Prognostic Value of IMP3 and Its Role as an Epithelial-Mesenchymal Transition Promoter in Breast Carcinoma

Breast carcinoma is now the most common cancer in the world. In view of its high mortality, there is a need to identify new prognostic biomarkers. Both IMP3 and SLUG have been implicated in cancer metastasis. This was a retrospective study conducted on 60 breast carcinoma cases using tissue microarrays. Demographic and clinicopathological details were recorded. Immunohistochemistry for IMP3 and SLUG was performed and evaluated in terms of percentage-cell-positivity and intensity of staining. A proforma was used to store data and was analyzed using SPSS v20. IMP3 positivity was found in 87% breast carcinoma cases and was significantly associated with tumor size (p = 0.03) and TNM stage (p = 0.024). IMP3 staining intensity showed significant association with histological grade (p = 0.009), TNM stage (p = 0.036), and molecular subtype (p = 0.03). SLUG immunoexpression was seen in 90% breast carcinoma cases and was significantly associated with TNM stage (p = 0.006). SLUG staining intensity was significantly associated with age (p = 0.025) and TNM stage (p = 0.004). IMP3 and SLUG immunopositivity and their staining intensities were significantly associated (p <0.001, p <0.001). IMP3 and SLUG percentage cell positivities were also significantly correlated (p <0.001). IMP3 and SLUG are, thus, poor prognostic markers with a role in tumor invasiveness and aggressiveness via epithelial-mesenchymal transition. Hence, IMP3 and SLUG-based targeted therapies may be useful in the treatment of breast carcinoma.