Gill Kamaldeep, Singh Abhay K, Kapoor Vaishali, Nigam Lokesh, Kumar Rahul, Holla Prasida, Das Satya N, Yadav Savita, Subbarao Naidu, Mohanti Bidhu K, Dey Sharmistha
Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
Biochim Biophys Acta. 2013 Mar;1830(3):2763-9. doi: 10.1016/j.bbagen.2012.12.001.
The p38alpha MAP kinase pathway is involved in inflammation, cell differentiation, growth, apoptosis and production of pro-inflammatory cytokines TNF-alpha and IL-1beta. The overproduction of these cytokines plays an important role in cancer. The aim of this work was to design a peptide inhibitor on the basis of structural information of the active site of p38alpha.
A tetrapeptide, VWCS as p38alpha inhibitor was designed on the basis of structural information of the ATP binding site by molecular modeling. The inhibition study of peptide with p38alpha was performed by ELISA, binding study by Surface Plasmon Resonance and anti-proliferative assays by MTT and flow cytometry.
The percentage inhibition of designed VWCS against pure p38alpha protein and serum of HNSCC patients was 70.30 and 71.5%, respectively. The biochemical assay demonstrated the K(D) and IC50 of the selective peptide as 7.22 x 10(-9) M and 20.08 nM, respectively. The VWCS as inhibitor significantly reduced viability of oral cancer KB cell line with an IC50 value of 10 microM and induced apoptosis by activating Caspase 3 and 7.
VWCS efficiently interacted at the ATP binding pocket of p38alpha with high potency and can be used as a potent inhibitor in case of HNSCC.
VWCS can act as an anticancer agent as it potentially inhibits the cell growth and induces apoptosis in oral cancer cell-line in a dose as well as time dependent manner. Hence, p38alpha MAP kinase inhibitor can be a potential therapeutic agent for human oral cancer.
p38α丝裂原活化蛋白激酶（MAPK）信号通路参与炎症反应、细胞分化、生长、凋亡以及促炎细胞因子肿瘤坏死因子-α（TNF-α）和白细胞介素-1β（IL-1β）的产生。这些细胞因子的过度产生在癌症中起着重要作用。本研究旨在基于p38α活性位点的结构信息设计一种肽抑制剂。
通过分子模拟，基于ATP结合位点的结构信息设计了一种四肽VWCS作为p38α抑制剂。采用酶联免疫吸附测定（ELISA）对该肽与p38α的抑制作用进行研究，利用表面等离子体共振技术进行结合研究，并通过MTT法和流式细胞术进行抗增殖测定。
设计的VWCS对纯p38α蛋白和头颈部鳞状细胞癌（HNSCC）患者血清的抑制率分别为70.30%和71.5%。生化分析表明，该选择性肽的解离常数（K(D)）和半数抑制浓度（IC50）分别为7.22×10⁻⁹ M和20.08 nM。VWCS作为抑制剂可显著降低口腔癌KB细胞系的活力，IC50值为10 μM，并通过激活半胱天冬酶3和7诱导细胞凋亡。
VWCS能高效地与p38α的ATP结合口袋相互作用，具有高效力，可作为HNSCC的有效抑制剂。
VWCS可作为一种抗癌剂，因为它能以剂量和时间依赖性方式潜在地抑制口腔癌细胞系的生长并诱导细胞凋亡。因此，p38α MAPK抑制剂可能是治疗人类口腔癌的潜在药物。
