Viral RNA patterns and high viral load reliably define oropharynx carcinomas with active HPV16 involvement.

Oropharyngeal squamous cell carcinomas (OPSCC) that are associated with human papilloma virus (HPV) infection carry a more favorable prognosis than those that are HPV-negative. However, it remains unclear which biomarker(s) can reliably determine which OPSCC specimens are truly driven by HPV infection. In this study, we analyzed 199 fresh-frozen OPSCC specimens for HPV DNA, viral load, RNA expression patterns typical for cervical carcinomas (CxCaRNA(+)), and the HPV-targeted tumor suppressor protein p16(INK4a) as markers for HPV infection. In this set of specimens, there was a 49% prevalence of DNA for the cancer-associated HPV type 16 (HPV(+)). However, there was only a 16% prevalence of high viral load and only a 20% prevalence of CxCaRNA(+), a marker of HPV16 carcinogenic activity. Among the CxCaRNA(+) tumors, 78% of the specimens exhibited overexpression of p16(INK4a), which also occurred in 14% of the HPV-negative tumors. Using a multivariate survival analysis with HPV negativity as the reference group, CxCaRNA(+) as a single marker conferred the lowest risk of death [HR = 0.28, 95% confidence interval (CI), 0.13-0.61] from oropharyngeal cancer, closely followed by high viral load (HR = 0.32, 95% CI, 0.14-0.73). In contrast, a weaker inverse association was found for OPSCC that were HPV(+) and p16(INK4a) high (HR = 0.55, 95% CI, 0.29-1.08). In summary, our findings argued that viral load or RNA pattern analysis is better suited than p16(INK4a) expression to identify HPV16-driven tumors in OPSCC patient populations.

Holzinger D ，Schmitt M ，Dyckhoff G ，Benner A ，Pawlita M ，Bosch FX ... -  《-》

Molecular characterization of p16-immunopositive but HPV DNA-negative oropharyngeal carcinomas.

Recent studies have reported that p16 protein overexpression qualifies as a surrogate marker identifying an oncogenic human papillomavirus (HPV) infection in oropharyngeal squamous cell carcinoma (OPSCC). However, there is still a percentage of OPSCCs that are positive for p16 immunohistochemistry (p16 IHC) but lack HPV DNA. The objective of this study was to characterize this group at the molecular level by performing sensitive HPV DNA- and RNA-based PCR methods and genetic profiling. All patients diagnosed with an OPSCC in the period 2000-2006 in two Dutch university medical centers were included (n = 841). The presence of HPV in a tumor sample was tested by p16 IHC followed by an HPV DNA GP5+/6+ PCR. p16 IHC scored positive in 195 samples, of which 161 were HPV DNA-positive and 34 (17%) HPV DNA-negative. In the latter group, a SPF10-LiPA25 assay, an HPV16 type-specific E7 PCR and an E6 mRNA RT-PCR were performed. Next, ten of these cases were further analyzed for loss of heterozygosity (LOH) of 15 microsatellite markers at chromosome arms 3p, 9p and 17p. Of the 34 p16-positive but PCR-negative OPSCCs, two samples tested positive by SPF10 assay, HPV16 E7 PCR and HPV16 E6 mRNA RT-PCR. Three samples tested positive by SPF10 assay but negative by the HPV16-specific assays. Nine of ten cases that were tested for LOH showed a genetic pattern comparable to that of HPV-negative tumors. This study categorizes p16-positive but HPV DNA-negative OPSCCs as HPV-negative tumors based on genetic profiling. This study highlights the importance of performing HPV testing in addition to p16 IHC for proper identification of HPV-associated OPSCCs.

Rietbergen MM ，Snijders PJ ，Beekzada D ，Braakhuis BJ ，Brink A ，Heideman DA ，Hesselink AT ，Witte BI ，Bloemena E ，Baatenburg-De Jong RJ ，Leemans CR ，Brakenhoff RH ... -  《-》

Human papillomavirus in oropharyngeal squamous cell carcinoma: assessing virus presence in normal tissue and activity in cervical metastasis.

Human papillomavirus (HPV) has been established as an etiologic and prognostic factor in oropharyngeal squamous cell carcinoma (OPSCC). HPV oncogenesis involves expression of E6/E7 oncoproteins, with downstream p53 degradation and pRb inhibition. Although much research has focused on HPV's oncogenic behavior in primary OPSCC, minimal information exists about HPV in adjacent normal and metastatic tissue. Retrospective cohort study Patient-matched tumor, normal, and metastatic tissue was gathered from 42 OPSCC patients and tested with real-time quantitative polymerase chain reaction (RT-qPCR), in situ hybridization (ISH), and immunohistochemistry (IHC). RT-qPCR was performed using total RNA from fresh-frozen tissues and primers for HPV16 E6, E7, and p16 transcripts. HPV ISH was performed to detect the presence of HPV DNA and IHC to detect p16 protein. Primary tumor, adjacent normal tissue, and tumor metastasis from 17 OPSCC patients were analyzed. When comparing the presence of HPV16 DNA in tumor, metastatic, and normal tissue by ISH, perfect correlation is found at all subsites (P < .0001). However, active infections determined by HPV16 E6 and E7 expression using quantitative polymerase chain reaction or p16 detection by IHC, were present only in primary and metastatic tissue (P = .0012, E6; P = .02, E7). No such correlation was found in normal tissue when compared to primary or metastatic tissue. There is a clear pattern of active HPV expression that correlates to disease course. In HPV-positive patients, all sites including primary, metastatic, and normal tissues are DNA positive. Transcriptionally active infections were detected in primary and metastatic tissues, whereas normal tissues appear to have latent infections.

Laborde RR ，Janus JR ，Olsen SM ，Wang VW ，Garcia JJ ，Graham RP ，Moore EJ ，Olsen KD ，Kasperbauer JL ，Price DL ，Berres M ，Halling G ，Smith DI ... -  《-》

High-risk HPV DNA status and p16 (INK4a) expression as prognostic markers in patients with squamous cell cancer of oral cavity and oropharynx.

Śnietura M ，Jaworska M ，Pigłowski W ，Goraj-Zając A ，Woźniak G ，Lange D ... -  《POLISH JOURNAL OF PATHOLOGY》

Prognostic significance of cell cycle-associated proteins p16, pRB, cyclin D1 and p53 in resected oropharyngeal carcinoma.

Plath M ，Broglie MA ，Förbs D ，Stoeckli SJ ，Jochum W ... -  《Journal of Otolaryngology-Head & Neck Surgery》