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H Wakimoto

Publications and source records attributed to H Wakimoto.

At least 55 records · Page 3Linked to original sources
PubMed1995

Cytokine-gene-modified tumor vaccination intensified by a streptococcal preparation OK-432.

Vaccinations with tumor cells engineered to express certain cytokines have been demonstrated to induce potent and specific antitumor immunity. In our previous report, we carried out a comparative study on the ability of cytokine-gene-modified tumor vaccines to induce host immune responses, and found that irradiated tumor cells, genetically modified to secrete granulocyte/macrophage-colony-stimulating factor (GM-CSF tumor vaccine), were the most potent stimulators of systemic antitumor immunity. In this report, using the experimental tumor models in which the GM-CSF tumor vaccine was less effective in immunopotentiation, we found that the combined use of a biological response modifier (BRM) OK-432 remarkably enhanced the antitumor activity induced by the GM-CSF tumor vaccine. These data indicate the possible role of a BRM such as OK-432 to intensify further the specific tumor vaccination therapy.

Animals↗
PubMed1995

Immunohistochemical detection of Ki-67 in replicative smooth muscle cells of rabbit carotid arteries after balloon denudation.

BACKGROUND AND PURPOSE: Ki-67 immunohistochemistry has been shown to be useful for paraffin sections from human species after wet heating. We applied Ki-67 immunohistochemistry to rabbit arteries after balloon denudation and compared the results with proliferating cell nuclear antigen (PCNA) immunohistochemistry. METHODS: Monoclonal antibodies MIB-1 for Ki-67 and PC-10 for PCNA were used to detect replicative smooth muscle cells in rabbit carotid arteries during a period of 4 weeks after balloon endothelial denudation. RESULTS: We demonstrated clear immunoreactivities for Ki-67 in paraffin sections of rabbit arteries after hydrated autoclaving. Ki-67-positive smooth muscle cells appeared throughout the thickened intima 1 week after endothelial denudation. At 2 weeks, Ki-67-positive cells were confined to the surface layer of the intima. PCNA-positive cells appeared in almost the same location by 2 weeks after endothelial denudation but were significantly greater in number than Ki-67-positive cells. PCNA-positive cells remained in the surface layer of the intima 4 weeks after endothelial denudation, while Ki-67-positive cells had almost disappeared from the intima. CONCLUSIONS: Our results indicate that Ki-67 immunohistochemistry using MIB-1 monoclonal antibody provides a powerful tool, even in rabbit species, for the detection of replicative smooth muscle cells during the repair of arterial injury and that it detects replicative cells more accurately than PCNA immunohistochemistry.

Animals↗
PubMed1995

Immunohistochemical detection of progesterone receptors and the correlation with Ki-67 labeling indices in paraffin-embedded sections of meningiomas.

Female sex steroids may play a role in the proliferation of meningiomas. We investigated the progesterone receptor (PgR) immunoreactivities and the Ki-67 labeling indices in the formalin-fixed, paraffin-embedded sections of meningiomas from 39 patients. After autoclave pretreatment of the sections (which were immersed in a citrate buffer), the sections were incubated with the monoclonal antibody for the PgR and the MIB-1 monoclonal antibody for the Ki-67 antigen. In the meningiomas studied, the immunoreactivity for the PgR was moderately to strongly positive in 51%, weakly positive in 21%, and negative in 28%. The nuclear staining for the PgR was clear, and no tumors were positive for the estrogen receptor. The Ki-67 labeling indices of the PgR-positive meningiomas (mean +/- standard deviation, 2.35 +/- 2.12%) were significantly lower than those of the PgR-negative meningiomas (6.53 +/- 4.83%) (P < 0.05). Two meningiomas that had recurred more than once showed high Ki-67 labeling indices and negative immunostaining for the PgR. These findings indicate that the PgR status may be closely related to the growth potentials of the meningiomas. Our results confirm that the immunodetection of the PgR and the Ki-67 antigen on the paraffin sections of meningiomas provides a practical tool for estimating the biological behavior of the meningiomas.

Adult↗
PubMed1994

Adoptive immunotherapy with murine tumor-specific T lymphocytes engineered to secrete interleukin 2.

Adoptive immunogene therapy of cancer is not widely studied, although it has been proposed as a promising strategy for cancer gene therapy. One of the major obstacles to this approach is the difficulty in introducing cytokine genes efficiently into T lymphocytes. In this report, we developed an adoptive immunotherapy model with murine tumor-specific cytotoxic T lymphocytes. By using an adenoviral vector, we achieved up to 100% gene transduction of murine T lymphocytes. Treatment of mice with the cytotoxic T lymphocytes genetically modified to produce interleukin 2 resulted in reduction of tumor metastasis and longer survival from intracerebral tumor death, providing a hopeful strategy for treatments of human cancers.

Adenoviridae↗
PubMed1991

Massive breast enlargement in an infant girl with central nervous system dysfunction.

A 6-month-old female is described who presented with severe idiopathic macromastia. The breast enlargement began at 2 months of age and progressed such that subtotal mastectomies were necessary at 23 months. Extensive hormonal evaluation prior to surgery revealed no evidence of estrogenization or precocious puberty. There was no galactorrhea. A breast biopsy showed immature mammary tissue. In vitro analysis of the patient's serum using a mouse mammary thymidine incorporation assay revealed similar mitogenic activity in the patient's serum compared to adult controls. Post surgical follow up of this patient, 3.5 years later, has revealed no breast enlargement, precocious sexual development, or growth acceleration. Of interest, however, she has manifested an idiopathic degenerative neurologic condition characterized by psychomotor delay, ataxia, and seizures. Remarkably, hormone studies at age 5.5 years showed an exaggerated gonadotrophin response to intravenous gonadotrophin releasing hormone and prepubertal estrogen levels. While this case may represent an extraordinary example of idiopathic premature thelarche, the severe nature of this infant's macromastia in association with neurologic dysfunction and increased gonadotrophins suggests that central nervous system factors were etiologic.

Ataxia↗
PubMed1989

Inhibitory effect of progesterone on cell death of mouse uterine epithelium.

The protective effect of progesterone against cell death of mouse uterine epithelium was evaluated by examining the retention of 5'-[125I]iodo-2'-deoxyuridine [( 125I]IdUrd) incorporated into the whole uterus and the apoptotic index (percentage of apoptotic cells in total cells), which is a good index of physiological cell death. Castrated adult female mice were given a daily injection of oestradiol-17 beta for 3 days, and then an injection of [125I]IdUrd. They were then divided into 4 groups, which received a daily injection of vehicle only, oestradiol-17 beta (E), progesterone (P), or both oestradiol-17 beta and progesterone (EP), and were killed at intervals during these treatments for determination of 125I radioactivity retained in the whole uterus. On treatment with vehicle only, the 125I radioactivity retained in the uterus decreased rapidly, but treatment with E, P or EP reduced the loss of 125I radioactivity significantly. Progesterone did not antagonize the effect of oestradiol-17 beta on the 125I radioactivity retained in the uterus. The apoptotic index of uterine cells was examined by a similar experimental protocol, but without injection of [125I]IdUrd. In the group treated with vehicle only, the apoptotic indices of both luminal and glandular epithelia increased markedly, but the injection of E, P or EP suppressed these increases significantly. Progesterone did not antagonize the effect of oestradiol-17 beta on the apoptotic index. The apoptotic index of stroma was not affected by the injection of E, P or EP. On the other hand, progesterone completely inhibited the increase in the mitotic index of uterine epithelia induced by oestradiol-17 beta. These results show that progesterone alone or in combination with oestrogen reduced cell death in mouse uterine epithelium and that the effects of oestrogen and progesterone on uterine cell death were independent of their actions on cell division.

Animals↗
PubMed1988

Regulation of milk protein synthesis by progesterone in cultured mouse mammary gland.

The effect of progesterone on the synthesis of milk proteins, casein and alpha-lactalbumin was investigated by culturing mammary explants from mid-pregnant mice in serum-free medium. The addition of progesterone at concentrations above 10 ng/ml inhibited both the casein and alpha-lactalbumin accumulation that were induced by the synergistic actions of insulin, prolactin and cortisol. The maximal inhibition was attained at a progesterone concentration of 100 ng/ml. The maximal level of inhibition of the alpha-lactalbumin accumulation was about 90% in the presence of insulin and prolactin or insulin, prolactin and 0.01 microgram/ml of cortisol. The inhibition of the casein accumulation by progesterone was about 80% in the presence of insulin and prolactin, and about 40% in the presence of insulin, prolactin and 1 microgram/ml of cortisol, indicating that cortisol partially antagonized the action of progesterone on the casein synthesis. When the inhibitory effect of progesterone on the accumulation of both alpha-lactalbumin and casein was examined in cultured mammary tissues from virgin, early pregnant, mid-pregnant and late pregnant mice, the degree of inhibition was markedly reduced in tissue from late pregnant mice. This indicates that the susceptibility of mammary gland to the inhibitory action of progesterone varies with the developmental stage of the tissue.

Animals↗
PubMed1988

Increase in collagen production with loss of androgen responsiveness in cultured androgen-responsive Shionogi carcinoma 115 cells.

The collagen production of androgen-responsive and -unresponsive Shionogi carcinoma 115 cells was investigated by culturing them in a medium with or without testosterone. Androgen-unresponsive cells were obtained by culturing a cloned androgen-responsive cell in a testosterone-free medium for 12 weeks. The collagen production of androgen-responsive cells slightly increased in the absence of testosterone, whereas testosterone did not affect the collagen production of androgen-unresponsive cells. Androgen-unresponsive cells produced 3-4 times more collagen than androgen-responsive cells. The major collagen produced by both androgen-responsive and - unresponsive cells migrated to the same position in sodium dodecylsulfate:polyacylamide gel electrophoresis. The present results indicate that the collagen production of androgen-responsive Shionogi carcinoma 115 cells increases with the loss of androgen responsiveness in culture.

Animals↗
PubMed1988

Second pregnancy with spontaneous ovulation following clomiphene- or gonadotropin-induced pregnancy.

For investigation of the rates of spontaneous pregnancy following termination of pregnancy induced by treatment with clomiphene or human menopausal gonadotropin-human chorionic gonadotropin (hMG-hCG) and of spontaneous abortion in the second pregnancy, 119 women (58 with an anovulatory cycle and 141 with amenorrhea) who desired another pregnancy were studied. The rate of spontaneous pregnancy following pregnancy induced by clomiphene was 46.6%, which was significantly (p less than 0.001) higher than that following pregnancy induced by hMG (14.9%). The mean (+/- SEM) period between the termination of the first induced-ovulation pregnancy and the second spontaneous pregnancy was 16.6 +/- 1.4 months. The spontaneous abortion rates in the second pregnancies after pregnancies induced by clomiphene and hMG were 7.5% and 9.8%, respectively, which were significantly (p less than 0.001, p less than 0.05) lower than those in the first pregnancy (25.7%, 33.0%). There was no difference between the spontaneous abortion rates following a first pregnancy which terminated in abortion and those following a pregnancy which ended in birth. These data suggest that a first pregnancy in anovulatory women may restore the ovulatory cycle and have a beneficial effect on the rates of spontaneous abortion in the second pregnancy.

Clomiphene↗
PubMed1988

17-beta-estradiol treatment maintains differentiative potential of virgin mouse mammary gland in culture and its responsiveness to insulin.

Synthesis of the milk proteins, casein and alpha-lactalbumin was not induced in cultured mammary explants from C3H/HeN castrated virgin mice in the presence of lactogenic hormones such as insulin, cortisol and PRL. Replacement therapy with 17-beta-estradiol to the castrated mice completely restored the differentiative potentials of mammary explants, inducing synthesis of the two milk proteins. [3H]thymidine incorporation into DNA synthesized in cultured mammary explants was also decreased by castration to less than 50% (P less than 0.001) of that obtained in intact mice, and 17-beta-estradiol treatment to castrated animals restored DNA synthesis to 90% of the intact level. The addition of insulin to culture medium significantly (P less than 0.001) enhanced [3H]thymidine incorporation into DNA in cultured mammary explants from both intact and 17-beta-estradiol-treated castrated mice but not from castrated animals. Insulin binding sites (1710 +/- 260 sites/cell) to mammary epithelial cells from castrated mice were significantly (P less than 0.05) lower than those from both intact (2870 +/- 300 sites/cell) and 17-beta-estradiol-treated castrated animals (2860 +/- 190 sites/cell). The present findings suggest that 17-beta-estradiol maintains growth and differentiative responses of mammary epithelial cells to insulin, which may be through preserving the number of insulin binding sites in the cells.

Animals↗
PubMed1987

Growth inhibition by progestins in a human endometrial cancer cell line with estrogen-independent progesterone receptors.

The presence of estrogen-independent progesterone receptors (PgR) was demonstrated in a subline of a human endometrial cancer cell line, Ishikawa cells, although the original Ishikawa cells contained estrogen-inducible PgR. Scatchard plot analysis of cytoplasmic binding data in our subline (IK-90) revealed a high affinity binding site for R5020 (Kd, 1.0 nM) with maximum binding sites of 158 fmol/mg protein. Competition experiments showed a binding specificity similar to that of typical PgR. By low-salt sucrose gradient centrifugation, radioactive 8S and 4S peaks were found. The addition of 1 microM progesterone in culture medium resulted in a rapid nuclear translocation of cytoplasmic PgR. In contrast to the original cells, estrogen receptors could not be detected in IK-90 cells, and an addition of 17 beta-estradiol (10 nM) to culture medium failed to increase PgR. Accumulation of glycogen in cytoplasm of IK-90 cells in response to R5020 (0.1-1 microM) was observed by periodic acid-Schiff staining. The addition of R5020 to culture medium (0.1-1 microM) also caused a marked decrease in the growth of IK-90 cells, whereas the other steroids including 17 beta-estradiol, tamoxifen, testosterone, and cortisol had no significant effects. These results demonstrate for the first time the presence of a progestin-responsive human endometrial cancer cell line that contains estrogen-independent functional PgR. IK-90 cells appear to be an ideal model for studying the mechanism of the antiproliferative effect of progestin on endometrial cancer cells.

Cell Division↗
PubMed1987

Roles of antiestrogen binding sites in human endometrial cancer cells.

Estrogen-noncompatible antiestrogen binding sites (AEBS) as well as estrogen receptors (ER), and the growth-inhibitory effect of tamoxifen were investigated in two human endometrial cancer cell lines, IK-90 and HEC-IA cells. IK-90 cells contained specific AEBS, but no ER was found in these cells. Scatchard plot analysis of AEBS in 12,000 g supernatant from IK-90 cells showed a high affinity binding site for tamoxifen (Kd:5.6 +/- 1.0 nM) with the maximum binding site of 457 +/- 47 fmol/mg protein. However, no measurable ER or AEBS was found in HEC-IA cells. The effect of tamoxifen on the growth of cells was found to be identical in both cell lines; the addition of 10 microM tamoxifen to culture medium was cytocidal whereas tamoxifen at lower concentrations (1 nM-1 microM) did not significantly affect the growth of both IK-90 and HEC-IA cells. These results demonstrate for the first time the presence of AEBS in human endometrial cancer cells. The present results also suggest that AEBS does not play a fundamental role in mediating the growth-inhibitory effect of tamoxifen in endometrial cancer cells.

Adenocarcinoma↗
PubMed1987

Effect of clomiphene citrate administration during the early luteal phase on the luteal function and pregnancy rate of women.

To study the effect of clomiphene citrate (clomiphene) administration during the early luteal phase of the menstrual cycle on the luteal function and the pregnancy rate in women, 75 infertile women who ovulated but did not conceive after clomiphene treatment during the early follicular phase and 6 normal cycling women were chosen. Clomiphene was administered orally to 35 of the 75 infertile women at a dose of 50 mg per day for 5 days from the second day of the rise in the basal body temperature (BBT) as well as during the follicular phase, while 40 control patients received clomiphene only during the follicular phase. In the test patients, the rate of pregnancy (25.7%) was significantly (p less than 0.05) higher than that of control patients (10.0%). On the 7th of the rise of BBT, the mean serum progesterone levels of the test patients and normal cycling women treated with clomiphene were significantly (p less than 0.05) higher than those of the control patients. However, the levels of serum estradiol, LH and FSH, the gonadotropin pulsatilities, and the pituitary responses to LH-RH in the test women were not significantly different from those of the control. These data suggest that, when administered during the early luteal phase, clomiphene may act directly on the ovary, enhancing the secretion of progesterone from the corpus luteum, and thereby increasing the rate of pregnancy in infertile women with clomiphene-induced ovulation.

Adult↗
PubMed1986

Retinoic acid enhances cell responses to epidermal growth factor in mouse mammary gland in culture.

Addition of epidermal growth factor (EGF) at up to 100 ng/ml to the medium of cultured explants of mouse mammary gland increased thymidine incorporation into DNA dose dependently. Addition of retinoic acid alone at 10 micrograms/ml to the medium had no significant effect on DNA synthesis, but addition of EGF with retinoic acid enhanced the EGF-stimulated DNA synthesis. Furthermore, pretreatment of mammary explants with retinoic acid enhanced the effect of EGF plus retinoic acid on cell growth. EGF inhibited the synthesis of casein and decreased alpha-lactalbumin activity of mammary explants in culture in the presence of insulin, cortisol, and PRL. Retinoic acid alone had no significant effect on the synthesis of casein, but suppressed alpha-lactalbumin activity dose dependently. Concomitant addition of retinoic acid with EGF had no significant effect on EGF-induced inhibition of casein synthesis, but enhanced EGF-induced inhibition of alpha-lactalbumin activity dose dependently. Measurement of specific binding of [125I]EGF to mouse mammary glands in culture demonstrated that pretreatment of the explants with retinoic acid slightly, but significantly, enhanced the specific binding of EGF to its cellular receptors.

Animals↗