

Animals↗

[Tissue culture course of a human hepatoma cell line].

A cell line, HuH-33 was cultured in vitro from a patient with hepatocellular carcinoma. This cell line has been in continuous culture over 12 month period with slow growth potential. HuH-33 was composed spindle-or polygonal-shaped cells as a major population. Chromosome number of the cells were widely distributed even in the primary culture. HuH-33 was transplantable into nude mice and secreted alpha-fetoprotein, albumin, beta 2 microglobulin, ferritin and tissue polypeptide antigen.

Aged↗

Effects of serum and serum-derived factors on the growth and production of alpha-fetoprotein and albumin by human hepatoma cell lines.

A serum-free culture system of human hepatoma cell lines (HuH-6 and HuH-7) was used to investigate the activity of bovine serum (BS) and of serum-derived factors on the growth and production of alpha-fetoprotein (AFP) and albumin. At higher concentrations, dialyzed BS was inhibitory to the growth of HuH-6 and caused reduction of the level of AFP production by the cells. AFP and albumin levels in HuH-6 and HuH-7 were reduced or unchanged by fetuin, bovine serum albumin (BSA) and transferrin (TF), although no cytotoxicity was shown by any of them. Commercial preparations of platelet-derived growth factor exhibited cytotoxicity to HuH-6 and HuH-7 and induced a decrease of AFP and albumin levels in a dose-dependent manner. Transforming growth factor (TGF-beta) exhibited no cytotoxicity to HuH-6. AFP levels in HuH-6 were unchanged with 1000 pg/ml TGF-beta, but albumin levels were decreased. TGF-beta at a concentration of 1000 pg/ml was cytotoxic to HuH-7 and AFP levels were a little increased. Albumin levels, however, were unchanged. Following exposure to cycloheximide, AFP and albumin levels in HuH-6 were inhibited.

Albumins↗

Alpha-fetoprotein-producing capacity, chromosomal and morphological properties in human hepatoma cells treated with various chemotherapeutic agents.

Alpha-fetoprotein (AFP)-producing capacity and some other properties of human hepatoma cell lines treated with chemotherapeutic agents, such as mitomycin C, Adriamycin, cisplatinum, and 5-fluorouracil were investigated. In the case of hepatoma cells that can be grown in culture following treatment with chemotherapeutic agents, their AFP-producing capacity was almost equal to that of untreated control cells with a few exceptions. On the other hand, in the case of similarly treated hepatoma cells that cannot be grown in culture, their AFP-producing capacity was quite different from that of untreated control cells. Under these conditions chromosomal and morphological aberrations were also observed in the treated cells. The present study shows that AFP-producing capacity of hepatoma cells can be changed by chemotherapeutic agents, probably through chromosomal mutation.

Antineoplastic Agents↗

A new human cholangiocellular carcinoma cell line (HuCC-T1) producing carbohydrate antigen 19/9 in serum-free medium.

A human cholangiocellular carcinoma cell line, HuCC-T1, was established in vitro from the malignant cells of ascites of a 56-yr-old patient. Histologic findings of the primary liver tumor revealed a moderately differentiated adenocarcinoma. Tumor cells from the ascites have been cultured with RPMI 1640 medium containing 0.2% lactalbumin hydrolysate and the cultured cells grew as monolayers with a population doubling time of 74 h during exponential growth at Passage 25. They had an epithelial-like morphology and were positive for mucine staining. Ultrastructural studies revealed the presence of microvilli on the cell surface and poorly developed organelles in the cytoplasm. The HuCC-T1 cell was tumorigenic in nude mice. The number of chromosomes in HuCC-T1 ranged from 61 to 80. These human cholangiocellular carcinoma cells in serum-free medium secreted several tumor markers, including carbohydrate antigen 19/9, carbohydrate antigen 125, carcinoembryonic antigen, and tissue polypeptide antigen. The carbohydrate antigen 19/9 secretion level of HuCC-T1 cells cultured in RPMI 1640 medium with 1% fetal bovine serum was sixfold higher than that with 0.2% lactalbumin hydrolysate. These findings suggest that HuCC-T1 will provide useful information to clarify the mechanism of tumor marker secretion and tumor cell growth in the human cholangiocellular carcinoma.

Adenoma, Bile Duct↗

Effects of chemotherapeutic agents on alpha-fetoprotein secretion and growth of human hepatoma cell lines in vitro.

The effects of various chemotherapeutic agents on alpha-fetoprotein (AFP) secretion and growth of human hepatocellular carcinoma and hepatoblastoma cell lines were investigated in vitro. It was found that there was a high correlation between hepatoma cell number and AFP secretion after treatment and that the amount of AFP secreted per cell per 72 h was not affected with therapeutically achievable concentrations. These results suggest that serum AFP level in patients with hepatomas does not correlate with the size of whole tumour but with that of viable tumour mass, and that AFP-secreting capacity of tumour cells in the mass is kept unchanged after chemotherapy.

Antineoplastic Agents↗

Alkaline phosphatase expression in human cell lines derived from primary hepatomas.

Isozyme patterns of alkaline phosphatase (ALP) were electrophoretically examined in human cell lines derived from one hepatoblastoma, five hepatocellular carcinomas (HCCs) and two cholangiocellular carcinomas. Most of the cell lines tested had a liver-type ALP isozyme. In addition, an abnormal ALP isozyme, which was similar to variant ALP, was detected in one hepatoblastoma and two HCC cell lines. One HCC cell line of these variant-like ALP-positive cell lines was alpha-fetoprotein (AFP)-negative. These findings suggest that variant-like ALP may be useful for the identification of human hepatoma cell lines, especially in AFP or albumin-negative cell lines.

Alkaline Phosphatase↗

Examination of HeLa cell contamination of human cell lines derived from primary hepatomas using glucose-6-phosphate dehydrogenase and lactate dehydrogenase isozymes.

Isozyme patterns of glucose-6-phosphate dehydrogenase (G6PD) and lactate dehydrogenase (LDH) in human cell lines derived from primary hepatomas were compared with those in HeLa cells. Some cell lines derived from primary hepatomas having type B G6PD showed one or two isozymes of LDH. On the other hand, HeLa cells having type A G6PD showed four LDH isozymes. These findings suggest that not only G6PD, but also LDH may be useful for the detection of HeLa cell contamination of a culture in some cases.

Carcinoma, Hepatocellular↗

Effect of various factors and substrates on the growth of a human hepatoblastoma cell line, HuH-6 in a serum-free medium.

The effect of various factors and substrates on the growth of a human hepatoblastoma cell line, HuH-6, which was inoculated at low density in a serum-free medium was examined. Several supplements were required to enhance cell growth of HuH-6. These included cholera toxin (CT), glucagon (Glu) and selenium (Se). Type IV collagen (C-IV) provided the most conductive environment tested for cell growth. These results suggest that CT, Glu, Se, and C-IV are important stimulators for the continuous growth of HuH-6 in a serum-free medium at low density.

Animals↗

Pharmacokinetics and pharmacodynamics of recombinant human granulocyte-colony stimulating factor after intravenous and subcutaneous administration in the rat.

The pharmacokinetics of recombinant human granulocyte-colony stimulating factor (rhG-CSF) (produced by Kirin Brewery Co., Ltd.) in sera was studied after i.v. and s.c. administration into male Sprague-Dawley rats. Arterial blood samples were taken to determine the rhG-CSF concentrations by measuring its activities using a modified [3H]thymidine assay. After the i.v. dose of 100 micrograms/kg, the half-lives were 25 (alpha) and 102 min (beta). Subcutaneous administration at the 100-micrograms/kg dose resulted in a lower peak serum level but, after 2 hr, rhG-CSF level after the s.c. dose was higher than that of the i.v. dose. The bioavailability of the s.c. dose of 100 micrograms/kg was 78%. The effect of rhG-CSF administration in rats was a specific activity on the neutrophil lineage with increase of neutrophils in peripheral blood. Intravenous and s.c. administration of rhG-CSF had identical effects on the peak neutrophil counts in peripheral blood but, at 24 hr after injection, neutrophil counts after the s.c. dose was greater than that of the i.v. dose. These results indicate the close relationship between pharmacokinetics and pharmacodynamics of rhG-CSF in the rats.

Animals↗

[Studies on AFP-producing capacity and some other properties of human hepatoma cells treated with various anticancer drugs].

The effect of various anticancer drugs on alpha-fetoprotein (AFP) secretion and some other properties of human hepatoma cells was investigated in vitro with the following results. (1) There was a high correlation between AFP secretion and cell number after treatment of human hepatoma cells with anticancer drugs and the amounts of AFP secreted per 10(4) cells per 72 hours (AFP-secreting capacity) were not affected within therapeutically achievable concentrations (TAC). (2) The AFP-secreting capacity was affected with some exceptions in the cells treated with higher concentration of drugs than TAC. Furthermore, chromosomal and morphological aberrations in the similarly treated cells, were also observed, suggesting the relationship between the change of AFP-producing capacity and that of some other properties.

Antineoplastic Agents↗

Establishment and characterization of a cell line from a human cholangiocellular carcinoma.

A cell line, HuH-28, was established in vitro from a patient with cholangiocellular carcinoma (CCC). This cell line has grown slowly, revealing a doubling time of approximately 80 h, and the serial passages were carried out 20 times within 10 months. Light microscopy revealed spindle and polygonal morphology of the cells. Chromosome number of the cells were distributed near the hypotriploid region at passages 3 and 14. HuH-28 cells were not transplantable into nude mice, but secreted some tumor markers including alkaline phosphatase (ALP), gamma glutamyltranspeptidase (GGT), beta 2-microglobulin (BMG), ferritin, elastase-1, and tissue polypeptide antigen (TPA). This HuH-28 cell line will represent a good model for the investigation of carcinogenesis, histogenes, and diagnosis of CCC.

Adenoma, Bile Duct↗

Isolation of clones from T24 cells and test of their sensitivity to adriamycin.

Two single cell clones, CL3 and CL7, were developed from T24 cells. CL3 had abundant cytoplasmic granules, while CL7 did not have as much. CL3 and CL7 exhibited a modal number of chromosomes at 69 and 74, respectively. CL7 had a higher growth rate than CL3, as indicated by in vitro cell growth, plating efficiency, and growth of the tumors produced in nude mice. CL3 was slightly susceptible to adriamycin toxicity as compared to CL7.

Animals↗

Effects of various substrates on human hepatoblastoma and hepatoma cell culture.

The effects on human hepatoblastoma (HuH-6) and hepatoma (HuH-7) cell lines of collagen type I (CI), type IV (CIV), fibronectin (FN) and laminin (LAM) were investigated. CI and CIV promoted almost equally the attachment of both cell lines more strikingly than did FN or LAM. CI and CIV were also superior to FN or LAM in supporting the growth of HuH-6. These substrates, however, had no appreciable effect on the growth of HuH-7. The amount of alpha-fetoprotein (AFP) and albumin secreted in HuH-6 was found to be higher on FN- and LAM- coated substrates than on the other matrix material- coated ones. HuH-7 exhibited increased levels of AFP on LAM- coated substrates 4 days after plating. These results indicate that the ability of extracellular matrix materials to enhance attachment and/or growth is different from that to enhance AFP and albumin production in HuH-6 and probably in HuH-7.

Carcinoma, Hepatocellular↗

[Effects of various factors on the growth and function of a human hepatoblastoma cell line, HuH-6--an approach for serum-free cell culture].

The effects on a human hepatoblastoma cell line (HuH-6) of serum and Ca2+ were investigated. A higher concentration of serum reduced the production of alpha-fetoprotein, whereas Ca2+ enhanced that of both albumin and alpha-fetoprotein. In view of these facts, a serum-free medium using RPMI-1640 supplemented with lactalbumin hydrolysate, epidermal growth factor, hydrocortisone, insulin, chrelatoxine, glucagone and selenium was then developed. Collagen type IV was superior to collagen type I, laminin, fibronectin and plastic in supporting the growth of HuH-6 in the serum-free medium. Higher amounts of both albumin and alpha-fetoprotein were secreted in HuH-6 cultured in serum-free medium than in serum-supplemented medium.

Blood↗

[Establishment and characterization of a human cholangiocellular carcinoma cell line].

A cell line, HuH-28 was established in vitro from a patient with cholangiocellular carcinoma (CCC). This cell line has been in continuous culture over 10 month period with slow growth potential. HuH-28 was composed of spindle-shaped cells as major population besides a small percentage of polygonal-shaped cells. Chromosome number of the cells were distributed near the hypotriploid region on the 3rd passage. HuH-28 cells were not transplantable into nude mice, but secreted some tumor markers including alkaline phosphatase (ALP), gamma glutamyltranspeptidase (GGT), beta 2-microglobulin (BMG), ferritin, elastase-1 and tissue polypeptide antigen (TPA). This HuH-28 cell line will represent a good model for the investigation of carcinogenesis, histogenesis+ and diagnosis of CCC.

Adenoma, Bile Duct↗