Culture supernatants of breast cancer cell line MDA-MB-231 treated with parthenolide inhibit the proliferation, migration, and lumen formation capacity of human umbilical vein endothelial cells

Background  Parthenolide has been tested for anti-tumor activities, such as anti-proliferation and pro-apoptosis in recent studies. However, little is known about its role in the process of tumor angiogenesis. This study aims to investigate the effects and potential mechanisms of parthenolide on the proliferation, migration and lumen formation capacity of human umbilical vein endothelial cells.

Methods  Different concentrations of parthenolide were applied to the human breast cancer cell line MDA-MB-231 cells. After 24-hour incubation, the culture supernatants were harvested and used to treat human umbilical vein endothelial cells for 24 hours. Then an inverted fluorescence phase contrast microscope was used to evaluate the human umbilical vein endothelial cells. The secretion of vascular endothelial growth factor (VEGF), interleukin (IL)-8 and matrix metalloproteinases (MMP)-9 in the culture supernatant of the MDA-MB-231 cells was then measured with enzyme-linked immunosorbent assay (ELISA) assays.

Results  Suppression of proliferation, migration, and the lumen formation capacity of human umbilical vein endothelial cells was observed in the presence of the culture supernatants from the breast cancer cell line treated with different concentrations of parthenolide. Parthenolide decreased the levels of the angiogenic factors MMP-9, VEGF, and IL-8 secreted by the MDA-MB-231 cells.

Conclusions  Parthenolide may suppress angiogenesis through decreasing angiogenic factors secreted by breast cancer cells to interfere with the proliferation, migration and lumen-like structure formation of endothelial cells, thereby inhibiting tumor growth. It is a promising potential anti-angiogenic drug.

     

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.

     

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.

     

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.

     

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.

     

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.

     

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.

     

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.

     

Minimally invasive transforaminal lumbar interbody fusion aided with computer-assisted spinal navigation system combined with electromyography monitoring

Background  Minimally invasive techniques are gaining wide-spread application in lumbar fusion surgery, because they may have advantage over conventional open surgery in approach-related morbidity. This research was aimed to evaluate the safety and accuracy of the techniques of minimally invasive transforaminal lumbar interbody fusion by using a computer-assisted spinal navigation system combined with electromyography monitoring.

Methods  Sixteen patients underwent minimally invasive transforaminal lumbar interbody fusion. A computer-assisted spinal navigation system and electromyography were used for guiding pedicle screw placement. The operative duration, blood loss, complications, and fluoroscopic time were recorded. Clinical outcome was assessed by Visual Analog Scale and Oswestry Disability Index. Radiographic images were obtained to evaluate the accuracy of pedicle screw placement and fusion rates.

Results  The Visual Analog Scale and Oswestry Disability Index scores were vastly improved postoperatively. A total of 64 pedicle screws were implanted and three were regarded as misplacement by post-operative CT scan. Three screw trajectories were adjusted according to intra-operative stimulus-evoked electromyography monitoring. The average fluoroscopy time in each patient was 31.8 seconds, which equals to 7.9 seconds per pedicle screw. No patients had instrument related neurological complications, infection, implant failure or revision. Successful fusion was found in all patients.

Conclusions  The combination of navigation system and real-time electromyography monitoring can make the minimally invasive operation more safe and accurate while decreasing radiation exposure time of the medical staff and patient and minimizing the chance and the degree of the pedicle screw misplacement.

     

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.

     

非肿瘤细胞凋亡引起肿瘤机体血清细胞色素C增高

Background  Neuroblastoma (NB) is one of the most common malignant solid tumors of childhood. It is still not clear whether the apoptosis of tumor cells or the non-tumor cells contributes to the increase of concentration of cytochrome c (Cyt c) in the serum of the cancer patients. The aim of this research was to identify the source of the Cyt c in the serum when the tumor grows up by subcutaneous inoculation of human NB cells into nude mice.

Methods  We subcutaneously inoculated human NB cells (KP-N-NS) into nude mice and collected the sera of tumor-bearing mice (n=14) and control mice (n=25) 4 weeks later in order to screen for and identify differentially expressed proteins in the serum. Differentially expressed proteins in the serum were screened by surface-enhanced laser desorption/ionization-time-of-flight (SELDI-TOF) mass spectrometry.

Results  The relative intensity of a protein having a mass-to-charge ratio (m/z) of 11 609 was 3338.37±3410.85 in the tumor group and 59.84±40.74 in the control group, indicating that the expression level of this protein in the tumor group was 55.8 times higher than that in the control group. Serum proteins were separated and purified by high-performance liquid chromatography (HPLC). Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was performed to produce peptide mass fingerprints (PMFs). Spectrum analysis and a database search revealed that the highly expressed protein (m/z=11 605.4) from the serum of tumor-bearing mice was the mouse Cyt c.

Conclusions  Increased concentration of Cyt c in the serum of tumor-bearing nude mice might be partially attributed to the secretion of this protein by non-tumor cells.

     

Tissue-engineered calcium phosphate cement in rabbit femoral condylar bone defects

Background  Calcium phosphate cement (CPC) is a favorable bone-graft substitute, with excellent biocompatibility and osteoconductivity. However, its reduced osteoinductive ability may limit the utility of CPC. To increase its osteoinductive potential, this study aimed to prepare tissue-engineered CPC and evaluate its use in the repair of bone defects. The fate of transplanted seed cells in vivo was observed at the same time.

Methods  Tissue-engineered CPC was prepared by seeding CPC with encapsulated bone mesenchymal stem cells (BMSCs) expressing recombinant human bone morphogenetic protein-2 (rhBMP-2) and green fluorescent protein (GFP). Tissue-engineered CPC and pure CPC were implanted into rabbit femoral condyle bone defects respectively. Twelve weeks later, radiographs, morphological observations, histomorphometrical evaluations, and in vivo tracing were performed.

Results  The radiographs revealed better absorption and faster new bone formation for tissue-engineered CPC than pure CPC. Morphological and histomorphometrical evaluations indicated that tissue-engineered CPC separated into numerous small blocks, with active absorption and reconstruction noted, whereas the residual CPC area was larger in the group treated with pure CPC. In the tissue-engineered CPC group, in vivo tracing revealed numerous cells expressing both GFP and rhBMP-2 that were distributed in the medullar cavity and on the surface of bony trabeculae.

Conclusion  Tissue-engineered CPC can effectively repair bone defects, with allogenic seeded cells able to grow and differentiate in vivo after transplantation.

     

Role of microRNA-181a in the apoptosis of tubular epithelial cell induced by cisplatin 

Background  Cisplatin (DDP) is one of most effective and most commonly used therapeutic agent in treating tumors, it can accumulate in the kidney and lead to acute renal failure. MicroRNA-181a can induce cell apoptosis by suppressing the expression of Bcl-2 family. In the present study, we investigated the role of microRNA-181a in the apoptosis of tubular epithelial cell induced by DDP.

Methods  HK-2 cells were cultured, transfected with microRNA-181a inhibitor for 48 hours, and stimulated with 50 µmol/L cisplatin for 24 hours. MicroRNA-181a expression was analyzed by real time PCR, and cell apoptosis was detected by flow cytometry. Moreover, Bcl-2 and Bcl-2-associated X protein (Bax) expression were measured by Western blotting.

Results  MicroRNA-181a expression significantly down-regulated in cells transfected with microRNA-181a inhibitor, compared with that in untransfectd cells (21.19±2.01 vs. 38.87±1.97, P <0.05). Cell apoptosis induced by DDP significantly decreased in cells transfected with MicroRNA-181a inhibitor. Compared with DDP treated cells alone, Bcl-2 expression strikingly was up-regulated and Bax expression was down-regulated in cells transfected with microRNA-181a inhibitor.

Conclusion  One pathway of DDP induces apoptosis of tubular epithelial cell by suppressing Bcl-2 expression is achieved by regulating the target gene of MicroRNA-181a.

     

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.

     

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.

     

Hyper-CVAD chemotherapy or autologous stem cell transplantation in patients with peripheral T cell lymphomas: a single centre report

Background  Peripheral T-cell lymphoma (PTCL) is generally characterized by poor prognosis after conventional chemotherapy. The place for high-dose chemotherapy and autologous stem cell transplantation (ASCT) in these patients is still not clear. In this study, we presented the outcomes of PTCL patients followed these treatments in our centre.

Methods  We retrospectively analyzed the outcomes of 39 patients with PTCL received the two treatments between 1999 and 2010.

Results  The 3-year overall survival (OS) of 61.9% and 3-year progression free survival (PFS) of 35.7% were observed in the 39 patient. Twenty-one patients received Hyper-CVAD chemotherapy with 3-year OS of 46.2% and 3-year PFS of 27.9%. Eighteen patients received ASCT with 3-year OS of 70.3% and 3-year PFS of 44.2%. Further analysis revealed that patients with elevated lactate dehydrogenase, at least 2 international prognostic index (IPI) points, and extranodal involvement had a poorer outcome compared with the control group.

Conclusion  These findings might suggest that Hyper-CVAD chemotherapy and ASCT could offer a durable survival benefit for patients with aggressive PTCL.