Regional bias of tumor suppressor gene mutations of STARD8 and WNK2 in colon cancers.

StAR-related lipid transfer domain protein 8 (STARD8), encoding a Rho-GTPase-activating protein, and WNK2, encoding a serine/threonine kinase are candidate tumor suppressor genes (TSGs) in human cancers. Inactivation of these genes that would promote cancer pathogenesis is largely unknown in colon cancer (CC). Our study addressed to address whether STARD8 and WNK2 genes are mutated in CC.

Genes with dual proto-oncogene and tumor suppressor gene activities are frequently altered by protein losses in colon cancers.

Cancer genes are largely categorized into tumor suppressor gene (TSG) and proto-oncogene, but many have dual activities depending on the cellular context. In the present study, we analyzed DYRK1B, ESRP1, MTSS1, ADAMTS1, and INPP5F genes known to possess the dual activities in sporadic colon cancers (CCs). By the mutation analysis, we identified DYRK1B, ESRP1, MTSS1, ADAMTS1, and INPP5F frameshift mutations in 2, 2, 3, 3, and 1 CCs in instability-high (MSI-H) cases (1.

Concurrent inactivating mutations and expression losses of RGS2, HNF1A, and CAPN12 candidate tumor suppressor genes in colon cancers.

Microsatellite instability-high (MSI-H) colorectal cancer (CRC) is different from microsatellite stable (MSS) CRC concerning biological, and clinical features. In MSI-H CRCs, defects of mismatch repair genes produce increased mutation accumulation in repetitive DNA sequences. To see whether candidate tumor suppressor genes (TSGs) are altered in MSI-H CRC, we studied frameshift mutation and protein expression of candidate TSGs of RGS2, HNF1A, HNF1B, CAPN12, RCBTB2, ATE1, PKNOX1, and USP19.

Mutational Alterations of DNA Methylation-related Genes CTCF, ZFP57, and ATF7IP Genes in Colon Cancers.

Deregulations of DNA-methylation-related genes are common in cancers, but frameshift mutation status in colon cancer (CC) is unknown. Our study aims to assess whether CTCF, ZFP57, and ATF7IP genes in this category are mutated in CC. CTCF, ZFP57, and ATF7IP genes have repeat coding sequences, which are frequently deleted or duplicated in CC, harboring the phenotype of unstable or high microsatellite instability (MSI-H).

Somatic Mutation of Genes in Gastric and Colonic Cancers.

Nucleotide-binding and leucine-rich repeat protein (NLRP) genes are involved in inflammasome formation that plays a role in inflammation/host defense and cell death. Both cell death and inflammation are crucial for cancer development, but the roles of NLRPs in cancer are partially known. In this study, we analyzed mononucleotide repeats in coding sequences of and and found 1, 1, 1 and 8 frameshift mutation (s) in gastric (GC) and colonic cancers (CRC), respectively.

Mutation and expression alterations of histone methylation-related NSD2, KDM2B and SETMAR genes in colon cancers.

Epigenetic dysregulation is a hallmark of cancers, and examples of its cancer-associated expression and mutation alterations are rapidly growing. Histone methylation, a process by which methyl groups are transferred to amino acids of histone proteins, is crucial for the epigenetic gene regulation. NSD2 (nuclear receptor-binding SET domain protein 2) and SETMAR are epigenetic regulators for histone methylation.

Cancer-related SRCAP and TPR mutations in colon cancers.

Current information suggests that SRCAP, TPR and CEACAM5 genes have cancer-related activities, but their alteration status is not well identified in colon cancer (CC). In this study, we analyzed frameshift mutations of these genes in CCs according to the microsatellite instability (MSI) status (high MSI (MSI-H) and microsatellite stable (MSS) CCs). In addition, regional difference in frameshift mutations of SRCAP, TPR and CEACAM5 genes were studied in CCs.

Frameshift Mutations and Loss of Expression of CLCA4 Gene are Frequent in Colorectal Cancers With Microsatellite Instability.

Chloride channel calcium-activated (CLCA) genes encode regulators for chloride transport across the cell membrane. As for cancer development, some CLCA genes are considered putative tumor suppressor genes. The aim of this study was to explore whether CLCA4 gene would have mutations in its nucleotide repeats in colorectal cancer (CRC).

Somatic mutation and loss of expression of a candidate tumor suppressor gene TET3 in gastric and colorectal cancers.

Ten-eleven translocation 3 (TET3) is responsible for the DNA methylation and plays an important role in regulation of the gene expression. TET2, another TET, is frequently mutated in hematologic malignancies and considered a driver gene for leukemogenesis. TET3 mRNA downregulation has been identified in many solid cancers, suggesting its role as a candidate tumor suppressor gene (TSG).

Frameshift mutation of candidate tumor suppressor genes QK1 and TMEFF2 in gastric and colorectal cancers.

Background: Both QKI and TMEFF2 genes are considered putative tumor suppressor genes (TSGs). In gastric (GC) and colorectal (CRC) cancers, downregulation of their expressions is known to be frequent. However, QKI and TMEFF2 mutations that could potentially inactivate their functions are not reported in cancers.