Delving deeper into inhibitory immune checkpoint molecules, publications for T cell immunoreceptor with Ig and ITIM domains (TIGIT) and B7-H3 38 grew on an average 1.5X over the last three years (Fig. ) and might be emerging rapidly as compared to the rest of the checkpoint molecules (Fig. ). PD-1 and programmed cell death ligand 1 (PD-L1) appear to be growing at a modest pace while others such as indoleamine 2,3 -dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO), enzymes vital for tryptophan degradation, appear to be growing slowly (Fig. ). Hematopoietic progenitor kinase (HPK) and TANK-binding kinase 1 (TBK1) among other kinases are emerging as the fast-growing concepts with publications appearing to have tripled or nearly tripled over the past three years (Figs. and). Other members of the kinase family such as janus kinase (JAK) and pyruvate kinase M2 (PKM2) are growing at a modest pace (Figs. and).