Profilin 1 potentiates apoptosis induced by staurosporine in cancer cells

The correlation between the loss of Profilin 1 (Pfn1) with tumor progression indicated that Pfn1 is a tumor suppressor in human carcinoma. The molecular mechanisms underlying Pfn1 tumor suppression has yet to be elucidated. In this study, we showed that Pfn1 overexpression sensitizes cancer cells to apoptosis through the typical intrinsic apoptotic pathway. Mechanistically, the increased Pfn1 expression mediated the upregulation of p53R273H, one of the most common tumor-associated hotspot mutations of p53, with transactivation deletion in tumorigenesis and increased localization of p53R273H in cytoplasm. Further studies showed that mutant p53R273H was involved in apoptosis induced by Staurosporine (STS) via transcription-independent mitochondrial functions. We observed (i) the increased cytosolic localization of p53R273H, (ii) the activation of phosphorylation at Ser15, (iii) its mitochondrial localization; Pfn1 acted as a positive regulator of these processes. We also found that Pfn1 interacted with p53R273H and thus facilitated its exertion over the transcription-independent activity in the cytoplasm during drug action. Our results define a new function and mechanism of Pfn1 demonstrating that the combined effect with apoptotic agents led to a synergistic increase in apoptosis. In addition, p53R273H abrogating DNA binding was found to play a major role in the Pfn1- sensitized apoptosis through a transactivation-independent and cytosolic activity.

Up-regulation of MBD1 promotes pancreatic cancer cell epithelial-mesenchymal transition and invasion by epigenetic down-regulation of E-cadherin

Methyl-CpG binding domain protein 1 (MBD1) has been implicated in transcriptional regulation, heterochromatin formation, genomic stability, cell-cycle progression and development. It is also predicted that MBD1 might be involved in tumor development and progression. However, whether and how MBD1 is involved in tumorigenesis, especially in pancreatic cancer (PC), is currently unknown. We found that MBD1 was significantly up-regulated in PC tissues compared with the surrounding normal tissues according to RT-PCR data. Tissue microarray (TMA) based immunohistochemical study from 58 surgically resected PC specimens indicated that higher MBD1 expression correlated with lymph node metastasis and poor survival in PC patients. Gain- and loss-of-function studies in vitro validated MBD1 as a potent oncogene promoting PC cell invasion as well as epithelial-mesenchymal transition (EMT). Mechanistically, MBD1 is associated with Twist and NAD-dependent deacetylase sirtuin-1 (SIRT1), thereby forming the Twist-MBD1-SIRT1 complex on the CDH1 promoter, which resulted in reduced E-cadherin transcription activity and increased cell EMT ability. Significantly, targeting MBD1 reversed the EMT phenotype of PC and restored sensitivity to chemotherapy. Taken together, the results of our study revealed a novel function of MBD1 in PC invasion and metastasis by providing a molecular mechanism underlying MBD1-promoted EMT. Thus MBD1 may serve as a potential therapeutic target for PC.

Galectin-1 prolongs survival of mouse liver allografts from Flt3L-pretreated donors

Liver allografts are spontaneously accepted across MHC barriers in mice. The mechanisms underlying this phenomenon remain poorly understood. Galectin-1, an endogenous lectin expressed in lymphoid organs, plays a vital role in maintaining central and peripheral tolerance. This study was to investigate the role of galectin-1 in spontaneous tolerance of liver allografts in mice, and to evaluate the therapeutic effects of galectin-1 on liver allograft rejection induced by donor Flt3L pretreatment. Blockade of the galectin-1 pathway via neutralizing antigalectin-1 mAb did not affect survival of the liver allografts from B6 donors into C3H recipients. Administration of rGal-1 significantly prolonged survival of liver allografts from Flt3L-pretreated donors and ameliorated Flt3L-triggered liver allograft rejection. This effect was associated with increased apoptosis of T cells in both allografts and spleens, decreased frequencies of Th1 and Th17 cells, decreased expression of Th1-associated cytokines (IL-12, IL-2 and IFN-γ), Th17-associated cytokines (IL-23 and IL-17) and granzyme B, in parallel with selectively increased IL-10 expression in liver allografts. In vitro, galectin-1 inhibited Flt3L-differentiated DC-mediated proliferation of allo-CD4(+) T cells and production of IFN-γ and IL-17. These data provide new evidence of the potential regulatory effects of galectin-1 in alloimmune responses in a murine model of liver transplantation.

ANXA2 remodels the microstructures of caco2 cells

ANXA2 was reported as a multiple tumors relevant gene expressed excessively in many tumor tissue types, especially in the cancers from digestion system, and its aberrant expression enhances the malignant properties of cancer cells. We suppose that the microstructure heterogeneity is important to maintain the malignancy of cancer cells, and excessive ANXA2 expression enhance the malignancy by remodeling the microstructures of cancer cells. To validate the proposal, the ANXA2-/-caco2 cell line was generated and the changes of the microstructures in the ANXA2 deleted and wild type caco2 cells were observed under fluorescence microscope, laser scanning confocal microscope and electron microscope. We found that ANXA2 deletion induced the pseudopodia shorted and spared, non-stained areas increased, mitochondria decreased, and the expression and polymerization of F-actin and β-tubulin changed. By the findings above, it is firstly reported in this paper that the ANXA2 excessive expression induces the significant changes of the microstructures in cancer cells. Combining our previous data together, our results indicate that ANXA2 excessive expression enhances the malignancy of cancers partially by remodeling the cell microstructures.

Pulsed radiofrequency treatment for idiopathic trigeminal neuralgia: a retrospective analysis of the causes for ineffective pain relief

We retrospectively analyzed the reasons for ineffective pain relief in patients with idiopathic trigeminal neuralgia (TN) who had undergone pulsed radiofrequency (PRF) treatment guided by computed tomography scan. We found that intraoperative PRF output voltage and electrical field intensity was significantly higher (p < 0.05) in the group who had received effective treatment than in the ineffective group. These findings suggest that optimizing PRF parameters and increasing the intraoperative output voltage (electric field intensity) may therefore, provide better pain relief in patients with TN.

Late onset systemic lupus erythematosus with severe hypercalcaemia

We report a case of a 76-year old female presenting with symptomatic severe hypercalcaemia, and subsequently diagnosed with late onset SLE due to the presence of anaemia, leucopenia, antibodies of antinuclear (ANA), anti-dsDNA, and also kidney impairment. Serum levels of FGF23 and intact-parathyroid hormone (iPTH) were low in this patient. Serum calcium, FGF23 and iPTH levels responded to steroids, which occurred simultaneously with disease activity. On follow-up, the faster increase in FGF23 than in parathyroid hormone suggested that FGF23 might be involved in the pathogenesis of hypercalcaemia in SLE.

Hylan G-F 20 maintains cartilage integrity and decreases osteophyte formation in osteoarthritis through both anabolic and anti-catabolic mechanisms

OBJECTIVE

To perform a molecular mechanism-based investigation of the chondroprotective potential of hylan G-F 20.

METHOD

The effects of hylan G-F 20 on IL-1β-induced glycosaminoglycan (GAG) depletion and matrix metalloproteinase (MMP) expression in bovine and human cartilage explants were evaluated. Three weekly intra-articular hylan G-F 20 or control injections were administered 4 weeks post-operatively to rabbits with surgically induced osteoarthritis (OA). Cartilage histopathologic scores and osteophyte size were evaluated at 1, 4, and 8 weeks post-injections. Histomorphometry and immunostaining were used to quantify cartilage area and type II collagen (Col II) intensity, and real-time polymerase chain reaction (PCR) was used to examine the mRNA levels of Col2A1, MMP-13, -16 and IL-1β at 1 week.

RESULTS

Hylan G-F 20 retained GAG in IL-1β-exposed bovine and human cartilage explants and abrogated IL-1β-mediated increases in MMP-1, -3, and -13 in human explant culture. Hylan G-F 20‒treated OA joints had significantly better cartilage integrity at 1 and 4 weeks post-treatment and significantly smaller osteophytes at 4 weeks compared with control. Col2A1 mRNA increased with hylan G-F 20 treatment, which correlated with a trend toward increased Col II immunostaining. MMP-13 and -16 mRNAs increased in OA cartilage, but were not significantly altered by hylan G-F 20. IL-1β mRNA was undetectable in cartilage and unaltered in the synovium.

CONCLUSIONS

Hylan G-F 20 improved cartilage integrity and decreased osteophyte formation in the rabbit model of OA. Our results suggest that hylan G-F 20 may stimulate cartilage repair by increasing Col II, and inhibit IL-1β-mediated matrix degradation by decreasing MMPs.

Suicidal thoughts and behaviors in older adults in rural China: a preliminary study

BACKGROUND

One purpose of this study was to examine the feasibility of conducting epidemiological survey on suicidal thoughts and behaviors (hereafter "suicidal thoughts/behaviors"; i.e., any suicidal ideation, serious ideation, planning, and attempts) among older adults in rural China. Another purpose was to investigate among older people in rural China the prevalence of suicidal thoughts/behaviors, as well as their sociodemographic and clinical correlates.

METHODS

A randomly selected sample of 263 subjects, 50 years or older, was recruited in a remote rural area of Southwestern China (Mianyang Region, Sichuan Province) and interviewed using structured instruments. Basic sociodemographic and clinical data were collected.

RESULTS

There was no refusal among approached subjects, and subjects were willing to answer questions on suicidal thoughts/behaviors. The lifetime prevalence of suicidal ideation, serious ideation, planning, and attempt was 28.9% (23.4%-34.4%), 19.7% (14.9%-24.6%), 11.4% (7.5%-15.3%), and 5.3% (2.6%-8.1%), respectively. The corresponding 12-month prevalence was 8.8% (5.3%-12.2%), 5.3% (2.6%-8.1%), 2.7% (0.7%-4.6%), and 0%, respectively. The 2-week prevalence was 3.4% (1.2%-5.6%), 2.3% (0.5%-4.1%), 2.3% (0.5%-4.1%), and 0%, respectively. Correlates of suicidal thoughts/behaviors of this group are similar to findings from other community studies, such as female gender, unmarried status, major medical conditions, insomnia, financial difficulties and lower education, depressive symptoms, recent stressful life events, greater life dissatisfaction.

CONCLUSIONS

Our findings suggest that larger scale epidemiological survey of suicidal thoughts/behaviors on older adults in rural China would be feasible. Suicidal thoughts/behaviors are common among older people in rural China, as seen in this preliminary study, which points to the need for further larger scale investigations.

Paediatric bacterial keratitis cases in Shanghai: microbiological profile, antibiotic susceptibility and visual outcomes

PURPOSE

The purpose of this study was to review the microbiological profile, in vitro antibiotic susceptibility and visual outcomes of paediatric microbial keratitis in Shanghai, China over the past 6 years.

METHODS

Medical records of patients aged ≤16 years were reviewed, who were diagnosed as having bacterial keratitis between 1 January 2005 and 31 December 2010. Bacterial culture results and in vitro antibiotic susceptibility were analysed. A logistic regression analysis was conducted to evaluate the relationship between visual impairment and possible risk factors.

RESULTS

Eighty consecutive cases of paediatric bacterial keratitis cases were included, among which 59 were identified as having positive culture. Staphylococcus epidermidis was the most commonly isolated organism (n=23; 39.0%), followed by Streptococcus pneumoniae (n=11; 18.6%) and Pseudomonas aeruginosa (n=6; 10.2%). Antibiotic sensitivities revealed that tested bacteria had low resistance rates to fluoroquinolones and aminoglycosides (8.3-18.4% and 12.5-24.4%, respectively). Multivariate logistic regression analysis proved that visual impairment was significantly associated with Gram-negative bacterial infection (odds ratio (OR)=7.626; P=0.043) and an increasing number of resistant antibiotics (OR=0.385; P=0.040).

CONCLUSIONS

S. epidermidis was the most common isolated organism in Shanghai paediatric keratitis. The fluoroquinolones and aminoglycosides remained good choices for treating these patients. Gram-negative bacterial infection and an increasing number of resistant antibiotics were associated with worse visual prognoses in paediatric keratitis.

Hypertonic saline reduces lipopolysaccharide-induced mouse brain edema through inhibiting aquaporin 4 expression

INTRODUCTION

Three percent sodium chloride (NaCl) treatment has been shown to reduce brain edema and inhibited brain aquaporin 4 (AQP4) expression in bacterial meningitis induced by Escherichia coli. Lipopolysaccharide (LPS) is the main pathogenic component of E. coli. We aimed to explore the effect of 3% NaCl in mouse brain edema induced by LPS, as well as to elucidate the potential mechanisms of action.

METHODS

Three percent NaCl was used to treat cerebral edema induced by LPS in mice in vivo. Brain water content, IL-1β, TNFα, immunoglobulin G (IgG), AQP4 mRNA and protein were measured in brain tissues. IL-1β, 3% NaCl and calphostin C (a specific inhibitor of protein kinase C) were used to treat the primary astrocytes in vitro. AQP4 mRNA and protein were measured in astrocytes. Differences in various groups were determined by one-way analysis of variance.

RESULTS

Three percent NaCl attenuated the increase of brain water content, IL-1β, TNFα, IgG, AQP4 mRNA and protein in brain tissues induced by LPS. Three percent NaCl inhibited the increase of AQP4 mRNA and protein in astrocytes induced by IL-1β in vitro. Calphostin C blocked the decrease of AQP4 mRNA and protein in astrocytes induced by 3% NaCl in vitro.

CONCLUSIONS

Osmotherapy with 3% NaCl ameliorated LPS-induced cerebral edema in vivo. In addition to its osmotic force, 3% NaCl exerted anti-edema effects possibly through down-regulating the expression of proinflammatory cytokines (IL-1β and TNFα) and inhibiting the expression of AQP4 induced by proinflammatory cytokines. Three percent NaCl attenuated the expression of AQP4 through activation of protein kinase C in astrocytes.