SP1-induced lncRNA DUBR promotes stemness and oxaliplatin resistance of hepatocellular carcinoma via E2F1-CIP2A feedback.

Oxaliplatin-based chemotherapy is widely used to treat advanced hepatocellular carcinoma (HCC), but many patients develop drug resistance that leads to tumor recurrence. Cancer stem cells (CSCs) are known to contribute to chemoresistance, the underlying mechanism, however, remains largely unknown. In this study, we discovered a specificity protein 1 (SP1)-induced long noncoding RNA--DPPA2 upstream binding RNA (DUBR) and its high expression in HCC tissues and liver CSCs. DUBR was associated with HCC progression and poor chemotherapy response. Moreover, DUBR facilitated the stemness and oxaliplatin resistance of HCC in vitro and in vivo. Mechanistically, DUBR upregulated cancerous inhibitor of protein phosphatase 2A (CIP2A) expression through E2F1-mediated transcription regulation. DUBR also exerted function by binding microRNA (miR)-520d-5p as a competing endogenous RNA to upregulate CIP2A at mRNA level. CIP2A, in turn, stabilized E2F1 protein and activated the Notch1 signaling pathway, thereby increasing the stemness feature of HCC and leading to chemoresistance. In conclusion, we identified SP1/DUBR/E2F1-CIP2A as a critical axis to activate the Notch1 signaling pathway and promote stemness and chemoresistance of HCC. Therefore, DUBR could be a potential target in HCC treatment.

Effects of lncRNA gm4419 on rats with hypertensive cerebral atherosclerosis through NF-κB pathway.

OBJECTIVE: To explore the effects of long non-coding ribonucleic acid (lncRNA) Gm4419 on rats with hypertensive cerebral atherosclerosis through the nuclear factor-kappa B (NF-κB) pathway. MATERIALS AND METHODS: Healthy male rats were selected and randomly divided into control group, model group (hypertensive cerebral atherosclerosis model), and lncRNA group (hypertensive cerebral atherosclerosis model + lncRNA injection). Neurological deficit scoring criteria, flow cytometry, Western blotting, and staining method were adopted to measure the differences in the neurological function score, NF-κB activity, and chemerin level of rats in the three groups. RESULTS: The neurological scores revealed that the neurological function of rats was not damaged in control group, while it was severely damaged in model group. However, the neurological function of rats was more severely damaged in lncRNA group than that in control group and model group, while the neurological function deficits were slighter in model group. In terms of NF-κB expression activity in mononuclear cells, the serum activity of NF-κB in control group appeared the lowest among the three groups and was significantly higher in lncRNA group than in model group. The serum chemerin level was evidently increased in model group compared with control group, while it was significantly decreased in lncRNA group compared with model group and control group. Moreover, the levels of NF-κB and chemerin were most evidently influenced in lncRNA group. CONCLUSIONS: Activating the NF-κB signal, lncRNA Gm4419 promotes the expression of chemerin signal, accelerates the apoptosis of nerve cells, and motivates the deterioration of hypertensive cerebral arteriosclerosis.

Genetic polymorphisms in MDR1 and CYP3A5 and MDR1 haplotype in mainland Chinese Han, Uygur and Kazakh ethnic groups.

BACKGROUND AND OBJECTIVE: The drug transporter MDR1 and the drug metabolizing enzyme CYP3A are the two major biological factors determining the pharmacokinetics of many drugs. The functional MDR1 single nucleotide polymorphisms (SNPs) and a prevalent CYP3A5 SNP show marked interethnic variation among Orientals, Caucasians and Africans. In this study, we investigated the distribution of MDR1 and CYP3A5 SNPs among mainland Chinese Han, Uygur and Kazakh ethnic groups. METHODS: Genotypes of the MDR1 C1236T, G2677T/A and C3435T, and CYP3A5*3, CYP3AP1*3 SNPs were determined in 434 unrelated healthy subjects (165 Chinese Han, 161 Chinese Uygur and 108 Chinese Kazakh) using polymerase chain reaction followed by restriction fragment length polymorphism analysis. RESULTS AND DISCUSSION: A significantly higher MDR1 3435T variant frequency was observed in Uygur (52.8%), than in Kazakh (39.8%) and Han (37.9%) Chinese (P < 0.01, Fisher's exact test). There was no significant difference in MDR1 1236T and 2677T/A variant frequencies between Han, Uygur and Kazakh. CYP3A5*3 (G) allele was observed at intermediate frequencies in Uygur (84.8%) and Kazakh (86.6%), relative to Han (72.7%) and values previously reported in Caucasians (91.7%). The CYP3AP1*3 (A) allele was strongly linked to CYP3A5*3 in Chinese Han, Uygur and Kazakh. CONCLUSION: Significant interethnic differences in MDR1 haplotype and CYP3A5 variant frequencies exist between mainland Chinese Han and Caucasians, and the intermediate frequencies observed in Chinese Uygur and Kazakh might be due to the genetic admixture of Eurasians and Orientals.