Sarma P P, Dutta D, Mirza Z, Saikia K Kr, Baishya B Kr
Department of Bioengineering and Technology, Gauhati University, Guwahati, 781014 India.
Department of Neurosurgery, Gauhati Medical College and Hospital, Guwahati, 781026 India.
Mol Biol (Mosk). 2017 Mar-Apr;51(2):334-341. doi: 10.7868/S0026898417020185.
TP53 mutations play a significant role in glioma tumorigenesis. When located in in the DNA binding domain, these mutations can perturb p53 protein conformation and its function, often culminating in altered downstream signaling. Here we describe prevalent pattern of TP53 point mutations in a cohort of 40 glioma patients and show their relevance to gliomagenesis. Point mutations in exon 5-9 of TP53 gene were detected by DNA sequencing. Possible influence of identified mutations at the function of p53 was studied computationally and correlated with the survival. Point mutations in TP53 were detected in 10 glioma samples (25%), out of which 70% were from high grade glioma. A total of 19 TP53 point mutations were identified, out of which 42% were found to be in the DNA binding region of p53. Computational analysis predicted 87.5% of these mutations to be "probably damaging". In three patients with tumors possessing point mutations R273H, R248Q, Y163H and R175H and poor survival times, structural analysis revealed the nature of these mutations to be disruptive and associated with high risk for cancer progression. In high grade glioma, recurrent TP53 point mutations may be the key to tumor progression, thus, emphasizing their significance in gliomagenesis.
TP53突变在胶质瘤的肿瘤发生过程中起着重要作用。当这些突变位于DNA结合域时,会扰乱p53蛋白的构象及其功能,常常导致下游信号传导改变。在此,我们描述了40例胶质瘤患者队列中TP53点突变的普遍模式,并展示了它们与胶质瘤发生的相关性。通过DNA测序检测TP53基因第5至9外显子的点突变。通过计算机分析研究了已鉴定突变对p53功能的可能影响,并将其与生存率相关联。在10个胶质瘤样本(25%)中检测到TP53点突变,其中70%来自高级别胶质瘤。总共鉴定出19个TP53点突变,其中42%位于p53的DNA结合区域。计算机分析预测这些突变中有87.5%“可能具有破坏性”。在三名肿瘤具有R273H、R248Q、Y163H和R175H点突变且生存时间较短的患者中,结构分析显示这些突变具有破坏性,且与癌症进展的高风险相关。在高级别胶质瘤中,TP53反复出现的点突变可能是肿瘤进展的关键,因此,强调了它们在胶质瘤发生中的重要性。