J Cancer Res Clin Oncol. 2016 Jul;142(7):1487-98. doi: 10.1007/s00432-016-2171-y. Epub 2016 Apr 27.
Clonal heterogeneity in osteogenic potential of lung cancer-associated fibroblasts: promotional effect of osteogenic progenitor cells on cancer cell migration.
BACKGROUND: Cancer-associated fibroblasts (CAFs) consist of heterogeneous cell population in terms of their differentiation potential. The functional differences in tumor progression between CAFs with mesenchymal stem/progenitor cells (MSCs/MPCs) characteristics and CAFs without MSCs/MPCs characteristics are not clarified.
METHODS: CAFs and vascular adventitial fibroblasts (VAFs, which contain MSCs/MPCs) were isolated from nine primary lung cancers and were cultured in osteogenic or adipogenic medium to assess their multi-lineage differentiation. Next, we established nine single-cell-derived clones from the primary culture of CAFs and examined their differentiation potential. The effects of each single-cell-derived clone on the proliferation and migration of lung adenocarcinoma cell line, A549, were analyzed.
RESULTS: The nine samples of VAFs and CAFs showed various degrees of osteogenic differentiation. Although the VAFs displayed the ability to undergo adipogenic differentiation, all cases of the CAFs did not. CAFs clones presented varying degrees of osteogenic differentiation. Four clones displayed comparable levels of osteogenic potential with that of the VAFs, and two clones were completely negative. As compared to the CAFs clones that possessed lower osteogenic potential, CAFs clones with higher osteogenic potential did not confer proliferative activity in A549 cells. On the contrary, these clones significantly promoted the migration of A549 cells as compared to the clones with lower osteogenic potential.
CONCLUSION: Our studies clearly indicate that CAFs derived from lung cancer are heterogeneous population that consists of cells with varying osteogenic potentials and that CAFs with higher osteogenic potential have a greater tumor-promoting function through the enhancement of cancer cell migration.