Objective To obtain the full-length gene and functional domains of FXYD6 gene which is a cholangiocarcinoma related gene. Methods A new strategy with the integration of bioinformatics and molecular biology was used. Bioinformatical methods were used to analyze the full-length sequence, and to predict the functional domains of its protein. And the full-length sequence of FXYD6 was isolated by polymerase chain reaction from fetal hepatic, brain and spleen cDNA libraries, and then cloned in pGEM-T vector for sequence analyzing. Goldkey Sequence Analyzing Software was used to analyze the sequence of candidate domain without signal peptide.Results The full-length sequence of FXYD6 was isolated by Touch-down PCR from fetal hepatic and brain cDNA library, but was not from spleen cDNA library. The open reading frame Finder software was used in the National Center for Biotechnology Information website to find the most probable encoding regions of FXYD6 gene. And the +1 phase was selected as the template sequence, from 67 bp to 354 bp, to predict the functional domains by Goldkey Sequence Analyzing Software. The signal peptide was located from 1 amino acid (aa) to 17 aa， and the main domain was composed from 18 aa to 34 aa. The region between 35 aa and 57 aa was the transmembrane region. The FHYD peptide chain was highly conserved amino acids. Conclusion The study of full-length cDNA cloning of FXYD6 gene and its functional domains provides the basis for understanding the relationship between the structure and function of FXYD6. More work shall be performed on FXYD6 protein and its influence on the mechanism of cholangiocarcinoma.
ObjectiveTo detect expression of FXYD6 protein in hilar cholangiocarcinoma tissues and explore its significances. MethodsThe expressions of FXYD6 protein in the 58 hilar cholangiocarcinoma tissues and 30 normal bile duct tissues adjacent to cancer were detected by strept avidin-biotin complex (SABC) immunohistochemistry. The relation between FXYD6 protein expression and biological characteristics of patient with hilar cholangiocarcinoma was analyzed. ResultsThe positive rate of FXYD6 protein expression in the hilar cholangiocarcinoma tissues was significantly higher than that in the normal bile duct tissues adjacent to cancer[75.9% (44/58) versus 33.3% (10/30), χ2=15.084, P=0.000]. Furthermore, the positive rate of FXYD6 protein expression in the well and moderately differentiated hilar cholangiocar-cinoma tissue was significantly higher than that in the poorly differentiated hilar cholangiocarcinoma [85.4% (35/41) versus 52.9% (9/17), χ2=5.243, P=0.022], which was not related to the gender (χ2=0.000, P=1.000), age (χ2=1.248, P=0.264), T stage (χ2=0.466, P=0.495), lymph node metastasis (χ2=0.357, P=0.550), pathological stage (χ2=0.005, P=0.944), and perineural invasion (χ2=3.016, P=0.082). Conclustion The positive rate of FXYD6 protein expression is associated with differentiation of hilar cholangiocarcinoma, which might be a new biomarker of it.
ObjectiveTo detect the expression of FXYD domain-containing ion transport regulator 6 (FXYD6) protein in hepatocellular carcinoma tissues and the corresponding paracancerous liver tissues, and to explore the clinical significance of FXYD6 protein expression in hepatocellular carcinoma.MethodsEighty hepatocellular carcinoma tissues and the corresponding 40 paracancerous tissues were retrospectively collected in Cangzhou Central Hospital from March 2012 to January 2018, and the expression of FXYD6 protein was examined in these tissues by strept avidin-biotin complex (SABC) immunohistochemistry. We analyzed the relationship between the expression of FXYD6 protein and clinicopathological characteristics of the patients with hepatocellular carcinoma, and the relationship between the expression of the protein and early recurrence or overall survival.ResultsThe positive expression rate of FXYD6 protein was statistically higher in hepatocellular carcinoma tissues than that in the corresponding paracancerous tissues [77.5% (62/80) vs. 40.0% (16/40), P<0.001]. Its expression in hepatocellular carcinoma was not related with gender, age, histological differentiation, tumor maximum diameter, tumor number, AFP concentration in serum, and HBV or HCV infection (P>0.05), but with integrity of tumor capsule, microvascular invasion, and tumor stage (P<0.05). The positive FXYD6 protein expression group had a significantly higher recurrence rate than that of the negative FXYD6 protein expression group [53.2% (33/62) vs. 16.7% (3/18), P=0.006]. However, multivariate analysis results showed that high FXYD6 protein expression was not a risk factor for early relapse (P=0.422). The positive FXYD6 protein expression group had a significantly shorter postoperative survival than the negative FXYD6 expression group ( P=0.043). However, multivariate analysis results showed high FXYD6 protein expression was not a risk factor for overall survival (P=0.754).ConclusionsFXYD6 protein was expressed abnormally in hepatocellular carcinoma tissues, which might be involved in the carcinogenesis and the progression of hepatocellular carcinoma. It might be a poor prognostic factor for patient with hepatocellular carcinoma.