title: Targeting specificity protein 1 transcription factor and survivin using tolfenamic acid for inhibiting Ewing sarcoma cell growth.
abstract: Transcription factor Specificity protein 1 (Sp1) and its downstream target survivin (inhibitor of apoptosis protein), play major roles in the pathogenesis of various cancers. Ewing Sarcoma (ES) is a common soft tissue/bone tumor in adolescent and young adults. Overexpression of survivin is also linked to the aggressiveness and poor prognosis of ES. Small molecule Tolfenamic acid (TA) inhibits Sp1 and survivin in cancer cells. In this investigation, we demonstrate a strategy to target Sp1 and survivin using TA and positive control Mithramycin A (Mit) to inhibit ES cell growth. Knock down of Sp1 using small interfering RNA (siRNA) resulted in significant (p < 0.05) inhibition of CHLA-9 and TC-32 cell growth as assessed by CellTiter-Glo assay kit. TA or Mit treatment caused dose/time-dependent inhibition of cell viability, and this inhibition was correlated with a decrease in Sp1 and survivin protein levels in ES cells. Quantitative PCR results showed that Mit treatment decreased the mRNA expression of both survivin and Sp1, whereas TA diminished only survivin but not Sp1. Proteasome inhibitor restored TA-induced inhibition of Sp1 protein expression suggesting that TA might cause proteasome-dependent degradation. Gel shift assay using ES cell nuclear extract and biotinylated Sp1 consensus oligonucleotides confirmed that both TA and Mit decreased DNA-binding activity of Sp1. These results demonstrate that both Mit and TA reduce expression of Sp1 and survivin, disrupt Sp1 DNA-binding and inhibit ES cell proliferation. This investigation suggests that targeting Sp1 and survivin could be an effective strategy for inhibiting ES cell growth.
authors.affiliation: Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.
authors.forename: Sagar
authors.initials: S
authors.lastname: Shelake
authors.affiliation: Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.|Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.
authors.forename: Umesh T
authors.initials: UT
authors.lastname: Sankpal
authors.affiliation: Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.|Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.|Hematology and Oncology, Cook Children's Medical Center, Fort Worth, TX, 76104, USA.
authors.forename: W
authors.initials: W
authors.lastname: Paul Bowman
authors.affiliation: Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Wise
authors.affiliation: Hematology and Oncology, Cook Children's Medical Center, Fort Worth, TX, 76104, USA. Anish.Ray@cookchildrens.org.
authors.forename: Anish
authors.initials: A
authors.lastname: Ray
authors.affiliation: Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA. riyaz.basha@unthsc.edu.|Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA. riyaz.basha@unthsc.edu.|Hematology and Oncology, Cook Children's Medical Center, Fort Worth, TX, 76104, USA. riyaz.basha@unthsc.edu.
authors.forename: Riyaz
authors.initials: R
authors.lastname: Basha
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D012512:Sarcoma, Ewing / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D016329:Sp1 Transcription Factor / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D000077022:Survivin; D062367:ortho-Aminobenzoates / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D016329:Sp1 Transcription Factor; C108209:SP1 protein, human; D000077022:Survivin; D062367:ortho-Aminobenzoates; C009500:tolfenamic acid
keywords: Ewing sarcoma; Mithramycin; Sp1; Survivin; Targeted therapy; Tolfenamic acid