The JAK2/STAT3 signaling pathway is required for growth of CD44+CD24– stem cell–like breast cancer cells in human tumors

Intratumor heterogeneity is a major clinical problem because tumor cell subtypes display variable sensitivity to therapeutics and may play different roles in progression. We previously characterized 2 cell populations in human breast tumors with distinct properties: CD44+CD24- cells that have stem cell-like characteristics, and CD44-CD24+ cells that resemble more differentiated breast cancer cells. Here we identified 15 genes required for cell growth or proliferation in CD44+CD24- human breast cancer cells in a large-scale loss-of-function screen and found that inhibition of several of these (IL6, PTGIS, HAS1, CXCL3, and PFKFB3) reduced Stat3 activation. We found that the IL-6/JAK2/Stat3 pathway was…

• AC
  American Cancer Society
• SG
  Susan G. Komen for the Cure
• BC
  Breast Cancer Research Foundation
• DC
  Dana-Farber Cancer Institute
• FC
  Fundación Cellex
• TB
  Terri Brodeur Breast Cancer Foundation
• NI
  Novartis Institutes for BioMedical Research
• NC
  National Cancer Institute