UFT and its metabolite gamma-butyrolactone (GBL) inhibit angiogenesis induced by vascular endothelial growth factor in advanced cervical carcinoma

OBJECTIVE

The aim of this study was to evaluate the potential role of UFT and its metabolite gamma-butyrolactone (GBL) for inhibition of angiogenesis induced by vascular endothelial growth factor (VEGF) in advanced cervical carcinoma by the determination of serum GBL and VEGF, and by immunohistochemical staining to assess VEGF protein expression, before and after UFT therapy.

METHODS

The subjects were 35 patients with an advanced cervical carcinoma and five healthy volunteers between 2002 and 2003 at Hiroshima University Hospital, under informed consent. The patients received two courses of oral fluoropyrimidine (UFT) therapy at a dose of 600 mg/day for 5 and 2 days off treatment. Serum GBL and VEGF was measured before and after UFT therapy by the gas chromatography mass spectrometry and ELISA-kit in 22 patients and five healthy volunteers, respectively. Immunohistochemical detection of VEGF protein was done in 35 cervical cancers. Results The mean serum GBL level before and after UFT therapy was 21.9 +/- 2.3 and 79.3 +/- 6.2 ng/ml, respectively, and it was significantly increased after UFT administration (P < 0.0001). The mean serum VEGF level before and after UFT therapy was 95.3 +/- 28.1 and 67.5 +/- 11.2 pg/ml, respectively, and it was decreased by UFT administration. In 20 out of 33 (66.6%) patients who were detected with VEGF protein, VEGF protein expression was decreased by UFT therapy. The Delta GBL value (GBL after UFT--GBL before UFT therapy) showed a significant inverse correlation with Delta VEGF value (VEGF after therapy--VEGF before therapy) (r2 = 0.940).

CONCLUSIONS

Our findings suggest that UFT and its metabolite GBL inhibit angiogenesis induced by VEGF to have an antitumor effect on cervical cancer.

In vitro cell culture model for anti-cataract drug penetration studies

Immortalized human corneal epithelial cells (HCECs) and human lens epithelial cells (HLECs) were cultured in vitro. Cells were observed under a phase-contrast microscope and the integrity of cell monolayers was assayed by transepithelial electrical resistance (TEER) determination. The permeability of disulfiram (DSF) through a HCECs monolayer was compared with that of DSF through an excised rabbit cornea. The permeability coefficients of DSF through a HCECs monolayer and excised rabbit cornea were 29.5 +/- 4.8 x 10(-6) cm/s and 34.7 +/- 5.2 x 10(-6) cm/s, respectively. Diethyldithiocarbamate (DDC) had high permeability through HLECs monolayer with a permeability coefficient of 44.6 +/- 7.1 x 10(-6) cm/s. The cytotoxicity of DDC against HLECs was investigated using the trypan blue exclusion test. For a DDC concentration of 5 mmol/l, more than 85% cells were viable. DH3a1 mRNA was expressed in cultured HLECs. The expression of aldehyde dehydrogenase 3a1 (ALDH3a1), which may be be responsible for DSF-DDC conversion, was detected using RT-PCR and agarose gels electrophoresis. These results demonstrate that the permeability of DSF can be detected and intra-ocular drug action may be predicted using the cultured HCEC and HLEC monolayers as model.

Stromelysin-1 (MMP-3) is critical for intracranial bleeding after t-PA treatment of stroke in mice

BACKGROUND

Tissue-type plasminogen activator (t-PA) is approved for treatment of ischemic stroke patients, but it may increase the risk of intracranial bleeding (ICB). Matrix metalloproteinases (MMPs), which can be activated through the plasminogen/plasmin system, may contribute to ICB after ischemic stroke.

OBJECTIVES

To explore the contribution of plasminogen, MMP-3 and MMP-9 to ICB associated with t-PA treatment after ischemic stroke.

METHODS

Using a thrombotic middle cerebral artery occlusion (MCA-O) model, ICB was studied in mice with genetic deficiencies of plasminogen (Plg(-/-)), stromelysin-1 (MMP-3(-/-)), or gelatinase B (MMP-9(-/-)) and their corresponding wild-type (WT) littermates. The induction of MMP-3 and MMP-9 was also studied in C57BL/6 WT mice.

RESULTS

ICB induced by t-PA (10 mg kg(-1)) was significantly less than WT in Plg(-/-) (P < 0.05) and MMP-3(-/-) (P < 0.05) but not in MMP-9(-/-) mice. Furthermore, administration of the broad-spectrum MMP inhibitor GM6001 after t-PA treatment reduced ICB significantly (P < 0.05) in MMP-3(+/+) mice, but had no effect on MMP-3(-/-) mice. MMP-3 expression was significantly enhanced at the ischemic hemisphere; with placebo treatment, it was expressed only in neurons, whereas it was up-regulated in endothelial cells with t-PA treatment. Although MMP-9 expression was also significantly enhanced at the ischemic brain, the amount and the distribution were comparable in mice with and without t-PA treatment.

CONCLUSIONS

Our data with gene-deficient mice thus suggest that plasminogen and MMP-3 are relatively more important than MMP-9 for the increased ICB induced by t-PA treatment of ischemic stroke.

Plasminogen activator inhibitor-1 contributes to the deleterious effect of obesity on the outcome of thrombotic ischemic stroke in mice

BACKGROUND

It is widely accepted that obesity is a risk factor for ischemic heart disease, but the association with stroke is less clear. Adipose tissue is an important source of plasminogen activator inhibitor-1 (PAI-1), the main inhibitor of plasminogen activation.

OBJECTIVE

To test the hypothesis that elevated PAI-1 levels associated with obesity negatively affect the outcome of thrombotic ischemic stroke.

METHODS

Middle cerebral artery (MCA) occlusion was induced photochemically in mice with nutritionally induced or genetically determined obesity and their lean counterparts.

RESULTS

The MCA occlusion time (to obtain complete occlusion) was significantly shorter in obese (nutritionally induced) than in lean wild-type (WT) C57Bl/6 mice, whereas the infarct size was significantly larger and intracranial hemorrhage (ICH) was enhanced (all P < 0.05). Similar observations were made in genetically obese ob/ob mice, as compared to lean WT littermates. In both strains, obesity was associated with markedly elevated circulating PAI-1 levels, probably originating from the fat tissue. In contrast, PAI-1-deficient lean and obese mice did not display significant differences in MCA occlusion time, infarct volume or ICH.

CONCLUSIONS

Plasminogen activator inhibitor-1 may play a functional role in the deleterious effect of obesity on the outcome of thrombotic ischemic stroke in mice.

Differential regulation of DEC2 among hypoxia-inducible genes in endometrial carcinomas

In this study, we demonstrate an important role of activation of the hypoxia-inducible factor-1 (HIF-1) pathway in endometrial carcinogenesis and tumor phenotype development of endometrial carcinoma, and suggest a unique role of the HIF-1-target gene, differentiated embryo chondrocyte 2 (DEC2), in carcinogenesis. Hypoxia caused an increase in HIF-1alpha protein expression in 4 endometrial carcinoma cell lines. The expressions of its 5 target genes - DEC1, DEC2, carbonic anhydrase-9 (CA9), vascular endothelial growth factor (VEGF), and solute carrier family 2, member 1 (SLC2A1) - also reactively increased in most of the cell lines, except for DEC2 in the SNG-M cells. The expression levels of DEC2, CA9, and SLC2A1 were significantly higher in the 4 atypical hyperplasia tissues and 82 endometrial carcinomas compared with those in the 21 normal endometria. Clinicopathological analyses of carcinoma patients revealed a significant correlation of the VEGF and SLC2A1 expression with the status of lymph-vascular involvement and lymph node metastasis. The expression levels of CA9 and VEGF were significantly higher in the tumors of post- as opposed to pre-menopausal patients. The SLC2A1 expression was also related to the FIGO stage, but the DEC2 expression was inversely related to the FIGO grade. The activation of the HIF-1 pathway could be related to endometrial carcinogenesis, and the component, DEC2, could have different expression-regulatory mechanisms and unique roles in carcinogenesis.

Prediction of individual response to platinum/paclitaxel combination using novel marker genes in ovarian cancers

We attempted to identify potent marker genes using a new statistical analysis and developed a prediction system for individual response to platinum/paclitaxel combination chemotherapy in ovarian cancer patients based on the hypothesis that expression analysis of a set of the key drug sensitivity genes for platinum and paclitaxel could allow us to predict therapeutic response to the combination. From 10 human ovarian cancer cell lines, genes correlative in the expression levels with cytotoxicities of cisplatin (CDDP) and paclitaxel were chosen. We first selected five reliable prediction markers for the two drugs from 22 genes already known as sensitivity determinants and then identified another 8 novel genes through a two-dimensional mixed normal model using oligomicroarray expression data. Using expression data of genes quantified by real-time reverse transcription-PCR, we fixed the best linear model, which converted the quantified expression data into an IC(50) of each drug. Multiple regression analysis of the selected genes yielded three prediction formulae for in vitro activity of CDDP and paclitaxel. In the same way, using the same genes selected in vitro, we then attempted to develop prediction formulae for progression-free survival to the platinum/paclitaxel combination. We therefore constructed possible formulae using different sets of 13 selected marker genes (5 known and 8 novel genes): Utility confirmation analyses using another nine test samples seemed to show that the formulae using a set of 8 novel marker genes alone could accurately predict progression-free survival (r = 0.683; P = 0.042).

Expression of Tumor-Associated Differentially Expressed Gene-14 (TADG-14/KLK8) and Its Protein hK8 in Uterine Endometria and Endometrial Carcinomas

To clarify the biological behavior of TADG-14/KLK8, we investigated TADG-14/KLK8 mRNA by semiquantitative RT-PCR and hK8 expression by immunohistochemistry using 37 normal endometria and 44 endometrial carcinoma tissues. TADG-14/KLK8 mRNA expression levels were significantly higher in proliferative compared to secretory phase endometria (p = 0.0143). Levels of TADG-14/KLK8 mRNA expression correlated with hK8 protein levels. hK8 was detected in 73.3% (11/15) of endometria with a significantly higher detection rate in the proliferative compared to secretory and atrophic phase endometria (p = 0.0002). High expression of hK8 was found in 61.4% of endometrial carcinomas compared to 35.1% of endometrial tissue samples (p = 0.0187). hK8 expression was significantly higher in stage I (p = 0.0433, 0.0038) and grade 1/2 (G1/2) of the tumors (p = 0.0195, 0.0044). We suggest that expression of TADG-14/KLK8may be regulated by sex steroid hormones in endometria. Our results indicate that elevated TADG-14/KLK8 expression is an early event in endometrial carcinogenesis, and may potentially serve as a useful early biomarker for the detection of endometrial carcinomas in menopausal women.

Villoglandular papillary adenocarcinoma of the uterine cervix responding to neoadjuvant chemotherapy with docetaxel and cisplatin: a case report

Villoglandular papillary adenocarcinoma (VGPA) of the uterine cervix is a rare neoplasm, and its treatment has rarely been reported. We report a patient with VGPA stage IIA responding to neoadjuvant chemotherapy with docetaxel (60 mg/m2 as an intravenous infusion) and cisplatin (70 mg/m2 as an intra-arterial infusion). At 3 weeks after completing one course of this regimen, the tumor size was reduced from 5.3 x 4.0 cm to 2.0 x 2.0 cm (81.1% reduction), revealed by computed tomography. Accordingly, the patient underwent radical hysterectomy, and there have been no signs of recurrence. Thus, the combination of docetaxel and cisplatin is suggested to be useful for neoadjuvant chemotherapy of cervical adenocarcinoma.

Immunohistochemical examination of cytological differentiation in osteosarcomas

In this immunohistochemical examination, the expression of Runx2, Notch1, Delta and Osteopontin peptides were detected in neoplastic cells in 10 Japanese cases of osteosarcoma. Immunohistochemically, Runx2 peptide expression appeared in the cytoplasm of almost all neoplastic cells of the 10 cases examined. However, Notch1 peptide expression appeared in the cytoplasm of neoplastic cells in the localized and comparatively well-differentiated area of osteosarcoma, which osteoblastic and chondroblastic containing osteoid and/or chondroid tissues. No expression of Notch1 peptide was detected in the fibroblastic and poorly differentiated areas. Delta peptide appearance was nearly the same pattern of Notch1 peptide. Expression of Osteopontin peptide appeared in almost all cells and the strength expression was shown in the area of comparatively well-differentiated tissues. Therefore, these results suggest that Runx2, Notch1, and Delta peptides are closely related to cytological differentiation or acquisition of tissue specific characteristics in neoplastic cells in osteosarcomas.

Predicting the chemosensitivity of ovarian and uterine cancers with the collagen gel droplet culture drug-sensitivity test

We investigated the utility of the collagen gel droplet culture drug-sensitivity test (CD-DST) for predicting the response of gynecological cancers to chemotherapy. Eighty-three cancer patients were enrolled in this study: 26 ovarian, 29 cervical and 31 endometrial cancers. The CD-DST was performed at various concentrations of drugs. We calculated the T/C ratio, where T is the total volume of the treated culture and C is the total volume of the control culture, and a T/C ratio of 50% or less was defined as sensitive in vitro. The efficacy rate (%) was defined as the number of cultures with a T/C ratio of 50% or less, divided by the total number of evaluable cultures. True-positive cases were defined as clinical responders (complete+partial responses) and true-negative cases were defined as clinical non-responders. The overall tumor evaluation rate was found to be 79.1%. The appropriate drug concentrations were selected as 1.0 microg/ml for cisplatin, 20.0 microg/ml for carboplatin, 1.0 microg/ml for paclitaxel and 0.1 microg/ml for docetaxel by the linear regression equations. The in vitro sensitivity for each drug showed a significant correlation with clinical response rates (r=0.592, p=0021). We therefore conclude that the CD-DST can be used to predict the response to anti-cancer drugs, and may also provide important information by contributing to the development of new chemotherapy regimens.

Effects of plasminogen activator inhibitor-1 on ischemic brain injury in permanent and thrombotic middle cerebral artery occlusion models in mice

BACKGROUND AND OBJECTIVES

Tissue plasminogen activator (t-PA) improves the outcome of ischemic stroke by recanalization of occluded vessels, but has neurotoxic side effects in experimental stroke models. Here, the effect of plasminogen activator inhibitor-1 (PAI-1), an endogenous inhibitor of t-PA, on ischemic infarct volume was studied.

METHODS

After either permanent ligation or thrombotic occlusion of the middle cerebral artery (MCA), infarct volume, spontaneous reperfusion of thrombosed MCA, t-PA/PAI-1 complex level, and blood-brain barrier (BBB) permeability in the ischemic region was studied in transgenic mice with overexpression of PAI-1 and wild-type littermate controls and in mice with intracerebroventricular injection of human PAI-1.

RESULTS

Infarct volume was smaller in PAI-1 transgenic mice (2.9 +/- 3.7 mm3, mean +/- SD) than in controls (8.9 +/- 5.0 mm3, P < 0.05) after permanent MCA ligation (plasma PAI-1 level 39 +/- 23 ng mL(-1) in transgenic mice vs. 1.5 +/- 0.6 ng mL(-1) in controls), whereas after MCA thrombosis it was larger in transgenics (13.1 +/- 3.1 mm3) than in controls (8.0 +/- 3.2 mm3, P < 0.05). Spontaneous reperfusion of the thrombosed MCA was significantly delayed in transgenic vs. control mice. In the ligation model, t-PA/PAI-1 complex levels were higher and BBB disruption was more pronounced in the ischemic region. Human PAI-1 injection reduced infarct volume by about 50% in wild-type mice but not in t-PA gene deficient mice.

CONCLUSIONS

High PAI-1 levels reduced infarct volume in the permanent MCA ligation model, but enhanced it in the MCA thrombosis model.

Relative expression levels of Th1 and Th2 cytokine mRNA are independent prognostic factors in patients with ovarian cancer

The aim of the present study was to examine mRNA expression levels of Th1 (TNF-alpha , IFN-gamma, and IL-12p40) and Th2 (IL-6 and IL-10) cytokines for any association with clinicopathological characteristics of epithelial ovarian cancer. mRNA was isolated, and cDNA prepared from 40 samples of epithelial ovarian cancers. Expression level of each cytokine mRNA was examined by the real-time PCR technique (GAPDH gene, internal control). Expression ratio (target gene/GAPDH) was used to evaluate gene expression. Results were analyzed against clinical stage, histological grade, and histological type. Prognostic significance of expression levels of each combination of Th1/Th2 values was assessed. Tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) expression levels were significantly higher in serous adenocarcinoma than in non-serous adenocarcinoma (p<0.05), but with no difference between individual cytokine mRNA expression levels and clinical stage or histological grade. Log-rank testing showed that high TNF-alpha mRNA expression (p=0.033) and the diameter of largest residual lesion at initial surgery (p=0.012) significantly correlate with longer survival in advanced stage (II/III/IV) ovarian carcinomas. In examining all combinations of Th1/Th2 expression values, the most significant association was between high IFN-gamma.IL-12p40/IL-6 expression levels and better prognosis in advanced stage (II/III/IV) ovarian carcinomas (p=0.004). In multivariate analysis, high IFN-gamma.IL-12p40/IL-6 expression (p=0.009) and the diameter of residual lesion (p=0.011) remained significantly associated with survival, whereas high TNF-alpha expression lost significance. In conclusion, Th1 and Th2 cytokines might play an important role in regulating the immune reaction in epithelial ovarian cancer cells. IFN-gamma.IL-12p40/IL-6 expression may be a useful prognostic molecular marker for patients with advanced ovarian cancer.

Expression of Notch in a case of osteosarcoma of the maxilla

In this immunohistochemical examination, the expression of Notch1 peptide was detected in neoplastic cells in a case of osteosarcoma of the maxilla of a 31-year-old Indonesian male patient. Notch1 peptide appeared in the cytoplasm of neoplastic cells of comparatively well-differentiated areas of the osteosarcoma, an osteoblastic area containing osteoid and/or immature bone tissues. The results suggest that Notch1 is closely related to cytological differentiation or acquisition of cytological characteristics in neoplastic cells of osteosarcoma.

Expression of human kallikrein 7 (hK7/SCCE) and its inhibitor antileukoprotease (ALP/SLPI) in uterine endocervical glands and in cervical adenocarcinomas

To investigate the potential role of human kallikrein 7 (hK7/SCCE) and its inhibitor antileukoprotease (ALP/SLPI) in the development and progression of uterine cervical adenocarcinoma, we examined hK7 and ALP protein expression by immunohistochemistry in 70 cervical adenocarcinomas and 13 normal cervical tissues. Positive hK7 expression rates in normal endocervical glands and in cervical adenocarcinomas were 46.2 and 80%, respectively. A significantly higher hK7 expression rate was observed in cervical adenocarcinomas compared to normal endocervical glands (p=0.0099). In contrast, positive ALP detection rates in normal endocervical glands and in cervical adenocarcinomas were 100 and 15.7%, respectively. A significantly lower ALP detection rate was observed in cervical adenocarcinomas compared to normal endocervical glands (p<0.0001). There was a significant inverse correlation between hK7 and ALP expression status (p=0.0010). However, no statistically significant differences in hK7 or ALP expression status were found with respect to age, clinical stage, histological grade and lymph node metastasis status in cervical adenocarcinoma cases. Log-rank testing showed that advanced clinical stage and positive lymph node metastasis significantly correlated with poor patient survival (p=0.0005 and p<0.0001, respectively), whereas no correlation was found between hK7 or ALP expression and survival. These results suggest that increased expression of hK7 and decreased expression of ALP might play an important role in cervical adenocarcinoma development.

Clinicopathologic study of 56 patients with endometrial cancer during or after adjuvant tamoxifen use for their breast cancers

OBJECTIVES

The aim of this study was to describe the clinicopathologic features and prognosis of endometrial cancer patients diagnosed during or after tamoxifen treatment for breast cancer.

METHODS

Fifty-six tamoxifen-related endometrial cancers were identified from 10 hospitals in Japan. Past users were defined as endometrial cancer patients diagnosed more than 12 months after the cessation of tamoxifen treatment for breast cancer. All other users were classified as recent users.

RESULTS

Age at diagnosis of the endometrial cancer ranged from 29 to 81 years. Sixteen (29%) and 19 (34%) patients were nulliparous and overweight, respectively. When the patients were divided into two groups: 30 recent and 26 past users, the distribution of various clinical characteristics, except for age at the time of diagnosis for endometrial cancer and the interval between the diagnoses of two cancers, was similar for two groups. The daily dose, duration and cumulative dose also showed no significant difference between the two groups. Past users had histopathologically more invasive tumors showing prognostically more unfavorable subtypes than recent users. The background lesions including endometrial polyps and diffuse cystic changes were similar for the two groups. The cumulative 3-year survival was significantly worse for past users than for recent users (74.8% and 96.4%, respectively, P < 0.04). In multivariate analysis including recentness of tamoxifen use and age at diagnosis of endometrial cancer, the significance of past user disappeared.

CONCLUSIONS

Past users had a worse prognosis of endometrial cancer with more invasive histologic features than recent users, probably because they included more elderly patients.

Comparative effects of microplasmin and tissue-type plasminogen activator (tPA) on cerebral hemorrhage in a middle cerebral artery occlusion model in mice

BACKGROUND

Thrombolytic therapy of ischemic stroke with tissue-type plasminogen activator (tPA) improves clinical outcome which may, however, be partially offset by significant intracerebral bleeding (ICB).

OBJECTS

The comparative effects of microplasmin (microPli) and tPA on ICB were evaluated in a thrombotic middle cerebral artery (MCA) occlusion model in mice.

METHODS

A dose of microPli (5 mg kg(-1)) or tPA (4 mg kg(-1)) which are comparably effective for reduction of brain damage, or a double dose (10 or 8 mg kg(-1), respectively) or the microPli excipient as a control were intravenously administered as a bolus at 30 min or 4 h after MCA occlusion. ICB was measured at 24 h by hemoglobin assay of exsanguinated brain extracts. Bleeding time was measured by tail cutting.

RESULTS

In controls given solvent at 4 h, ICB was on average 8.8 micro L, which was significantly increased with 10 mg kg(-1) microPli and with 4 and 8 mg kg(-1) tPA to 12-13 micro L (P < 0.05 each vs. controls, n = 7-9), whereas 5 mg kg(-1) microPli did not affect bleeding (8.5 micro L P = NS vs. controls, n = 7). When given at 30 min, neither microPli nor tPA altered ICB (6.3-6.8 micro L, mean; n = 7-9). tPA but not microPli increased bleeding time; from 2.4 min in controls to 5.9 min (median, P < 0.05 vs. controls) and 8.7 min (P < 0.01 vs. controls) with 4 and 8 mg kg(-1), respectively, and to 2.3 and 2.9 min with 5 and 10 mg kg(-1) microPli, respectively (n = 10).

CONCLUSIONS

microPli at a dose comparably effective as tPA for brain damage reduction induced significantly less ICB, and less bleeding time prolongation in mice with thrombotic MCA occlusion.

Human papillomavirus DNA status after loop excision for cervical intraepithelial neoplasia grade III - A prospective study

The aims of the study were to investigate the relationship between human papillomavirus (HPV) DNA status and recurrence of cervical intraepithelial neoplasia (CIN) after loop excision (LEEP/LLETZ). Women (n=161) who underwent loop excision for CIN III and who were followed up prospectively for at least 4 years were the study cohort. Cervical smear cytology and testing for HPV DNA was performed at 3, 6 and 12 months prospectively and thereafter at intervals of 6-12 months, using the PCR method with a consensus primer targeting the L1 region. There has been no recurrence in 141 (81.6%) out of 161 subjects, while squamous intra-epithelial lesions (SIL) of low or high grade on cytology and CIN grade I-III on histology have been detected in 20 subjects. Prior to loop excision, HPV DNA was detected in 17 subjects who developed recurrence (9 had type 16, 2 each had types 18 and 52, and 1 each had types 31, 51, 58, and unknown). Within 3 months postoperatively, 12 (70.7%) subjects became negative for HPV, but 2 remained positive for the same type (1 each had types 16, 18), along with high-grade SIL on cytology, and CIN III on histology within 6 months, so repeat loop excision was performed. On the other hand, cytological findings were normalized in all transiently infected subjects within 18-36 months. Our results suggest that loop excision has improved HPV infection in many cases of CIN III and the persistent infection with a high-risk type of HPV is a predictor of the recurrence of CIN grade III.

Expression of osteoclast differentiation factor and osteoclastogenesis inhibitory factor in rat osteoporosis induced by immunosuppressant FK506

Immunosuppressant drugs are currently required by transplant recipients for the remainder of their lives, despite the many adverse effects associated with these therapies. Acute osteoporosis is one such effect, and a reproducible osteoporosis model has been established through the administration of the immunosuppressant drug FK506 in rats. The cause of this osteoporosis has been shown to be abnormal osteoclast proliferation, altering the process of bone remodeling. However, the reasons why FK506 induces osteoclast proliferation and whether this process is mediated by cytokine changes or an increase in bone resorption factors have been unclear. An investigation was therefore conducted focusing on the recent discoveries of osteoclast differentiation factor (ODF) and osteoclastogenesis inhibitory factor (OCIF). These factors led to elucidation of the osteoclast differentiation-maturation mechanism. An osteoporosis model was produced in rats utilizing intramuscular FK506 injection (1 mg/kg) for 28 consecutive days. Trabecular bone resorption was observed inferior to enchondral ossification in the FK506 group, and tartrate resistant acid phosphatase (TRAP) staining revealed a clear increase in osteoclasts at the site of enchondral ossification, relative to the control group. Real-time PCR and in situ hybridization (ISH) demonstrated minimal differences in OCIF expression between control and the treatment groups. However, Real-time PCR revealed clearly increased ODF expression in the treatment group. ODF expression was also shown to be increased in the treatment group using ISH. This was histologically consistent with a region of osteoclast proliferation inferior to enchondral ossification. The results of this study support the hypothesis that FK506-mediated osteoporosis occurs by action of the drug on osteoclasts, promoting expression of ODF messenger ribonucleic acid (mRNA) and thus prompting osteoclast differentiation and maturation.

Telomerase activation in endometrial epithelial cells by paracrine effectors from stromal cells in primary cultured human endometrium

Uterine endometrium displays telomerase activity in a menstrual cycle-dependent manner, despite its somatic origin. This study was performed to elucidate the regulation of telomerase in human endometrium. Telomerase activity and human telomerase reverse transcriptase mRNA expression in proliferative endometrium were significantly stronger than those in secretory endometrium. Their expression was only detected in epithelial cells, although stromal cells also showed proliferation. The growth of epithelial cells decreased day by day in accordance with the decline of telomerase activity. Telomerase activity was significantly stronger in co-cultures of epithelial and stromal cells than in cultures of epithelial cells alone. Moreover, the telomerase activity of co-cultured cells was increased by estradiol or basic fibroblast growth factor, whereas that of epithelial cells cultured alone showed no change. Thus, human endometrium shows reversible telomerase activation during the menstrual cycle, unlike cancer tissues. Also, the telomerase activity of uterine endometrial epithelial cells might be modulated by paracrine effectors released from stromal cells, and not only by the direct action of sex steroids such as estradiol and progesterone.