High expression of p300 is linked to aggressive features and poor prognosis of nasopharyngeal carcinoma.
BACKGROUND
Increased expression of transcriptional coactivator p300 has been observed in a variety of human cancers. However, the expression status of p300 protein/mRNA in nasopharyngeal carcinoma (NPC) tissues and its clinicopathologic/prognostic implication are poorly understood.


METHODS
In our study, mRNA and protein expression levels of p300 was explored by reverse transcription-polymerase chain reaction (RT-PCR), Western blotting (WB) and immunohistochemistry (IHC) in nasopharyngeal mucosal and NPC tissues. The data were analyzed by receiver operating characteristic (ROC) curve analysis, spearman's rank correlation, Kaplan-Meier plots and Cox proportional hazards regression model.


RESULTS
Up-regulated expression of p300 mRNA/p300 protein was detected in NPC tissues by RT-PCR and WB, when compared to nasopharyngeal mucosal tissues. Based on ROC curve analysis, the cutoff score for p300 high expression was defined when more than 35% of the tumor cells were positively stained. High expression of p300 was observed in 127/209 (60.7%) of NPCs. In NPCs, high expression of p300 was positively associated with later T classification, later N classification, distant metastasis and later clinical stage (P < 0.05). In univariate survival analysis, overexpression of p300 was found to be an indicator of progression-free (P = 0.002) and overall survival (P = 0.001) in NPCs. More importantly, p300 expression was evaluated as an independent prognostic factor for NPC in multivariate analysis (P = 0.036).


CONCLUSIONS
Our findings support that high expression of p300 protein might be important in conferring a more aggressive behavior, and is an independent molecular marker for shortened survival time of patients with NPC.
Department of Radiation Oncology, Affiliated Tumor Hospital of Guangzhou Medical College, No.78 Hengzhigang Road Yuexiu District, Guangzhou 510095, China.
Zhi-Wei
ZW
Liao
Tong-Chong
TC
Zhou
Xiao-Jun
XJ
Tan
Xian-Lu
XL
Song
Yuan
Y
Liu
Xing-Yuan
XY
Shi
Wen-Jin
WJ
Huang
Li-Li
LL
Du
Bo-Jun
BJ
Tu
Xiao-Dan
XD
Lin
D015153:Blotting, Western; D002277:Carcinoma; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D012372:ROC Curve; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis; D050880:p300-CBP Transcription Factors / Q000378:metabolism*; D000099224:p300-CBP-Associated Factor
D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor