Abstract: The invention relates to bacterial promoter elements which constitute or which are comprised in promoter regions and which confer tumour specificity to the promoter region activity, resulting in transcription of a transgene, which can be a heterologous or a homologous gene, which transgene is functionally arranged downstream of the promoter region at presence of a host bacterium in tumour tissue, while essentially conferring inactivity of the promoter region and no transcription at presence of the host bacterium in non-tumour tissue. Accordingly, the invention relates to bacterial promoter regions containing these tumour specific promoter elements.

Abstract: The present invention provides pharmaceutical compositions for use in tumor therapy as well as a medical treatment in tumor therapy. The compositions comprise a leukocyte diminishing and/or leukocyte inactivating agent for use in bacterial tumor therapy in combination. Preferably, the leukocyte inactivating or diminishing agents are expressed by the bacteria used for the production of a pharmaceutical composition for bacterial tumor therapy.