Genetic Heterogeneity of Breast Cancer Metastasis May Be Related to miR-21 Regulation of TIMP-3 in Translation

Table 4

Sample	Group	Mean ± SD	𝐹	𝑃
Tissue miR-21	High	9.34 ± 1.87	70.91	0.000
	Low	4.65 ± 1.44
	Normal	0.00 ± 2.59
Serum miR-21	High	10.91 ± 1.82	85.38	0.000
	Low	7.25 ± 1.49
	Normal	0.00 ± 2.94
TIMP-3 mRNA	High	−6.90 ± 2.09	35.28	0.000
	Low	−3.21 ± 2.25
	Normal	0.00 ± 1.55
TIMP-3 protein	High	0.455 ± 0.062	19.43	0.000
	Low	0.517 ± 0.050
	Normal	0.592 ± 0.046

Averaged Ct value of normal samples was chosen as reference (ΔΔCt = 0, relative fold increase, RFI = 1). ΔΔCt was calculated by ΔCt subtracted with this reference. Our datum of relative fold index (RFI = 2 − ΔΔCt) obeyed skewed distribution, so we transformed our datum with log2(RFI) to normal distribution. miR-21 expression of tumor tissue and serum samples in the normal group, high and low invasive group has statistical differences and the comparison between each group is statistically significant (𝑃<0.01).
Tumor tissue TIMP-3 mRNA and protein expression levels in each group has statistical differences and the comparison between each group is statistically significant (𝑃<0.01).