TNF and cancer: The tropism of macrophages or their predecessor monocytes for cancer-related cytokines (e. g., CSF-1, VEGF, TNF, IL-1, IL-5, etc.)and chemokines (e. g., CCL-5, 7, 8, 12, etc.)based on the ability of macrophages or their predecessor monocytes to cross physiological barriers make them another ideal vehicle for oncology drug delivery.76