miRNAs and
their Applications
Laura Martí Sánchez
Genomics
Advanced Genetic Master
December, 2015
INDEX
 Introduction
 History
 Biogenesis
 Applications:
• Cancer
• Rossetta Genomics kit
Bibliography
Introduction
History
Biogenesis
Applications Bibliography
miRNAs
 non-coding RNA sequences (average length of
22 nucleotides)
 founded in eukaryotes (animals, plants and
viruses)
 Regulation of gene expression thereby
controlling many cellular processes
 Human genome may encode 28645 miRNAs
Todd Smith. May, 2009 FinchTalk. Small
RNAs get smaller
Introduction
History
Biogenesis
Applications Bibliography
First miRNA: lin-4 (1993)
 By efforts of Victor Ambros (1987) and Gary
Ruvkun (1988) in lin-4
 Study of the gene lin-14 en C. Elegans
development
 Negative regulation of gene lin-14
 They showed that this RNA doesn’t encode a
protein
In December 1993, in the same issue of Cell,
Ambros and Ruvkun independently reported
that the small and non-protein coding
transcript lin 4 regulates the gene lin-14
Lin-4 Transcripts and Complementarity between lin-4
and lin-14
Introduction
History
Biogenesis
Applications Bibliography
Processing of miRNA
Transcription
Nuclear
Processing
Nuclear
Export
Cytoplasmatic
Processing
Introduction
History
Biogenesis
Applications Bibliography
miRNA inhibition pathways
Interaction with protein translation
process:
M1: Preventing assembling of the
initiation process
M2: Recluting 60S ribosomic subunit
M3: on the translation process
M6,7: Degradation
Introduction
History
 The development of miRNA
microarrays, RT-PCR platforms
and deep sequencing is a good
advantage for the knowledge of
these RNAs.
 During the past decade, our
knowledge about role of miRNA
in human diseases has grown
exponentially, specially in cancer
Biogenesis
Applications Bibliography
Introduction
History
Biogenesis
Applications Bibliography
miRNAs and Cancer
Utilizing a signature of
altered miRNA expression to
differentiate cancer tissue
from normal tissue
Profiling circular blood or
tumor derived exosomal
miRNAs, surprassing the
invasive procedures to aid
in early detection of
cancers
Use of miRNA based classifier to
identify tissue of origin for
cancers of unknown primaries
miRNAs in
Cancer
Diagnosis
Distinguishing tumor
subtypes using a panel
of miRNAs that show
differential expression
with one cancer type
Study SNPs in the miRNA genes, miRNA binding
sites in the target mRNA genes or in the miRNA
processing/machinery pathway genes to predict
cancer predisposition
Introduction
History
Biogenesis
Applications Bibliography
mi-LungTM Test (Rosetta Genomics)
miRNA
Function
Uses
Hsa-miR-106a
regulates the tumor
suppressor retinoblastoma
High levels in
retinoblastoma
Hsa-miR-125a-5p
Hsa-miR-129-3p
Hsa-miR-205
involved in the invasion
and migration of NSCLC
cells
has not yet been
demonstrated
regulates epithelial to
mesenchymal transition
High levels in
NSCLC
underexpressed in
lung
adenocarcinoma
be used to
distinguish
squamous from
nonsquamous
NSCLC
Hsa-miR-21
Epidermal growth factor
receptor
at higher levels in
NSCLC versus SCLC
Hsa-miR-29b
acts as a tumor suppressor
via the targeting of
methyltransferases
at higher levels in
NSCLC versus SCLC
Hsa-miR-375
regulates cancer growth
up-regulated in lung
cancers with
neuroendocrine
features
Hsa-miR-7
regulate epidermal growth
factor receptor
High levels in NSCLC
451 samples
Nonsquamos
Agilent microarray
(675 probes)
Squamous
cell
Carcinoma
RT-qPCR
Types of
lung
Cancer
Small cell
Carcinoid
Introduction
History
Biogenesis
Applications Bibliography
mi-LungTM Test (Rosetta Genomics)
Introduction
History
Biogenesis
Applications Bibliography
Other tests from Rosetta Genomics
Introduction
History
Biogenesis
Applications Bibliography
• Farazi TA, Spitzer JI, Morozov P, Tuschl T(2011): miRNAs in human cancer. J Pathol
223:102–115
• Gilad S, Lithwick-Yanai G, Barshack I, Benjamin S, Krivitsky I, Edmonston TB, Bibbo
M, Thurm C, Horowitz L, Huang Y, Feinmesser M, Hou JS, St Cyr B,Burnstein I, Gibori
H, Dromi N, Sanden M, Kushnir M, Aharonov R (2012) Classification of
the four main types of lung cancer using a microRNA-based diagnostic assay. J Mol
Diagn 14(5):510-7
• Lee RC, Feinbaum RL, Ambros V. (1993) The C. elegans heterochronic gene lin4 encodes small RNAs with antisense complementarity to lin-14. Cell. 75(5):843-54
• Moura RS, Vaz-Cunha P, Silva-Gonçalves C, Correia-Pinto J. (2015) Characterization
of miRNA processing machinery in the embryonic chick lung. Cell Tissue Res 362(3):569575
• Leonov G, Shah K, Yee D, Timmis J, Sharp TV, Lagos D. (2015) Suppression of AGO2 by
miR-132 as a determinant of miRNA-mediated silencing in human primary endothelial
cells. Int J Biochem Cell Biol. 69:75-84
• Jacek Krol, Inga Loedige & Witold Filipowicz. (2010) The widespread regulation of
microRNA biogenesis, function and decay. Nature Reviews Genetics 11, 597-610
Thanks for your
attention!
Laura Martí Sánchez