Silencing of osteopontin promotes the radiosensitivity of breast cancer cells by reducing the expression of hypoxia inducible factor 1 and vascular endothelial growth factor

Background  Osteopontin (OPN) is a secreted phosphoglycoprotein (SSP) that is overexpressed in a variety of tumors and was regarded as a molecular marker of tumors. In this study, we intended to demonstrate the role of OPN in human breast cancer cell line MDA-MB-231.

Methods  Recombinant plasmid expressing small interfering RNA (siRNA) specific to OPN mRNA was transfected into MDA-MB-231 cells to generate the stable transfected cell line MDA-MB-343, and the empty plasmid tansfected cells (MDA-MB-neg) or wildtype MDA-MB-231 cells were used as control cells respectively. Expression of OPN, hypoxia inducible factor-1 (HIF-1) and vascular endothelial growth factor (VEGF) proteins was analyzed by Western blotting analysis. The radiosensitivity of cells was determined by detecting cell apoptosis, cell proliferation and cell senescence.

Results  HIF-1 and VEGF proteins in MDA-MB-343 cells were significantly downregulated upon the efficient knockdown of OPN expression under either hypoxia or normoxia environment. Moreover, expression of OPN protein was upregualted upon hypoxic culture. Stable OPN-silencing also decreased cell invasion, increased cell apoptosis and cell senescence, as well as reduced clonogenic survival, resulting in increase radiation tolerance.

Conclusions  Suppression of OPN gene expression can enhance radiosensitivity and affect cell apoptosis in breast cancer cells. OPN seems to be an attractive target for the improvement of radiotherapy.

     

Effects of estrogen on collagen gel contraction by human retinal glial cells

Background  There are definite gender differences in patients with macular holes. Menopausal women over 50 years are most affected. We aimed to observe the effect of estrogen on collagen gel contraction by cultured human retinal glial cells. It is speculated that estrogen could strengthen the tensile stress of the macula by maintaining the correct morphology and contraction.

Methods  Estrogen was used to determine its effects on collagen gel contraction, and its function was measured using morphological changes in cells. Human retinal glial cells were cultured in collagen solution. The cells were then exposed to collagen gels and the degree of contraction of the gel was determined.

Results  Estrogen at differing concentrations had no effect on the growth of human retinal glial cells. However, after exposed to collagen gel block, less contraction was noted in the estrogen-treated group than in the control group.

Conclusions  Estrogen can inhibit collagen gel contraction by glial cells. These results suggest a mechanism for macular hole formation, which is observed in menopausal females.

     

Specific regulator of eosinophil apoptosis: Siglec-8—new hope for bronchial asthma treatment

Objective  It is known that Siglec-8 is selectively expressed on human eosinophils at a high level and mediates eosinophil apoptosis when crosslinked with its antibody. The aim of our review is to elucidate the molecular and biological characteristic of Siglec-8 and then discuss the function and possible mechanisms of Siglec-8 in eosinophils. Thereby, we will expand our understanding to the regulation of eosinophil apoptosis, and provide important clues to the treatment of asthma and other hyper-eosinophilic diseases.

Data sources  Most articles were identified by searching of PubMed online resources using the key term Siglecs.

Study selection  Mainly original milestone articles and critical reviews written by major pioneer investigators in the field were selected.

Results  Siglec-8 is selectively expressed on human eosinophil and can specifically induce eosinophil apoptosis.

Conclusion  The restricted expression of Siglec-8 on human eosinophil and the rapid progress in understanding its role as cell signaling and activation of death receptors have made it an attractive target for treatment of asthma and other hyper-eosinophilic diseases.

     

AMP-activated protein kinase acts as a negative regulator of high glucose-induced RANKL expression in human periodontal ligament cells

Background  It is well known that the function of periodontal ligament cells may be affected by high glucose levels. This study investigated the direct effect of high glucose on the expression of receptor activator of nuclear factor-kappa B ligand (RANKL) in human PDL (hPDL) cells. In addition, we examined whether this effect was mediated via AMPK activation.

Methods  We examined the expression of osteoprotegerin in hPDL cells cultured at different concentrations of glucose using real-time polymerase chain reaction (PCR), and Western blotting analysis. AMPK phosphorylation in hPDL cells was studied using immunoprecipitate kinase assay and Western blotting. The effect of AMPK activation on RANKL expression in hPDL cells was investigated by real-time PCR and Western blotting.

Results  High glucose levels caused an increase in RANKL mRNA and protein expression in hPDL cells. Moreover, the amount of p-AMPK and AMPK activity was lower in hPDL cells exposed to high glucose levels than in cells exposed to normal glucose levels. Suppression of AMPK by Compound C augmented RANKL expression, and AMPK activation by metformin significantly decreased RANKL expression in hPDL cells. Additionally, metformin down-regulated RANKL expression in hPDL cells exposed to high glucose via AMPK activation.

Conclusion  High glucose-induced up-regulation of RANKL could be due to decreased AMPK activity, and AMPK activation may be involved in regulating of RANKL expression in hPDL cells.

     

Endothelial progenitor cell down-regulation in a mouse model of Kawasaki disease

Background  Cardiovascular complications of Kawasaki disease (KD) are a common cause of heart disease in pediatric populations. Previous studies have suggested a role for endothelial progenitor cells (EPCs) in coronary artery lesions associated with KD. However, long-term observations of EPCs during the natural progression of this disorder are lacking. Using an experimental model of KD, we aimed to determine whether the coronary artery lesions are associated with down-regulation of EPCs.

Methods  To induce KD, C57BL/6 mice were administered an intraperitoneal injection of Lactobacillus casei cell wall extract (LCWE; phosphate buffered saline used as control vehicle). Study groups included: group A (14 days following LCWE injection), group B (56 days following LCWE injection) and group C (controls). Numbers of circulating EPCs (positively staining for both CD34 and Flk-1 while staining negative for CD45) were evaluated using flow cytometry. Bone marrow mononuclear cells were cultured in vitro to expand EPCs for functional analysis. In vitro EPC proliferation, adhesion and migration were assessed.

Results  The model was shown to exhibit similar coronary artery lesions to KD patients with coronary aneurysms. Numbers of circulating EPCs decreased significantly in the KD models (groups A and B) compared to controls ((0.017±0.008)% vs. (0.028±0.007)%, P <0.05 and (0.016±0.007)% vs. (0.028±0.007)%, P <0.05). Proliferative, adhesive and migratory properties of EPCs were markedly impaired in groups A and B.

Conclusion  Coronary artery lesions in KD occur as a consequence of impaired vascular injury repair, resulting from excess consumption of EPCs together with a functional impairment of bone marrow EPCs and their precursors.

     

Rho-associated coiled kinase inhibitor Y-27632 promotes neuronal-like differentiation of adult human adipose tissue-derived stem cells

Background  Y-27632 is a specific inhibitor of Rho-associated coiled kinase (ROCK) and has been shown to promote the survival and induce the differentiation of a variety of cells types. However, the effects of Y-27632 on adult human adipose tissue-derived stem cells (ADSCs) are unclear. This study aimed to investigate the effects of Y-27632 on the neuronal-like differentiation of ADSCs.

Methods  ADSCs were isolated from women undergoing plastic surgery and cultured. ADSCs were treated with different doses of Y-27632 and observed morphological changes under microscope. The expression of nestin, neuron specific enolase (NSE) and microtubule-associated protein-2 (MAP-2) in ADSCs treated with Y-27632 was detected by immunocytochemistry and Western blotting analysis.

Results  Y-27632 had the potency to induce neuronal-like differentiation in ADSCs in a dose-dependent manner. Moreover, the differentiation induced by Y-27632 was recovered upon drug withdraw. ADSCs treated with Y-27632 expressed neuronal markers such as NSE, MAP-2 and nestin while untreated ADSCs did not express these markers.

Conclusion  Selective ROCK inhibitor Y-27632 could potentiate the neuronal-like differentiation of ADSCs, suggesting that Y-27632 could be utilized to induce the differentiation of ADSCs to neurons and facilitate the clinical application of ADSCs in tissue engineering.

     

Antiviral therapy of decompensated hepatitis B virus-related cirrhosis

Objective  To review the development, mechanism, necessity and limitation of antiviral therapy in decompensated hepatitis B virus-related cirrhosis.

Data sources  Most information was pulled from a literature search (Pubmed 2000 to 2011) using the keywords of antiviral and decompensated hepatitis B virus-related cirrhosis. Relevant book chapters were also reviewed.

Study selection  Well-controlled, prospective landmark studies and review articles on antiviral therapy in decompesated hepatitis B virus-related cirrhosis were selected.

Results  Specific antiviral agents not only control viral replication, which permits liver transplantation, but also improve liver function so significantly that patients could be removed from the transplant waiting list. However, the emergence of drug-resistant mutants can result in treatment failure. Combination therapy is a save-strategy in drug-resistant.

Conclusions  Although the treatment of end-stage liver disease is still a challenge worldwide, antiviral therapy has altered the natural history of hepatitis B patients with decompensated cirrhosis. The approval of the new generation of antivirals is opening new perspectives for finding the optimal antiviral treatment for patients with decompensated cirrhosis and preventing antiviral resistance. A combination of antivirals may be one of the future strategies for fulfilling these goals.

     

Effect of combination therapy with alginate dressing and mouse epidermal growth factor on epidermal stem cells in patients with refractory wounds

Background  The aim of this research was to determine the efficacy of combination therapy using an alginate dressing and mouse epidermal growth factor (mEGF) on proliferation and differentiation of epidermal stem cells (ESCs) in patients with refractory wounds.

Methods  Eighteen patients (12 males and 6 females, aged from 18 to 61 years (mean 36.4 years)) with various skin wounds, were treated by dressing changing for one month. The wounds were located in the foot (11), calf (3), thigh (2) and forearm (2). The patients were randomly divided into 3 groups: alginate dressing and mEGF (group A; n=6), mEGF (group B; n=6) and control (group C; n=6). Wound closure indexes were measured at 7, 14, 21 and 28 days. Samples were harvested for pathologic examination, at 7 and 14 days following treatment. Cytokeratin 10 (CK10) and cytokeratin 15 (CK15) positive cells were evaluated using the super-sensitivity (SP) immunohistochemical staining technique.

Results  Wound healing was promoted in groups A and B. In group A, the wound closure index was increased significantly (P <0.05), and in one case the maximum cure area reached 102 cm². Pathological examination identified a thicker epidermis, active angiogenesis and enhanced granulation in group A compared with groups B and C. Using the SP immunohistochemical staining technique, we showed that ESCs in group A were bigger in size and larger in number than in groups B and C. Overall, there was a significant difference in ESCs proliferation and differentiation between group A and group B (or C).

Conclusions  Combination therapy using an alginate dressing and mEGF shows increased proliferation and differentiation of ESCs in patients with refractory wounds compared with those treated with mEGF alone.

     

Proteomic analysis for detecting serum biomarkers related to smoking in humans

Background  Smoking is the leading cause of death in the world. This study focused on the difference of the serum proteomic profiling between healthy smokers and nonsmokers in order to find smoking-specific serum biomarkers.

Methods  Pattern-based proteomic profiling of 100 serum samples (from 50 Chinese male smokers and 50 matched nonsmokers) was performed through magnetic bead fractionation coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis (MALDI-TOF-MS) and resulting data were statistically analyzed by Ciphergen ProteinChip software 3.0.2.

Results  We found 72 serum peaks were significantly different between smokers and nonsmokers (P <0.05). Marker peaks of mass-to-charge ratio (m/z) 3159.13, 7561.03 and 9407.32 were smoking-specific.

Conclusion  The preliminary data suggested that smoking-specific serum biomarkers could be detected in humans.

     

创伤骨科患者创伤严重程度和血浆D二聚体水平的相关分析

Background  The correlation between the plasma D-dimer level and deep vein thrombosis has not been conclusive in various studies. The aim of this research was to study the relationship between plasma D-dimer levels and the severity of orthopedic trauma by retrospective examination of orthopedic trauma cases.

Methods  Clinically acute trauma and non-acute trauma patients were selected and their plasma D-dimer levels were measured. Plasma D-dimer levels in patients of these two groups were compared. The relationship between the plasma D-dimer level and the severity of the trauma was also studied.

Results  There were 548 cases in the acute trauma group and 501 cases in the non-acute trauma group. The levels of plasma D-dimer were significantly higher in the acute trauma group than in the non-acute trauma group (P <0.01). In the acute trauma group, the correlation between the D-dimer level and the number of fractures was a positive linear correlation (r=0.9532).

Conclusions  Elevated plasma D-dimer is common in trauma patients. The D-dimer level and the number of fractures in the trauma patients are closely correlated. D-dimer is not only an indicator for the diagnosis of deep vein thrombosis and pulmonary embolus, but also an indicator of the severity of trauma in acute trauma patients.

     

Gene delivery in peritoneal dialysis related peritoneal fibrosis research

Objective  To summarize the development of gene delivery vectors in peritoneal fibrosis research and discuss the feasibility and superiority of lentiviral vectors.

Data sources  The data in this article were collected from PubMed database with relevant English articles published from 1995 to 2011.

Study selection  Articles regarding the gene therapy in peritoneal fibrosis research using non-viral vectors, adenoviral vectors, retroviral vectors, and lentiviral vectors were selected. Data were mainly extracted from 60 articles, which are listed in the reference section of this review.

Results  Non-viral vector-mediated gene delivery (including naked DNA for ex vivo, oligonucleotides, ultrasound- contrast agent mediated naked gene delivery, etc.) and viral vector-mediated gene delivery (including adenovirus, helper-dependant adenovirus, and retrovirus vectors) have been successfully applied both in the mechanistic investigation and the potential prevention and treatment of peritoneal fibrosis.

Conclusions  Peritoneal fibrosis is a major complication of peritoneal dialysis (PD). Recently, the wide use of the gene delivery technique made it possible to access and further research peritoneal fibrosis. The use of lentiviral vector is expected to be widely used in PD research in the future due to its advantages in gene delivery.

     

Rhabdomyosarcoma of the Breast：A Clinicopathologic Study and Review of the Literature

Background  Rhabdomyosarcoma (RMS) is an uncommon malignancy of the breast. The aim of this study was to summarize its clinicopathologic features and biological behavior.

Methods  Five primary or secondary breast RMSs were collected. Their clinicopathological characteristics and all published literature about breast RMS were reviewed. Immunohistochemical study of desmin, myogenic differentiation 1 (MyoD1), myogenin, leukocyte common antigen (LCA), vimentin, cytokeratin (AE1/AE3), E-cadherin, neuron specific enolase (NSE), CD99, chorioallantoic membrane 5.2 (CAM5.2) and epithelial membrane antigen (EMA) expression were performed.

Results  The five patients were all female with ages ranging from 16 to 46 years old (mean, 30 years). Three were metastatic breast RMSs, two embryonal and one solid variant alveolar, with the primary tumor sites the right labium majus, left nasal meatus and nasopharynx, respectively. The other two, one embryonal and one alveolar, were primaries. Grossly, the surgical specimens revealed round or oval, well-demarcated but nonencapsulated masses. Their cut surfaces consisted of homogeneous grayish yellow or white tissue. Microscopically, most tumor cells were poorly differentiated small round, oval or small polygons with eosinophilic cytoplasm. All cases were positive for vimentin, desmin, MyoD1 and myogenin. One embryonal RMS also had a few cells with perinuclear staining of AE1/AE3. The other markers were negative.

Conclusions  Although primary or metastatic RMS in breast was almost confined to young adolescent females, our cases suggested that it can also happen to the middle-aged women. Embryonal RMS has a certain metastatic potential. MyoD1 and myogenin are two useful markers when making differential diagnosis. Axillary lymph node status and age may play a role in the prognosis of primary breast RMS patients.

     

Reversal of multidrug resistance in renal cell carcinoma by short hairpin RNA targeting MDR1 gene

Background  Over-expression of P-glycoprotein (P-gp), encoded by the MDR1 gene, confers multidrug resistance (MDR) in renal cell carcinoma (RCC) and is a major reason for unsuccessful chemotherapy. This study aimed to determine the effct of RNA interference (RNAi) on the reversal of MDR in human RCC.

Methods  We designed and selected one short hairpin RNA (shRNA) targeting MDR1 gene, which is stably expressed from integrated plasmid and transfected by lentivirus fluid in human RCC A498 cell.

Results  The MDR1-targeted RNAi resulted in decreased MDR1 gene mRNA level (P <0.001), almost abolished P-gp expression and reversed MDR to different chemotherapy drugs in the RCC A498 cell line.

Conclusion  MDR could be reversed by RNAi in human RCC A498 cell line, which may be used for clinical application in future.

     

Effect of pcDNA3.1- vascular endothelial growth factor 165 recombined vector on vascular buds in rabbit vertebral cartilage endplate

Background  This study aimed to investigate the effect of pcDNA3.1-vascular endothelial growth factor (VEGF)165 vector on vertebral cartilage endplate vascular buds and intervertebral discs.

Methods  Rabbits were randomly assigned to the control and experimental groups with 10 in each. In the experimental group, we anesthetized the rabbits and exposed the front vertebral body. Using the mark of the longitudinal ossature of the front vertebral body of the lumbar vertebrae, we advanced a needle at the central point of the front fourth and fifth lumbar intervertebral discs and injected 20 µl pcDNA3.1-VEGF165. Similarly, in the control group, we injected 20 µl pcDNA3.1. At 4 and 8 weeks post-injection, we examined the changes of the vertebral cartilage endplate using X-ray radiograph, histology, and scanning electron microscopy.

Results  The vertebral cartilage endplate calcification and degeneration in the experimental group were less than those in the control group at 8 weeks post-operation. The average number and diameter of vascular buds obviously increased in the experimental group at 4 and 8 weeks post-operation. The number of vascular buds and the diameter in the region of the inner annulus increased when compared to those in the area near the nucleus pulposus.

Conclusions  The pcDNA3.1-VEGF165 plasmid can increase the average number and diameter of vascular buds and decelerate intervertebral disc degeneration.

     

Transitional cell carcinoma associated with aristolochic acid nephropathy: most common cancer in chronic hemodialysis patients in China

Background  The research of cancer in patients on hemodialysis (HD) in China has not been reported. The aim of this study was to investigate the clinical and histological features and outcomes of cancer in Chinese HD patients.

Methods  The study subjects were 49 cancer patients (1.4%) out of 3448 end stage renal disease (ESRD) patients maintained on HD at China-Japan Friendship Hospital from October 1997 to July 2011.

Results  Urinary tract cancer (74%) was the most common followed by gastrointestinal tract cancer (12%), breast cancer (6%), lung cancer (4%), thyroid cancer (2%), and hematologic cancer (2%). Thirty-three patients (67%) had urinary tract transitional cell carcinoma (TCC) and 29 of them had aristolochic acid nephropathy (AAN) as underlying disease. Death occurred in eight patients out of 49, and the survival rate of HD patients with cancer was similar to those without cancer (P=0.120).

Conclusion  The urinary tract TCC is the most common cancer in HD patients with AAN in one of the centers of northern China.

     

Increased expression of serum gelsolin in patients with osteosarcoma.

Background  Identification of potential serum biomarkers of osteosarcoma to aid in its early diagnosis and in the discovery of possible therapeutic targets is an area of increasing interest.

Methods  Two-dimensional difference-in-gel electrophoresis was used to assess multiple serum samples in patients with osteosarcoma. In addition, differential expression of protein biomarkers was characterized in osteosarcoma serum by using matrix-assisted desorption/ionization time-of-flight mass spectrometry coupled with database interrogation. Serum samples from four individuals with osteosarcoma and four age- and sex-matched healthy control subjects were compared.

Results  Fifty-eight significant protein spot features in the osteosarcoma sera were found. These spot features were excised, digested with trypsin, and analyzed with mass spectrometry. Gelsolin was down-regulated only in osteosarcoma. Furthermore, Western blotting and enzyme linked immunosorbent assay (ELISA) confirmed decreased levels of gelsolin in the osteosarcoma serum samples.

Conclusions  These results indicated that gelsolin might have great potential as a biomarker of osteosarcoma and as a potential target for gene therapy.

     

Correlation between dynamic contrast-enhanced MRI and histopathology in the measurement of tumor and breast volume and their ratio in breast cancer patients: a prospective study

Background  Earlier studies have examined the association between the diameter of primary tumors measured by magnetic resonance imaging (MRI) and histopathology in breast cancer patients. However, the diameter does not completely describe the dimensions of the breast tumor or its volumetric proportion relative to the whole breast. The association between breast tumor volume/breast volume ratios measured by these two techniques has not been reported.

Methods  Seventy-three patients were recruited from female patients with primary breast tumors admitted to our center between January and December 2010. They were divided into two groups. Group A (n=46) underwent modified radical mastectomy (MRM), and Group B (n=27) underwent preoperative neoadjuvant chemotherapy before MRM. They were examined by dynamic-contrast enhanced MRI (DCE-MRI) to measure breast volumes (BVs), tumor volumes (TVs), and tumor volume/breast volume ratios (TV/BV). These measurements were compared with histopathology results after MRM, and the associations between MRI and pathology were analyzed by linear regression and Bland-Altman analysis.

Results   For Group A, the correlation coefficients for BVs, TVs, and TV/BV ratios measured by the two techniques were 0.938, 0.921, and 0.897 (all P <0.001), respectively. For Group B, the correlation coefficients for BVs, TVs, and TV/BV ratios were 0.936, 0.902, and 0.869 (all P <0.01), respectively. The results suggest statistically significant correlations between these parameters measured by the two techniques for both groups.

Conclusion  For these patients, BVs, TVs, and TV/BV ratios measured by DCE-MRI significantly correlated with those determined by histopathology.