Combination of 13 cis-retinoic acid and tolfenamic acid induces apoptosis and effectively inhibits high-risk neuroblastoma cell proliferation.
Chemotherapeutic regimens used for the treatment of Neuroblastoma (NB) cause long-term side effects in pediatric patients. NB arises in immature sympathetic nerve cells and primarily affects infants and children. A high rate of relapse in high-risk neuroblastoma (HRNB) necessitates the development of alternative strategies for effective treatment. This study investigated the efficacy of a small molecule, tolfenamic acid (TA), for enhancing the anti-proliferative effect of 13 cis-retinoic acid (RA) in HRNB cell lines. LA1-55n and SH-SY5Y cells were treated with TA (30μM) or RA (20μM) or both (optimized doses, derived from dose curves) for 48h and tested the effect on cell viability, apoptosis and selected molecular markers (Sp1, survivin, AKT and ERK1/2). Cell viability and caspase activity were measured using the CellTiter-Glo and Caspase-Glo kits. The apoptotic cell population was determined by flow cytometry with Annexin-V staining. The expression of Sp1, survivin, AKT, ERK1/2 and c-PARP was evaluated by Western blots. The combination therapy of TA and RA resulted in significant inhibition of cell viability (p<0.0001) when compared to individual agents. The anti-proliferative effect is accompanied by a decrease in Sp1 and survivin expression and an increase in apoptotic markers, Annexin-V positive cells, caspase 3/7 activity and c-PARP levels. Notably, TA+RA combination also caused down regulation of AKT and ERK1/2 suggesting a distinct impact on survival and proliferation pathways via signaling cascades. This study demonstrates that the TA mediated inhibition of Sp1 in combination with RA provides a novel therapeutic strategy for the effective treatment of HRNB in children.
Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Institute of Cancer Research, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States.
Sagar
S
Shelake
Arnold Palmer Hospital for Children, Orlando, FL 32806, United States.
Don
D
Eslin
Arnold Palmer Hospital for Children, Orlando, FL 32806, United States.
Robert M
RM
Sutphin
Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Institute of Cancer Research, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States.
Umesh T
UT
Sankpal
Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States.
Anmol
A
Wadwani
Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States.
Laura E
LE
Kenyon
Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Institute of Cancer Research, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States.
Leslie
L
Tabor-Simecka
Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Institute of Cancer Research, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Cook Children's Medical Center, Fort Worth, TX 76104, United States.
W Paul
WP
Bowman
Institute of Cancer Research, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Department of Molecular & Medical Genetics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States.
Jamboor K
JK
Vishwanatha
Department of Pediatrics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Texas College of Osteopathic Medicine, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Institute of Cancer Research, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States; Department of Molecular & Medical Genetics, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, United States. Electronic address: riyaz.basha@unthsc.edu.
Riyaz
R
Basha
D000704:Analysis of Variance; D017304:Annexin A5 / Q000378:metabolism; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D000971:Antineoplastic Combined Chemotherapy Protocols; D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006801:Humans; D015474:Isotretinoin / Q000494:pharmacology*; D009447:Neuroblastoma / Q000473:pathology; D013723:Teratogens / Q000494:pharmacology*; D013997:Time Factors; D062367:ortho-Aminobenzoates / Q000494:pharmacology*
D017304:Annexin A5; D000894:Anti-Inflammatory Agents, Non-Steroidal; D013723:Teratogens; D062367:ortho-Aminobenzoates; C009500:tolfenamic acid; D020169:Caspases; D015474:Isotretinoin
Chemotherapy; Infants; Neuroblastoma; Retinoic acid; Sympathetic nervous system; Tolfenamic acid