IL6 and cancer: On the other hand, copy number gain of the T-cell malignancy 1 (MCT1) gene has been found to promote EMP, cancer stemness and M2 macrophage polarization in triple-negative breast cancer (TNBC) by direct suppression of miR-34a and consequent IL-6/IL-6R increased signalling, reinforcing the reciprocal signalling between IL-6 and miR-34 [125].