<b>Conclusion:</b> These results reveal that ZNF488, as an independent prognostic indicator, promotes cell adhesion and proliferation through collagen IV/FAK/AKT/Cyclin D1 pathway in NPC.
In this study, we showed that β-catenin signaling (including β-catenin, cyclin D1, c-Myc, and MMP-7) and p-eIF4E expression were elevated in nasopharyngeal carcinoma (NPC) compared with non-cancerous nasopharyngeal epithelial tissues, and was associated with clinical characteristics of NPC patients.
Collectively, our data revealed that EWSAT1 promotes NPC cell growth in vitro through up-regulating cyclin D1 partially via 'spongeing' miR-326/330-5p clusters.
Subgroup analysis revealed that cyclin D1 overexpression correlated significantly with nodal metastasis for laryngeal cancer (OR 2.26; 95 % CI 1.61-3.16) and was a significant poor predictor for nasopharyngeal cancer (OR 4.44; 95 % CI 1.89-10.42).
β-Catenin, c-Myc, and cyclin D1 were downregulated after SFRP1 restoration, which suggested that SFRP1 suppressed growth and metastasis by inhibiting the Wnt/β-catenin signaling pathway in NPC.
Induction of LPLUNC1 overexpression inhibited NPC cell proliferation, induced NPC cell arrest, promoted NPC cell apoptosis even after IL-6 stimulation and inhibited the growth of implanted NPC tumors in vivo, which were associated with decreasing cyclin D1 and Bcl-2 expression and the Janus kinase 2 (JAK2)/Stat3 activation, but enhancing Bax and p21 expression.
The aim of the present study was to establish a radioresistant NPC cell line to study the molecular mechanisms of radioresistance by measuring the expression of cell cycle control proteins src homology 2 domain-containing phosphatase (SHP)-1/2, p16, CDK4 and cyclin D1.
In this investigation, we knocked down CDK4 expression and observed that NPC cell growth and cell cycle progression were significantly blocked by suppressing expression of CCND1, CDK6, and E2F1 as well as elevated p21 expression.
Our previous study demonstrated that the nuclear EGFR could bind to the cyclin D1 promoter directly in the presence of LMP1, and the correlation between EGFR and STAT3 in NPC remains to be further explored.
These findings support the conclusion that the cell cycle regulation may play a role in nasopharyngeal carcinoma development and that CCND1A870G polymorphism maybe a useful biomarker for nasopharyngeal carcinoma progression.
The identification of functional miR-138 in NPC and its direct link to CCND1 might provide good candidates for developing diagnostic markers and therapeutic applications for NPC.
EBV-encoded small RNA-1 (EBER-1) hybridization signals in the NPC showed significant associations with the overexpression of Rb (P=0.000), cyclin D1 (P=0.000), CDK4 (P=0.000), and the loss of expression of p16 proteins (P=0.039).
The differentially expressed cell cycle/growth control regulators in NPC showed a stronger tendency toward cell proliferation with the up-regulation of cyclin D1, cyclin D2 etc.