Baculovirus Inhibitor Of Apoptosis Protein Research Articles

An Insight into Survivin in Relevance to Hematological, Biochemical and Genetic Characteristics in Tobacco Chewers with Oral Squamous Cell Carcinoma.

Survivin is an inhibitor of apoptosis protein (IAP), encoded by the Baculoviral IAP Repeat Containing 5 (BIRC5) gene located on q arm (25.3) on chromosome 17. It is expressed in various human cancers and involved in tumor resistance to radiation and chemotherapy. The genetic analysis of the BIRC5 gene and its protein survivin levels in buccal tissue related to oral squamous cell carcinoma (OSCC) in South Indian tobacco chewers has not been studied. Hence, the study was designed to quantify survivin in buccal tissue and its association with pretreatment hematological parameters and to analyze the BIRC5 gene sequence. In a single centric case control study, buccal tissue survivin levels were measured by ELISA. A total of 189 study subjects were categorized into Group 1 (n = 63) habitual tobacco chewers with OSCC, Group 2 (n = 63) habitual tobacco chewers without OSCC, and Group 3 (n = 63) healthy subjects as control. Retrospective hematological data were collected from Group 1 subjects and statistically analyzed. The BIRC5 gene was sequenced and data were analyzed using a bioinformatics tool. Survivin protein mean ± SD in Group 1 was (1670.9 ± 796.21 pg/mL), in Group 2 it was (1096.02 ± 346.17 pg/mL), and in Group 3 it was (397.5 ± 96.1 pg/mL) with significance (p < 0.001). Survivin levels showed significance with cut-off levels of absolute monocyte count (AMC), neutrophil/lymphocyte ratio (NLR), and lymphocyte/monocyte ratio (LMR) at (p = 0.001). The unique variants found only in OSCC patients were T → G in the promoter region, G → C in exon 3, C → A, A → G, G → T, T → G, A → C, G → A in exon 4, C → A, G → T, G → C in the exon 5 region. The tissue survivin level increased in OSCC patients compared to controls; pretreatment AMC, LMR, and NLR may serve as add-on markers along with survivin to measure the progression of OSCC. Unique mutations in the promoter and exons 3-5 were observed in sequence analysis and were associated with survivin concentrations.

Structures of BIRC6-client complexes provide a mechanism of SMAC-mediated release of caspases.

Tight regulation of apoptosis is essential for metazoan development and prevents diseases such as cancer and neurodegeneration. Caspase activation is central to apoptosis, and inhibitor of apoptosis proteins (IAPs) are the principal actors that restrain caspase activity and are therefore attractive therapeutic targets. IAPs, in turn, are regulated by mitochondria-derived proapoptotic factors such as SMAC and HTRA2. Through a series of cryo-electron microscopy structures of full-length human baculoviral IAP repeat-containing protein 6 (BIRC6) bound to SMAC, caspases, and HTRA2, we provide a molecular understanding for BIRC6-mediated caspase inhibition and its release by SMAC. The architecture of BIRC6, together with near-irreversible binding of SMAC, elucidates how the IAP inhibitor SMAC can effectively control a processive ubiquitin ligase to respond to apoptotic stimuli.

New Class of Benzodiazepinone Derivatives as Pro-Death Agents Targeting BIR Domains in Cancer Cells.

Inhibitor of Apoptosis Proteins (IAPs) are validated targets for cancer therapy, and the deregulation of their activities within the NF-κB pathway correlates with chemoresistance events, even after treatment with IAPs-antagonists in the clinic (Smac-mimetics). The molecule FC2 was identified as a NF-κB pathway modulator in MDA-MB-231 adenocarcinoma cancer cells after virtual screening of the Chembridge library against the Baculoviral IAP Repeat 1 (BIR1) domain of cIAP2 and XIAP. An improved cytotoxic effect is observed when FC2 is combined with Smac-mimetics or with the cytokine Tumor Necrosis Factor (TNF). Here, we propose a library of 22 derivatives of FC2, whose scaffold was rationally modified starting from the position identified as R1. The cytotoxic effect of FC2 derivatives was evaluated in MDA-MB-231 and binding to the cIAP2- and XIAP-BIR1 domains was assessed in fluorescence-based techniques and virtual docking. Among 22 derivatives, 4m and 4p display improved efficacy/potency in MDA-MB-231 cells and low micromolar binding affinity vs the target proteins. Two additional candidates (4b and 4u) display promising cytotoxic effects in combination with TNF, suggesting the connection between this class of molecules and the NF-κB pathway. These results provide the rationale for further FC2 modifications and the design of novel IAP-targeting candidates supporting known therapies.

Krüppel-like factor 5 promotes the progression of oral squamous cell carcinoma via the baculoviral IAP repeat containing 5 gene.

BackgroundKrüppel-like factor 5 (KLF5) is highly expressed in a variety of tumors, and our study aimed to investigate the role of KLF5 in oral squamous cell carcinoma (OSCC).MethodsTo explore the differential expression of KLF5, next-generation sequencing (NGS) and further analyses were conducted in paired premalignant and tumor tissues and adjacent normal mucosa. We then analyzed the mRNA expression data from The Cancer Genome Atlas (TCGA) and performed gene set enrichment analysis (GSEA) to predict the function of KLF5. Small interfering RNA (siRNA) targeting KLF5 was used to knock down its expression in cells and further evaluate the changes in cell apoptosis, proliferation, and migration. We predicted whether baculoviral inhibitor of apoptosis protein (IAP) repeat containing 5 (BIRC5) was the potential target gene of KLF5 via the NCBI and JASPAR databases. Furthermore, we analyzed BIRC5 expression after KLF5 knockdown and explored its function in athymic BALB/c nude mice.ResultsKLF5 expression in clinical samples gradually increased from normal mucosa tissues to premalignant and then to OSCC tissues. Analysis of TCGA data and GSEA also suggested that KLF5 was expressed at higher levels in OSCC and involved apoptosis and the protein 53 (P53), transforming growth factor-β (TGF-β), and wingless/integrated (Wnt) signaling pathways. Cell apoptosis was promoted, whereas proliferation and migration were inhibited after KLF5 knockdown. Furthermore, we found KLF5 transcription binding sites on the BIRC5 promoter and BIRC5 expression was inhibited after suppressing KLF5 in vitro and in vivo.ConclusionsOur findings indicate that KLF5 promotes the development of OSCC via BIRC5, and could be a potential diagnostic and therapeutic target for OSCC.

Inhibition of BIRC2 sensitizes α7-HPV related cervical squamous cell carcinoma to chemotherapy (215)

<b>Objectives:</b> α7-Human papillomavirus (HPV)-related cervical squamous cell carcinoma (SCC) treated with radiotherapy, or concurrent chemoradiation (RT/CCRT) is associated with poor prognosis. We aimed to discover the underlying relevant biomarkers. <b>Methods:</b> We compared the genomic profiles of α7-HPV-related cervical SCC (2001-2014 cohort) with different responses to radiotherapy or concurrent chemoradiation by microRNA profiling (miR4.0 array) and human transcriptome array 2.0, then verified by a real-time reverse-transcriptase quantitative polymerase chain reaction in order to discover predictive biomarkers. <b>Results:</b> We found significantly lower expression of miR143-3p in tumors with treatment failure (<i>p</i> = 0.0309), while one of the miR143-3p targets baculoviral inhibitor of apoptosis protein (IAP) repeat-containing 2 <i>(BIRC2)</i> mRNA expression (<i>p</i> = 0.0261) and BIRC2 protein levels (<i>p</i> = 0.0023) were significantly higher than those without treatment failure. Moreover, we showed that miR-143-3p sensitizes chemotherapy via targeting <i>BIRC2.</i> Besides, a combination of <i>BIRC2</i> inhibitor (LCL161) and topotecan exerted synergistic effects on cancer cells and animal tumor models. With a pooled cohort of α7-HPV (including mixed infections with coexisting non-α7-HPV(s))-related cervical SCC treated between 1993 and 2014, high <i>BIRC2</i> expression was associated with significantly worse outcome (cancer-specific survival, HR: 1.42; <i>p</i> = 0.008, progression-free survival, HR: 1.64; <i>p</i> = 0.005). <b>Conclusions:</b> These results suggest <i>BIRC2</i> is a novel prognostic factor and therapeutic target for α7-HPV-related cervical SCC.Fig. 1

Inhibitory effects of LOXL2 knockdown on cellular functions of liver cancer stem cells.

BackgroundLysyl oxidase-like 2 (LOXL2) plays a role in tumor microenvironment formation and metastasis of hepatocellular carcinoma (HCC), which has a high mortality burden. Liver cancer stem cells (LCSCs) are related with the major malignant phenotypes of HCC. The function of LOXL2 in regulation of LCSCs remains unknown.MethodsCD133+HepG2 and CD133+Hep3B cells were sorted by fluorescence-activated cell sorting (FACS) from two human hepatoblastoma cell lines. Spheroid formation, apoptosis, cell cycle, as well as transwell assays were performed upon LOXL2 knockdown in CD133+HepG2 and CD133+Hep3B cells. Protein and mRNA levels were quantified by Western blotting, immunofluorescence and reverse transcription-PCR (RT-PCR).ResultsKnockdown of LOXL2 decreased spheroid formation, migration and invasion (P<0.05), also induced apoptosis (P<0.05) and cell cycle arrest (P<0.05) in CD133+HepG2 and CD133+Hep3B cells. Knockdown of LOXL2 effectively inhibited expression of the anti-apoptosis proteins baculoviral inhibitor of apoptosis protein (IAP) repeat-containing 3 (BIRC3) and murine double minute 2 (MDM2) (P<0.01), as well as autophagy marker microtubule-associated protein 1 light chain 3 B (LC3B) and autophagy gene ATG5 in CD133+HepG2 and CD133+Hep3B cells (P<0.01).ConclusionsThe results revealed that LOXL2 inhibition could reduce the proliferation and expansion of LCSCs, making LOXL2 inhibitors an attractive and novel therapeutic strategy of HCC.

Snail Promotes Cancer Cell Proliferation via Its Interaction with the BIRC3.

Snail is implicated in tumour growth and metastasis and is up-regulated in various human tumours. Although the role of Snails in epithelial-mesenchymal transition, which is particularly important in cancer metastasis, is well known, how they regulate tumour growth is poorly described. In this study, the possible molecular mechanisms of Snail in tumour growth were explored. Baculoviral inhibitor of apoptosis protein (IAP) repeat-containing protein 3 (BIRC3), a co-activator of cell proliferation during tumourigenesis, was identified as a Snail-binding protein via a yeast two-hybrid system. Since BIRC3 is important for cell survival, the effect of BIRC3 binding partner Snail on cell survival was investigated in ovarian cancer cell lines. Results revealed that Bax expression was activated, while the expression levels of anti-apoptotic proteins were markedly decreased by small interfering RNA (siRNA) specific for Snail (siSnail). siSnail, the binding partner of siBIRC3, activated the tumour suppressor function of p53 by promoting p53 protein stability. Conversely, BIRC3 could interact with Snail, for this reason, the possibility of BIRC3 involvement in EMT was investigated. BIRC3 overexpression resulted in a decreased expression of the epithelial marker and an increased expression of the mesenchymal markers. siSnail or siBIRC3 reduced the mRNA levels of matrix metalloproteinase (MMP)-2 and MMP-9. These results provide evidence that Snail promotes cell proliferation by interacting with BIRC3 and that BIRC3 might be involved in EMT via binding to Snail in ovarian cancer cells. Therefore, our results suggested the novel relevance of BIRC3, the binding partner of Snail, in ovarian cancer development.

Toxoplasma gondii infection induces cell apoptosis via multiple pathways revealed by transcriptome analysis

Toxoplasma gondii is a worldwide parasite that can infect almost all kinds of mammals and cause fatal toxoplasmosis in immunocompromised patients. Apoptosis is one of the principal strategies of host cells to clear pathogens and maintain organismal homeostasis, but the mechanism of cell apoptosis induced by T. gondii remains obscure. To explore the apoptosis influenced by T. gondii, Vero cells infected or uninfected with the parasite were subjected to apoptosis detection and subsequent dual RNA sequencing (RNA-seq). Using high-throughput Illumina sequencing and bioinformatics analysis, we found that pro-apoptosis genes such as DNA damage-inducible transcript 3 (DDIT3), growth arrest and DNA damage-inducible α (GADD45A), caspase-3 (CASP3), and high-temperature requirement protease A2 (HtrA2) were upregulated, and anti-apoptosis genes such as poly(adenosine diphosphate (ADP)-ribose) polymerase family member 3 (PARP3), B-cell lymphoma 2 (Bcl-2), and baculoviral inhibitor of apoptosis protein (IAP) repeat containing 5 (BIRC5) were downregulated. Besides, tumor necrosis factor (TNF) receptor-associated factor 1 (TRAF1), TRAF2, TNF receptor superfamily member 10b (TNFRSF10b), disabled homolog 2 (DAB2)‍-interacting protein (DAB2IP), and inositol 1,4,5-trisphosphate receptor type 3 (ITPR3) were enriched in the upstream of TNF, TNF-related apoptosis-inducing ligand (TRAIL), and endoplasmic reticulum (ER) stress pathways, and TRAIL-receptor 2 (TRAIL-R2) was regarded as an important membrane receptor influenced by T. gondii that had not been previously considered. In conclusion, the T. gondii RH strain could promote and mediate apoptosis through multiple pathways mentioned above in Vero cells. Our findings improve the understanding of the T. gondii infection process through providing new insights into the related cellular apoptosis mechanisms.

CircBIRC6 contributes to the development of non-small cell lung cancer via regulating microRNA-217/amyloid beta precursor protein binding protein 2 axis.

Background:Circular RNAs (circRNAs) are considered to be important regulators in cancer biology. In this study, we focused on the effect of circRNA baculoviral inhibitor of apoptosis protein (IAP) repeat containing 6 (circBIRC6) on non-small cell lung cancer (NSCLC) progression.Methods:The NSCLC and adjacent non-tumor tissues were collected at Shanghai Ninth People's Hospital. Quantitative real-time polymerase chain reaction was conducted for assessing the levels of circBIRC6, amyloid beta precursor protein binding protein 2 (APPBP2) messenger RNA (mRNA), baculoviral IAP repeat containing 6 mRNA (BIRC6), and microRNA-217 (miR-217). Western blot assay was adopted for measuring the protein levels of APPBP2, E-cadherin, N-cadherin, and vimentin. Colony formation assay, transwell assay, and flow cytometry analysis were utilized for evaluating cell colony formation, metastasis, and apoptosis. Dualluciferase reporter assay and RNA immunoprecipitation assay were carried out to determine the interaction between miR-217 and circBIRC6 and APPBP2 in NSCLC tissues. The murine xenograft model assay was used to investigate the function of circBIRC6 in tumor formation in vivo. Differences were analyzed via Student's t test or one-way analysis of variance. Pearson's correlation coefficient analysis was used to analyze linear correlation.Results:CircBIRC6 was overexpressed in NSCLC tissues and cells. Knockdown of circBIRC6 repressed the colony formation and metastasis and facilitated apoptosis of NSCLC cells in vitro and restrained tumorigenesis in vivo. Mechanically, circBIRC6 functioned as miR-217 sponge to promote APPBP2 expression in NSCLC cells. MiR-217 inhibition rescued circBIRC6 knockdown-mediated effects on NSCLC cell colony formation, metastasis, and apoptosis. Overexpression of miR-217 inhibited the malignant phenotypes of NSCLC cells, while the effects were abrogated by elevating APPBP2.Conclusion:CircBIRC6 aggravated NSCLC cell progression by elevating APPBP2 via sponging miR-217, which might provide a fresh perspective on NSCLC therapy.

CircCAMSAP1 promotes non-small cell lung cancer proliferation and inhibits cell apoptosis by sponging miR-1182 and regulating BIRC5

ABSTRACT Recently, various studies have suggested that circular RNAs (circRNAs) are ubiquitous in various malignant events, including non-small cell lung cancer (NSCLC) and are closely related to cell proliferation and apoptosis. Unfortunately, the molecular functions involved in this action still have little overlap. Therefore, this study aimed to identify a novel circCAMSAP1 role in NSCLC. Overexpression of circCAMSAP1 has been demonstrated in NSCLC lung tissues and cell lines. Sequencing and RNase R experiments were planned to determine whether circCAMSAP1 is looped and exists in NSCLC. We also found that downregulated circCAMSAP1 repressed cell proliferation and increased apoptosis of NSCLC cells in vitro and suppressed xenograft tumor growth in vivo. Furthermore, a luciferase assay revealed that circCAMSAP1 could regulate baculoviral inhibitor of apoptosis protein (IAP) repeat containing 5 (BIRC5, also known as survivin) expression by directly binding to miR-1182. However, BIRC5 without 3ʹ untranslated regions (3ʹUTR) could reverse the influence of downregulated circCAMSAP1 on proliferation and apoptosis in NSCLC. Together, our findings reveal a novel mechanism by which the circCAMSAP1/miR-1182/BIRC5 axis promotes NSCLC progression.

LINC00511 Knockdown Suppresses Resistance to Cisplatin in Lung Adenocarcinoma by Interacting with miR-182-3p and BIRC5.

We studied the role of long intergenic non-protein coding RNA 00,511 (LINC00511) in lung adenocarcinoma (LUAD), with a specific focus on acquired chemoresistance. LINC00511 expression was higher in responders to cisplatin (DDP, another name for cisplantin) than non-responders, in A549/DDP cells than in parental A549 cells and normal human bronchial epithelial cells (16HBE). LINC00511 knockdown decreased the half maximal inhibitory concentration (IC50) value, suppressed A549/DDP cell viability, but induced apoptosis. LINC00511 bound with miR-182 and increased the expression of baculoviral inhibitor of apoptosis protein (IAP) repeat containing 5 (BIRC5). BIRC5 knockdown mimicked the effects of LINC00511 knockdown on the IC50 value, A549/DDP cell viability, and apoptosis. BIRC5 overexpression negated the effects of LINC00511 knockdown on A549/DDP cells. In vivo, LINC00511 knockdown attenuated the tumorigenesis of A549/DDP cells after DDP injection. These results provide a novel LINC00511/miR-182/BIRC5 paradigm to explain the mechanism of acquired DDP resistance.

A short report on the tumor suppressor role of BIRC7 in pancreatic cancer

&lt;p&gt;Pancreatic cancer (PC) is accepted to be an aggressive malignancy among all type of cancers due to its poor prognosis and high cancer-led mortality ratio mostly affecting male community in older age. Multiple genes are involved in PC initiation, progression and metastasis including K-RAS, CDKN2A, p53, SMAD4. Baculoviral IAP repeat containing 7 (BIRC7) commonly known as Livin, an inhibitor of apoptosis protein (IAP) involved in the inhibition of cell death via apoptosis by preventing caspase activity through various approaches. The biological role of BIRC7 was previously identified in multiple cancers but ill investigated in PC. In this study, we investigate the function role of BIRC7 in PC. Multiple phenotypic tests including wound healing assay, CCK8 assay, trans-well assay and colony formation assay was run to rule out BIRC7 gene effect on PC genesis. We for the first time indicated that, overexpression of BIRC7 significantly reduced the proliferation, development, progression and metastasis of PANC-1 cell &lt;em&gt;in vitro&lt;/em&gt;. Therefore, we anticipated that BIRC7 gene is a suppressor gene and might be a suitable candidate gene for therapeutic purposes in PC.&lt;/p&gt;

Unraveling novel survivin mRNA transcripts in cancer cells using an in-house developed targeted high-throughput sequencing approach

The human baculoviral IAP repeat containing 5 (BIRC5), also known as survivin, is a conserved member of the inhibitor of apoptosis protein (IAPs) family, which is normally expressed during embryonic and fetal development. Although the expression levels of survivin are low in terminally differentiated cells and/or tissues, they can be found notably increased in certain pathological conditions including malignant tumors. Conventional cloning and sequencing techniques have already confirmed that alternative splicing events of the survivin pre-mRNA result in five distinct alternative transcript variants. In the present study, however, we implemented an innovative, in-house developed, targeted DNA-seq assay to identify novel survivin alternative transcript variants with increased depth and coverage that high-throughput sequencing approaches offer. Bioinformatics analysis of the derived NGS datasets unveiled several novel splice junctions between annotated exons of survivin gene as well as the existence of a novel exon of 117 nt, spanning between the annotated exons 3 and 3B. Validation of the NGS findings with PCR-based assays, using variant-specific primers, led to the identification of fourteen novel survivin alternative splice variants (BIRC5 v.4 - v.17), which demonstrate wide expression profiles in a broad established panel of human cell lines. Although the presented novel findings provide a crystal-clear overview of the survivin mRNAs that are actually generated from the pre-mRNA, future studies should focus on the impending necessity of characterizing the biological function of all novel alternative transcript variants as well as the putative protein isoforms. Such studies will further contribute to our understanding of how the balance between survivin isoforms regulate malignant cell proliferation and apoptosis, providing novel diagnostic, prognostic and predictive biomarkers as well as therapeutic targets.

665 Associations of BIRC2/3/5 copy number gains with clinicopathological features of acral melanomas in Taiwan

Anti-apoptotic molecules can protect melanoma cells from apoptosis, thus enhancing their aggression. One of the factors responsible for the difficulties in engaging the apoptotic cascade efficiently in melanoma is the up-regulation of conserved inhibitor of apoptosis proteins (IAPs). All IAPs share up to three conserved zinc-binding baculoviral IAP repeats domains. The best described members are cIAP1, cIAP2, X-linked IAP, and surviving, which are encoded by Baculovirus inhibitor of apoptosis repeat containing genes (BIRC2, BIRC3, BIRC4, and BIRC5). These proteins are associated with chemoresistance and poor outcome in many cancer types. Acral melanoma is the most common subtype of melanoma in Asians. Our previous report found that frequencies of NRAS/KRAS mutations, altered cell cycle regulation, BIRC2/3/5 copy number gain, and amplification of receptor tyrosine kinase genes were significantly enriched in acral melanomas. In addition, BIRC2/3 copy number gain was only detected in the acral melanomas, and acral melanomas had significantly more BIRC2/3/5 copy number gain than the cutaneous melanomas. Most of BIRC2/3/5 copy number gains were detected in acral melanomas developed in stress-bearing areas. Moreover, the melanomas with BIRC2/3/5 gain were associated with ulceration and greater Breslow thickness. Our further analysis found that cell cycle alteration, BIRC2/3/5 copy number gain, and lymph node status were significant prognostic factors in 45 acral melanoma in a univariate analysis. In a multivariate analysis, altered cell cycle and lymph node status remained the most crucial independent prognostic factors in acral melanomas. We identified BIRC2/3/5 might be a critical determinant of survival in the acral melanoma patients.

Expression of Murine CD80 by Herpes Simplex Virus 1 in Place of Latency-Associated Transcript (LAT) Can Compensate for Latency Reactivation and Anti-apoptotic Functions of LAT.

High rates of wild-type (WT) herpes simplex virus 1 (HSV-1) latency reactivation depend on the anti-apoptotic activities of latency-associated transcript (LAT). Replacing LAT with the baculovirus inhibitor of apoptosis protein (cpIAP) or cellular FLIP (FLICE-like inhibitory protein) gene restored the WT latency reactivation phenotype to that of a LAT-minus [LAT(-)] virus, while similar recombinant viruses expressing interleukin-4 (IL-4) or interferon gamma (IFN-γ) did not. However, HSV-1 recombinant virus expressing cpIAP did not restore all LAT functions. Recently, we reported that a similar recombinant virus expressing CD80 in place of LAT had higher latency reactivation than a LAT-null virus. The present study was designed to determine if this CD80-expressing recombinant virus can restore all LAT functions as observed with WT virus. Our results suggest that overexpression of CD80 fully rescues LAT function in latency reactivation, apoptosis, and immune exhaustion, suggesting that LAT and CD80 have multiple overlapping functions.IMPORTANCE Recurring ocular infections caused by HSV-1 can cause corneal scarring and blindness. A major function of the HSV-1 latency-associated transcript (LAT) is to establish high levels of latency and reactivation, thus contributing to the development of eye disease. Here, we show that the host CD80 T cell costimulatory molecule functions similarly to LAT and can restore the ability of LAT to establish latency, reactivation, and immune exhaustion as well as induce the expression of caspase 3, caspase 8, caspase 9, and Bcl2. Our results suggest that, in contrast to several other previously tested genes, CD80-expressing virus can completely compensate for all known and tested LAT functions.

Phosphorylation Modulates Survivin Function in Behcet's Disease.

Purpose: Survivin is critical for proliferation, maturation, homeostasis and differentiation of effector and memory lymphocytes. In this study the baculoviral inhibitors of apoptosis proteins (IAPs) repeat containing 5 (BIRC5) mRNA, survivin, and phosphorylated survivin expression were evaluated in peripheral blood mononuclear cells (PBMCs), and plasma of patients with Behcet’s disease (BD). Methods: In this study, 26 Iranian Azari patients diagnosed with BD and 30 healthy controls were recruited. Total RNA was extracted from PBMCs. The expression level of survivin was measured by quantitative real-time polymerase chain reaction (PCR). Survivin plasma levels were measured using survivin Enzyme-linked immunosorbent assays. Also, western blotting analysis was performed to measure phosphorylated-survivin and survivin levels in PBMCs and plasma of patients with BD. Results: In a pilot study, we showed that BIRC5 gene expression increased in BD patients compared with healthy controls (P<0.05). Western blotting analysis indicated that there was an increase in phosphorylated survivin expression in PBMCs of BD patients. Our data from western blot analysis showed survivin level in plasma samples of BD patients was similar to healthy controls. No significant differences were observed between plasma survivin levels in the BD patients compared with control group (P>0.05). The expression of phosphorylated survivin at Thr34 in PBMCs of BD patients with active disease was increased. Plasma phosphorylated survivin levels in having BD patients were also downregulated compared to healthy individuals. Conclusion: Analysis of PBMCs indicated increasing expression level of phosphorylated survivin in PBMCs of BD patients. There was also a downregulation in phosphorylated survivin levels in plasma of BD patients.

An inhibitor of apoptosis protein (EsIAP1) from Chinese mitten crab Eriocheir sinensis regulates apoptosis through inhibiting the activity of EsCaspase-3/7-1

Inhibitor of apoptosis proteins (IAPs) maintain the balance between cell proliferation and cell death by inhibiting caspase activities and mediating immune responses. In the present study, a homolog of IAP (designated as EsIAP1) was identified from Chinese mitten crab Eriocheir sinensis. EsIAP1 consisted of 451 amino acids containing two baculoviral IAP repeat (BIR) domains with the conserved Cx2 Cx6 Wx3 Dx5 Hx6 C motifs. EsIAP1 mRNA was expressed in various tissues and its expression level in hemocytes increased significantly (p < 0.01) at 12–48 h after lipopolysaccharide stimulation. In the hemocytes, EsIAP1 protein was mainly distributed in the cytoplasm. The hydrolytic activity of recombinant EsCaspase-3/7-1 against the substrate Ac-DEVD-pNA decreased after incubation with rEsIAP1. Moreover, rEsIAP1 could directly combine with rEsCaspase-3/7-1 in vitro. After EsIAP1 was interfered by dsRNA, the mRNA expression and the hydrolytic activity of EsCaspase-3/7-1 increased significantly, which was 2.26-fold (p < 0.05) and 1.71-fold (p < 0.05) compared to that in the dsGFP group, respectively. These results collectively demonstrated that EsIAP1 might play an important role in apoptosis pathway by regulating the activity of EsCaspase-3/7-1 in E. sinensis.

Polymorphisms in Survivin (BIRC5 Gene) Are Associated with Age of Onset in Breast Cancer Patients

Survivin, encoded by BIRC5 gene (baculoviral IAP repeat containing 5), belongs to the family of inhibitors of apoptosis proteins (IAPs). In mammalian cells it participates in the control of mitosis, apoptosis regulation, and cellular stress response. Its expression is increased in almost all types of cancers. The aim of this study was to investigate the role of BIRC5 polymorphisms in breast cancer (BC) and to connect survivin expression with various clinicopathological characteristics of BC patients. Blood and archival tumour tissue samples were collected from 26 BC patients from Croatia. Survivin expression was determined immunohistochemically. BIRC5 promoter, coding region, and 3'UTR were genotyped. DNA from 74 healthy women was used as control. BIRC5 polymorphisms and survivin expression were tested against age of onset, histological grade, tumour type and size, lymph node status, oestrogen, progesterone, Her2, and Ki67 status. Numbers of samples with weak, moderate, and strong survivin expression were 9 (33.3%), 11 (40.7%), and 7 (25.9%), respectively. Most patients had nuclear survivin staining (92.6%). High survivin expression was significantly associated with negative oestrogen receptor status (p=0.007) and positive Ki67 expression (p=0.032). Ki67 expression was also positively correlated with histological grade (p=0.0009). Fourteen polymorphisms were found in BC samples, located mostly in promoter and 3'UTR of BIRC5. There was no significant difference in the distribution of polymorphisms between BC and control samples. Among clinicopathological characteristics of BC patients, alleles of five BIRC5 polymorphisms were associated with younger age of onset: c.-644T>C (55.8 years [y] vs. 48.1 y; p=0.006), c.-241C>T (54.2 y vs. 45.0; p=0.029), c.9809T>C (55.8 y vs. 48.1 y; p=0.006), c.-1547C>T (58.3 y vs. 50.9 y; p=0.011), and c.9386T>C (50.8 y vs. 59.5 y; p=0.004). To assess the significance of BIRC5 polymorphisms and survivin expression as predictive and prognostic biomarkers for BC further research with a larger sample size is needed.

The inhibitor of apoptosis protein MoBir1 is involved in the suppression of hydrogen peroxide-induced fungal cell death, reactive oxygen species generation, and pathogenicity of rice blast fungus

The inhibitor of apoptosis protein (IAP) family has been identified in a variety of organisms. All IAPs contain one to three baculoviral IAP repeat (BIR) domains, which are required for anti-apoptotic activity. Here, we identified a type II BIR domain-containing protein, MoBir1, in the rice blast fungus Magnaporthe oryzae. Expression of the MoBIR1 gene in Saccharomyces cerevisiae suppressed hydrogen peroxide-induced cell death and delayed yeast cell chronological aging. Delayed aging was found to require the carboxyl terminus of MoBir1. M. oryzae transformants overexpressing the MoBIR1 gene demonstrated increased growth rate and biomass, delayed mycelial aging, and enhanced resistance to hydrogen peroxide but reduced reactive oxygen species generation and virulence. Moreover, MoBIR1-overexpressing transformants exhibited anti-apoptotic activity. However, MoBIR1 silencing resulted in no obvious phenotypic changes, compared with the wild-type M. oryzae strain Guy11. Our findings broaden the knowledge on fungal type II BIR domain-containing proteins.

Characterization of an inhibitor of apoptosis gene (BmSurvivin-2) from the silkworm, Bombyx mori

The inhibitor of apoptosis proteins (IAP) plays an important role in maintaining the balance between cell proliferation and cell death. Here, we describe an IAP named BmSurvivin-2 isolated from tissues of Bombyx mori that contains only one baculoviral IAP repeat (BIR) domain and lacks a really interesting new gene (RING) finger domain. Cell viability and DNA fragment analysis showed that over-expression of BmSurvivin-2 could inhibit actinomycin D (ActD)-induced apoptosis in Sf9 cells, and its anti-apoptotic activity was dependent on its N-terminal BIR domain. Real-time PCR analyses indicated that BmSurvivin-2 mRNA was expressed in all tissues of silkworm and the highest expression level was found in testis and head. Expression of BmSurvivin-2 was found to gradually increase during the wandering stage of silkworm and decreased after wandering. Similar to deterin but not survivin, BmSurvivin-2 was primarily located in the cytoplasm. All these results provide insight into the role of a novel IAP in the silkworm, B. mori.