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- Holm, Anna M., 1989-
(författare)
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Human papillomavirus in sinonasal inverted papilloma, recurrent respiratory papilloma and non-malignant tonsils
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Human papillomavirus (HPV) is known to cause recurrent respiratory papilloma (RRP) and certain types of oropharyngeal cancer. HPV has also been associated with sinonasal inverted papilloma (SIP). HPV transmission routes are under investigation and the conviction is that the infection occurs sexually at an adult stage, however, vertical transmission at birth with a dormant viral condition until disease eruption/co-activation has been stated as a possibility.Purpose: The purpose of this work was to contribute to the understanding of HPV related chronic diseases in the airway. Specific aims were: 1. To increase understanding regarding changes in the immune system as well as of the glycosaminoglycan hyaluronan in patients with RRP. 2. To evaluate prevalence of HPV and its surrogate marker p16 in SIP as well as HPV, p16 and Epstein-Barr virus (EBV) in benign tonsillar disease. HPV and EBV in non-malignant tonsillar disease were studied due to the fact that incidence of HPV positive tonsillar cancer is increasing and the time of viral infection is unknown.Methods: A phenotypic characterization of peripheral blood from 16 RRP patients and 12 age-matched controls, using immunoflow cytometry, and monoclonal antibodies against differentiation and activation markers, was performed. The cytokine mRNA profile of monocytes, T helper-, T cytotoxic-, and NK cells was assessed using RT-qPCR. 54 SIP samples were studied of which 53 were available for analyzation with PCR. Genotype screening for 18 high risk and six low risk HPV types was performed using the PapilloCheck® HPV-screening test (a PCR method). 54 samples were immunohistochemically (IHC) stained for p16. Biopsies from vocal folds (VFs) and false vocal folds (FVFs) were collected from 24 patients with RRP, 12 were randomly selected to histochemistry for Hyaluronan (HA) and IHC staining for CD44 in the epithelium, stroma and RRP lesions. The remaining 12 patients were analyzed for HA molecular mass distribution with a gas-phase electrophoretic molecular mobility analyzer (GEMMA). Eight VF samples and four FVF samples were successfully analyzed. Biopsies from 40 non-malignant tonsils were analyzed using Papillocheck® for HPV, IHC for p16 and EBER analysis for EBV.Results: We found a dominance of cytotoxic T cells, activated NK cells, and high numbers of stressed MIC A/B (MHC class I chain-related molecule A/B) expressing lymphocytes. The HPV analysis was successful for 38 SIP samples and two (5%) were positive for HPV 11. Notably, p16 was present in the epithelia of all samples and in the papilloma portions in 37 of 38 samples. We found extensive HA staining in the stroma of both VFs and FVFs. CD44 was expressed throughout the epithelium, stroma, and RRP lesions in both FVFs and VFs, it did however, not concur with the expression of HA. Very high mass HA was found in both VFs and FVFs, though more variation regarding amounts of HA was seen in the VFs compared to FVFs. No HPV was found in non-malignant tonsils, the p16 levels were low and the counted EBER positive cells showed great variation in numbers.Conclusions: Our findings demonstrate an immune dysregulation with inverted CD4+/CD8+ ratio and aberrant cytokine mRNA production in RRP patients, compared to healthy controls. We concluded that p16 cannot be used as a surrogate marker for high-risk HPV-infection in SIP and that HPV incidence was low (5%). CD44 does not seem to bind to HA, which might explain the noninflammatory response previously described in RRP. Very high mass HA possibly crosslinked was seen in both VFs and FVFs. A possibility to counteract inflammatory crosslinking of HA may be found for medical treatment options in RRP.
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| 2. |
- Li, Xingru, 1987-
(författare)
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Wilms' tumor gene 1 in different types of cancer
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Wilms’ tumor gene 1 (WT1) was first reported as a tumor suppressor gene in Wilms’ tumor. However, later studies have shown the oncogenic properties of WT1 in a variety of tumors. It was recently proposed that WT1 was a chameleon gene, due to its dual functions in tumorigenesis. We aimed to investigate the clinical significance of WT1 as biomarker in acute myeloid leukemia (AML) and clear cell renal cell carcinoma (ccRCC) and to elucidate the function of WT1 as an oncogene in squamous cell carcinoma of head and neck (SCCHN).In AML, it was suggested that WT1 expression was an applicable marker of minimal residual disease (MRD). In adult patients with AML, we found a good correlation between WT1 expression levels normalized to two control genes, β-actin and ABL. Outcome could be predicted by a reduction in WT1 expression in bone marrow (≥ 1-log) detected less than 1 month after diagnosis, when β-actin was used as control. Also, irrespective of the control gene used, outcome could be predicted by a reduction in WT1 expression in peripheral blood (≥ 2-log) detected between 1 and 6 months after treatment initiation.Previous studies in RCC demonstrated that WT1 acted as a tumor suppressor. Thus, we tested whether single nucleotide polymorphisms (SNPs) or mutations in WT1 might be associated with WT1 expression and clinical outcome in patients with ccRCC. We performed sequencing analysis on 10 exons of the WT1 gene in a total of 182 patient samples, and we identified six different SNPs in the WT1 gene. We found that at least one or two copies of the minor allele were present in 61% of ccRCC tumor samples. However, no correlation was observed between WT1 SNP genotypes and RNA expression levels. Moreover, none of the previously reported WT1 mutations were found in ccRCC. Nevertheless, we found that a favorable outcome was associated the homozygous minor allele for WT1 SNP. We then further investigated whether WT1 methylation was related to WT1 expression and its clinical significance. Methylation array and pyrosequencing analyses showed that the WT1 promoter region CpG site, cg22975913, was the most frequently hypermethylated CpG site. We found a trend that showed nearly significant correlation between WT1 mRNA levels and hypermethylation in the 5’-untranslated region. Hypermethylation in the WT1 CpG site, cg22975913, was found to be associated with patient age and a worse prognosis.One previous study reported that WT1 was overexpressed in SCCHN. That finding suggested that WT1 might play a role in oncogenesis. We found that both WT1 and p63 could promote cell proliferation. A positive correlation between WT1 and p63 expression was observed, and we identified p63 as a WT1 target gene. Furthermore, several known WT1 and p63 target genes were affected by knocking down WT1. Also, co-immunoprecipitation analyses demonstrated a protein interaction between WT1 and p53.In summary, WT1 gene expression can provide useful information for MRD detection during treatment of patients with AML. In RCC, our results suggested that the prognostic impact of WT1 SNPs was limited to the subgroup of patients that were homozygous for the minor allele, and that WT1 promoter hypermethylation could be used as a prognostic biomarker. In SCCHN, WT1 and p63 acted as oncogenes by affecting multiple genes involved in cancer cell growth.
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| 3. |
- Loizou, Christos, 1980-
(författare)
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Human papillomavirus in recurrent respiratory papillomatosis, tonsillar and mobile tongue cancer
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on the effects of the human papillomavirus (HPV) in tonsillar cancer, mobile tongue cancer, and recurrent respiratory papillomatosis (RRP). The purpose was to characterize patients with RRP in northern Sweden in order to identify more care-intensive RRP patients and to describe the voice and quality of life aspects that follow RRP. Further aims were to confirm the expected increase of HPV-positive tonsillar cancer cases in northern Sweden, and to study the correlation between HPV, its surrogate marker p16 and HPV receptor syndecan-1 in both tonsillar cancer and mobile tongue cancer.A total of 27 consecutive patients with RRP were evaluated at 3 months postoperatively using the voice handicap index (VHI) and SF-36 questionnaires to assess the impact on life and voice in a RRP population. The values were compared to normative data. This report was further extended by examining consecutive data from 21 new patients in order to characterize RRP patients in northern Sweden. In order to study HPV DNA in tonsillar (n= 65) and mobile tongue cancer (n=109), HPV DNA was extracted from paraffin-embedded biopsies and detected by polymerase chain reaction using general primers Gp5+/6+ and CpI/IIG. Expression of HPV surrogate marker p16 and the HPV receptor syndecan-1 was analysed by immunohistochemistry.Patients that underwent more than one RRP surgery per year were younger than those treated less frequently and they had significantly impaired voice quality as compared to normal subjects. Females, patients with frequent surgical treatment sessions, and patients with the high-risk HPV subtypes scored significantly lower in several domains of the quality of life assessment as compared with normal subjects. Forty-eight RRP patients had a median age of 44.5 years; 71% were men and 29% females, preferentially infected with HPV6. Patients with high surgical treatment frequency/year showed more widespread RRP in the larynx compared to the patients treated less frequently.A total of 214 tonsillar cancer cases were identified. The vast majority were men. They had a median age of 58 years at diagnosis and expressed HPV as well as p16. The incidence of tonsillar cancer revealed a 2,7-fold increase in men between the years 1990 and 2013. The study demonstrates a strong association between p16 and HPV infection in tonsillar malignancies. These findings are in contrast to the mobile tongue cancer cases, where no evidence of HPV DNA could be detected although one-third showed p16 staining. This demonstrated a poor correlation between HPV and p16 in mobile tongue cancer. There was no difference in the expression of the primary HPV receptor, syndecan-1, between tonsillar and mobile tongue cancer.In conclusion, the frequency of RRP operations, age at onset, gender and subtype of the HPV may be used as factors to predict voice disability. RRP patients with high surgical treatment frequency were significantly younger and had a more widespread laryngeal disease compared to the low-frequency treated group. This study confirms the existence of a clinical RRP group, not primarily related to HPV subtype, but to a more care-intensive RRP population. Our findings identify a 2,7-fold increase in the incidence of tonsillar cancer, HPV and p16 in men between 1990-2013. We can use p16 to detect HPV in tonsillar cancer but not in tongue cancer.The introduction of vaccination against HPV may have a role in the prevention of specific HPV-subtype positive head and neck malignancies and recurrent respiratory papillomatosis since the current vaccine protects against HPV6, 11, 16, 18, 31, 33, 45, 52 and 58. Males will definitely benefit indirectly from vaccination of females, though males will still remain at risk of cancers associated with HPV. This highlights the need for sex-neutral vaccination strategy. Our intention is that this thesis will provide scientific data to support a gender-neutral vaccination and to develop simple tools to detect HPV in tonsillar cancer.
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