IRS1 and cancer: Other reported targets of the miR-23a, whose suppression facilitated the cancer cell migration and invasion, include XIAP [86], metastasis suppressor protein 1 (MTSS1) [22,49], insulin receptor substrate 1 (IRS-1) [41], Sprouty homolog 2 (SPRY2) [31,87], and PTEN [85].