Linda Luo

Detection of multiple human papillomavirus genotypes in anal carcinoma.

Infection with human papillomavirus (HPV) is a major risk factor for development of anal squamous cell carcinoma. Despite over 100 genotypes of the virus, HPV 16 and 18 are considered pathogenic as they are seen in the majority of cervical and anal cancers. We have employed a custom microarray to examine DNA for several HPV genotypes. We aimed to determine the accuracy of our microarray in anal cancer DNA for HPV genotypes compared to the DNA sequencing gold standard.MethodsWe utilized a sensitive microarray platform to classify 37 types of mucosal HPVs including 14 known high-risk and 23 low-risk types based on cervical cancer data. We utilized DNA from pathologically confirmed cases of anal squamous cell carcinoma. All samples underwent microarray HPV genotyping and PCR analysis.ResultsHPV was detected in 18/20 (90%) anal cancers. HPV genotypes 16 and 18 were present in the majority of specimens, with HPV 16 being the most common. Eighty percent of anal cancers had at least two HPV types. Ten percent of cases (2/20) tested negative using our microarray; DNA sequencing confirmed the lack of presence of HPV DNA in these samples.ConclusionsMicroarray technology is an accurate way to screen for various genotypes of HPV in anal cancer, with 100% correlation with genomic DNA detection of HPV. The majority of anal cancers in our study associated with pathogenic HPV 16 and/or 18. Other HPV genotypes are present simultaneously with HPV 16 and 18, and might contribute to its pathogenesis.

John Cunningham virus T‐antigen expression in anal carcinoma

Anal carcinoma is thought to be driven by human papillomavirus (HPV) infection through interrupting function of cell regulatory proteins such as p53 and pRb. John Cunningham virus (JCV) expresses a T‐antigen that causes malignant transformation through development of aneuploidy and interaction with some of the same regulatory proteins as HPV. JCV T‐antigen is present in brain, gastric, and colon malignancies, but has not been evaluated in anal cancers. The authors examined a cohort of anal cancers for JCV T‐antigen and correlated this with clinicopathologic data.

Tobacco smoking and risk of recurrence for squamous cell cancer of the anus

OBJECTIVE Squamous cell cancer of the anus is associated with multiple risk factors, including infection with human papillomavirus, immunosuppression, chronic inflammation, and tobacco smoking, although there is little data on these factors for the prediction of recurrent disease. Here, we evaluated the risk of recurrence and mortality of anal carcinoma in association with tobacco smoking. METHODS We conducted a retrospective review of cases of anal carcinoma from two local hospitals. We obtained information on treatment response and cancer recurrence, as well as tobacco usage from medical records. RESULTS We identified 64 patients with squamous cell cancer of the anus, and 34 of these (53%) had a tobacco smoking history. Current smokers had higher carcinoma recurrence rates (11/34, 32%) than non-smokers (6/30, 20%). Overall mortality was 33% (21/64), and cancer-related mortality was 23% (15/64). Smokers were more likely to die from recurrence than non-smokers, with 45% of smokers dead compared to only 20% of non-smokers by 5 years after treatment. CONCLUSION Tobacco smoking appears to be associated with anal carcinoma disease recurrence, and is related to increased mortality. This data suggests that patients should be cautioned about tobacco smoking once a diagnosis of anal carcinoma is made in attempt to improve their long-term outcome.

Tumor-infiltrating CD8+ T lymphocytes associated with clinical outcome in anal squamous cell carcinoma

The prognostic significance of tumor‐infiltrating CD8+ T lymphocytes in anal squamous cell carcinoma (SCC) remains unclear. We designed the study to investigate the association between CD8+ T cells and clinical prognosis among anal SCC patients.

Loss of histone variant macroH2A2 expression associates with progression of anal neoplasm

Aims The macroH2A histone variants are epigenetic marks for inactivated chromatin. In this study, we examined the expression of macroH2A2 in anal neoplasm from anal intraepithelial neoplasia (AIN) to anal squamous cell carcinoma (SCC). Methods AIN and anal SCC samples were analysed for macroH2A2 expression, HIV and human papilloma virus (HPV). The association of macroH2A2 expression with clinical grade, disease recurrence, overall survival and viral involvement was determined. Results macroH2A2 was expressed in normal squamous tissue and lower grade AIN (I and II). Expression was lost in 38% of high-grade AIN (III) and 71% of anal SCC (p=0.002). Patients with AIN with macroH2A2-negative lesions showed earlier recurrence than those with macroH2A2-positive neoplasm (p=0.017). With anal SCC, macroH2A2 loss was more prevalent in the HPV-negative tumours. Conclusions Loss of histone variant macroH2A2 expression is associated with the progression of anal neoplasm and can be used as a prognostic biomarker for high-grade AIN and SCC.

Development of Human-Derived Cell Culture Lines for Recurrent Respiratory Papillomatosis

Recurrent respiratory papillomatosis (RRP) is mainly caused by human papillomavirus (HPV) 6 and 11. While various adjuvant therapies have been reported, no effective therapy has been documented to universally “cure” this disease. In the era of precision medicine, it would be valuable to identify effective intervention based on drug sensitivity testing and/or molecular analysis. It is essential to be able to successfully carry out in vitro culture and expand tumor cells directly from patients to accomplish this goal. Here we report the result of successful culture of HPV-infected cell lines (success rate 70%, 9/13) that express the E6/E7 RNA transcript, using pathologic tissue biopsies from patients treated at our institution. The availability of such a system would enable ex vivo therapeutic testing and disease modeling.

T1906 CD8+ T Cell Infiltration and Cancer Recrurrence in Squamous Cell Cancer of the Anus

Background. The prognosis of patients with squamous cell cancer of the anus is most dependent on tumor staging and histopathology. Recent evidence suggests that the adaptive immune response, represented by T cells, is important in predicting clinical outcome in colon and other cancers. CD8+ T cells are a subpopulation of cytotoxic immune cells that have the potential to respond to and kill cancer cells. In this study, we correlated CD8+ T cell tumor infiltration with histopathology, HIV and HPV status, and anal cancer recurrence. Methods. Archived, formalin-fixed tissues from 16 cases of squamous cell cancer of the anus were analyzed for CD8+ T cell infiltration using an anti-CD8 antibody. High-power microscope images were taken of the tumor with CD8+ cells counted by two observers. Tumors were called high infiltration if >150CD8+ cells/HPF, low infiltration if 10 and <150 CD8+ cells/HPF. Each case was reviewed for histopathologic grade of tumor (well, moderate or poorly differentiated). This data was then correlated with retrospective clinical data on HIV status, and cancer recurrence after IRB approval was obtained. Results. Of the sixteen cases of anal cancer included in the study, the histopathology showed: well-differentiated 4/16 (25%), moderately-differentiated 7/16 (44%) and poorly-differentiated 5/16 (31%). HIV was documented in 7/16 (44%) of cases. The overall recurrence rate in this population was 6/16 (37%). High CD8+ T cell infiltration was seen in 6/16 (37%) of cases, medium 4/16 (31%), and low infiltration in 6/16 (38%) of cases. There was a significant correlation between high CD8+ T cell infiltration and well to moderately differentiated tumors and between low CD8+ T cell infiltration and poorly differentiated tumors (p<0.05). Of the patients with cancer recurrence two-thirds had low CD8+ T cell infiltration (p<0.05). Of the seven patients in our cohort that were HIV positive, 70% of these patients had low CD8+ T cell infiltration (p<0.05). Conclusions. There is a strong correlation of infiltrating CD8+ T cells with anal cancer tumors and histopathologic diagnosis, HIV status and cancer recurrence. The CD8+ T cell infiltration may confer part of the improved survival observed in HIV negative patients and in those patients with tumors that are well to moderately differentiated.