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We have previously reported that enhanced excitability of dorsal root ganglia (DRG) neurons contributes to the development of bone cancer pain, which severely decreases the quality of life of cancer patients. Nav1.8, a tetrodotoxin-resistant (TTX-R) sodium channel, contributes most of the sodium current underlying the action potential upstroke and accounts for most of the current in later spikes in a train. We speculate that the Nav1.8 sodium channel is a potential candidate responsible for the enhanced excitability of DRG neurons in rats with bone cancer pain. Here, using electrophysiology, Western blot and behavior assays, we documented that the current density of TTX-R sodium channels, especially the Nav1.8 channel, increased significantly in DRG neurons of rats with cancer-induced bone pain. This increase may be due to an increased expression of Nav1.8 on the membrane of DRG neurons. Accordantly, blockade of Nav1.8 sodium channels by its selective blocker A-803467 significantly alleviated the cancer-induced mechanical allodynia and thermal hyperalgesia in rats. Taken together, these results suggest that functional upregulation of Nav1.8 channels on the membrane of DRG neurons contributes to the development of cancer-induced bone pain.

Accumulating evidence indicate that macrophages activate mesenchymal stem cells (MSCs) to acquire pro-inflammatory phenotype. However, the role of MSCs activated by macrophages in gastric cancer remains largely unknown. In this study, we found that MSCs were activated by macrophages to produce increased levels of inflammatory cytokines. Cell colony formation and transwell migration assays revealed that supernatants from the activated MSCs could promote both gastric epithelial cell and gastric cancer cell proliferation and migration. In addition, the expression of epithelial-mesenchymal transition (EMT), angiogenesis, and stemness-related genes was increased in activated MSCs. The phosphorylated forms of NF-κB, ERK and STAT3 in gastric cells were increased by active MSCs. Inhibition of NF-κB activation by PDTC blocked the effect of activated MSCs on gastric cancer cells. Co-injection of activated MSCs with gastric cancer cells could accelerate gastric cancer growth. Moreover, human peripheral blood monocytes derived macrophages also activated MSCs to prompt gastric cancer cell proliferation and migration. Taken together, our findings suggest that MSCs activated by macrophage acquire pro-inflammatory phenotype and prompt gastric cancer growth in an NF-κB-dependent manner, which provides new evidence for the modulation of MSCs by tumor microenvironment and further insight to the role of stromal cells in gastric carcinogenesis and cancer progression.

Paclitaxel is a microtubule stabilizing drug that causes dividing cells to arrest and then undergo apoptosis. It also has antiangiogenic activity because it alters cytoskeletal structure, affecting migration and invasion. Paclitaxel is an effective treatment for AIDS-related Kaposi’s sarcoma (KS). KS is a tumor in which there is marked proliferation of endothelial cells in addition to the tumor cells, which themselves share many markers with activated (proliferating) endothelial cells.We sought to determine the mechanism by which paclitaxel exerts its anti-KS tumor effects. In vitro, KS cells are very sensitive to paclitaxel, with half-maximal growth inhibition observed at 0.8 nM. Inhibition of migration of KS cells was also observed at nanomolar concentrations of the drug. Paclitaxel induced cell cycle arrest with an accumulation of cells in sub-G1.This was accompanied in vitro by various events typical of apoptosis: phosphorylation of two anti-apoptotic proteins Bcl-2 and Bcl-xL , release of cytochrome c into the cytoplasm, cleavage and activation of caspase-3. In vitro results were borne out by studies of KS tumor xenografts in nude mice. Paclitaxel (10 mg/kg) inhibited tumor growth by 75% over 21 days. Histological examination of the tumors revealed a decrease in proliferative index, a decrease in the number of mitotic figures and an increase in apoptotic cells compared to tumors from untreated mice.

Recently, we have demonstrated that trichosanthin (TCS), a promising agent for the treatment of cervical adenocarcinoma, inhibited HeLa cell proliferation through the PKC/MAPK/CREB signal pathway. Furthermore, TCS down-regulated Bcl-2 expression was abrogated by a decoy oligonucleotide (OGN) to the cyclic AMP-responsive element (CRE). The decoy OGN blocked the binding of CRE-binding protein (CREB) to Bcl-2. These results suggested that CRE-mediated gene expression may play a pivotal role in HeLa cell proliferation. However, little is known about the effect of TCS on cell cycle arrests, particularly, whether the genes involved in cell cycle were regulated by CRE. Our present study shows that the arrests of S, G1 and G2/M phases were accompanied by the significant down-regulation of cyclin A, D1 and CDK 2, 4 in HeLa cells, cyclin D1, E and CDK 2, 4 in Caski and C33a cells, and cyclin A, B1, E and CDK 2 in SW1990 cells. However, the cell cycle arrests were reversed via the significant up-regulation of cyclin A and D1, by the combined treatment of TCS and CRE. In conclusion, these data demonstrate for the first time that specific cell cycle arrests in cancer cells can be induced by TCS by inhibiting the binding of CREB to CRE on genes related to cell proliferation.

Fibrodysplasia ossificans progressiva (FOP) is a rare heritable disease characterized by progressive heterotopic ossification of connective tissues, for which there is presently no definite treatment. A recurrent activating mutation (c.617G→A; R206H) of activin receptor-like kinase 2 (ACVR1/ALK2), a BMP type I receptor, has been shown as the main cause of FOP. This mutation constitutively activates the BMP signaling pathway and initiates the formation of heterotopic bone. In this study, we have designed antisense oligonucleotides (AONs) to knockdown mouse ALK2 expression by means of exon skipping. The ALK2 AON could induce exon skipping in cells, which was accompanied by decreased ALK2 mRNA levels and impaired BMP signaling. In addition, the ALK2 AON potentiated muscle differentiation and repressed BMP6-induced osteoblast differentiation. Our results therefore provide a potential therapeutic approach for the treatment of FOP disease by reducing the excessive ALK2 activity in FOP patients.

Osteogenic differentiation of human mesenchymal stem cells (hMSCs) is regulated by multiple transcription factors and signaling molecules. However, the molecular mechanisms underlying this process remain to be fully elucidated. MicroRNAs (miRNAs) act as key regulators in various biological processes by mediating mRNA degradation or translational inhibition of target genes. In this study, we report that miR-346 plays critical roles in regulating osteogenic differentiation of hBMSCs. The expression of endogenous miR-346 was increased during osteogenic differentiation of hBMSCs. Overexpression of miR-346 significantly promoted osteogenic differentiation, whereas miR-346 depletion suppressed this process. Further studies confirmed that miR-346 directly targeted the 3'-UTR of the glycogen synthase kinase-3β (GSK-3β) gene so as to suppress the expression of GSK-3β protein. Similar to miR-346 overexpression, GSK-3β depletion promoted osteogenic differentiation, whereas GSK-3β overexpression reversed the promotional effect of miR-346. We further found that miR-346 overexpression activated the Wnt/β-catenin pathway and increased the expression of several downstream genes including CyclinD1, c-Myc, TCF-1 and LEF-1. Depletion of β-catenin almost completely blocked the positive role of miR-346 on osteogenic differentiation. Taken together, our data indicate that miR-346 positively regulates hBMSC osteogenic differentiation by targeting GSK-3β and activating the Wnt/β-catenin pathway.

BACKGROUND: Bone cancer pain seriously affects the quality of life of cancer patients. Our previous study found that endogenous formaldehyde was produced by cancer cells metastasized into bone marrows and played an important role in bone cancer pain. However, the mechanism of production of this endogenous formaldehyde by metastatic cancer cells was unknown in bone cancer pain rats. Lysine-specific demethylase 1 (LSD1) is one of the major enzymes catalyzing the production of formaldehyde. The expression of LSD1 and the concentration of formaldehyde were up-regulated in many high-risk tumors. OBJECTIVE: This study aimed to investigate whether LSD1 in metastasized MRMT-1 breast cancer cells in bone marrows participated in the production of endogenous formaldehyde in bone cancer pain rats. METHODOLOGY/PRINCIPAL FINDINGS: Concentration of the endogenous formaldehyde was measured by high performance liquid chromatography (HPLC). Endogenous formaldehyde dramatically increased in cultured MRMT-1 breast cancer cells in vitro, in bone marrows and sera of bone cancer pain rats, in tumor tissues and sera of MRMT-1 subcutaneous vaccination model rats in vivo. Formaldehyde at a concentration as low as the above measured (3 mM) induced pain behaviors in normal rats. The expression of LSD1 which mainly located in nuclei of cancer cells significantly increased in bone marrows of bone cancer pain rats from 14 d to 21 d after inoculation. Furthermore, inhibition of LSD1 decreased the production of formaldehyde in MRMT-1 cells in vitro. Intraperitoneal injection of LSD1 inhibitor pargyline from 3 d to 14 d after inoculation of MRMT-1 cancer cells reduced bone cancer pain behaviors. CONCLUSION: Our data in the present study, combing our previous report, suggested that in the endogenous formaldehyde-induced pain in bone cancer pain rats, LSD1 in metastasized cancer cells contributed to the production of the endogenous formaldehyde.

In the structure of the title compound, C37H40N4O8, pentaerythrityltetramine is bonded to four o-vanillin molecules, forming a four-armed Schiff base molecule. These molecules are connected by intermolecular C—H...O hydrogen bonds. Intramolecular C—H...N and O—H...N hydrogen bonds are also present.

Abstract Background Hepatitis B virus (HBV) is still one of the serious infectious risks for the blood transfusion safety in China. One plausible reason is the emergence of the variants in the major antigenic alpha determinant within the major hydrophilic region (MHR) of hepatitis B surface antigen (HBsAg), which have been assumed to evade the immune surveillance and pose a challenge to the disease diagnosis. It is well documented that some commercial ELISA kits could detect the wild-type but not the mutant viruses. The high prevalence of HBV in China also impaired the application of nucleic acid testing (NAT) in the improvement of blood security. Molecular epidemiological study of HBsAg variations in China is still limited. This study was designed to identify the prevalence of mutations in the HBsAg in voluntary blood donors in Nanjing, China. Methods A total of 20,326 blood units were enrolled in this study, 39 donors were positive for HBV S gene in the nested-PCR. Mutations in the major hydrophilic region (MHR; aa 99-169) were identified by direct sequencing of S region. Results Among of 20,326 blood units in the Red Cross Transfusion Center of Nanjing from October 2008 to April 2009, 296 samples (1.46%, 296/20,326) were HBsAg positive in the 2 successive rounds of the ELISA test. In these HBsAg positive units, HBV S gene could be successfully amplified from 39 donors (13.18%, 39/296) in the nested-PCR. Sequence analysis revealed that 32 strains (82.1%, 32/39) belong to genotype B, 7 strains (17.9%, 7/39) to genotype C. Besides well known G145R, widely dispersed variations in the MHR of S region, were observed in 20 samples of all the strains sequenced. Conclusions HBV/B and HBV/C are dominant in Nanjing, China. The mutations in the MHR of HBsAg associated with disease diagnosis are common.

Purpose • This study systematically assesses the correlation between asymptomatic endometrial thickening after the age of 50 and the risk of endometrial cancer (EC). Methods • A comprehensive search was conducted using the Cochrane Library, Web of Science, PubMed, ProQuest, and Chinese biomedical literature databases Wanfang, Weipu, and CNG until August 2022. The included literature was analyzed using RevMan 5.3 software to explore heterogeneity in each study. Results • Five studies were finally included. The assessment of odds ratio (OR) heterogeneity between women with endometrial thickening and the risk of EC showed P = .18, I2=95%, indicating significant heterogeneity. A random- effects model was applied for meta-analysis, revealing a result of 0.96, 95% CI (0.92, 1.02), P = .18, indicating no statistical significance between the two groups (P > .05). The funnel plot demonstrated asymmetry, suggesting evident publication bias. Conclusion • There is no consistent correlation between asymptomatic endometrial thickening and the occurrence of EC in individuals over 50 years of age. [ABSTRACT FROM AUTHOR]