The present invention relates to a recombinant virus of the family Paramyxoviridae, comprising at least one expressible polynucleotide encoding a secreted activator of the immune response, to a polynucleotide encoding the same, and to a kit comprising the same. Moreover, the present invention relates to a method for treating cancer in a subject afflicted with cancer, comprising contacting said subject with a recombinant virus of the family Paramyxoviridae of the invention, and thereby, treating cancer in a subject afflicted with cancer.