MiR-21 plays an important role in tumor formation and development , and it has been shown to be a key regulator of oncogenic processes and it may be a useful biomarker for breast cancer .
Estimation of miR-21 gene expression levels in both fresh tissues and serum of same breast cancer patients before and after operation by using stem-loop followed by Taq-Man Real Time PCR (RT-PCR) technique and correlate the miR-21 gene expression with stages of breast cancer and lymph node involvement.
MATERIAL AND METHODS:
Stem-loop RT-PCR was performed to identify the level of miR-21 gene expression in both fresh tissues and serum of same breast cancer patients before and after operation . The expression levels of miR-21 relative to mRNA of GAPDH were determined by using the livak method.
Mean fold change of miR-21 was significantly higher in breast cancer than that of paracancerous tissues . Before operation ,the mean fold change of serum miR-21gene expression significantly statistical difference from healthy control ,the mean fold change of miR-21 in advance stage( III,IV) was significantly higher than that early stage (I,II) and mean fold change of miR‑21 in positive lymph node was higher than that of negative lymph node . After operation the mean fold change of serum miR-21gene expression was significantly higher than healthy control .A statistically significant difference was noted between advance stage with lymph node involvement and early stage with negative lymph node involvement .In contrast , the mean fold change of serum miR-21 was significantly lower from that before operation .
Circulating miR-21 before and after operation can serve as a good biomarker for breast cancer detection and progression .