To study the expression of X-linked inhibitor of apoptosis protein (XIAP) and cell apoptosis in vitro model of acute pancreatitis (AP), we carried out experiments to stimulate AR42J cell line with caerulein (10(-8) mol/L) for 12 hours, then collected cells at various time points (0 h, 4 h, 8 h, 12 h, and 24 h, respectively). We then observed the morphologic changes of AR42J cells with the stimulation of caerulein with electronic microscope. The gene expression of XIAP, caspase-3 and caspase-9 was detected using real-time fluorescence quantitative polymerase chain reaction (FQ-PCR), and the protein expression of XIAP was assessed by western blot. The activation of nuclear factor-kappa B (NF-kappaB) was measured by flow cytometry (FCM). With the stimulation of caerulein, the expression of XIAP and the NF-kappaB activation could first decrease and then increase, but the change of caspase-3 and caspase-9 expressions were opposite. XIAP may inhibit the cell apoptosis in rat pancreatic acinus AR42J cell lines at first with the stimulation of caerulein, then NF-kappaB can upgrade the expression of XIAP and increase the cell apoptosis.
Acinar Cells ; cytology ; metabolism ; Animals ; Apoptosis ; physiology ; Cell Line ; Ceruletide ; pharmacology ; NF-kappa B ; metabolism ; Pancreas ; cytology ; metabolism ; Pancreatitis ; metabolism ; Rats ; X-Linked Inhibitor of Apoptosis Protein ; genetics ; metabolism

OBJECTIVE: To investigate the expression of X-linked inhibitor of apoptosis protein (XIAP) and the apoptosis rate in cultured Hep-2 cells, and discuss their relationship. METHOD: Cultured Hep-2 cells were irradiated with 2, 4, 8 Gy gamma ray. Living inhibitor rate detected with MTT, apoptosis rate and fluorescence index number of XIAP in mRNA level by RT-PCR and in protein level by flow cytometry (FCM) were measured at 12th, 24th, 48th hours after radiation respectively. RESULT: After irradiation, the volume of adherent cells increased and the number of suspended cells increased accordingly. 48 hours after irradiation with 2, 4, 8 Gy, the living inhibitor rate of Hep2 cells were 3.24%, 8.29%, 13.53%, and apoptosis rate was 3.27%, 5.33%, 8.22%. The fluorescence index number of XIAP protein measured by FCM was 1.23, 1.46, 1.58 respectively. With the dosage of 4 Gy, at the 12th, 24th, 48th hours of irradiation, the apoptosis rate was 3.19%, 3.22%, 5.31%. The living inhibitor rate was direct correlation with apoptosis rate in radiated Hep-2 cells. The expression of XIAP increased quickly at the 24th hours after radiation but the apoptosis rate did not increased in the course. XIAP was no more increase at the 48th hours, while the apoptosis rate was significantly higher. Which indicated that Them two were negative correlation. CONCLUSION gamma-ray can inhibit the growth of Hep-2 cells. The irradiation dosage was direct correlation with living inhibitor rate. Apoptosis is the main death method of Hep-2 cells after irradiation. The over expression of XIAP maybe one reason which caused the delayed apoptosis after radiation.
Apoptosis ; radiation effects ; Carcinoma, Squamous Cell ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Gamma Rays ; Humans ; Laryngeal Neoplasms ; metabolism ; X-Linked Inhibitor of Apoptosis Protein ; metabolism

OBJECTIVETo investigate the effect of proteasome inhibitor bortezomib on proliferation, apoptosis of K562 cells and the expression of XIAP.

METHODSK562 cells were treated with bortezomib at different concentration. Cell proliferation was analyzed by WST-1 assay, cell apoptosis by flow cytometry and TUNEL, XIAP mRNA expression from 5 - 100 nmol/L by RT-PCR, and XIAP protein expression by SP immunohistochemistry.

RESULTSK562 cells were treated with bortezomib at different concentrations for 24 h respectively, the cells growth was significantly inhibited with inhibition rates from (13. 6 ± 0. 2)% to (81. 4 ± 0. 1)%, respectively, being markedly higher than that of control (1. 2 ± 0. 1)% (P < 0.05). IC(50) was 24. 6 nmol/L of bortezomib treated for 24 h. When K562 cells were treated with 30 nmol/L of bortezomib for 12 - 48 h, the inhibition rates were (29. 1 ± 0. 9)% to (59. 8 ± 1. 2)%, respectively, the differences being statistically significant (P < 0.05) between 12 h group and 24 h group, while there was no statistical difference between 24 h, 36 h and 48 h groups. K562 cells treated with 30 nmol/L bortezomib for 24 h showed nuclear condensation, nuclear margination, nuclear fragmentation, cytoplasmic vacuoles and a large number of apoptotic body formation. The apoptotic cells rate was 83. 67% in bortezomib treated group, and 2. 33% in untreated group (P < 0.05). The expression of XIAP mRNA was decreased in a dose-dependent manner, and the expression of its protein was down-regulated.

CONCLUSIONBortezomib can inhibit the proliferation of K562 cells, and induce apoptosis by down-regulating the expression of XIAP, providing the laboratory evidence for the targeted therapy in acute leukemia.

Apoptosis ; drug effects ; Boronic Acids ; pharmacology ; Bortezomib ; Cell Proliferation ; drug effects ; Humans ; K562 Cells ; Leukemia ; metabolism ; Pyrazines ; pharmacology ; X-Linked Inhibitor of Apoptosis Protein ; metabolism

OBJECTIVETo explore the effect of silence of Pin1 expression on hyperoxia-induced apoptosis in alveolar epithelial cells A549.

METHODSA549 cells were divided into four groups: control, hyperoxia, negative lentivirus and Pin1-shRNA hyperoxia. The hyperoxia group was exposed to a mixture of 95%O2 and 5%CO2 for 10 minutes. Then cells were cultured in a closed environment. After 24 hours, the changes of morphology were observed under an inverted microscope. Cell apoptosis was detected by flow cytometry (FCM). The expression of X-linked inhibitor of apoptosis protein (XIAP) and Caspase-9 were detected by immunohistochemistry. The production of reactive oxygen species (ROS) and cellular mitochondria membrane potential (△Ψm) were determined by fluorescence microscopy.

RESULTSUnder the inverted microscope, the A549 cells grew slowly and the changes in morphology of the cells were most obvious in the hyperoxia and negative lentivirus groups. The changes in morphology of A549 cells were obviously improved in the Pin1-shRNA hyperoxia group. The FCM results showed that the apoptosis rate of A549 cells increased, Caspase-9 expression increased, XIAP expression decreased, mitochondrial ROS production increased and mitochondrial membrane potential decreased in the hyperoxia and negative lentivirus groups compared with the control group (P<0.05). Compared with the hyperoxia and negative lentivirus groups, the apoptosis rate of A549 cells decreased, Caspase-9 expression decreased, XIAP expression increased, mitochondrial ROS production decreased and mitochondrial membrane potential increased in the Pin1-shRNA hyperoxia group (P<0.05), although the levels of the indexes did not reach to those of the control group.

CONCLUSIONSSilencing of Pin1 could suppress hyperoxia-induced apoptosis of A549 cells.

Apoptosis ; Caspase 9 ; genetics ; Humans ; Hyperoxia ; pathology ; Membrane Potential, Mitochondrial ; NIMA-Interacting Peptidylprolyl Isomerase ; Peptidylprolyl Isomerase ; physiology ; Reactive Oxygen Species ; metabolism ; X-Linked Inhibitor of Apoptosis Protein ; genetics

OBJECTIVETo investigate the expression of X-linked inhibitor of apoptosis protein (XIAP) in colorectal cancer tissues and investigate its correlation with the clinicopathological factors of the malignancy.

METHODSImmunohistochemistry and RT-PCR was employed to detect the expression of XIAP in 87 colorectal cancer tissues.

RESULTSXIAP mRNA expression was detected in 64.4% (56/87) of the colorectal cancer tissues, 49.4% (43/87) of the adjacent tissues, and in 11.4% (10/87) of the normal tissues, respectively. The cancer tissues showed significant greater positivity rate and higher expression level of XIAP mRNA than the adjacent and normal tissues. Immunohistochemistry also identified a significantly greater positivity rate for XIAP [70.1% (61/87)] in the colorectal cancer tissues. The pathological grade of the tumors was associated with the expression level of XIAP, whereas this association was not established between XIAP expression and the clinical stages, tumor position or lymph node metastasis.

CONCLUSIONXIAP may play an important role in the development of colorectal cancer, which might serve as a potentially useful tumor marker.

Adult ; Aged ; Colorectal Neoplasms ; metabolism ; pathology ; Female ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Neoplasm Staging ; RNA, Messenger ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; X-Linked Inhibitor of Apoptosis Protein ; metabolism

OBJECTIVE: To investigate the expression of X-chromosome-linked inhibitors of apoptosis (XIAP) XIAP in laryngeal squamous carcinomas and the relationship between the expression of XIAP and clinical biological behaviors. METHOD: Paraffin-embedded tissue specimens used for this study were obtained from 50 patients with laryngeal squamous carcinomas. The patients had received neither chemotherapy nor radiation therapy before tumor resection. Using immunohistochemical staining for the paraffin sections (SP methods), we examine the expression of XIAP protein in laryngeal squamous carcinomas and normal laryngeal tissues, investigate the connection of the XIAP expression with the clinicopathological parameters. RESULT: The expression of XIAP protein was observed mainly in the cytoplasm and nucleus. The staining color was dark brown. The expression of XIAP is remarkably higher in laryngeal squamous carcinomas than that in normal laryngeal tissue specimens. The statistical analysis revealed that in laryngeal squamous carcinomas XIAP expression had no relationship with the elements such as age, sex, smoking history, tumor site and lymph node metastases. However, there is significant correlation between XIAP expression and tumor clinical stage, T stage and pathological stage (P < 0.05). CONCLUSION XIAP is expressed higher in laryngeal squamous carcinomas than in normal laryngeal tissues. The level of XIAP expression is associated with tumor clinicopathological characteristics in laryngeal squamous carcinomas. While tumor growth and malignancy increased, the expression of XIAP was up-regulated in laryngeal squamous carcinomas. It may play a role of anti-apoptosis in the process of carcinogenesis and development in laryngeal squamous carcinomas.
Adult ; Aged ; Aged, 80 and over ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Female ; Humans ; Laryngeal Neoplasms ; metabolism ; pathology ; Male ; Middle Aged ; Neoplasm Staging ; X-Linked Inhibitor of Apoptosis Protein ; metabolism

At angle of cell apoptosis, the excessive less of hematopeitic cell apoptosis is a reason of hematopoietic cell accumulation. The Fas/FasL system as an important pathway inducing cell apoptosis participates in occurrence and development of leukemia. Leukemia cells generally are not sensitive or are resistant to Fas/FasL-mediated apoptosis, while it is one of important reasons resulting in immunoescape and unsensitivity of leukemia cells to chemotherapy. In recent years studies related to mechanisms of leukemia cell resistance to Fas/FasL-mediated apoptosis such as Fas and FasL mutation and expression abnormality, Fas signaling transduction pathway abnormality, and regulatory affect of apoptotic regulatory genes on Fas/FasL system, as well as strategies replying to antiapoptosis of leukemia cells including NF-kappab, XIAP, membrane receptor CD28 and matrix metalloproteinase 7 obtained some progresses. The above-mentioned issues were reviewed in this article.
Apoptosis ; physiology ; CD28 Antigens ; metabolism ; Fas Ligand Protein ; physiology ; Humans ; Leukemia ; pathology ; Matrix Metalloproteinase 7 ; metabolism ; NF-kappa B ; metabolism ; Tumor Cells, Cultured ; X-Linked Inhibitor of Apoptosis Protein ; metabolism ; fas Receptor ; physiology

OBJECTIVETo study the expression of the inhibitor of apoptosis (IAP) gene XIAP in prostate cancer and the relationship between its expression and its clinical stage or Gleason grade.

METHODSXIAP mRNA expression was detected by RT-PCR in three prostate cancer cell lines (PC-3, DU-145, LNCaP), neoplastic prostate tissues and normal prostate tissues. Immunohistochemical SP method was used to examine the expression of XIAP protein in 56 neoplastic prostate tissue specimens.

RESULTSXIAP gene was not expressed in normal prostate tissues, but highly expressed in prostate cancer cell lines PC-3, DU-145, LNCaP. Thirty of the 56 (53.6%) tumor samples were positive XIAP protein, and only 12 (21.5%) paratumor samples were positive XIAP protein (P < 0.01), XIAP positivity not correlated with tumor stage or Gleason grade (P > 0.05).

CONCLUSIONXIAP may be involved in the development of prostate cancer and play an important role in human prostate carcinogenesis. It is likely to be used as a target of prostate cancer therapy.

Aged ; Aged, 80 and over ; Cell Line, Tumor ; Humans ; Immunohistochemistry ; Male ; Neoplasm Staging ; Prostatic Neoplasms ; metabolism ; pathology ; Reverse Transcriptase Polymerase Chain Reaction ; X-Linked Inhibitor of Apoptosis Protein ; biosynthesis ; genetics

The aim of study was to explore the effects of NF-kappaB inhibitor Bay 11 - 7082 on Fas/FasL system and Fas-mediated apoptosis in HL-60 cells. The mRNA and protein expression levels of Fas, FasL and XIAP after treatment with Bay 11 - 7082 were detected by RT-PCR and FCM respectively. The level of sFasL was detected by ELISA before and after treatment with Bay 11 - 7082; apoptosis was detected by FCM before and after treatment with Bay 11 - 7082. The results showed that after treating HL-60 cells with Bay 11 - 7082, the mRNA and protein levels of FasL and XIAP were lower than that of controls, the difference was significant by statistic analysis (p < 0.05). Neither the mRNA and protein levels of Fas, nor the level of sFasL changed significantly (p > 0.05). Apoptotic rate of HL-60 cells treated with Bay 11 - 7082 was significantly higher as compared with controls (p < 0.05). It is concluded that Bay 11 - 7082 can enhance Fas-mediated apoptosis in HL-60 cells by down-regulation of FasL and XIAP levels.
Apoptosis ; drug effects ; Down-Regulation ; Fas Ligand Protein ; physiology ; Gene Expression Regulation, Leukemic ; HL-60 Cells ; Humans ; NF-kappa B ; antagonists & inhibitors ; Nitriles ; pharmacology ; RNA, Messenger ; metabolism ; Sulfones ; pharmacology ; X-Linked Inhibitor of Apoptosis Protein ; metabolism ; fas Receptor ; metabolism

Amino Acid Sequence ; Base Sequence ; Child ; Flow Cytometry ; methods ; Genes, X-Linked ; Hematopoietic Stem Cell Transplantation ; Humans ; Lymphocytes ; metabolism ; Lymphohistiocytosis, Hemophagocytic ; diagnosis ; genetics ; therapy ; Lymphoproliferative Disorders ; diagnosis ; genetics ; therapy ; Mutation ; Transplantation, Homologous ; X-Linked Inhibitor of Apoptosis Protein ; deficiency ; genetics ; metabolism