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H Kumazawa

Publications and source records attributed to H Kumazawa.

At least 37 records · Page 2Linked to original sources
PubMed1995

Suppression of natural killer cell activity by serum derived from head and neck cancer patients.

Natural killer (NK) cells play an important role in many immune functions, including the lysis of tumor cells. In this study, we analyzed the influence of serum from 40 patients with head and neck cancer on NK cell activity using a double-layer agar assay. NK cell activity can be express as the inhibitory effect of NK cells on colony growth of K562 cells in the double-layer agar assay. When serum from cancer patients was added in this assay, we observed the reduction of the inhibitory activity of NK cells, not only of autologous NK cells but also of allogeneic NK cells in 24 out of 40 patients. In addition, we compared the TNM staging and survival rate between the reduction group and no-reduction group of NK cell activity. These results suggest that the serum of some patients with head and neck cancer may be an inhibitory factor on NK cell activity and may be involved in host resistance to tumor growth.

Adult↗
PubMed1994

Local injection of OK-432/fibrinogen gel into head and neck carcinomas.

Immunotherapy with biological response modifiers (BRM) is a possible strategy against head and neck solid tumours. However, the rapid disappearance of BRM from the tumour area is one of the reasons for its limited clinical application. In this pilot study, fibrinogen gel containing OK-432 (a compound composed of attenuated Streptococcus pyogenes), an inducer of natural killer cells and T-cell cytotoxity, was injected directly into head and neck solid tumours of 15 patients. A dose of 5 Klinische Einheiten (KE) of OK-432 was reconstituted in 1 ml aprotinin and mixed with fibrinogen, the latter to maintain the OK-432 locally. 3 patients showed tumour regression, and in addition, we observed histological changes in the injected tumour of all patients. These results suggest that OK-432/fibrinogen gel generates a local immune response, leading to tumour regression.

Adult↗
PubMed1993

Influence of LAK cells on expression of HLA-DR antigen on laryngeal carcinoma cell line in new culture systems.

We demonstrated the enhancement of HLA-DR antigen expression on cultured laryngeal carcinoma cells (Hep 2) by in vitro cultivation with LAK cells using flow cytometric and immunohistological analysis. For in vitro cultivation of tumor cells with LAK cells, we used newly developed experimental systems (the Transwell double-dish system and experimental three-dimensional tumors). In flow cytometric analysis, expression of HLA-DR antigen on tumor cells was compared before and after co-cultivation with LAK cells. When tumor cells were cultured separately with LAK cells in a Transwell Petri dish and the expression of HLA-DR antigen on tumor cells was analyzed by flow cytometry, the expression of HLA-DR antigen on tumor cells was increased in a dose-dependent manner related to the number of LAK cells used. Furthermore, when anti-interferon-gamma monoclonal antibody was added to the experimental system, enhancement of HLA-DR antigen expression was blocked. These findings were consistent with immunohistological studies, in which experimental three-dimensional Hep 2 cell tumors were established in double-layered agar with/without being co-cultivated with LAK cells. The expression of HLA-DR antigen in this system was significantly increased when compared to such expression before cultivation with LAK cells. These findings suggested that the culture systems employed in this study could be a possible model for examining solid tumor in vivo biological responses. This enhanced expression of HLA-DR antigen may also represent one of the multi-factorial responses seen with adoptive LAK cell immunotherapy for solid tumors.

Antigens, Surface↗
PubMed1993

Morphologic analysis of three-dimensional tumors developed in fibrin matrix and agar culture system.

The three-dimensional growth of cultured tumor cell lines (HT29, a colon adenocarcinoma cell line; M21, a melanoma cell line; KB, a nasopharyngeal carcinoma cell line) has been investigated in an agar culture system with a fibrin matrix in vitro. The tumor cells developed to tumors 3 x 3 mm in diameter after 10 days in culture in vitro. This size was large enough to allow histologic examination. The tumor cells located in the surface area of the three-dimensional tumor seemed to grow well. However, the tumor cells in the center degenerated or did not proliferate, indicating a lack of nutrition and/or anoxia in the center. The histologic comparison between the xenografted tumors on nude mice and the three-dimensional tumors in vitro suggests that the structures of the three-dimensional tumors were comparable, especially in the surface area, to the xenografted tumors. Furthermore, the antitumor effect of mitomycin C on the three-dimensional tumors was found to be dose-dependent.

Adenocarcinoma↗
PubMed1993

Effects of acetazolamide on acid-base balance in the endolymphatic sac of the guinea pig.

The effects of acetazolamide, a carbonic anhydrase inhibitor, on acid-base parameters in the endolymphatic sac of the guinea pig were investigated using ion-selective microelectrodes. Bicarbonate concentration was reduced and pH shifted to being acidic immediately after administration of acetazolamide. Chloride concentration in the endolymphatic sac increased after carbonic anhydrase inhibition. These findings provide evidence of an active function of carbonic anhydrase in the endolymphatic sac and suggest that carbonic anhydrase activity is involved in the formation of endolymphatic sac fluid.

Acetazolamide↗
PubMed1993

Inhibition of head and neck tumor cell colony growth by lymphokine activated killer cells.

The antiproliferative effect of lymphokine activated killer (LAK) cells on head and neck tumor cells has not previously been elucidated. We studied the inhibitory effects of recombinant interleukin-2 activated lymphocytes on tumor colony formation in semisolid agar, using head and neck tumor cells prepared from established tumor cell lines (K562, HT29, HLaC78) and xenografted head and neck squamous cell carcinomas on nude mice (XKN, XLL, XFL, XKF). LAK cells demonstrated a significant inhibitory effect on colony formation. The effects of LAK cells on cultured tumor cell lines were evaluated in a dose dependent manner using effector: target ratios. In addition, the colony formation of tumor cells derived from xenografted nude mouse was inhibited by LAK cells. These results suggest that LAK cells generate an antiproliferative effect on head and neck tumor cells.

Adenocarcinoma↗
PubMed1993

Establishment of a cisplatin-resistant KB cell line and its characterization.

A KB cell line resistant to cisplatin (KB-rc cell) was successfully established by exposing KB cells to a gradually increasing dose of cisplatin in vitro. The concentration of cisplatin required for 50% inhibition of KB-rc cell proliferation was 1.0 micrograms/ml, while that of KB cells was 0.5 micrograms/ml. Studies of KB-rc cell kinetics after treatment with cisplatin, using flow cytometry, showed that the G2M phase block was inhibited on day 3, and that G0G1 phase cells started to increase on day 5. Therefore, cisplatin-resistance is related to inhibition of the G2M phase block. The decrease of KB-rc cell viability with cisplatin was accelerated by the addition of a Ca antagonist (verapamil) and S phase cells increased on day 3. Verapamil may therefore be useful for enhancement of the effect generated by cisplatin on cisplatin-resistant tumor cells.

Carcinoma, Squamous Cell↗
PubMed1993

Experimental and clinical evaluation of DNA ploidy with use of double staining of keratin/DNA by flow cytometer in head and neck tumor.

As a basic study, an analysis was made, using flow cytometry (FCM), of a mixture of KB cells and lymphocytes after Propidium Iodide (PI)- Fluorescein Isothiocyanate (FITC) double strain. As a result, DNA histogram of only KB cells could be drawn. As a clinical application an analysis was made, using FCM, of tumor of the head and neck after double stain. It enabled the drawing of DNA histogram of only epithelial cells (cancer cells). Changes in DNA histogram of keratin positive cells were classified into three types: Type I: the same diploid type as whole cells, Type II: the same aneuploid type as them, and Type III: the different aneuploid type as them. Among 22 cases of malignant tumor there were 3 cases of Type I, 6 cases of Type II, and 13 cases of Type III. This method could contribute greatly to the detection of cancer cells and DNA diagnosis, and thus be useful clinically.

Biomarkers, Tumor↗
PubMed1993

Chemosensitivity testing of human mouth carcinoma cell line.

The chemosensitivity of KB cells derived from oral epidermal carcinoma to various antitumor agents was analyzed using the MTT[3-(4,5-dimethyl-2-thiazoyl)-2,5-diphenyl-2H tetrazolium bromide] assay. Optical density (OD) for MTT assay was measured with dual wavelengths. The chemosensitivity of the drugs was evaluated by the 50% OD (OD50) of each drug concentration in the control group. Five platinum (Pt) drugs and 3 anthracycline (AC) drugs were used in this study. The chemosensitivity differed among the 5 Pt drugs. No significant difference was observed among the 3 AC drugs. A linear increase in OD corresponding to an increase in number of cells was observed. When 0.1 M sodium succinate (S.S.) was added to 0.4% MTT, the sensitivity increased five-fold compared to the control group without S.S. The MTT assay is a precise, rapid, easy and inexpensive experimental system useful for evaluation of antitumor drug sensitivity on tumor cell lines.

Antibiotics, Antineoplastic↗
PubMed1993

[Antitumor effect of LAK cells on CDDP resistant head and neck carcinoma cell line].

Antitumor effects of lymphokine-activated killer (LAK) cells on cisplatin resistant oral carcinoma cell line were evaluated in vitro by 51Cr release assay and in vivo by nude mouse model. Oral carcinoma cell line (KB) and its subline KBrc resistant to cisplatin were used as target cells. We observed the antitumor effect of LAK cells on both KB and KBrc cells in terms of cytotoxicity of 51Cr release assay, and tumor growth inhibition of nude mouse assay. However, when we compared the antitumor effect between KB and KBrc cells, KBrc cells demonstrated a significant decrease in susceptibility to killing by LAK cells in the in vitro and in vivo model in comparison with the antitumor effect of LAK cells on KB cells. These results, which were not similar to the results of previous studies reported, suggest that alternations of characteristics of tumor cells such as acquired drug resistance result in the decrease in susceptibility of tumor cells against LAK cells.

Animals↗
PubMed1992

Experimental and clinical evaluation by flow cytometry for the mechanism of combination therapy (cisplatin and peplomycin).

Pharmacologic effects of cisplatin (CDDP) and peplomycin (PEP) on tumor cell kinetics were studied both in vitro and in vivo with the aid of flow cytometry (FCM). Double staining with propidium iodide (PI) and fluorescein isothiocyanate (FITC)-labeled bromodeoxyuridine (BrdU) was used to analyze the cell cycle, and the number of viable cells was determined with fluorescein diacetate (FDA). Effects of combining the 2 agents were also studied to establish the most effective method of combination therapy. Furthermore, these agents were tried clinically on the basis of experimental results. Results showed that CDDP exerted its action at the S and G2M phases in the cell cycle and PEP at the G2M phase. Among the combination regimens in the experiments with CDDP, PEP, and CDDP + PEP as analyzed by FCM, the strongest block on the G2M phase was shown in the one at a 2-day interval, resulting in the most effective killing of the tumor cells. Clinical trial of the combination therapy showed the same results as the in vitro experiment; the therapy proved useful for improving the patient's clinical condition and the results obtained with CT imaging and pathology.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

A case of ileus caused by a spiruroid nematode.

A 34-year-old male living in Aichi Prefecture, Japan, complained of lower abdominal pain. Ileus was suspected based on his clinical history and symptoms, and a laparotomy was performed. Four sections of a nematode were found in a large eosinophilic granuloma in the intestinal wall, and were identified as the larva of a spiruroid nematode. This is the third reported case of a spiruroid nematode infection found in the ileum.

Adult↗
PubMed1992

Prediction of doxorubicin resistance in gastrointestinal cancer by P-glycoprotein staining.

Feasibility of immunohistochemical staining of P-glycoprotein for the prediction of doxorubicin resistance in gastrointestinal cancers was examined. Among 10 cancer cell lines which consist of two gastric cancer cell lines and eight colon cancer cell lines, seven cell lines were stained positively by the monoclonal antibody to P-glycoprotein, C219. In consequence of the evaluation on the effect of doxorubicin on these tumour cells by means of succinic dehydrogenase inhibition test (SDI test), zero out of seven cell lines stained positively by C219 was sensitive to doxorubicin, but two out of three cell lines stained negatively were sensitive. Among 23 fresh surgical specimens of gastrointestinal cancers which consisted of 15 gastric cancers and eight colon cancers, seven tumour tissues were stained positively by C219. All P-glycoprotein positive tumours were resistant to doxorubicin. On the other hand, four of 16 P-glycoprotein tumours were sensitive to doxorubicin. These data indicate that positively stained cancer cells by C219 are resistant to doxorubicin.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1992

A kinetic study of egg production, fecal egg output, and the rate of proglottid shedding in Hymenolepis nana.

To estimate the rate of shedding of the proglottids during normal development of Hymenolepis nana in mice, 2 parameters, i.e., egg production and fecal egg output, have been determined. Changes in the number of eggs/proglottid along the length of the worm showed that, not only in vitro but also in vivo, a considerable number of eggs is discharged in situ while the proglottids are still attached to the worm. The in situ egg discharge, however, accounts only for a small fraction of the eggs appearing in the feces, and it can be neglected in the estimation of the shedding of proglottids. In H. nana the larva rotates 90 degrees in the egg during its development. This seems to occur in a short period, quite in concert within each proglottid. The transition point (the proglottid where 50% of the eggs have begun rotating) can be a useful landmark to estimate the rate of proglottid shedding. Egg numbers at the transition points approximate the genuine egg production, because in situ egg discharge mostly occurs only after the proglottids have passed the transition point. The 3 processes, i.e., the rotation of the larva in the egg, the in situ egg discharge, and the shedding of proglottids, usually occur in an orderly way. However, on day 20 of infection, just before the worms are lost (or destrobilated), shedding of proglottids seems to be inhibited, whereas the other processes are apparently normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[Antitumor effect of carboplatin on in vitro three-dimensional tumor].

We studied the antitumor effect of Carboplatin on the three-dimensional tumor in vitro. First, we observed the three-dimensional growth of cultured tumor cell lines (Hep 2, KB and HT 29 cells), which were developed in the combined culture system of fibrin matrix and agar culture. The tumor cells developed a 3 x 3 mm tumor in diameter in the in vitro 10 day-culture system. This size was large enough to allow the histologic study. When we applied Carboplatin to the three-dimensional tumors, histologic change of the three-dimensional tumor developed from Hep 2 and KB cells were observed in a dose dependent manner. However, no remarkable histologic change was observed in the three-dimensional tumor developed from HT 29 cells. These results suggest the experimental system of three-dimensional tumor can predict histologically the antitumor effect of Carboplatin on various tumors at the solid tumor level.

Carboplatin↗
PubMed1991

[Establishing three dimensional tumors in vitro and the reaction of the lymphokine-activated killer cells (LAK) to the three dimensional tumors].

In this study, we attempted to develop a technique, by which three-dimensional tumors were produced from two cultured head and neck tumor cell lines (Hep2, KB) and a colon adenocarcinoma cell line (HT29) using fibrinogen, thrombin, and double layered agar system. The three-dimensional tumor was large enough to perform the histologic study, which showed no significant histologic difference in comparison with the histologic findings of the xenografted tumor on nude mice. Furthermore, we applied this assay model to evaluate the antitumor effect of lymphokine activated killer (LAK) cells on the three-dimensional tumor produced by the technique. When tumor cells were cocultured with LAK cells, the damage of the three-dimensional structure due to the degeneration of tumor cells was observed. These findings suggest that the three-dimensional tumor may be useful to evaluate the antitumor effect of LAK cells in term of head and neck solid tumors.

Adenocarcinoma↗
PubMed1991

Influence of serum derived from patients with head and neck cancer on natural killer cell activity.

The influence of serum from 23 patients with head and neck cancer on natural killer (NK) cell activity was analyzed using a double-layer agar assay, in which NK cells show an activity to inhibit the colony growth of K562 cells. In contrast to normal serum (or no treatment), serum from cancer patients reduced the inhibitory activity of NK cells, not only of autologous NK cells but also of allogeneic NK cells. These results suggest that the serum of patients with head and neck cancer may have some inhibitory factors on NK cell activity and may be involved in host resistance to tumor growth in vivo.

Adult↗