Predicting the subcellular location of apoptosis proteins based on recurrence quantification analysis and the Hilbert Huang transform

Apoptosis proteins play an important role in the development and homeostasis of an organism. The elucidation of the subcellular locations and functions of these proteins is helpful for understanding the mechanism of programmed cell death. In this paper, the recurrent quantification analysis, Hilbert-Huang transform methods, the maximum relevance and minimum redundancy method and support vector machine are used to predict the subcellular location of apoptosis proteins. The validation of the jackknife test suggests that the proposed method can improve the prediction accuracy of the subcellular location of apoptosis proteins and its application may be promising in other fields.

Bcl-2 over-expression and activation of protein kinase C suppress the Trail-induced apoptosis in Jurkat T cells

Trail, a tumor necrosis factor-related apoptosis-inducing ligand, is a novel potent endogenous activator of the cell death pathway through the activation of cell surface death receptors Trail-R1 and Trail-R2. Its role, like FasL in activation-induced cell death (AICD), has been demonstrated in immune system. However the mechanism of Trail induced apoptosis remains unclear. In this report, the recombinant Trail protein was expressed and purified. The apoptosis-inducing activity and the regulation mechanism of recombinant Trail on Jurkat T cells were explored in vitro. Trypan blue exclusion assay demonstrated that the recombinant Trail protein actively killed Jurkat T cells in a dose-dependent manner. Trail-induced apoptosis in Jurkat T cells were remarkably reduced by Bcl-2 over expression in Bcl-2 gene transfected cells. Treatment with PMA (phorbol 12-myristate 13-acetate), a PKC activator, suppressed Trail-induced apoptosis in Jurkat T cells. The inhibition of apoptosis by PMA was abolished by pretreatment with Bis, a PKC inhibitor. Taken together, it was suggested that Bcl-2 over-expression and PMA activated PKC actively down-regulated the Trail-mediated apoptosis in Jurkat T cell.

Killing effect of TNF-related apoptosis inducing ligand regulated by tetracycline on gastric cancer cell line NCI-N87

AIM: To clone the cDNA fragment of human TRAIL (TNF-related apoptosis inducing ligand) into a tetracycline-regulated gene expression system, the RevTet-On system, transduce expression vectors into a gastric carcinoma cell line-NCI-N87 and examine the effects of controlled expression of TRAIL in vitro on the gastric carcinoma cells. METHODS: The full-length cDNA of TRAIL was inserted into a vector under the control of the tetracycline-responsive element (TRE) to obtain the plasmid pRevTRE-TRAIL, which was transfected into a packaging cell line PT67. In addition, vector pRev-Tet On and pRevTRE were also transfected into PT67 separately. After hygromycin and G418 selection, the viral titer was determined. The medium containing retroviral vectors was collected and used to transduce a gastric carcinoma cell line NCI-N87. The resulting cell line NCI-N87-Tet On TRE-TRAIL and a control cell line, NCI-N87 Tet On-TRE, were established. TRAIL expression in the cell line was induced by incubating cells with doxycycline (Dox), which is a tetracycline analogue. The killing effect on gastric carcinoma cells was analyzed after induction. RESULTS: The recombinant plasmid pRev-TRE-TRAIL was constructed. After hygromycin or G418 selection, the producer cell lines PT67-TRE, PT67-TRE-TRAIL and PT67-Tet On were obtained,with titers of about 10(8)CFU.L(-1). By transducing NCI-N87 cells with retroviral vectors from these cell lines, stable cell lines NCI-N87-Tet-On TRE-TRAIL (NN3T) and control cell line NCI-N87-Tet-On-TRE (NN2T) were established. The growth curves of the selected cell lines were the same with the wild type NCI-N87. When Dox was added, cell death was obvious in the test groups (29%-77%), whereas no difference was observed in control and wild type cell lines. With the addition of a medium from the test group, human leukemia cell line Jurkat was activated till death (83%), indicating the secretion of active TRAIL proteins from the test cells to the medium. CONCLUSION: With the use of the RevTet-On system, a regulated expression system for TRAIL was constructed. Using this system, the selected killing effect of TRAIL on gastric carcinoma cell line NCI-N87 could be observed.

SMAC exhibits anti-tumor effects in ECA109 cells by regulating expression of inhibitor of apoptosis protein family

BACKGROUND The poor prognosis and rising incidence of esophageal cancer highlight the need for improved therapeutics that are essential prior to treatment.LCL161 is an SMAC(second mitochondrial activator of caspases)mimic and inhibitor of apoptosis protein(IAP)antagonist which exhibits anti-tumor effects and improves the chemical sensitivity of many cancers.AIM To ascertain the effects and mechanisms of the SMAC analog LCL161 on esophageal cancer cells.METHODS MTT assay and TUNEL assay were used to detect cell proliferation and apoptosis,respectively.Western blot analysis was used to study the molecular mechanisms of LCL161-induced death of ECA109 cells.RESULTS LCL161 decreased ECA109 cell proliferation in dose-and time-dependent manner and induced apoptosis of ECA109 cells in a dose-dependent manner.Also,LCL161 induced a significant decrease in the expression of the XIAP and significant increase in the expression of Caspase-3.In addition,Bax increased significantly with increasing concentrations of LCL161,and the relative expression of Bax was significantly different between groups.CONCLUSION These findings support the hypothesis that LCL161 can inhibit proliferation and induce apoptosis in esophageal cancer cells by regulating the expression of IAP family members,suggesting that it has potential to be an effective treatment for esophageal squamous cell carcinoma.

Regulatory Effects of X-linked Inhibitor of Apoptosis Protein and Pro-apoptotic Protein Smac on Apoptosis Resistance to Chemotherapy in Pancreatic Cancer Cells~*

Objective： To investigate the relation of X-linked inhibitor of apoptosis （XIAP） and second mitochondria-derived activator of caspase （Smac） signaling pathway to chemoresistance in human pancreatic cancer Panc-1 and BXPC-3 cells. Methods： Apoptosis and the changes of XIAP expression in permeabilized cells induced by cisplatin and 5-fluorouracil （FU） were measured by flow cytometry. The cytosolic expression of XIAP, Smac and caspase-3 was detected by Western blot. A recombinant plasmid vector pEGFP-N1/Smac was constructed and transfected into of Pancol cells. The effect of cytosolic overexpression of Smac on apoptosis of Panc-1 cells was evaluated by flow cytometry. Results： Panc-1 was more resistant to cisplatin or 5-FU induced apoptosis than BXPC-3. Western blot revealed that chemoresistant Panc-1 highly expressed XIAP, and increased cytosolic expression of Smac might be responsible for the marked down-regulation of XIAP in chemo-sensitive BXPC-3 cells after exposure to cisplatin or 5-FU. Furthermore, cytosolic overexpression of Smac could significantly down-regulate the levels of XIAP and promote the activity of caspase-3, as well as sensitize Panc-1 cells to anticancer drug-induced apoptosis. Conclusion： Anticancer drug-induced apoptosis requires mitochondrial release of Smac and downregulation of XIAP, which may be an important determinant of chemo-sensitivity in pancreatic cancer cells. Up-regulation of cytosolic expression of Smac may act as an effective modifying signal to overcome apoptosis resistance to chemotherapy in pancreatic cancer cells.

Targeting X-linked inhibitor of apoptosis protein inhibits pancreatic cancer cell growth through p-Akt depletion

AIM: To determine whether lentivirus-mediated shRNA targeting the X-linked inhibitor of apoptosis protein (XIAP) gene could be exploited in the treatment of pancreatic cancer. METHODS: Human pancreatic cancer cells Panc-1, Mia-paca2, Bxpc-3 and SW1990, infected with lentivirus, were analyzed by real-time polymerase chain reaction (PCR). Western blotting was used to examine XIAP protein levels, survivin and p-Akt to confirm the result of real-time PCR and determine the possible mechanism. The 3-(4,5-cimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT) assay was used to measure IC50 to determine chemosensitivity to the chemotherapeutic drugs 5-fluorouracil (5-FU) and gemcitabine. A colony assay, MTT assay and a tumorigenicity experiment were used to study cell proliferation in vitro and in vivo . Caspase-3/7 activity, 4',6-diamidino-2-phenylindole-staining and flow cytometric measurements were used to study apoptosis in SW1990 cells. RESULTS: XIAP proteins were found to be differen- tially expressed among pancreatic cancer cell lines Panc-1, Mia-paca2, Bxpc-3 and SW1990. Data of real-time PCR and Western blotting showed that XIAP was reduced persistently and markedly by lentivirus-mediated shRNA. Downregulation of XIAP by transfection with XIAP shRNA resulted in decreased p-Akt expression. XIAP shRNA also inhibited the growth of pancreatic cancer cells in vitro and in vivo , enhanced drug-induced apoptosis and increased chemosensitivity to 5-FU and gemcitabine. Results also suggest that inhibition of XIAP and subsequent p-Akt depletion may have an anti-tumor effect through attenuating the ability of cancer cells to survive. CONCLUSION: Lentivirus-mediated gene therapy is an attractive strategy in the treatment of pancreatic cancer and justifies the use of lentivirus in pancreatic cancer gene therapy studies.

Baculoviral inhibitor of apoptosis protein repeatcontaining protein 3 delays early Wallerian degeneration after sciatic nerve injury

Wallerian degeneration is a complex biological process that occurs after nerve injury,and involves nerve degeneration and regeneration.Schwann cells play a crucial role in the cellular and molecular events of Wallerian degeneration of the peripheral nervous system.However,Wallerian degeneration regulating nerve injury and repair remains largely unknown,especially the early response.We have previously reported some key regulators of Wallerian degeneration after sciatic nerve injury.Baculoviral inhibitor of apoptosis protein repeat-containing protein 3(BIRC3)is an important factor that regulates apoptosis-inhibiting protein.In this study,we established rat models of right sciatic nerve injury.In vitro Schwann cell models were also established and subjected to gene transfection to inhibit and overexpress BIRC3.The data indicated that BIRC3 expression was significantly up-regulated after sciatic nerve injury.Both BIRC3 upregulation and downregulation affected the migration,proliferation and apoptosis of Schwan cells and affected the expression of related factors through activating c-fos and ERK signal pathway.Inhibition of BIRC3 delayed early Wallerian degeneration through inhibiting the apoptosis of Schwann cells after sciatic nerve injury.These findings suggest that BIRC3 plays an important role in peripheral nerve injury repair and regeneration.The study was approved by the Institutional Animal Care and Use Committee of Nantong University,China(approval No.2019-nsfc004)on March 1,2019.

Expression of second mitochondria-derived activator of caspases, X-linked inhibitor of apoptosis protein, and caspase-3 in pituitary adenomas

Studies concerning correlations between pituitary adenomas and cell apoptosis have mainly focused on upstream apoptosis signaling, but seldom on downstream mediators. In the present study, second mitochondria-derived activator of caspases （Smac）, X-linked inhibitor of apoptosis protein （XIAP）, and caspase-3 protein were qualitatively analyzed using immunohistochemistry, and quantified by western blot. Smac, XIAP, and caspase-3 mRNA expressions were detected by reverse transcription-PCR. Results showed that XIAP protein and mRNA expressions were greater in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. However, Smac and caspase-3 protein and mRNA expressions were lower in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. In the invasive pituitary adenomas, Smac expression was positively correlated with caspase-3 protein and mRNA expression （Protein： r = 0.55, P 0.01; mRNA： r = 0.50, P 0.01）. Smac and caspase-3 expressions were negatively correlated with XIAP protein and mRNA expression （Protein： r = -0.56, -0.64, P 0.01; mRNA： r = -0.69, -0.67, P 0.01）. However, no significant differences in correlation among Smac, XIAP, and caspase-3 were detectable in noninvasive pituitary adenomas. These data indicated that high expression of XIAP and low expression of Smac and caspase-3 suppressed cell apoptosis and led to enhanced invasiveness of pituitary adenomas. Thus, Smac, XIAP, and caspase-3 may be useful markers in determining the invasive behavior of pituitary adenomas.

Effect of senescence marker protein 30 on the proliferation and apoptosis of human lens epithelial cells SRA01/04

AIM： To study the effect of senescence marker protein 30（SMP30） on the proliferation and apoptosis of human lens epithelial cell（HLEC） SRA01/04.METHODS： SMP30 overexpression（OE） and knock down（KD） type cell lines were cultivated by using two groups regucalcin（RGN; SMP30） lentiviral vectors（LVRGN, LV-RGN-RNAi） and the respective negative control virus infect SRA01/04 cells. Western blot and real-time quantitative polymerase chain reaction（q-PCR） analysis were used to determine RGN overexpression and knock down efficiency. We use cell counting kit-8（CCK8） assay to measure cell viability and 5-bromodeoxyuridine（Brd U） assay to test cell proliferation. Cell cycle was measured by PI FACS assay and cell apoptosis was tested by Annexin V-APC assay through flow cytometry. We use Western blot to measure the content of caspase-3 in SRA01/04.RESULTS： We used PCR and Western blot techniques to determine the successful transfection of SMP30 OE and KD SRA01/04 cell lines. By CCK8, Brdu and PI FACS cell cycle assay, it was found that the SMP30 OE group promoted cell proliferation（P〈0.05） compared with the control group, and the KD group inhibited cell proliferation（P〈0.05）. The results of Annexin V-APC signal staining detection indicated that compared with respective control group, the cell apoptosis rate was higher in KD group（P〈0.05） but lower in OE group（P〈0.01）. The expression of caspase-3 was down-regulated in OE group through Western blot assay and up-regulated in KD group compared with respective control group. CONCLUSION： Proliferation of SRA01/04 was promoted by SMP30 OE and apoptosis was suppressed. Increasing the expression of SMP30 may protect HLEC SRA01/04 against apoptosis in cataract.

c-Jun N-terminal kinase is required for thermotherapyinduced apoptosis in human gastric cancer cells

AIM:To investigate the role of c-Jun N-terminal kinase(JNK) in thermotherapy-induced apoptosis in human gastric cancer SGC-7901 cells.METHODS:Human gastric cancer SGC-7901 cells were cultured in vitro.Following thermotherapy at 43 ℃ for 0,0.5,1,2 or 3 h,the cells were cultured for a further 24 h with or without the JNK specific inhibitor,SP600125 for 2 h.Apoptosis was evaluated by immunohistochemistry [terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)] and flow cytometry(Annexin vs propidium iodide).Cell proliferation was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide.The production of p-JNK,Bcl-2,Bax and caspase-3 proteins was evaluated by Western blotting.The expression of JNK at mRNA level was determined by reverse transcription polymerase chain reaction.RESULTS:The proliferation of gastric carcinoma SGC-7901 cells was significantly inhibited following thermotherapy,and was 32.7%,30.6%,43.8% and 52.9% at 0.5,1,2 and 3 h post-thermotherapy,respectively.Flow cytometry analysis revealed an increased population of SGC790l cells in G0/G1 phase,but a reduced population in S phase following thermotherapy for 1 or 2 h,compared to untreated cells(P < 0.05).The increased number of SGC-790l cells in G0/G1 phase was consistent with induced apoptosis(flow cytometry) following thermotherapy for 0.5,1,2 or 3 h,compared to the untreated group(46.5% ± 0.23%,39.9% ± 0.53%,56.6% ± 0.35% and 50.4% ± 0.29% vs 7.3% ± 0.10%,P < 0.01),respectively.This was supported by the TUNEL assay(48.2% ± 0.4%,40.1% ± 0.2%,61.2% ± 0.29% and 52.0% ± 0.42% vs 12.2% ± 0.22%,P < 0.01) respectively.More importantly,the expression of p-JNK protein and JNK mRNA levels were significantly higher at 0.5 h than at 0 h post-treatment(P < 0.01),and peaked at 2 h.A similar pattern was detected for Bax and caspase-3 proteins.Bcl-2 increased at 0.5 h,peaked at 1 h,and then decreased.Furthermore,the JNK specific inhibitor,SP600125,suppressed p-JNK,Bax and caspase-3 at the protein level in SGC790l cells following thermotherapy,compared to mock-inhibitor treatment,which was in line with the decreased rate of apoptosis.The expression of Bcl-2 was consistent with thermotherapy alone.CONCLUSION:Thermotherapy induced apoptosis in gastric cancer cells by promoting p-JNK at the mRNA and protein levels,and up-regulated the expression of Bax and caspase-3 proteins.Bcl-2 may play a protective role during thermotherapy.Activation of JNK via the Bax-caspase-3 pathway may be important in thermotherapy-induced apoptosis in gastric cancer cells.

Knockdown of HMGB1 improves apoptosis and suppresses proliferation and invasion of glioma cells

Background： Effective methods for managing patients with solitary pulmonary nodules（SPNs） depend critically on the predictive probability of malignancy.Methods： Between July 2009 and June 2011, data on gender, age, cancer history, tumor familial history, smoking status, tumor location, nodule size, spiculation, calcification, the tumor border, and the final pathological diagnosis were collected retrospectively from 154 surgical patients with an SPN measuring 3-30 mm. Each final diagnosis was compared with the probability calculated by three predicted models—the Mayo, VA, and Peking University（PU） models. The accuracy of each model was assessed using area under the receiver operating characteristics（ROC） and calibration curves.Results： The area under the ROC curve of the PU model [0.800; 95% confidence interval（CI）： 0.708-0.891] was higher than that of the Mayo model（0.753; 95% CI： 0.650-0.857） or VA model（0.728; 95% CI： 0.623-0.833）; however, this finding was not statistically significant. To varying degrees, calibration curves showed that all three models overestimated malignancy.Conclusions： The three predicted models have similar accuracy for prediction of SPN malignancy, although the accuracy is not sufficient. For Chinese patients, the PU model may has greater predictive power.Background： Here, we introduced our short experience on the application of a new CUSA Excel ultrasonic aspiration system, which was provided by Integra Lifesciences corporation, in skull base meningiomas resection.Methods： Ten patients with anterior, middle skull base and sphenoid ridge meningioma were operated using the CUSA Excel ultrasonic aspiration system at the Neurosurgery Department of Shanghai Huashan Hospital from August 2014 to October 2014. There were six male and four female patients, aged from 38 to 61 years old（the mean age was 48.5 years old）. Five cases with tumor located at anterior skull base, three cases with tumor on middle skull base, and two cases with tumor on sphenoid ridge.Results： All the patents received total resection of meningiomas with the help of this new tool, and the critical brain vessels and nerves were preserved during operations. All the patients recovered well after operation.Conclusions： This new CUSA Excel ultrasonic aspiration system has the advantage of preserving vital brain arteries and cranial nerves during skull base meningioma resection, which is very important for skull base tumor operations. This key step would ensure a well prognosis for patients. We hope the neurosurgeons would benefit from this kind of technique.Background： The purposes of this study were to explore the effects of high mobility group protein box 1（HMGB1） gene on the growth, proliferation, apoptosis, invasion, and metastasis of glioma cells, with an attempt to provide potential therapeutic targets for the treatment of glioma. Methods： The expressions of HMGB1 in glioma cells（U251, U-87 MG and LN-18） and one control cell line（SVG p12） were detected by real time PCR and Western blotting, respectively. Then, the effects of HMGB1 on the biological behaviors of glioma cells were detected： the expression of HMGB1 in human glioma cell lines U251 and U-87 MG were suppressed using RNAi technique, then the influences of HMGB1 on the viability, cycle, apoptosis, and invasion abilities of U251 and U-87 MG cells were analyzed using in a Transwell invasion chamber. Also, the effects of HMGB1 on the expressions of cyclin D1, Bax, Bcl-2, and MMP 9 were detected. Results： As shown by real-time PCR and Western blotting, the expression of HMGB1 significantly increased in glioma cells（U251, U-87 MG, and LN-18） in comparison with the control cell line（SVG p12）; the vitality, proliferation and invasive capabilities of U251 and U-87 MG cells in the HMGB1 siR NA-transfected group were significantly lower than those in the blank control group and negative control（NC） siR NA group（P〈0.05） but showed no significant difference between the blank control group and NC siR NA group. The percentage of apoptotic U251 and U-87 MG cells was significantly higher in the HMGB1 siR NA-transfected group than in the blank control group and NC siR NA group（P〈0.05） but was similar between the latter two groups. The HMGB1 siR NA-transfected group had significantly lower expression levels of Cyclin D1, Bcl-2, and MMP-9 protein in U251 and U-87 MG cells and significantly higher expression of Bax protein than in the blank control group and NC siR NA group（P〈0.05）; the expression profiles of cyclin D1, Bax, Bcl-2, and MMP 9 showed no significant change in both blank control group and NC siR NA group. Conclusions： HMGB1 gene may promote the proliferation and migration of glioma cells and suppress its effects of apoptosis. Inhibition of the expression of HMGB1 gene can suppress the proliferation and migration of glioma cells and promote their apoptosis. Our observations provided a new target for intervention and treatment of glioma.

THE EXPRESSION AND CLINICAL VALUE OF APOPTOSIS CONTROL GENE Bcl-2 AND Bax IN BREAST CANCER

Objective: To study the expression and clinical value of apoptosis control gene bcl-2 and bax in breast cancer. Methods: Protein bax and bcl-2 in 41 breast cancers obtained from operations in our hospital in 1996 were detected using ABC immunohistochemical stain assay and compared with 10 cases with normal breast tissues. Results: The positive rate of bax in normal breast tissue was 90% and in breast cancer was 59%, with a significant statistical difference between them (P<0.05), but there was no statistical difference in bcl-2 protein expression. Among the 41 breast cancer, the group with lymph node metastasis (21 cases) had obviously low bax expression (43%) and high bcl-2 expression (76%), showing significant difference to the group without lymph node metastasis (P<0.05). Conclusion: The antiapoptosis function of bcl-2 was stronger than bax in breast cancer. Protein bax and bcl-2 assay may be useful in understanding the biological behaviors of breast cancer.

Expression of X-linked Inhibitor of Apoptosis Protein and Its Effect on Chemotherapeutic Sensitivity of Bladder Carcinoma

The expression of X-linked inhibitor of apoptosis protein (XIAP) gene and its effect on chemotherapeutic sensitivity in bladder carcinoma was explored. By using immunohistochemistry, the expression of XIAP was detected in 47 bladder carcinomas and 5 normal bladder tissues. The XIAP gene was transfected into bladder cancer cell line T24 by liposome and the positive clone was screened by G418. Cellular XIAP mRNA level was detected by RT-PCR. Low-dose mitocycin C was administered to induce the apoptosis of T24 cells. The in vitro growth of bladder carcinoma cells was analyzed by MTT colorimetry, and the apoptosis rate was assayed by TUNEL methods. It was found XIAP was moderately expressed in bladder carcinomas with the the positive rate being 78.73% (37/47), but the positive rate was not correlated with carcinoma stages and grades (P<0.05). XIAP mRNA level in transfected T24 cells was significantly increased by 3.8 times as compared with that in the cells not transfected with XIAP. After treatment with low-dose mitomycin C (0.005 and 0.05 mg/mL), the growth rate in XIAP no-transfected control group was increased by (11.60±0.25)% and (16.51±0.87)% (P<0.05), and the apoptosis rate was decreased by (10.1±0.2)% and (11.9±0.2%) (P<0.05) respectively as compared with XIAP transfected group. It was concluded that XIAP was expressed in most of bladder carcimoma samples. Overexpression of XIAP in T24 could significantly reduce the MMC-induced apoptosis of bladder carcinoma, suggesting its effect on the chemothera- peutic sensitivity of T24 cells.

Expression of telomerase gene and apoptosis related genes in benign and malignant breast lesion

Objective:To analyse the expression of telomerase and apoptosis related protein,and explore the possible mechanism of breast cancer development.Methods:Immunohistochemistry method(SP)was used to detect the expression of hTERT,p53 and bcl-2 in the tissues of 48 cases of human breast cancer and 42 cases of benign lesions in breast.Results: The positive rates of expression of hTERT,p53 and bcl-2 in breast cancer were 87.50%,56.25%and 54.17%,respectively. Compared with the groups of adjacent noncancerous and benign lesions,there was a significant difference among three types of tissues(P<0.05).The positive rates of expression of p53 and bcl-2 in the group with positive expression of hTERT were 64.28%and 61.90%,respectively,and their difference was significant compared with the negative group(P<0.05). Conclusion:There is a correlation between the activation of telomerases and p53 gene mutation in the development of breast cancer,and they are perhaps relation to the down regulation of bcl-2.

Association of the Cellular Apoptosis Susceptibility Protein with HBV Infection in Hepatocellular Carcinoma

Objective The cellular apoptosis susceptibility(CAS) protein plays a regulatory role in the induction of cell death in tumor cells. The objective of this study was to investigate the association of the expression of CAS protein with HBV infection in the development of HCC. Methods The expression level of CAS was measured with immunohistochemistry. The occurrence of HBs Ag, HBe Ag and HBV DNA in HCC were concurrently examined with immunohistochemistry and in situ hybridization, respectively. Results The results showed that the CAS protein was detected in 86%(43/50), 70%(7/10), 15%(3/20) and none(0/20) of livers from patients with HCC, cholangiocarcinoma, cirrhosis and hepatitis, respectively. Furthermore, the level of CAS protein was higher in poorly differentiated tumors than moderately or well differentiated HCC. Interestingly, the CAS was stained significantly stronger in HBV-infected HCC than in non-HBV infected tissues(P < 0.01). Conclusions The expression of CAS is facilitated by HBV infection in HCC, suggesting that CAS might be a prognostic marker and a putative therapeutic target for HCC.

The prediction of recurrence and survival of patients with Dukes’ B colorectal cancer after curative resection with immunohistochemical detection of Survivin and Livin expressions

Objective: To detect the expressions of Survivin and Livin in Dukes’ B colorectal cancer tissues and analyze the prognosis after curative resection. Methods: The expressions of Survivin and Livin were evaluated immunohistochemically in Dukes’ B colorectal cancer specimens from 81 patients after curative resection of the tumor. Their correlations to clinical characters and survival were also explored. Results: The positive rates of Survivin and Livin in colorectal cancer tissues were significantly higher than those in normal colorectal tissues (58.0% vs. 16.7% and 45.7% vs. 8.3% respectively, P < 0.05). The expressions of Survivin and Livin were not related to gender, tumor site, primary size, T stage, pathologic category, and degree of differentiation (P > 0.05), and no relationship was found between the expressions of Survivin and Livin (P > 0.05). The expression rate of Survivin in patients older than 50 years was higher than that in patients younger than 50 years (70.6% vs. 36.7%, P < 0.05). Both Survivin and Livin were related to recurrence and/or metastasis (P = 0.02 and P = 0.001, respectively), and shorter survival (P = 0.039 and P = 0.001, respectively). Cox multivariate analysis showed T4 and positive Livin expression were independent prognostic factors (P = 0.002 and P = 0.047, respectively). Conclusion: Survivin and Livin are over-expressed in Dukes’ B colorectal cancer tissues and are positively related to recurrence and/or metastasis and poor prognosis after curative resection of the tumor.

Expression of Livin in tissues of lung cancer and its correlation with the expression of caspase-3

Objective： To study the expressions of two isoforms of Livin in tissues of lung cancer and their relations to histological types and chemotherapy, and to study their correlations to the expression of caspase-3 as well. Methods： Expressions of Livin isoforms a, 13 and caspase-3 were detected by reverse transcription polymerase chain reaction （RT-PCR） assay in lung cancer tissues as well as in controls. Results： Livin isoforms a and ~ were expressed in 12 of 27, and 19 of 27 lung cancer tissues respectively, much more than those in lung para-cancereus [both were （0/6）] or benign disease lung tissues （0/12, 1/12; P 〈 0.01 and P 〈 0.01 ）. Moreover, they were detected in 7/14, 9/14 lung adenocarcinomas and 4/12, 9/12 squamocallular and large call carcinomas, respectively, and both showed expressions in one small cell carcinoma. The levels of these two isoforms in lung cancer were significantly higher than those in controls by Gel imaging system （P 〈 0.05 and P 〈 0.05）, the former was higher in adenocarcinoma than that in squamocellular carcinoma （P 〈 0.05）, while the latter was the same in both （P 〉 0.05）. Meanwhile, the levels of caspase-3 in lung cancer were significantly lower than those in controls, and it was suggested to be negatively associated with either each of two isoforms or their sum （P 〈 0.05, P 〈 0.01 and P 〈 0.01）. Two isoforms of Livin expression seemed to increase＇after chemotherapy but not related to clinical stages （P 〉 0.05）. Conclusion： Two isoforms of Livin are differently expressed in different histological types of lung cancer and may contribute to corresponding cancerous development; the levels of Livin are negatively associated with those of caspase-3, this may be due to the fact that Livin could resist against apoptosis; high expression of Livin seems to be related to chemotherapy but not clinical stages.

Obstructive sleep apnea aggravates neuroinflammation and pyroptosis in early brain injury following subarachnoid hemorrhage via ASC/HIF-1α pathway

Obstructive sleep apnea can worsen the prognosis of subarachnoid hemorrhage.Howeve r,the underlying mechanism remains unclear.In this study,we established a mouse model of subarachnoid hemorrhage using the endovascular perforation method and exposed the mice to intermittent hypoxia for 8 hours daily for 2 consecutive days to simulate sleep apnea.We found that sleep apnea aggravated brain edema,increased hippocampal neuron apoptosis,and worsened neurological function in this mouse model of subarachnoid hemorrhage.Then,we established an in vitro HT-22 cell model of hemin-induced subarachnoid hemorrhage/intermittent hypoxia and found that the cells died,and lactate dehydrogenase release increased,after 48 hours.We further investigated the underlying mechanism and found that sleep apnea increased the expression of hippocampal neuroinflammatory factors interleukin-1β,interleukin-18,inte rleukin-6,nuclear factorκB,pyro ptosis-related protein caspase-1,pro-caspase-1,and NLRP3,promoted the prolife ration of astrocytes,and increased the expression of hypoxia-inducible factor 1αand apoptosis-associated speck-like protein containing a CARD,which are the key proteins in the hypoxia-inducible factor 1α/apoptosis-associated speck-like protein containing a CARD signaling pathway.We also found that knockdown of hypoxia-inducible factor 1αexpression in vitro greatly reduced the damage to HY22 cells.These findings suggest that sleep apnea aggravates early brain injury after subarachnoid hemorrhage by aggravating neuroinflammation and pyroptosis,at least in part through the hypoxia-inducible factor 1α/apoptosis-associated speck-like protein containing a CARD signaling pathway.

Gene transfection mediated by polyethyleneiminepolyethylene glycol nanocarrier prevents cisplatininduced spiral ganglion cell damage

Polyethyleneimine-polyethylene glycol （PEI-PEG）, a novel nanocarrier, has been used for trans- fection and gene therapy in a variety of cells. In our previous study, we successfully carried out PEI-PEG-mediated gene transfer in spiral ganglion cells. It remains unclear whether PEI-PEG could be used for gene therapy with X-linked inhibitor of apoptosis protein （XIAP） in the inner ear. In the present study, we performed PEI-PEG-mediated XIAP gene transfection in the cochlea of Sprague-Dawley rats, via scala tympani fenestration, before daily cisplatin injections. Audito- ry brainstem reflex tests demonstrated the protective effects of XIAP gene therapy on auditory function. Immunohistochemical staining revealed XIAP protein expression in the cytoplasm of cells in the spiral ganglion, the organ of Corti and the stria vascularis. Reverse transcription-PCR detected high levels of XIAP mRNA expression in the cochlea. The present findings suggest that PEI-PEG nanocarrier-mediated XIAP gene transfection results in XIAP expression in the cochlea, prevents damage to cochlear spiral ganglion cells, and protects hearing.

Transfection of gene Livin α/β into A549 cells and separate effect on the cell growth

Objective:To express two Livin isoforms (Livin α & β genes) with transfection techniques in A549 cell line respectively in order to observe their effect on growth of cell line. Methods:Two eukaryotic expression vectors of Livin, pcDNA3.1-Livin α & β, were transfected into A549 cell line by electroporation. Then G418-resistant clones were screened. RT-PCR, Northern blot and immunofluorescence cytochemistry were used to detect Livin α & β expression level in the transfected cells. Finally, observation of cell morphology, growth curve assay and colony formation analysis were performed to explore the effect of Livin on growth of the cells. Results:Livin α & β were expressed in transfected A549 cells, and induced a faster cell growth, shorter doubling time and stronger cell colony forming ability, yet had no morphology change.Conclusion:Both isoforms can accelerate the growth of A549 cells, indicating a close relationship between Livin expression and the genesis and development of lung cancer. The expression of Livin α & β in A549 cells provides basis for further study of their different biological functions of anti-apoptosis and of their role in lung cancer cell resistance to radiotherapy and chemotherapy.