REGULATION OF ONCOGENIC ACTIVITIES OF HIGH-RISK HPV ONCOGENES BY E6 GENE OF BENIGN HPVS

2.50
Hdl Handle:
http://hdl.handle.net/10755/211525
Type:
Research Study
Title:
REGULATION OF ONCOGENIC ACTIVITIES OF HIGH-RISK HPV ONCOGENES BY E6 GENE OF BENIGN HPVS
Abstract:
Background: The Human Papillomavirus (HPV) epidemic remains a public health burden.  Although the majority of HPV infections are asymptomatic or self-limited, acquisition of alpha or high risk (HR) HPV can result in neoplastic changes of lower genital and non-genital sites.  Expression of HPV16 E7 & E6 and HPV5 E7 & E6 oncoproteins in primary, human epithelial cells leads to genomic instability.  Molecular processes involved in genomic destabilization are essential for the development of cancer.  HPV-related cancers appear to maintain and express HPV viral oncogenes for years or even decades.  Even in advanced stages of disease, strategies targeting gene expression for the prevention of viral oncogene expression can stop the growth or survival of cancer cells.  It is possible that HPV targeted strategies, such as pharmacologic molecules that interfere with the expression or action of viral proteins, or that elicit a cytolytic immune response to cells expressing oncoproteins, may prevent primary oncogenesis or further progression of a tumor or cancer.  Aims: The overall purpose is to determine whether benign HPVs, which are present along with HR HPVs, suppress the oncogenic activities of HR HPVs.  Aim 1:  To determine the transformation suppression activity of HPV 21 E6 protein on the transforming activity of HPV 16 E7 and E6.  Aim 2:  To determine whether the E6 protein of benign HPVs antagonize the transforming activity of the HR HPVs, thereby leading to tumor suppression.  Methods:  Measuring the transforming activities of E7 and E6 include:  a) large-scale preparation of plasmid DNA, b) transfection of established rodent cells, c) extraction and culture of primary epithelial cells, d) transfection of epithelial cells, e) selection of colonies and generation of transformed cell lines, and f) verification of continued oncoproteins expression.  Established colonies will be enumerated and used to determine inhibition of oncogenic activity.  The activity of low-risk HPV 21 E6 protein on the transforming activity of HPV 16 E7 and E6 as well as whether the E6 protein found in low-risk HPVs antagonizes the transforming activity of HR HPVs will be analyzed.  Results:  The proliferating HPV16 E7 & E6 and HPV5 E7 & E6 (MT L21S) were serially propagated in medium for >7 passages without any evidence of cellular senescence.  HPV16 E7 & E6, beginning with Passage 5, grew rapidly and was primarily made up of fibroblasts.  HPV5 E7 & E6 (MT L21S), beginning with Passage 5, grew rapidly and consisted of epithelial cells.  This rapid growth was consistent with an unlimited proliferative potential or immortalization.  In contrast, HPV5 E7 & E6 (WT), beginning with Passage 5, grew slowly.  The cells appeared large and many senescent.  Beginning with Passage 1, pCDH-MCS1-Ef1-Puro Vector had not divided and cellular senescence persisted.  Implications: These laboratory experiments may lead to important insights into strategies that can be used to inhibit the oncogenic activity of HR HPVs.  One such strategy includes the development of pharmacologic molecules that mimic the effect of HPV 21 E6 (a suppressor of oncogenic transformation).
Keywords:
Human Papillomavirus; HPV
Repository Posting Date:
20-Feb-2012
Date of Publication:
20-Feb-2012
Other Identifiers:
5362
Sponsors:
Western Institute of Nursing

Full metadata record

DC FieldValue Language
dc.typeResearch Studyen_GB
dc.titleREGULATION OF ONCOGENIC ACTIVITIES OF HIGH-RISK HPV ONCOGENES BY E6 GENE OF BENIGN HPVSen_GB
dc.identifier.urihttp://hdl.handle.net/10755/211525-
dc.description.abstractBackground: The Human Papillomavirus (HPV) epidemic remains a public health burden.  Although the majority of HPV infections are asymptomatic or self-limited, acquisition of alpha or high risk (HR) HPV can result in neoplastic changes of lower genital and non-genital sites.  Expression of HPV16 E7 & E6 and HPV5 E7 & E6 oncoproteins in primary, human epithelial cells leads to genomic instability.  Molecular processes involved in genomic destabilization are essential for the development of cancer.  HPV-related cancers appear to maintain and express HPV viral oncogenes for years or even decades.  Even in advanced stages of disease, strategies targeting gene expression for the prevention of viral oncogene expression can stop the growth or survival of cancer cells.  It is possible that HPV targeted strategies, such as pharmacologic molecules that interfere with the expression or action of viral proteins, or that elicit a cytolytic immune response to cells expressing oncoproteins, may prevent primary oncogenesis or further progression of a tumor or cancer.  Aims: The overall purpose is to determine whether benign HPVs, which are present along with HR HPVs, suppress the oncogenic activities of HR HPVs.  Aim 1:  To determine the transformation suppression activity of HPV 21 E6 protein on the transforming activity of HPV 16 E7 and E6.  Aim 2:  To determine whether the E6 protein of benign HPVs antagonize the transforming activity of the HR HPVs, thereby leading to tumor suppression.  Methods:  Measuring the transforming activities of E7 and E6 include:  a) large-scale preparation of plasmid DNA, b) transfection of established rodent cells, c) extraction and culture of primary epithelial cells, d) transfection of epithelial cells, e) selection of colonies and generation of transformed cell lines, and f) verification of continued oncoproteins expression.  Established colonies will be enumerated and used to determine inhibition of oncogenic activity.  The activity of low-risk HPV 21 E6 protein on the transforming activity of HPV 16 E7 and E6 as well as whether the E6 protein found in low-risk HPVs antagonizes the transforming activity of HR HPVs will be analyzed.  Results:  The proliferating HPV16 E7 & E6 and HPV5 E7 & E6 (MT L21S) were serially propagated in medium for >7 passages without any evidence of cellular senescence.  HPV16 E7 & E6, beginning with Passage 5, grew rapidly and was primarily made up of fibroblasts.  HPV5 E7 & E6 (MT L21S), beginning with Passage 5, grew rapidly and consisted of epithelial cells.  This rapid growth was consistent with an unlimited proliferative potential or immortalization.  In contrast, HPV5 E7 & E6 (WT), beginning with Passage 5, grew slowly.  The cells appeared large and many senescent.  Beginning with Passage 1, pCDH-MCS1-Ef1-Puro Vector had not divided and cellular senescence persisted.  Implications: These laboratory experiments may lead to important insights into strategies that can be used to inhibit the oncogenic activity of HR HPVs.  One such strategy includes the development of pharmacologic molecules that mimic the effect of HPV 21 E6 (a suppressor of oncogenic transformation).en_GB
dc.subjectHuman Papillomavirusen_GB
dc.subjectHPVen_GB
dc.date.available2012-02-20T12:00:14Z-
dc.date.issued2012-02-20T12:00:14Z-
dc.date.accessioned2012-02-20T12:00:14Z-
dc.description.sponsorshipWestern Institute of Nursingen_GB
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