Abstract:
Solid tumors display complex biology and most therapies including
chemotherapy cannot prevent therapy resistance and relapse. Most therapeutics target cancer
cells, but recent data suggest the presence of cancer stem cells as cells with self-renewal and
tumorigenic abilities. Cancer stem cell markers have been suggested to have prognostic value
and can be targeted during cancer treatment and in resistant disease. CSCs have been
postulated to play significant contextual roles in tumor initiation, progression, therapy
resistance and metastasis. CSCs have thus been targeted by new generation cancer drugs. The
transcriptional expression of several CSC markers in different cancers was evaluated by
searching publicly available The Cancer Genome Atlas (TCGA) and Gene Expression
Profiling Interactive Analysis (GEPIA) databases. We report here new findings on expression
and prognostic significance of CSC markers in several cancers by examining the expression
of CSCs markers in tumor tissues versus the adjacent normal tissues. We found that CSC
markers were mostly highly expressed various tumors such as colon, lung, pancreatic and
esophageal cancers. No CSC marker is expressed in the same pattern in all cancers and
individual CSC marker expression was not linked to patient survival. This analysis calls for
continued research on CSCs and clinical evaluation of the CSC markers in relation to
prognosis of cancers in large population samples. Novel cancer drugs ought to target CSCs,
cancer cells and tumor microenvironment variations.
