Methylation and Loss of Heterozygosity in Human Gastric Is a Tumor Suppressor Gene Inactivated by Lysyl Oxidase
نویسندگان
چکیده
Lysyl oxidase (LOX) and HRAS-like suppressor (HRASLS) are silenced in human gastric cancers and are reported to have growth-suppressive activities in ras-transformed mouse/rat fibroblasts. Here, we analyzed whether or not LOX and HRASLS are tumor suppressor genes in human gastric cancers. Loss of heterozygosity and promoter methylation of LOX were detected in 33% (9 of 27) and 27% (26 of 96) of gastric cancers, respectively. Biallelic methylation and loss of heterozygosity with promoter methylation were also demonstrated in gastric cancers. Silencing of LOX was also observed in colon, lung, and ovarian cancer cell lines. As for mutations, only one possible somatic mutation was found by analysis of 96 gastric cancer samples and 58 gastric and other cancer cell lines. When LOX was introduced into a gastric cancer cell line, MKN28, in which LOX and HRASLS were silenced, it reduced the number of anchorage-dependent colonies to 57 to 61%, and the number of anchorage-independent colonies to 11 to 23%. Sizes of tumors formed in nude mice were reduced to 19 to 26%. Growth suppression in soft agar assay was also observed in another gastric cancer cell line, KATOIII. On the other hand, neither loss of heterozygosity nor a somatic mutation was detected in HRASLS, and its introduction into MKN28 did not suppress the growth in vitro or in vivo. These data showed that LOX is a tumor suppressor gene inactivated by methylation and loss of heterozygosity in gastric cancers, and possibly also in other cancers.
منابع مشابه
Lysyl oxidase is a tumor suppressor gene inactivated by methylation and loss of heterozygosity in human gastric cancers.
Lysyl oxidase (LOX) and HRAS-like suppressor (HRASLS) are silenced in human gastric cancers and are reported to have growth-suppressive activities in ras-transformed mouse/rat fibroblasts. Here, we analyzed whether or not LOX and HRASLS are tumor suppressor genes in human gastric cancers. Loss of heterozygosity and promoter methylation of LOX were detected in 33% (9 of 27) and 27% (26 of 96) of...
متن کاملTwo Steps Methylation Specific PCR for Assessment of APC Promoter Methylation in Gastric Adenocarcinoma
Gastric Cancer (GC) is the second most common cancer in the world and a leading cause of cancer-related mortality. Methylation of promoter CpG islands (CGIs) belonging to tumor suppressor genes causes transcriptional silencing of their corresponding genes leading to carcinogenesis and other disorders. Adenomatous Polyposis Coli (APC) a tumor suppressor gene is inactivated by methylation of prom...
متن کاملPromoter hypermethylation of KLOTHO; an anti-senescence related gene in colorectal cancer patients of Kashmir valley
Hypermethylation of CpG islands located in the promoter regions of genes is a major event in the development of the majority of cancer types, due to the subsequent aberrant silencing of important tumor suppressor genes. KLOTHO; a novel gene associated primarily with suppressing senescence has been shown to contribute to tumorigenesis as a result of its impaired function. Recently the relevance ...
متن کاملHypermethylation of E-Cadherin and Estro-gen Receptor- Gene Promoter and Its Association with Clinicopathological Features of Breast Cancer in Iranian Patients
Background: Aberrant methylation of cytosine-guanine dinucleotide islands leads to inactivation of tumor suppressor genes in breast cancer. Tumor suppressor genes are unmethylated in normal tissue and often become hypermethylated during tumor formation, leading to gene silencing. We investigated the association between E-cadherin (CDH1) and estrogen receptor-α (ESRα) gene promoter methylation a...
متن کاملE-cadherin Promoter Methylation Comparison and Correlation with the Pathological Features of the Squamous Cell Carcinoma of Esophagus in the High Risk Region
E-cadherin is among tumor suppressor genes which mostly subjects to the down-regulation in squamous cell carcinoma of esophagus (SCCE). The gene is tightly associated with the tumor invasion and metastasis in multiple human cancers, especially SCCE. CpG islands’ methylation in the promoter region of E-cadherin is among the mechanisms that have been suggested for the E-cadherin silencing, howeve...
متن کامل