The role of miRNA-21 and epithelial mesenchymal transition (EMT) process in colorectal cancer.
OBJECTIVE
The study was conducted to assess the expression levels of epithelial mesenchymal transition (EMT) proteins (E-cadherin, N-cadherin, snail-1 and vimentin) and miRNA-21. In addition, we correlated these data with clinicopathological features in Colorectal cancer.


METHODS
H&E slides from a total of 59 formalin fixed paraffin embedded tissue blocks were examined by a pathologist to demarcate normal and tumour regions. Immunohistochemical analysis of mismatch repair proteins (MLH1, MSH2 and MSH6) and EMT markers (E-cadherin, N-cadherin, snail-1 and vimentin) was performed. The miRNA-21 expression levels were determined using qRT-PCR and the data was analysed using the relative quantification method. The Fisher's exact and Pearson's χ2tests were used to correlate snail-1, E-cadherin, miRNA-21 and clinicopathological data.


RESULTS
Our results showed a statistically significant correlation between high miRNA-21 expression levels and E-cadherin positive cases. There was also an association between high miRNA-21 expression levels and negative snail-1 expression. No significant correlation was seen between miRNA-21 expression levels and clinicopathological features. Moreover, high expression levels of miRNA-21 were significantly associated with the sporadic cases.


CONCLUSIONS
Our data suggest that miRNA-21 in association with E-cadherin and snail-1 does not play a significant role in the development and progression of this disease.
Division of Anatomical Pathology, National Health Laboratory Service, University of Cape Town, Groote Schuur Hospital, Cape Town, Western Cape, South Africa.
Anelisa
A
Jaca
Division of Anatomical Pathology, National Health Laboratory Service, University of Cape Town, Groote Schuur Hospital, Cape Town, Western Cape, South Africa.
Padmini
P
Govender
Division of Anatomical Pathology, National Health Laboratory Service, University of Cape Town, Groote Schuur Hospital, Cape Town, Western Cape, South Africa.
Michael
http://orcid.org/0000-0002-3917-3895
M
Locketz
Division of Anatomical Pathology, National Health Laboratory Service, University of Cape Town, Groote Schuur Hospital, Cape Town, Western Cape, South Africa.
Richard
R
Naidoo
D000328:Adult; D000368:Aged; D015703:Antigens, CD; D014408:Biomarkers, Tumor / Q000032:analysis*; D015820:Cadherins / Q000032:analysis / Q000096:biosynthesis; D015179:Colorectal Neoplasms / Q000235:genetics / Q000473:pathology*; D058750:Epithelial-Mesenchymal Transition / Q000235:genetics*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D035683:MicroRNAs / Q000032:analysis / Q000096:biosynthesis*; D008875:Middle Aged; D000071250:Snail Family Transcription Factors / Q000032:analysis / Q000096:biosynthesis
D015703:Antigens, CD; D014408:Biomarkers, Tumor; C513384:CDH1 protein, human; D015820:Cadherins; C524940:MIRN21 microRNA, human; D035683:MicroRNAs; C000604407:SNAI1 protein, human; D000071250:Snail Family Transcription Factors
CANCER STEM CELLS; COLORECTAL CANCER; IMMUNOHISTOCHEMISTRY; ONCOGENES