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Biomedical subjects

Y Nio

Publications and source records attributed to Y Nio.

At least 73 records · Page 4Linked to original sources
PubMed1992

Experimental chemotherapy for xenograft cell lines of human bile duct and gall bladder cancers in nude mice.

Most biliary tract cancers are advanced and inoperable when first diagnosed. Even if surgery can be performed, the postsurgical prognosis of these diseases is poor. In the present study, we investigated effective chemotherapies for a human bile duct cancer xenograft cell line (undifferentiated carcinoma, BDC-SN) and a gall bladder cancer xenograft cell line (well-differentiated adenocarcinoma, GBC-GN), which were transplanted into nude mice. Eight anticancer agents (CDDP, 5-FU, VDS, MMC, ADR, EPIR, CQ, and VP-16) and their various combinations were evaluated at 2-4 times the clinical dose. When used singly, CDDP, 5-FU, and VDS were effective against BDC-SN, and only CDDP was effective against GBC-GN. Among the various 2-agent combinations, CDDP + 5-FU was the most effective against both BDC-SN and GBC-GN. However, 3-agent combinations consisting of CDDP + 5-FU + another agent were less effective than the CDDP + 5-FU double regimen and caused significant loss of weight as well as high mortality. These results suggest that CDDP + 5-FU may be the most useful regimen against biliary tract cancers in clinical application.

Adenocarcinoma↗
PubMed1992

Comparative effects of a recombinant and a mutein type of granulocyte colony stimulating factor on the growth of Meth-A fibrosarcoma with 5-fluorouracil chemotherapy.

The present study was designed to evaluate the effects of a recombinant human G-CSF (rhG-CSF) and a mutein G-CSF (KW-2228) on leucopenia and tumor growth in mice treated with 5-fluorouracil (5-FU). In normal mice, the number of leucocytes (white blood cell, WBC) reached the peak 12 hours after a single injection of either type of G-CSF and decreased to the normal level after 24 hours. Daily administration induced a continuous increase in the WBC count, however, administrations at intervals did not. Meth-A fibrosarcoma was subcutaneously inoculated into the backs of syngeneic BALB/c mice. The mice were treated with 5-FU alone or with G-CSFs. Chemotherapy with 5-FU alone resulted in leucopenia and an insignificant inhibition of tumor growth. The conjunctive administration of G-CSFs with 5-FU resulted in a significantly augmented inhibition of tumour growth, and leukopenia was not seen. This augmenting effect was more prominent with KW-2228. These results suggest that in 5-FU chemotherapy G-CSFs may be beneficial in restoring the number of leucocytes from leucopenic state and in augmenting the tumor inhibitory effect. Furthermore, KW-2228 may be more beneficial than the natural type rhG-CSF.

Amino Acid Sequence↗
PubMed1992

Immunomodulation by orally administered protein-bound polysaccharide PSK in patients with gastrointestinal cancer.

The present study was designed to assess the effects of the protein-bound polysaccharide PSK on the immunological status of patients with gastrointestinal cancer. Twenty-nine gastric and 18 colorectal cancer patients were randomly assigned to either the control or PSK group. Patients in the PSK group were given 3.0 g of PSK orally before surgery, either daily or every other day. Patients in the control group received no PSK. The data of peripheral blood lymphocytes (PBL) were compared before and after administration of PSK, and those of the regional node lymphocytes (RNL) were compared between the control and the PSK group. The results indicate that the effects of PSK were significantly influenced by the duration of administration, but not by the frequency of administration. In the patients belonging to the short term PSK group (administration less than 14 days), the response of the PBL to PSK and Con A become significantly stronger compared to before the administration of PSK, whereas the cytotoxicity against K562 and KATO-3, and the proportion of CD16+ cells increased significantly in those patients belonging to the long term PSK group (greater than or equal to 14 days). In addition, the proportion of CD9 + 11b + suppressor T cells decreased in the RNL of the short term PSK group, whereas the proportion of CD4 + Leu8 - helper T cells in the RNL increased in the long term PSK group. These results suggest that the oral administration of PSK leads to the suppression of suppressor cells in the RNL.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic↗
PubMed1992

A comparative study on immunosuppressive effects of cyclosporin A and FK 506 on peripheral blood lymphocytes in dogs.

Immunosuppressive effects of cyclosporin A (CsA) and FK 506 (FK) on peripheral blood lymphocytes were studied in dogs in respect to mixed lymphocyte reaction, proliferative responses to recombinant interleukin-2 (rIL-2), phytohemagglutinin (PHA) and concanavalin-A (Con-A); phenotypes of OKIa1, CD3, CD8 and surface IgM; cytotoxic activity against xenogeneic tumor cells. CsA (2.0 or 5.0 mg/kg, intravenously) or FK (0.16 mg/kg, intramuscularly) was given to mongrel dogs every morning for serial 21 days. The blood concentrations of CsA, measured as trough levels by fluorescence polarization method, ranged from 37 to 350 ng/ml in dogs administered at 2.0 mg/kg and from 170 to 894 ng/ml in dogs administered at 5.0 mg/kg during treatment, respectively. In dogs treated with FK at a dose of 0.16 mg/kg, the drug concentrations in the plasma during treatment ranged from 0.16 to 1.8 ng/ml. Mixed lymphocyte reaction and proliferative responses to rIL-2, PHA and Con-A, which were declined by CsA, were not affected by FK. In contrast, the proportion of OKIa1+ cells was not affected by CsA, whereas FK decreased the proportion of OKIa1+ cells progressively during the course of treatment. Cytotoxic activity was suppressed by both CsA and FK. These results possibly indicate that CsA and FK exert their immunosuppressive effects via different mechanisms.

Animals↗
PubMed1992

Commitment reversion model of unrestricted cell growth.

Through the analysis of accumulated experimental data of cell growth, a model of unrestricted cell growth is presented here. This model is based hypothetically on the cellular commitment to senescence as in the previously presented commitment theory. Cells are divided into 3 types, namely uncommitted cells, committed cells and terminal cells. The division of an uncommitted cell produces an uncommitted cell itself and a committed cell of the first generation. This committed cell goes through a limited number of cell divisions until the cells become non-dividing terminal cells. It is hypothesized that during a committed cell division, there is a very small probability that an uncommitted cell may be generated. With computer simulations, it is estimated that a committed cell of the first generation may divide around 30 times until they become non-dividing terminal cells, and that the probability of an uncommitted cell regeneration for each committed cell division may be 2(-H). This hypothesis may possibly clarify some aspects of the biological phenomena of cell growth, which can not be explained by the previous commitment theory, such as the growth pattern of cultured diploid cells, cancer initiation and promotion, and cancer progression and metastasis.

Animals↗
PubMed1992

Effect of PSK and its subfractions on peripheral blood lymphocytes mediated cytotoxicity against urinary bladder tumor cells.

Our previous studies have indicated that the protein-bound polysaccharide Kreha (PSK) enhances the cytotoxic activity of peripheral blood lymphocytes (PBL) against the T24 human urinary bladder tumor cell line in patients with bladder tumor. Since PSK consists of a mixture of various kinds of protein-bound polysaccharides, the present study was designed to examine which subfractions of PSK mediated the enhancement of cytotoxicity. When PSK was separated according to size, treatment of PBL with the 50 kilodalton (kd) or less fraction killed T24 cells more efficiently than unfractionated PSK-treated PBL. The higher molecular weight fractions did not enhance killing above the control level. PSK was fractionated on a diethylaminoethyl (DEAE)-cellulose column to obtain a protein rich fraction that absorbed onto the column and a polysaccharide rich fraction that did not. PBL treated with the polysaccharide rich fraction were able to kill T24 cells more effectively than unfractionated PSK-treated PBL. The protein rich fraction had no effect on the killing. Further fractionation of the polysaccharide rich fraction was performed by differential precipitation with ammonium sulfate. PBL treated with the precipitated fraction at 70-80% saturation (PSK Fraction D) enhanced cytotoxicity equal to that of the polysaccharide rich fraction. Treatment of PBL with the other fractions did not augment the cytotoxicity. These enhancement by PSK fractions were observed in healthy donors and also in patients with bladder tumor. An increase of the proliferative response of PBL to PSK Fraction D as well as unfractionated PSK was observed. Treatment of PBL with PSK Fraction D had no effect on the proportion of PBL binding to T24 cells, thus suggesting a post-binding effect. The structure of PSK Fraction D as inferred from the results of methylation analysis was mainly an alpha-glucan. These results demonstrate that PSK mediated enhancement of cytotoxicity and proliferation of PBL may be largely due to an alpha-glucan of less than 50 kd.

Adult↗
PubMed1992

Modulation by cis-diamminedichloroplatinum (II) of the susceptibilities of human T24 lined and freshly separated autologous urinary bladder transitional carcinoma cells to peripheral blood lymphocytes and lymphokine activated killer cells.

The effects of cis-diamminedichloroplatinum (II) on the susceptibilities of human T24 lined and freshly separated autologous urinary bladder transitional carcinoma cells to lysis by peripheral blood lymphocytes of patients with urinary bladder cancer was analysed in a 12-hour 51Cr release assay. Treatment of T24 cells with cis-diamminedichloroplatinum (II) at 10 micrograms./ml. for three hours enhanced their susceptibility to peripheral blood lymphocytes and lymphokine activated killer cells. Kinetics studies demonstrated that the enhancement of their susceptibility became noticeable by three hours and continued until 12 hours. The susceptibilities of autologous tumor cells to both large granular lymphocytes and T lymphocytes were also enhanced by treatment of them with cis-diamminedichloroplatinum (II). There was no significant difference in the number of peripheral blood lymphocytes binding to cis-diamminedichloroplatinum (II)-treated T24 cells as compared with untreated T24 cells. Treatment of T24 cells with mitomycin C did not change their natural killer sensitivity. Pretreatment of T24 cells with cis-diamminedichloroplatinum (II) and lysosomotrophic agents (L-leucin-methyl-ester or chloroquine) reduced the enhancement of their susceptibility to natural killer cells by cis-diamminedichloroplatinum (II) alone. On the other hand, pretreatment of peripheral blood lymphocytes with cis-diamminedichloroplatinum (II) had no influence on the cytotoxicity against T24 cells. These results indicate that cis-diamminedichloroplatinum (II) may have an augmenting effect on the susceptibility of tumor cells to the cell-mediated cytotoxicity partly through a modification of cell membrane independently of its antimetabolic activity and this modification may be one of the possible mechanisms responsible for tumor regression after chemotherapy with cis-diamminedichloroplatinum (II).

Aged↗
PubMed1992

A comparative study of the antitumor activities of 5'-deoxy-5-fluorouridine and its prodrug trimethoxybenzoyl-5'-deoxy-5-fluorocytidine (Ro09-1390) on human digestive organ cancer xenograft lines transplanted into nude mice.

5'-Deoxy-5-fluorouridine (5'-DFUR) is one of the oral fluoropyrimidines widely used in the treatment of gastric, colorectal and breast cancers in Japan. 5'-DFUR is converted to 5-fluorouracil by pyrimidine nucleoside phosphorylase in the tumor. 5'-DFUR has toxic effects on the intestine and may cause severe diarrhea. Trimethoxybenzoyl-5'deoxy-5-fluorocytidine (Ro09-1390) is a prodrug of 5'-DFUR, which was developed to reduce the intestinal toxicity of 5'-DFUR. The present study was designed to assess the antitumor activity and spectrum of Ro09-1390, and to compare its efficacy with that of 5'-DFUR. Six digestive organ cancer xenograft lines (two gastric, one esophageal, one colorectal, one gall bladder and one bile duct cancers) were s.c. transplanted into nude mice. The agents were orally administered daily for 14 days at doses of 0.08-0.64 mmol/kg (1-8 times the maximal clinical dose of 5'-DFUR). Both 5'-DFUR and Ro09-1390 significantly inhibited the growth of two gastric cancer lines, and the IC50's for Ro09-1390 in both lines were lower than the respective values for 5'-DFUR. The esophageal, colorectal, gall bladder and bile duct cancer lines, however, were resistant to both agents. 5'-DFUR at 0.64 mmol/kg significantly inhibited the growth of these cancers, but with high mortality, and most mice receiving this dose died within 14 days after the start of therapy, suffering from severe diarrhea and body weight loss. Ro09-1390 at the same dose resulted in low mortality, but evidenced similarly low antitumor activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Hepatectomy accelerates the growth of transplanted liver tumor in mice.

To study the effect of hepatectomy on the growth of liver tumor, Shionogi Carcinoma 42, a mammary tumor, was transplanted into the liver of mice which had undergone 40% hepatectomy. The liver tumor and the number of pulmonary metastases in hepatectomized mice were significantly larger than those in nonhepatectomized mice. Responses to lectins and IL-2, subpopulations, and cytotoxicity to YAC-1 and P815 cells of splenocytes were assessed to evaluate immunological status. At the initial phase after hepatectomy and tumor transplantation into the remaining liver, NK activity transiently increased, and function of B and T cells, especially of helper T cells, decreased, while B-cell function recovered beyond normal levels in a later phase. These results suggest that liver may play an important immunological role and that the immunological modification after hepatectomy may be responsible for the accelerated growth of liver tumor. Accordingly, some adjuvant immunotherapy may be recommended for the prevention of recurrence after hepatectomy for liver tumor.

Alanine Transaminase↗
PubMed1991

Problems in the definition and treatment of early gastric cancer.

Radical operation with extensive dissection of lymph nodes (R1, 48 patients; R2, 196 patients; R3, one patient) was performed in 245 out of 247 patients with early gastric cancer. The 5-year survival rate was only 73.2 per cent in the 34 patients with lymph node metastases (31.8 per cent). Analysis of factors influencing recurrence revealed that not only lymph node metastases but also the depth of cancer invasion could affect prognosis in early gastric cancer. This study suggests that radical operation with complete dissection of the first and second group of lymph nodes (R2 resection) is a safe and appropriate treatment even for early gastric cancer. We propose that the definition of early gastric cancer be modified to 'carcinoma with invasion confined to the mucosa or submucosa and without evidence of lymph node metastases'.

Female↗
PubMed1991

Effects of splenectomy on pulmonary metastasis and growth of SC42 carcinoma transplanted into mouse liver.

The carcinoma SC42 was transplanted into the liver of its syngeneic mice DS, and the immunological integrity of the spleen and the effects of splenectomy on the growth and pulmonary metastasis of the liver tumor were assessed. On day 7 after liver tumor transplantation, the natural killer (NK) activity of the splenocytes was significantly elevated; it subsequently decreased at a later stage of the tumor. The response of the splenocytes to PHA and Con-A decreased significantly from the early stage of the tumor. However, the mixed lymphocyte-tumor cell reaction increased significantly from day 14 to day 28. The survival rate of the mice, which had undergone simultaneous splenectomy and liver tumor transplantation, was significantly lower than that of sham-operated control mice. The number of pulmonary metastases in splenectomized mice was significantly greater than in the control mice. There was, however, no difference between the two groups in the weight of the liver tumor. By contrast, splenectomies performed 14 days before or 14 days after tumor transplantation had no significant influence on the survival of the mice. Splenectomies performed on day 0 and on day 3 after tumor transplantation significantly increased the number of pulmonary metastases. Furthermore, the intravenous injection of anti-asialo GM1 antisera on day 0 and day 3 significantly increased the number of pulmonary metastases, but injection of anti-Thy 1.2 antisera had no effect. These results suggest that splenic NK cells may play an important role in the suppression of pulmonary metastasis at early stages of the liver tumor.

Animals↗
PubMed1991

Combining independently effective anticancer agents may not augment the independent antitumor effects: a study using human digestive organ cancer xenograft lines in nude mice.

Five human digestive organ cancer xenograft lines were subcutaneously transplanted in nude mice, and 7 anticancer agents (ACAs) were intravenously administered singly or in combinations at 4 times the standard clinical doses. Cisplatin (P) was effective in 4 lines and 5-fluorouracil (F) was effective in 3 lines. A total of 8 combinations with 2 effective ACAs were assessed in 4 lines and only 1 combination (FP) resulted in an augmented antitumor effect in a single line. A total of 11 combinations with 1 effective ACA plus 1 ineffective ACA were assessed in 2 lines, and only 1 combination (F + carboquone [CQ; Esquinon]) resulted in an augmented effect in a single line. A total of 5 combinations with independently ineffective ACAs were assessed in 1 line, and 1 combination (FP) resulted in augmented antitumor activity. No 2-ACA combinations showed enhanced side effects. Two combinations with 3 effective ACAs were assessed in 2 lines and 1 combination (FP + mitomycin C) resulted in an augmented effect with a greater mortality rate. A total of 12 combinations with both effective plus ineffective ACAs were assessed in 2 lines, and 3 combinations (FP + Adriamycin or FP + CQ or FP + etoposide) resulted in an augmented effect in 1 line with enhanced side effects. These results indicate that the combination of independently effective ACAs does not always cause an augmented antitumor effect, and may sometimes result in augmented side effects. According to this study, the 3-ACA combinations with FP + 1 effective agent appear to be the best regimens for digestive organ cancer.

Animals↗
PubMed1991

In vitro immunomodulating effect of protein-bound polysaccharide, PSK on peripheral blood, regional nodes, and spleen lymphocytes in patients with gastric cancer.

PSK, a protein-bound polysaccharide, has been widely used for cancer immunotherapy in Japan. However, the mechanism of its immunomodulatory effect has not been fully clarified. In the present study the in vitro effect of PSK on the lymphocytes of patients with gastric cancer was studied. Culturing lymphocytes with PSK at 5-100 micrograms/ml increased the level of DNA synthesis, and augmented the cytotoxicities against K562 and KATO-3. Flow-cytometric analysis also showed an increase in the proportion of interleukin-2 (IL-2)-receptor-positive cells after the lymphocytes were cultured with PSK. However the cytotoxicity of cells cultured with PSK was not augmented by the addition of recombinant interferon gamma (rIFN gamma) and rIL-2. Further experiments using fractionated PSK showed that its biological action is present mainly in fractions having molecular masses greater than 10(5) Da. However, these immunomodulations were not seen in all patients. These results suggest that the susceptibility of lymphocytes to PSK may be different in each patients, and that the immunomodulation by PSK may be mediated by mechanisms independent of IFN and IL-2.

Adjuvants, Immunologic↗
PubMed1991

In vivo effects of human recombinant tumor necrosis factor alone and in combination with other biological response modifiers on human digestive organ cancer xenografts transplanted in nude mice.

The present study was designed to evaluate the effect of rTNF alone or in combination with other BRMs on human digestive organ cancers. Six kinds of human digestive organ cancer xenografts (esophageal, stomach, colonic, pancreatic, bile duct, and liver cancers: EC-YO, GC-YN, CC-KK, PC-HN, BDC-SN and Li-7, respectively) were transplanted in nude mice, and rTNF was administered at 10(3), 5 x 10(3), or 10(4)U/head directly into the tumor 3 times a week for 2 weeks. EC-YO was the most sensitive to rTNF, and intratumoral administration of rTNF at 10(3) U/head caused tumor regression. PC-HN, CC-KK and GC-YN were relatively sensitive to rTNF, and their growth was significantly inhibited by rTNF at 5 x 10(3) U/head, however, the tumors regrew after treatment. Li-7 and BDC-SN were resistant to rTNF. The effects of rTNF in combination with recombinant interferon-gamma (rIFN-gamma), recombinant interleukin-2 (rIL-2), or streptococcal preparation OK-432 were assessed in mice transplanted with GC-YN. All combinations of rTNF at 5 x 10(3) U/head and other BRMs were more effective than rTNF alone, and GC-YN tumors were completely regressed after treatment with a combination of rTNF and rIFN-gamma or rTNF and OK-432. However in all cases, the combination of rTNF at 10(3) U/head and any other BRM did not improve the effect. Furthermore, the adverse effects of the combinations were more serious than those of rTNF alone. TNF may still be a useful cytokine, because it can induce the regression of tumors. However, for its clinical application, a method should be developed to reduce its side effects.

Animals↗
PubMed1991

Comparative study on various combination chemotherapies against human gastric cancer xenograft lines of well- and poorly-differentiated adenocarcinomas transplanted in nude mice.

Two human gastric cancer xenograft lines (GC-YN and GC-SF) transplanted in nude mice were employed to evaluate and compare the anticancer effect of seven single anticancer agents and their various combinations. Mitomycin C, cisplatin (Briplatin) (CDDP) and 5-fluorouracil (5-FU) were screened out to be effective against GC-YN and only epirubicin (Farmorubicin) (EPIR) was effective against GC-SF. Combinations of two of these 'effective' agents revealed that FP (5-FU + CDDP) is the most effective two-agent combination regimen against both lines, and some of those 'ineffective' single agents showed synergistic effects against both lines when combined with 5-FU. Moreover, three-agent combinations composed of FP and one of the other five agents were also evaluated to select out the most effective regimen. All the combinations showed higher inhibition on the tumor growth of GC-YN than FP regimen, and FP + adriamycin (Adriacin) (ADR) and FP + EPIR were more effective against GC-SF than FP. However, taking toxic effects into consideration, the results suggest that CDDP + 5-FU + EPIR (FPEPIR) may be the regimen most worthy of clinical trial in the chemotherapy against human gastric cancer.

Adenocarcinoma↗
PubMed1991

Low uracil concentration in the liver might be responsible for the decreased antineoplastic activity of fluoropyrimidines in mice with CCl4-induced chronic liver dysfunction.

Some fluoropyrimidines are considered to be metabolized in liver microsomes. The present study was designed to assess the effect of chronic liver dysfunction on the antineoplastic activity of fluoropyrimidines. Chronic liver dysfunction was induced in BALB/c mice by 8 weeks of CCl4 injections. The 5-fluorouracil (5-FU)-sensitive MOPC-104E and 5-FU-resistant Meth-A cells were inoculated subcutaneously into the mice and then various fluoropyrimidines were administered intragastrically. The antitumor activity of the fluoropyrimidines decreased in mice with chronic liver dysfunction, although the concentration of 5-FU in the tumor of normal mice did not differ from that of mice with liver dysfunction. However, the concentration of uracil in the liver was decreased in mice with chronic liver dysfunction. On the other hand, the percent conversion of Tegafur [1-(2-tetrahydrofuryl)-5-FU] to 5-FU in the normal liver did not differ from that in the dysfunctional liver. These results suggest that low uracil concentrations in the liver may result from chronic liver dysfunction and lead to decreased antitumor efficacy of fluoropyrimidines.

Animals↗
PubMed1991

The clinical status and histopathological factors affecting natural killer cells of peripheral blood lymphocytes in patients with gastric cancer.

The in vivo function of NK cells is still uncertain, and there are various contradictory reports on NK cells in gastrointestinal cancer. In the present study the activity and proportion of NK cells (Leu 11 + cells) in peripheral blood were assessed in 71 patients with gastric cancer, and analysed with respect to the clinical and histopathological factors, such as the clinical stage, tumor size, degree of invasion, metastasis, histology, etc. There were no differences in the proportions and activities of NK cells between normal volunteers and gastric cancer patients. A low NK cell activity was associated with early gastric cancers (carcinoma in the mucosa or submucosa) less than 2 cm in diameter, large advanced tumors (invasion beyond the muscularis propria) greater than 8 cm in diameter, and metastasis of adjacent regional (perigastric) nodes. Liver metastasis did not affect the NK cell activity, however a high NK activity was found in patients with peritoneal dissemination. The NK activity did not correlate with the proportion of Leu 11 + cells in normal volunteers or in patients with early gastric cancer, however the activity and proportion of NK cells correlated with each other in patients with advanced gastric cancer. These results suggest that the preoperative evaluation of circulating NK cells in gastric cancer patients may be beneficial to assess the extent of nodal metastasis, the degree of tumor invasion, and peritoneal dissemination.

Adult↗