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Audrey Cox,
Elena Kurenova,
Maria Zajac-Kaye,
Timothy J Garrett,
David A Ostrov,
Steven N Hochwald, William G Cance,
Nicholas Lawrence,
Carl Nyberg,
Deniz A Ucar,
Nicole Massoll,
Said M Sebti
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Deniz A Ucar,
Elena Kurenova,
Timothy J Garrett,
William G Cance,
Carl Nyberg,
Audrey Cox, Nicole Massoll,
David A Ostrov,
Nicholas Lawrence,
Said M Sebti,
Maria Zajac-Kaye,
Steven N Hochwald
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ABSTRACT: FAK (focal adhesion kinase) and IGF-1R (insulin-like growth factor receptor-1) directly interact with each other and thereby activate crucial signaling pathways that benefit cancer cells. Inhibition of FAK and IGF-1R function has been shown to significantly decrease cancer cell proliferation and increase sensitivity to chemotherapy and radiation treatment. As a novel approach in human melanoma, we evaluated the effect of a small-molecule compound that disrupts the protein interaction of FAK and IGF-1R. Previously, using virtual screening and functional testing, we identified a lead compound (INT2-31) that targets the known FAK-IGF-1R protein interaction site. We studied the ability of this compound to disrupt FAK-IGF-1R protein interactions, inhibit downstream signaling, decrease human melanoma cell proliferation, alter cell cycle progression, induce apoptosis and decrease tumor growth in vivo. INT2-31 blocked the interaction of FAK and IGF-1R in vitro and in vivo in melanoma cells and tumor xenografts through precluding the activation of IRS-1, leading to reduced phosphorylation of AKT upon IGF-1 stimulation. As a result, INT2-31 significantly inhibited cell proliferation and viability (range 0.05-10 μM). More importantly, 15 mg/kg of INT2-31 given for 21 d via intraperitoneal injection disrupted the interaction of FAK and IGF-1R and effectively decreased phosphorylation of tumor AKT, resulting in significant melanoma tumor regression in vivo. Our data suggest that the FAK-IGF-1R protein interaction is an important target, and disruption of this interaction with a novel small molecule (INT2-31) has potential anti-neoplastic therapeutic effects in human melanoma.
Cell cycle (Georgetown, Tex.) 09/2012; 11(17):3250-9. · 5.36 Impact Factor
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Deniz A Ucar,
Elena Kurenova,
Timothy J Garrett,
William G Cance,
Carl Nyberg,
Audrey Cox, Nicole Massoll,
David A Ostrov,
Nicholas Lawrence,
Said Sebti,
Steven N Hochwald
[show abstract]
[hide abstract]
ABSTRACT: Previously, we have shown that FAK (focal adhesion kinase) and IGF-1R (insulin-like growth factor receptor-1) directly interact with each other and, thereby, activate crucial signaling pathways that benefit cancer cells. Inhibition of FAK and IGF-1R function have shown to significantly decrease cancer cell proliferation and increase sensitivity to chemotherapy and radiation treatment. In this study, as a novel approach in human melanoma, we evaluated the effect of a small molecule compound that disrupts the interaction of FAK and IGF-1R. Using virtual screening and functional testing, we identified a lead compound (INT2-31) that targets the known FAK-IGF-1R protein interaction site. We studied the ability of this compound to disrupt FAK-IGF-1R protein interactions, inhibit downstream signaling, decrease human melanoma cell proliferation, induce apoptosis, and decrease tumor growth in vivo. Based on GST pulldowns with purified protein fragments of FAK and IGF-1R and from co-immunoprecipitation assays from melanoma cells, INT2-31 blocked the interaction of FAK and IGF-1R and precluded activation of IRS-1 leading to reduced phosphorylation of AKT upon IGF-1 stimulation. As a result, INT2-31 significantly inhibited cell proliferation and viability (range 0.05-10μM). More importantly, 15mg/kg of INT2-31 given for 21 days via intraperitoneal injection disrupted the interaction of FAK and IGF-1R and effectively decreased phosphorylation of tumor AKT resulting in significant melanoma tumor regression in vivo (p<0.05). Our data suggest that FAK-IGF-1R protein interaction can be identified as an important target and disruption of this interaction with a small molecule has potential anti-neoplastic therapeutic effects in human melanoma.
Carcinogenesis 06/2011; · 5.70 Impact Factor
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ABSTRACT: Focal adhesion kinase (FAK) is a cytoplasmic tyrosine kinase that is overexpressed in many types of tumors, including pancreatic cancer, and plays an important role in cell adhesion and survival signaling. Pancreatic cancer is a lethal disease and is very resistant to chemotherapy, and FAK has been shown recently to assist in tumor cell survival. Therefore, FAK is an excellent potential target for anti-cancer therapy. We identified a novel small molecule inhibitor (1,2,4,5-Benzenetetraamine tetrahydrochloride, that we called Y15) targeting the main autophosphorylation site of FAK and hypothesized that it would be an effective treatment strategy against human pancreatic cancer. Y15 specifically blocked phosphorylation of Y397-FAK and total phosphorylation of FAK. It directly inhibited FAK autophosphorylation in a dose- and time-dependent manner. Furthermore, Y15 increased pancreatic cancer cell detachment and inhibited cell adhesion in a dose-dependent manner. Y15 effectively caused human pancreatic tumor regression in vivo, when administered alone and its effects were synergistic with gemcitabine chemotherapy. This was accompanied by a decrease in Y397-phosphorylation of FAK in the tumors treated with Y15. Thus, targeting the Y397 site of FAK in pancreatic cancer with the small molecule inhibitor, 1,2,4,5-Benzenetetraamine tetrahydrochloride, is a potentially effective treatment strategy in this deadly disease.
Cell cycle (Georgetown, Tex.) 09/2009; 8(15):2435-43. · 5.36 Impact Factor
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ABSTRACT: Vascular endothelial growth factor receptor-3 is a receptor tyrosine kinase that is overexpressed in some human carcinomas, but its role in tumorigenesis has not been fully elucidated. We examined VEGFR-3 expression in normal, nonneoplastic and early stage malignant breast tissues and have shown that VEGFR-3 upregulation in breast cancer preceded tumor cell invasion, suggesting that VEGFR-3 may function as a survival signal. We characterized the biological effects of VEGFR-3 over-expression in human breast cancer cells based on two approaches: gain of function by overexpressing VEGFR-3 in MCF-7 breast cancer cells and loss of function by RNAi-mediated silencing of VEGFR-3 in MCF-7-VEGFR-3 and BT474 cells. VEGFR-3 overexpression increased cellular proliferation by 40% when MCF7-VEGFR-3 cells were compared to parental MCF7 cells, and proliferation was reduced by more than 40% when endogenous VEGFR-3 was downregulated in BT474 cells. VEGFR-3 overexpression promoted a three-fold increase in motility and invasion and both motility and invasion were inhibited by downregulation of VEGFR-3. Furthermore, VEGFR-3 overexpression promoted cellular survival under stress conditions induced by staurosporine treatment and led to anchorage-independent growth. VEGFR-3 overexpression dramatically increased tumor formation in both hormone-dependent and independent xenograft models. With estrogen stimulation, MCF7-VEGFR-3 xenografts were ten times larger than control xenografts. Finally, downregulation of VEGFR-3 expression in both xenograft model cell lines led to a significant reduction of tumor growth. For the first time, we have demonstrated that VEGFR-3 overexpression promotes breast cancer cell proliferation, motility, survival, anchorage-independent growth and tumorogenicity in the absence of ligand expression.
Cell cycle (Georgetown, Tex.) 08/2009; 8(14):2266-80. · 5.36 Impact Factor
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ABSTRACT: Idiopathic granulomatous mastitis, also known as idiopathic granulomatous lobular mastitis, is a benign breast lesion that represents both a diagnostic and therapeutic dilemma. We report two cases of granulomatous mastitis recently evaluated and managed at our institution. To better understand this rare disease, we analyzed treatment outcomes in reported cases of granulomatous mastitis. One hundred sixteen cases were subsequently analyzed. Primary management strategies included observation (n = 9), steroids (n = 29), partial mastectomy (n = 75), and mastectomy (n = 3). Success rates with each treatment were observation, 56 per cent; steroids, 42 per cent; partial mastectomy, 79 per cent; and mastectomy, 100 per cent. Based on this analysis, we propose a clinically useful algorithm for both workup and management of these challenging cases.
The American surgeon 09/2007; 73(8):798-802. · 1.28 Impact Factor
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Thyroid 01/2007; 16(12):1319-20. · 4.79 Impact Factor
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ABSTRACT: Successful treatment of MTC depends heavily on early diagnosis and treatment. Often, this is not possible for sporadic MTC; however, genetic testing for hereditary MTC makes this possible if genetic carriers have surgery before C cells undergo malignant transformation. All patients who have MTC should be tested for RET mutations, including putative sporadic cases. The leukocytes of suspected carriers and sporadic MTC cases should be tested for MEN2-associated germ-line mutations by polymerase chain reaction amplification of the appropriate RET gene exons, including 10, 11,13, 14, 15, and 16 (see Table I). When a RET mutation is found, all first-degree relatives must be screened to determine which individuals carry the gene. If these exons are negative, the other 15 should be sequenced because a small risk of hereditary MTC remains if no germ-line mutation is found. The probability that a first-degree relative will inherit an autosomal dominant gene for MTC from an individual who has sporadic MTC in whom no germ-line mutation is found is 0.18% . Patients who have MEN2B or RET codon 883 or 918 mutation should have a total thyroidectomy within the first 6 months of life, preferably within the first month of life. Patients who have 634 mutations, which account for approximately 70% of all MTC mutations, should undergo thyroidectomy by age 5 years. The recommendations for the timing of prophylactic thyroidectomy are not consistent for the less common mutations (see Table 2). There is a balance between performing prophylactic thyroidectomy earlier than at the youngest age at with MTC has been reported to occur for a specific RET mutation (see Fig. 3 and Table 2) and the complications of thyroidectomy, including permanent hypoparathyroidism and laryngeal nerve damage. Preoperative measurement of plasma free metanephrine and neck ultrasonography always should be done if the diagnosis of MTC is known preoperatively. Initial treatment of MTC is total thyroidectomy, regardless of its genetic type or putative sporadic nature, because surgery offers the only chance for a cure. Treatment with 1311 has no place in the management of MTC. Plasma CT measurements provide an accurate estimate of tumor burden and are especially useful in identifying patients who have residual tumor. Pentagastrin- or calcium-stimulated plasma CT testing is useful in identifying CCH or early MTC in carriers of RET mutations that are associated with late onset MTC. Pheochromocytoma may occur before or after MTC and is an important cause of mortality, even in young patients. HPT is an important aspect of MEN2A and requires surgery according to current guidelines for the management of primary HPT. Early thyroidectomy and appropriate management of pheochromocytoma clearly have modified the course of this disease, but more research is necessary in kindreds who have rare MTC mutations. Moreover, new treatments for widespread MTC are necessary because current chemotherapy agents offer little benefit. New drugs that lock the action of tyrosine kinase offer some hope.
Clinics in Laboratory Medicine 04/2004; 24(1):49-83. · 1.97 Impact Factor
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ABSTRACT: Cystic thyroid nodules are common, comprising as many as 40% of thyroid nodules encountered by the endocrinologist. Their differential diagnosis is relatively broad and includes lesions that may not fit a stereotypical presentation, such as intrathyroidal thyroglossal duct cysts, branchial cleft cysts that are close to the midline, and cystic lesions that are malignant. Benign cystic thyroid nodules not infrequently present with symptoms and signs that mimic an aggressive thyroid cancer, including pressure symptoms and rapid growth; however, a cystic papillary thyroid carcinoma may provide few clues of its malignant nature, including a soft consistency to palpation and little or no apparent growth over the course of several years. The physical and biochemical features of the aspirated fluid of a nodule provide little diagnostic information; both benign and malignant lesions may yield grossly bloody aspirates or translucent yellow fluid. Cystic thyroid nodules not only have a higher than usual likelihood of yielding cytology specimens that are inadequate for diagnosis but also have higher than usual rates of false-negative cytology specimens. However, using a careful clinical assessment, ultrasonography, Doppler studies and ultrasound-guided fine-needle aspiration biopsy, the malignant or benign nature of most cystic thyroid nodules can be identified. This article reviews the differential diagnosis, diagnostic approach, and treatment of cystic nodules.
The Endocrinologist 04/2002; 12(3):185-198. · 0.09 Impact Factor
