Association of breast cancer with human papillomavirus (HPV) infection in Northeast Brazil: molecular evidence

OBJECTIVE

The aim of this study is to investigate the presence of human papillomavirus DNA and genotypes in breast cancer and normal breast tissue samples obtained from women from the northeast region of Brazil.

METHOD

One hundred three breast cancer samples and 95 normal breast samples, as the non-malignant controls, were studied. DNA extraction was verified by human beta-globin gene amplification, and polymerase chain reaction was conducted based on HPV L1-specific consensus primers MY09/MY11 and GP5+/GP6+, followed by nested multiplex polymerase chain reaction with type-specific primers for the E6/E7 consensus region.

RESULTS

Human papillomavirus DNA was detected in 51 (49.5%) breast carcinoma samples and 15 (15.8%) normal breast samples (p<0.0001). Human papillomavirus genotypes 6 and 11 were identified in 15.2% of all samples.

CONCLUSIONS

The high frequency of human papillomavirus infection in breast cancer samples indicates a potential role of this virus in breast carcinogenesis in the studied participants.

A combinatorial library strategy for the rapid humanization of anticarcinoma BR96 Fab

We have used a combinatorial mutagenesis strategy to humanize BR96, a monoclonal antibody that binds to the Lewis Y class of tumor antigens. This approach allows simultaneous assessment of hundreds of humanized variable regions to identify the molecules that best preserve affinity, thus overcoming the major drawback of current humanization procedures, the requirement to construct and analyze each humanized antibody separately. Murine residues of BR96 were mutated to human if they were solvent-exposed residues that did not participate in the formation of the antigen binding site and were not at the interface of the light and heavy chain. At positions that might be involved in binding to antigen, the choice between the murine and human residue was more difficult. Murine and human alternatives were incorporated into a combinatorial library at positions representing buried residues that might affect the structural integrity of the antigen binding site. By encoding this library of humanized BR96 Fabs in an M13 phage vector, we rapidly identified several candidates with nearly identical antigen binding, within 2-fold, of the chimeric Fab. Additional mutagenesis directed at sites suggested in the literature as potentially important for antigen binding in a similar anti-Lewis Y antibody yielded no further improvements.

Fibrous dysplasia and the temporal bone

The cause of fibrous dysplasia of the bone is obscure. We reviewed the available literature concerning temporal bone involvement and analyzed temporal bone involvement and analyzed the most common aspects of this fascinating disease, adding three cases of our own. A clinical staging is proposed: stage 1, latent; stage 2, symptomatic; and stage 3, complication. Clinical evolution and follow-up are described and treatment is suggested.