Effects of irradiation on human leukocyte antigen class I expression in human papillomavirus positive and negative base of tongue and mobile tongue squamous cell carcinoma cell lines.

Human papillomavirus (HPV) infection is a risk factor for oropharyngeal cancer, besides smoking and alcohol. Patients with HPV-positive tumors have a better prognosis than those with HPV-negative tumors. Furthermore, patients with HPV-positive tumors, with high CD8+ tumor infiltrating lymphocyte counts or absent/low human leukocyte antigen (HLA) class I expression have the best outcome. The latter is paradoxical, since HLA class I expression is important for tumor recognition. Below, the hypothesis that radiation therapy increases HLA class I expression was tested. HPV16 positive head and neck cancer cell lines UPCI-SCC-154, UPCI-SCC-090 and UM-SCC-47, and the HPV-negative cancer cell line UT-SCC-14, were treated with 2-10 Gray (Gy) and tested for HLA class I expression, cell cycle changes and apoptosis by flow cytometry. HPV16 E5, E7 and HLA-A mRNA expression was tested by quantitative PCR. A dose of 10 Gy resulted in a tendency of increased HLA class I cell surface expression for all cell lines and reached statistical significance for UPCI-SCC-154 and UPCI-SCC-090. There were, however, no significant changes in HLA-A mRNA expression in any of the cell lines, or HPV16 E5, or E7 mRNA expression for UPCI-SCC-47 and UPCI-SCC-154, while for UPCI-SCC-090 HPV16 E5 mRNA decreased. In all cell lines there was a shift towards G2/M phase and increased apoptosis after irradiation with 10 Gy. To conclude, irradiation with 10 Gy increased HLA class I expression in the HPV-positive cell lines UPCI-SCC-154 and UPCI-SCC-090. A similar tendency was observed for HPV-positive UM-SCC-47 and HPV-negative UT-SCC-14.

Human papillomavirus DNA detection in fine-needle aspirates as indicator of human papillomavirus-positive oropharyngeal squamous cell carcinoma: A prospective study.

BACKGROUND: Human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (SCC) has a better outcome than most head neck squamous cell carcinomas (HNSCCs) and an HPV-positive lymph node metastasis likely has an HPV-positive oropharyngeal SCC origin. Determining HPV-status in cervical lymph nodes by fine-needle aspiration cytology (FNAC) may be useful for diagnosis. METHODS: FNACs from 66 patients with neck masses were prospectively examined for HPV DNA and HPV16 mRNA by a polymerase chain reaction (PCR)-based assay, and the data correlated to diagnosis and HPV-status obtained from histopathological specimens. RESULTS: Aspirates from 17 of 66 patients, later diagnosed with HPV-positive oropharyngeal SCC, were HPV16 DNA-positive. HPV16 mRNA was detected in all cases with extractable RNA. All remaining FNACs, including 18 branchial cleft cysts, were HPV DNA-negative. HPV DNA status in the aspirates showed perfect concordance with corresponding biopsies. CONCLUSION: HPV16 DNA detection in fine-needle aspirations from neck masses is reliable and HPV16 DNA in a metastasis is a strong indicator of an HPV-positive oropharyngeal SCC. © 2016 Wiley Periodicals, Inc. Head Neck 39: 419-426, 2017.

Human papillomavirus DNA and p16(INK4a) expression in hypopharyngeal cancer and in relation to clinical outcome, in Stockholm, Sweden.

OBJECTIVES: Hypopharyngeal cancer is a subset of head neck squamous cell carcinoma (HNSCC) with particularly poor prognosis. Human papillomavirus (HPV) is a risk factor for some HNSCC, and its presence is of prognostic value for certain subsites. However, its influence on survival in hypopharyngeal cancer has not been thoroughly investigated. Here we examine HPV DNA and p16(INK4a) (p16) overexpression in relation to clinical outcome. MATERIALS AND METHODS: Hypopharyngeal tumour biopsies from 82 patients diagnosed 2008-2013 were examined for presence of HPV DNA by a bead-based multiplex assay and for p16 expression by immunohistochemistry, and the obtained data compared to that acquired previously from 109 patients diagnosed 2000-2007 at the same clinic. A survival analysis was then performed on 142 patients (from both studies) treated with curative intent and a 3-year follow-up time. RESULTS: Of the tumour biopsies 3/82 (3.7%) were HPV16 DNA and p16 positive, while 12/82 (14.6%) were p16 positive, equivalent to that in the previous study. Overall 3-year survival was significantly more favourable for patients with HPV16 DNA and p16 positive tumours as compared to survival of the other patients (86% vs. 31%, p=0.0185). A similar but not statistically significant trend was found for disease specific survival. CONCLUSION: HPV DNA and p16 positive hypopharyngeal cancer was rare and had not increased, but had a better clinical outcome as compared to other HPV-unrelated hypopharyngeal cancer. In addition, p16 overexpression was not a suitable surrogate marker for presence of HPV or for prediction of survival in this type of cancer.

A model for predicting clinical outcome in patients with human papillomavirus-positive tonsillar and base of tongue cancer.

AIM: To combine clinical and molecular markers into an algorithm for predicting outcome for individual patients with human papillomavirus (HPV) DNA/p16(INK4a) positive tonsillar and base of tongue squamous cell carcinoma (TSCC and BOTSCC). BACKGROUND: Head-neck cancer treatment has become more intensified, comprising not only surgery and radiotherapy, but also induction/concomitant chemotherapy and targeted therapy. With less treatment, 3-year disease free survival (DFS) is 80% for HPV-positive TSCC and BOTSCC. An 85-100% 3-year DFS is observed for HPV(+) TSCC and BOTSCC with absence of HLA class I, or CD44 expression, or high CD8(+) tumour-infiltrating lymphocyte (TIL) counts suggesting that therapy could be tapered for many if patients could be identified individually. PATIENTS AND METHODS: Patients treated curatively, with HPV DNA/p16(INK4a) positive tumours examined for HLA class I and II, CD44 and CD8(+)TILs, were included. An L1-regularised logistic regression was used to evaluate the effect of the biomarker data, age, stage, diagnosis, smoking and treatment on 3-year risk of death or relapse on a training cohort of 197 patients diagnosed 2000-2007 and validated on a cohort of 118 patients diagnosed 2008-2011. RESULTS: The variables finally included in the model were HLA class I, CD8(+) TILs, age, stage and diagnosis (TSCC or BOTSCC). The model showed acceptable discrimination and calibration. The discriminative ability of the model did not diminish after validation (AUC=0.77). CONCLUSION: To our knowledge, this is the first model to utilise information from several markers to predict an individual probability of clinical outcome for patients with HPV DNA/p16(INK4a) positive tumours.

Reduced Expression of the Antigen Processing Machinery Components TAP2, LMP2, and LMP7 in Tonsillar and Base of Tongue Cancer and Implications for Clinical Outcome.

OBJECTIVES: Patients with human papillomavirus (HPV)-positive tonsillar squamous cell carcinoma (TSCC) and base of tongue squamous cell carcinoma (BOTSCC) have a better clinical outcome than those with corresponding HPV-negative tumors. Moreover, there is a strong positive correlation between absent/low as opposed to strong HLA class I expression and favorable clinical outcome for HPV-positive tumors, while the reverse applies to HPV-negative tumors. The expression of the antigen processing machinery (APM) components TAP1, TAP2, LMP2, and LMP7 in these tumors in relation to HPV status, HLA class I expression, each other, and clinical outcome was therefore investigated. MATERIAL AND METHODS: Formalin-fixed paraffin-embedded TSCC and BOTSCC, derived from 151 patients and previously analyzed for HPV DNA, HLA class I, and LMP10 expression were stained by immunohistochemistry for TAP1, TAP2, LMP2, and LMP7. RESULTS: Absent/low TAP2, LMP2, and LMP7 expression, similar to HLA class I and LMP10, was common in TSCC and BOTSCC, irrespective of HPV status. Expression of TAP1 and TAP2 was correlated, as was LMP2 to LMP7. LMP2 and LMP7 expression was also associated to HLA class I expression. Moreover, absence of LMP7 was linked to increased disease-free survival in both HPV-positive and HPV-negative cases. CONCLUSION: Reduced expression of TAP2, LMP2, and LMP7 was frequent in TSCC and BOTSCC and their expression as well as that of TAP1 was often interrelated. Furthermore, low LMP7 expression correlated to better clinical outcome and may, together with HPV status, potentially be used for prediction of treatment response.

Incidence of human papillomavirus positive tonsillar and base of tongue carcinoma: a stabilisation of an epidemic of viral induced carcinoma?

AIM: To investigate whether the rise during the past decades in the incidence of tonsillar and base of tongue squamous cell carcinoma (TSCC and BOTSCC) and the proportion of human papillomavirus (HPV) positive cancer has continued in Stockholm. PATIENTS AND METHODS: Pre-treatment biopsies (n=252) available from 280 patients diagnosed with TSCC and BOTSCC during 2008-2012 in the County of Stockholm were tested for HPV DNA by a multiplex bead-based assay. Incidence records were acquired from the Swedish Cancer Registry. The data obtained were evaluated together with previous figures from 1970 to 2007. RESULTS: HPV DNA was present in 186/252 (74%) of TSCC and BOTSCC biopsies obtained during 2008-2012 in Stockholm. In this region the age-standardised incidence, including the prevalence of HPV-positive and HPV-negative TSCC stabilised 2007-2012 compared to 2000-2006, while for BOTSCC throughout 1998-2012 the same parameters increased moderately (p<0.05, for all). In parallel, from 2000 to 2006 through 2007-2012 in Sweden, the age-standardised incidence of both TSCC and BOTSCC continued to rise (p=0.012 and p=0.001 respectively). CONCLUSION: During 2000-2012 the age-standardised incidence and the proportion of HPV-positive TSCC have stabilised at a high level, while the proportion of HPV-negative cancer has remained at a low level in Stockholm, whereas for BOTSCC all parameters are increasing moderately. In contrast, in Sweden the incidence of both TSCC and BOTSCC is still increasing. We hypothesise that the HPV epidemic could be stabilising, first for TSCC, but so far not for BOTSCC, in e.g. some urban areas, while previous trends for both tumours persist at other geographic locations.

No association between Birt-Hogg-Dubé syndrome skin fibrofolliculomas and the first 10 described human polyomaviruses or human papillomaviruses.

The rare autosomal dominant condition Birt-Hogg-Dubé syndrome (BHD) is attributed to mutations on chromosome 17 in the folliculin (FLCN) gene, but not always diagnosed due to lack of, or a variety of symptoms such as fibrofolliculomas, lung cystic lesions, spontaneous pneumothorax and renal cancer. We hypothesized that the lack of or variability in symptoms could be due to BHD patients potentially being abnormally susceptible to infections with human papillomavirus (HPV) or human polyomavirus (HPyV), which can be associated with skin lesions or latency in the kidneys. Seven fibrofolliculoma skin lesions, one renal cancer and one lung cyst from nine patients with BHD treated at the Karolinska University Hospital were therefore analyzed for cutaneous and mucosal HPV types and 10 HPyVs by bead based multiplex assays or by PCR. All samples were negative for viral DNA. In conclusion, the data suggest that HPV and HPyVs do not contribute to BHD pathology.

Correlation of LMP10 expression and clinical outcome in Human Papillomavirus (HPV) positive and HPV-Negative tonsillar and base of tongue cancer.

AIM: To examine LMP10 expression and its possible impact on clinical outcome in human papillomavirus (HPV) positive and HPV-negative tonsillar and base of tongue squamous cell carcinoma (TSCC and BOTSCC). BACKGROUND: Outcome is better in HPV-positive TSCC and BOTSCC compared to matching HPV-negative tumours, with roughly 80% vs. 40% 5-year disease free survival (DFS) with less aggressive treatment than today's chemoradiotherapy. Since current treatment often results in harmful side effects, less intensive therapy, with sustained patient survival would be an attractive alternative. However, other markers together with HPV status are necessary to select patients and for this purpose LMP10 expression is investigated here in parallel to HPV status and clinical outcome. MATERIALS AND METHODS: From 385 patients diagnosed between 2000 and 2007 at the Karolinska University Hospital, 278 formalin fixed paraffin embedded TSCC and BOTSCC biopsies, with known HPV DNA status, were tested for LMP10 nuclear and cytoplasmic expression (fraction of positive cells and staining intensity). The data was then correlated to clinical outcome. RESULTS: An absent/low compared to a moderate/high LMP10 nuclear fraction of positive cells was correlated to a better 3-year DFS in the HPV-positive group of patients (log-rank p = 0.005), but not in the HPV-negative group. In the HPV-negative group of patients, in contrast to the HPV-positive group, moderate/high LMP10 cytoplasmic fraction and weak/moderate/high LMP10 cytoplasmic intensity correlated to a better 3-year DFS (p = 0.003 and p = 0.001) and 3-year overall survival (p = 0.001 and 0.009). CONCLUSION: LMP10 nuclear expression in the HPV-positive group and LMP10 cytoplasmic expression in the HPV-negative group of patients correlated to better clinical outcome.

HLA-A*02 in relation to outcome in human papillomavirus positive tonsillar and base of tongue cancer.

BACKGROUND/AIM: Patients with human papillomavirus (HPV)-positive tonsillar and base of tongue cancer have a better outcome than those with corresponding HPV-negative tumors (80% vs. 40% 5-year disease free survival with conventional radiotherapy). They should not all need chemoradiotherapy, but before tapering treatment, more markers are needed to predict treatment response. In the present study, human leukocyte antigen (HLA) - HLA-A*02 was analyzed with HPV as a prognostic factor for tonsillar and base of tongue cancer. PATIENTS AND METHODS: Pre-treatment biopsies, previously tested for HPV DNA, from 425 patients diagnosed with tonsillar and base of tongue cancer between 2000-2009 at the Karolinska University Hospital were examined for HLA-A*02. RESULTS: HLA-A*02 was present in 144/305 (47.2%) of the HPV-positive and 63/120 (52.8%) of the HPV-negative tumours. Among 383 patients treated with curative intent, absence of HLA-A*02 was correlated with increased disease-free survival in the HPV-positive (p=0.016), but not in the HPV-negative group. CONCLUSION: Absence of HLA-A*02 correlated with better disease-free survival for patients with HPV-positive tonsillar and base of tongue cancer.

Human papillomavirus prevalence is high in oral samples of patients with tonsillar and base of tongue cancer.

MATERIAL AND METHODS: Presence of HPV DNA was analyzed in mouthwash and tonsillar swab samples, if indicative of HPV-positive tonsillar or base of tongue cancer in 76 patients, with suspected head neck cancer, undergoing diagnostic endoscopy at Karolinska University Hospital. The diagnosis and tumor HPV status was later obtained from patients' records. As controls, 37 tumor-free dental visitors were included. RESULTS: Of the 76 patients, 22/29 (76%) and 16/18 (89%) had an HPV-positive tonsillar and base of tongue cancer respectively, with 18/22 (82%) and 8/16 (50%) respectively having tumor concordant HPV-type positive oral samples. Two other HPV-positive oral samples in the base of tongue cancer group did not correlate to the tumor HPV status. Among the remaining patients, 19 with other head neck cancer and 10 with benign conditions, 4/29 (14%) had HPV-positive oral samples. Consequently, of the HPV-positive oral samples, dominated by HPV16 and high signals, 27/32 (84%) were derived from 26 patients with concordant HPV-type positive tonsillar or base of tongue cancer and one patient with an unknown primary head and neck cancer. The other five HPV-positive oral samples, with mainly low signals were derived from two patients with non-concordant HPV-type positive tumor biopsies, two patients with HPV-negative tumor biopsies and a patient with a benign condition. Of the dental patients, 3/37 (8%) had HPV-positive tonsillar swabs with weak signals. CONCLUSION: In patients with suspected head neck cancer, HPV-positive oral samples, especially HPV16 with high signals, could be indicative of HPV-positive tonsillar or base of tongue cancer.

DNA from human polyomaviruses, TSPyV, MWPyV, HPyV6, 7 and 9 was not detected in primary mucosal melanomas.

BACKGROUND/AIM: Mucosal melanomas arise in non UV-light exposed areas and causative factors are yet unknown. Human polyomaviruses (HPyVs) are rapidly increasing in numbers and are potentially oncogenic, as has been established for MCPyV in Merkel cell carcinoma, an unusual skin cancer type. The aim of the present study was to investigate the association between TSPyV, MWPyV, HPyV6, 7 and 9 and mucosal melanoma. MATERIALS AND METHODS: Fifty-five mucosal melanomas, were analyzed by a Luminex assay, for the presence of 10 HPyVs (BKPyV, JCPyV, KIPyV, WUPyV, TSPyV, MWPyV, HPyV6, 7 and 9) and two primate viruses (SV40 and LPyV). RESULTS: In 37 samples the DNA quality was satisfactory for analysis. However, none of the samples analyzed were positive for any of the examined viruses. CONCLUSION: None of the above-analyzed HPyVs were detected in mucosal melanoma samples, and they are for this reason unlikely to play a major role in the development of this tumor type.

Absent/weak CD44 intensity and positive human papillomavirus (HPV) status in oropharyngeal squamous cell carcinoma indicates a very high survival.

Patients with human papillomavirus DNA positive (HPV(DNA+)) oropharyngeal squamous cell carcinoma (OSCC) have better clinical outcome than those with HPV DNA negative (HPV(DNA-)) OSCC upon intensive oncological treatment. All HPV(DNA+) OSCC patients may not require intensive treatment, however, but before potentially deintensifying treatment, additional predictive markers are needed. Here, we examined HPV, p16(INK4a), and CD44 in OSCC in correlation to clinical outcome. Pretreatment tumors from 290 OSCC patients, the majority not receiving chemotherapy, were analyzed for HPV DNA by Luminex and for p16(INK4a) and CD44 by immunohistochemistry. 225/290 (78%) tumors were HPV(DNA+) and 211/290 (73%) overexpressed p16(INK4a), which correlated to presence of HPV (P < 0.0001). Presence of HPV DNA, absent/weak CD44 intensity staining correlated to favorable 3-year disease-free survival (DFS) and overall survival (OS) by univariate and multivariate analysis, and likewise for p16(INK4a) by univariate analysis. Upon stratification for HPV, HPV(DNA+) OSCC with absent/weak CD44 intensity presented the significantly best 3-year DFS and OS, with >95% 3-year DFS and OS. Furthermore, in HPV(DNA+) OSCC, p16(INK4a)+ overexpression correlated to a favorable 3-year OS. In conclusion, patients with HPV(DNA+) and absent/weak CD44 intensity OSCC presented the best survival and this marker combination could possibly be used for selecting patients for tailored deintensified treatment in prospective clinical trials.

Oral human papillomavirus prevalence in high school students of one municipality in Sweden.

The rise in human papillomavirus (HPV) infection has been suggested to be responsible for the increased incidence of oropharyngeal cancer in the Western world. This has boosted interest in oral HPV prevalence and whether HPV vaccines can prevent oral HPV infection. In a previous study we showed oral HPV prevalence to be almost 10% in youth aged 15-23 y attending a youth clinic in Stockholm, Sweden. However, this may not be a generalizable sample within the Swedish population. Therefore, mouthwashes were used to investigate oral HPV prevalence in 335 Swedish high school students aged 17-21 y (median age 18 y), from 1 municipality with 140,000 inhabitants. The presence of HPV DNA in the oral samples, as examined by a Luminex-based assay, was significantly lower in this cohort, only 1.8% (3.1% in females and 0.6% in males), as compared to our previous study.

CD8+ and CD4+ tumour infiltrating lymphocytes in relation to human papillomavirus status and clinical outcome in tonsillar and base of tongue squamous cell carcinoma.

Patients with human papillomavirus (HPV) positive tonsillar and base of tongue squamous cell carcinoma (TSCC and BOTSCC, respectively) have a better clinical outcome than those with HPV negative tumours, irrespective of treatment. However, to better individualise treatment, additional biomarkers are needed together with HPV status. In a pilot study, we showed that high numbers of CD8(+) tumour infiltrating lymphocytes (TILs) in HPVDNA+ p16(INK4a+) TSCC indicated a better outcome. Here this study was extended. Totally 203 TSCC and 77 BOTSCC formalin fixed paraffin embedded tumour biopsies, earlier tested for HPV DNA (79% HPVDNA+) and p16(INK4a) from patients treated with curative intention, were analysed for CD8(+) and CD4(+) TILs by immunohistochemistry. Data obtained for 275 patients were correlated to HPVDNA and p16(INK4a) status, overall survival (OS) and disease free survival (DFS). In both HPVDNA+ and HPVDNA+ p16(INK4a+) tumours higher CD8(+) TIL counts correlated to a better 3-year OS (logrank test, both p<0.001) and 3-year DFS (logrank test, p = 0.003 and p = 0.004 respectively) as compared to the lowest quartile in the groups. A similar pattern was observed when analysing TSCC alone, while for BOTSCC significance was obtained only for 3-year OS. In HPVDNA- tumours the trend was similar, but significance was obtained again only for 3-year OS. The number of CD4(+) TILs did not generally correlate to survival. In conclusion, in HPVDNA+ and/or HPVDNA+ p16(INK4a+) tumours high CD8(+) TIL counts indicated a better 3-year OS. This suggests that high CD8(+) TIL counts together with HPVDNA+ or HPVDNA+ p16(INK4a+) could be used when selecting patients for more individualised treatment.

MHC class I expression in HPV positive and negative tonsillar squamous cell carcinoma in correlation to clinical outcome.

Human papillomavirus (HPV) is an important factor for the development of tonsillar squamous cell carcinoma (TSCC). In addition, patients with HPV-positive TSCC have a better clinical outcome than patients with HPV-negative TSCC. Although, HPV is an important prognostic marker, additional biomarkers are needed to better predict clinical outcome to individualize treatment. Hence, we examined if classical HLA HLA-A,B,C and nonclassical HLA-E,G could serve as such marker. Formalin-fixed paraffin-embedded TSCC from 150 patients diagnosed 2000-2006, earlier analyzed for HPV DNA and p16(INK4a), and treated with intention to cure were evaluated for the expression of HLA-A,B,C and HLA-E,G by immunohistochemistry. For HPV-positive TSCC a low expression of HLA-A,B,C, whereas for HPV-negative TSCC, a normal expression of HLA-A,B,C was significantly correlated to a favorable clinical outcome. These correlations were more pronounced for membrane staining of HLA-A,B,C when compared with cytoplasmatic staining. No significant correlation was found between HLA-E,G and HPV status or clinical outcome. The unexpected contrasting correlation between HLA-A,B,C expression, and clinical outcome depending on HPV, indicates essential differences between HPV-positive and HPV-negative TSCC. Furthermore, our data demonstrate that for both HPV-positive and HPV-negative TSCC, the expression of HLA-A,B,C together with HPV may serve as a useful biomarker for predicting clinical outcome.

Prevalence of oral human papillomavirus infection among youth, Sweden.

Human papillomavirus (HPV) causes cervical, head, and neck cancers. We studied 483 patients at a youth clinic in Stockholm, Sweden, and found oral HPV prevalence was 9.3% and significantly higher for female youth with than without cervical HPV infection (p = 0.043). Most oral HPV types matched the co-occurring cervical types.

Tumor infiltrating CD8+ and Foxp3+ lymphocytes correlate to clinical outcome and human papillomavirus (HPV) status in tonsillar cancer.

BACKGROUND: Human papillomavirus (HPV) is a causative factor for tonsillar squamous cell carcinoma (TSCC) and patients with HPV positive (HPV(+)) TSCC have a better clinical outcome than those with HPV negative (HPV(-)) TSCC. However, since not all patients with HPV(+) TSCC respond to treatment, additional biomarkers are needed together with HPV status to better predict response to therapy and to individualize treatment. For this purpose, we examined whether the number of tumor infiltrating cytotoxic and regulatory T-cells in TSCC correlated to HPV status and to clinical outcome. METHODS: Formalin fixed paraffin embedded TSCC, previously analysed for HPV DNA, derived from 83 patients, were divided into four groups depending on the HPV status of the tumor and clinical outcome. Tumors were stained by immunohistochemistry and evaluated for the number of infiltrating cytotoxic (CD8(+)) and regulatory (Foxp3(+)) T-cells. RESULTS: A high CD8(+) T-cell infiltration was significantly positively correlated to a good clinical outcome in both patients with HPV(+) and HPV(-) TSCC patients. Similarly, a high CD8(+)/Foxp3(+) TIL ratio was correlated to a 3-year disease free survival. Furthermore, HPV(+) TSCC had in comparison to HPV(-) TSCC, higher numbers of infiltrating CD8(+) and Foxp3(+) T-cells. CONCLUSIONS: In conclusion, a positive correlation between a high number of infiltrating CD8(+) cells and clinical outcome indicates that CD8(+) cells may contribute to a beneficial clinical outcome in TSCC patients, and may potentially serve as a biomarker. Likewise, the CD8(+)/Foxp3(+)cell ratio can potentially be used for the same purpose.

Human papillomavirus (HPV) 16 E6 variants in tonsillar cancer in comparison to those in cervical cancer in Stockholm, Sweden.

BACKGROUND: Human papillomavirus (HPV), especially HPV16, is associated with the development of both cervical and tonsillar cancer and intratype variants in the amino acid sequence of the HPV16 E6 oncoprotein have been demonstrated to be associated with viral persistence and cancer lesions. For this reason the presence of HPV16 E6 variants in tonsillar squamous cell carcinoma (TSCC) in cervical cancer (CC), as well as in cervical samples (CS), were explored. METHODS: HPV16 E6 was sequenced in 108 TSCC and 52 CC samples from patients diagnosed 2000-2008 in the County of Stockholm, and in 51 CS from young women attending a youth health center in Stockholm. RESULTS: The rare E6 variant R10G was relatively frequent (19%) in TSCC, absent in CC and infrequent (4%) in CS, while the well-known L83V variant was common in TSCC (40%), CC (31%), and CS (29%). The difference for R10G was significant between TSCC and CC (p = 0.0003), as well as between TSCC and CS (p = 0.009). The HPV16 European phylogenetic lineage and its derivatives dominated in all samples (>90%). CONCLUSION: The relatively high frequency of the R10G variant in TSCC, as compared to what has been found in CC both in the present study as well as in several other studies in different countries, may indicate a difference between TSCC and CC with regard to tumor induction and development. Alternatively, there could be differences with regard to the oral and cervical prevalence of this variant that need to be explored further.

BRIP1, PALB2, and RAD51C mutation analysis reveals their relative importance as genetic susceptibility factors for breast cancer.

Mutations in the recognized breast cancer susceptibility genes BRCA1, BRCA2, TP53, ATM, and CHEK2 account for approximately 20% of hereditary breast cancer. This raises the possibility that mutations in other biologically relevant genes may be involved in genetic predisposition to breast cancer. In this study, BRIP1, PALB2, and RAD51C were sequenced for mutations as a result of previously being associated with breast cancer risk due to their role in the double-strand break repair pathway and their close association with BRCA1 and BRCA2. Two truncating mutations in PALB2 (Q66X and W1038X), one of which is has not been reported before, were detected in an independent Australian cohort of 70 individuals with breast or ovarian cancer, and have strong family histories of breast or breast/ovarian cancer. In addition, six missense variants predicted to be causative were detected, one in BRIP1 and five in PALB2. No causative variants were identified in RAD51C. This study supports recent observations that although rare, PALB2 mutations are present in a small but substantial proportion of inherited breast cancer cases, and indicates that RAD51C at a population level does not account for a substantial number of familial breast cancer cases.