Expression of CLEC4G in liver disease and its correlation with hepatocellular carcinoma

Abstract

Objective To investigate the expression level of C-type lectin domain family 4 member G (CLEC4G) in liver disease tissues and its correlation with the clinicopathological characteristics of hepatocellular carcinoma (HCC) patients. Methods The cancer tissue and the corresponding adjacent tissues (at least 2 cm from the edge of the cancer tissue), cut in surgeries from January to December in 2019, of 40 HCC patients in Zhuzhou Central Hospital, as well as 10 normal liver tissue samples (seen as far away as possible from the edge of the cancer tissue with naked eyes) and 10 liver cirrhosis samples were analyzed retrospectively. The tumor genome atlas (TCGA) database was used to screen the HCC transcriptome data sets, and bioinformatics methods were used to make expression heat maps and box maps which can help analyze the difference of CLEC4G in cancer and adjacent tissues. The mRNA expression level of CLEC4G was detected by conducting real-time fluorescence quantitative PCR (qRT-PCR), and the protein expression level of CLEC4G was detected by immunohistochemistry (IHC). The measurement data were expressed as mean±standard deviation (Mean±SD). Group t test was used for inter-group comparison. The counting information was expressed as a percentage (%). The χ2 test was adopted to analyze the correlation between CLEC4G expression level and the clinicopathological features of patients. Results The expression level of CLEC4G in cancer tissues was significantly decreased in heat map compared with that in adjacent tissues. In the box figure, the relative expression of CLEC4G mRNA in the cancer tissues was (82.5±18.9) and (3 354.4±296.2) in paracancer tissues, with statistically significant difference (P<0.001). Respectively, qRT-PCR and IHC showed that mRNA of CLEC4G were abundant in normal liver tissues (3 301.3±286.4), while they were very little in liver cancer tissues (63.6±32.9), significantly decreasing in liver cirrhosis (1 742.6±208.7) and paracancer tissues (1 553.2±249.9), with statistically significant difference (P<0.001). Moreover, low CLEC4G expression level was associated with tumor vascular metastasis in HCC patients. Conclusions CLEC4G is highly expressed in normal liver tissue, but with the progression of malignant liver disease, it is significantly decreased with little expression in HCC tissue. It can be expected to be a good marker for the pathological diagnosis of HCC. Key words: Carcinoma, hepatocellular; Liver cirrhosis; Neoplasms, vascular tissue; Liver tissue