Probes for HPV

Abstract

Purpose

High-risk human papillomavirus (HR-HPV) infections was the causal factor in the development of cervical cancer, but the significance of HPV viral load in the prediction of the response to current therapeutic approaches had not reached consensus. The present study was performed to assess the high risk HPV viral load of cervical cancer patients who underwent radiotherapy alone or in combination with chemotherapy or hyperthermotherapy or both in correlation to long-term survival.

Methods

116 cervical cancer patients were recruited and assigned into four groups of different therapeutic modalities. The prevalent high risk types of HPV 16, 18, 58 were detected by type specific in situ hybridization (ISH), and HPV mRNA was detected by RNA scope assay using RNA scope 2.0 FFPE Reagent Kit. Semi-quantification of the HR-HPV viral load was measured based on the intensity of ISH signal captured from the tumor nests in the grey scale.

Results

The HR-HPV viral load had a significant negative correlation with survival (r_s = −0.368,P = 0.001). The 15-year survival rate of low viral load group was 68.18%, moderate viral load group was 52.17%, and high viral load group was 34.69% (P = 0.001). HPV mRNA expression was strongly consistent with HPV viral load. The 15-year survival rates of different therapeutic groups were 39.29%, 58.62%, 50.00%, 55.17%, respectively (P = 0.545). Combinatorial treatment modalities improved the actual survival, which demonstrated no significant difference among 5,10 and 15 years comparison. Cox regression analysis showed that the relative risk of death was obviously higher in the HPV 18 single positive group and high HPV viral load group.

Conclusions

The semi-quantitive viral load assessment in situ is a feasible approach in clinical practice. The more the HPV viral load was, the worse the survival of patients would be. The combinational treatments were in favor of the disease-stabilization.

Human papillomavirus (HPV) infection is associated with several genetic alterations including oncogene amplification, leading to increased aggression of tumors. Recently, a relationship between HPV infection and oncogene amplification has been reported, but this finding remains controversial. This study therefore investigated relationships between HPV infection and amplification of genes in the epidermal growth factor receptor (EGFR) signaling cascade in oral squamous cell carcinoma (OSCC). Extracted DNA from 142 formalin-fixed paraffin-embedded (FFPE) OSCC tissues was performed to investigate the copy number of EGFR, KRAS, c-myc and cyclin D1 genes using real-time polymerase chain reaction (RT-PCR) and compared with calibrators. A tissue microarray of OSCC tissues was used for detection of c-Myc expression and HPV infection by immunohistochemistry and HPV E6/E7 RNA in situ hybridization, respectively. HPV infection was also investigated using PCR and RT-PCR. Of the 142 OSCC samples, 81 (57%) were HPV-infected cases. The most frequently amplified gene was c-myc (55.6%), followed by cyclin D1 (26.1%), EGFR (23.9%) and KRAS (19.7%). Amplification of c-myc was significantly associated with levels of its protein product. EGFR amplification was also significantly associated with amplification of genes in the signaling cascade: KRAS (50.0%), c-myc (34.2%) and cyclin D1 (46.0%). Interestingly, HPV infection was significantly associated with amplification of both EGFR (76.5%) and cyclin D1 (73.0%). Only cyclin D1 amplification was significantly associated with severity of OSCC histopathology. HPV infection may play an important synergistic role in amplification of genes in the EGFR signaling cascade, leading to increased aggression in oral malignancies.

Abstract

OBJECTIVES/HYPOTHESIS:

Human papillomavirus (HPV)-positive and HPV-negative oropharyngeal squamous cell carcinoma (OPSCC) are distinct disease entities. Prognostic factors specific to each entity have not been adequately explored. Goals for this study were: 1) to determine whether HPV-positive and HPV-negative OPSCCs have distinct prognostic factors, and 2) to explore the prognostic significance of sex and race in OPSCC after HPV stratification STUDY DESIGN: Retrospective case series.

METHODS:

A retrospective review of 239 incident OPSCC patients from 1995 to 2012, treated at Johns Hopkins and University of California-San Francisco was conducted. Women and nonwhite races were oversampled. All analyses were stratified by tumor HPV in situ hybridization status. The effects of sex and race on survival were considered in Kaplan-Meier and unadjusted and adjusted Cox regression models.

RESULTS:

One hundred thirty-four (56.1%) OPSCC patients were HPV positive. On univariate analysis, women had better overall survival than men among HPV-positive (hazard ratio [HR]: 0.47, 95% confidence interval [CI]: 0.20-1.07; P = .06) but not HPV-negative (HR: 0.73, 95% CI: 0.43-1.24; P = .24) OPSCCs. On multivariate analysis, women with HPV-positive OPSCCs remained at lower risk of death (adjusted hazard ratio [aHR]: 0.34, 95% CI: 0.12-0.96; P = .04). Survival did not vary significantly by race among HPV-positive patients. Among HPV-negative patients, Hispanic patients had significantly better survival in unadjusted (HR: 0.27, 95% CI: 0.08-0.91; P = .04) but not adjusted (aHR: 0.93, 95% CI: 0.11-7.36; P = .94) analysis.

CONCLUSIONS:

Women with HPV-positive OPSCC may have improved overall survival compared to men. Sex does not play a prognostic role in HPV-negative OPSCC. There are no differences in prognosis by race among HPV-positive or HPV-negative patients.