Expression Profile of MAGE-B1 Gene and Its Hypomethylation Activation in Colon Cancer

Expression pattern analysis of the MAGE family genes in breast cancer patients and hypomethylation activation in the MCF-7 cells

Melanoma antigen gene (MAGE) families are cancer-testis genes that normally show expression in the testes. However, their expressions have been linked with various types of human cancers, including BC. Therefore, the primary purposes of the present research were to assess the expression of MAGE-A, -B, and -C genes in Saudi female patients with BC and determine their regulation via the epigenetic mechanism. Ten BC samples were analyzed for the expression levels of nine MAGE-A genes, six MAGE-B genes, and three MAGE-C genes using the RT-PCR technique. All 18 evaluated genes except for MAGE-A1, -A3, -A4, and -B5 showed weak band expressions in some BC specimens. MAGE-A6 and -B2 were expressed in 40 % of the BC tissue samples, and MAGE-A9, -A10, and -B6 were expressed in 30 %. The lowest expression levels were found for MAGE-A11, -B1, -B3, -B4, -C1, and -C2 in 10 % of the BC specimens and for MAGE-A9,--B2, and --C3 in 20 % of the samples. The most frequently expressed gene was MAGE-A8 (found in 70 % of the BC samples), which suggests that it may serve as - a marker for screening of BC. In vitro treatment, the 5-aza-2'-deoxycytidine agent led to a significant rise in mRNA expressions for all tested genes related to the MAGE-A family, except for MAGE-A10. By contrast, among the genes in the MAGE-B and -C families, only MAGE-B1 and -C2 exhibited detectable mRNA expression levels after treatment.

FTHL17, PRM2, CABYR, CPXCR1, ADAM29, and CABS1 are highly expressed in colon cancer patients and are regulated in vitro by epigenetic alterations

Background

Colon cancer is a serious public health issue and a major cause of cancer-related mortality worldwide, including Saudi Arabia. Knowledge of genes associated with colon cancer development and progression is essential for identifying new cancer-specific biomarkers to improve the diagnosis of colon cancer.

Methods

The expression levels of FTHL17, PRM2, CABYR, CPXCR1, ADAM29, and CABS1 in 15 adjacent colon cancer and normal colon tissue samples from male patients were investigated using reverse transcription polymerase chain reaction (RT-PCR) and quantitative RT-PCR (qRT-PCR) assays. qRT-PCR analysis was also used to determine whether reducing DNA methyltransferase (via 5-aza-2'-deoxycytidine treatment) or histone deacetylation (via trichostatin treatment) increased the expression levels of the tested genes.

Results

The analysis of the 15 colon cancer and adjacent normal colon tissue samples revealed that all six genes were expressed in both groups, but their expression levels were significantly higher in the colon cancer group. Furthermore, the mRNA expression levels of the FTHL17, PRM2, CABYR, CPXCR1, and ADAM29 genes were considerably upregulated after treatment of HCT116 and Caco-2 cells with 5-aza-2'-deoxycytidine and trichostatin. However, the CABS1 gene was activated only with trichostatin treatment.

Conclusions

The findings of this study suggest that FTHL17, PRM2, CABYR, CPXCR1, ADAM29, and CABS1 are suitable candidate biomarkers of colon cancer and their expressions are regulated by hypomethylation and hyperacetylation.

Retracted: Expression Profile of MAGE-B1 Gene and Its Hypomethylation Activation in Colon Cancer

[This retracts the article DOI: 10.1155/2022/6066567.].

HSPB6 Is Depleted in Colon Cancer Patients and Its Expression Is Induced by 5-aza-2'-Deoxycytidine In Vitro

Background and Objectives: Colon cancer (CC) is the second most common cancer in Saudi Arabia, and the number of new cases is expected to increase by 40% by 2040. Sixty percent of patients with CC are diagnosed in the late stage, causing a reduced survival rate. Thus, identifying a new biomarker could contribute to diagnosing CC in the early stages, leading to delivering better therapy and increasing the survival rate. Materials and Methods: HSPB6 expression was investigated in extracted RNA taken from 10 patients with CC and their adjacent normal tissues, as well as in DMH-induced CC and a colon treated with saline taken from a male Wistar rat. Additionally, the DNA of the LoVo and Caco-2 cell lines was collected, and bisulfite was converted to measure the DNA methylation level. This was followed by applying 5-aza-2'-deoxycytidine (AZA) to the LoVo and Caco-2 cell lines for 72 h to see the effect of DNA methylation on HSPB6 expression. Finally, the GeneMANIA database was used to find the interacted genes at transcriptional and translational levels with HSPB6. Results: We found that the expression of HSPB6 was downregulated in 10 CC tissues compared to their adjacent normal colon tissues, as well as in the in vivo study, where its expression was lower in the colon treated with the DMH agent compared to the colon treated with saline. This suggests the possible role of HSPB6 in tumor progression. Moreover, HSPB6 was methylated in two CC cell lines (LoVo and Caco-2), and demethylation with AZA elevated its expression, implying a mechanistic association between DNA methylation and HSPB6 expression. Conclusions: Our findings indicate that HSPB6 is adversely expressed with tumor progression, and its expression may be controlled by DNA methylation. Thus, HSPB6 could be a good biomarker employed in the CC diagnostic process.

Higher Expression Levels of SSX1 and SSX2 in Patients with Colon Cancer: Regulated In Vitro by the Inhibition of Methylation and Histone Deacetylation

Background and Objectives: Colon cancer (CC) has a high mortality rate and is often diagnosed at an advanced stage in Saudi Arabia. Thus, the identification and characterization of potential new cancer-specific biomarkers are imperative for improving the diagnosis of CC by detecting it at an early stage. Cancer-testis (CT) genes have been identified as potential biomarkers for the early diagnosis of various cancers. Among the CT genes are those belonging to the SSX family. In order to assess the usefulness of SSX family genes as cancer biomarkers for the detection of early-stage CC, the goal of this research was to validate the expressions of these genes in patients with CC and in matched patients with normal colons (NCs). Materials and Methods: RT-PCR assays were used to analyze the SSX1, SSX2, and SSX3 family gene expression levels in 30 neighboring NC and CC tissue samples from male Saudi patients. Epigenetic alterations were also tested in vitro using qRT-PCR analysis to determine whether reduced DNA methyltransferase or histone deacetylation could stimulate SSX gene expression via 5-aza-2'-deoxycytidine and trichostatin treatments, respectively. Results: The RT-PCR results showed SSX1 and SSX2 gene expression in 10% and 20% of the CC tissue specimens, respectively, but not in any of the NC tissue specimens. However, no SSX3 expression was detected in any of the examined CC or NC tissue samples. In addition, the qRT-PCR results showed significantly higher SSX1 and SSX2 expression levels in the CC tissue samples than in the NC tissue samples. The 5-aza-2'-deoxycytidine and trichostatin treatments significantly induced the mRNA expression levels of the SSX1, SSX2, and SSX3 genes in the CC cells in vitro. Conclusions: These findings suggest that SSX1 and SSX2 are potentially suitable candidate biomarkers for CC. Their expressions can be regulated via hypomethylating and histone deacetylase treatments, subsequently providing a potential therapeutic target for CC.