Tumor cells produce vascular endothelial growth factor (VEGF) which interact with the membrane or cytoplasmic VEGF receptors (VEGFRs) to promote cell growth in an angiogenesis-independent fashion. Apatinib, a highly selective VEGFR2 inhibitor, is the only effective drug for patients with terminal gastric cancer (GC) who have no other chemotherapeutic options. However, its treatment efficacy is still controversy and the mechanism behind remains undetermined. In this study, we aimed to investigate the role of autocrine VEGF signaling in the growth of gastric cancer cells and the efficacy of Apatinib treatment.The expression of phosphor VEGFR2 in gastric cancer cell lines was determined by real-time PCR, immunofluorescence, and Western blot. The gastric cancer cells were administrated with or without recombination human VEGF (rhVEGF), VEGFR2 neutralizing antibody, U73122, SU1498, and Apatinib. The nude mice were used for xenograft tumor model.we found that autocrine VEGF induced high VEGFR2-expression, promoted phosphorylation of VEGFR2, and further enhanced internalization of pVEGFR2 in gastric cancer cells. The autocrine VEGF was self-sustained through increasing VEGF mRNA and protein expression. It exerted pro-proliferative effect through a PLC-ERK1/2 dependent pathway. Furthermore, we demonstrated that in VEGFR2 overexpressing gastric cancer cells, Apatinib inhibited cell proliferation in vitro and delayed xenograft tumor growth in vivo. However, these effects were not observed in VEGFR2 low expressing gastric cancer cells.These results suggested that autocrine VEGF signaling promotes gastric cancer cell proliferation and enhances Apatinib treatment outcome in VEGFR2 overexpression gastric cancer cells both in vitro and in vivo. This study would enable better stratification of gastric cancer patients for clinical treatment decision.
Macrophages regulate the inflammatory response and affect re-endothelialization. Inflammation and macrophages play important roles in promoting tissue repair, but p38α mitogen-activated protein kinase's role in re-endothelialization is unknown. Wire injuries of carotid arteries and Evans blue staining were performed in macrophage-specific p38α-knockout (p38αfl/flLysMCre+/-) mice and control mice (p38αfl/fl). Re-endothelialization of the carotid arteries at 3, 5 and 7 days was significantly promoted in p38αfl/flLysMCre+/- mice. In vitro experiments indicated that both the proliferation and migration of endothelial cells were enhanced in conditioned medium from peritoneal macrophages of p38αfl/flLysMCre+/- mice. Interleukin-6 (IL-6) level was decreased significantly in macrophages of p38αfl/flLysMCre+/- mice and an IL-6-neutralizing antibody promoted endothelial cell migration in vitro and re-endothelialization in p38αfl/fl mice in vivo. Phosphoproteomics revealed that the phosphorylation level of S544/T545/S549 sites in megakaryocytic leukemia 1 (MKL1) was decreased in p38αfl/flLysMCre+/- mice. The mutation of either S544/S549 or T545/S549 sites could reduce the expression of IL-6 and the inhibition of MKL1 reduced the expression of IL-6 in vitro and promoted re-endothelialization in vivo. p38α in macrophages aggravates injury of arteries by phosphorylating MKL1, and increasing IL-6 expression after vascular injury.
Abstract Like a winter jasmine in full bloom, the experience of Dajing Middle School brought to people the message of spring on the educational front. Under the auspices of the Education Bureau, some comrades from elementary and secondary schools went in succession to visit and learn from Dajing Middle School. Among them were principals of key middle schools, secretaries of party branches, teachers of special grades, and teachers in charge of slow learners' classes. After visiting Dajing, they couldn't help gasping in admiration, "It's truly remarkable!"
Abstract We isolated and expanded fibroblast‐like cells from the Wharton's jelly of human umbilical cord successfully. Immunocytochemistry showed that they were positive for several markers of mesenchymal stem cells (CD73, CD90, and CD105) and integrin markers (CD29 and CD44), but negative for a hematopoietic cell maker (CD45) and an endothelial cell marker (CD31). Their differentiation into osteocytes and adipocytes under specific conditions indicated that they had multi‐lineage differentiation potential. Therefore these results proved that the cells we obtained from Wharton's jelly were human umbilical cord mensenchymal stem cells (hUCMSCs). Using immunocytochemistry and Western blotting analysis, we found that after treatment with neuronal induction medium [NIM; consisting of brain‐derived neurotrophic factor (BDNF) and low‐serum media] for 14 days, hUCMSCs expressed a neuronal specific marker, microtubule associated protein 2 (MAP2), and extended neurite‐like processes. After treatment with NIM, supplemented with hippocampal cholinergic neurostimulating peptide (HCNP) or rat denervated hippocampal extract [rDHE; derived from rat fimbria fornix (FF) transected hippocampus], hUCMSCs expressed choline acetytransferase (ChAT) and this action could be enhanced when cells were cultured with NIM, supplemented with HCNP and rDHE in combination. ELISA showed that these ChAT‐positive cells could secrete acetylcholine (ACh). These findings indicate that hUCMSCs possess the potential of differentiation into functional ChAT‐positive cells in vitro and provide a new candidate of cells for the cell transplantation to treat Alzheimer's disease (AD).
Group B streptococcus (GBS) is a leading cause of serious infection in infants. Understanding its regional molecular epidemiology is helpful for regulating efficient prevention practice. A retrospective study was conducted to collected data from infants and pregnant women with culture-proven GBS disease in the largest women and children's medical center in Shanxi between January 2017 and September 2019. All GBS isolates were analyzed by multi-locus sequence typing (MLST) as well as distribution of pilus island (PI) genes. A total of 54 GBS isolates were obtained from 36 (66.7%) pregnant women and 18 (33.3%) infants with invasive disease. Among invasive GBS strains, the most common sequence type was ST10 (72.2%, P < 0.05), followed by ST23 and ST19. The ST10 strain was also the leading sequence type in colonizing pregnant women (44.4%, P < 0.05). All of the isolates carried at least one pilus island. The most frequently detected pilus island was PI-1+PI-2a (85.2%, P < 0.05), followed in turn by PI-2a and PI-2b. Our study demonstrates that one hypervirulent clone, sequence type 10, accounts for a large proportion of invasive GBS disease in infants and colonizing pregnant women, and the PI-1+PI-2a sub-lineages should be noted in infant infections.