Effect of remote ischemic preconditioning intervention on serum levels of microRNA-582-5p/HMGB1 in patients with acute cerebral infarction.

OBJECTIVE: Acute cerebral infarction (ACI) contributes to disability and death accross the globe. Remote ischemic preconditioning (RIPC) reduces cerebral infarct size and improves neurological function in ACI. We conducted this research to reveal the effects of RIPC intervention on serum levels of microRNA-582-5p (miR-582-5p)/high mobility group box-1 protein (HMGB1), inflammation, oxidative stress and neurological function in patients with ACI. METHODS: In this study, 158 patients with ACI were prospectively selected and randomized into the control (administered symptomatic medication alone) and the RIPC (underwent RIPC of the limbs based on medication) groups, with their clinical baseline data documented. Serum levels of miR-582-5p, and HMGB1 and inflammatory factors [tumor necrosis factor alpha (TNF-α)/interleukin-1beta (IL-1ß)/IL-10] were assessed by RT-qPCR/ELISA, followed by comparisons of oxidative stress indices [glutathione-peroxidase (GSH-Px)/catalase (CAT)/superoxide dismutase (SOD)] using a fully automatic biochemical analyzer. Correlations between serum miR-582-5p with serum HMGB1, and between their levels with TNF-α/IL-1ß/IL-10 were analyzed by Pearson analysis. The NIHSS score/Barthel Index scale were used to assess neurological function/daily living ability. Intervention safety for ACI patients was evaluated. RESULTS: RIPC intervention increased serum miR-582-5p levels and decreased serum HMGB1 levels in ACI patients. RIPC intervention significantly reduced inflammation (diminished TNF-α/IL-1ß levels, increased IL-10 level) and oxidative stress (elevated GSH-Px/CAT/SOD levels) in ACI patients. Serum miR-582-5p was negatively correlated with TNF-α and IL-1ß levels, while positively correlated with IL-10 level, while HMGB1 was positively correlated with TNF-α and IL-1ß levels, while negatively correlated with IL-10 level. miR-582-5p was negatively correlated with HMGB1. RIPC intervention improved neurological function (reduced NIHSS, increased Barthel scores) in ACI patients to some extent. RIPC had certain effectiveness and safety in the treatment of ACI. CONCLUSION: After RIPC intervention, serum miR-582-5p levels were increased, HMGB1 levels were decreased, and inflammation and oxidative stress were reduced in ACI patients, which mitigated neurological deficits, improved patients' ability to perform life activities, and exerted neuroprotective effects to some extent.

Correction: Hao et al. Processing Aspectual Agreement in a Language with Limited Morphological Inflection by Second Language Learners: An ERP Study of Mandarin Chinese. Brain Sci. 2022, 12, 524.

In the published publication [...].

Exosome-shuttled MYCBPAP from bone marrow mesenchymal stem cells regulates synaptic remodeling and ameliorates ischemic stroke in rats.

BACKGROUND AND PURPOSE: Mesenchymal stem cells (MSC) have been demonstrated to improve cardiac function via the secretion of paracrine factors rather than direct differentiation. We, therefore, investigated whether bone marrow-derived MSC (BMSC)-released exosomes (BMSC-exo) enhance neurological recovery in spontaneously hypertensive rats (SHR) with ischemic stroke. METHODS: Markers of BMSC and BMSC-exo were detected to characterize BMSC and BMSC-exo. A green fluorescent PKH-67-labeled assay was conducted to ensure BMSC-exo internalization. Rat neuronal cells (RNC) were induced with Ang II and oxygen-glucose deprivation. The protective effects of BMSC-exo on RNC were studied by CCK-8, LDH, and immunofluorescence assays. SHR were subjected to middle cerebral artery occlusion, and the systolic and diastolic blood pressure changes in the modeled rats were measured. The effects of BMSC-exo on SHR were investigated by mNSS scoring, foot-fault tests, immunohistochemistry, Western blot, TTC staining, TUNEL, and HE staining. The hub genes related to SHR and proteins shuttled by BMSC-exo were intersected to obtain a possible candidate, followed by rescue experiments. RESULTS: BMSC-exo significantly promoted RNC viability and repressed cell apoptosis and cytotoxicity. Moreover, SHR administrated with BMSC-exo exhibited significant improvement in functional recovery and narrowed infarct size. BMSC-exo shuttled the MYCBPAP protein. Knockdown of MYCBPAP inhibited the protective effects of BMSC-exo on RNC and exacerbated synaptic damage in SHR. CONCLUSIONS: MYCBPAP shuttled by BMSC-exo facilitates synaptic remodeling in SHR, which may contribute to a therapeutic strategy for ischemic stroke treatment.

Neuroprotective mechanism of crocin via PI3K/Akt/mTOR signaling pathway after cerebral infarction: an in vitro study.

OBJECTIVES: To explore the potential neuroprotective mechanism of crocin after cerebral infarction. METHODS: The murine hippocampal neuronal cell line HT-22, was used as the study model, with a control group, OGD-group, low-dose crocin group, middle-dose crocin group, and high-dose crocin group. Except for the control-group, cells in the other groups were treated with OGD for 6 h, in which 1 µg/mL, 2 µg/mL and 5 µg/mL of crocin were added in low-dose group, medium-dose group and high-dose group, respectively. Subsequently, the OGD cells were cultured for another 6 h. CCK-8 assay was carried out to detect the cell viability of each group, flow cytometry was used to detect cell apoptosis, immunofluorescence was conducted to detect the expression of reactive oxygen species, and Western Blot was performed to detect the protein expression of p-PI3K, p-Akt, p-mTOR, LC-3 I, LC-3 II, and Beclin-1. RESULTS: After hypoxia-reoxygenation treatment, the viability of HT22 cells was remarkably decreased, the apoptosis rate and expression of ROS were significantly increased, the protein expression of p-PI3K, p-Akt and p-mTOR were reduced, while the expression of LC-3 II/I and Beclin-1 were increased. After crocin treatment, the activity of hypoxic reoxygenated cells increased, the apoptosis rate decreased, the expression of reactive oxygen species dropped, the protein expression of p-PI3K, p-Akt and p-mTOR increased, and the expression of LC-3 II/I and Beclin-1 decreased. CONCLUSION: At the cellular level, crocin can inhibit autophagy by activating the PI3K/Akt/mTOR pathway, and reduce the level of oxidative stress, thus playing a neuroprotective role.

Processing Aspectual Agreement in a Language with Limited Morphological Inflection by Second Language Learners: An ERP Study of Mandarin Chinese.

Previous studies on the neural cognitive mechanisms of aspectual processing in second language (L2) learners have focused on Indo-European languages with rich inflectional morphology. These languages have aspects which are equipped with inflected verb forms combined with auxiliary or modal verbs. Meanwhile, little attention has been paid to Mandarin Chinese, which has limited morphological inflection, and its aspect is equipped with aspectual particles (e.g., le, zhe, guo). The present study explores the neurocognitive mechanism of Mandarin Chinese aspect processing among two groups of late Mandarin Chinese proficient learners with Thai (with Mandarin Chinese-like aspect markers) and Indonesian (lack of Mandarin Chinese-like aspect markers) as their first language (L1). We measured event-related potentials (ERPs) time locked to the aspect marker le in two different conditions (the aspect violation sentences and the correct sentences). A triphasic ELAN-LAN-P600 effect was produced by the Mandarin Chinese native speakers. However, there was no ELAN and LAN in Indonesian native speakers and Thai native speakers, except a 300-500 ms negativity widely distributed in the right hemisphere and P600-like effect. This suggests that both groups of Mandarin Chinese learners cannot reach the same level as Mandarin Chinese native speakers to process Mandarin Chinese aspect information, probably due to the complex feature of Mandarin Chinese aspect maker, the participants' L2 proficiency and age of L2 acquisition.

MiR-485-3p modulates neural stem cell differentiation and proliferation via regulating TRIP6 expression.

Recent references have showed crucial roles of several miRNAs in neural stem cell differentiation and proliferation. However, the expression and role of miR-485-3p remains unknown. In our reference, we indicated that miR-485-3p expression was down-regulated during NSCs differentiation to neural and astrocytes cell. In addition, the TRIP6 expression was up-regulated during NSCs differentiation to neural and astrocytes cell. We carried out the dual-luciferase reporter and found that overexpression of miR-485-3p decreased the luciferase activity of pmirGLO-TRIP6-wt but not the pmirGLO-TRIP6-mut. Ectopic expression of miR-485-3p decreased the expression of TRIP6 in NSC. Ectopic miR-485-3p expression suppressed the cell growth of NSCs and inhibited nestin expression of NSCs. Moreover, elevated expression of miR-485-3p decreased the ki-67 and cyclin D1 expression in NSCs. Furthermore, we indicated that miR-485-3p reduced proliferation and induced differentiation of NSCs via targeting TRIP6 expression. These data suggested that a crucial role of miR-485-3p in self-proliferation and differentiation of NSCs. Thus, altering miR-485-3p and TRIP6 modulation may be one promising therapy for treating with neurodegenerative and neurogenesis diseases.

Effects of Vitamin K3 Combined with UVB on the Proliferation and Apoptosis of Cutaneous Squamous Cell Carcinoma A431 Cells.

PURPOSE: Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer and its incidence continues to rise yearly. Photodynamic therapy (PDT) is a non-invasive form of cancer therapy, which utilizes the combined action of a photosensitizer, light, and oxygen molecules to selectively cause cellular damage to tumor cells. Vitamin K3 (VitK3) has been shown to induce apoptosis and inhibit the growth of tumor cells in humans. The purpose of this study was to determine the effect of VitK3 and ultraviolet radiation B (UVB) on oxidative damage, proliferation and apoptosis of A431 cells. METHODS: CCK-8 assay was used to detect cell proliferation; Hoechst staining, TUNEL assay and flow cytometry analysis were used to detect apoptosis. Western Blot was perfomed to measure the expression of apoptosis-related proteins. Flow cytometry analysis was employed to detect the reactive oxygen species (ROS) levels and mitochondrial membrane potential. Finally, the role of VitK3 in combination with UVB on the proliferation and apoptosis of A431 cells was investigated using mice xenograft models. RESULTS: We found that the co-treatment of VitK3 combined with UVB more significantly inhibited the growth and proliferation of A431 cells than either VitK3 or UVB alone. Hoechst 33258 staining and flow cytometry analysis revealed that apoptosis was more pronounced in the VitK3-UVB group compared to the VitK3 and UVB groups. Moreover, flow cytometry analysis showed that ROS and the depolarization of the mitochondrial membrane potential were higher in all the co-treatment groups compared to the control, VitK3, and UVB groups. The VitK3-UVB group exhibited a significantly lower tumor growth rate in mouse xenograft models. CONCLUSION: This study reveals that VitK3 combined with UVB inhibits the growth and induces apoptosis of A431 cells in vitro and suppresses tumor growth and promotes apoptosis of cSCC in vivo.

Meta-analysis of the effects of anti-epidermal growth factor receptor on recurrent/metastatic head and neck squamous cell carcinoma.

BACKGROUND: We performed a meta-analysis to compare the efficacy and safety of anti-epidermal growth factor receptor (EGFR) therapy and non-anti-EGFR therapy in recurrent/metastatic (RM) head and neck squamous cell carcinoma (HNSCC). METHODS: The Cochrane library, WanFang Data, PubMed, Medline, VIP, CBM, and EBSCO databases were searched for relevant studies. The objective response rate (ORR, defined as complete response or partial response according to RECTST version 1.1) and grade 3 to 4 adverse effects were used. RESULTS: Ten studies involving 2260 patients were included. Primary meta-analysis showed that anti-EGFR therapy improved the ORR [odds ratio (OR): 1.79, 95% confidence interval 1.44-2.21, P <.00001]. Subgroup analyses revealed that the ORR of patients with RM HNSCC could be improved by monoclonal antibodies (OR: 1.89, 1.46-2.45, P <.00001) and tyrosine kinase inhibitors (OR: 1.57, 1.07-2.31, P = .02). Analysis of grade 3 to 4 adverse effects demonstrated that diarrhea (3.15, [1.90, 5.20]), rash/desquamation (13.66, [6.86, 27.20]), hypomagnesemia (1.83, [1.28, 2.62]), vomiting (1.99, [1.00, 3.95]), anorexia (3.34, [1.45, 7.73]), dehydration (2.22, [1.19, 4.12]), and hypokalemia (1.63, [1.09, 2.42]) were significantly associated with anti-EGFR therapy. CONCLUSION: Anti-EGFR therapy is recommended for patients with RM HNSCC. Adverse effects, such as diarrhea, anorexia, hypomagnesemia, and hypokalemia, should be carefully monitored during anti-EGFR therapy.

PTPN21 protects PC12 cell against oxygen-glucose deprivation by activating cdk5 through ERK1/2 signaling pathway.

PTPN21, a cytosolic non-receptor tyrosine phosphatase isolated from human skeletal muscle, was reported to promote neuronal survival. Nevertheless, it is not clear whether PTPN21 plays a role in hypoxia ischemia-induced neuronal injury. A proper understanding of the PTPN21 mechanism in neuron growth regulation is limited. In this study, we investigated the neuroprotective effects and potential mechanism of PTPN21 on oxygen glucose deprivation (OGD)-injured PC12 cells. The ischemic stroke model of PC12 cells was made by OGD for 2h, after transfection of the PTPN21 siRNA and pcDNA 3.1 PTPN21(+). Cell viability was tested using the MTT and CCK-8 assay. Apoptotic cells were estimated by Annexin V-FITC/PI staining and caspase-3 activity using the Caspase-3 Assay Kit; the PTPN21, cdk5, ERK1/2 and p-ERK1/2 levels were estimated by qRT-PCR and Western blot. We found that the PTPN21 markedly increased cell viability, inhibited apoptosis. We also found that PTPN21 inhibited caspase-3 activity and down-regulating the Bax/Bcl-2 ratio. Furthermore, the expression of cdk5 protein was up-regulated by PTPN21 by activating ERK1/2 signaling pathway. Finally, our results showed that cdk5 siRNA or ERK1/2 signaling inhibitor PD98059 attenuated the accelerative effect of pcDNA3.1 PTPN21(+) on cell proliferation and apoptosis in PC12 cells. In short, it appears that PTPN21 may protect the PC12 from ischemia injury by upregulating cdk5 via ERK1/2 signaling pathway.

Role of autophagy in regulating the radiosensitivity of tumor cells.

BACKGROUND: Autophagy is a metabolic response of cells to chemical and physical factors, such as nutrition or growth factor deprivation, proinflammatory state, hypoxia, accumulation of reactive oxygen species, presence of infectious agents, and DNA damage. Autophagy maintains the homeostasis of intracellular metabolism mainly by degrading cellular organelles and critical proteins. In a sense, autophagy protects cells from death. Radiotherapy is a powerful tool used to control tumor growth, and it can induce autophagy. The relationship between radiotherapy and autophagy is worthy of further investigation. METHODS: We searched various electronic databases including PubMed for peer-reviewed English-language articles and selected articles on the mechanism of autophagy, its role in cancer development and cancer treatment, and the relationship between the effect of radiation therapy and autophagy intensity. RESULTS: This review has recently shown that the sensitivity of tumor cells to radiation therapy can be increased by regulating autophagy. CONCLUSION: The effects of autophagy vary, and autophagy provides various ways of enhancing radiosensitivity, including inhibition of autophagy, increase in autophagy, and altering the outcome of autophagy.

Enterovirus 71 infection impairs the reproductive capacity of female mice.

Enterovirus 71 (EV71) is a major cause of hand, foot and mouth disease (HFMD); however, no clinically approved vaccine or antiviral treatment is currently available for EV71 infection. In the present study, a murine model of EV71 infection was constructed. The clinical isolates of EV71 were amplified in Vero cells and used to challenge adult mice via hydrodynamic injection (HI) and intraperitoneal injection (IP). Following two challenges, >50% of the mice succumbed to EV71 infection. Surviving female mice were identified to have impaired fertility and their litter sizes were significantly decreased compared with the control group. The antibody against EV71-VP1 persisted in the sera of female mice at a high titer for >2 years after challenge. The maternal antibody in the offspring sera also persisted for ~1 year and disappeared after ~2 years. Results from the present study suggest that a high titer of active EV71 was able to impair the reproductivity of adult female mice, and that high levels of maternal antibody persisted in the offspring and protected postnatal mice from EV71-induced mortality. The promising antigenicity, immunogenicity and reactogenicity of EV71 suggests that it a potential vaccine target that may be beneficial to the control of HFMD, through immunizing infants and women of reproductive age.

Diagnostic and clinical application value of magnetic resonance imaging (MRI) for progressive massive fibrosis of coal worker pneumoconiosis: Case reports.

RATIONALE: Using magnetic resonance imaging (MRI), we diagnosed pneumoconiosis by identifying the content and distribution of hydrogen protons in the water molecules in different tissues and lesions. PATIENT CONCERNS: 25 cases of CWP patients with progressive massive fibrosis (PMF) lesions. DIAGNOSES: Patients were correctly diagnosed, with one case each of Phase I and II pneumoconiosis and 23 cases of Phase III pneumoconiosis. INTERVENTIONS: None. OUTCOMES: Through MRI, 39 PMF pneumoconiosis lesions exhibited equal, low or equally low, and uneven signals on T2WI and fat suppression (SPIR) (38/39, 37/39). LESSONS: MRI has good specificity to identify the characteristics of PMF lesions of CWP, as well as has high application value for the differential diagnosis of lung cancer and other lung tumor-like lesions.

NTN4 is associated with breast cancer metastasis via regulation of EMT-related biomarkers.

Metastasis is the leading cause of death for breast cancer patients. Nerve guidance factor 4 (Netrin-4, NTN4) is reduced in variety of malignancies and involved in tumor metastasis. However, the functions of NTN4 and related molecular mechanisms in breast cancer are poorly understood. Oncomine data revealed that NTN4 was decreased in breast cancer compared with normal breast tissues. For fresh frozen breast cancer samples, significantly depressed expression of NTN4 mRNA was observed in lesion tissues compared with that in adjacent tissues. Afterwards, NTN4 protein level was evaluated in 52 paired breast cancer tissues, and the results were consistent with that in fresh frozen samples. NTN4 expression was upregulated using NTN4-pcDNA3.1 plasmid in MDA-MB-231 cells and silenced using NTN4 small interfering RNA (siRNA) in Hs578T cells. Then the effects of NTN4 overexpression or knockdown on breast cancer cell migration and invasion were investigated. The results manifested that NTN4 overexpression attenuated cell migration and invasion, and induced N-cadherin and vimentin downregulation, while NTN4 siRNA-transfected cells had a significant increase in migration and invasion, as well as upregulation in N-cadherin and vimentin expression. These results demonstrate that NTN4 is reduced in breast cancer tissues and NTN4 is associated with breast cancer cell migration and invasion via regulation of epithelial mesenchymal transition (EMT)-related biomarkers.

Effect of GEN1 interference on the chemosensitivity of the breast cancer MCF-7 and SKBR3 cell lines.

Chemotherapy is a notable method for the treatment of breast cancer. Numerous genes associated with the sensitivity of cancer to chemotherapy have been found. In recent years, evidence has suggested that a particular structure termed Holliday junction (HJ) plays a crucial role in cancer chemosensitivity. Targeting HJ resolvases, such as structure-specific endonuclease subunit SLX4 (Slx4) and MUS81 structure-specific endonuclease subunit (Mus81), significantly increases the chemosensitivity of tumor cells. Flap endonuclease GEN homolog 1 (GEN1) is a HJ resolvase that belongs to the Rad2/xeroderma pigmentosum complementation group G nuclease family. Whether GEN1 affects the chemosensitivity of tumor cells in a similar manner to Slx4 and Mus81 remains unknown. The aim of the present study was to determine the effect of GEN1 interference on the chemosensitivity of breast cancer cell lines. The investigation of the function of GEN1 was performed using MCF-7 and SKBR3 cells. Short hairpin RNA was used to suppress the expression of GEN1, and western blot analysis and reverse transcription-quantitative polymerase chain reaction were used to detect gene expression. In addition, a cell counting kit-8 assay was performed to detect the viability of cells and flow cytometry was performed to test apoptosis levels. Suppression of GEN1 in SKBR3 cells effectively increased the sensitivity to the chemotherapeutic drug 5-fluorouracil (5-FU), while MCF-7 cells showed no significant change in sensitivity following GEN1 suppression. However, when GEN1 was targeted in addition to Mus81, the MCF-7 cells also demonstrated a significantly increased sensitivity to 5-FU. In addition, when the level of Mus81 was low, GEN1 expression was increased under a low concentration of 5-FU. The present results suggest that GEN1 may play different roles in different breast cancer cell lines. The function of GEN1 may be affected by the level of Mus81 in the cell line. In addition, GEN1 interference may improve the sensitivity to chemotherapy induced by targeting Mus81 alone.

SPAG9 is involved in hepatocarcinoma cell migration and invasion via modulation of ELK1 expression.

BACKGROUND: Sperm-associated antigen 9 (SPAG9) is upregulated in several malignancies and its overexpression is positively correlated with cancer cell malignancies. However, the specific biological roles of SPAG9 in hepatocellular carcinoma (HCC) are less understood. METHODS: We analyzed SPAG9 and ETS-like gene 1, tyrosine kinase (ELK1) expression in 50 paired HCC specimens and adjacent noncancerous liver specimens using immunohistochemistry. SPAG9 small interfering RNA (siRNA) was used to knockdown SPAG9 expression in HCCLM3 and HuH7 cell lines. We used plasmids to upregulate ELK1 expression and siRNA to downregulate ELK1 expression in HuH7 cells. Quantitative real-time polymerase chain reaction and Western blot were used to evaluate the expression of SPAG9 and ELK1 at the mRNA and protein level, respectively. Wound healing, matrigel migration, and invasion analyses were performed to determine the effect of SPAG9 and ELK1 on HCC metastasis. RESULTS: SPAG9 and ELK1 were overexpressed in HCC tissue specimens and their expressions were higher in HCCLM3 and HuH7 cells compared to the low-metastatic HepG2 cells. Overexpression of SPAG9 was positively associated with tumor-node-metastasis staging (P=0.032), metastasis parameters (P=0.018) of HCC patients, and ELK1 expression (r=0.422, P<0.001) in HCC tissue specimens. In addition, knockdown of SPAG9 in HCCLM3 and HuH7 cells using siRNA significantly suppressed cell migration and invasion. Furthermore, we observed inhibition of ELK1 expression and p38 signaling. However, ELK1 overexpression reversed the inhibitory effects of SPAG9 siRNA on HCC cell metastasis and ELK1 depletion inhibited HuH7 cell migration and invasion. CONCLUSION: SPAG9 overexpression was positively correlated with HCC metastasis and SPAG9-induced migration and invasion were partially dependent on ELK1 expression in HCC cell lines. These results suggest that SPAG9 may be a potential anti-metastasis target effective in HCC therapy.

Direct targeting sperm-associated antigen 9 by miR-141 influences hepatocellular carcinoma cell growth and metastasis via JNK pathway.

BACKGROUND: The aberrant expression of sperm-associated antigen 9 (SPAG9) is associated with numerous cancers, including hepatocellular carcinoma (HCC). The exploration of molecules and mechanisms regulating SPAG9 expression may provide new options for HCC therapy. METHODS: MiRNA target prediction programs were used to explore SPAG9-targeted miRNAs. SPAG9 and miR-141 expression were detected in HCC tissues and cell lines by Western blot and real-time PCR. Dual-luciferase reporter assay was utilized to validate SPAG9 as a direct target gene of miR-141. Cell proliferation, invasion, and migration assays were used to determine whether miR-141-mediated regulation of SPAG9 could affect HCC progression. RESULTS: An inverse correlation was observed between SPAG9 and miR-141 expression in HCC tissues and cell lines. Dual-luciferase reporter assay further showed that SPAG9 was a direct target gene of miR-141. The ectopic expression of miR-141 could markedly suppress SPAG9 expression in HCC cells. MiR-141 overexpression also resulted in significantly reduced cell proliferation, invasion, and migration, and imitation of the SPAG9 knockdown effects on HCC cells. Furthermore, SPAG9 restoration in miR-141-expressing cells sufficiently attenuated the tumor-suppressive effects of miR-141. Finally, JNK activity was found to be reduced by miR-141 overexpression the same way as by SPAG9 silencing. The overexpression of SPAG9 lacking its 3'-UTR significantly restored JNK activity and its downstream genes in miR-141-transfected HCC cells. CONCLUSION: MiR-141 suppression may cause aberrant expression of SPAG9 and promote HCC tumorigenesis via JNK pathway.

Inhibition of Mus81 by siRNA enhances sensitivity to 5-FU in breast carcinoma cell lines.

PURPOSE: One of the most challenging aspects of breast carcinoma chemotherapy is the rapid acquirement of drug resistance. Improving the sensitivity to chemotherapeutic drugs is very important for successful treatment. Mus81 plays an important role in maintaining the stability of the genome and DNA repair. However, recent studies suggested that Mus81 expression levels correlate well with resistance to DNA-damaging drugs. The present study aimed to investigate the role of Mus81 on the chemosensitivity of breast carcinoma cells in response to 5-fluorouracil (5-FU), a chemotherapeutic drug that is widely used for treatment of breast malignancies. METHODS: The expression of Mus81 in MCF-7 and T47D cells was suppressed by small interfering RNA (siRNA). mRNA and protein levels of Mus81 were analyzed by quantitative real-time polymerase chain reaction and Western blot. Cell viability and colony survival were determined by Cell Counting Kit-8 and plate colony formation assay, respectively. Cell cycle and apoptosis were detected by flow cytometry. RESULTS: 5-FU inhibited the cell viability of MCF-7 and T47D cells in a concentration-dependent manner. We found that the Mus81-silenced MCF-7 and T47D cells exhibited decreased cell viability and clonogenic survival, but increased G2 accumulation, in response to 5-FU. In addition, Mus81 deficiency resulted in increased apoptosis and p53 expression in MCF-7 after 5-FU treatment. However, Mus81 deficiency did not affect the apoptosis of T47D cells with 5-FU. CONCLUSION: Taken together, our data suggest that Mus81 inhibition significantly increased the chemosensitivity of MCF-7 and T47D cells in response to 5-FU. Thus, Mus81 siRNA is potentially a useful adjuvant strategy for breast cancer chemotherapy.

Transient folate deprivation in combination with small-molecule compounds facilitates the generation of somatic cell-derived pluripotent stem cells in mice.

Induced pluripotent stem cells (iPSCs) can be propagated indefinitely, while maintaining the capacity to differentiate into all cell types in the body except for the extra-embryonic tissues. This iPSC technology not only represents a new way to use individual-specific stem cells for regenerative medicine but also constitutes a novel method to obtain large numbers of disease-specific cells for biomedical research. However, the low efficiency of reprogramming and genomic integration of oncogenes and viral vectors limit the potential application of iPSCs. Chemical-induced reprogramming offers a novel approach to generating iPSCs. In this study, a new combination of small-molecule compounds (SMs) (sodium butyrate, A-83-01, CHIR99021, Y-27632) under conditions of transient folate deprivation was used to generate iPSC. It was found that transient folate deprivation combined with SMs was sufficient to permit reprogramming from mouse embryonic fibroblasts (MEFs) in the presence of transcription factors, Oct4 and Klf4, within 25 days, replacing Sox2 and c-Myc, and accelerated the generation of mouse iPSCs. The resulting cell lines resembled mouse embryonic stem (ES) cells with respect to proliferation rate, morphology, pluripotency-associated markers and gene expressions. Deprivation of folic acid, combined with treating MEFs with SMs, can improve the inducing efficiency of iPSCs and reduce their carcinogenicity and the use of exogenous reprogramming factors.

Transient folate deprivation facilitates the generation of mouse-induced pluripotent stem cells.

Somatic cells can be reprogrammed into iPS (induced pluripotent stem) cells through the ectopic expression of defined transcription factors. However, the inefficiency and amount of time needed limited the potential application of iPS cells. We report an efficient method to generate iPS cells from MEF (mouse embryonic fibroblasts) through folate-depriviatoin, which was used to change the methylation of MEF. Without folate for 3 days, the induction efficiency is enhanced fivefold. Karyotype analysis showed that transient folate-depriving treatment did not negatively affect properties of iPS cells; characterised iPS cells show normal karyotypes. Thus, a new method has been found that can improve the induction efficiency, but not increase the chance of chromosomal mutation.

Lipoxin A4 inhibits the production of proinflammatory cytokines induced by ß-amyloid in vitro and in vivo.

Studies increasingly indicate that inflammation induced by ß-amyloid (Aß) contributes to the progression of Alzheimer's disease (AD). How to inhibit the enhanced production of proinflammatory cytokines stimulated by Aß is an important research subject for the treatment of AD. In this study, we investigated the inhibitory effect and the molecular mechanism of the lipoxin A(4) (LXA(4)) on the production of interleukin-1ß (IL-1ß) and tumor necrosis factorα (TNFα) induced by ß-amyloid in the cortex and hippocampus of mice, and in Aß-stimulated BV2 cells, a mouse microglial cell line. LXA(4) down-regulated the protein expression of IL-1ß and TNFα, attenuated the gene expressions of IL-1ß and TNFα, inhibited the degradation of IκBα, inhibited translocation of NF-κB p65 subunit into the nucleus induced by ß-amyloid in the cortex and hippocampus of mice, and in Aß-stimulated BV2 cells, and the inhibitory effects were dose dependently elevated. Our findings suggest that LXA(4) inhibits the production of IL-1ß and TNFα induced by ß-amyloid in the cortex and hippocampus of mice, and in BV2 microglial cells via the NF-κB signal pathway.