HIF1A and neoplasm: Therefore, regulating Bclaf1 can directly enhance HIF-1α stability and promote tumour progression.182 These combined metabolic alterations generate the energy of CTL, recruitment of Tregs, and MDSCs, the polarization of immune-suppressive M2 macrophages, and immunotherapy resistance.183 The adenosine signalling and kynurenine metabolites are employed by both MDSCs and tumour cells.