TGF-β1 and its signal molecules: are they correlated with the elasticity characteristics of breast lesions?

Shear wave elastography can evaluate tissue stiffness. Previous studies showed that the elasticity characteristics of breast lesions were related to the components of extracellular matrix which was regulated by transforming growth factor beta 1(TGF-β1) directly or indirectly. However, the correlation of the expression level of TGF-β1, its signal molecules and elasticity characteristics of breast lesions have rarely been reported. The purpose of this study was to investigate the correlation between the expression level of TGF-β1, its signal molecules, and the elasticity characteristics of breast lesions.

135 breast lesions in 130 patients were included. Elasticity parameters, including elasticity modulus, the elasticity ratio, the "stiff rim sign", were recorded before biopsy and surgical excision. The expression levels of TGF-β1 and its signal molecules, including Smad2/3, Erk1/2, p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase 2 (JNK2), phosphoinositide 3-kinase (PI3K), and protein kinase B (PKB/AKT) were detected by immunohistochemistry. The diagnostic performance of the expression level of those molecules and their correlation with the elasticity characteristics were analyzed.

Elasticity parameters and the expression levels of TGF- β1 and its signal molecules of benign lesions were lower than those of malignant lesions (P<0.0001). The expression levels of TGF- β1 and its signal molecules were correlated with elasticity parameters. The expression levels of TGF- β1 and its signal molecules in lesions with "stiff rim sign" were higher than those without "stiff rim sign" (P<0.05). And the expression levels of Smad2/3, Erk1/2, p38 MAPK, JNK2, PI3K and AKT were correlated with that of TGF- β1. The area under the curve for receiver operator characteristic curve of TGF-β1 and its signal molecules in the differentiation of malignant and benign breast lesions ranged from 0.920-0.960.

The expression levels of TGF-β1, its signal molecules of breast lesions showed good diagnostic performance and were correlated with the elasticity parameters. The expression levels of signal molecules were correlated with that of TGF- β1, which speculated that TGF- β1 might play an important role in the regulation of breast lesion elasticity parameters and multiple signal molecule expressions.