Dyskerin expression in human fetal, adult and neoplastic intrahepatic bile ducts: correlations with cholangiocarcinoma aggressiveness

Evidence from a meta-analysis for the prognostic and clinicopathological importance of DKC1 in malignancies

Aim: We conducted a meta-analysis to evaluate the prognostic and clinicopathological relevance of DKC1 in various cancers. Methods: We searched Web of Science, Embase, PubMed, Wanfang and CNKI. Stata SE15.1 was used to calculate the hazard ratio and relative risk with 95% CIs to assess the possible correlations between DKC1 expression levels and overall and disease-free survival, as well as with clinicopathological parameters. Results: We included nine studies, with a total of 2574 patients. There was a meaningful link between elevated DKC1 and poorer disease-free (p < 0.001) and overall survival (p < 0.001). Also, it was linked to advanced tumor node metastasis stage (p = 0.005). Conclusion: High DKC1 expression was predictive of worse prognosis and poorer clinicopathological parameters.

MRPL27 contributes to unfavorable overall survival and disease-free survival from cholangiocarcinoma patients

Objective: This study aimed to investigate the roles of MRPL27 in survival from cholangiocarcinoma patients in The Cancer Genome Atlas (TCGA) database. Methods: In TCGA-CHOL profile, MRPL27 gene expression and clinical data were obtained. Cox regression models were used to evaluate the potential links between MRPL27 and cholangiocarcinoma survival. Enrichment analysis of MRPL27 was conducted in Metascape and Gene Set Enrichment Analysis (GSEA) databases. Results: 36 cholangiocarcinoma patients were included in this analysis. MRPL27 mRNA was significantly upregulated in tumor tissues in cholangiocarcinoma patients including intrahepatic, distal and hilar/perihilar cholangiocarcinoma cases (all p < 0.01). Cholangiocarcinoma patients with high MRPL27 had worse overall survival (OS) and disease-free survival (DFS) compared to those with low MRPL27 (all p < 0.05). Univariate and multivariate Cox models indicated that MRPL27 should be a risk factor for the OS and DFS in cholangiocarcinoma patients (both p < 0.01). Bioinformatic analysis revealed that MRPL27 mainly involved in the processes of mitochondrial translation elongation, respiratory electron transport, ATP synthesis, and inner mitochondrial membrane organization. No mutations of MRPL27 were screened in cholangiocarcinoma patients. Conclusion: Upregulated in tumors, MRPL27 contributes to unfavorable survival in cholangiocarcinoma patients.

Synthesis, telomerase inhibitory and anticancer activity of new 2-phenyl-4H-chromone derivatives containing 1,3,4-oxadiazole moiety

Based on previous studies, 66 2-phenyl-4H-chromone derivatives containing amide and 1,3,4-oxadiazole moieties were prepared as potential telomerase inhibitors. The results showed most of the title compounds exhibited significantly inhibitory activity on telomerase. Among them, some compounds demonstrated the most potent telomerase inhibitory activity (IC₅₀ < 1 µM), which was significantly superior to the staurosporine (IC₅₀ = 6.41 µM). In addition, clear structure–activity relationships were summarised, indicating that the substitution of the methoxy group and the position, type and number of the substituents on the phenyl ring had significant effects on telomerase activity. Among them, compound A33 showed considerable inhibition against telomerase. Flow cytometric analysis showed that compound A33 could arrest MGC-803 cell cycle at G2/M phase and induce apoptosis in a concentration-dependent way. Meanwhile, Western blotting revealed that this compound could reduce the expression of dyskerin, which is a fragment of telomerase.

Discovery of new chromen-4-one derivatives as telomerase inhibitors through regulating expression of dyskerin

A series of new trimethoxyphenyl-4H-chromen derivatives as telomerase inhibitors through regulation dyskerin were designed and synthesised. The anticancer activity assay in vitro showed that compound 5i 3-(4-(4-isonicotinoylpiperazin-1-yl)butoxy)-5,7-dimethoxy-2-(3,4,5-trimethoxyphenyl)-4H-chromen-4-one exhibited high activity against Hela, SMMC-7721, SGC-7901, U87 and HepG2 cell lines. Compound 5i also showed potent inhibitory activity against telomerase. The further results confirmed this title compound could significantly improve pathological changes induced rat hepatic tumor in vivo. Preliminary mechanisms showed that compound 5i inhibited telomerase activity through decrease expression of dyskerin.

Dyskerin and TERC expression may condition survival in lung cancer patients

Dyskerin mediates both the modification of uridine on ribosomal and small nuclear RNAs and the stabilization of the telomerase RNA component (TERC). In human tumors dyskerin expression was found to be associated with both rRNA modification and TERC levels. Moreover, dyskerin overexpression has been linked to unfavorable prognosis in a variety of tumor types, however an explanation for the latter association is not available. To clarify this point, we analyzed the connection between dyskerin expression, TERC levels and clinical outcome in two series of primary lung cancers, differing for the presence of TERC gene amplification, a genetic alteration inducing strong TERC overexpression. TERC levels were significantly higher in tumors bearing TERC gene amplification (P = 0.017). In addition, the well-established association between dyskerin expression and TERC levels was observed only in the series without TERC gene amplification (P = 0.003), while it was not present in TERC amplified tumors (P = 0.929). Similarly, the association between dyskerin expression and survival was found in cases not bearing TERC gene amplification (P = 0.009) and was not observed in TERC amplified tumors (P = 0.584). These results indicate that the influence of dyskerin expression on tumor clinical outcome is linked to its role on the maintenance of high levels of TERC.