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Featured researches published by Andrea Vlastos.


European Journal of Cancer | 2015

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

Anders Näsman; Cecilia Nordfors; Stefan Holzhauser; Andrea Vlastos; Nikolaos Tertipis; Ulf Hammar; Lalle Hammarstedt-Nordenvall; Linda Marklund; Eva Munck-Wikland; Torbjörn Ramqvist; Matteo Bottai; Tina Dalianis

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.


Cancer Medicine | 2014

Human papillomavirus and p53 expression in cancer of unknown primary in the head and neck region in relation to clinical outcome.

Lars Sivars; Anders Näsman; Nikolaos Tertipis; Andrea Vlastos; Torbjörn Ramqvist; Tina Dalianis; Eva Munck-Wikland; Sushma Nordemar

Patients with cancer of unknown primary (CUP) in the head neck region are generally treated with neck dissection followed by radiotherapy at times combined with chemotherapy, a treatment associated with considerable side effects. Some of these tumors may originate as human papillomavirus (HPV)‐positive oropharyngeal squamous cell carcinoma (OSCC), with better clinical outcome than head neck squamous cell cancer (HNSCC) in general, and could potentially do well with less treatment. Here, we therefore investigated whether HPV status and p53‐expression correlated to clinical outcome in patients with CUP in the head neck region. Fifty metastases were analyzed for presence of HPV DNA, and expression of p16INK4A and p53 and the data were correlated to clinical outcome. Patients with HPV DNA‐positive (HPVDNA+) metastases had significantly better 5‐year overall survival (OS) compared to those with HPVDNA− metastases (80.0% vs. 36.7%, respectively; P = 0.004), with a similar tendency for disease‐free survival (DFS). These survival rates showed excellent concordance with those of HPVDNA+ and HPVDNA− OSCC in Sweden during the same time period, strengthening the hypothesis that HPVDNA+ head and neck CUP may originate from HPVDNA+ OSCC. In addition, having absent/intermediary‐low as compared to high expression of p53 correlated to a better prognosis with a 69% as compared to 14% 5‐year OS, respectively (P < 0.001), and for DFS the tendency was analogous. In conclusion, both HPV status and p53 expression are valuable prognostic factors in patients with CUP in the head and neck region and should be further explored for clinical use.


Vaccine | 2002

Immunization of T-cell deficient mice against polyomavirus infection using viral pseudocapsids or temperature sensitive mutants.

Shirin Heidari; Andrea Vlastos; Torbjörn Ramqvist; Barny Clark; Beverly E. Griffin; Marie-Isabelle Garcia; Marie Perez; Paolo Amati; Tina Dalianis

A murine experimental model system aimed at developing potential vaccines to papovavirus infection in immunosuppressed individuals was explored. A VP1-pseudocapsid based on the major capsid protein of the murine polyomavirus A2 strain and a mutant, M17-pseudocapsid as well as four temperature sensitive (ts)-mutants were used as immunogens. T-cells deficient CD4-/-8-/- mice were immunized four times with each immunogen and then together with non-immunized control mice challenged with polyomavirus. In contrast to all control mice, only half of the immunized mice exhibited presence of polyoma DNA when assayed by PCR. The results indicate that pseudocapsids and ts-mutant immunization may potentially protect mice with an impaired T-cell function from polyomavirus infection.


Oral Oncology | 2015

Human papillomavirus DNA and p16INK4a expression in hypopharyngeal cancer and in relation to clinical outcome, in Stockholm, Sweden

Tina Dalianis; Nathalie Grün; Jana Koch; Andrea Vlastos; Nikolaos Tertipis; Cecilia Nordfors; Anders Näsman; Malin Wendt; Mircea Romanitan; Cinzia Bersani; Eva Munck-Wikland; Torbjörn Ramqvist

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.


European Journal of Cancer | 2015

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

Nikolaos Tertipis; Ulf Hammar; Anders Näsman; Andrea Vlastos; Cecilia Nordfors; Nathalie Grün; Andreas Ährlund-Richter; Lars Sivars; Linnea Haeggblom; Linda Marklund; Lalle Hammarstedt-Nordenvall; Anil K. Chaturvedi; Eva Munck-Wikland; Torbjörn Ramqvist; Matteo Bottai; Tina Dalianis

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.


PLOS ONE | 2014

Correlation of LMP10 Expression and Clinical Outcome in Human Papillomavirus (HPV) Positive and HPV-Negative Tonsillar and Base of Tongue Cancer

Nikolaos Tertipis; Linnea Haeggblom; Cecilia Nordfors; Nathalie Grün; Anders Näsman; Andrea Vlastos; Tina Dalianis; Torbjörn Ramqvist

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.


Oral Oncology | 2017

A model using concomitant markers for predicting outcome in human papillomavirus positive oropharyngeal cancer

Cinzia Bersani; Michael Mints; Nikolaos Tertipis; Linnea Haeggblom; Lars Sivars; Andreas Ährlund-Richter; Andrea Vlastos; Cecilia Smedberg; Nathalie Grün; Eva Munck-Wikland; Anders Näsman; Torbjörn Ramqvist; Tina Dalianis

OBJECTIVE Head-neck cancer therapy has become intensified. With radiotherapy alone, 3-year disease-free survival (DFS) is 80% for HPV-positive TSCC/BOTSCC and better for patients with favorable characteristics, suggesting therapy could be tapered for some, decreasing side-effects. Therefore, we built a model to predict progression-free survival for patients with HPV-positive TSCC and BOTSCC. MATERIAL AND METHODS TSCC/BOTSCC patients treated curatively between 2000 and 2011, with HPV16 DNA/E7 mRNA positive tumors examined for CD8+ TILs, HPV16 mRNA and HLA class I expression were included. Patients were split randomly 65/35 into training and validation sets, and LASSO regression was used to select a model in the training set, the performance of which was evaluated in the validation set. RESULTS 258 patients with HPV DNA/E7 mRNA positive tumors could be included, 168 and 90 patients in the respective sets. No treatment improved prognosis compared to radiotherapy alone. CD8+ TIL counts and young age were the strongest predictors of survival, followed by T-stage <3 and presence of HPV16 E2 mRNA. The model had an area under curve (AUC) of 76%. A model where the presence of three of four of these markers defined good prognosis captured 56% of non-relapsing patients with a positive predictive value of 98% in the validation set. Furthermore, the model identified 35% of our cohort that was overtreated and could safely have received de-escalated therapy. CONCLUSION CD8+ TIL counts, age, T-stage and E2 expression could predict progression-free survival, identifying patients eligible for randomized trials with milder treatment, potentially reducing side effects without worsening prognosis.


Virology | 2014

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

Maria Bradley; Cecilia Nordfors; Andrea Vlastos; Giovanni Ferrara; Torbjörn Ramqvist; Tina Dalianis

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.


Oral Oncology | 2014

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

Cecilia Nordfors; Andrea Vlastos; Juan Du; Andreas Ährlund-Richter; Nikolaos Tertipis; Nathalie Grün; Mircea Romanitan; Linnea Haeggblom; Ann Roosaar; Göran Dahllöf; Maria Gabriella Donà; Maria Benevolo; Torbjörn Ramqvist; Eva Munck-Wikland; Tina Dalianis


Journal of General Virology | 2003

Murine pneumotropic virus VP1 virus-like particles (VLPs) bind to several cell types independent of sialic acid residues and do not serologically cross react with murine polyomavirus VP1 VLPs

Karin Tegerstedt; Kalle Andreasson; Andrea Vlastos; Kjell-Olof Hedlund; Tina Dalianis; Torbjörn Ramqvist

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Eva Munck-Wikland

Karolinska University Hospital

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