Assessment of blended biochemistry classes based on massive open online courses and a "semi-flipped" learning environment.

Flipped classroom based on active learning is becoming an increasingly popular pedagogical method in higher education capable of increasing student performance in higher-order learning outcomes including application, analysis, evaluation, and creation. However, the success of a flipped classroom model relies on various supporting elements such as the accessibility of technology, and it may not be appropriate for all students and courses. In this study, a new blended biochemistry classroom model based on massive open online courses and a "semi-flipped" environment was applied to the students enrolled in three majors (stomatology, pharmacy, and preventive medicine) at Cheeloo College of Medicine, Shandong University, China. To assess the improvement of the students' perception of self-cognition in the blended biochemistry classes, surveys were conducted before and after undertaking the biochemistry course. Survey responses and total (final) score for the biochemistry course were analyzed using appropriate statistical methods. Compared to students who received traditional classroom instruction, students who participated in the blended classroom model achieved higher academic performance (p < 0.01) and reported a significant improvement in their perception of self-cognition (p < 0.01, or p < 0.05). More than 80% of participants preferred the blended classroom model to that of traditional classroom instruction.

How Do Blended Biochemistry Classes Influence Students' Academic Performance and Perceptions of Self-Cognition?

The flipped classroom is becoming a popular new instructional model in higher education capable of increasing student performance in higher-order learning outcomes. However, the success of a flipped classroom model depends on various supporting elements, and it may not be appropriate for all students and courses. In this study, a new blended Biochemistry classroom model based on Massive Open Online Courses (MOOC) and a "semi-flipped" environment was applied to Biochemistry instruction of Nursing and Clinical Medicine majors. The students' academic performance and perceptions of self-cognition were used to assess the blended Biochemistry classroom. Students who participated in the blended classroom model achieved higher academic performance (p < 0.01) and reported a significant improvement in their perceptions of self-cognition (p < 0.05) compared to the control group. Moreover, the effectiveness of the blended Biochemistry classroom on the small size class (Nursing major) was stronger than on the large size class (Clinical Medicine major).

Targeting the lysosome by an aminomethylated Riccardin D triggers DNA damage through cathepsin B-mediated degradation of BRCA1.

RD-N, an aminomethylated derivative of riccardin D, is a lysosomotropic agent that can trigger lysosomal membrane permeabilization followed by cathepsin B (CTSB)-dependent apoptosis in prostate cancer (PCa) cells, but the underlying mechanisms remain unknown. Here we show that RD-N treatment drives CTSB translocation from the lysosomes to the nucleus where it promotes DNA damage by suppression of the breast cancer 1 protein (BRCA1). Inhibition of CTSB activity with its specific inhibitors, or by CTSB-targeting siRNA or CTSB with enzyme-negative domain attenuated activation of BRCA1 and DNA damage induced by RD-N. Conversely, CTSB overexpression resulted in inhibition of BRCA1 and sensitized PCa cells to RD-N-induced cell death. Furthermore, RD-N-induced cell death was exacerbated in BRCA1-deficient cancer cells. We also demonstrated that CTSB/BRCA1-dependent DNA damage was critical for RD-N, but not for etoposide, reinforcing the importance of CTSB/BRCA1 in RD-N-mediated cell death. In addition, RD-N synergistically increased cell sensitivity to cisplatin, and this effect was more evidenced in BRCA1-deficient cancer cells. This study reveals a novel molecular mechanism that RD-N promotes CTSB-dependent DNA damage by the suppression of BRCA1 in PCa cells, leading to the identification of a potential compound that target lysosomes for cancer treatment.

Pro-metastatic activity of AGR2 interrupts angiogenesis target bevacizumab efficiency via direct interaction with VEGFA and activation of NF-κB pathway.

Anterior gradient 2 (AGR2), an endoplasmic reticulum (ER)-resident protein-disulfide isomerase (PDI), is associated with cancer development and malignant progression. Here, we show that high level of AGR2 promotes the aggressive phenotype of prostate cancer (PCa) mouse models developed by either patient-derived xenografts or surgical intra-prostate implantation of PCa cells, associated with enrichment of the blood vessel network in tumor tissues. Angiogenesis markers VEGFR2 and CD34, accompanied with the invasive marker Vimentin, were predominantly stained in metastatic liver tissues. Secreted AGR2 was defined to enhance VEGFR2 activity as evidenced by physical interaction of purified recombinant human AGR2 (rhAGR2) with rhVEGFA through the formation of a disulfide bond. Mutant or deleted thioredoxin motif in rhAGR2 was also unable to bind to rhVEGFA that led to the significant abolishment in the vessel formation, but partially affecting the aggressive process, implicating alternative mechanisms are required for AGR2-conferring metastasis. Cytosolic AGR2 contributed to cell metastasis ascribed to its stabilizing effect on p65 protein, which subsequently activated the NF-κB and facilitated epithelial to mesenchymal transition (EMT). Importantly, GSH and cabozantinib, but not bevacizumab, effectively blocked the pro-angiogenic effect of rhAGR2 in vitro and in vivo, providing evidence that secreted AGR2 acts as a predictive biomarker for selection of angiogenesis-targeting therapeutic drugs based on its levels in the circular system.

Downregulation of reticulocalbin-1 differentially facilitates apoptosis and necroptosis in human prostate cancer cells.

Reticulocalbin 1 (RCN1), an endoplasmic reticulum (ER)-resident Ca2+ -binding protein, is dysregulated in cancers, but its pathophysiological roles are largely unclear. Here, we demonstrate that RCN1 is overexpressed in clinical prostate cancer (PCa) samples, associated with cyclin B, not cyclin D1 expression, compared to that of benign tissues in a Chinese Han population. Downregulation of endogenous RCN1 significantly suppresses PCa cell viability and arrests the cell cycles of DU145 and LNCaP cells at the S and G2/M phases, respectively. RCN1 depletion causes ER stress, which is evidenced by induction of GRP78, activation of PERK and phosphorylation of eIF2α in PCa cells. Remarkably, RCN1 loss triggers DU145 cell apoptosis in a caspase-dependent manner but mainly causes necroptosis in LNCaP cells. An animal-based analysis confirms that RCN1 depletion suppresses cell proliferation and promotes cell death. Further investigations reveal that RCN1 depletion leads to elevation of phosphatase and tensin homolog (PTEN) and inactivation of AKT in DU145 cells. Silencing of PTEN partially restores apoptotic cells upon RCN1 loss. In LNCaP cells, predominant activation of CaMKII is important for necroptosis in response to RCN1 depletion. Thus, RCN1 may promote cell survival and serve as a useful target for cancer therapy.

Hyper-acetylation contributes to the sensitivity of chemo-resistant prostate cancer cells to histone deacetylase inhibitor Trichostatin A.

Therapeutic agents are urgently needed for treating metastatic castration-refractory prostate cancer (mCRPC) that is unresponsive to androgen deprivation and chemotherapy. Our screening assays demonstrated that chemotherapy-resistant prostate cancer (PCa) cells are more sensitive to HDAC inhibitors than paired sensitive PCa cells, as demonstrated by cell proliferation and apoptosis in vitro and in vivo. Kinetic study revealed that TSA-induced apoptosis was significantly dependent on enhanced transcription and protein synthesis in an early stage, which subsequently caused ER stress and apoptosis. ChIP analysis indicated that TSA increased H4K16 acetylation, promoting ER stress gene transcription. The changes in Ac-H4K16, ATF3 and ATF4 were also validated in TSA-treated animals. Further study revealed the higher enzyme activity of HDACs and an increase in acetylated proteins in resistant cells. The higher nucleocytoplasmic acetyl-CoA in resistant cells was responsible for elevated acetylation status of protein and a more vigorous growth state. These results strongly support the pre-clinical application of HDAC inhibitors for treating chemotherapy-resistant mCRPC.

Oxidative stress induced autophagy in cancer associated fibroblast enhances proliferation and metabolism of colorectal cancer cells.

Tumors are comprised of malignant cancer cells and stromal cells which constitute the tumor microenvironment (TME). Previous studies have shown that cancer associated fibroblast (CAF) in TME is an important promoter of tumor initiation and progression. However, the underlying molecular mechanisms by which CAFs influence the growth of colorectal cancer cells (CRCs) have not been clearly elucidated. In this study, by using a non-contact co-culture system between human colorectal fibroblasts (CCD-18-co) and CRCs (LoVo, SW480, and SW620), we found that fibroblasts existing in tumor microenvironment positively influenced the metabolism of colorectal cancer cells, through its autophagy and oxidative stress pathway which were initially induced by neighboring tumor cells. Therefore, our data provided a novel possibility to develop fibroblasts as a potential target to treat CRC.

Intravenous high mobility group box 1 upregulates the expression of HIF-1α in the myocardium via a protein kinase B-dependent pathway in rats following acute myocardial ischemia.

The effects of intravenous high mobility group box 1 (HMGB1) on myocardial ischemia/reperfusion (I/R) injury remains to be elucidated. The purpose of the present study was to investigate the effects of intravenous HMGB1 on the expression of hypoxia inducible factor-1α (HIF-1α) in the myocardium of rats following acute myocardial ischemia, and to examine the effects of intravenous HMGB1 on myocardial I/R injury. Male Wistar rats were divided into the following groups: Sham operation group (n=10), a group exposed to ischemia for 30 min and reperfusion for 4 h (I/R group) as a control (n=10), an HMGB group, in which 100 ng/kg HMGB was administered intravenously 30 min prior to ischemia (n=10), an LY group, in which LY294002, an inhibitor of phosphoinositide 3-kinase (PI3K), was administered intravenously (0.3 mg/kg) 40 min prior to ischemia (n=10), and the HMGB1+LY group, in which HMGB1 (100 ng/kg) and LY294002 (0.3 mg/kg) were administered intravenously 30 min and 40 min prior to ischemia, respectively (n=10). The serum levels of cardiac troponin I (cTnI) and tumor necrosis factor-α (TNF-α), and myocardial infarct size were measured. The expression levels of phosphorylated Akt and HIF-1α were investigated using western blot analyses. The results showed that pre-treatment with HMGB1 significantly decreased serum levels of cTnI, and TNF-α, and reduced myocardial infarct size following 4 h reperfusion (all P<0.05). HMGB1 also increased the expression levels of HIF-1α and p-Akt induced by I/R (P<0.05). LY294002 was found to eliminate the effects of intravenous HMGB1 on myocardial I/R injury (P<0.05). These results suggest that intravenous pre-treatment with HMGB1 may exert its cardioprotective effects via the upregulation of the myocardial expression of HIF-1α, which may be regulated by the PI3K/Akt signaling pathway, in rats following acute myocardial I/R.

Metformin prevents DMH-induced colorectal cancer in diabetic rats by reversing the warburg effect.

Epidemiologic studies have shown that the treatment of diabetics with metformin reduced the risk of cancer-related mortality. Here, we investigated the chemopreventive effects of metformin on dimethylhydrazine (DMH)-induced colorectal carcinogenesis in diabetic SD rats following metformin treatment and the effect on Warburg effect involved in this process. Diabetic rat models were induced with high-fat feeding in combination with a low dose of Streptozotocin (STZ) and then induce colorectal cancer with a low dose of DMH. The formation of colorectal Aberrant crypt foci (ACF) and the incidence, number and size of the tumor were measured. The proliferation indices of colonic tissues were determined through Proliferating cell nuclear antigen (PCNA) immunostaining. Then detect the expression of PK and IDH in colonic tissues using immunohistochemistry and Western blot. The enzyme activities of HK and PDH in colonic tissues were measured. The growth and expression of PK and IDH and activity of HK and PDH in cell lines LoVo and HT-29 were measured after metformin treatment. The results showed that metformin treatment significantly inhibited the formation of ACF and tumors. The proliferation index of colonic tissues was significantly decreased following metformin treatment. In addition, metformin inhibited cell growth and decreased the imbalance in the expression of the enzymes involved in glycolysis and the TCA cycle. These findings suggested that metformin might produce a synergistic colon cancer-preventative effect in diabetic patients through the regulation of the enzymes expression involved in glucose metabolism.

Postconditioning with simvastatin decreases myocardial injury in rats following acute myocardial ischemia.

The aim of the present study was to investigate whether postconditioning with simvastatin attenuated myocardial ischemia reperfusion injury by inhibiting the expression of high mobility group box 1 (HMGB1) in rat myocardium following acute myocardial ischemia. In total, 30 male Sprague-Dawley rats were divided into sham operation (sham; n=10), acute myocardial infarction (AMI; n=10) and simvastatin (sim; n=10) groups. The AMI and sim groups were subjected to ischemia for 30 min, followed by reperfusion for 180 min. The rats in the sim group were administered 20 mg/kg simvastatin intravenously 5 min prior to reperfusion. Subsequently, the infarct size, serum cardiac troponin (c-TnI), tumor necrosis factor (TNF)-α and myocardial malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were measured. Western blot analysis was used to detect the protein expression of HMGB1. Postconditioning with simvastatin was shown to decrease the infarct size and HMGB1 expression levels in the myocardium following AMI (P<0.05). In addition, postconditioning with simvastatin not only decreased the serum levels of c-TnI and TNF-α (P<0.05), but also inhibited the increase in MDA levels and the reduction in SOD activity (P<0.05). Therefore, postconditioning with simvastatin was shown to attenuate myocardial injury. The underlying mechanism may be associated with the downregulation of HMGB1 expression in the ischemic myocardium.

Diabetes promotes DMH-induced colorectal cancer by increasing the activity of glycolytic enzymes in rats.

The objective of the present study was to investigate the association between diabetes mellitus and colorectal carcinogenesis as well as the possible mechanism involved in this interaction. Diabetes rat models were induced with a low dose of STZ followed by a low dose of DMH to induce colorectal cancer. The formation of ACF in the colon and the incidence, number and size of tumors were measured. The activity of glycolytic enzymes in colonic tissues was also measured. The results demonstrated that both the total number of ACF and the number of foci that contain a different number of crypts were increased in diabetic rats. At the end of the experimental treatment, the incidence, number and size of tumors were also increased in diabetic rats. Overall, these data indicated that diabetes increased the risk of colorectal cancer. The activity of HK and PK in colonic tissues was increased in diabetic rats, whereas the activity of PDH was decreased. In addition, the activities of these enzymes in intratumor were higher than that of in peritumor. These data indicated that the high rate of glycolysis may play a role in colorectal carcinogenesis in diabetic rats.

In vitro properties of apheresis platelet during extended storage in plasma treated with anandamide.

BACKGROUND: In China apheresis platelets (PLTs) are stored in plasma for only 5 days, resulting in PLT inventory pressures. Anandamide (ANA) was reported to be a potential agent to inhibit PLT apoptosis. The aim of this study was to evaluate the characteristics of extended storage PLTs in plasma treated with ANA in vitro. METHODS: Apheresis PLTs (n = 20) were prepared in plasma treated with ANA, and stored at 22 °C for up to 11 days. On day 1, 3, 5, 7, 9 and 11, PLTs were tested for PLT count, mean PLT volume (MPV), PLT distribution width (PDW), pH, pCO(2), pO(2), hypotonic shock response (HSR), phosphatidylserine (PS) exposure and soluble P-selectin content. RESULTS: PLTs stored in plasma with/without ANA didn't show significant differences during the first 5 days of storage. From the 7(th) day on, PLTs stored in plasma with ANA displayed significantly lower PS expression, soluble P-selectin content and higher HSR scores than those stored in plasma without ANA (P <0.05), respectively. CONCLUSION: The extended storage of PLTs in plasma treated with 0.5 µmol/l ANA showed better characteristics of the PLTs, compared with the control group, which was suggested to potentially alleviate the PLT storage lesion.

Regulation of SOD2 and ß-arrestin1 by interleukin-6 contributes to the increase of IGF-1R expression in docetaxel resistant prostate cancer cells.

Although several mechanisms behind resistance to docetaxel in castration-refractory prostate cancer (CRPC) have been investigated, molecular determinants of evolved resistance are still not entirely understood. Proteomics-based analysis in this study revealed that SOD2, associated with downregulation of reactive oxygen species (ROS), was significantly up-regulated in docetaxel-resistant (PC3/Doc) cells if compared to sensitive cells, and the expression of redox-regulated genes such as IGF-1R, CXCR4, and BCL2 was increased as well. Forced expression of SOD2 in sensitive cells led to the increase of IGF-1R and association with drug resistance, whereas silencing of SOD2 resulted in the decrease of IGF-1R at the protein level in resistant cells. Further study revealed that SOD2 acted as a negative regulator of ß-arrestin1 that is an important adaptor responsible for degradation of IGF-1R via the changes in ROS, as evidenced by observations that an antioxidant agent substantially attenuated ß-arrestin1 expression in vitro and in vivo. Finally, we found that blocking of IL6 that was up-regulated in resistant cells resulted in attenuation of SOD2 and STAT3, and simultaneously in increased expression of ß-arrestin1. The modulation consequently led to the decreased IGF-1R at both protein and transcription levels. Together, our data provide a novel explanation that high level of IL6 stimulated SOD2 expression that, at least partially, contributed to the low level of ROS that would likely result in a sustained increase in the expression of IGF-1R through abolishment of ß-arrestin1 in docetaxel resistant cells.

Anti-inflammatory effect of Marchantin M contributes to sensitization of prostate cancer cells to docetaxel.

As pro-inflammatory cytokines and chemokines contribute to the malignancy of many types of human cancer, we examined the anti-inflammatory effect of bisbibenzyls, a diverse bioactive group of naturally occurring compounds. Marchantin M (Mar M) was identified through a screening process of these compounds as a potent anti-inflammatory agent based on its capacity to inhibit LPS-induced IL6, IL1ß and CCL2 expression in HUVECs and PBMCs without affecting cell proliferation. Since Mar M has been found to exhibit anticancer activity, we observed that Mar M treatment also resulted in decreases in the expressions of IL6, IL1ß and TNFα in metastatic prostate cancer (PCa) cells. This effect was further confirmed in other cancer cell lines that express high level of pro-inflammatory cytokines. Furthermore, inactivation of NF-κB, a critical transcription factor controlling many pro-inflammatory cytokine expressions, was observed in Mar M-treated PCa cells as evidenced by decreased phosphor-p65 and subsequently phosphor-STAT3. Mar M also suppressed phosphorylation of IKBα, an inhibitor of NF-κB in the cytosol. However, reduced phosphor-p65 by Mar M was slightly increased when knockdown of IKBα, suggesting that Mar M may target upstream molecules of IKBα/NF-κB signaling. Finally, treatment with Mar M resulted in more enhanced-sensitivity of PCa cells to docetaxel-induced apoptosis than that of the IL6 blocking. Our study demonstrates the potential of the anti-inflammatory agent Mar M as an adjuvant to improve the efficacy of traditional anticancer agents such as docetaxel.

Induction of DNA damage and p21-dependent senescence by Riccardin D is a novel mechanism contributing to its growth suppression in prostate cancer cells in vitro and in vivo.

PURPOSE: Our previous studies had shown that Riccardin D (RD) exhibited cytotoxic effects by induction of apoptosis and inhibition of angiogenesis and topoisomerase II. Here, we reported that apoptosis is not the sole mechanism by which RD inhibits tumor cell growth because low concentrations of RD caused cellular senescence in prostate cancer (PCa) cells. METHODS: Low concentrations of RD were used to treat PCa cells in vitro and in vivo, and senescence-associated ß-galactosidase activity, DNA damage response markers, and/or colony-forming ability, cell cycle were analyzed, respectively. We then used siRNA knockdown to identify key factor in RD-triggered cellular senescence. RESULTS: RD treatment caused growth arrest at G0/G1 phase with features of cellular senescence phenotype such as enlarged and flattened morphology, increased senescence-associated-beta-galactosidase staining cells, and decreased cell proliferation in PCa cells. Induction of cellular senescence by RD occurred through activation of DNA damage response including increases in the phosphor-H2AX, inactivation of Chk1/2, and suppression of repair-related Ku70/86 and phosphor-BRCA1 in PCa cells in vitro and in vivo. Analysis of expression levels of p53, p21(CIP1), p16(INK4a), p27(KIP1), pRb and E2F1 and genetic knockdown of p21(CIP1) demonstrated an important role of p21(CIP1) in RD-triggered cellular senescence. CONCLUSIONS: Involvement of the DNA damage response and p21(CIP1) defines a novel mechanism of RD action and indicates that RD could be further developed as a promising anticancer agent for cancer therapy.

Riccardin D Exerts Its Antitumor Activity by Inducing DNA Damage in PC-3 Prostate Cancer Cells In Vitro and In Vivo.

We recently reported that Riccardin D (RD) was able to induce apoptosis by targeting Topo II. Here, we found that RD induced cell cycle arrest in G2/M phase in PC-3 cells, and caused remarkable DNA damage as evidenced by induction of γH2AX foci, micronuclei, and DNA fragmentation in Comet assay. Time kinetic and dose-dependent studies showed that ATM/Chk2 and ATR/Chk1 signaling pathways were sequentially activated in response to RD. Blockage of ATM/ATR signaling led to the attenuation of RD-induced γH2AX, and to the partial recovery of cell proliferation. Furthermore, RD exposure resulted in the inactivation of BRCA1, suppression of HR and NHEJ repair activity, and downregulation of the expressions and DNA-end binding activities of Ku70/86. Consistent with the observations, microarray data displayed that RD triggered the changes in genes responsible for cell proliferation, cell cycle, DNA damage and repair, and apoptosis. Administration of RD to xenograft mice reduced tumor growth, and coordinately caused alterations in the expression of genes involved in DNA damage and repair, along with cell apoptosis. Thus, this finding identified a novel mechanism by which RD affects DNA repair and acts as a DNA damage agent in prostate cancer.

Acidic amino acids increase fusion activity in the specific fusion domain of Newcastle disease virus fusion protein.

To explore the effects of amino acids Gln and Asn within the specific fusion domain of fusion (F) protein on the specific membrane fusion in Newcastle disease virus (NDV), the mutants Q204E-Q205E and N245D were constructed in the specific fusion domain of F protein. The mutant genes were co-expressed with homologous or heterologous hemagglutinin-neuraminidase (HN) in BHK21 cells. Cell fusion functions of mutants were analyzed with Giemsa staining and reporter gene methods. Cell surface expression efficiency was analyzed with immunofluorescence assay and fluorescence-activated cell sorter analysis. Co-immunoprecipitation was performed to analyze the interaction of mutant F proteins with the homotypic HN protein. Both Q204E-Q205E and N245D mutations caused increased cell-cell fusion activity when they were co-expressed with homotypic HN protein. The mutant F proteins had slight changes in cell surface expression compared with that of wild-type F protein. The interactions of Q204E-Q205E or N245D with their homotypic HN increased significantly (P < 0.01) compared with the wild-type F protein. Neither Q204-Q205E nor N245D caused cell fusion in the presence of heterologous HN protein. Our data suggested that the residues Q204, Q205, and N245 play a critical role in the regulation of cell fusion. They may decrease the interaction of wild-type NDV F and NDV HN to suppress the fusion activity for survival of the infected host, which may enable a persistent virus infection and long-term virus reproduction and spread.

Retigeric acid B-induced mitophagy by oxidative stress attenuates cell death against prostate cancer cells in vitro.

AIM: Retigeric acid B (RAB), a pentacyclic triterpenic acid from Lobaria kurokawae Yoshim, has been found to induce apoptosis in prostate cancer cells. The aim of this study was to investigate the roles of mitochondrial damage-caused mitophagy in RAB-induced prostate cancer cell death in vitro. METHODS: Human prostate cancer PC3 and LNCaP cells were tested. Cell viability was analyzed with MTT assay. Cell apoptosis, ROS level and mitochondrial transmembrane potential (mtΔψ) were measured with flow cytometry. Autophagy- and apoptosis-related proteins were studied using Western blotting. GFP-LC3B puncta, mitochondrial swelling and mitophagy were examined morphologically. Quantitative RT-PCR was used to measure LC3B mRNA level, and siRNA was used to knock down LC3BII. RESULTS: In both PC3 and LNCaP cells, RAB (15 µmol/L) increased ROS accumulation and decreased mtΔψ in a time-dependent manner. Furthermore, RAB induced mitochondrial swelling and mitophagy, significantly increased LC3B expression and conversion of LC3BI to LC3BII, and the elimination of mitochondria by LC3BII-containing autophagolysosomes. In addition, RAB suppressed the PI3K/Akt/mTOR pathway activation. Pretreatment of PC3 cells with autophagy inhibitor 3-MA (5 mmol/L) or the lysosomal protease inhibitor CQ (10 µmol/L) significantly increased RAB-induced apoptosis. Similar results were obtained in RAB-treated PC3 cells with LC3B knocked down. CONCLUSION: RAB induces mitochondrial damage and mitophagy that attenuates RAB-induced prostate cancer cell death. Thus, suppression of mitophagy might be a potential strategy for improving the chemotherapeutic effects of RAB.

Human leukocyte antigen-C and killer cell immunoglobulin-like receptor gene polymorphisms among patients with syphilis in a Chinese Han population.

Syphilis is a sexually transmitted infection caused by the Treponema pallidum subspecies pallidum spirochete bacterium. The killer cell immunoglobulin-like receptors (KIR), interacting with human leukocyte antigens (HLA), regulate the activations of natural killer (NK) cells and certain T-cell subsets in response to microbe infection. The objective of this study was to explore whether KIR and HLA-C gene polymorphisms were associated with syphilis in a Chinese Han population. Polymerase chain reaction with sequence-specific primers (PCR-SSP) method was used to genotype KIR and HLA-C genes in 231 syphilis patients and 247 healthy controls. Framework genes KIR2DL4, KIR3DL2, KIR3DL3 and KIR3DP1 were present in all individuals. The frequencies of KIR2DS3 and KIR3DS1 were higher in syphilis patients than in healthy controls (p = 0.030 and p = 0.038, respectively), while the frequency of KIR2DS5 was higher in healthy controls than in syphilis patients (p = 0.015; OR = 0.575). The homozygote for HLA-C1 allele (HLA-C1C1) was more common in controls compared with syphilis patients (p = 0.030; OR = 0.667). The frequency of individuals with HLA-C1C1 and KIR2DL3 genotype was higher in control group relative to syphilis patient group (p = 0.018; OR = 0.647). These data indicated that KIR2DS3 and KIR3DS1 were more prevalent in syphilis patients than in controls, and that KIR2DS5, HLA-C1C1 and HLA-C1C1-KIR2DL3 were more prevalent in controls than in syphilis patients, respectively. These will require further investigation using functional studies.

Oridonin nanosuspension was more effective than free oridonin on G2/M cell cycle arrest and apoptosis in the human pancreatic cancer PANC-1 cell line.

Oridonin, a diterpenoid isolated from Rabdosia rubescencs, has been reported to have antitumor effects. However, low solubility has limited its clinical applications. Preparation of drugs in the form of nanosuspensions is an extensively utilized protocol. In this study, we investigated the anticancer activity of oridonin and oridonin nanosuspension on human pancreatic carcinoma PANC-1 cells. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to investigate the effect of oridonin on cell growth. Propidium iodide and Hoechst 33342 staining were used to detect morphologic changes. The percentage of apoptosis and cell cycle progression was determined by flow cytometric method staining with propidium iodide. Annexin V-fluorescein isothiocyanate (FITC)/PI staining was used to evaluate cell apoptosis by flow cytometry. Caspase-3 activity was measured by spectrophotometry. The apoptotic and cell cycle protein expression were determined by Western blot analysis. Both oridonin and oridonin nanosuspension induced apoptosis and G(2)/M phase cell cycle arrest, and the latter had a more significant cytotoxic effect. The ratio of Bcl-2/Bax protein expression was decreased and caspase- 3 activity was stimulated. The expression of cyclin B1 and p-cdc2 (T161) was suppressed. Our results showed that oridonin nanosuspension was more effective than free oridonin on G(2)/M cell cycle arrest and apoptosis in the human pancreatic cancer PANC-1 cell line.