Combinatorial approach of in silico and in vitro evaluation of MLH1 variant associated with Lynch syndrome like metastatic colorectal cancer
Authors: Wenjing Sun
Chunhui Zhang
Siqi Zhu
Yusi Wang
Komal Saleem
Qian Qin
Xueyuan Jia
Wei Ji
Songbin Fu
Lidan Xu
Kexian Dong
Jie Wu
Tahir Zaib
Hanfei Yu
Shuhan Si
Journal: Bioscience reports (2020)
Discipline: MOLECULAR BIOLOGY & GENETICS
Keywords: Colorectal cancer; In silico tools; In vitro analysis; Lynch syndrome; MLH1
Affiliations: Laboratory of Medical Genetics, Harbin Medical University, Harbin 150081, China., Key Laboratory of Preservation of Human Genetics Resources and Disease Control in China, Harbin Medical University, Ministry of Education, Harbin 150081, China., Department of Gastrointestinal Medical Oncology, Harbin Medical University Cancer Hospital, Harbin 150040, China.

Abstract:  Colorectal cancer (CRC) is the third most developing cancer worldwide and Lynch syndrome (LS) accounts for 3-4% of CRC. Genetic alteration in any of DNA mismatch repair (MMR) gene is the major cause of LS that disrupt the normal upstream and downstream MMR events. Germline mutation of MLH1 in heterozygous state have an increased risk for CRC. Defective MMR pathway mostly results in microsatellite instability (MSI) that occurs in high percentage of CRC associated tumors. Here, we reported a patient with LS like metastatic CRC (mCRC) associated with other related cancers. Whole exome sequencing (WES) of the proband was performed to identify potential causative gene. Genetic screening validated by Sanger sequencing identified a heterozygous missense mutation in exon 12 of MLH1 (c.1151T&gt;A, p.V384D). The clinical significance of identified variant was elucidated on the basis of clinicopathological data, computational predictions and various in vitro functional analysis. In silico predictions classified the variant to be deleterious and evolutionary conserved. In vitro functional studies revealed a significant decrease in protein expression because of stability defect leading to loss of MMR activity. Mutant residue found in MutL transducer domain of MLH1 that localized in the nucleus but translocation was not found to be significantly disturbed. In conclusion, our study give insight into reliability of combinatorial prediction approach of in silico and in vitro expression analysis. Hence, we highlighted the pathogenic correlation of MLH1 variant with LS associated CRC as well as help in earlier diagnosis and surveillance for improved management and genetic counselling. 

Retracted: No

PubPeer comments:
 There is a duplication in Figure 3 Panel A: ![file] , 
 Thank you for reading carefully. We are very sorry for that. We will take it seriously and deal with it properly. , 
 u201cThe Editorial Office has been made aware of potential issues surrounding the scientific validity of this paper, hence has issued an expression of concern to notify readers whilst the Editorial Office investigates.u201c https: portlandpress.com bioscirep article 40 6 BSR-20200225_EOC 225479 Expression-of-Concern-Combinatorial-approach-of-in , 
 This article has now been retracted. Here is the retraction notice:  This Retraction follows an Expression of Concern relating to this article previously published by Portland Press. This article is being retracted from Bioscience Reports at the request of the authors following receipt of a notification from a reader, alerting the authors to duplications in panels of Figure 3A. The authors are unable to correct the article and wish to retract the article. The Editor-in-Chief and Editorial Board agree with the retraction. https: portlandpress.com bioscirep article 40 7 BSR-20200225_RET 225675 Retraction-Combinatorial-approach-of-in-silico-and ,