In Clinical Cancer Research this week, researchers in Germany say cancer stem cells could be used as targets and biomarkers for radiotherapy treatments. Cancer stem cells appear to have a higher resistance to radiotherapy than non-cancer stem cells, the authors write. If this is so, it could be important for the development of predictive biomarkers for radiocurability of a given tumor. Cancer stem cells could also be used to develop drugs that inhibit stem-cell–related signal transduction pathways, the team says. "We need to preclinically test such drugs as combined-modality therapies in combination with radiotherapy to evaluate their curative potential, and optimize them by increasing their specificity to CSCs over normal tissue stem cells to avoid increased radiation toxicity," the researchers add.
Also in Clinical Cancer Research this week, researchers in China report that tumor-associated macrophages promote angiogenesis and melanoma growth. High numbers of tumor-associated macrophages in the tumor microenvironment can usually mean poor prognosis for melanoma patients. For the study, the team established in vitro and in vivo models to investigate TAMs in melanoma, and found that they enhance endothelial cell migration and tubule formation, and also increase tumor growth.
And finally in Clinical Cancer Research this week, an international team of researchers explores the gene expression differences between colon tumors and rectal tumors, both of which are found in colorectal cancer. The team analyzed data from 460 colon tumors and 100 rectum tumors and found only small differences at the gene expression level between tumors arising in the proximal colon, distal colon, or rectum. "Microsatellite stable colorectal cancers do not show major transcriptomic differences for tumors arising in the colon or rectum," the authors write. "The small but consistent differences observed are largely driven by the HOX genes."