Shigeo Morishita

Progestins and danazol effect on cell-to-cell adhesion, and E-cadherin and α- and β-catenin mRNA expressions

Abstract The first step of invasion and metastasis is the detachment of cancer cells in the primary tumor, which is mainly controlled by the function in the adherens junction, consisting of E-cadherin associated proteins (E-cadherin, α- and β-catenins, vinculin, α-actinin, and actin). The cell-to-cell aggregation activity and the expressions of E-cadherin, and α- and β-catenin mRNAs in Ishikawa cells of well-differentiated endometrial cancer were significantly suppressed by estrogen. These suppressions were reversed by progesterone, medroxyprogesterone acetate (MPA) and danazol. Proteins in the adherens junction appeared to be expressed intact and to be functional in Ishikawa cells. Persistent estrogen predominant milieu might contribute to the detachment of well-differentiated endometrial cancer cells, leading to spreading of those cells, while progestins and danazol protect estrogen-induced spreading of those cells.

Enhancing effects of estrogens on endometrial carcinogenesis initiated by N-methyl-N-nitrosourea in ICR mice

The present study was undertaken to examine the effects of estrogens, such as estrone (E1), 17β‐estradiol (E2) and estriol (E3), on endometrial Carcinogenesis initiated by N‐methyl‐N‐nitrosourea (MNU) in mice. A total of 120 female ICR mice received MNU solution (1 mg/100 g body wt.) and normal saline at 10 weeks of age into their left and right uterine corpora, respectively. One week later, they were divided into four groups and treated as follows: Group 1 (30 mice) was given 25 ppm E1‐containing diet; Group 2 (30 mice) was fed 5 ppm E2‐containing diet; Group 3 (30 mice) was given 25 ppm E3‐containing diet; and Group 4 (30 mice) was fed the basal diet alone. At the termination of the experiment (Week 30), all surviving animals were autopsied and histopathological examinations revealed that endometrial adenocarcinomas had developed in all groups. The incidence of adenocarcinomas in the MNU‐treated uterine corpus in Group 1 (25 ppm E1‐feeding, 9/23, 39%) was significantly higher than that in Group 4 (basal diet, 3/26, 12%, P<0.05). Also, the incidences of adenocarcinomas in the MNU‐treated uterine corpus in Groups 2 (5 ppm E2‐feeding, 8/24, 33%) and 3 (25 ppm E3‐feeding, 7/26, 28%) were higher than in Group 4, but the difference was not statistically significant. Feeding of diet containing E1, E2 and E3 increased the incidences of the preneoplastic endometrial lesions (atypical, adenomatous or cystic glandular hyperplasia). In the uterine cervix, small numbers of squmous cell carcinomas, dysplasias or hyperplasias were occasionally found in all groups. These results indicate enhancing effects of the above three types of estrogens on the endometrial carcinogenesis induced by MNU in ICR mice.

Estrogen activates migration potential of endometrial cancer cells through basement membrane

The migration potential through a basement membrane in an endometrial cancer cell line, such as Ishikawa, HEC-1-A or HHUA cell, in terms of strength, was enhanced by estradiol, but not modified by progesterone, medroxyprogesterone acetate (MPA), danazol or tamoxifen alone, by which estradiol-enhanced migration potential was inhibited. The order of the level of estrogen receptor was Ishikawa > HEC-1-A > HHUA cells. Therefore, it is suggested that the invasiveness of endometrial cancer cells might be activated by estradiol via estrogen receptors, but inactivated by progesterone, MPA, danazol or tamoxifen as an antiestrogen action, and that endometrial cancer cells could become invasive in the estrogen-predominant milieu, and the antiestrogenic agents could protect it.

Successful pregnancy in a patient with endometrial carcinoma treated with medroxyprogesterone acetate

A 32-year infertile Japanese woman suffered from endometrial cancer, which was treated with repeated endometrial curettage and medroxyprogesterone acetate for 6 months. The patient then became pregnant and was delivered of a live-born male infant at 37 weeks gestation by cesarean section for placenta previa. At cesarean section there were no abnormal findings in the uterine cavity or other pelvic organs.

Effects of tamoxifen on endometrial carcinogenesis in mice

Two experiments were conducted to determine the effect of tamoxifen (TAM) in mouse endometrium in comparison with that of 17β‐estradiol (E2). In a medium‐term assay, TAM as well as E2 treatment semi‐dose‐dependently increased the levels of fos/jun mRNA and their oncoproteins (Fos/Jun). The long‐term effect of TAM on mouse endometrial carcinogenesis was also examined in the following model. A total of 150 female ICR mice, 12–13 weeks of age, were used. Of these, 125 mice received an injection of N‐methyl‐N‐nitrosourea (MNU) solution (1 mg/100 g body weight) into their left uterine tube and saline into the right. One week later, they were divided into four groups: groups 1 (35 mice) and 2 (30 mice) were given 25 ppm and 5 ppm E2‐containing diet, respectively, while group 3 (30 mice) was fed 5 ppm TAM‐containing diet. Group 5 (30 mice) was fed basal diet alone. The remaining 25 mice (group 4) received 5 ppm TAM‐containing diet alone. At the termination of the experiment (30 weeks), endometrial carcinomas were confirmed to be present in the groups exposed to MNU. TAM increased the incidence of preneoplastic lesions of the endometrium, while E2 enhanced the occurrence of the carcinoma. No carcinomas were found in the group given TAM alone. In the ovaries, corpora lutea were lacking in most of the mice exposed to TAM, suggesting that the animals were not cycling. Such findings indicate that TAM has an enhancing effect on endometrial carcinogenesis in mice, probably via a mechanism involving overexpression of Fos/Jun proteins.

Estrogen induces expression of c-fos and c-jun via activation of protein kinase C in an endometrial cancer cell line and fibroblasts derived from human uterine endometrium

Endometrial fibroblasts derived from uterine endometrium as controls and endometrial cancer cell lines (Ishikawa and HHUA cells) were analyzed for the induction manner of c-fos and c-jun transcripts in endometrial cancers, some of which are estrogen-dependent in growth. Estrogen increased c-fos expression and protein kinase C (PKC) activity in fibroblasts and Ishikawa cells, but not in HHUA cells. Progesterone diminished c-fos and c-jun expression and PKC activity induced by estradiol in the fibroblasts, but not in Ishikawa cells, which persistently overexpressed c-fos and c-jun. In these cells, 12-0-tetra-decanoylphorbol-13-acetate (TPA) increased c-fos and c-jun expression as did estradiol. Pretreatment with 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7) abolished estrogen-inducible over-expression of c-fos and c-jun. The combination of both estradiol and TPA at maximum effective concentration exerted no additive and synergistic effect on induction of c-fos and c-jun expression. In conclusion, persistent activation of PKC might lead to overexpression of c-fos and c-jun in some endometrial cancers with an estrogen predominant milieu, which might be, at least in part, associated with the transformation or growth potential.

Acute myelogenous leukemia in pregnancy: Fetal blood sampling and early effects of chemotherapy

This report documents the acute toxicity of anti‐leukemic chemotherapy on the fetus in utero by umbilical blood sampling. A patient with acute myelocytic leukemia diagnosed at the 23rd week of gestation received combination chemotherapy, and carried the pregnancy to successful delivery at the 34th week. During the course of pregnancy, the fetal condition was evaluated by serial real time sonograms and umbilical blood sampling through cordocentesis. Fetal hemotopoiesis was preserved against maternal chemotherapeutic agents, and no developmental abnormalities were observed. This is the first attempt to evaluate the acute effects of chemotherapeutic agents on the fetus in utero by real time umbilical cord sampling.

Preventive Effects of Glycyrrhizae radix Extract on Estrogen-related Endometrial Carcinogenesis in Mice

Short‐ and long‐term experiments were conducted to examine the effects of Glycyrrhizae radix (Gl radix) extract on mouse endometrial carcinogenesis. Gl radix treatment (2 weeks) decreased the levels of c‐fos/jun mRNA and the corresponding oncoproteins induced by estradiol‐17β(E2) in castrated mice uteri, as determined by reverse transcription‐polymerase chain reaction and Southern blot analysis, and immunohistochemical methods, respectively. For the long‐term assays, 98 female ICR mice were given N‐methyl‐N‐nitrosourea (MNU) solution (1 mg/100 g body wt.) and normal saline (as controls) into their left and right uterine corpora, respectively. They were divided into four groups as follows: group 1 was given 0.625%Gl radix‐ and 5 ppm E2–containing diet; group 2, 5 ppm E2–containing diet; group 3, 0.625%Gl radix‐containing diet; and group 4, the basal diet alone. Gl radix treatment significantly decreased uterine weights and the incidences of uterine endometrial atypical hyperplastic and malignant lesions. It is suggested that Gl radix has inhibitory effects on E2‐related endometrial carcinogenesis in mice, through suppression of estrogen‐induced c‐fos/jun‐expressions.

Inhibitory effects of medroxyprogesterone acetate on mouse endometrial carcinogenesis

The present study was undertaken to examine the effects of cyclic administration of low‐dose progestogen on endometrial carcinogenesis in mice. A total of 115 female ICR mice, 10 weeks of age, were divided into four experimental and control groups. Mice in groups 1–3 received laparotomy and were injected with N‐methyl‐N‐nitrosourea (MNU) solution at a dose of 1 mg/100 g body weight to the left uterine tube and with normal saline to the right uterine tube. From one week after the MNU exposure, groups 1 and 2 were given 5 ppm 17β‐estradiol (E2)‐containing diet throughout the experiment. Mice in group 1 received 5 s.c. injections of medroxyprogesterone acetate (MPA) (2 mg/ mouse) at intervals of 4 weeks from week 7. Group 3 was treated with MNU/normal saline alone. Group 4 consisted of mice treated with MPA alone. At the termination of the experiment (week 30), all animals were killed and autopsied for pathological examinations. It was found that adenocarcinomas and preneoplastic lesions developed in the bilateral uterine corpora in mice of groups 1–3. MPA treatment significantly decreased the weight of the uterine corpus (P< 0.05) and the incidences of endometrial adenocarcinoma and atypical or adenomatous (P< 0.001) but not cystic glandular hyperplasias in the MNU/E2‐treated groups. Additionally, MPA treatment tended to decrease the proliferating cell nuclear antigen‐labeling index in endometrial glandular cells. These data indicate that MPA, even at low dose, has an inhibitory effect on mouse endometrial carcinogenesis induced by MNU and E2.

Preventive effects of danazol on endometrial carcinogenesis in mice

Short and long-term experiments were designed to determine effects of danazol on estrogen-related endometrial carcinogenesis in mice. The short-term assays showed that danazol decreased expression levels of c-fos/jun mRNA and their oncoproteins induced by estradiol-17beta (E2). For the long-term assay, 85 female ICR mice were given N-methyl-N-nitrsourea solution into their uterine corpora. The animals were divided into three groups as follows: Group 1, E2-diet (5 ppm) plus danazol (2 mg/body (s.c.), every 4 weeks); Group 2, E2-diet alone, Group 3, basal diet alone. At 30 weeks, incidences of atypical and complex endometrial hyperplasia were significantly decreased by danazol-treatment. These results suggest that danazol has preventive effects on estrogen-related endometrial carcinogenesis in mice, through the suppression of estrogen-induced c-fos/jun-expression.