ABSTRACT
PURPOSE: The p38 mitogen-activated protein kinase (MAPKs) play a crucial role in the production of pro-inflammatory cytokines and over-expression of it increase cytokines which promote cancer. Among four isoforms, p38α has been well studied in head and neck squamous cell carcinoma (HNSCC) and other cancers as a therapeutic target. p38δ has recently emerged as a potential disease-specific drug target. Elevated serum p38α level in HNSCC was reported earlier from our lab. This study aims to estimate the levels of p38 MAPK-isoforms in the serum of HNSCC and design peptide inhibitor targeting the same. MATERIALS AND METHODS: Levels of p38 MAPK isoforms in the serum of HNSCC and healthy controls were quantified by surface plasmon resonance technology. The peptide inhibitor for p38 MAPK was designed by molecular modeling using Grid-based Ligand Docking with Energetics tools and compared with known specific inhibitors. RESULTS: We have observed highly elevated levels of all four isoforms of p38 MAPK in serum of HNSCC patients compared to the control group. Further, serum p38α, p38ß, and p38δ levels were down regulated after therapy in follow-up patients, while p38γ showed no response to the therapy. Present study screened designed peptide WFYH as a specific inhibitor against p38δ. The specific inhibitor of p38δ was found to have no effect on p38α due to great structural difference at ATP binding pocket. CONCLUSION: In this study, first time estimated the levels of p38 MAPK isoforms in the serum of HNSCC. It can be concluded that p38 MAPK isoforms can be a diagnostic and prognostic marker for HNSCC and p38δ as a therapeutic target.
Subject(s)
Carcinoma, Squamous Cell/diagnosis , Mitogen-Activated Protein Kinase 13/antagonists & inhibitors , Peptide Fragments/chemical synthesis , Protein Kinase Inhibitors/chemical synthesis , Squamous Cell Carcinoma of Head and Neck/diagnosis , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/blood , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/metabolism , Cell Line, Tumor , Drug Design , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Male , Middle Aged , Mitogen-Activated Protein Kinase 11/blood , Mitogen-Activated Protein Kinase 11/chemistry , Mitogen-Activated Protein Kinase 12/blood , Mitogen-Activated Protein Kinase 12/chemistry , Mitogen-Activated Protein Kinase 13/blood , Mitogen-Activated Protein Kinase 13/chemistry , Mitogen-Activated Protein Kinase 14/blood , Mitogen-Activated Protein Kinase 14/chemistry , Models, Molecular , Molecular Docking Simulation , Peptide Fragments/chemistry , Peptide Fragments/pharmacology , Peptide Library , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Squamous Cell Carcinoma of Head and Neck/blood , Squamous Cell Carcinoma of Head and Neck/drug therapy , Squamous Cell Carcinoma of Head and Neck/metabolism , Surface Plasmon Resonance , Up-Regulation/drug effectsABSTRACT
Pancreatic cancer is very difficult to diagnose in its early stage. Molecular marker and imaging have not proven to be accurate modalities for screening of pancreatic cancer. This study aims to develop p38ß as a protein marker for pancreatic cancer and to design peptide inhibitor against the same. The serum p38ß level of pancreatic cancer (n = 35; 5.06 µg/mL) was twofold higher compared to that of the chronic pancreatitis (n = 10; 2.92 µg/mL) and matched normal control (n = 10; 2.86 µg/ml) (p < 0.0005). Peptide inhibitors were designed to inhibit the activity of p38ß and the kinetic assay had shown the dissociation constant, (K(D)) to be 3.16 × 10(-8) M and IC(50), 25 nM by Surface Plasmon Resonance (SPR) and Enzyme-Linked Immunosorbent Assay (ELISA), respectively. The peptide inhibitor also significantly reduced viability and induced cytotoxicity in Human Pancreatic carcinoma epithelial-like cell line (PANC-1) cells.
