IL6 and retinoblastoma: Mechanically, immune cell infiltration and microenvironment interaction with RB is likely observed in all types of RB, where immune cells markers present in orthotopic transplantation models of RB in mice and immunostimulatory factors such as IL-12p70, TNF-α, IL-6, IL-1β and IL-8 are secreted by RB cells to accommodate immune cells in the microenvironment (Lee et al., 2013; Ma et al., 2014).