STAT3 inhibition might also promote the differentiation of MDSCs and induce immature myeloid cells toward a more mature, HLA-DR positive status, as shown for the circulating M-MDSCs of advanced lung carcinoma patients treated with Cucurbitacin B (CuB), a selective inhibitor of the JAK2/STAT3 pathway [29,30]. Here, STAT3 is linked to lung carcinoma.