1
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Parkman GL, Turapov T, Kircher DA, Burnett WJ, Stehn CM, O’Toole K, Culver KM, Chadwick AT, Elmer RC, Flaherty R, Stanley KA, Foth M, Lum DH, Judson-Torres RL, Friend JE, VanBrocklin MW, McMahon M, Holmen SL. Genetic Silencing of AKT Induces Melanoma Cell Death via mTOR Suppression. Mol Cancer Ther 2024; 23:301-315. [PMID: 37931033 PMCID: PMC10932877 DOI: 10.1158/1535-7163.mct-23-0474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/08/2023] [Accepted: 10/30/2023] [Indexed: 11/08/2023]
Abstract
Aberrant activation of the PI3K-AKT pathway is common in many cancers, including melanoma, and AKT1, 2 and 3 (AKT1-3) are bona fide oncoprotein kinases with well-validated downstream effectors. However, efforts to pharmacologically inhibit AKT have proven to be largely ineffective. In this study, we observed paradoxical effects following either pharmacologic or genetic inhibition of AKT1-3 in melanoma cells. Although pharmacological inhibition was without effect, genetic silencing of all three AKT paralogs significantly induced melanoma cell death through effects on mTOR. This phenotype was rescued by exogenous AKT1 expression in a kinase-dependent manner. Pharmacological inhibition of PI3K and mTOR with a novel dual inhibitor effectively suppressed melanoma cell proliferation in vitro and inhibited tumor growth in vivo. Furthermore, this single-agent-targeted therapy was well-tolerated in vivo and was effective against MAPK inhibitor-resistant patient-derived melanoma xenografts. These results suggest that inhibition of PI3K and mTOR with this novel dual inhibitor may represent a promising therapeutic strategy in this disease in both the first-line and MAPK inhibitor-resistant setting.
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Affiliation(s)
- Gennie L. Parkman
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Tursun Turapov
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - David A. Kircher
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - William J. Burnett
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Christopher M. Stehn
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Kayla O’Toole
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Katie M. Culver
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Ashley T. Chadwick
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Riley C. Elmer
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Ryan Flaherty
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Karly A. Stanley
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Mona Foth
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - David H. Lum
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Robert L. Judson-Torres
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Dermatology, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | | | - Matthew W. VanBrocklin
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Martin McMahon
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Dermatology, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Sheri L. Holmen
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
- Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
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2
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Parkman GL, Turapov T, Kircher D, Burnett W, Stehn C, O'Toole K, Culver K, Chadwick A, Elmer R, Flaherty R, Foth M, Stanley K, Andtbacka R, Lum D, Judson-Torres R, McMahon M, Holmen S. Abstract 427: Newer generation mTOR inhibition represents effective therapeutic strategy for BRAF-mutant melanoma. Cancer Res 2023. [DOI: 10.1158/1538-7445.am2023-427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Abstract
Despite the advent of novel therapies, the five year survival rate for Stage IV melanoma remains at only 30%. This highlights the critical need for new therapeutics to treat this refractory disease. Aberrant activation of the PI3K-AKT pathway is common in melanoma, but efforts to drug this pathway have proven largely ineffective in clinical trials. In our study, we observed that pharmacological inhibition of AKT was ineffective whereas genetic silencing of all three AKT paralogs significantly abrogated melanoma cell growth and led to apoptosis through effects on mTORC signaling. This phenotype could be rescued by overexpression of AKT but was dependent on kinase activity. Interestingly, expression of the serine/threonine kinase SGK1 was increased following genetic suppression of AKT but only expression of activated SGK1 could rescue the lethal effect of AKT knockdown. SGK1 also increases tumor growth and decreases survival in a BRAFV600E-driven mouse model of melanoma. Despite our results suggesting that key proliferation of melanoma cells is through effects on mTOR, phase II clinical trials of mTOR inhibitors have not shown clinical advantage. This may be due to multiple reasons: firstly, mTOR inhibitors, such as rapamycin, function by destabilization of the mTORC1-Raptor complex while leaving the mTORC2-Rictor complex, intact. Rictor enables mTORC2 to directly phosphorylate Ser473, and facilitates Thr308 phosphorylation by PDK1. As both AKT and SGK are phosphorylated by mTORC2 and PDK1 to facilitate downstream signaling through mTORC1, residual activity of mTOR incompletely suppressed by rapamycin may still be sufficient to drive melanoma progression. Thus, we evaluated second and third generation mTORC inhibitors, including a dual PI3K/mTOR inhibitor, that target both mTORC1 and 2 complexes and lead to sustained suppression of PI3K>AKT signaling. The dual PI3K/mTORC inhibitor, Paxalisib, significantly reduced cell proliferation greater than combination AKT/SGK inhibition and resulted in increased overall survival in a BRAF-driven immunocompetent mouse model of melanoma (p=0.0003 vs vehicle). These results allow insight into compensatory signaling networks upon AKT inhibition and suggest that dual targeting of PI3K and both mTOR complexes may represent an effective and tolerable therapeutic strategy in this disease that could further be combined with standard of care targeted therapy.
Citation Format: Gennie L. Parkman, Tursun Turapov, David Kircher, William Burnett, Christopher Stehn, Kayla O'Toole, Katie Culver, Ashley Chadwick, Riley Elmer, Ryan Flaherty, Mona Foth, Karly Stanley, Robert Andtbacka, David Lum, Robert Judson-Torres, Martin McMahon, Sheri Holmen. Newer generation mTOR inhibition represents effective therapeutic strategy for BRAF-mutant melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 427.
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Affiliation(s)
| | - Tursun Turapov
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - David Kircher
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - William Burnett
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | | | - Kayla O'Toole
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - Katie Culver
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - Ashley Chadwick
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - Riley Elmer
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - Ryan Flaherty
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - Mona Foth
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - Karly Stanley
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - Robert Andtbacka
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - David Lum
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | | | - Martin McMahon
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - Sheri Holmen
- 1University of Utah Huntsman Cancer Institute, Salt Lake City, UT
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3
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Parkman GL, Foth M, Kircher DA, Holmen SL, McMahon M. The role of PI3'-lipid signalling in melanoma initiation, progression and maintenance. Exp Dermatol 2022; 31:43-56. [PMID: 34717019 PMCID: PMC8724390 DOI: 10.1111/exd.14489] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 09/11/2021] [Accepted: 10/19/2021] [Indexed: 01/03/2023]
Abstract
Phosphatidylinositol-3'-kinases (PI3Ks) are a family of lipid kinases that phosphorylate the 3' hydroxyl (OH) of the inositol ring of phosphatidylinositides (PI). Through their downstream effectors, PI3K generated lipids (PI3K-lipids hereafter) such as PI(3,4,5)P3 and PI(3,4)P2 regulate myriad biochemical and biological processes in both normal and cancer cells including responses to growth hormones and cytokines; the cell division cycle; cell death; cellular growth; angiogenesis; membrane dynamics; and autophagy and many aspects of cellular metabolism. Engagement of receptor tyrosine kinase by their cognate ligands leads to activation of members of the Class I family of PI3'-kinases (PI3Kα, β, δ & γ) leading to accumulation of PI3K-lipids. Importantly, PI3K-lipid accumulation is antagonized by the hydrolytic action of a number of PI3K-lipid phosphatases, most notably the melanoma suppressor PTEN (lipid phosphatase and tensin homologue). Downstream of PI3K-lipid production, the protein kinases AKT1-3 are believed to be key effectors of PI3'-kinase signalling in cells. Indeed, in preclinical models, activation of the PI3K→AKT signalling axis cooperates with alterations such as expression of the BRAFV600E oncoprotein kinase to promote melanoma progression and metastasis. In this review, we describe the different classes of PI3K-lipid effectors, and how they may promote melanomagenesis, influence the tumour microenvironment, melanoma maintenance and progression to metastatic disease. We also provide an update on both FDA-approved or experimental inhibitors of the PI3K→AKT pathway that are currently being evaluated for the treatment of melanoma either in preclinical models or in clinical trials.
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Affiliation(s)
- Gennie L. Parkman
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
| | - Mona Foth
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
| | - David A. Kircher
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
| | - Sheri L. Holmen
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
- Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
| | - Martin McMahon
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
- Department of Dermatology, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
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4
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Parkman GL, Kircher DA, Stehn CM, McMahon M, Holmen SL. Model-dependent outcomes: Sex as a biological variable in preclinical mouse models of melanoma. Pigment Cell Melanoma Res 2020; 34:655-658. [PMID: 33098202 DOI: 10.1111/pcmr.12940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/01/2020] [Accepted: 10/13/2020] [Indexed: 10/23/2022]
Affiliation(s)
- Gennie L Parkman
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - David A Kircher
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - Christopher M Stehn
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - Martin McMahon
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,Department of Dermatology, University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - Sheri L Holmen
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT, USA
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5
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Kircher DA, Trombetti KA, Silvis MR, Parkman GL, Fischer GM, Angel SN, Stehn CM, Strain SC, Grossmann AH, Duffy KL, McMahon M, Davies MA, Mendoza MC, VanBrocklin MW, Holmen SL. Abstract 2736: AKT1E17K activates focal adhesion kinase and promotes melanoma brain metastasis. Cancer Res 2020. [DOI: 10.1158/1538-7445.am2020-2736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Hyper-activation of the PI3K/AKT signaling pathway occurs in most metastatic melanomas and increased PI3K/AKT pathway activity correlates with disease progression. The serine/threonine kinase, AKT, represents a major signaling hub within the pathway and consists of three highly conserved paralogs that have both distinct and overlapping functions. Activating mutations of AKT1 and AKT3 occur in human melanoma but their role in melanoma formation and metastasis remains unclear. Using an established melanoma mouse model, we evaluated the ability of constitutively active E17K, E40K, or Q79K mutants of each AKT paralog to promote tumor progression and metastasis in the context of BRAFV600E expression and loss of Cdkn2a and Pten. Expression of AKT1E17K promoted highly aggressive melanomas that metastasized to the lungs and brain. This metastatic phenotype was not significantly observed in the case of other mutant AKT-positive tumors, suggesting that the AKT paralogs have distinct, non-overlapping roles in the development of melanoma metastases. AKT1E17K-positive tumors showed AKT1E17K-dependent up-regulation of multiple focal adhesion (FA) factors, which are key components of focal adhesions and established stimulators of cell motility, as well as phosphorylation of focal adhesion kinase (FAK). Ectopic expression of AKT1E17K in non-metastatic melanoma cells increased cell invasion, a phenotype abrogated by pharmacological inhibition of AKT or FAK. These findings strongly suggest that one mechanism by which AKT1 promotes melanoma metastasis is through regulation and activation of proteins involved in focal adhesions. This has important implications for the development of therapeutic strategies aimed at preventing or treating disseminated disease.
Citation Format: David A. Kircher, Kirby A. Trombetti, Mark R. Silvis, Gennie L. Parkman, Grant M. Fischer, Stephanie N. Angel, Christopher M. Stehn, Sean C. Strain, Allie H. Grossmann, Keith L. Duffy, Martin McMahon, Michael A. Davies, Michelle C. Mendoza, Matthew W. VanBrocklin, Sheri L. Holmen. AKT1E17K activates focal adhesion kinase and promotes melanoma brain metastasis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2736.
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Vaishnavi A, Scherzer MT, Kinsey CG, Parkman GL, Truong A, Ghazi P, Schuman S, Battistone B, Garrido-Laguna I, McMahon M. Inhibition of MEK1/2 Forestalls the Onset of Acquired Resistance to Entrectinib in Multiple Models of NTRK1-Driven Cancer. Cell Rep 2020; 32:107994. [PMID: 32755586 PMCID: PMC7478141 DOI: 10.1016/j.celrep.2020.107994] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 05/11/2020] [Accepted: 07/15/2020] [Indexed: 12/15/2022] Open
Abstract
NTRK1 gene fusions are actionable drivers of numerous human malignancies. Here, we show that expression of the TPR-NTRK1 fusion kinase in immortalized mouse pancreatic ductal epithelial (IMPE) (pancreas) or mouse lung epithelial (MLE-12) cells is sufficient to promote rapidly growing tumors in mice. Both tumor models are exquisitely sensitive to targeted inhibition with entrectinib, a tropomyosin-related kinase A (TRKA) inhibitor. Initial regression of NTRK1-driven tumors is driven by induced expression of BIM, such that BIM silencing leads to a diminished response to entrectinib in vivo. However, the emergence of drug-resistant disease limits the long-term durability of responses. Based on the reactivation of RAF>MEK>ERK signaling observed in entrectinib-treated tumors, we show that the combination of entrectinib plus the MEK1/2 inhibitor cobimetinib dramatically forestalls the onset of drug resistance in vivo. Collectively, these data provide a mechanistic rationale for rapid clinical deployment of combined inhibition of TRKA plus MEK1/2 in NTRK1-driven cancers.
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Affiliation(s)
- Aria Vaishnavi
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Michael T Scherzer
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Conan G Kinsey
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA; Department of Internal Medicine, Division of Oncology, University of Utah, Salt Lake City, UT 84112, USA
| | - Gennie L Parkman
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Amanda Truong
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Phaedra Ghazi
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Sophia Schuman
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Benjamin Battistone
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Ignacio Garrido-Laguna
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA; Department of Internal Medicine, Division of Oncology, University of Utah, Salt Lake City, UT 84112, USA
| | - Martin McMahon
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA; Department of Dermatology, University of Utah, Salt Lake City, UT 84112, USA.
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7
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Kircher DA, Trombetti KA, Silvis MR, Parkman GL, Fischer GM, Angel SN, Stehn CM, Strain SC, Grossmann AH, Duffy KL, Boucher KM, McMahon M, Davies MA, Mendoza MC, VanBrocklin MW, Holmen SL. AKT1 E17K Activates Focal Adhesion Kinase and Promotes Melanoma Brain Metastasis. Mol Cancer Res 2019; 17:1787-1800. [PMID: 31138602 PMCID: PMC6726552 DOI: 10.1158/1541-7786.mcr-18-1372] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 03/18/2019] [Accepted: 05/22/2019] [Indexed: 02/03/2023]
Abstract
Alterations in the PI3K/AKT pathway occur in up to 70% of melanomas and are associated with disease progression. The three AKT paralogs are highly conserved but data suggest they have distinct functions. Activating mutations of AKT1 and AKT3 occur in human melanoma but their role in melanoma formation and metastasis remains unclear. Using an established melanoma mouse model, we evaluated E17K, E40K, and Q79K mutations in AKT1, AKT2, and AKT3 and show that mice harboring tumors expressing AKT1E17K had the highest incidence of brain metastasis and lowest mean survival. Tumors expressing AKT1E17K displayed elevated levels of focal adhesion factors and enhanced phosphorylation of focal adhesion kinase (FAK). AKT1E17K expression in melanoma cells increased invasion and this was reduced by pharmacologic inhibition of either AKT or FAK. These data suggest that the different AKT paralogs have distinct roles in melanoma brain metastasis and that AKT and FAK may be promising therapeutic targets. IMPLICATIONS: This study suggests that AKT1E17K promotes melanoma brain metastasis through activation of FAK and provides a rationale for the therapeutic targeting of AKT and/or FAK to reduce melanoma metastasis.
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Affiliation(s)
- David A Kircher
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Kirby A Trombetti
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Mark R Silvis
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Gennie L Parkman
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Grant M Fischer
- Department of Melanoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Stephanie N Angel
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Christopher M Stehn
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Sean C Strain
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Allie H Grossmann
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
- ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, Utah
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Keith L Duffy
- Department of Dermatology, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Kenneth M Boucher
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Internal Medicine, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Martin McMahon
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Dermatology, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Michael A Davies
- Department of Melanoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Michelle C Mendoza
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Matthew W VanBrocklin
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, Utah
| | - Sheri L Holmen
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah.
- Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah
- Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, Utah
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