B5, a thioredoxin reductase inhibitor, induces apoptosis in human cervical cancer cells by suppressing the thioredoxin system, disrupting mitochondrion-dependent pathways and triggering autophagy

The synthetic curcumin analog B5 is a potent inhibitor of thioredoxin reductase (TrxR) that has potential anticancer effects. The molecular mechanism underlying B5 as an anticancer agent is not yet fully understood. In this study, we report that B5 induces apoptosis in two human cervical cancer cell lines, CaSki and SiHa, as evidenced by the downregulation of XIAP, activation of caspases and cleavage of PARP. The involvement of the mitochondrial pathway in B5-induced apoptosis was suggested by the dissipation of mitochondrial membrane potential and increased expression of pro-apoptotic Bcl-2 family proteins. In B5-treated cells, TrxR activity was markedly inhibited with concomitant accumulation of oxidized thioredoxin, increased formation of reactive oxygen species (ROS), and activation of ASK1 and its downstream regulatory target p38/JNK. B5-induced apoptosis was significantly inhibited in the presence of N-acetyl-l-cysteine. Microscopic examination of B5-treated cells revealed increased presence of cytoplasmic vacuoles. The ability of B5 to activate autophagy in cells was subsequently confirmed by cell staining with acridine orange, accumulation of LC3-II, and measurement of autophagic flux. Unlike B5-induced apoptosis, autophagy induced by B5 is not ROS-mediated but a role for the AKT and AMPK signaling pathways is implied. In SiHa cells but not CaSki cells, B5-induced apoptosis was promoted by autophagy. These data suggest that the anticarcinogenic effects of B5 is mediated by complex interplay between cellular mechanisms governing redox homeostasis, apoptosis and autophagy.

[1]  J. Kangasjärvi,et al.  Specificity in ROS signaling and transcript signatures. , 2014, Antioxidants & redox signaling.

[2]  R. Franco,et al.  Oxidative stress, redox signaling, and autophagy: cell death versus survival. , 2014, Antioxidants & redox signaling.

[3]  N. Chandel,et al.  ROS Function in Redox Signaling and Oxidative Stress , 2014, Current Biology.

[4]  P. Dent,et al.  The role of cell signalling in the crosstalk between autophagy and apoptosis. , 2014, Cellular signalling.

[5]  R. Hondal,et al.  A direct and continuous assay for the determination of thioredoxin reductase activity in cell lysates. , 2013, Analytical biochemistry.

[6]  A. Holmgren,et al.  Thioredoxin system in cell death progression. , 2012, Antioxidants & redox signaling.

[7]  D. Klionsky,et al.  Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition) , 2012, Autophagy.

[8]  Robert Clarke,et al.  Guidelines for the use and interpretation of assays for monitoring autophagy , 2012 .

[9]  S. Katiyar,et al.  Grape Proanthocyanidins Induce Apoptosis by Loss of Mitochondrial Membrane Potential of Human Non-Small Cell Lung Cancer Cells In Vitro and In Vivo , 2011, PloS one.

[10]  S. Wesselborg,et al.  Role of AMPK-mTOR-Ulk1/2 in the Regulation of Autophagy: Cross Talk, Shortcuts, and Feedbacks , 2011, Molecular and Cellular Biology.

[11]  H. Ichijo,et al.  Mitogen-activated protein kinases in mammalian oxidative stress responses. , 2011, Antioxidants & redox signaling.

[12]  Hu Wei,et al.  Inhibition of thioredoxin reductase by auranofin induces apoptosis in adriamycin-resistant human K562 chronic myeloid leukemia cells. , 2011, Die Pharmazie.

[13]  X. Diao,et al.  Induction of autophagy-dependent apoptosis by the survivin suppressant YM155 in prostate cancer cells. , 2011, Cancer letters.

[14]  D. Hardie AMPK and autophagy get connected , 2011, The EMBO journal.

[15]  D. Sabatini,et al.  Structure of the human mTOR complex I and its implications for rapamycin inhibition. , 2010, Molecular cell.

[16]  K. Tonissen,et al.  Thioredoxin and Cancer: A Role for Thioredoxin in all States of Tumor Oxygenation , 2010, Cancers.

[17]  Markus R. Wenk,et al.  Dual Role of 3-Methyladenine in Modulation of Autophagy via Different Temporal Patterns of Inhibition on Class I and III Phosphoinositide 3-Kinase* , 2010, The Journal of Biological Chemistry.

[18]  C. Hutnik,et al.  p38 mitogen-activated protein kinase protects human retinal pigment epithelial cells exposed to oxidative stress. , 2009, Canadian journal of ophthalmology. Journal canadien d'ophtalmologie.

[19]  Elias S. J. Arnér Focus on mammalian thioredoxin reductases--important selenoproteins with versatile functions. , 2009, Biochimica et biophysica acta.

[20]  J. Bao,et al.  Polygonatum cyrtonema lectin induces apoptosis and autophagy in human melanoma A375 cells through a mitochondria-mediated ROS-p38-p53 pathway. , 2009, Cancer letters.

[21]  S. Ferrini,et al.  The redox state of the lung cancer microenvironment depends on the levels of thioredoxin expressed by tumor cells and affects tumor progression and response to prooxidants , 2008, International journal of cancer.

[22]  A. Mukherjee,et al.  The thioredoxin system: a key target in tumour and endothelial cells. , 2008, The British journal of radiology.

[23]  Zhishu Huang,et al.  Inhibition of Thioredoxin Reductase by Curcumin Analogs , 2008, Bioscience, biotechnology, and biochemistry.

[24]  A. Holmgren,et al.  Inhibition of the Human Thioredoxin System , 2008, Journal of Biological Chemistry.

[25]  Y. Kondo,et al.  Roles of the Akt/mTOR/p70S6K and ERK1/2 Signaling Pathways in Curcumin-Induced Autophagy , 2007, Autophagy.

[26]  A. Holmgren,et al.  Targeting thioredoxin reductase is a basis for cancer therapy by arsenic trioxide , 2007, Proceedings of the National Academy of Sciences.

[27]  T. Mak,et al.  XIAP Activity Dictates Apaf-1 Dependency for Caspase 9 Activation , 2007, Molecular and Cellular Biology.

[28]  A. Gross,et al.  Mitochondrial carriers and pores: Key regulators of the mitochondrial apoptotic program? , 2007, Apoptosis.

[29]  Sten Orrenius,et al.  Mitochondrial oxidative stress: implications for cell death. , 2007, Annual review of pharmacology and toxicology.

[30]  K. Becker,et al.  On the potential of thioredoxin reductase inhibitors for cancer therapy. , 2006, Seminars in cancer biology.

[31]  P. Marks Thioredoxin in cancer--role of histone deacetylase inhibitors. , 2006, Seminars in cancer biology.

[32]  Richard T. Lee,et al.  Role of thioredoxin in cell growth through interactions with signaling molecules. , 2006, Antioxidants & redox signaling.

[33]  Jinsong Liu,et al.  Selective killing of oncogenically transformed cells through a ROS-mediated mechanism by beta-phenylethyl isothiocyanate. , 2006, Cancer cell.

[34]  A. Chan,et al.  Curcumin Analogues as Potent Aldose Reductase Inhibitors. , 2006 .

[35]  B. Zhivotovsky,et al.  Inhibition of Mammalian thioredoxin reductase by some flavonoids: implications for myricetin and quercetin anticancer activity. , 2006, Cancer research.

[36]  A. Chan,et al.  Curcumin Analogs as Potent Aldose Reductase Inhibitors , 2006, Archiv der Pharmazie.

[37]  Kikuya Kato,et al.  High Thioredoxin Expression Is Associated with Resistance to Docetaxel in Primary Breast Cancer , 2005, Clinical Cancer Research.

[38]  Woojin Jeong,et al.  2-Cys peroxiredoxin function in intracellular signal transduction: therapeutic implications , 2005, Trends in Molecular Medicine.

[39]  N. Maulik,et al.  Resveratrol enhances neovascularization in the infarcted rat myocardium through the induction of thioredoxin-1, heme oxygenase-1 and vascular endothelial growth factor. , 2005, Journal of molecular and cellular cardiology.

[40]  A. Holmgren,et al.  Thioredoxin Reductase Is Irreversibly Modified by Curcumin , 2005, Journal of Biological Chemistry.

[41]  S. Rhee,et al.  Peroxiredoxins: a historical overview and speculative preview of novel mechanisms and emerging concepts in cell signaling. , 2005, Free radical biology & medicine.

[42]  G. Salvesen,et al.  XIAP inhibits caspase‐3 and ‐7 using two binding sites: evolutionarily conserved mechanism of IAPs , 2005, The EMBO journal.

[43]  Shinzaburo Noguchi,et al.  Prediction of docetaxel response in human breast cancer by gene expression profiling. , 2005, Journal of clinical oncology : official journal of the American Society of Clinical Oncology.

[44]  J. C. Tilak,et al.  Free radicals and antioxidants in human health: current status and future prospects. , 2004, The Journal of the Association of Physicians of India.

[45]  J. Charlot,et al.  Mitochondrial translocation of p53 and mitochondrial membrane potential (ΔΨm) dissipation are early events in staurosporine-induced apoptosis of wild type and mutated p53 epithelial cells , 2004, Apoptosis.

[46]  Dean P. Jones,et al.  Redox Potential of Human Thioredoxin 1 and Identification of a Second Dithiol/Disulfide Motif* , 2003, Journal of Biological Chemistry.

[47]  K. Tonissen,et al.  The thioredoxin-thioredoxin reductase system: over-expression in human cancer. , 2003, Anticancer research.

[48]  Elias S. J. Arnér,et al.  The Mammalian Cytosolic Selenoenzyme Thioredoxin Reductase Reduces Ubiquinone , 2003, The Journal of Biological Chemistry.

[49]  Mason R. Mackey,et al.  Bid, Bax, and Lipids Cooperate to Form Supramolecular Openings in the Outer Mitochondrial Membrane , 2002, Cell.

[50]  G. Powis,et al.  The redox protein thioredoxin-1 (Trx-1) increases hypoxia-inducible factor 1alpha protein expression: Trx-1 overexpression results in increased vascular endothelial growth factor production and enhanced tumor angiogenesis. , 2002, Cancer research.

[51]  A. Kong,et al.  Antioxidants and oxidants regulated signal transduction pathways. , 2002, Biochemical pharmacology.

[52]  B. Mignotte,et al.  Mitochondrial reactive oxygen species in cell death signaling. , 2002, Biochimie.

[53]  A. Holmgren,et al.  Thioredoxin alters the matrix metalloproteinase/tissue inhibitors of metalloproteinase balance and stimulates human SK-N-SH neuroblastoma cell invasion. , 2001, European journal of biochemistry.

[54]  D. Mustacich,et al.  The role of the redox protein thioredoxin in cell growth and cancer. , 2000, Free radical biology & medicine.

[55]  Y Li,et al.  [Mitochondria and apoptosis]. , 2000, Zhonghua yu fang yi xue za zhi [Chinese journal of preventive medicine].

[56]  T M Grogan,et al.  Thioredoxin, a putative oncogene product, is overexpressed in gastric carcinoma and associated with increased proliferation and increased cell survival. , 2000, Human pathology.

[57]  X. Liu,et al.  An APAF-1·Cytochrome c Multimeric Complex Is a Functional Apoptosome That Activates Procaspase-9* , 1999, The Journal of Biological Chemistry.

[58]  S. Srinivasula,et al.  Autoactivation of procaspase-9 by Apaf-1-mediated oligomerization. , 1998, Molecular cell.

[59]  Kohei Miyazono,et al.  Mammalian thioredoxin is a direct inhibitor of apoptosis signal‐regulating kinase (ASK) 1 , 1998, The EMBO journal.

[60]  J C Reed,et al.  IAPs block apoptotic events induced by caspase‐8 and cytochrome c by direct inhibition of distinct caspases , 1998, The EMBO journal.

[61]  L. Obeid,et al.  Thioredoxin Peroxidase Is a Novel Inhibitor of Apoptosis with a Mechanism Distinct from That of Bcl-2* , 1997, The Journal of Biological Chemistry.

[62]  Minoru Takagi,et al.  Induction of Apoptosis by ASK1, a Mammalian MAPKKK That Activates SAPK/JNK and p38 Signaling Pathways , 1997, Science.

[63]  J. Yodoi,et al.  Cellular levels of thioredoxin associated with drug sensitivity to cisplatin, mitomycin C, doxorubicin, and etoposide. , 1995, Cancer research.

[64]  P. Seglen,et al.  3-Methyladenine: specific inhibitor of autophagic/lysosomal protein degradation in isolated rat hepatocytes. , 1982, Proceedings of the National Academy of Sciences of the United States of America.

[65]  G. Di Trapani,et al.  Thioredoxin system inhibitors as mediators of apoptosis for cancer therapy. , 2009, Molecular nutrition & food research.

[66]  T. Hollister,et al.  A novel response of cancer cells to radiation involves autophagy and formation of acidic vesicles. , 2001, Cancer research.

[67]  K. Miyazaki,et al.  Elevated serum level of thioredoxin in patients with hepatocellular carcinoma. , 1998, Biotherapy.

[68]  T. Naoe,et al.  In vitro studies on cellular and molecular mechanisms of arsenic trioxide (As2O3) in the treatment of acute promyelocytic leukemia: As2O3 induces NB4 cell apoptosis with downregulation of Bcl-2 expression and modulation of PML-RAR alpha/PML proteins. , 1996, Blood.

[69]  A. Holmgren,et al.  Thioredoxin and thioredoxin reductase. , 1995, Methods in enzymology.

[70]  L. B. Chen,et al.  Mitochondrial membrane potential monitored by JC-1 dye. , 1995, Methods in enzymology.

[71]  A. Holmgren,et al.  [21] Thioredoxin and thioredoxin reductase , 1995 .