Expression Levels of the microRNA Processing Enzymes Drosha and Dicer in Epithelial Skin Cancer

Abstract

We observed dysregulation of Drosha and Dicer expression in epithelial tumors when compared to healthy control samples. Therefore, we favor the hypothesis that miRNAs are involved in the carcinogenesis of epithelial skin cancer.

From keratinocyte to cancer: the pathogenesis and modeling of cutaneous squamous cell carcinoma

“…Consistent with a likely role of miRNA in cSCC development, SCC tumor tissue is associated with increased activity of Drosha, a key element required for miRNA maturation (84). Further, the miRNA profile in epidermis is altered in SCC, with both tumors and UVA-exposed keratinocytes displaying elevated levels of miR21 (85).…”

Downregulation of Dicer, a component of the microRNA machinery, in bladder cancer

“…However, it is unclear whether the observed upregulation or downregulation of miRNA expression simply reflects malignant degeneration of the tumor or directly causes tumor initiation and progression. Changes in the stoichiometry of miRNA machinery components are thought to explain abnormal miRNA profiles in different cancer types (31). Therefore, it is possible that the downregulation of Dicer is a prerequisite to the abnormal miRNA observed in cancers (15).…”

Recurrent SomaticDICER1Mutations in Nonepithelial Ovarian Cancers

“…12,13 The expression levels of Dicer have global effects on the biogenesis of miRNA, and reduced expression correlates with a poor outcome in many cancers. 7,[14][15][16][17][18] In mouse models of cancer, the loss of a single Dicer1 allele (haploinsufficiency) reduced the time to tumor onset 19 or survival time, 20 as compared with control animals. Experimental data support the hypothesis that the pathogenicity of aberrations in Dicer function is dependent on the cellular context and that the activation or inhibition of pathways for tissue-specific development and differentiation are at least partially controlled by specific miRNAs or miRNA families.…”