Ruey-Jien Chen

Resveratrol promotes osteogenesis of human mesenchymal stem cells by upregulating RUNX2 gene expression via the SIRT1/FOXO3A axis

Reports of the bone‐protective effects of resveratrol, a naturally occurring phytoestrogen and agonist for the longevity gene SIRT1, have highlighted this compound as a candidate for therapy of osteoporosis. Moreover, SIRT1 antagonism enhances adipogenesis. There has been speculation that resveratrol can promote osteogenesis through SIRT1, but the mechanism remains unclear. In this study we investigated the molecular mechanism of how resveratrol can modulate the lineage commitment of human mesenchymal stem cells to osteogenesis other than adipogenesis. We found that resveratrol promoted spontaneous osteogenesis but prevented adipogenesis in human embryonic stem cell–derived mesenchymal progenitors. Resveratrol upregulated the expression of osteo‐lineage genes RUNX2 and osteocalcin while suppressing adipo‐lineage genes PPARγ2 and LEPTIN in adipogenic medium. Furthermore, we found that the osteogenic effect of resveratrol was mediated mainly through SIRT1/FOXO3A with a smaller contribution from the estrogenic pathway. Resveratrol activated SIRT1 activity and enhanced FOXO3A protein expression, a known target of SIRT1, in an independent manner. As a result, resveratrol increased the amount of the SIRT1‐FOXO3A complex and enhanced FOXO3A‐dependent transcriptional activity. Ectopic overexpression or silencing of SIRT1/FOXO3A expression regulated RUNX2 promoter activity, suggesting an important role for SIRT1‐FOXO3A complex in regulating resveratrol‐induced RUNX2 gene transcription. Further mutational RUNX2 promoter analysis and chromatin immunoprecipitation assay revealed that resveratrol‐induced SIRT1‐FOXO3A complex bound to a distal FOXO response element (−1269/−1263), an action that transactivated RUNX2 promoter activity in vivo. Taken together, our results describe a novel mechanism of resveratrol in promoting osteogenesis of human mesenchymal stem cells by upregulating RUNX2 gene expression via the SIRT1/FOXO3A axis.

Prevalence of Telomerase Activity in Human Cancer

Telomerase activity has been measured in a wide variety of cancerous and non-cancerous tissue types, and the vast majority of clinical studies have shown a direct correlation between it and the presence of cancerous cells. Telomerase plays a key role in cellular immortality and tumorigenesis. Telomerase is activated in 80-90% of human carcinomas, but not in normal somatic cells, therefore, its detection holds promise as a diagnostic marker for cancer. Measurable levels of telomerase have been detected in malignant cells from various samples: tissue from gestational trophoblastic neoplasms; squamous carcinoma cells from oral rinses; lung carcinoma cells from bronchial washings; colorectal carcinoma cells from colonic luminal washings; bladder carcinoma cells from urine or bladder washings; and breast carcinoma or thyroid cancer cells from fine needle aspirations. Such clinical tests for telomerase can be useful as non-invasive and cost-effective methods for early detection and monitoring of cancer. In addition, telomerase activity has been shown to correlate with poor clinical outcome in late-stage diseases such as non-small cell lung cancer, colorectal cancer, and soft tissue sarcomas. In such cases, testing for telomerase activity can be used to identify patients with a poor prognosis and to select those who might benefit from adjuvant treatment. Our review of the latest medical advances in this field reveals that telomerase holds great promise as a biomarker for early cancer detection and monitoring, and has considerable potential as the basis for developing new anticancer therapies.

Immunoaffinity capillary electrophoresis: Determination of binding constant and stoichiometry for antibody-antigen interaction

Affinity capillary electrophoresis (ACE) can provide both qualitative and quantitative information on molecular interactions and affords the advantages of very low sample consumption, high mass sensitivity, short analysis time, and the use of automated instrumentation. It has been applied clinically and biochemically to the determination of the binding constant and to the measurement of the binding stoichiometry for interactions between antibodies (Abs) and antigens (Ags) in free solution. In many situations, the Ag molecule has two or multiple binding sites, each of which has a similar or different intrinsic affinity for binding independently to the combining site(s) on an Ab molecule. The multivalent binding reactions between Ab and Ag molecules often occur. The objective of this review is to describe the uses of ACE in the determination of binding constants and stoichiometry of Ab‐Ag interactions (immunoaffnity capillary electrophoresis), focusing especially on multivalent Ab‐Ag interaction modes. Five model binding systems developed recently using ACE techniques are described with principles and examples: (i) divalent mAb‐monovalent Ag interaction, (ii) divalent mAb‐(homo)polyvalent Ag interaction, (iii) cooperativity of two binding sites of mAb‐monovalent Ag interaction, (iv) monovalent Fab‐divalent Ag interaction, and (v) polyclonal Ab‐monovalent Ag interaction. Finally, the determination of binding stoichiometry of Ab‐Ag interactions by ACE is described.

Prognosis and Treatment of Squamous Cell Carcinoma from a Mature Cystic Teratoma of the Ovary

BACKGROUND/PURPOSE Squamous cell carcinoma (SCC) arising from a mature cystic teratoma of the ovary is rare and only reported sporadically. Clinical information on the disease is limited. This study assesses the clinical characteristics, treatment, outcome and prognostic factors of reported cases. METHODS Two hundred and twenty cases from 1976 through to 2005 in MEDLINE were analyzed for patient age, clinical and laboratory data, extent of disease, tumor markers, treatment and survival rates. Only the 188 cases with surgical staging were included in the survival analysis. RESULTS The disease occurred most often in elderly women (mean, 55.0 +/- 14.4 years) and cysts were large (mean, 13.7 +/- 5.7 cm). Abdominal pain (71.6%) was the most common symptom. Preoperative serum SCC antigen level had a high positive rate (81.3%). Overall 5-year survival rate for all stages was 48.4%. For Stage I, the 5-year survival rate was 75.7%; stage II, 33.8%; stage III, 20.6%; and stage IV, 0% (p < 0.0001). Univariate analysis revealed that tumor stage, patient age, tumor size, preoperative SCC antigen and CA125 levels, and optimal debulking were significant prognostic factors. Further investigation into treatments for all stages revealed that postoperative adjuvant chemotherapy may produce a better survival rate for both stage III and stage IV cases. However, postoperative radiotherapy did not show a similar effect. Multivariate analysis indicated that stage and optimal debulking were significant factors that influenced survival. CONCLUSION A mature cystic teratoma should be treated as early as possible. Tumor stage and optimal debulking are critical to survival. Unlike SCCs of the uterine cervix, postoperative adjuvant chemotherapy may produce a better result than adjuvant radiotherapy for advanced-stage cases.

Clinical significance of tumor-infiltrating lymphocytes in neoplastic progression and lymph node metastasis of human breast cancer.

To investigate the clinical significance of tumor-infiltrating lymphocytes (TILs) within the tumor milieu, we quantitatively measured and compared the subpopulations of TILs in 24 patients with stage I-III breast carcinoma. Peripheral blood mononuclear cells (PBMCs), normal breast parenchyma-infiltrating lymphocytes (NILs), and TILs were isolated from tissue specimens and quantified by flow cytometry. The results showed that increased proportion of CD8(+) T cells, with decreased proportion of CD4(+) T cells, was significant in gated CD3(+) TILs as compared to autologous NILs or PBMCs (P<0.001). The tumor-infiltrating CD8(+) T cells significantly increased with stage progression, reflected in a more strongly decreased CD4/CD8 percentage (P=0.003). The CD4/CD8 percentage of TILs was strongly correlated with lymphovascular permeation and subsequent lymph node metastasis (P<0.001). Increased percentages of tumor-infiltrating CD8(+) T cells with decreased CD4/CD8 percentages are of prognostic importance for cancer progression in human breast cancer.

Malignant ovarian germ cell tumors

Objectives: Fifty patients with malignant ovarian germ cell tumors, which accounts for 10.8% of all ovarian malignancies, were treated from 1977 through 1994. Their cases are reviewed. Methods: The histology includes endodermal sinus tumor (EST) in 15 patients, immature teratoma in 14, dysgerminoma in 13, and mixed germ cell tumor in eight. The mean age at presentation was 21.5 years and mean primary tumor diameter was 16 cm. All patients underwent surgery as the initial treatment, and 10 received more than one operation. Postoperative adjuvant chemotherapy was not given to cases with stage Ia immature teratoma and dysgerminoma. VAC (vincristine, actinomycin D, cyclophosphamide) and BVP (bleomycin, vinblastine, cisplatin) regimens were utilized in early 1980s for EST and advanced‐stage tumors of immature teratoma and dysgerminoma. BEP (bleomycin, etoposide, cisplatin) and EP (etoposide, cisplatin) regimens were applied in advanced‐stage disease and some stage I disease since 1990. VIP (VP‐16, ifosfamide, cisplatin) regimen was employed as salvage regimen in cases where other combinations failed. Results: α‐Fetoprotein (AFP) was elevated in every tumor containing endodermal sinus element, and AFP served as a good indicator for prediction of tumor recurrence. The follow‐up time ranged from 5 to 144 months with the mean of 54.5 months. Conclusions: The survival rate for EST was 54%, that for immature teratoma and dysgerminoma was 85% and 90%, respectively.

Effect of conjugated equine estrogen in combination with two different progestogens on the risk factors of coronary heart disease in postmenopausal Chinese women in Taiwan: a randomized one‐year study

Background.  To compare the effect of hormone replacement therapy (HRT) using estrogen plus dydrogesterone or estrogen plus medroxyprogesterone acetate (MPA) on the risk factors for coronary heart disease (CHD) in postmenopausal women.

Differential clinical characteristics, treatment response and prognosis of locally advanced adenocarcinoma/adenosquamous carcinoma and squamous cell carcinoma of cervix treated with definitive radiotherapy

To compare tumor characteristics and clinical outcome of patients with cervical locally advanced adenocarcinoma (AC)/adenosquamous carcinoma (ASC) and squamous cell carcinoma (SCC).

Comparison of detection of human papillomavirus 16 DNA in cervical carcinoma tissues by Southern blot hybridisation and nested polymerase chain reaction

An association between human papillomavirus (HPV) and cervical neoplasia has been widely reported and HPV DNA is commonly detected in cervical carcinoma tissues. However, estimates of the prevalence of HPV infection differs among various detection methods. Seventy cases of cervical carcinoma were screened for HPV 16 infection by Southern blot hybridisation (SBH) and nested polymerase chain reaction (PCR). According to SBH, the prevalences of HPV 16 DNA in stage I (n = 40) and stage II (n = 30) cervical carcinomas were 52.5 and 63.3%, respectively, and the overall prevalence was 57.1% (40 of 70). By nested PCR, the prevalences of HPV 16 infection in stage I and II cervical carcinomas were 87.5 and 93.3%, respectively, and the overall prevalence was 90.3%. The prevalence of HPV DNA detected by nested PCR was significantly greater than that detected by SBH. The combined concordance of positive and negative results between SBH and nested PCR was 61.4%. The discrepancy resulted mainly from 25 cases (35.7%) that were positive by PCR but negative by SBH. A small copy number of HPV DNA in the these 25 cases was documented by a semi-quantitative PCR method. The nested PCR was more sensitive than SBH and detected cases with low amounts of HPV DNA. The detection of HPV infection varied between these two prevailing detection methods and this should be kept in mind in assessing various epidemiological data concerning HPV infection.

MUC20 overexpression predicts poor prognosis and enhances EGF-induced malignant phenotypes via activation of the EGFR-STAT3 pathway in endometrial cancer.

OBJECTIVE Mucins play a critical role in the malignancy of various tumors and have been identified as diagnostic markers and as attractive therapeutic targets. However, the role of mucin (MUC) 20 in endometrial cancer (EC) is still unknown. METHODS The relationship between MUC20 expression and clinical characteristics of EC was analyzed in 97 EC tumors and 16 normal tissues by immunohistochemistry. Effects of MUC20 on EC cells, HEC-1A and RL95-2, were examined by in vitro cell growth, migration, and invasion assays, as well as in vivo tumor growth in SCID mouse model. Western blotting was performed to analyze signaling pathways modulated by MUC20. RESULTS MUC20 expression was significantly higher in EC tumors compared with the normal tissue. High levels of MUC20 expression in EC tumors were correlated with an unfavorable histologic subtype. Furthermore, MUC20 was an independent prognostic factor for poor survival as evaluated by multivariate analyses. Overexpression of MUC20 in EC cells significantly enhanced cell growth, migration, and invasion, as well as tumor growth in vivo. The MUC20-enhanced invasive behavior was significantly blocked by erlotinib, an EGFR inhibitor. Moreover, MUC20 overexpression enhanced EGF-mediated migration and invasion, suggesting a critical role of EGFR in MUC20-mediated effects. We found that MUC20 overexpression could enhance EGF-induced phosphorylation of EGFR and STAT3. Inhibition of the STAT3 activity by its inhibitor Stattic significantly suppressed the MUC20-enhanced invasive behavior. CONCLUSIONS MUC20 is novel prognostic factor for EC and its overexpression enhances EGF-triggered invasive behavior through activation of EGFR-STAT3 pathway.