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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Educational Intervention for Engaging Adolescents and Their Parents in HPV Vaccination

Mena Cantero, Alvin 01 January 2017 (has links)
In the United States, 79 million people are currently infected with Human Papilloma Virus (HPV) and it is estimated that an additional 14 to 20 million people will be infected with HPV every year. Infection with HPV increased to 52.7 % of preventable infections within the United States in 2012, and 39.6% of the infected population are adolescents engaged in sexual activities. The practice-focused question that this project addressed was: To what extent can an educational program influence the HPV vaccination rate in a small family practice clinic located in Texas? The main purpose of this project was to increase education within the clinic community using a quality improvement approach and guided by Healthy People Goals 2020. Barriers to HPV vaccination were validated through focus group discussion held with clinic staff. Parental resistance was due to a misconception that the vaccine would lead to sexual promiscuity in the adolescent population, and that a single dose is adequate protection. A bilingual educational session was held with 15 clinic staff members with the purpose of enhancing knowledge, influencing parental attitudes and beliefs, providing patient educational tools, and thereby increasing vaccination acceptance by 37.8% within an underserved and vulnerable population. The results of the focus group and educational sessions were presented to an expert panel made up of five community leaders and the senior clinic leader who approved the approach and suggested additional ways to promote HPV vaccination. Clinic leadership agreed to adjust policy mandating use of the educational materials with clinic patients. Positive social change will result from the integration of this educational approach into clinic practice by increasing vaccination acceptance.
12

Role of SerpinB2 in tumour cells

Lee Major Unknown Date (has links)
SerpinB2 (aka plasminogen activator type 2) is well described as an extracellular inhibitor of urokinase-type plasminogen activator (uPA). However, the majority of SerpinB2 is retained intracellularly, and many uPA-independent activities have been reported for SerpinB2 suggesting an alternate function. This thesis explores the role of SerpinB2 in epithelial tumour cell lines, highlights the problems associated with various expression systems and argues that SerpinB2 has no role in growth or apoptosis of tumour cells. A potential role for immune modulation and angiogenesis is suggested in in vivo models. Previous research using SerpinB2 transfected, clonally selected tumour cell lines suggested that SerpinB2 regulates the retinoblastoma tumour suppressor protein (Rb) by binding and protecting Rb from degradation. Despite the use of two techniques under numerous conditions and positive controls, no significant interaction between SerpinB2 and Rb was found. SerpinB2 was reported to bind Rb through a PENF homology motif located within the SerpinB2 C-D interhelical loop region. The PENF homology motif was postulated to represent the motif responsible for binding to the C-pocket of Rb. Epstein Barr Virus nuclear antigen 6 (EBNA6) is a known Rb binding protein, which contains two predicted PENF homology motifs. However, mutation of the two PENF homology motifs within EBNA6 did not reduce Rb binding. Furthermore, the SerpinB2 PENF homology motif is actually not well conserved between SerpinB2 proteins from multiple species, whereas other regions of the SerpinB2 C-D loop show a high level of conservation. These data do not support a role for SerpinB2 and the PENF homology motif in Rb binding. SerpinB2 has been proposed to have a role in regulating growth and apoptosis. To further investigate this proposed phenotype of SerpinB2, SerpinB2 was expressed in a range of epithelial tumour lines using transient transfection. No change in growth, apoptosis or Rb levels were found. After ≈2-3 month antibiotic selection for the SerpinB2-expressing plasmid, SerpinB2 protein was lost without the loss of the transgene, indicating selective pressure against long-term SerpinB2 protein expression. To further investigate long-term SerpinB2 expression adenovirus and lentivirus vectors were used. Infection of tumour cell lines with adenovirus vectors expressing SerpinB2 resulted in reduced cell growth, characterised by increased p53 (but not Rb) levels and G2 arrest or apoptosis. When SerpinB2 expressing lentivirus vectors were used to transduce the same tumour cell lines, high levels of long-term expression of functional SerpinB2 was achieved. However, SerpinB2-expressing cell lines showed no differences in growth, proliferation, Rb levels, or apoptosis induced by a range of agents. Growth and apoptosis observed with adenovirus SerpinB2 had all the characteristics of adenovirus-associated toxicity, which has been reported previously for specific proteins. These experiments highlighted the problems associated with SerpinB2 expression systems and suggest that SerpinB2 expression per se is not toxic nor has a role in regulating Rb, growth and apoptosis. Screening of a number of tumour cell lines identified the HPV16 transformed cervical cancer line as expressing high levels of SerpinB2. SerpinB2 was located both extracellularly and intracellularly with a cytoplasmic and nuclear distribution. A high molecular weight SerpinB2 species was identified in CaSki cells and was shown to be the N-linked glycosylated species. Sequencing showed the protein to be Type A SerpinB2 and the protein was shown to form an inhibitory complex with uPA. An abundant low molecular weight SerpinB2 species was also identified in CaSki cell supernatants and appeared to be a proteolytic fragment of SerpinB2. Treatment of CaSki with PMA, TNFα and IFNγ increased SerpinB2 levels. Lentiviral based shRNA failed to significantly down regulate SerpinB2 expression and increasing SerpinB2 levels with lentiviral expression did not change growth, apoptosis, Rb levels or E7 transcription. Lentiviral expression of SerpinB2 in (normally SerpinB2 negative) HPV16 transformed SiHa cells, also failed to show changes in Rb levels or E7 transcription. CaSki thus express wild-type and functional SerpinB2, but no evidence could found that SerpinB2 effects HPV16 E7 transcription or Rb levels. The data presented identifies CaSki as valuable source of biologically functional SerpinB2. SerpinB2 expression in breast cancer cells has been associated with positive prognosis. Tubo, a SerpinB2-negative murine breast carcinoma cell line, was transduced with lentivirus expressing SerpinB2 and grown subcutaneously in BALB/c mice. SerpinB2 expressing tumours appeared red and were larger than control tumours. Furthermore, SerpinB2 expressing tumours had a ≈2 fold higher density of blood vessels when compared to Tubo and Tubo expressing EGFP. Mice carrying tumours expressing SerpinB2 also showed reduced anti-tumour IgG2 responses. These data suggest that a role for SerpinB2 in regulating angiogenesis and antitumour immunity. In conclusion, this thesis challenges the notion that SerpinB2 regulates Rb, cell cycle, and apoptosis and suggests a potential role for SerpinB2 in tumour angiogenesis and immunity.
13

Role of SerpinB2 in tumour cells

Lee Major Unknown Date (has links)
SerpinB2 (aka plasminogen activator type 2) is well described as an extracellular inhibitor of urokinase-type plasminogen activator (uPA). However, the majority of SerpinB2 is retained intracellularly, and many uPA-independent activities have been reported for SerpinB2 suggesting an alternate function. This thesis explores the role of SerpinB2 in epithelial tumour cell lines, highlights the problems associated with various expression systems and argues that SerpinB2 has no role in growth or apoptosis of tumour cells. A potential role for immune modulation and angiogenesis is suggested in in vivo models. Previous research using SerpinB2 transfected, clonally selected tumour cell lines suggested that SerpinB2 regulates the retinoblastoma tumour suppressor protein (Rb) by binding and protecting Rb from degradation. Despite the use of two techniques under numerous conditions and positive controls, no significant interaction between SerpinB2 and Rb was found. SerpinB2 was reported to bind Rb through a PENF homology motif located within the SerpinB2 C-D interhelical loop region. The PENF homology motif was postulated to represent the motif responsible for binding to the C-pocket of Rb. Epstein Barr Virus nuclear antigen 6 (EBNA6) is a known Rb binding protein, which contains two predicted PENF homology motifs. However, mutation of the two PENF homology motifs within EBNA6 did not reduce Rb binding. Furthermore, the SerpinB2 PENF homology motif is actually not well conserved between SerpinB2 proteins from multiple species, whereas other regions of the SerpinB2 C-D loop show a high level of conservation. These data do not support a role for SerpinB2 and the PENF homology motif in Rb binding. SerpinB2 has been proposed to have a role in regulating growth and apoptosis. To further investigate this proposed phenotype of SerpinB2, SerpinB2 was expressed in a range of epithelial tumour lines using transient transfection. No change in growth, apoptosis or Rb levels were found. After ≈2-3 month antibiotic selection for the SerpinB2-expressing plasmid, SerpinB2 protein was lost without the loss of the transgene, indicating selective pressure against long-term SerpinB2 protein expression. To further investigate long-term SerpinB2 expression adenovirus and lentivirus vectors were used. Infection of tumour cell lines with adenovirus vectors expressing SerpinB2 resulted in reduced cell growth, characterised by increased p53 (but not Rb) levels and G2 arrest or apoptosis. When SerpinB2 expressing lentivirus vectors were used to transduce the same tumour cell lines, high levels of long-term expression of functional SerpinB2 was achieved. However, SerpinB2-expressing cell lines showed no differences in growth, proliferation, Rb levels, or apoptosis induced by a range of agents. Growth and apoptosis observed with adenovirus SerpinB2 had all the characteristics of adenovirus-associated toxicity, which has been reported previously for specific proteins. These experiments highlighted the problems associated with SerpinB2 expression systems and suggest that SerpinB2 expression per se is not toxic nor has a role in regulating Rb, growth and apoptosis. Screening of a number of tumour cell lines identified the HPV16 transformed cervical cancer line as expressing high levels of SerpinB2. SerpinB2 was located both extracellularly and intracellularly with a cytoplasmic and nuclear distribution. A high molecular weight SerpinB2 species was identified in CaSki cells and was shown to be the N-linked glycosylated species. Sequencing showed the protein to be Type A SerpinB2 and the protein was shown to form an inhibitory complex with uPA. An abundant low molecular weight SerpinB2 species was also identified in CaSki cell supernatants and appeared to be a proteolytic fragment of SerpinB2. Treatment of CaSki with PMA, TNFα and IFNγ increased SerpinB2 levels. Lentiviral based shRNA failed to significantly down regulate SerpinB2 expression and increasing SerpinB2 levels with lentiviral expression did not change growth, apoptosis, Rb levels or E7 transcription. Lentiviral expression of SerpinB2 in (normally SerpinB2 negative) HPV16 transformed SiHa cells, also failed to show changes in Rb levels or E7 transcription. CaSki thus express wild-type and functional SerpinB2, but no evidence could found that SerpinB2 effects HPV16 E7 transcription or Rb levels. The data presented identifies CaSki as valuable source of biologically functional SerpinB2. SerpinB2 expression in breast cancer cells has been associated with positive prognosis. Tubo, a SerpinB2-negative murine breast carcinoma cell line, was transduced with lentivirus expressing SerpinB2 and grown subcutaneously in BALB/c mice. SerpinB2 expressing tumours appeared red and were larger than control tumours. Furthermore, SerpinB2 expressing tumours had a ≈2 fold higher density of blood vessels when compared to Tubo and Tubo expressing EGFP. Mice carrying tumours expressing SerpinB2 also showed reduced anti-tumour IgG2 responses. These data suggest that a role for SerpinB2 in regulating angiogenesis and antitumour immunity. In conclusion, this thesis challenges the notion that SerpinB2 regulates Rb, cell cycle, and apoptosis and suggests a potential role for SerpinB2 in tumour angiogenesis and immunity.
14

Factors influencing women's intentions to obtain the Human Papillomavirus (HPV) vaccine / Faktorer som påverkar kvinnors avsikt till att vaccinera sig mot humant papillomvirus (HPV) : en litteraturöversikt

Ebertz, Barika January 2013 (has links)
Background: Cervical cancer is second most common cancer in women. The 15% incidence of cervical cancer in women worldwide can potentially be reduced by the vaccine against human papillomavirus (HPV). It is therefore important for all healthcare professionals including registered nurses to understand what affects women’s intentions and willingness to receive HPV vaccination so that they can overcome any inappropriate barriers and promote public health. Aim: The aim of this article was to describe factors influencing women’s intentions to obtain the HPV vaccine. Method: The following databases Cinahl, Medline, PsycINFO, Summon @ HKR and Pubmed were searched for articles that studied factors influencing women’s intention to obtain the HPV vaccine. Ten studies met the inclusion criteria, five qualitative and five quantitative. Results:  Four main categories were identified that influenced women’s intention to obtain the HPV vaccine: knowledge, attitudes, the influence of other people and the safety of the vaccine. Discussion: Better access for women to accurate information is the key to increase women’s intention to obtain the HPV vaccine and improving public health. Conclusion: Correct information about HPV and HPV virus is needed to increase women’s intention to obtain the vaccine. / Bakgrund: Cervixcancer är den näst vanligaste cancern hos kvinnor med en global incidens på15 %. Cervixcancer leder till hög mortalitet. Genom Humant Papillomvirus (HPV)-vaccinering kan incidensen minskas kraftigt. Vaccintäckningen är suboptimal på många plaster i världen. Det är viktigt att vårdpersonal, inklusive sjuksköterskor, förstår vilka faktorer som påverkar viljan och beslutet att vaccinera sig. På så sätt kan sjukvårdspersonal påverka dessa beslut och faktorer och därigenom öka vaccinationstäckningen i befolkningen. Syfte: Syftet var att beskriva faktorer som påverkar kvinnors avsikt till att vaccinera sig mot HPV. Metod: I denna allmänna litteraturstudie användes databaserna Cinahl, Medline, PsycINFO, Summon @ HKR and Pubmed för att söka efter artiklar som studerade faktorer som påverkar kvinnor att vaccinera sig mot HPV. Totalt tio artiklar inkluderades, fem kvalitativa och fem kvantitativa studier. Resultat: Fyra huvudkategorier identifierades som påverkade kvinnor att vaccinera sig mot HPV: Kunskap, attityder, andras inflytande och vaccinets säkerhet. Diskussion: Bättre tillgång till korrekt information för kvinnor om HPV-vaccinet är nyckeln till att öka kvinnors avsikt att vaccinera sig och på så sätt förbättra folkhälsan. Slutsats: Det krävs korrekt information om HPV virus och vaccin för att öka kvinnors avsikt till att vaccinera sig.
15

Knowledge of Human Papilloma Virus, Cervical Cancer and Cytological Screening and Attitudes towards and Practices of Screening among Undergraduate students at Rajarata University, Sri Lanka : A cross-sectional study

Östh, Josefine January 2015 (has links)
Aim The burden of cervical cancer in Sri Lanka is high and research is limited. The objective was to describe the knowledge of Human Papilloma Virus (HPV), cervical cancer and its cytological screening, as well as worry of HPV and attitudes towards and practices of screening among undergraduate students at Rajarata University of Sri Lanka, Mihintale. Methods A cross-sectional study was conducted in January 2015 at Rajarata University, using a self-administrated questionnaire containing socio-demographics, knowledge, attitudes and practices (KAP). Male and female undergraduates, 18-30 years, were eligible. Knowledge was assessed by a numerical sum score ranging from 0 to 13, with 13 as maximum. Analyses were performed using ANOVA or Kruskal-Wallis tests. Results 326 students answered the questionnaire that revealed limited knowledge on cervical cancer, HPV and screening, with a mean score of 5.34 (SD 3.33). Knowledge was higher among older, medical students in the fifth year, however there was a high correlation between these variables. Knowledge was lower among management students. Most students were uncertain about the questions in the attitude section. A majority of students would be worried if they got infected with HPV. Screening practices were low (0.45 %). Approximately half of the women would consider cytological screening in the future. Conclusion The limited knowledge, low screening practices and high worry imply a need for information and awareness programs. Further research is needed in order to fully understand the delicacy of this public health threat for Sri Lankan women.
16

Significance of Human Papillomavirus (HPV) Analysis for the Detection of Precancerous Cervical Lesions : Impact of Self Sampling

Sanner, Karin January 2013 (has links)
Cervical cancer is the second most common cancer, with about 500 000 new cases per year among women worldwide. With a well-organized screening programme the number of cases can be reduced by more than 50%. In spite of having such a screening programme there are still around 450 new cases yearly in Sweden. The majority of these cases occur in non-attendees. There is thus a need to improve the Swedish cervical cancer screening programme in order to further reduce the number of cases of cervical cancer. Cervical cancer and high-grade cervical dysplasia are caused by sexually transferred high-risk human papillomaviruses (HR-HPVs). In cases of persistent HR-HPV infection there is a risk of development of dysplasia and in some cases subsequent progress to cervical cancer. HR-HPV testing shows high sensitivity as regards the detection of cervical dysplasia. Self-sampling of vaginal fluid for the analysis of HR-HPV has many advantages, since a woman can perform the sampling herself in a private setting, whenever suitable, without the need to travel to a clinic. Our studies have shown that sensitivity in the detection of precancerous lesions is about twice as great with the HR-HPV self-test compared with cytology-based tests.  If a woman was HR-HPV-positive in two consecutive tests, the specificity of the HR-HPV test increased to about 98%. Among women with short-term persistent HR-HPV infection, the prevalence of CIN 2+ was over 40%. There was good concordance in sensitivity as regards the detection of CIN 2+ between self-obtained and physician-obtained samples, although self-sampling was associated with slightly lower specificity. The prevalence of HR-HPV from day to day in premenopausal women was not influenced by hormonal changes during the menstrual cycle. Neither were there significant day-to-day changes in postmenopausal women. A single self-test thus provides reliable information on whether or not a woman has an HR-HPV infection. In conclusion, self-sampling combined with the analysis of HR-HPV appears to be a powerful alternative as a primary screening method for the prevention of cervical cancer. Self-sampling for HR-HPV testing is a suitable, safe and accepted strategy for cervical cancer prevention among women.
17

Role of SerpinB2 in tumour cells

Lee Major Unknown Date (has links)
SerpinB2 (aka plasminogen activator type 2) is well described as an extracellular inhibitor of urokinase-type plasminogen activator (uPA). However, the majority of SerpinB2 is retained intracellularly, and many uPA-independent activities have been reported for SerpinB2 suggesting an alternate function. This thesis explores the role of SerpinB2 in epithelial tumour cell lines, highlights the problems associated with various expression systems and argues that SerpinB2 has no role in growth or apoptosis of tumour cells. A potential role for immune modulation and angiogenesis is suggested in in vivo models. Previous research using SerpinB2 transfected, clonally selected tumour cell lines suggested that SerpinB2 regulates the retinoblastoma tumour suppressor protein (Rb) by binding and protecting Rb from degradation. Despite the use of two techniques under numerous conditions and positive controls, no significant interaction between SerpinB2 and Rb was found. SerpinB2 was reported to bind Rb through a PENF homology motif located within the SerpinB2 C-D interhelical loop region. The PENF homology motif was postulated to represent the motif responsible for binding to the C-pocket of Rb. Epstein Barr Virus nuclear antigen 6 (EBNA6) is a known Rb binding protein, which contains two predicted PENF homology motifs. However, mutation of the two PENF homology motifs within EBNA6 did not reduce Rb binding. Furthermore, the SerpinB2 PENF homology motif is actually not well conserved between SerpinB2 proteins from multiple species, whereas other regions of the SerpinB2 C-D loop show a high level of conservation. These data do not support a role for SerpinB2 and the PENF homology motif in Rb binding. SerpinB2 has been proposed to have a role in regulating growth and apoptosis. To further investigate this proposed phenotype of SerpinB2, SerpinB2 was expressed in a range of epithelial tumour lines using transient transfection. No change in growth, apoptosis or Rb levels were found. After ≈2-3 month antibiotic selection for the SerpinB2-expressing plasmid, SerpinB2 protein was lost without the loss of the transgene, indicating selective pressure against long-term SerpinB2 protein expression. To further investigate long-term SerpinB2 expression adenovirus and lentivirus vectors were used. Infection of tumour cell lines with adenovirus vectors expressing SerpinB2 resulted in reduced cell growth, characterised by increased p53 (but not Rb) levels and G2 arrest or apoptosis. When SerpinB2 expressing lentivirus vectors were used to transduce the same tumour cell lines, high levels of long-term expression of functional SerpinB2 was achieved. However, SerpinB2-expressing cell lines showed no differences in growth, proliferation, Rb levels, or apoptosis induced by a range of agents. Growth and apoptosis observed with adenovirus SerpinB2 had all the characteristics of adenovirus-associated toxicity, which has been reported previously for specific proteins. These experiments highlighted the problems associated with SerpinB2 expression systems and suggest that SerpinB2 expression per se is not toxic nor has a role in regulating Rb, growth and apoptosis. Screening of a number of tumour cell lines identified the HPV16 transformed cervical cancer line as expressing high levels of SerpinB2. SerpinB2 was located both extracellularly and intracellularly with a cytoplasmic and nuclear distribution. A high molecular weight SerpinB2 species was identified in CaSki cells and was shown to be the N-linked glycosylated species. Sequencing showed the protein to be Type A SerpinB2 and the protein was shown to form an inhibitory complex with uPA. An abundant low molecular weight SerpinB2 species was also identified in CaSki cell supernatants and appeared to be a proteolytic fragment of SerpinB2. Treatment of CaSki with PMA, TNFα and IFNγ increased SerpinB2 levels. Lentiviral based shRNA failed to significantly down regulate SerpinB2 expression and increasing SerpinB2 levels with lentiviral expression did not change growth, apoptosis, Rb levels or E7 transcription. Lentiviral expression of SerpinB2 in (normally SerpinB2 negative) HPV16 transformed SiHa cells, also failed to show changes in Rb levels or E7 transcription. CaSki thus express wild-type and functional SerpinB2, but no evidence could found that SerpinB2 effects HPV16 E7 transcription or Rb levels. The data presented identifies CaSki as valuable source of biologically functional SerpinB2. SerpinB2 expression in breast cancer cells has been associated with positive prognosis. Tubo, a SerpinB2-negative murine breast carcinoma cell line, was transduced with lentivirus expressing SerpinB2 and grown subcutaneously in BALB/c mice. SerpinB2 expressing tumours appeared red and were larger than control tumours. Furthermore, SerpinB2 expressing tumours had a ≈2 fold higher density of blood vessels when compared to Tubo and Tubo expressing EGFP. Mice carrying tumours expressing SerpinB2 also showed reduced anti-tumour IgG2 responses. These data suggest that a role for SerpinB2 in regulating angiogenesis and antitumour immunity. In conclusion, this thesis challenges the notion that SerpinB2 regulates Rb, cell cycle, and apoptosis and suggests a potential role for SerpinB2 in tumour angiogenesis and immunity.
18

Role of SerpinB2 in tumour cells

Lee Major Unknown Date (has links)
SerpinB2 (aka plasminogen activator type 2) is well described as an extracellular inhibitor of urokinase-type plasminogen activator (uPA). However, the majority of SerpinB2 is retained intracellularly, and many uPA-independent activities have been reported for SerpinB2 suggesting an alternate function. This thesis explores the role of SerpinB2 in epithelial tumour cell lines, highlights the problems associated with various expression systems and argues that SerpinB2 has no role in growth or apoptosis of tumour cells. A potential role for immune modulation and angiogenesis is suggested in in vivo models. Previous research using SerpinB2 transfected, clonally selected tumour cell lines suggested that SerpinB2 regulates the retinoblastoma tumour suppressor protein (Rb) by binding and protecting Rb from degradation. Despite the use of two techniques under numerous conditions and positive controls, no significant interaction between SerpinB2 and Rb was found. SerpinB2 was reported to bind Rb through a PENF homology motif located within the SerpinB2 C-D interhelical loop region. The PENF homology motif was postulated to represent the motif responsible for binding to the C-pocket of Rb. Epstein Barr Virus nuclear antigen 6 (EBNA6) is a known Rb binding protein, which contains two predicted PENF homology motifs. However, mutation of the two PENF homology motifs within EBNA6 did not reduce Rb binding. Furthermore, the SerpinB2 PENF homology motif is actually not well conserved between SerpinB2 proteins from multiple species, whereas other regions of the SerpinB2 C-D loop show a high level of conservation. These data do not support a role for SerpinB2 and the PENF homology motif in Rb binding. SerpinB2 has been proposed to have a role in regulating growth and apoptosis. To further investigate this proposed phenotype of SerpinB2, SerpinB2 was expressed in a range of epithelial tumour lines using transient transfection. No change in growth, apoptosis or Rb levels were found. After ≈2-3 month antibiotic selection for the SerpinB2-expressing plasmid, SerpinB2 protein was lost without the loss of the transgene, indicating selective pressure against long-term SerpinB2 protein expression. To further investigate long-term SerpinB2 expression adenovirus and lentivirus vectors were used. Infection of tumour cell lines with adenovirus vectors expressing SerpinB2 resulted in reduced cell growth, characterised by increased p53 (but not Rb) levels and G2 arrest or apoptosis. When SerpinB2 expressing lentivirus vectors were used to transduce the same tumour cell lines, high levels of long-term expression of functional SerpinB2 was achieved. However, SerpinB2-expressing cell lines showed no differences in growth, proliferation, Rb levels, or apoptosis induced by a range of agents. Growth and apoptosis observed with adenovirus SerpinB2 had all the characteristics of adenovirus-associated toxicity, which has been reported previously for specific proteins. These experiments highlighted the problems associated with SerpinB2 expression systems and suggest that SerpinB2 expression per se is not toxic nor has a role in regulating Rb, growth and apoptosis. Screening of a number of tumour cell lines identified the HPV16 transformed cervical cancer line as expressing high levels of SerpinB2. SerpinB2 was located both extracellularly and intracellularly with a cytoplasmic and nuclear distribution. A high molecular weight SerpinB2 species was identified in CaSki cells and was shown to be the N-linked glycosylated species. Sequencing showed the protein to be Type A SerpinB2 and the protein was shown to form an inhibitory complex with uPA. An abundant low molecular weight SerpinB2 species was also identified in CaSki cell supernatants and appeared to be a proteolytic fragment of SerpinB2. Treatment of CaSki with PMA, TNFα and IFNγ increased SerpinB2 levels. Lentiviral based shRNA failed to significantly down regulate SerpinB2 expression and increasing SerpinB2 levels with lentiviral expression did not change growth, apoptosis, Rb levels or E7 transcription. Lentiviral expression of SerpinB2 in (normally SerpinB2 negative) HPV16 transformed SiHa cells, also failed to show changes in Rb levels or E7 transcription. CaSki thus express wild-type and functional SerpinB2, but no evidence could found that SerpinB2 effects HPV16 E7 transcription or Rb levels. The data presented identifies CaSki as valuable source of biologically functional SerpinB2. SerpinB2 expression in breast cancer cells has been associated with positive prognosis. Tubo, a SerpinB2-negative murine breast carcinoma cell line, was transduced with lentivirus expressing SerpinB2 and grown subcutaneously in BALB/c mice. SerpinB2 expressing tumours appeared red and were larger than control tumours. Furthermore, SerpinB2 expressing tumours had a ≈2 fold higher density of blood vessels when compared to Tubo and Tubo expressing EGFP. Mice carrying tumours expressing SerpinB2 also showed reduced anti-tumour IgG2 responses. These data suggest that a role for SerpinB2 in regulating angiogenesis and antitumour immunity. In conclusion, this thesis challenges the notion that SerpinB2 regulates Rb, cell cycle, and apoptosis and suggests a potential role for SerpinB2 in tumour angiogenesis and immunity.
19

Role of SerpinB2 in tumour cells

Lee Major Unknown Date (has links)
SerpinB2 (aka plasminogen activator type 2) is well described as an extracellular inhibitor of urokinase-type plasminogen activator (uPA). However, the majority of SerpinB2 is retained intracellularly, and many uPA-independent activities have been reported for SerpinB2 suggesting an alternate function. This thesis explores the role of SerpinB2 in epithelial tumour cell lines, highlights the problems associated with various expression systems and argues that SerpinB2 has no role in growth or apoptosis of tumour cells. A potential role for immune modulation and angiogenesis is suggested in in vivo models. Previous research using SerpinB2 transfected, clonally selected tumour cell lines suggested that SerpinB2 regulates the retinoblastoma tumour suppressor protein (Rb) by binding and protecting Rb from degradation. Despite the use of two techniques under numerous conditions and positive controls, no significant interaction between SerpinB2 and Rb was found. SerpinB2 was reported to bind Rb through a PENF homology motif located within the SerpinB2 C-D interhelical loop region. The PENF homology motif was postulated to represent the motif responsible for binding to the C-pocket of Rb. Epstein Barr Virus nuclear antigen 6 (EBNA6) is a known Rb binding protein, which contains two predicted PENF homology motifs. However, mutation of the two PENF homology motifs within EBNA6 did not reduce Rb binding. Furthermore, the SerpinB2 PENF homology motif is actually not well conserved between SerpinB2 proteins from multiple species, whereas other regions of the SerpinB2 C-D loop show a high level of conservation. These data do not support a role for SerpinB2 and the PENF homology motif in Rb binding. SerpinB2 has been proposed to have a role in regulating growth and apoptosis. To further investigate this proposed phenotype of SerpinB2, SerpinB2 was expressed in a range of epithelial tumour lines using transient transfection. No change in growth, apoptosis or Rb levels were found. After ≈2-3 month antibiotic selection for the SerpinB2-expressing plasmid, SerpinB2 protein was lost without the loss of the transgene, indicating selective pressure against long-term SerpinB2 protein expression. To further investigate long-term SerpinB2 expression adenovirus and lentivirus vectors were used. Infection of tumour cell lines with adenovirus vectors expressing SerpinB2 resulted in reduced cell growth, characterised by increased p53 (but not Rb) levels and G2 arrest or apoptosis. When SerpinB2 expressing lentivirus vectors were used to transduce the same tumour cell lines, high levels of long-term expression of functional SerpinB2 was achieved. However, SerpinB2-expressing cell lines showed no differences in growth, proliferation, Rb levels, or apoptosis induced by a range of agents. Growth and apoptosis observed with adenovirus SerpinB2 had all the characteristics of adenovirus-associated toxicity, which has been reported previously for specific proteins. These experiments highlighted the problems associated with SerpinB2 expression systems and suggest that SerpinB2 expression per se is not toxic nor has a role in regulating Rb, growth and apoptosis. Screening of a number of tumour cell lines identified the HPV16 transformed cervical cancer line as expressing high levels of SerpinB2. SerpinB2 was located both extracellularly and intracellularly with a cytoplasmic and nuclear distribution. A high molecular weight SerpinB2 species was identified in CaSki cells and was shown to be the N-linked glycosylated species. Sequencing showed the protein to be Type A SerpinB2 and the protein was shown to form an inhibitory complex with uPA. An abundant low molecular weight SerpinB2 species was also identified in CaSki cell supernatants and appeared to be a proteolytic fragment of SerpinB2. Treatment of CaSki with PMA, TNFα and IFNγ increased SerpinB2 levels. Lentiviral based shRNA failed to significantly down regulate SerpinB2 expression and increasing SerpinB2 levels with lentiviral expression did not change growth, apoptosis, Rb levels or E7 transcription. Lentiviral expression of SerpinB2 in (normally SerpinB2 negative) HPV16 transformed SiHa cells, also failed to show changes in Rb levels or E7 transcription. CaSki thus express wild-type and functional SerpinB2, but no evidence could found that SerpinB2 effects HPV16 E7 transcription or Rb levels. The data presented identifies CaSki as valuable source of biologically functional SerpinB2. SerpinB2 expression in breast cancer cells has been associated with positive prognosis. Tubo, a SerpinB2-negative murine breast carcinoma cell line, was transduced with lentivirus expressing SerpinB2 and grown subcutaneously in BALB/c mice. SerpinB2 expressing tumours appeared red and were larger than control tumours. Furthermore, SerpinB2 expressing tumours had a ≈2 fold higher density of blood vessels when compared to Tubo and Tubo expressing EGFP. Mice carrying tumours expressing SerpinB2 also showed reduced anti-tumour IgG2 responses. These data suggest that a role for SerpinB2 in regulating angiogenesis and antitumour immunity. In conclusion, this thesis challenges the notion that SerpinB2 regulates Rb, cell cycle, and apoptosis and suggests a potential role for SerpinB2 in tumour angiogenesis and immunity.
20

Human papilloma virus and oral cancers : sexual behaviour as a risk factor

Chiriseri, Edina January 2017 (has links)
AIM & OBJECTIVES: Human papilloma virus (HPV) has been related to cervical infection, however, its part in Head and Neck Squamous Cell Carcinoma (HNSCC) is still debatable and is easy to refute. Suspicion of HPV causation is heightened when carcinomas arise in patients that are young and have never smoked. The present UK based study undertaken at Northampton NHS Trust endeavoured to determine the extent to which HPV is an entity in HNSCC in the UK. Furthermore, the study investigated whether sexual behaviour (as measured by sexual health clinic (SHC) attendance) is linked the acquisition of HPV associated HNSCC in young age groups. HNSCC incidences and sexual trends in the UK were collected from publicly available databases to identify if there were any changes at a national level in sexual behaviours and their influence on HNSCC in young age groups. MATERIALS & METHODS: PCR was used to evaluate the presence of HPV in biopsy samples from of 99 patients diagnosed with HNSCC at Northampton Hospital from 2006 to 2014. Patient demographics on age, sex, smoking, alcohol use and SHC attendance were also collected. All HPV PCR positive biopsies were further genotyped using an ABI 3130xl genetic analyser. Databases in the UK; including GLOBOCAN, NATSAL and PHE were searched for data on HNSCC prevalence, sexual behaviour trends and vaccine uptake. Multinomial regression explored the relationship between HPV positivity and sex, age, smoking, drinking, race and SHC attendance. RESULTS: PCR showed that 25.2% (25/99) of biopsies tested were positive for HPV and were all obtained from white participants. Most specimens (23, 92%) were high-risk (HR) HPV 16 positive with a mean age of 56 for HPV positivity and 72% of the cases 50-60 years old. Smokers were 11% in total (11/99) with most 88.9% participants (88/99) being non-smokers. HPV positivity was strongly linked with non-smoking history (p < 0.001); no alcohol abuse (p < 0.001); male gender (p < 0.001); young age less than 60 years (p < 0.001) and SHC attendance (p < 0.001). A Kruskal-Wallis post hoc test affirmed the impact of age on HPV positivity (p= < 0.05). GLOBOCAN and Cancer Research demonstrated a rising UK HNSCC pattern of over 200% for both sexes from 1975 to 2011. The three NATSAL surveys undertaken in 1990-1991, 1999-2001 and 2010-2012 demonstrated an overall increase in opposite and same sex partners. The UK average of individuals engaging in oral sex was in the younger age groups of between 16 and 54 with at least 70% of males and 63% females of that age engaging in oral sex. Finally, NASTAL 1, 2 and 3 surveys reported 20 vs 15; 25 vs 55; 55 vs 65 of males and females respectively with more than 10 sexual partners to have attended the SHC. The UK immunization take-up was over 90% countrywide. CONCLUSION: Few research studies have been conducted to date on HPV as a cause of HNSCC in the UK. The present research showed 25.2% of HNSCC to be caused by HPV, with the high risk (HR) genotype 16 (the leading cause of cervical cancer) accounting for 92% (23/25) of the cases. These outcomes affirmed the high prevalence of HR-HPV in HNSCC, with a rate of 25.2% similar to those reported previously. Routine HPV testing in those aged below 60 is therefore warranted. Smoking and drinking showed negative correlation; the young age of below 60 and attendance of the SHC for both sexes showed a positive correlation with HPV positive HNSCC. NATSAL data showed increased sexually risky behaviour coupled with attending the SHC in younger ages for both sexes. Increased sexually risky behaviour as shown in NASTAL surveys may be the reason why young age and SHC attendance is positively correlated with HPV HNSCC. The study highlights a conceivable relationship between HPV positive HNSCC in those under 60 years with no smoking history who attended the SHC. Smoking and drinking are known risks for HNSCC in those past 65 years of age; the negative association with HPV HNSCC in the young in the present research revealed smoking and drinking to have reduced association with HPV HNSCC. The reported HR-HPV positive HNSCC in young age groups inform future vaccination strategies and consequently decrease the quantity of HPV HNSCC's.

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