Sumoylation of Specificity Protein 1 Augments Its Degradation by Changing the Localization and Increasing the Specificity Protein 1 Proteolytic Process

Overexpression of Sp1 leads to p53‐dependent apoptosis in cancer cells

“…Sp1 commonly undergoes posttranslational modifications such as phosphorylation, glycosylation, acetylation, ubiquitination, and sumoylation. [2][3][4][5][6] Numerous studies have documented that Sp1 activity and/or expression levels are elevated in human pancreatic cancer, breast cancer, colorectal cancer, gastric carcinoma, hepatocellular carcinoma, and thyroid carcinoma.…”

“…Sp1 commonly undergoes posttranslational modifications such as phosphorylation, glycosylation, acetylation, ubiquitination, and sumoylation. [2][3][4][5][6] Numerous studies have documented that Sp1 activity and/or expression levels are elevated in human pancreatic cancer, breast cancer, colorectal cancer, gastric carcinoma, hepatocellular carcinoma, and thyroid carcinoma. [7][8][9][10][11][12] Although Sp1 regulates a number of oncogenes such as those coding for the vascular endothelial growth factor, urokinase plasminogen activator (uPA), uPA receptor, and epithelial growth factor receptor, [13][14][15] it also induces the expression of many tumor suppressor genes such as p27 kip1 , p21 WAF1/CIP1 , p16 INK4a , and pp2a-c. [16][17][18] In addition, the promoters of many proapoptotic genes have been found to contain Sp1-binding elements; for instance, fas, fas ligand, bax, and caspase 3.…”

“…Sp1 commonly undergoes posttranslational modifications such as phosphorylation, glycosylation, acetylation, ubiquitination, and sumoylation. [2][3][4][5][6] Numerous studies have documented that Sp1 activity and/or expression levels are elevated in human pancreatic cancer, breast cancer, colorectal cancer, gastric carcinoma, hepatocellular carcinoma, and thyroid carcinoma.7-12 Although Sp1 regulates a number of oncogenes such as those coding for the vascular endothelial growth factor, urokinase plasminogen activator (uPA), uPA receptor, and epithelial growth factor receptor, [13][14][15] it also induces the expression of many tumor suppressor genes such as p27 kip1 , p21 WAF1/CIP1 , p16 INK4a , and pp2a-c. [16][17][18] In addition, the promoters of many proapoptotic genes have been found to contain Sp1-binding elements; for instance, fas, fas ligand, bax, and caspase 3.19,20 Interestingly, it has been found that Sp1 can also induce the expression of many antiapoptotic genes (such as survivin, bcl-x, and bcl-w).20,21 Moreover, several recent studies have indicated that the overexpression of Sp1 causes apoptotic cell death in nontransforming cells, but the downregulation of the overexpressed Sp1 protein in human fibrosarcoma cell lines inhibits tumor formation. 13,22 Therefore, the effect of Sp1 overexpression on apoptosis regulation in transforming cells remains controversial, and the detailed mechanism of this process remains unclear.…”

MicroRNA-337 inhibits cell proliferation and invasion of cervical cancer through directly targeting specificity protein 1

“…42,49,50 Previous studies indicate that the expression of Sp1 is increased in cervical cancer tissues. 32 Moreover, Sp1 is involved in cervical cancer cell proliferation, apoptosis, radiosensitivity, and metastasis. 23,33,[51][52][53] Our results suggested that miR-337 inhibited cell proliferation and invasion through reducing the Sp1 expression.…”

Beta-Lapachone Suppresses Non-small Cell Lung Cancer Proliferation through the Regulation of Specificity Protein 1

“…26) Since Sp1 accumulates in several types of cancers, 27) an understanding of the Sp1 regulatory network may provide novel insight into cancer treatment.…”