SS 05-04Active human papillomavirus involvement in Barrett’s dysplasia and oesophageal adenocarcinoma is characterized by wild-type p53 and aberrations of the retinoblastoma protein pathway

27. HPV and oropharynx / Head and neck cancer
S. Rajendra 1, T. Yang 2, W. Xuan 3, P. Sharma 4, D. Pavey 5, C.S. Lee 5, S. Le 5, J. Collins 5, B. Wang 5.
1Department of Gastroenterology, Bankstown-Lidcombe Hospital & University of New South Wales, Sydney, (Australia), 2South Western Sydney Area Pathology Service (Australia), 3Ingham Institute for Applied Medical Research, Liverpool, Sydney (Australia), 4University of Kansas City, Missouri (United States), 5Department of Gastroenterology, Bankstown-Lidcombe Hospital, Sydney (Australia)

Background / Objectives

We have previously demonstrated that transcriptionally active high-risk HPV (hr-HPV) is strongly incriminated in Barrett’s dysplasia (BD) and oesophageal adenocarcinoma (OAC) using mainly fresh frozen tissue.1-4 This study aimed to identify biomarkers of active HPV infection in Barrett’s metaplasia, (BM)/BD/OAC by immunohistochemical staining (IHC) of formalin-fixed paraffin embedded (FFPE) tissue for aberrations of p53 and the retinoblastoma (pRb) pathway which are targets for the viral oncoproteins, E6/E7 respectively. 


Methods

Prospectively, BM(n=81)/BD(n=72)/OAC(n=65) FFPE specimens were subjected to IHC staining for pRb, p16INK4A, cyclin D1, p53 and RNA in-situ hybridization (ISH) for E6/E7 transcripts. HPV DNA was determined via PCR in fresh frozen specimens. Viral load measurement (real-time PCR) and Next Generation Sequencing of TP53 was also performed.


Results

Of 218 patients, 56 were HPV DNA positive [HPV16 (n=42), 18 (n=13), 6 (n=1)]. Viral load was low. Transcriptionally active HPV (DNA+/RNA+) was only found in the dysplastic and adenocarcinoma group (n=21). The majority of HPV DNA+/RNA+ BD/OAC were characterized by p16INK4Ahigh (14/21, 66.7%), pRblow (15/21, 71.4%) and p53low (20/21, 95%) and was significantly different to controls [combination of HPV DNA-/RNA- (n=94) and HPV DNA+/RNA- cohorts (n=22)] p53low had the strongest association with DNA+/RNA+ oesophageal lesions (OR=23.5, 95% CI=2.94-187.8, p=0.0029). Seventeen HPV DNA+/RNA+ BD/OAC identified as p53low, were sequenced and all but one exhibited wild-type status. pRblow/p53low provided the best balance of strength of association (OR=8.0, 95% CI=2.6-25.0, p=0.0003) and sensitivity (71.4%)/specificity (71.6%) for DNA+/RNA+ BD/OAC. 


Conclusion

Active HPV involvement in BD/OAC is characterized by wild-type p53 and aberrations of the retinoblastoma protein pathway.


References

 

            1. Rajendra S, Wang B, Snow ET, Sharma P, Pavey D, Merrett N, Ball MJ, Brain T, Fernando R, Robertson IK. Transcriptionally active human papillomavirus is strongly associated with Barrett's dysplasia and esophageal adenocarcinoma. Am J Gastroenterol 2013;108: 1082-93.

            2. Wang B, Rajendra S, Pavey D, Sharma P, Merrett N, Wu X, Snow ET, Kumbhari V, Ball MJ, Robertson IK. Viral load and integration status of high-risk human papillomaviruses in the Barrett's metaplasia-dysplasia-adenocarcinoma sequence. Am J Gastroenterol 2013;108: 1814-6.

            3. Rajendra S, Wang B, Pavey D, Sharma P, Yang T, Lee CS, Gupta N, Ball MJ, Gill RS, Wu X. Persistence of Human Papillomavirus, Overexpression of p53, and Outcomes of Patients After Endoscopic Ablation of Barrett's Esophagus. Clin Gastroenterol Hepatol 2015;13: 1364-1368.

            4. Rajendra S, Wang B, Merrett N, Sharma P, Humphris J, Lee HC, Wu J. Genomic analysis of HPV-positive versus HPV-negative oesophageal adenocarcinoma identifies a differential mutational landscape. J Med Genet 2016;53: 227-31.