ASSOCIAÇÃO DE HPV EM CARCINOMAS ESPINOCELULARES DE PÊNIS: UMA META-ANÁLISE

Abstract

Cancer has been a major public health problem both in developed and developing countries . Each year, cancer is responsible for more than six million deaths, imposing a population burden that claims about 12% of all causes of that worldwide. Under a genetic perspective, there are two major classes of gene that hold an important role on cancer development: the proto-oncogenes and the tumor suppress genes. Mutations in these genes are the underlying cause of uncontrolled cell proliferation. Under the spectrum of male urological tumors, penile carcinoma is the one that most resembles cervical carcinoma in women. Epidemiological studies have frequently implicated HPV genome as a potential initiator factor for carcinomas of different anatomical sites. HPV role in cancer induction is well documented for cervical carcinomas and a significant association has been found in up to 99,7% of all cases worldwide. The occurrence of HPV in both male and female genital areas has increased the scientific interest around the potential association of HPV genome and penile carcinomas. The HPV genome is mode of one copy of the double-stranded circular DNA molecule, organized in three distinct regions: a Long Control Region (LCR), an Early (E) and a Late (L) protein coding regions. Following viral insertion in a cell genome, the viral LCR becomes the target of an intracellular regulatory mechanism. When infected cells lose this control mechanism, tumor progression towards malignancy and increased viral gene expression occur. Penile cancer is a rare disease, however by far the most common type is the squamous cell carcinoma which is found in about 95% of the penile malignancies. As any other Sexually Transmitted Disease, men are the major link in the chain of infection of HPV. The Polimerase Chain Reactions is the most sensitive procedure to detect and genotype HPV DNA in human biological samples. The current study is a meta-analysis which comprised the result of several studies that using PCR detected and genotyped HPV genome in association with penile cancers. Herein we report on the results of 39 research articles published from 1989 to 2009. We found the published data had large heterogeneity, tending to significance when combined within the 95% confidence interval. The DermonSaimonian-Laird analysis indicated significance between HPV infection and penile cancer development.