Leptin, a newly-discovered hormonal product of the obese (ob) gene, is expressed by adipocytes and thought to play a role in the regulation of food intake and metabolism. We tested the hypothesis that leptin signals metabolic information to the reproductive system by examining its effects on the reproductive system of ob/ob mice, which have a congenital deficiency in leptin and are infertile. We treated pair-fed males and females with leptin (50 microg twice daily, ip) or vehicle (n=10/group) for 14 days, after which the animals were bled and killed. Leptin-treated females had significantly elevated serum levels of LH, increased ovarian and uterine weights, and stimulated aspects of ovarian and uterine histology compared to controls. Leptin-treated males had significantly elevated serum levels of FSH, increased testicular and seminal vesicle weights, greater seminal vesicle epithelial cell height, and elevated sperm counts compared to controls. These results demonstrate that leptin stimulates the reproductive endocrine system in both sexes of ob/ob mice and suggest that leptin may serve as a permissive signal to the reproductive system of normal animals.

Baicalein, a widely used Chinese herbal medicine, has historically been used in anti-inflammatory and anti-cancer therapies. However, the anti-metastatic effect and molecular mechanism(s) of baicalein on hepatocellular carcinoma (HCC) remain poorly understood. Therefore, the purpose of this study was to assess the anti-metastatic effects of baicalein and related mechanism(s) on HCC. Based on assays utilized in both HCC cell lines and in an animal model, we found that baicalein inhibited tumor cell metastasis in vivo and in vitro. Furthermore, after treatment with baicalein for 24 hours, there was a decrease in the levels of matrix metalloproteinase-2 (MMP-2), MMP-9 and urokinase-type plasminogen activator (u-PA) expression as well as proteinase activity in hepatocellular carcinoma MHCC97H cells. Meanwhile, the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 were increased in a dose-dependent fashion. Moreover, baicalein treatment dramatically decreased the levels of the phosphorylated forms of MEK1 and ERK1/2. MEK1 overexpression partially blocked the anti-metastatic effects of baicalein. Combined treatment with an ERK inhibitor (U0126) and baicalein resulted in a synergistic reduction in MMP-2, MMP-9 and u-PA expression and an increase in TIMP-1 and TIMP-2 expression; the invasive capabilities of MHCC97H cells were also inhibited. In conclusion, baicalein inhibits tumor cell invasion and metastasis by reducing cell motility and migration via the suppression of the ERK pathway, suggesting that baicalein is a potential therapeutic agent for HCC.

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of cell cycle, the percentage of cells in S phase was significantly decreased, while the percentage of cells in G 1 phase was increased. Flow cytometry assay also showed that ESB had a positive effect on apoptosis. Typical apoptotic morphologies such as condensation and fragmentation of nuclei and blebbing membrane of apoptotic cells could be observed under transmission electron microscope and fluorescence microscope. To further investige the molecular mechanism behind ESB-induced apoptosis, ESB-treated cells rapidly lost their mitochondrial transmembrane potential, released mitochondrial cytochrome C into cytosol, and induced caspase-3 activity in a dose-dependent manner. CONCLUSION: ESB can effectively inhibit the proliferation and induce apoptosis of H22 cells involving loss of mitochondrial transmembrane potential, release of cytochrome C, and activation of caspase-3. INTRODUCTIONScutellaria barbata D.Don (S. barbata) is a perennial herb, also known as Ban-Zhi-Lian (barbat sskullcap) in traditional Chinese medicine. It is mainly distributed in southern China and has been used as an antitumor agent for lung cancer, digestive system cancer, hepatoma, breast cancer, and chorioepithelioma as well as an anti-inflammatory agent and a diuretic in China and Korea [1][2][3][4][5][6][7][8][9] . Extracts from S. barbata (ESB) have in vitro growth inhibitory effects on a number of human cancers including leukemia, colon cancer, hepatoma and skin cancer [4][5][6][7][8][9][10] . However, its antitumor mechanism still remains unclear.It was reported that many Chinese herbs have anticancer properties and induce apoptosis [11] . Three apoptotic pathways have been addressed, including the mitochondrial pathway [12,13] , death receptor pathway [14] , and endoplasmic reticulum stress-mediated apoptosis pathway [15] . The mitochondrial pathway initiates apoptosis in most physiological and pathological situations. Permeabilization outside mitochondrial membrane plays the most important role in mitochondrial apoptosis. In the mitochondria-initiated pathway, mitochondria undergoing permeability transition release apoptogenic proteins such as cytochrome C or apoptosis-inducing factor from the mitochondrial intermembrane space into the cytosol [16] . Released cytochrome C can activate caspase-9, and activated caspase-9 in turn cleaves and activates executioner caspase-3. After caspase-3 activation, some specific substrates for caspase-3 such as poly (ADP-ribose) and polymerase (PARP) are cleaved, and eventually lead to apoptosis [17] . In this study, S. barbata extract showed anti-tumor activity in vitro and could inhibit the growth of mouse H22 hepatoma cells by inhibiting cell apoptosis and cytotoxic effects, demonstrating that the extract from S. barbata can strongly inhibit cell proliferation and induce apoptosis of H22 cells through the mitochondrial dysfunction pathway. MATERIALS AND METHODSReagents and animals N e w b ov i n e s e r u m ( G i b c o, U S A ) , R P M I -1 6 4 0 medium(Gibco, USA), propidium iodide (PI) (Sigma, ...

Programmed death-1 (PD-1) is crucial in cancer and is well characterized as a negative T-cell regulator that functions by delivering inhibitory signals. We aimed to evaluate the relationship between PD-1 polymorphisms (rs10204525, rs2227982, and rs7421861) and breast cancer risk.We selected 560 breast cancer patients and 583 age-, sex-, and ethnicity-matched healthy controls from Northwest China. The PD-1 polymorphisms were genotyped by using Sequenom MassARRAY. Associations were estimated with odds ratios (ORs) and 95% confidence intervals (95% CIs).For the rs10204525 and rs7421861 polymorphisms, no differences in breast cancer risk were found in any of the genetic models. For the rs2227982 polymorphism, the variant genotypes were significantly associated with decreased breast cancer risk (CT vs CC: OR = 0.68, 95% CI = 0.52–0.91; CT + TT vs CC: OR = 0.69, 95% CI = 0.53–0.90). In analyses stratified by age, the decreased risk was observed among the younger subjects (OR = 0.68, 95% CI = 0.47–0.97). We found that the decreased risk observed for the variant genotypes of rs2227982 was associated with the Her-2 status (CT vs CC: OR = 0.55, 95% CI = 0.37–0.84; CT + TT vs CC: OR = 0.56, 95% CI = 0.38–0.82). The haplotype analysis showed that the Ars10204525 Trs2227982 Crs7421861 haplotype was associated with a significantly decreased risk of breast cancer (OR = 0.50, 95% CI = 0.34–0.75).Our findings support an association between the PD-1 rs2227982 polymorphism and decreased breast cancer risk, especially in Her-2 positive breast cancer patients in the Chinese population.

microRNAs (miRNAs) act as a major regulator of acquired chemo-resistance in various types of cancer therapeutics. This study investigated the contribution of miRNAs in influencing multiple drug resistance in esophageal squamous cell carcinoma (ESCC). The sensitivity of four ESCC cell lines (EC109, EC9706, TE-1 and KYSE-150) to 5-fluorouracil (5-FU) and oxaliplatin (OX) was determined by MTT assay. A 5-FU and OX-resistant subline, EC9706R, was established by continuous exposure to stepwise increasing concentration of 5-FU and OX. Microarray technology was used to compare the differential expression of miRNAs between resistant cells and parental cells. Chemo-sensitivity assay was performed to evaluate drug response in EC9706R cells transfected with miRNA mimic or inhibitor. The direct targets of miRNA were identified by employing pathway analysis and then confirmed with luciferase assay. Sixty ESCC tissue samples and their paired adjacent normal tissues were collected to validate the expression of identified miRNA. Mouse models were further utilized to investigate the function of miRNA on acquired chemo-resistance. MicroRNA panel results indicated that a total of 12 miRNAs were differentially expressed and miR-141-3p was highly over expressed in resistant cells. Inhibition of miR-141-3p reversed acquired chemo-resistance in EC9706R cells by stimulating apoptosis. The expression of miR-141-3p was significantly increased in ESCC tissue samples compared to their matched distant normal tissues. In addition, the elevated miR-141-3p expression was found to be associated with ESCC differentiation status and TNM stage. Moreover, Phosphatase and tensin homolog (PTEN) was identified as direct target of miR-141-3p. Western blot exhibited altered protein levels of PTEN, Akt, and PI3k with miR-141-3p inhibitor. An inverse correlation between PTEN expression and miR-141-3p expression was also observed in tissue samples. EC9706R xenograft mouse model became sensitized to 5-FU and OX treatment following miR-141-3p inhibitor transfection in vivo. Our study demonstrated that miR-141-3p contributed to an acquired chemo-resistance through PTEN modulation both in vitro and in vivo.