A Genetic Screen Implicates miRNA-372 and miRNA-373 As Oncogenes in Testicular Germ Cell Tumors

Abstract

Endogenous small RNAs (miRNAs) regulate gene expression by mechanisms conserved across metazoans. While the number of verified human miRNAs is still expanding, only few have been functionally annotated. To perform genetic screens for novel functions of miRNAs, we developed a library of vectors expressing the majority of cloned human miRNAs and created corresponding DNA barcode arrays. In a screen for miRNAs that cooperate with oncogenes in cellular transformation, we identified miR-372 and miR-373, each permitting proliferation and tumorigenesis of primary human cells that harbor both oncogenic RAS and active wild-type p53. These miRNAs neutralize p53-mediated CDK inhibition, possibly through direct inhibition of the expression of the tumor-suppressor LATS2. We provide evidence that these miRNAs are potential novel oncogenes participating in the development of human testicular germ cell tumors by numbing the p53 pathway, thus allowing tumorigenic growth in the presence of wild-type p53.

CBX7 and miR‐9 are part of an autoregulatory loop controlling p16INK4a

“…Plasmids encoding for different microRNAs and its corresponding control were obtained from the miR‐Vec library (Voorhoeve et al ., 2006). The CBX7 reporter plasmid has been described before (O'Loghlen et al ., 2012) and was used to derive the CBX7 3′UTR 9.1/2 reporter by Gibson assembly.…”

Loss of p21Sdi1 expression in senescent cells after DNA damage accompanied with increase of miR-93 expression and reduced p53 interaction with p21Sdi1 gene promoter

“…Indeed, multiple microRNAs in miR-106 family and related miRNAs rescue Ras-induced senescence and induce colony formation in soft agar in HMECs via downregulation of p21 by miR-106/302 [28]. They are associated with progression of variable tumors; miR-106a and miR-106b in gastric adenocarcinoma [29], miR-17-5p and miR-372 in squamous cell carcinoma [30], miR-372 and miR-373 in testicular germ cell tumors [10], and miR-373 with miR-520c in the metastatic tumors [31]. Moreover, inactivation of p21 and p16 INK4a facilitates immortalization and anchorage independent growth of mouse fibroblasts [11].…”

“…p21 is involved in the Ras G12V -induced senescence in different human cells; inhibition of p21 expression results in Ras G12V -resistant growth in BJ foreskin fibroblasts [10] and LF1 human lung fibroblasts [11]. Treatment of various human cells with low dose doxorubicin (200 ng/ml) also induces growth arrest with high expressions of p53 and p21 [12].…”

MiRNA expression analysis during normal zebrafish development and following inhibition of the Hedgehog and Notch signaling pathways

“…Direct cloning strategies and bioinformatic prediction based on the presence of conserved hairpin structures and sequences have suggested that animal genomes encode hundreds, perhaps thousands, of microRNAs (Lagos-Quintana et al, 2001;Lau et al, 2001;Lee and Ambros, 2001;Lai et al, 2003;Lim et al, 2003a;Lim et al, 2003b;Kim and Nam, 2006). These small RNAs regulate early development, cell specification, differentiation, and proliferation (Lee et al, 1993;Pasquinelli et al, 2000;Reinhart et al, 2000;Ambros, 2003;Bartel, 2004;Griffiths-Jones, 2004;Hobert, 2004;Du and Zamore, 2005;Hatfield et al, 2005;Morris and McManus, 2005;O'Donnell et al, 2005;Carthew, 2006;Esquela-Kerscher and Slack, 2006;Naguibneva et al, 2006;Plasterk, 2006;Slack and Weidhaas, 2006;Voorhoeve et al, 2006).…”