Preneoplastic lesions, detectable by breast cancer screening, are made up of altered cells that are not themselves cancerous but indicate an increased likelihood that a benign or cancerous tumor may subsequently form.

Writing in the Journal of Clinical Investigation, Federica Cavallo and colleagues from the University of Turin, Italy, evaluated vaccine strategies for treating neoplastic lesions. The authors designed a combined approach consisting of a primary vaccination with plasmids encoding portions of the oncogenic protein rp185neu and a booster vaccination one week later with cells expressing this protein and also engineered to release IFN-gamma.

Of mice that received the combined vaccine, 48% remained tumor free for the duration of the study, a significant improvement over untreated mice and mice receiving only the primary vaccine.

The researchers say that both an analysis of the lesions and microarray analysis of gene expression revealed that the immune reaction halted carcinogenesis and the neoplastic lesions reverted to an early stage.

This study highlights the potential of a combined approach to vaccination for the prevention and suppression of neoplastic lesions, they write.

SOURCE:
Journal of Clinical Investigation, March 1, 2004