Inhibitor Of Survivin Research Articles

α5‐nAChR and survivin: Two potential biological targets in lung adenocarcinoma

Recent studies have shown that the overexpression of α5 nicotinic acetylcholine receptor (α5-nAChR) is associated with nicotine-related lung carcinogenesis. Survivin is one of the biomarkers of a worse prognosis for smoking-related lung cancer. The aim of this study is to investigate the association of α5-nAChR, survivin, and clinical outcomes in lung adenocarcinoma (LUAD). We analyzed the expression level and correlation of CHRNA5 (encoding α5-nAChR) and BIRC5 (encoding survivin) in LUAD with The Cancer Genome Atlas data set. The relationship between overall survival (OS) and the expression of CHRNA5 or/and BIRC5 was evaluated by the Kaplan-Meier method and Cox proportional hazards model. Moreover, our results showed that the expression of α5-nAChR mediated survivin expression in lung cancer cells and in lung tumor xenografts. Relationships between the expression of α5-nAChR and/or survivin with clinical-pathological characteristics were analyzed using LUAD tissue samples. The results showed that expression of α5-nAChR was correlated with survivin expression in vitro and in vivo. The group coexpressing α5-nAChR and survivin had a worse prognosis than other subgroups in LUAD (p < .05). In conclusion, ascertaining the expression of both α5-nAChR and survivin provides a better measure of prognosis for LUAD patients. The combined inhibition of α5-nAChR and survivin may be a promising multitargeted gene therapeutic strategy in LUAD diagnosis.

Inhibition of survivin induces spindle disorganization, chromosome misalignment, and DNA damage during mouse embryo development

ABSTRACT The early embryonic development is important for the subsequent embryo implantation, and any defects in this process can lead to embryonic aneuploidy, which causes miscarriage and birth defects. Survivin is the member of inhibitor of apoptosis protein (IAP) family, and it is also an essential subunit of chromosomal passenger complex (CPC), which regulates both apoptosis and cell cycle control in many models. However, the roles of survivin in mouse early embryos remain unclear. In the present study, we showed that survivin activity was essential for mouse early embryo development. Our results showed that survivin mainly accumulated at chromosomes at metaphase stage and located at the spindle midzone at anaphase and telophase stages during the first cleavage. Loss of survivin activity led to the failure of cleavage in early mouse embryos. Further analysis indicated that survivin involved into spindle organization and chromosome alignment. Moreover, inhibition of survivin induced oxidative stress and DNA damage, showing with the increase of ROS level, the positive γH2A signal, and the increase of Rad51 level. We also observed the occurrence of autophagy and apoptosis in the survivin-inhibited embryos. In summary, our study suggested that survivin was a critical regulator for early embryo development through its regulation on spindle organization, chromosome alignment, and DNA damage.

LKB1 inactivation leads to centromere defects and genome instability via p53-dependent upregulation of survivin.

Inactivating mutations in the liver kinase B1 (LKB1) tumor suppressor gene underlie Peutz-Jeghers syndrome (PJS) and occur frequently in various human cancers. We previously showed that LKB1 regulates centrosome duplication via PLK1. Here, we report that LKB1 further helps to maintain genomic stability through negative regulation of survivin, a member of the chromosomal passenger complex (CPC) that mediates CPC targeting to the centromere. We found that loss of LKB1 led to accumulation of misaligned and lagging chromosomes at metaphase and anaphase and increased the appearance of multi- and micro-nucleated cells. Ectopic LKB1 expression reduced these features and improved mitotic fidelity in LKB1-deficient cells. Through pharmacological and genetic manipulations, we showed that LKB1-mediated repression of survivin is independent of AMPK, but requires p53. Consistent with the key influence of LKB1 on survivin expression, immunohistochemical analysis indicated that survivin is highly expressed in intestinal polyps from a PJS patient. Lastly, we reaffirm a potential therapeutic avenue to treat LKB1-mutated tumors by demonstrating the increased sensitivity to survivin inhibitors of LKB1-deficient cells.

JNK inhibition alleviates oxidative DNA damage, germ cell apoptosis, and mitochondrial dysfunction in testicular ischemia reperfusion injury.

The aim of this study is to determine whether the c-Jun N-terminal kinase (JNK) signaling is a regulator of oxidative DNA damage, germ cell apoptosis (GCA), and mitochondrial dysfunction during testicular ischemia reperfusion injury (tIRI) using the JNK inhibitor SP600125. Male Sprague Dawley rats (n = 36) were equally divided into three groups: sham, tIRI only, and tIRI + SP600125 (15mg/kg). Testicular ischemia was induced for 1h followed by 4h of reperfusion prior to animal sacrifice. Spermatogenesis was evaluated by light microscopy, while expression of oxidative stress and GCA-related mRNAs and proteins were evaluated by real-time polymerase chain reaction and colorimetric assays, respectively. Expressions of JNK, p53, and survivin were detected by immunofluorescence (IF) staining. Indicators of mitochondrial dysfunction were examined by western blot analysis and colorimetric assay. In comparison to sham, the tIRI testes showed a significant increase in lipid and protein oxidation products. Oxidative DNA damage was reflected by a significant increase in the number of DNA strand breaks, increased concentration of 8-OHdG, and elevated poly (ADP-ribose) polymerase activity. Spermatogenic damage was associated with the activation of caspase 3 and elevated Bax to Bcl2 ratio. This was also accompanied by a significantly heightened IF expression of the phosphorylated forms of JNK and p53 paralled with the suppression of survivin. Mitochondrial dysfunction was reflected by NAD+ depletion, overexpression of uncoupling protein 2, and increased level of cytochrome c. Such tIRI-induced modulations were all attenuated by SP600125 treatment prior to reperfusion. In conclusion, JNK signaling regulates oxidative DNA damage, GCA, and mitochondrial dysfunction through activation of p53 and suppression of survivin during tIRI.

The Sensitization of Melatonin in Osteosarcoma Cells by Suppression of Anti-Apoptotic Proteins

Background:Investigation of anti-cancer agents with desirable selective toxicity is critical for cancer therapy. The use of natural adjuvants can be a promising option in reducing the toxicity of the anti-cancer agent. The aim of this study was to investigate the potential application of melatonin (MLT) as a natural adjuvant molecule along with doxorubicin (DOX) to induce cytotoxicity in osteosarcoma (OS) cells.Methods:Human OS cell lines included Saos-2, MG-63, and Human Bone Marrow Mesenchymal Stem Cells (hBM-MSCs) were treated with free DOX, free MLT, DOX-loaded NPs (DOX-NPs), MLT-loaded NPs (MLT-NPs), combination of DOX and MLT (DOX-MLT) and combination of DOX and MLT-loaded NPs (DOX-MLT-NPs) in separated cell culture. Cell proliferation of experiments were evaluated by MTT assay after 24 h. Total protein levels were determined by enzyme immunoassay ELISA.Results:Herein, we found the combination of MLT with DOX, especially formulated in nano-form, is resulted in a significant reduction in the protein levels of both X-linked Inhibitor of Apoptosis (XIAP) and Survivin (p&lt;0.0001). Indeed, there was a significant decrease in the expression of XIAP and Survivin when MLT is combined with DOX compared to the individual treatments.Conclusion:Our findings indicated the synergism of the antitumor effect could be due to the down-regulation of XIAP and Survivin in the levels of protein.

Ursolic acid potentiated oxaliplatin to induce apoptosis in colorectal cancer RKO cells.

Ursolic acid (UA) is found in multiple anticancer herbs and has shown anticancer effects in colorectal cancer (CRC) cells. The present study aimed to observe the effects of a combination of UA and oxaliplatin (Oxa), a frequently used chemotherapeutic drug in CRC, on human CRC RKO cells. The results showed that UA and Oxa synergistically inhibited the proliferation of RKO cells. A combination of UA and Oxa induced apoptosis in RKO cells and increased the activities of caspase-3, caspase-8, and caspase-9. Z-VAD-FMK, a caspase inhibitor, significantly antagonized UA- and Oxa-activated caspase-3, caspase-8, and caspase-9 and induced apoptosis. In addition, UA and Oxa downregulated the expression of X-linked inhibitor of apoptosis (XIAP) and Survivin in RKO cells. These observations suggested that a combination of UA and Oxa elicited synergistically anticancer effects in RKO cells and provided new evidence for potential application of UA and Oxa for CRC treatment.

Role of mutant KRAS as a biomarker in FL118-induced apoptosis, reactive oxygen species (ROS) production and inhibition of survivin, Mcl-1 and XIAP in human bladder cancer.

e15651 Background: Effective treatment of bladder cancer patients has not been realized over the past two decades due to heterogeneity with key oncogenic and tumor suppressor gene mutations, which is a major hurdle for effective treatment of the disease. Methods: Cancer cell growth/viability was determined using MTT assays; protein gene expression profiles were determined by both Western blots and proteomics technologies; PARP cleavage were determined by Western blots; genetic modulation of protein gene expression was realized by shRNA silencing or forced expression of the gene; reactive oxygen species (ROS) production was measured using a ROS assay kit; and human bladder xenograft tumor growth was determined using animal models. Results: Our study indicated that FL118, an innovative small molecule, exhibits differential anticancer efficacy in high-grade bladder cancer cell lines (HT1376, T24, UMUC-3). FL118 is highly effective at inhibiting the viability of T24 and UMUC-3 bladder cancer cells, which have Hras and Kras mutations, respectively. In contrast, HT1376 with wild-type Ras exhibits insensitivity to FL118-mediated inhibition of cell viability. Consistently, FL118 strongly induced PARP cleavage (hallmark of apoptosis) and inhibited the expression of survivin, XIAP and/or Mcl-1 in both T24 and UMUC-3 cells but not in the HT1376 cells. Our studies further indicated that the constitutive AKT and ERK1/2 signaling does not play a major role in these FL118-mediated effects. Instead, mutant Kras appeared to be involved in FL118 efficacy and played a positive role in mediating FL118 effects. Silencing of mutant Kras via shRNA reduced both FL118-induced PARP cleavage and downregulation of survivin, XIAP and Mcl-1 in UMUC-3 cells, suggesting mutant Kras is required for FL118 to exhibit high efficacy. FL118 increases ROS production in T24 and UMUC-3 cells but not in HT1376 cells. Silencing of mutant Kras with shRNA in UMUC-3 cells significantly reduced FL118-mediated ROS generation. Additionally, proteomics analyses of UMUC3 and HT1376 cell protein profiles after FL118 treatment support the obtained results described above. Consistent with these in vitro results, in vivo studies indicated that UMUC3 is highly sensitive and HT1376 is highly resistant to FL118 treatment. Conclusions: Our studies suggest that mutant Kras is a favorable biomarker for FL118 targeted treatment in human bladder cancer.

Synthesis and Identification of a Novel Lead Targeting Survivin Dimerization for Proteasome-Dependent Degradation

Survivin, a homodimeric member of the Inhibitor of Apoptosis Protein (IAP) family, is required for cancer cell survival and overexpressed in almost all solid tumors. However, targeting survivin has been challenging due to its "undruggable" nature. Recently, we used a novel approach to target the dimerization interface and identified inhibitors of two scaffolds that can directly bind to and inhibit survivin dimerization. One of the scaffolds, represented by the compound LQZ-7, contains an undesirable labile hydrazone linker and a potentially nonfunctional furazanopyrazine ring that we attempted to eliminate in this study. We found one compound, 7I, that is more active than the parent compound, LQZ-7, and when given orally effectively inhibits xenograft tumor growth and induces survivin loss in tumors. These findings indicate that 7I with a stable linker and a quinoxaline ring can be used as a lead for further optimization of this novel class of survivin inhibitors.

Arsenic trioxide-induced p38 MAPK and Akt mediated MCL1 downregulation causes apoptosis of BCR-ABL1-positive leukemia cells

In this study, we investigated the mechanisms underlying arsenic trioxide (ATO)-induced death of human BCR-ABL1-positive K562 and MEG-01 cells. ATO-induced apoptotic death in K562 cells was characterized by ROS-mediated mitochondrial depolarization, MCL1 downregulation, p38 MAPK activation, and Akt inactivation. ATO-induced BCR-ABL1 downregulation caused Akt inactivation but not p38 MAPK activation. Akt inactivation increased GSK3β-mediated MCL1 degradation, while p38 MAPK-mediated NFκB activation coordinated with HDAC1 suppressed MCL1 transcription. Inhibition of p38 MAPK activation or overexpression of constitutively active Akt increased MCL1 expression and promoted the survival of ATO-treated cells. Overexpression of MCL1 alleviated mitochondrial depolarization and cell death induced by ATO. The same pathway was found to be involved in ATO-induced death in MEG-01 cells. Remarkably, YM155 synergistically enhanced the cytotoxicity of ATO on K562 and MEG-01 cells through suppression of MCL1 and survivin. Collectively, our data indicate that ATO-induced p38 MAPK- and Akt-mediated MCL1 downregulation triggers apoptosis in K562 and MEG-01 cells, and that p38 MAPK activation is independent of ATO-induced BCR-ABL1 suppression.

MP51-16 DECREASING SURVIVIN BY YM155 REVERSES CABAZITAXEL RESISTANCE IN PROSTATE CANCER

You have accessJournal of UrologyProstate Cancer: Basic Research & Pathophysiology II (MP51)1 Apr 2020MP51-16 DECREASING SURVIVIN BY YM155 REVERSES CABAZITAXEL RESISTANCE IN PROSTATE CANCER Takeshi Miyao*, Hidekazu Koike, Akira Otsu, Daisuke Oka, Masanori Aoki, Hiroshi Nakayama, Yoshiyuki Miyazawa, Seiji Arai, Yoshitaka Sekine, Hiroshi Matsui, Yasuhiro Shibata, and Kazuhiro Suzuki Takeshi Miyao*Takeshi Miyao* More articles by this author , Hidekazu KoikeHidekazu Koike More articles by this author , Akira OtsuAkira Otsu More articles by this author , Daisuke OkaDaisuke Oka More articles by this author , Masanori AokiMasanori Aoki More articles by this author , Hiroshi NakayamaHiroshi Nakayama More articles by this author , Yoshiyuki MiyazawaYoshiyuki Miyazawa More articles by this author , Seiji AraiSeiji Arai More articles by this author , Yoshitaka SekineYoshitaka Sekine More articles by this author , Hiroshi MatsuiHiroshi Matsui More articles by this author , Yasuhiro ShibataYasuhiro Shibata More articles by this author , and Kazuhiro SuzukiKazuhiro Suzuki More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000913.016AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Cabazitaxel has exhibited promising anticancer activity for the treatment of prostate cancer. However, many patients acquire resistance to therapeutic agents leading to treatment failure. The objective of this study was to determine whether treatment with YM155, a novel small molecule inhibitor of survivin, could reverse Cabazitaxel resistance in a Cabazitaxel-resistant prostate cancer. METHODS: We induced a Cabazitaxel-resistant prostate cancer cell line (22Rv1-CR). We showed that survivin gene expression was significantly up-regulated in 22Rv1-CR compared with that in its parent cells (22Rv1). Therefore, we hypothesized that targeting of survivin in 22Rv1-CR could reverse the resistant phenotype in tumor cells, thereby enhancing the therapeutic efficacy of Cabazitaxel. We used both in vitro and in vivo models to test the efficacy of YM155 either as a single agent or in combination with Cabazitaxel. RESULTS: In 22Rv1-CR cells, YM155 significantly decreased survivin gene expression levels and cell proliferation in a dose-dependent manner in vitro. In addition, YM155 treatment significantly reversed Cabazitaxel resistance in 22Rv1-CR cells. In a nude mouse tumor xenograft model, YM155 significantly enhanced the antitumor effects of Cabazitaxel in 22Rv1-CR tumor. CONCLUSIONS: Our results suggest a potentially novel strategy to use YM155 to overcome the resistance in tumor cells, thereby enhancing the effectiveness of Cabazitaxel-therapy in prostate cancer. Source of Funding: none © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e770-e770 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Takeshi Miyao* More articles by this author Hidekazu Koike More articles by this author Akira Otsu More articles by this author Daisuke Oka More articles by this author Masanori Aoki More articles by this author Hiroshi Nakayama More articles by this author Yoshiyuki Miyazawa More articles by this author Seiji Arai More articles by this author Yoshitaka Sekine More articles by this author Hiroshi Matsui More articles by this author Yasuhiro Shibata More articles by this author Kazuhiro Suzuki More articles by this author Expand All Advertisement PDF downloadLoading ...

Phase-I trial of survivin inhibition with EZN-3042 in dogs with spontaneous lymphoma

BackgroundLymphoma is a common cancer in dogs. While most dogs receiving chemotherapy experience remission, very few are cured, and median survival times are generally in the 12-month range. Novel approaches to treatment are unquestionably needed. The Inhibitor of Apoptosis Protein (IAP) family member survivin, which is one of the most commonly overexpressed proteins in human cancer, plays a key role in apoptosis resistance, a major cause of drug-resistant treatment failure. Survivin targeting therapies have shown promise preclinically; however, none have been evaluated in dogs to date. The goal of the current study was to determine the safety and pharmacodynamic effects of systemic administration of the anti-survivin locked nucleic acid antisense oligonucleotide EZN-3042 in dogs with lymphoma.ResultsWe performed a prospective phase-I clinical trial in dogs with biopsy-accessible peripheral nodal lymphoma. Eighteen dogs were treated with EZN-3042 as a 2-h IV infusion at 5 dose levels, from 3.25 to 8.25 mg/kg twice weekly for 3 treatments. No dose-limiting toxicities were encountered. Reduction in tumor survivin mRNA and protein were observed in 3 of 5 evaluable dogs at the 8.25 mg/kg dose cohort.ConclusionsIn conclusion, reduced survivin expression was demonstrated in lymphoma tissues in the majority of dogs treated with EZN-3042 at 8.25 mg/kg twice weekly, which was associated with minimal adverse effects. This dose may be used in future studies of EZN-3042/chemotherapy combinations in dogs with spontaneous lymphoma and other cancers.

Aurora B kinase as a therapeutic target in acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is curable with standardized chemotherapy. However, the development of novel therapies is still required, especially for patients with relapsed or refractory disease. By utilizing an in vitro drug screening system, active molecular targeting agents against ALL were explored in this study. By the in vitro drug sensitivity test, 81 agents with various actions were screened for their cytotoxicity in a panel of 22 ALL cell lines and ALL clinical samples. The drug effect score (DES) was calculated from the dose-response of each drug for comparison among drugs or samples. Normal peripheral blood mononuclear cells were also applied onto the drug screening to provide the reference control values. The drug combination effect was screened based on the Bliss independent model, and validated by the improved isobologram method. On sensitivity screening in a cell line panel, barasertib-HQPA which is an active metabolite of barasertib, an aurora B kinase inhibitor, alisertib, an aurora A kinase inhibitor, and YM155, a survivin inhibitor, were effective against the broadest range of ALL cells. The DES of barasertib-HQPA was significantly higher in ALL clinical samples compared to the reference value. There were significant correlations in DES between barasertib-HQPA and vincristine or docetaxel. In the drug combination assay, barasertib-HQPA and eribulin showed additive to synergistic effects. Aurora B kinase was identified to be an active therapeutic target in a broad range of ALL cells. Combination therapy of barasertib and a microtubule-targeting drug is of clinical interest.

Long Non-coding RNA CCAT1 Sponges miR-454 to Promote Chemoresistance of Ovarian Cancer Cells to Cisplatin by Regulation of Surviving.

PurposeColon cancer-associated transcript 1 (CCAT1) was identified as an oncogenic long non-coding RNA (lncRNA) in a variety of cancers. However, there was a lack of understanding of the mechanism by which CCAT1 conferred cisplatin (also known as DDP) resistance in ovarian cancer cells.Materials and MethodsCell viability of A2780, SKOV3, A2780/DDP, and SKOV3/DDP cells upon cisplatin treatment was monitored by MTT assay. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) detected the expression levels of CCAT1 and miR-454. The effect of sh-CCAT1 on cisplatin response was investigated in xenografts study. Bioinformatic analysis, luciferase reporter assay and qRT-PCR were conducted to validate the direct interaction among CCAT1, miR-454, and survivin. Apoptosis was determined by flow cytometry after dual staining of Annexin-V-FITC/propidium iodide, and the expression of apoptosis-related proteins Bcl-2, Bax and survivin were detected by qRT-PCR and Western blotting. Xenograft study was conducted to monitor in vivo tumor formation.ResultsCCAT1 was highly expressed in cisplatin-resistant ovarian cancer cell line A2780/DDP and SKOV3/DDP. Knockdown of CCAT1 restored sensitivity to cisplatin in vitro and in vivo. Our data revealed that silencing of CCAT1 promoted cisplatin-induced apoptosis via modulating the expression of pro- or anti-apoptotic proteins Bax, Bcl-2, and survivin. CCAT1 directly interacted with miR-454, and miR-454 overexpression potentiated cisplatin-induced apoptosis. Survivin was identified as a functional target of miR-454, restoration of survivin attenuated the effect of miR-454 on cisplatin response. In addition, miR-454 inhibitor or overexpression of survivin was found to abolish sh-CCAT1–induced apoptosis upon cisplatin treatment.ConclusionCCAT1/miR-454/survivin axis conferred cisplatin resistance in ovarian cancer cells.

Testing of the Survivin Suppressant YM155 in a Large Panel of Drug-Resistant Neuroblastoma Cell Lines.

The survivin suppressant YM155 is a drug candidate for neuroblastoma. Here, we tested YM155 in 101 neuroblastoma cell lines (19 parental cell lines, 82 drug-adapted sublines). Seventy seven (77) cell lines displayed YM155 IC50s in the range of clinical YM155 concentrations. ABCB1 was an important determinant of YM155 resistance. The activity of the ABCB1 inhibitor zosuquidar ranged from being similar to that of the structurally different ABCB1 inhibitor verapamil to being 65-fold higher. ABCB1 sequence variations may be responsible for this, suggesting that the design of variant-specific ABCB1 inhibitors may be possible. Further, we showed that ABCC1 confers YM155 resistance. Previously, p53 depletion had resulted in decreased YM155 sensitivity. However, TP53-mutant cells were not generally less sensitive to YM155 than TP53 wild-type cells in this study. Finally, YM155 cross-resistance profiles differed between cells adapted to drugs as similar as cisplatin and carboplatin. In conclusion, the large cell line panel was necessary to reveal an unanticipated complexity of the YM155 response in neuroblastoma cell lines with acquired drug resistance. Novel findings include that ABCC1 mediates YM155 resistance and that YM155 cross-resistance profiles differ between cell lines adapted to drugs as similar as cisplatin and carboplatin.

Investigating the role of the innate immune response in relapse or blast crisis in chronic myeloid leukemia

Chronic myeloid leukemia (CML) is characterized by expression of the tyrosine kinase oncogene, Bcr–abl. Tyrosine kinase inhibitors (TKI) induce prolonged remission in CML, and therapy discontinuation is an accepted approach to patients with reduction in Bcr–abl transcripts of four logs or greater. Half such individuals sustain a therapy free remission, but molecular mechanisms predicting relapse are undefined. We found relative calpain inhibition in CML cells with stabilization of calpain substrates, including βcatenin and Xiap1. Since the Survivin gene is activated by βcatenin, this identified two apoptosis-resistance mechanisms. We found that Survivin impaired apoptosis in leukemia stem cells (LSCs) and Xiap1 in CML granulocytes. Consistent with this, we determined treatment with an inhibitor of Survivin, but not Xiap1, prevented relapse during TKI treatment and after therapy discontinuation in a murine CML model. By transcriptome profiling, we identified activation of innate immune response pathways in murine CML bone marrow progenitors. This was increased by TKI treatment alone, but normalized with addition of a Survivin inhibitor. We found that activation of the innate immune response induced rapid blast crisis in untreated CML mice, and chronic phase relapse during a TKI discontinuation attempt. These results suggest that extrinsic stress exerts adverse effects on CML-LSCs.

Discovery of inner centromere protein-derived small peptides for cancer imaging and treatment targeting survivin.

Survivin belongs to the inhibitor of apoptosis protein family, which is consistently overexpressed in most cancer cells but rarely expressed in normal adult tissues. Therefore, the detection and inhibition of survivin are regarded as attractive strategies for cancer‐specific treatment. In this study, we designed and synthesized 7‐19 residues of inner centromere protein (INCENP)‐derived small peptides (INC peptides) as novel survivin‐targeting agents. The INC peptides showed binding affinity for the human survivin protein (K d = 91.4‐255 nmol L−1); INC16‐22, which contains residues 16‐22 of INCENP, showed the highest affinity (91.4 nmol L−1). Confocal fluorescence imaging showed consistent colocalization of FITC‐INC16‐22 and survivin in cell lines. Nona‐arginine‐linked INC16‐22 (r9‐INC16‐22) rendered INC16‐22 cells penetrable and strongly inhibited cell growth of MIA PaCa‐2 cells (52% inhibition at 1.0 µmol L−1) and MDA‐MB‐231 cells (60% inhibition at 10 µmol L−1) as determined by MTT assays. The exposure of MIA PaCa‐2 cells to 40 µmol L−1 r9‐INC16‐22 apparently reduced the intracellular protein expression levels of survivin. However, cleaved caspase‐3 was significantly increased in cells treated with r9‐INC16‐22, even at 10 µmol L−1, compared to untreated cells. Flow cytometry revealed that r9‐INC16‐22 strongly induced apoptosis in MIA PaCa‐2 cells. These results indicate that the cytotoxic effects of r9‐INC16‐22 could be mediated mainly through the disruption of survivin‐dependent antiapoptotic functions and partly because of the direct degradation of the survivin protein. Our findings suggest that INC peptides can act as useful scaffolds for novel cancer imaging and anticancer agents.

Chromomycin A3 suppresses cholangiocarcinoma growth by induction of S phase cell cycle arrest and suppression of Sp1‑related anti‑apoptotic proteins.

Cholangiocarcinoma (CCA) is a cancer of biliary epithelium. Late diagnosis and resistance to conventional chemotherapy are the major obstacles in CCA treatment. Increased expression of anti-apoptotic proteins are observed in CCA, which might confer chemoresistance. Thus, modulations of anti-apoptotic proteins leading to apoptotic induction is the focus of this study. Chromomycin A3 (CMA3), an anthraquinone glycoside-mithramycin A analog, was selected. CMA3 strongly binds to GC-rich regions in DNA, where specificity protein 1 (Sp1), a common transcription factor of apoptosis-related proteins, is preferentially bounded. The effects of CMA3 on anti-proliferation, cell cycle arrest and apoptosis induction in CCA cells were demonstrated by MTT assay, flow cytometry and western blot analysis. The results showed CMA3 suppressed cell proliferation in vitro in the nM range. At low doses, CMA3 inhibited cell cycle progression at S phase, while it promoted caspase-dependent apoptosis at higher doses. CMA3 induced effects of apoptosis were through the suppression of Sp1-related anti-apoptotic proteins, FADD-like IL-1β-converting enzyme-inhibitory protein, myeloid cell leukemia-1, X-linked inhibitor of apoptosis protein, cellular inhibitor of apoptosis and survivin. The anti-CCA effects of CMA3 were confirmed in the xenograft mouse model. CMA3 retarded xenograft tumor growth. Taken together, CMA3 induced apoptosis in CCA cells by diminishing the Sp1-related anti-apoptotic proteins is demonstrated. CMA3 might be useful as a chemosensitizing agent.

The role of survivin in the progression of pancreatic ductal adenocarcinoma (PDAC) and a novel survivin-targeted therapeutic for PDAC.

Treating pancreatic ductal adenocarcinoma (PDAC) remains a major hurdle in the field of oncology. Less than half of patients respond to frontline chemotherapy and the pancreatic tumor microenvironment limits the efficacy of immunotherapeutic approaches. Targeted therapies could serve as effective treatments to enhance the clinical response rate. One potential therapeutic target is survivin, a protein that is normally expressed during embryonic and fetal development and has a critical impact on cell cycle control and apoptosis. In adulthood, survivin is not present in most normal adult cells, but is significantly re-expressed in tumor tissues. In PDAC, elevated survivin expression is correlated with treatment resistance and lower patient survival, although the underlying mechanisms of survivin's action in this type of cancer is poorly understood. Using patient derived xenografts of PDAC and their corresponding primary pancreatic cancer lines (PPCL-46 and PPCL-LM1) possessing increased expression of survivin, we aimed to evaluate the therapeutic response of a novel survivin inhibitor, UFSHR, with respect to survivin expression and the tumorigenic characteristics of PDAC. Cell viability and apoptosis analyses revealed that repressing survivin expression by UFSHR or YM155, a well-known inhibitor of survivin, in PPCLs effectively reduces cell proliferation by inducing apoptosis. Tumor cell migration was also hindered following treatment with YM155 and UFSHR. In addition, both survivin inhibitors, particularly UFSHR, effectively reduced progression of PPCL-46 and PPCL-LM1 tumors, when compared to the untreated cohort. Overall, this study provides solid evidence to support the critical role of survivin in PDAC progression and proposes a novel survivin inhibitor UFSHR that can become an alternative strategy for this type of cancer.

Restoring apoptosis dysregulation using survivin inhibitor in nasopharyngeal cancer.

Restoring apoptosis dysregulation via survivin inhibition has been investigated in several cancers. In Epstein-Barr Virus (EBV)-driven nasopharyngeal cancer (NPC), virally induced oncogenes can upregulate survivin. Therefore, we seek to investigate the therapeutic efficacy of YM-155 (a survivin inhibitor) in NPC, both in vitro and in vivo models. Cytotoxicity, apoptosis, and active-caspase 3 expression assays were performed. Both NPC tissue and cells expressed high levels of survivin which were inhibited by YM-155 in a dose-dependent manner. In addition, YM-155 induced apoptosis of NPC cells with an IC50 of 100 nM and inhibited tumor growth in vivo (P < 0.05). YM-155 in combination with cisplatin or radiation significantly increased overall cytotoxicity as compared to YM-155 monotherapy. In the xenograft model, YM-155 plus radiation additively achieved significantly higher percentage of active-caspase 3-positive tumor cells than radiation alone (P < 0.05). YM-155 is a potential therapeutic agent for NPC through inhibiting survivin and restoring apoptosis dysregulation.

Typhonium flagelliforme extract induce apoptosis in breast cancer stem cells by suppressing survivin.

Breast cancer stem cells (bCSCs) are a small population of cancer-initiating cells within breast cancer, characterized as CD44+ CD24-/low. bCSCs develop apoptosis resistance by expressing survivin and suppressing caspase-9 and caspase-3 expression. Typhonium flagelliforme tuber extract (TFTe) can induce apoptosis in several types of cancer cells; however, the effects of TFTe to induce the bCSCs remain unclear. This study aimed to investigate the effects of TFTe on apoptosis induction in bCSCs through the suppression of survivin and the exhibition of caspase-9 and caspase-3. This study employed a posttest only, control group design. To analyze the apoptotic index, TFTe, at concentrations of 25 (Tf1d), 50.89 (Tf2d), and 100 μg/mL (Tf3d) were used to treat bCSCs for 24 h, in a humidified incubator containing 5% CO2, at 37°C. The control group was exposed to dimethyl sulfoxide. Apoptosis was measured by propidium iodide and acridine orange double-staining, and the expression levels of survivin, caspase-9, and caspase-3 were assessed by immunocytochemistry. Differences were analyzed by the independent Student's t-test, to compare two groups, and the Kruskal-Wallis test, to compare more than two groups. P < 0.05 was considered statistically significant. TFTe inhibited bCSC proliferation, with an IC50 value of 50.89 μg/mL, and significantly induced apoptosis in bCSCs (P < 0.001). TFTe also significantly decreased the expression levels of survivin in bCSCs (P < 0.001) and increased the expression levels of caspase-9 and caspase-3 (P < 0.001). TFTe can induce apoptosis in bCSCs by decreasing survivin expression levels and increasing the levels of caspase-9 and caspase-3.