The invention described and claimed in this patent application provides for novel hybrid vectors which may be used for cell transformation, either in vivo or in vitro. The hybrid vectors have an adenoviral backbone with retroviral long terminal repeats (LTRs). Such vectors are capable of transforming dividing or non-dividing cells and integrate stably into the chromosome providing a means of efficient, reliable, long-term gene expression. The vector was packaged as a recombinant adenovirus and delivered to the target cell. Unlike other chimeric or hybrid vector systems, only a single vector is required to deliver a transgene of interest, and retroviral structural proteins are not required.