Expression of specificity protein transcription factors in pancreatic cancer and their association in prognosis and therapy

Pancreatic cancer is an aggressive malignancy with poor prognosis. Pancreatic adenocarcinoma is one of the leading causes of cancer-related deaths in the United States. Due to the aggressive nature of this malignancy, there is a serious concern for identifying effective targets, and adopting novel strategies for therapy. Members of the Specificity Protein (Sp) family of transcription factors, Sp1, Sp3, and Sp4 regulate the expression of a number of genes associated with cancer cell proliferation, differentiation, and metastasis. Sp1 levels are upregulated in pancreatic cancer cell lines, and surgically resected human pancreatic adenocarcinoma. Sp1 overexpression in tumor tissues is associated with aggressive disease, poor prognosis and inversely correlated with survival. Sp1 is also known to affect angiogenesis by regulating the expression of vascular endothelial growth factor and its receptors. Results from clinical studies suggest Sp1 as new biomarker to identify aggressive pancreatic ductal adenocarcinoma. The pharmacological inhibition of Sp1 using agents such as celecoxib, mithramycin, curcumin, and tolfenamic acid has showed promising results in pre-clinical studies and demonstrated Sp transcription factors as potential targets for pancreatic cancer therapy. This review summarizes studies showing the association of Sp proteins with this malignancy, with a special emphasis on pre-clinical studies that tested strategies to target Sp transcription factors for inhibiting human pancreatic cancer cell proliferation and tumor growth in laboratory animals. The results showed remarkable efficacy and suggest that such approaches have the potential for high success in developing clinically relevant strategies for treating pancreatic cancer.