Human Papillomavirus (HPV)

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					Human Papillomavirus

 Nazanin Sharifi, Greg Richart
Human Papillomavirus
 What is HPV ?
 Taxonomy
 Symptoms
 The HPV genome
 HPV and Cancer
 Diagnosis
 Epidemiology
 Risk factors
 Treatment/Current Research
 Family: Papillomaviridae
 Genus:
    Alphapapillomavirus
       Approximately 70 species (6, 11,16,18,)

    Betapapillomavirus
       Approximately 20 species

    Gammapapillomavirus
       7 species

    Mupapillomavirus
       2 species

    Nupapillomavirus
       1 species
   What is HPV?
 HPV is a double-stranded DNA virus that is a sexually transmitted
  disease (STD)
 Over 100 different strains, more than 30 sexually transmittable
 Targets:
    Skin and mucosal membranes
        Oral mucosa

        Esophagus

        Larynx (voice box)

        Trachea (airway)

        Conjunctiva of the eye

        Cervix primarily affected, but also vagina, penis, etc. \

        Hand, Feet,

 Strains 16 and 18 considered “High Risk,” cancer-causing types
 Strains 6 and 11 considered “High Risk” and responsible for
  genital warts
Symptoms of Infection!
 Typically, no signs of infection

 Infections usually transient, but can be carried
  dormant for days/months/years

 Genital warts may develop weeks or months
  after initial infection

 Genital cancer can result from infection
The HPV Genome
HPV and Cancer
 Strains 6, 11, 16, and 18 responsible for 70% of
  cervical cancer and 90% genital warts

 Strain 16 prevalent in penile carcinoma

 Viral genes E6 and E7 are oncogenes
      E6 subjugates cellular p53 protein
      E7 subjugates cellular pRB protein
      p53 and pRB are critical for regulation of
       cancerous cells
Diagnostic tests
                                     Pap test should be done
                                       approx. 3 years after the onset
                                       of sexual activity or earlier

                                     Around 55 million Pap tests
                                       are performed each year

                                     3.5 million tests show

                                     Pap test should be done once
                                       every three years (depending
                                       on the test result)
The area where the two types of
cells reside is where the sample     To get a free or low-cost Pap
tissue is taken from and sent out      test, please call 1800-4-
to have PAP test done
                                     As of now, there are no
                                       diagnostic tests to be done for
 HPV is the most common STD in the US

 20 million Americans infected (15% population)
      Over half infected 15-24 years old
      Approx. 30% infected with multiple strains

 6.2 million new infections each year

 By age of 50, at least 80% of women will have been infected

 In 2006, >9,700 women will be diagnosed with cervical
  cancer and 3,700 will die
   Risk Factors and Prevention
 No “cure” for HPV – prevention most effective
      Regular gynecological exams
      Frequent, proper screening for cervical cancer
         Pap Test (Three years after the onset of sexual activity)

             Colonoscopy
      Abstinence
      Use of condoms

 Risk Factors:
      “High risk” sexual activity
      Smoking
      Co-infections
Treatment – HPV Vaccine
 “Gardasil” vaccine Approved
    by FDA on June 8, 2006

 Protects against HPV strains 6,
    11, 16, and 18

 Made from non-infectious virus-
    like particles (VLPs)

  Advisory Committee on
  Immunization Practices
  recommends use of vaccine for
  females 9-26 years of age
 Cryosurgery - Freezing off the
                                    Virus-like particles assembled
                                    from L1 protein of HPV16
Treatment – Current Research
 RNA Interference
     Targets high-risk HPV strain 16
     Inhibits E6 oncogene expression
     Great potential, but very new (more testing)

 Blockage of estrogen receptors
     Estrogen may stimulate HPV oncogene
     Also very new
   “Doorbar Group: Human Papillomavirus.” National Institute for Medical
            Research. Online Resource. Accessed December 10, 2006. Available at
   Human Papillomavirus: HPV Information for Clinicians. Centers for Disease Control
            and Prevention. Prepared November 2006. PDF available at
   “Human Papillomavirus (HPV) Infection.” Centers for Disease Control and
            Prevention. Online Resource. Accessed December 10, 2006. Available at
   Au WW, Abdou-Salama S, Al-Hendy A. Inhibition of Growth of Cervical Cancer Cells
            Using a Dominant Negative Estrogen Receptor Gene. Gynecologic Oncology.
            Nov. 28, 2006.
   Niu XY, Peng ZL, Duan WQ, Wang H, Wang P. Inhibition of HPV 16 E6 oncogene
            expression by RNA interference in vitro and in vivo. International Journal of
            Gynecological Cancer. March-April, 2006.
   Higgins GD, Davy M, Roder D, Uzelin DM, Phillips GE, Burrell CJ. Increased
            Age and M ortality Associated with Cervical Carcinomas Negative for
            Human Papillomavirus RNA. The Lancet. Oct. 12, 1991.
   Ortiz, Yarissa. High HPV Concentrations Combined with Cigarette Smoking
            Significantly Raise Risks of Later Cervical Cancer. American Association for
            Cancer Research. November 17, 2006.
   Pics Taken From

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