Related Experiment Video
Updated: Aug 25, 2026

Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
[The effects of p16 and Rb protein expression and NF-kappaB activity on hepatocarcinogenesis]
Zhao-wen Wang1, Zhi-hai Peng, Hua-mei Tang
1Department of General Surgery, Shanghai First People's Hospital, Shanghai Jiaotong University, Shanghai 200080, China.
Objective:
To study the relation between the expression of p16 protein and Rb (retinoblastoma) protein and the transcription activity of nuclear factor-kappaB (NF-kappaB) and their roles in hepatocarcinogenesis.
Methods:
p16 protein and Rb protein in 35 hepatocellular carcinoma (HCC) tissues and the peritumoral areas (more than 3 cm away from the tumor) were examined by Western blot analysis. The transcription activity of NF-kappaB in these tissues was detected by electrophoretic mobility shift assays (EMSA) and super-shift assays.
Results:
The expression rates of p16 protein in the HCC tissues and peritumoral areas were 37% (13/35) and 48% (17/35) respectively (P < 0.01). The expression rates of Rb protein in the HCC tissues and peritumoral areas were 34% (12/35) and 74% (26/35) respectively (P < 0.01). The emergence rates of NF-kappaB with transcription activity in the HCC tissues and peritumoral areas were 77% (27/35) and 85% (30/35) respectively (P > 0.05). Four out of the 10 (40%) HCC tissues expressing p16 protein and Rb protein simultaneously turned up NF-kappaB with transcription activity, while 18 out of the 20 (90%) HCC tissues not expressing both p16 and Rb proteins turned up NF-kappaB with transcription activity (P < 0.05). 13 out of the 17 (76%) peritumoral areas expressing two kinds of proteins simultaneously turned up NF-kappaB with transcription activity and the emergence rate of NF-kappaB with transcription activity in the peritumoral areas not expressing the two kinds of proteins was 89% (8/9) (P > 0.05).
Conclusion:
Dysfunction of p16 is the early event of hepatocarcinogenesis and dysfunction of Rb is the later event in this course. There is a positive correlation between p16 protein and Rb protein in HCC tissues. The loss of expression of p16 and Rb proteins plays important roles in the carcinogenesis and progression of HCC by affecting NF-kappaB transcription activity which may prevent hepocyctes from apoptosis, besides disturbing cell cycle.
Related Concept Videos
The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
Negative Regulator Molecules
Abnormal Proliferation
The Ras Gene
Ras is a superfamily...
Mutagenicity and Carcinogenicity
NF-κB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...