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Activation of the transcription factor, signal transducers and activators of transcription 3 (STAT3), has been linked to the proliferation and migration of a variety of human cancer cells. These actions occur via the upregulation or downregulation of cell survival and tumor suppressor genes, respectively. Importantly, agents that can suppress STAT3 activation have the potential for use in the prevention and treatment of various cancers. In this study, an Asiatic acid (AA) derivative, N-(2α,3β,23-acetoxyurs-12-en-28-oyl)-l-proline methyl ester (AA-PMe), is reported to dose dependently suppress constitutive STAT3 activation in gastric cancer cells. This inhibition was mediated by blockade of Janus-activated kinase 2. Additionally, AA-PMe regulated the expression of STAT3-modulated gene products, including cyclin D1, Bax, Bcl-2, c-Myc, and matrix metalloproteinase (MMP)-2 and MMP-9. Finally, transfection with both a STAT3 mimic and an inhibitor reversed the AA-PMe-driven modulation of STAT3 downstream gene products. Overall, these results suggest that AA-PMe is a novel blocker of STAT3 activation and has the potential for the prevention and treatment of gastric cancer. [ABSTRACT FROM AUTHOR]

Asiatic acid (AA; 2α,3β,23-trihydroxyurs-12-ene-28-oic acid) is widely used for medicinal purposes in many Asian countries due to its various bioactivities. A series of AA derivatives has been synthesized in attempts to improve its therapeutic potencies. Herein we investigated the anti-tumor activities of N-(2α,3β,23-acetoxyurs-12-en-28-oyl)-l-proline methyl ester (AA-PMe), a novel AA derivative. AA-PMe exhibited a stronger anti-cancer activity than its parent compound AA. AA-PMe inhibited the proliferation of SGC7901 and HGC27 human gastric cancer cells in a dose-dependent manner but had no significant toxicity in human gastric mucosa epithelial cells (GES-1). AA-PMe induced cell cycle arrest in G0/G1 phase and blocked G1-S transition, which correlated well with marked decreases in levels of cyclin D1, cyclin-dependent kinase CKD4, and phosphorylated retinoblastoma protein, and increase in cyclin-dependent kinase inhibitor P15. Further, AA-PMe induced apoptosis of human gastric cancer cells by affecting Bcl-2, Bax, c-Myc, and caspase-3. Moreover, AA-PMe suppressed the migration and invasion of human gastric cancer cells (SGC7901 and HGC27) cells by downregulating the expression of MMP-2 and MMP-9. Overall, this study investigated the potential anti-cancer activities of AA-PMe including inducing apoptosis and suppressing proliferation, migration and invasion of gastric cancer cells, as well as the underlying mechanisms, suggesting that AA-PMe is a promising anti-cancer drug candidate in gastric cancer therapy. [ABSTRACT FROM AUTHOR]

Objective: Kawasaki disease (KD) can lead to permanent damage to coronary structures, the pathogenesis of which remains unknown. This experiment was designed to investigate whether miR‐223‐3p secreted in the serum of KD patients affects the proliferation and apoptosis of HCAECs in KD by regulating FOXP3. Methods: Blood samples were collected in acute febrile phase of KD, after IVIG treatment, and from healthy controls. Transfected into HCAECs cells by synthetic FOXP3 siRNA/NC. A co‐culture system was established between HCAECs cells transfected with FOXP3 siRNA/NC and THP1 cells added with three sera. Results: Compared with the control group, the expressions of miR‐223‐3p, RORγt, and Th17 in serum of KD patients were significantly upregulated, and the expressions of TGF‐β1, FOXP3 and Treg were significantly downregulated. At the same time, the levels of IL‐6, IL‐17, and IL‐23 were significantly increased, and the levels of IL‐10 and FOXP3 were significantly decreased. After IVIG treatment, the patient's above results were reversed. The serum of KD patients increased the expression of miR‐223‐3p and inhibited the expression of FOXP3 in HCAECs cells. IVIG serum is the opposite. Overexpression of miR‐223‐3p also promoted the apoptosis of HCAECs. In addition, serum from KD patients promoted apoptosis, whereas serum after IVIG treatment inhibited apoptosis. KD patient serum downregulated the expression of FOXP3, Bcl2, TGF‐β1 and IL‐10 in cells, and upregulated the expression of caspase3, Bax, IL‐17, IL‐6, and IL‐23. The opposite results were obtained with IVIG‐treated sera. Conclusion: miR‐223‐3p secreted in serum of KD patients can regulate the expression of FOXP3 and affect the proliferation, apoptosis, and inflammation of cells. [ABSTRACT FROM AUTHOR]

Dihydromyricetin (DHM), a Rattan tea extract, has recently been shown to have anti-cancer activity in mammalian cells. In this study, we investigated the effect of DHM on human melanoma cells. Apart from induction of apoptosis, we demonstrated that DHM induced an autophagic response. Moreover, pharmacological inhibition or genetic blockade of autophagy enhanced DHM-induced cell death and apoptosis, indicating the cytoprotective role of autophagy in DHM-treated human melanoma cells. Further study suggested that the nuclear factor kappa B (NF-κB) signalling pathway was involved in DHM-induced autophagy. Moreover, N-acetyl-cysteine (NAC), an ROS scavenger, abrogated the effects of DHM on NF-κB-dependent autophagy. Taken together, this evidence demonstrates that a strategy of blocking ROS-NF-κB-dependent autophagy to enhance the activity of DHM warrants further attention for the treatment of human melanoma. [ABSTRACT FROM PUBLISHER]

Background Exposure to metals, including essential and nonessential elements, is widespread and may be associated with male reproductive health. Objective To examine whether environmental exposure to metals contributes to reproductive hormone changes, spermatozoa apoptosis and sperm DNA damage in a Chinese population. Methods Eighteen metals (aluminum, arsenic, antimony, chromium, cobalt, copper, cadmium, iron, lead, manganese, molybdenum, nickel, selenium, tin, tungsten, thallium, uranium and zinc) were analyzed in two urine samples collected a few hours apart from male partners of couples attending an infertility clinic. Multivariable linear regression models were used to assess the cross-sectional associations of average urinary metal levels with serum hormones ( n = 511), spermatozoa apoptosis measures ( n = 460) and sperm DNA damage parameters ( n = 516). Results We found significant inverse dose-dependent trends of urinary tin quartiles with total testosterone (T), and tin, nickel, zinc and molybdenum with the ratio of total T to luteinizing hormone (total T/LH ratio) (all P trend < 0.05). Additionally, we found significantly dose-dependent trends of increasing urinary manganese quartiles with increasing percentage of Annexin V +/PI − spermatozoa and increasing iron with decreasing percentage of PI + spermatozoa (both P trend < 0.05). These dose-dependent trends remained suggestive or significant after controlling for multiple testing and other metals, and they persisted when the metals were modeled as continuous variables in a cubic spline analysis. There were no significant associations between urinary metals and sperm DNA damage after adjustment for multiple testing. Conclusion Environmental exposure to tin, nickel, zinc and molybdenum may be associated decreased total T or total T/LH ratio; manganese may induce spermatozoa apoptosis, while iron may be important for living spermatozoa. However, additional prospective research is needed to corroborate these findings in the general population. [ABSTRACT FROM AUTHOR]