RY10-4 Inhibits the Proliferation of Human Hepatocellular Cancer HepG2 Cells by Inducing Apoptosis In Vitro and In Vivo

This study aimed to investigate the anti-tumor activity of RY10-4, a small molecular that was designed and synthesized based on the structure of protoapigenone. A previous screening study showed that RY10-4 possessed anti-proliferative effects against HepG2 human hepatocellular carcinoma cells. However, the full range of RY10-4 anti-cancer effects on liver tumors and the underlying mechanisms have not been identified. Herein, employing flow cytometry, and Western blot analysis, we demonstrate that RY10-4 can induce cell cycle arrest, intracellular reactive oxygen species (ROS) production and apoptosis in HepG2 cells. In HepG2 cell xenograft tumor model, RY10-4 significantly inhibited the growth of tumors and induced apoptosis in tumor cells, with little side effects. Moreover, RY10-4 caused the suppression of STAT3 activation, which may be involved the apoptosis induction. In addition, RY10-4 inhibited the proliferation of Hep3B and HuH-7 human hepatocellular carcinoma cells in a concentration-dependent manner. Taken together, our results suggest that RY10-4 has a great potential to develop as chemotherapeutic agent for liver cancer.     

DNA Methyltransferase Inhibitor Zebularine Inhibits Human Hepatic Carcinoma Cells Proliferation and Induces Apoptosis

Hepatocellular carcinoma is one of the most common cancers worldwide. During tumorigenesis, tumor suppressor and cancer-related genes are commonly silenced by aberrant DNA methylation in their promoter regions. Zebularine (1-(β-_D-ribofuranosyl)-1,2-dihydropyrimidin-2-one) acts as an inhibitor of DNA methylation and exhibits chemical stability and minimal cytotoxicity both in vitro and in vivo. In this study, we explore the effect and possible mechanism of action of zebularine on hepatocellular carcinoma cell line HepG2. We demonstrate that zebularine exhibits antitumor activity on HepG2 cells by inhibiting cell proliferation and inducing apoptosis, however, it has little effect on DNA methylation in HepG2 cells. On the other hand, zebularine treatment downregulated CDK2 and the phosphorylation of retinoblastoma protein (Rb), and upregulated p21^WAF/CIP1 and p53. We also found that zebularine treatment upregulated the phosphorylation of p44/42 mitogen-activated protein kinase (MAPK). These results suggest that the p44/42 MAPK pathway plays a role in zebularine-induced cell-cycle arrest by regulating the activity of p21^WAF/CIP1 and Rb. Furthermore, although the proapoptotic protein Bax levels were not affected, the antiapoptotic protein Bcl-2 level was downregulated with zebularine treatment. In addition, the data in the present study indicate that inhibition of the double-stranded RNA-dependent protein kinase (PKR) is involved in inducing apoptosis with zebularine. These results suggest a novel mechanism of zebularine-induced cell growth arrest and apoptosis via a DNA methylation-independent pathway in hepatocellular carcinoma.     

Doxycycline Induces Apoptosis and Inhibits Proliferation and Invasion of Human Cervical Carcinoma Stem Cells

BackgroundCancer stem cells (CSCs) are proposed to be responsible for high recurrence rate in cervical carcinoma. Reagents that can suppress the proliferation and differentiation of CSCs would provide new opportunities to fight against tumor recurrence. Doxycycline has been reported as a potential anti-cancer compound. However, few studies investigated its inhibitory effect against cervical cancer stem cells.MethodsHeLa cells were cultured in cancer stem cell conditional media in a poly-hema-treated dish. In this non-adhesive culture system, HeLa cells were treated with cisplatin until some cells survived and formed spheroids, which were then collected and injected into the immunodeficient mice. Cisplatin was administered every three days for five times. The tumor xenografts with CSC enrichment were cultured in cancer stem cell specific medium again to form tumorsphere, which we called HeLa-CSCs. Expression of cancer stem cell markers in HeLa-CSCs was measured by flow cytometry and qPCR. HeLa-CSCs were then treated with doxycycline. Proliferation and differentiation rates were determined by the size of spheres formed in vitro and tumor formed in vivo.ResultsWe developed a new strategy to selectively enrich CSCs from human cervical carcinoma cell line HeLa, and these HeLa-CSCs are CD133+/CD49f+ cell populations with significantly enhanced expression of stem cell markers. When these HeLa-CSCs were treated with doxycycline, the colony formation, proliferation, migration and invasion, and differentiation were all suppressed. Meanwhile, stem cell markers SOX-2, OCT-4, NANOG, NOTCH and BMI-1 decreased in doxycycline treated cells, so as the surface markers CD133 and CD49f. Furthermore, proliferation markers Ki67 and PCNA were also decreased by doxycycline treatment in the in vivo xenograft mouse model.ConclusionsCancer stem cells are enriched from sphere-forming and chemoresistant HeLa-derived tumor xenografts in immunodeficient mice. Doxycycline inhibits proliferation, invasion, and differentiation, and also induces apoptosis of these HeLa-CSCs in vitro and in vivo.     

Human but Not Laboratory Borna Disease Virus Inhibits Proliferation and Induces Apoptosis in Human Oligodendrocytes In Vitro

Borna disease virus (BDV) is a neurotropic virus that produces neuropsychiatric dysfunction in a wide range of warm-blooded species. Several studies have associated BDV with human psychiatric illness, but the findings remain controversial. Although oligodendrocytes are a major glial component of brain white matter and play a pivotal role in neuronal cell function, BDV''s effects on human oligodendrocytes have not been clarified. Here, the effects of two BDV strains, Hu-H1 (isolated from a bipolar patient) and Strain V (a laboratory strain), on the proliferation and apoptosis of human oligodendrocytes were investigated. Three experimental cell lines were constructed: Hu-H1-infected oligodendroglioma (Hu-H1) cells, Strain V-infected oligodendroglioma (Strain V) cells, and non-infected oligodendroglioma (control) cells. BDV infection was assayed by BDV nucleoprotein (p40) immunofluorescence, cell proliferation was assayed by Cell Counting Kit-8 (CCK8), and cell cycle phases and apoptosis were assayed by flow cytometry. Expressions of the apoptosis-related proteins Bax and Bcl-2 were measured by Western blotting. p40 expression was confirmed in Hu-H1 and Strain V on and after day three post-infection. Strain V cells showed significantly greater cellular proliferation than Hu-H1 cells on and after day three post-infection. In Hu-H1 cells, Bax and Bcl-2 expression were significantly increased and decreased, respectively, on and after day three post-infection. In contrast, in Strain V cells, Bax and Bcl-2 expression were significantly decreased and increased, respectively, on and after day three post-infection. In conclusion, Hu-H1 inhibits cellular proliferation and promotes apoptosis in human oligodendrocytes via Bax upregulation and Bcl-2 downregulation. In contrast, Strain V promotes cellular proliferation and inhibits apoptosis in human oligodendrocytes via Bax downregulation and Bcl-2 upregulation. The effects of the Hu-H1 strain (isolated from a bipolar patient) are opposite from those of Strain V (a laboratory strain), thereby providing a proof of authenticity for both.     

二氢青蒿素通过诱导铁死亡抑制肝癌细胞生长

二氢青蒿素（dihydroartemisinin,DHA）是青蒿素的一种衍生物,在多种肿瘤中表现出明显的抗肿瘤活性,但其具体机制不详。本文探讨了DHA对肝癌细胞的毒性作用机制。利用CCK-8试剂检测DHA对肝癌细胞株活力的影响,通过荧光探针染色及流式细胞术分析细胞内ROS及脂质过氧化物水平的变化;通过谷胱甘肽测定试剂盒检测细胞内还原型谷胱甘肽含量的变化,并通过免疫印迹分析DHA作用下细胞内铁死亡通路蛋白质中GPX4的变化。结果发现,DHA能显著抑制SMMC-7721及Huh-7细胞活力,其半数抑制浓度分别为23.74 μmol/L及26.92 μmol/L。 在35 μmol/L DHA 处理下,SMMC-7721及Huh-7细胞内ROS分别升高2.6倍和2.1倍,脂质过氧化物升高2.3倍和1.7倍。DHA可诱导细胞内GSH含量下降,并能下调铁死亡相关蛋白质GPX4蛋白水平。通过利用小分子抑制剂进行功能恢复实验发现,ROS抑制剂、铁螯合剂及铁死亡抑制剂都可不同程度恢复DHA引起的细胞活力下降。进一步检测发现,铁死亡抑制剂可抑制DHA诱导的脂质过氧化,并恢复GSH含量及GPX4蛋白水平。结果表明,在肝癌细胞中,DHA可通过诱导细胞发生铁死亡抑制肝癌细胞生长。     

二氢青蒿素通过诱导铁死亡抑制肝癌细胞生长

二氢青蒿素（dihydroartemisinin,DHA）是青蒿素的一种衍生物,在多种肿瘤中表现出明显的抗肿瘤活性,但其具体机制不详。本文探讨了DHA对肝癌细胞的毒性作用机制。利用CCK-8试剂检测DHA对肝癌细胞株活力的影响,通过荧光探针染色及流式细胞术分析细胞内ROS及脂质过氧化物水平的变化;通过谷胱甘肽测定试剂盒检测细胞内还原型谷胱甘肽含量的变化,并通过免疫印迹分析DHA作用下细胞内铁死亡通路蛋白质中GPX4的变化。结果发现,DHA能显著抑制SMMC-7721及Huh-7细胞活力,其半数抑制浓度分别为23.74 μmol/L及26.92 μmol/L。 在35 μmol/L DHA 处理下,SMMC-7721及Huh-7细胞内ROS分别升高2.6倍和2.1倍,脂质过氧化物升高2.3倍和1.7倍。DHA可诱导细胞内GSH含量下降,并能下调铁死亡相关蛋白质GPX4蛋白水平。通过利用小分子抑制剂进行功能恢复实验发现,ROS抑制剂、铁螯合剂及铁死亡抑制剂都可不同程度恢复DHA引起的细胞活力下降。进一步检测发现,铁死亡抑制剂可抑制DHA诱导的脂质过氧化,并恢复GSH含量及GPX4蛋白水平。结果表明,在肝癌细胞中,DHA可通过诱导细胞发生铁死亡抑制肝癌细胞生长。     

Maduramicin Inhibits Proliferation and Induces Apoptosis in Myoblast Cells

Maduramicin, a polyether ionophore antibiotic derived from the bacterium Actinomadura yumaensis, is currently used as a feed additive against coccidiosis in poultry worldwide. It has been clinically observed that maduramicin can cause skeletal muscle and heart cell damage, resulting in skeletal muscle degeneration, heart failure, and even death in animals and humans, if improperly used. However, the mechanism of its toxic action in myoblasts is not well understood. Using mouse myoblasts (C2C12) and human rhabdomyosarcoma (RD and Rh30) cells as an experimental model for myoblasts, here we found that maduramicin inhibited cell proliferation and induced cell death in a concentration-dependent manner. Further studies revealed that maduramicin induced accumulation of the cells at G₀/G₁ phase of the cell cycle, and induced apoptosis in the cells. Concurrently, maduramicin downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and CDC25A, and upregulated expression of the CDK inhibitors (p21^Cip1 and p27^Kip1), resulting in decreased phosphorylation of Rb. Maduramicin also induced expression of BAK, BAD, DR4, TRADD and TRAIL, leading to activation of caspases 8, 9 and 3 as well as cleavage of poly ADP ribose polymerase (PARP). Taken together, our results suggest that maduramicin executes its toxicity in myoblasts at least by inhibiting cell proliferation and inducing apoptotic cell death.     

AMP-Activated Protein Kinase Suppresses the In Vitro and In Vivo Proliferation of Hepatocellular Carcinoma

AMP-activated protein kinase (AMPK) is a central metabolic sensor and plays an important role in regulating glucose, lipid and cholesterol metabolism. Therefore, AMPK is a key therapeutic target in diabetes. Recent pilot studies have suggested that diabetes drugs may reduce the risk of cancer by affecting the AMPK pathway. However, the association between AMPK and the proliferation of hepatocellular carcinoma (HCC) is unknown. In this study, we investigated the relationship between AMPK activity and the proliferation of HCC in cell lines, nude mice and human clinic samples. We first investigated the relationship between AMPK activity and cell proliferation in two HCC cell lines, PLC/PRF/5 and HepG2, by two AMPK activators, 5-aminoimidazole-4-carboxamide-1-h-D-ribofuranoside (AICAR) and metformain. AICAR and metformin treatment significantly inhibited the proliferation of HCC cells and induced cell cycle arrest at G1-S checkpoint. We then observed that metformin abrogated the growth of HCC xenografts in nude mice. The clinical pathology of AMPK activity in HCC, including cell proliferation, differential grade, tumor size and microvessel density, was studied by using 30 clinical tissue samples. In HCC tissue samples, phosphorylated AMPK was expressed mainly in cytoplasm. AMPK activity decreased significantly in HCC in comparison with paracancerous liver tissues (P<0.05). AMPK activity was negatively correlated with the level of Ki-67 (a marker of cell proliferation), differential degradation and tumor size (P<0.05), but not with microvessel density, hemorrhage or necrosis in HCC. Our findings suggest that AMPK activity inhibits the proliferation of HCC and AMPK might be an effective target for prevention and treatment of HCC.     

Xanthohumol Inhibits Notch Signaling and Induces Apoptosis in Hepatocellular Carcinoma

Despite improvement in therapeutic strategies, median survival in advanced hepatocellular carcinoma (HCC) remains less than one year. Therefore, molecularly targeted compounds with less toxic profiles are needed. Xanthohumol (XN), a prenylated chalcone has been shown to have anti-proliferative effects in various cancers types in vitro. XN treatment in healthy mice and humans yielded favorable pharmacokinetics and bioavailability. Therefore, we determined to study the effects of XN and understand the mechanism of its action in HCC. The effects of XN on a panel of HCC cell lines were assessed for cell viability, colony forming ability, and cellular proliferation. Cell lysates were analyzed for pro-apoptotic (c-PARP and cleaved caspase-3) and anti-apoptotic markers (survivin, cyclin D1, and Mcl-1). XN concentrations of 5μM and above significantly reduced the cell viability, colony forming ability and also confluency of all four HCC cell lines studied. Furthermore, growth suppression due to apoptosis was evidenced by increased expression of pro-apoptotic and reduced expression of anti-apoptotic proteins. Importantly, XN treatment inhibited the Notch signaling pathway as evidenced by the decrease in the expression of Notch1 and HES-1 proteins. Ectopic expression of Notch1 in HCC cells reverses the anti-proliferative effect of XN as evidenced by reduced growth suppression compared to control. Taken together these results suggested that XN mediated growth suppression is appeared to be mediated by the inhibition of the Notch signaling pathway. Therefore, our findings warrants further studies on XN as a potential agent for the treatment for HCC.     

Baohuoside I Inhibits the Proliferation of Hepatocellular Carcinoma Cells via Apoptosis Signaling and NF-kB Pathway

Baohuoside I is a flavonoid isolated from Epimedium koreanum Nakai and has many pharmacological activities. However, its role in liver cancer remains unclear. This study aimed to investigate the inhibitory effect of Baohuoside I on the Human Hepatocellular Carcinoma (HCC) cell lines QGY7703, and underlying mechanisms. QGY7703 cells were used as the model to assess the function of Baohuoside I in vitro. The effects of Baohuoside I on QGY7703 cells’ growth, proliferation, and invasiveness were confirmed by CCK-8, lactate dehydrogenase release, and invasion assays. Cell apoptosis was analyzed by flow cytometry, and the levels of cleaved Caspase-3, Bax, and Bcl-2 were quantified by western blot. Western blot analysis, nuclear translocation of NF-κB, and Q-PCR were used to measure the expression of affected molecules. In QGY7703 cells, Baohuoside I induced the expression of molecules related to NF-κB pathway. The toxicity of Baohuoside I on QGY7703 cells was also confirmed in vivo, in a tumor model. Baohuoside I had a significant toxic effect on QGY7703 cells from a concentration of 10 μM. This compound significantly inhibited the proliferation of QGY7703 cells by inducing apoptosis and downregulating NF-κB signaling pathway. Thus, Baohuoside I is a novel candidate drug and opens new possibilities of clinical strategies for HCC treatment.     

Aciculatin Induces p53-Dependent Apoptosis via MDM2 Depletion in Human Cancer Cells In Vitro and In Vivo

Aciculatin, a natural compound extracted from the medicinal herb Chrysopogon aciculatus, shows potent anti-cancer potency. This study is the first to prove that aciculatin induces cell death in human cancer cells and HCT116 mouse xenografts due to G1 arrest and subsequent apoptosis. The primary reason for cell cycle arrest and cell death was p53 accumulation followed by increased p21 level, dephosphorylation of Rb protein, PUMA expression, and induction of apoptotic signals such as cleavage of caspase-9, caspase-3, and PARP. We demonstrated that p53 allele-null (-/-) (p53-KO) HCT116 cells were more resistant to aciculatin than cells with wild-type p53 (+/+). The same result was achieved by knocking down p53 with siRNA in p53 wild-type cells, indicating that p53 plays a crucial role in aciculatin-induced apoptosis. Although DNA damage is the most common event leading to p53 activation, we found only weak evidence of DNA damage after aciculatin treatment. Interestingly, the aciculatin-induced downregulation of MDM2, an important negative regulator of p53, contributed to p53 accumulation. The anti-cancer activity and importance of p53 after aciculatin treatment were also confirmed in the HCT116 xenograft models. Collectively, these results indicate that aciculatin treatment induces cell cycle arrest and apoptosis via inhibition of MDM2 expression, thereby inducing p53 accumulation without significant DNA damage and genome toxicity.     

The Synergistic In Vitro and In Vivo Antitumor Effect of Combination Therapy with Salinomycin and 5-Fluorouracil against Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the few cancers in which a continuous increase in incidence has been observed over several years. Drug resistance is a major problem in the treatment of HCC. In the present study, we used salinomycin (Sal) and 5-fluorouracil (5-FU) combination therapy on HCC cell lines Huh7, LM3 and SMMC-7721 and nude mice subcutaneously tumor model to study whether Sal could increase the sensitivity of hepatoma cells to the traditional chemotherapeutic agent such as 5-FU. The combination of Sal and 5-FU resulted in a synergistic antitumor effect against liver tumors both in vitro and in vivo. Sal reversed the 5-FU-induced increase in CD133(+) EPCAM(+) cells, epithelial–mesenchymal transition and activation of the Wnt/β-catenin signaling pathway. The combination of Sal and 5-FU may provide us with a new approach to reverse drug resistant for the treatment of patients with HCC.     

盐霉素抑制人肝细胞癌转移与侵袭的体外与体内实验研究

目的：肝癌的转移与复发是肝癌治疗的一大难题,盐霉素是近年来新发现的具有抗肿瘤作用的抗生素,本文研究了盐霉素在体外及体内对人肝细胞癌转移与侵袭能力的作用及机制。方法：在体外对肝癌细胞株HepG2,SMMC-7721,BEL-7402给予盐霉素处理,体内建立裸鼠肝脏原位肿瘤模型,并给予腹腔注射盐霉素治疗。观察肿瘤细胞的转移侵袭能力以及肝内肿瘤转移灶的情况,进一步测定E．cadherin,Vimentin的表达,来研究盐霉素对肝癌转移及侵袭能力的影响及机制。结果：经盐霉素处理后,肝癌细胞株HepG2,SMMC．7721,BEL．7402的转移及侵袭能力明显下降,肝内转移灶的数目也减少。分子机制检测发现盐霉素处理后E．cadherin表达增高,Vimentin表达下降。结论：盐霉素在体内与体外都抑制了肝癌的转移与侵袭,其机制可能抑制了肿瘤细胞的上皮间质化（EMT）过程。这为控制肝癌的转移和复发提供了新的治疗思路。     

Leflunomide Reduces Proliferation and Induces Apoptosis in Neuroblastoma Cells In Vitro and In Vivo

Leflunomide as an immunosuppressive drug is generally used in the treatment of rheumatoid arthritis. It inhibits DHODH (dihydroorotate dehydrogenase ), which is one of the essential enzymes in the de novo pyrimidine biosynthetic pathway. Here we showed that leflunomide significantly reduced cell proliferation and self-renewal activity. Annexin V-FITC/PI staining assay revealed that leflunomide induced S-phase cell cycle arrest, and promoted cell apoptosis. In vivo xenograft study in SCID mice showed that leflunomide inhibited tumor growth and development. We also observed that DHODH was commonly expressed in neuroblastoma. When treated with leflunomide, the neuroblastoma cell lines BE(2)-C, SK-N-DZ, and SK-N-F1 showed dramatic inhibition of DHODH at mRNA and protein levels. Considering the favorable toxicity profile and the successful clinical experience with leflunomide in rheumatoid arthritis, this drug represents a potential new candidate for targeted therapy in neuroblastoma.     

Pachymic Acid Inhibits Growth and Induces Apoptosis of Pancreatic Cancer In Vitro and In Vivo by Targeting ER Stress

Pachymic acid (PA) is a purified triterpene extracted from medicinal fungus Poria cocos. In this paper, we investigated the anticancer effect of PA on human chemotherapy resistant pancreatic cancer. PA triggered apoptosis in gemcitabine-resistant pancreatic cancer cells PANC-1 and MIA PaCa-2. Comparative gene expression array analysis demonstrated that endoplasmic reticulum (ER) stress was induced by PA through activation of heat shock response and unfolded protein response related genes. Induced ER stress was confirmed by increasing expression of XBP-1s, ATF4, Hsp70, CHOP and phospho-eIF2α. Moreover, ER stress inhibitor tauroursodeoxycholic acid (TUDCA) blocked PA induced apoptosis. In addition, 25 mg kg^-1 of PA significantly suppressed MIA PaCa-2 tumor growth in vivo without toxicity, which correlated with induction of apoptosis and expression of ER stress related proteins in tumor tissues. Taken together, growth inhibition and induction of apoptosis by PA in gemcitabine-resistant pancreatic cancer cells were associated with ER stress activation both in vitro and in vivo. PA may be potentially exploited for the use in treatment of chemotherapy resistant pancreatic cancer.     

Lipocalin-2 Induces Apoptosis in Human Hepatocellular Carcinoma Cells Through Activation of Mitochondria Pathways

Lipocalin 2 (LCN2) is a secreted, iron-binding glycoprotein that is abnormally expressed in some malignant human cancers. However, the roles of LCN2 in hepatocellular carcinoma (HCC) cells are unknown. In this study, we suggested the LCN2 and LCN2R were weak detected in the HCC cell lines, LCN2 and LCN2R were found to be down-regulated in tumor tissues in 16 HCC patients. MTT, DAPI, TUNEL, and flow cytometry analyses revealed that LCN2 overexpression dramatically inhibited cell viability, induced apoptosis features of cell-cycle arrest in sub-G1 phase, in DNA fragmentation, and in condensation of chromatin in Huh-7 and SK-Hep-1 cells. Western blots were used to detect the activation of caspase, pro-apoptosis, and anti-apoptosis protein expression in overexpress-LCN2 HCC cells. LCN2-induced apoptosis was characterized by cleavage of caspase-9, -8, -3, and PARP protein, and a reduction in the mitochondrial membrane potential (MMP). Furthermore, LCN2 also enhanced the down-regulated Bcl-2 and up-regulated the expression of Bax. In addition, our experiments with caspase inhibitors LEHD-FMK and IETD-FMK prevent LCN2-induced apoptosis. We also demonstrated that treatment of overexpress-LCN2 HCC cells with the LCN2 neutralized antibody also significantly attenuated LCN2-induced cell apoptosis. These findings indicate that LCN2 overexpression can effectively induce apoptosis of HCC cells and may be used as a potent therapy against human HCC.     

Knockdown of VEGFR2 Inhibits Proliferation and Induces Apoptosis in Hemangioma-Derived Endothelial Cells

Angiogenesis is a process of development and growth of new capillary blood vessels from pre-existing vessels. Angiogenic growth factors play important roles in the development and maintenance of some malignancies, of which vascular endothelial growth factor (VEGF)/VEGFR2 interactions are involved in proliferation, migration, and survival of many cancer cells. The aim of this study was to investigate the function of VEGFR2 in human hemangiomas (HAs). Using immunohistochemistry assay, we examined the expression levels of VEGF, VEGFR2, Ki-67, glucose transporter-1 (Glut-1), phosphorylated protein kinase B (p-AKT) and p-ERK in different phases of human HAs. Positive expression of VEGF, VEGFR2, Ki-67, Glut-1, p-AKT and p-ERK was significantly increased in proliferating phase HAs, while decreased in involuting phase HAs (P=0.001; P=0.003). In contrast, cell apoptotic indexes were decreased in proliferating phase HAs, but increased in involuting phase HAs (P<0.01). Furthermore, we used small hairpin RNA (shRNA)-mediated VEGFR2 knockdown in primary HA-derived endothelial cells (HemECs) to understand the role of VEGF/VEGFR2 signaling. Knockdown of VEGFR2 by Lv-shVEGFR2 inhibited cell viability and induced apoptosis in primary HemECs companied with decreased expression of p-AKT, p-ERK, p-p38MAPK and Ki-67 and increased expression of caspase-3 (CAS-3); Overexpression of VEGFR2 promoted cell viability and blocked apoptosis in Lv-VEGFR2-transfected HemECs. Taken together, our findings demonstrate that, increased expression of VEGFR2 is involved in the development of primary HemECs possibly through regulation of the AKT and ERK pathways, suggesting that VEGFR2 may be a potential therapeutic target for HAs.Key words: vascular endothelial growth factor receptor 2, hemangioma, proliferation, apoptosis     

Thymoquinone Inhibits Murine Leukemia WEHI-3 Cells In Vivo and In Vitro

BackgroundThymoquinone is an active ingredient isolated from Nigella sativa (Black Seed). This study aimed to evaluate the in vitro and in vivo anti-leukemic effects of thymoquinone on WEHI-3 cells.ConclusionThymoquinone promoted natural killer cell activities. This compound showed high toxicity against WEHI-3 cell line which was confirmed by an increase of the early apoptosis, followed by up-regulation of the anti-apoptotic protein, Bcl2, and down-regulation of the apoptotic protein, Bax. On the other hand, high reduction of the spleen and liver weight, and significant histopathology study of spleen and liver confirmed that thymoquinone inhibited WEHI-3 growth in the BALB/c mice. Results from this study highlight the potential of thymoquinone to be developed as an anti-leukemic agent.