The present invention relates to an attenuated strain of Salmonella comprising at least one copy of a DNA molecule comprising an expression cassette encoding a VEGF receptor protein, for use in the treatment of cancer, wherein the treatment further comprises the administration of at least one further anti-cancer agent. The present invention further relates to a pharmaceutical composition comprising an attenuated strain of Salmonella comprising at least one copy of a DNA molecule comprising an expression cassette encoding a VEGF receptor protein, wherein the pharmaceutical composition further comprises at least one further attenuated strain of Salmonella comprising at least one copy of a further DNA molecule comprising a further expression cassette encoding a tumor antigen or a tumor stroma antigen.