RB1 and breast cancer: Retinoblastoma (RB) gene also frequently mutated in BC, and the restoration of wild‐type RB expression is growth‐inhibitory to BC cells.77 CG‐0700, a recombinant adenovirus specifically targeting Rb pathway, could replicate selectively in tumor cells and produce granulocyte macrophage‐colony stimulating factor (GM‐CSF).78, 79 GM‐CSF could recruit and mature myeloid cells and enhance the local antitumor activity.