MRC1 and neoplasm: In the 4T1 tumor model poly(styrene-co-maleic anhydride) (PSMA) nanoparticles conjugated with polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene, PPV] were able to attenuate tumor growth and modulate TME by upregulation of M1 macrophage markers (CD86, CD80, iNOS, TNF-alpha) and downregulation of M2-like markers (CD206, CD163) in the TME (219).