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Published on: July 23, 2010
Human papillomavirus types 16 E6 and E7 contribute differently to carcinogenesis
1McArdle Laboratory for Cancer Research, University of Wisconsin Medical School, 1400 University Avenue, Madison, Wisconsin 53706, USA.
Virology
|February 9, 2000
Summary
High-risk human papillomaviruses (HPVs) oncogenes E6 and E7 play distinct roles in cancer development. E7 promotes benign tumor formation, while E6 drives malignant progression, cooperating to cause tumors.
Area of Science:
- Oncology
- Virology
- Molecular Biology
Background:
- High-risk human papillomaviruses (HPVs) are linked to cervical cancer.
- The viral genes E6 and E7 are frequently expressed in HPV-associated cancers.
- Previous studies showed HPV-16 E6 or E7 transgenic mice develop skin tumors.
Purpose of the Study:
- To investigate the distinct roles of E6 and E7 in carcinogenesis.
- To determine the specific stages of carcinogenesis where E6 and E7 act.
- To assess the synergistic effects of E6/E7 with chemical carcinogens.
Main Methods:
- Utilized K14E6 and K14E7 transgenic mouse models.
- Applied chemical carcinogens to mouse skin to induce distinct carcinogenesis stages.
- Analyzed tumor formation and progression in response to E6 and E7 expression.
Main Results:
- Both E6 and E7 synergize with chemical carcinogens to promote tumor formation.
- E7 primarily acts at the promotion stage, leading to benign tumors.
- E6 acts weakly at promotion but strongly at the progression stage, driving malignant conversion.
Conclusions:
- E6 and E7 have distinct roles in carcinogenesis: E7 promotes benign tumor formation, and E6 accelerates malignant progression.
- E6 and E7 cooperate to induce tumor formation, highlighting their combined oncogenic potential.
- These findings provide direct evidence for the differential contributions of E6 and E7 to cancer development.
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