Decreased galectin-3 expression during the progression of cervical neoplasia

Purpose: Galectin-3 is expressed widely in epithelial and immune cells and the level of expression varies in many cancer cells relative to the normal tissues from which they arise. We investigated whether the expression of galectin-3 is associated with the progression of cervical neoplasia. Methods: Galectin-3 expression was evaluated in fresh frozen tissues of cervical carcinoma using real-time quantitative RT-PCR. In addition, galectin-3 expression was evaluated at the protein level by immunohistochemistry in 90 formalin-fixed paraffin-embedded cervical tissues, 10 normal cervical specimens, 20 low-grade squamous intraepithelial lesions (LSILs), 20 high-grade squamous intraepithelial lesions (HSILs), and 40 invasive squamous cell carcinomas (ISCCs). Results: Real-time quantitative RT-PCR revealed that galectin-3 expressions in tumor cells were significantly downregulated compared with corresponding normal tissue (P = 0.005). Moreover, immunohistochemistry showed that galectin-3 expression was strong in all normal cervical squamous epithelia and gradually decreased in accordance with the histopathologic grades in order LSIL > HSIL > ISCC (P < 0.001). Conclusions: These data constitute the first observation that the expression of galectin-3 is downregulated in cervical cancer tissues and suggest that the decreased expression of this galactoside-binding lectin is associated with the progression of cervical neoplasia.