Levels of NOR-1 messenger RNA and transcription of its target gene CCND1 and of the NOR-1 subfamily member NUR-77 also increased in human HCC samples compared with paired HCC-free tissue.
Increased expression of cullin7 (CUL7), a gene located at the 6p21.1 locus, was demonstrated in HCC with the 6p21.1 amplicon, in parallel with a decrease in cyclin D1 expression.
Flow cytometry assay then determined that TCF over-expression helps HCC cell G1/S phase transition, and further research showed that TCF19 up-regulation inhibits p57Kip2, p21Cip1 and p27Kip1 cell cycle suppressors, enhances the expression of cyclin D1 expression and simulates retinoblastoma (Rb), FOXO1 and AKT phosphorylation.
Overexpression of cyclin D1 protein, through gene amplification, correlates with poor prognosis in several cancers, but its role in HCC is the subject of controversy.
Taken together, cells treated with oxaliplatin+ ginsenoside enhanced the anti-tumor effect and may inhibit the proliferation and promoted apoptosis of hepatocellular carcinoma via regulating the expression of PCNA and cyclin D1.
Our findings suggest that heritable CCND1 status may influence the risk of developing leukemia and HCC, and that more attention should be given to carriers of these susceptibility genes.
Furthermore, we demonstrated that miR-105 could deactivated the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway by downregulating insulin receptor substrate-1, 3-phosphoinositide-dependent protein kinase-1 and AKT1 directly, resulting in increasing cyclin-dependent kinase inhibitors 1A and 1B (p21(Cip1) and p27(Kip1)) and decreasing cyclin D1 expression in HCC.
On the other hand, genetic alterations of the cyclin D1 and p16INK4A genes were not so frequent, but appeared to be associated with the aggressive behavior of the tumor, which suggests that disruption of the cell cycle-related genes results in the progression of HCC.
Our previous study showed that CDK4/Cyclin D1 phosphorylates p53-RS at the cancer-derived Ser249 and promotes its interaction with c-Myc in the nucleus, consequently enhancing c-Myc-dependent ribosomal biogenesis and HCC cell proliferation.
Here, we show that 40% of elf(+/-) mice spontaneously develop hepatocellular cancer (HCC) with markedly increased cyclin D1, cyclin-dependent kinase 4 (Cdk4), c-Myc and MDM2 expression.
Ectopic BTG2 overexpression decreased HCC growth, caused cell cycle arrest at the G1 phase, and downregulated Cyclin D1 and Cyclin E1 protein expression.
Importantly, we delineate a new mechanism by which c-Fos could contribute to hepatocarcinogenesis through stabilization of Cyclin D1 within the nucleus, evoking a new feature to c-Fos implication in hepatocellular carcinoma.
Although it is widely assumed that CCND1 is the main driving oncogene of this common amplicon (15% frequency in HCC), both forward-transformation assays and RNAi-mediated inhibition in human HCC cells established that FGF19 is an equally important driver gene in HCC.
Among the various types of cell-cycle regulators, p16 and p27 are frequently inactivated in HCC and are considered to be potent tumor suppressors. p16, a G1-specific cell-cycle inhibitor that prevents the association of cyclindependent kinase (CDK) 4 and CDK6 with cyclin D1, is frequently inactivated in HCC via CpG methylation of its promoter region. p16 may be involved in the early steps of hepatocarcinogenesis, since p16 gene methylation has been detected in subsets of pre-neoplastic liver cirrhosis patients. p27, a negative regulator of the G1-S phase transition through inhibition of the kinase activities of Cdk2/cyclin A and Cdk2/cyclin E complexes, is now considered to be an adverse prognostic factor in HCC.
To investigate the expression and clinical significance of DEK, cyclin D1, insulin-like growth factor II (IGF-II), glypican 3 (GPC3), ribosomal phosphoprotein 0 (rpP0) mRNA in hepatocellular carcinoma (HCC) and its paraneoplastic tissues.