Expression of circadian clock genes in abdominal malignant tumor

QIU Mengjun; XIONG Zhifan; HE Xiaoxiao; BI Ningrui; WANG Mengmeng; YANG Shengli

doi:10.3969/j.issn.1002-266X.2018.48.004

Abstract：Objective To explore the expression differences of clock genes in the abdominal malignant tumors.Methods The RNA-Seq expression of 14 kinds of clock genes in six abdominal malignant tumors and adjacent normal tissues (liver, gastric, pancreatic, kidney, rectal, and colon cancer) from the Cancer Genome Atlas (TCGA) database was integrated and evaluated to observe the differential expression of clock genes.We used the software edgeR in Bioconductor to standardize the RNA-Seq data.ResultsFourteen clock genes were significantly lowly expressed in the cancer tissues of six abdominal malignant tumors.Compared with the adjacent normal tissues, the expression levels of Cry2, CLOCK, Timeless, NPAS2, NR1D1, DEC1-2, and RORA were significantly lower in the liver cancer tissues (all P＜0.05).Compared with the adjacent normal tissues, the expression levels of Per1-2, Cry1-2, CLOCK, Timeless, NPAS2, NR1D1-2, DEC2, and RORA were significantly lower in the kidney cancer tissues (all P＜0.05).Compared with adjacent normal tissues, the expression levels of Per1-3, Cry1-2, Timeless, BMAL1, NR1D2, DEC1-2, and RORA were significantly lower in the colon cancer tissues (all P＜0.05).Compared with adjacent normal tissues, the expression levels of Per1, Per3, Cry1-2, CLOCK, BMAL1, NPAS2, NR1D1, DEC2, and RORA were significantly lower in rectal cancer tissues (all P＜0.05).Compared with the adjacent normal tissues, the expression levels of Per1, Per3, Cry2, CLOCK, Timeless, BMAL1, and NPAS2 were significantly lower in the gastric cancer tissues (all P＜0.05).ConclusionDifferent clock genes are expressed differently in different abdominal malignant tumors.