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11 citation(s) found for "Crowder, RJ".

Pathogenic MAPK8IP3 variants drive distinct motor and behavioral phenotypes in humans and mice
Watkins, Lyndsay R. , Geltzeiler, Alexa, Patel, Priya, Ortiz-Perez, Judit, Schmidt, Danielle, Schmitz, C, Aguilar, Jalen, Ghanta, Shraddha, Chung, Wendy. K., Gowrishankar, Swetha , Lambert, Laura, Crowder, Camerron M. , Geltzeiler, Alexa , Ortiz, Judit Perez, Chung, Wendy K.

No container title available | July 25, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.64898/2026.07.20.739682 Get It

ABSTRACT Pathogenic variants in MAPK8IP3 (JIP3) cause Neurodevelopmental Disorder with or without variable Brain Abnormalities (NEDBA), characterized by cognitive impairment, global developmental delay, motor dysfunction, abnormal muscle tone, behavioral dysregulation including autism and attention deficit hyperactivity disorder (ADHD), seizures, and structural brain abnormalities. While more than 30 largely de novo MAPK8IP3 variants have been reported, the functional impact of variants across JIP3 protein structural domains is poorly defined. To address this knowledge gap, we compare clinical features of individuals with a truncating (p.E27X) or one of two missense (p.R578C and p.R1146C) variants from distinct JIP3 functional protein domains to corresponding knock-in mouse models. Our findings showed that all individuals, regardless of variant type, exhibited delays in language and gross motor function, but individual variants were associated with distinct motor, cognitive, and psychiatric symptoms. Corresponding homozygous p.E27X and p.R1147C variant mice resulted in embryonic lethality, consistent with essential roles for JIP3 in early neurodevelopment. Behavioral characterization of viable heterozygous mice revealed variant-specific locomotor, motor coordination, and hindlimb clasping defects that closely recapitulate clinical observations. Heterozygous p.R579C mice exhibited reduced locomotion, impaired motor performance, and hypertonia-like clasping, mirroring human motor deficits. In contrast, p.R1147C mice displayed hyperactivity, hindlimb clasping, and decreased brain weight, paralleling human clinical features. Together, our findings demonstrate that while distinct MAPK8IP3 variants lead to some shared phenotypes, they are also associated with distinct phenotypes that could reveal domain-specific aspects of JIP3 function. This work establishes the first domain-resolved in vivo rodent models of NEDBA and provides a validated translational platform for mechanistic investigation and preclinical therapeutic testing.
The Future of Forensic Anthropology Practice and Education: Competencies, Certification, and Licensure
Langley, Natalie R. , Tersigni‐Tarrant, MariaTeresa A., Passalacqua, Nicholas V. , Crowder, Christian M., Garvin, Heather M. , McQuade, Wendy E. P., Martinez, Miriam Soto , Pilloud, Marin A , McQuade, Wendy E. P.

American Journal of Biological Anthropology | March 20, 2025 | Volume: 186 | Issue: 3 | Pages: No page available

10.1002/ajpa.70034 | PMID 40108948 Get It

ABSTRACTForensic anthropology must embrace standards and credentialing that align with other medicolegal disciplines, such as forensic pathology and forensic odontology. This involves establishing itself more firmly as an essential specialty in the medicolegal system and limiting practice to qualified professionals. Without educational or professional requirements to practice forensic anthropology, the competencies of those involved in medicolegal cases vary, despite the potentially serious legal impact of errors. Negligent work can impede decedent identification or wrongly convict or free a suspect. Erroneous and unprofessional work also misrepresents the field and may deter agencies from utilizing forensic anthropologists. This commentary aims to convey the need to further professionalize forensic anthropology through the standardization of education, qualifications, and practice. Differences between certification and licensure and their implications are discussed. Recent and upcoming developments in the field highlight progress, including the development of a multi‐level certification system and list of core competencies by the American Board of Forensic Anthropology (ABFA). Additionally, the Anthropology subcommittee of the Organization of Scientific Area Committees for forensic science (OSAC) is developing a standard for qualifications in forensic anthropology. These developments emphasize the importance of certification and standardization in education and training for the advancement of forensic anthropology. Standardization efforts such as these will foster a cohesive, respected practice to serve the evolving needs of the medicolegal system.
Chronic Pain, Cognition, and the Value of Occupational Therapy
Crowder, Tanya, Lacayo, Elke, Perez, Rachel , Sletten, Christopher D.

American Journal of Occupational Therapy | September 9, 2020 | Volume: 74 | Issue: 1_suppl | Pages: No page available

10.5014/ajot.2020.74s1-po9725 Get It

Date Presented 03/28/20 Cognitive difficulties are commonly reported by individuals with chronic pain. An interdisciplinary pain rehabilitation program (IPRP) that includes OT can be an effective strategy for improving cognitive performance. This case series examines change in cognitive performance for two individuals following a three-week IPRP. OTs provide group-based education with an emphasis on function. This approach successfully enhances cognitive performance and can potentially be used as an OT treatment in other settings. Primary Author and Speaker: Elke Lacayo Additional Authors and Speakers: Tanya Crowder Contributing Authors: Rachel Perez, Christopher Sletten
Abstract 5240: Functional and therapeutic significance of ESR1 gene fusions in breast cancer
Shao, Jieya , Iglesia, Michael D. , Chan, Doug W. , Jin, Cao , Singh, Purba , He, Xiaping , Kosaka, Yoshimasa , Matsunuma, Ryoichi , Crowder, Robert J., Phommaly, Chanpheng, Gonçalves, Rodrigo , Romalho, Susana, Peres, Raquel Mary Rodrigues , Punturi, Nindo , Schmidt, Cheryl, Bartram, Alex, Jou, Eric , Lai, W V., Rogers, Anna , Tobias, Ethan, Parikh, Poojan A., Li, Shunqiang , Cynthia, X. , Thompson, Emily A. , Kavuri, Shyam M. , Creighton, Chad J. , Maher, Christopher A. , Haricharan, Svasti , Lei, Jonathan T. , Zhang, Jin , Anurag, Meenakshi , Hoog, Jeremy , Lai, W V., Hampton, Oliver , Davies, Sherri R. , Suman, Vera J. , Hunt, Kelly K. , Watson, Mark A. , Hoadley, Katherine A. , Thompson, E A., Chen, Xi , Perou, Charles M. , Ellis, Matthew J.

Cancer Research | August 17, 2018 | Volume: 78 | Issue: 13_Supplement | Pages: 5240-5240

10.1158/1538-7445.am2018-5240 Get It

Abstract RNA sequencing detects estrogen receptor alpha gene (ESR1) fusion transcripts in estrogen receptor positive (ER+) breast cancer but their role in disease pathogenesis remains unclear. Herein we examined multiple in-frame and out-of-frame ESR1 fusions and found only two, both identified in advanced endocrine treatment resistant disease, encoded stable and functional in-frame fusion proteins. In both examples, ESR1-e6>YAP1 and ESR1-e6>PCDH11X, the N-terminal, DNA binding and dimerization motifs encoded by exons 2-6 were fused to C-terminal sequences from the partner gene. Functional properties included estrogen-independent growth, constitutive expression of ER target genes, anti-estrogen resistance, induction of cellular motility in vitro and the development of lung metastasis in vivo. Chromatin immunoprecipitation and RNA sequencing experiments showed both fusions uniquely activated a metastasis-associated transcriptional program. ESR1-e6>YAP1 and ESR1-e6>PCDH11X-induced growth remained sensitive to a CDK4/6 inhibitor, palbociclib, and a patient-derived xenograft (PDX) expressing the ESR1-e6>YAP1 fusion was also responsive. Transcriptionally active ESR1 fusions therefore trigger both endocrine therapy resistance and metastatic progression explaining the association with fatal disease progression, although CDK4/6 inhibitor treatment is predicted to be effective. Citation Format: Jonathan T. Lei, Jieya Shao, Jin Zhang, Michael Iglesia, Doug W. Chan, Jin Cao, Meenakshi Anurag, Purba Singh, Xiaping He, Yoshimasa Kosaka, Ryoichi Matsunuma, Robert Crowder, Jeremy Hoog, Chanpheng Phommaly, Rodrigo Goncalves, Susana Romalho, Raquel M. Peres, Nindo Punturi, Cheryl Schmidt, Alex Bartram, Eric Jou, W V. Lai, Oliver Hampton, Anna Rogers, Ethan Tobias, Poojan Parikh, Sherri R. Davies, Shunqiang Li, Cynthia X. Ma, Vera Suman, Kelly K. Hunt, Mark A. Watson, Katherine A. Hoadley, E A. Thompson, Xi Chen, Shyam M. Kavuri, Chad J. Creighton, Christopher A. Maher, Charles M. Perou, Svasti Haricharan, Matthew J. Ellis. Functional and therapeutic significance of ESR1 gene fusions in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5240.
Abstract PD8-03: ESR1 gene fusions drive endocrine therapy resistance and metastasis in breast cancer
Lei, JT, Shao, Jieya , Zhang, J, Iglesia, Michael D. , Cao, Jin , Haricharan, Svasti , Kavuri, SM, Matsunuma, Ryoichi , Schmidt, Cecilia, Kosaka, Yoshimasa , Crowder, RJ, Hoog, J, Phommaly, Chanpheng, Gonçalves, Rodrigo , Ramalho, Susana , Rodrigues-Peres, RM, Lai, W-C, Rogers, Anna , Tobias, Ethan, Parikh, Poojan A., Davies, S. J. , Ma, C, Suman, VJ, Watson, Mark , Hoadley, KA, Thompson, Andrew , Perou, CM, Creighton, CJ, Ellis, MJ, Chan, David W. , Anurag, Meenakshi , Singh, Pankaj Kumar , Hampton, Oliver , Ma, C, Hunt, Kelly K. , Watson, M, Hoadley, Katherine A. , Maher, Christopher G.

Cancer Research | February 15, 2018 | Volume: 78 | Issue: 4_Supplement | Pages: PD8-03-PD8-03

10.1158/1538-7445.sabcs17-pd8-03 Get It

Abstract Background. Dysregulation of the estrogen receptor gene (ESR1) is an established mechanism of inducing endocrine therapy resistance. We previously discovered a chromosomal translocation event generating an estrogen receptor gene fused in-frame to C-terminal sequences of YAP1 (ESR1-YAP1) that contributed to endocrine therapy resistance in estrogen receptor positive (ER+) breast cancer models. This study compares functional, transcriptional, and pharmacological properties of additional ESR1 gene fusion events of both early stage (ESR1-NOP2) late stage (ESR1-YAP1 and ESR1-PCDH11x) breast cancers to gain a better understanding of therapeutic resistance and metastasis. Understanding the role of ESR1 fusions in inducing metastasis is critical, since the primary cause of death in breast cancer patients is through metastasis to distant sites. Methods. RNA-seq screens identified ESR1 fusions from early and late stage, endocrine therapy resistant breast tumor samples. Functional experiments were conducted using ER+ breast cancer cell lines, xenograft, and PDX models to test the ability of ESR1 fusions to induce therapeutic resistance and metastasis. ChIP-seq and RNA-seq were performed to examine transcriptional properties and differential gene expression induced by the fusions which directed subsequent pharmacological experiments with a CDK4/6 inhibitor. Results. ESR1-YAP1 and ESR1-PCDH11x promoted estrogen-independent and fulvestrant-resistant growth in vitro and induced greater tumor growth and increased metastatic capacity to the lungs of xenografted mice. In contrast, the ESR1-NOP2 fusion was sensitive to low estrogen conditions in vitro, and did not promote tumor growth. RNA-seq profiling revealed E2F targets pathway as the most highly enriched pathway induced by the ESR1 fusions. IHC revealed higher levels of pRb in ESR1-YAP1 and ESR1-PCDH11x xenograft tumors and subsequent CDK4/6 inhibition completely blocked tumor growth in an ESR1-YAP1 PDX model. Integrating RNA-seq with ChIP-seq data, we discovered a set of EMT and metastasis genes bound by all ESR1 fusions and WT-ER, but whose expression was strongly and uniquely up-regulated only by the ESR1-YAP1 and ESR1-PCDH11x fusions. These studies also revealed gained sites bound only by the ESR1-YAP1 and ESR1-PCDH11x fusions, not bound by WT-ER nor ESR1-NOP2. Genes mapping to these sites have a role in metastatic biology and were highly up-regulated by the YAP1 and PCDH11x fusions, potentially mediated by long range transcriptional activation. Conclusion. ESR1-YAP1 and ESR1-PCDH11x are driver fusions that occur in drug-resistant, advanced stage breast cancer and are a new class of recurrent somatic mutation that can cause acquired endocrine therapy resistance, yet can be treated with CDK4/6 inhibition. These driver fusions also confer increased metastatic ability through their ability to drive expression of genes that contribute to EMT and metastasis. In contrast, ESR1-NOP2 did not produce functional protein and appears to be a passenger event. These studies may provide pre-clinical rationale for targeting ESR1 translocated breast tumors, since the presence of an ESR1 driver fusion places a patient in a therapeutic category where none of the currently available endocrine therapies are likely to be effective. Citation Format: Lei JT, Shao J, Zhang J, Iglesia M, Chan DW, Cao J, Anurag M, Singh P, Haricharan S, Kavuri SM, Matsunuma R, Schmidt C, Kosaka Y, Crowder R, Hoog J, Phommaly C, Goncalves R, Ramalho S, Rodrigues-Peres RM, Lai W-C, Hampton O, Rogers A, Tobias E, Parikh P, Davies S, Ma C, Suman V, Hunt K, Watson M, Hoadley KA, Thompson A, Perou CM, Creighton CJ, Maher C, Ellis MJ. ESR1 gene fusions drive endocrine therapy resistance and metastasis in breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD8-03.
Abstract 1033: Estrogen receptor gene fusions drive endocrine therapy resistance in estrogen receptor positive breast cancer
Shao, Jieya , Iglesia, Michael D. , Chan, Doug W. , Matsunuma, Ryoichi , He, Xiaping , Singh, Purba , Kosaka, Yoshimasa , Crowder, Robert J., Haricharan, Svasti , Kavuri, Shyam M. , Phommaly, Chanpheng, Gonçalves, Rodrigo , Romalho, Susana, Lai, W. Victoria , Rogers, Anna , Tobias, Ethan, Parikh, P.J., Cynthia, X. , Thompson, Aubrey, Creighton, Chad J. , Lei, Jonathan T. , Zhang, Jin , Hoog, Jeremy , Hampton, Oliver , Davies, Sherri R. , Suman, Vera J. , Hunt, Kelly K. , Watson, Mark A. , Hoadley, Katherine A. , Perou, Charles M. , Maher, Christopher G. , Ellis, Matthew J.

Cancer Research | July 31, 2017 | Volume: 77 | Issue: 13_Supplement | Pages: 1033-1033

10.1158/1538-7445.am2017-1033 Get It

Abstract Dysregulation of estrogen receptor gene (ESR1) is an established mechanism of inducing endocrine therapy resistance. We previously discovered a chromosomal translocation event generating an estrogen receptor gene fused in-frame to C-terminal sequences of YAP1 (ESR1-YAP1) that contributed to endocrine therapy resistance in estrogen receptor positive (ER+) breast cancer models. This current study compares functional and pharmacological properties of additional ESR1 gene fusion events of both early stage (ESR1-NOP2) and advanced endocrine therapy resistant (ESR1-YAP1 and ESR1-PCDH11x) breast cancers. The YAP1 and PCDH11x fusions conferred estrogen-independent and fulvestrant-resistant growth in T47D, an ER+ breast cancer cell line in vitro and in vivo, in contrast to the NOP2 fusion which was sensitive to hormone deprivation. Immunohistochemical (IHC) staining of mouse lungs revealed significantly higher numbers of micrometastatic ER+ cells from the T47D tumors expressing the YAP1 and PCDH11x fusions than YFP control and NOP2 fusion. Estrogen response element (ERE) reporter and pull down assays revealed that although all ESR1 fusions studied bound EREs, only the YAP1 and PCDH11x caused ERE activation. Cell lines containing these “canonical” ESR1 fusions upregulated expression of ER responsive genes such as TFF1 and GREB1 in hormone deprived conditions. In contrast, the NOP2 fusion neither induced ERE activity nor upregulated TFF1 and GREB1 gene expression. The proliferative ability of canonical fusion-containing T47D cells was inhibited by palbociclib, a CDK4/6 inhibitor, in a dose-dependent manner. In vivo growth of patient-derived xenograft tumors naturally harboring the ESR1-YAP1 fusion (WHIM18) was significantly reduced in mice fed palbociclib-containing chow. Mice transplanted with WHIM18 also formed lung micrometastases, with an ER IHC staining pattern similar to lungs from YAP1 and PCDH11x fusion expressing T47D xenografts. In conclusion, in-frame ERE activating canonical fusions occur in end-stage, drug resistant, advanced breast cancer and can be added to ESR1 point mutations as a class of somatic mutation that may cause acquired resistance. Endocrine therapy resistant growth induced by these fusions can be treated with CDK4/6 inhibition, using an FDA approved drug, palbociclib, which could potentially improve outcomes in patients with ESR1 translocated tumors. Citation Format: Jonathan T. Lei, Jieya Shao, Jin Zhang, Michael Iglesia, Doug W. Chan, Ryoichi Matsunuma, Xiaping He, Purba Singh, Yoshimasa Kosaka, Robert Crowder, Svasti Haricharan, Shyam Kavuri, Jeremy Hoog, Chanpheng Phommaly, Rodrigo Goncalves, Susana Romalho, Wei-Chu Lai, Oliver Hampton, Anna Rogers, Ethan Tobias, Poojan Parikh, Sherri Davies, Cynthia Ma, Vera Suman, Kelly Hunt, Mark Watson, Katherine A. Hoadley, Aubrey Thompson, Charles Perou, Chad J. Creighton, Chris Maher, Matthew J. Ellis. Estrogen receptor gene fusions drive endocrine therapy resistance in estrogen receptor positive breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1033. doi:10.1158/1538-7445.AM2017-1033
Abstract PD2-03: Recurrent functionally diverse in-frame ESR1 gene fusions drive endocrine resistance in breast cancer
Lei, JT, Shao, Juntao , Zhang, J, Iglesia, Michael D. , Cao, Jin , He, Xiaoping , Kosaka, Yoshimasa , Schmidt, Cecilia, Matsunuma, Ryoichi , Haricharan, Svasti , Crowder, RJ, Hoog, J, Phommaly, Chanpheng, Gonçalves, Rodrigo , Ramalho, Susana , Lai, W-C, Rogers, Anna , Tobias, Ethan, Parikh, Poojan A., Davies, S. J. , Hunt, Katie N. , Watson, Mark , Hoadley, KA, Thompson, Alastair M. , Chen, X , Perou, CM, Creighton, CJ, Maher, CA, Ellis, MJ, Maher, Christopher G. , Chan, David W. , Hampton, Oliver , Ma, C, Suman, Vera J. , Watson, M, Hoadley, Katherine A.

Cancer Research | March 1, 2017 | Volume: 77 | Issue: 4_Supplement | Pages: PD2-03-PD2-03

10.1158/1538-7445.sabcs16-pd2-03 Get It

Abstract Background. We previously reported an alternative ESR1 somatic gain-of-function chromosomal translocation event in a patient presenting with aggressive, endocrine therapy resistant estrogen receptor (ER) positive disease, producing an in-frame fusion gene consisting of N-terminal ESR1 and the C-terminus of the Hippo pathway coactivator YAP1 (ESR1-YAP1). We recently identified another ESR1 fusion through RNA sequencing (RNA-seq) in advanced stage ER+ disease from a chest wall recurrence in a male patient that was refractory to multiple lines of treatment. Two examples of fusions discovered in primary breast cancer samples include ESR1 fused in-frame to C-terminal sequences from NOP2 (ESR1-NOP2), identified in a resistant cohort from a RNA-seq screen focused on 81 primary breast cancers from aromatase inhibitor clinical trials, and a second ESR1 fusion, fused in-frame to the entire coding sequence of POLH (ESR1-POLH), that was identified from RNA-seq analysis of 728 Cancer Genome Atlas breast samples. This current study extends our previous characterization of ESR1-YAP1 by comparing functional and pharmacological properties of these three additional ESR1 gene fusion events of both early stage and advanced breast cancers. Methods. In vitro and in vivo experiments were conducted to test ESR1 fusions to induce therapeutic resistance, and metastasis. The transcriptional and binding properties of each fusion was also examined. Pharmacological inhibition with Palbociclib, a cyclin-dependent kinase 4/6 inhibitor, was utilized to assess drug sensitivity in ESR1 fusion containing breast cancer cells and in a patient derived xenograft (PDX) model expressing ESR1-YAP1 (WHIM18). Results. The YAP1 and PCDH11x fusions conferred estrogen-independent and fulvestrant-resistant growth. Immunohistochemistry revealed significantly higher numbers of ER+ cells in lungs of mice xenografted with T47D cells expressing the YAP1 and PCDH11x fusions compared to YFP control, NOP2 and POLH fusions. Results from ChIP-seq and microarray studies suggest that these two fusions promote proliferation and metastasis through genomic action by binding estrogen response elements (ERE) and subsequent gene activation. We thereby define these fusions as “canonical” fusions compared to “non-canonical” NOP2 and POLH fusions, which demonstrated dramatically decreased genomic binding ability. The non-canonical fusions induced genes associated with basal-like breast cancer and promoted HER2, EGFR, and MAPK gene expression signatures in contrast to genes associated with cell cycle/proliferation induced by canonical fusions. The proliferative ability of canonical fusion-containing ER+ cells was inhibited by Palbociclib in a dose-dependent manner. In vivo WHIM18 tumors in mice fed with Palbociclib-containing chow demonstrated significantly reduced tumor volume, growth rate, and weight compared to tumors in mice on control chow. Conclusions. In-frame ERE activating canonical fusions occur in end-stage drug resistant advanced breast cancer and can be added to ESR1 point mutations as a class of recurrent somatic mutation that may cause acquired resistance. Growth induced by these fusions can be antagonized by Palbociclib and is potentially clinically helpful. Citation Format: Lei JT, Shao J, Zhang J, Iglesia M, Cao J, Chan DW, He X, Kosaka Y, Schmidt C, Matsunuma R, Haricharan S, Crowder R, Hoog J, Phommaly C, Goncalves R, Ramalho S, Lai W-C, Hampton O, Rogers A, Tobias E, Parikh P, Davies S, Ma C, Suman V, Hunt K, Watson M, Hoadley KA, Thompson A, Chen X, Perou CM, Creighton CJ, Maher C, Ellis MJ. Recurrent functionally diverse in-frame ESR1 gene fusions drive endocrine resistance in breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD2-03.
A Phase I Study of the AKT Inhibitor MK-2206 in Combination with Hormonal Therapy in Postmenopausal Women with Estrogen Receptor–Positive Metastatic Breast Cancer
Cynthia, X. , Sánchez, César , Crowder, Robert J., Creekmore, Allison, Guo, Zhanfang , Doyle, Austin, Erlichman, Charles , Gao, Feng , Naughton, Michael J. , Pluard, Timothy , Hoog, Jeremy , Lockhart, A. Craig , Ellis, Matthew J. , Sánchez, César

Clinical Cancer Research | January 18, 2016 | Volume: 22 | Issue: 11 | Pages: 2650-2658

10.1158/1078-0432.ccr-15-2160 | PMID 26783290 Get It

Abstract Purpose: PI3K/AKT pathway activation is an important endocrine resistance mechanism in estrogen receptor–positive (ER+) breast cancer. After promising preclinical modeling of MK-2206, an allosteric pan-AKT inhibitor, with either estrogen deprivation or fulvestrant, we conducted a phase I trial in patients with metastatic ER+HER2− breast cancer to determine the recommended phase II treatment dose (RPTD) of MK-2206 when combined with either anastrozole, fulvestrant, or anastrozole/fulvestrant. Experimental Design: ER+ breast cancer cell lines were exposed in vitro to MK-2206 plus estrogen deprivation with or without fulvestrant and monitored for apoptosis. A standard 3+3 design was employed to first determine the maximum tolerated dose (MTD) of MK-2206 plus anastrozole based on cycle 1 toxicity. Each cycle was 28 days. The RPTD was determined on the basis of toxicities observed at MTD level during the first 3 cycles. Subsequent patients received MK-2206, at the RPTD determined above, plus fulvestrant or anastrozole/fulvestrant to define RPTD for these additional regimens. Results: MK-2206 induced apoptosis in parental ER+ but not in long-term estrogen-deprived cell lines, for which fulvestrant was required for apoptosis induction. Thirty-one patients enrolled. The RPTD was defined as MK-2206 150 mg orally weekly with prednisone prophylaxis for each combination. Grade 3 rash was dose limiting. 42% (95% CI, 23%–63%) patients derived clinical benefit without progression within 6 months. Response was not associated with tumor PIK3CA mutation. Conclusions: MK-2206 plus endocrine treatments were tolerable. MK-2206 in combination with anastrozole is being further evaluated in a phase II neoadjuvant trial for newly diagnosed ER+HER2− breast cancer. Clin Cancer Res; 22(11); 2650–8. ©2016 AACR. See related commentary by Jansen et al., p. 2599
Abstract PD6-4: ESR1 gene fusions implicated in endocrine therapy resistance of ER+ breast cancer
Shao, Jieya , Crowder, Robert J., Gonçalves, Rodrigo , Phommaly, Chanpheng, Network, Breast AWG and, Maher, Christopher A. , Thompson, E. Aubrey , Zhang, Jin , Network, Breast AWG and, Perou, Charles M. , Ellis, Matthew J.

Cancer Research | May 4, 2015 | Volume: 75 | Issue: 9_Supplement | Pages: PD6-4-PD6-4

10.1158/1538-7445.sabcs14-pd6-4 Get It

Abstract Background. We recently identified an in-frame ESR1 translocation in a tumor and PDX pair from a patient with endocrine therapy resistant advanced disease. The fusion gene preserved the N-terminal 365aa of ESR1 containing the intact activation function 1 (AF1), DNA-binding domain (DBD) and hinge, followed by the C-terminal transactivation domain of YAP1. The ESR1-365>YAP1 fusion drove estrogen-independent and anti-estrogen-resistant tumor cell growth (Cell Reports 4:1116, 2013). We therefore sought to further investigate the role of ESR1 fusion genes in breast cancer. Methods. 711 cases from TCGA, 82 ER+ cases from neoadjuvant endocrine therapy trials and 25 ER+ systemic relapse samples were screened for fusion genes using RNAseq. Fusion genes involving ESR1 were subsequently assayed for estrogen response element (ERE)-mediated transcriptional activity and ability to drive estradiol independent breast cancer cell growth. Results. Multiple ESR1 fusions were identified in mostly luminal B cancers. ESR1 fusions resulted most frequently from rearrangements involving another gene on Chromosome (Chr) 6 but also fusions with genes on other chromosomes. The fusions involving partners on Chr6 that retained an intact N terminal AF1 and DNA binding domain (DBD) of ESR1 (≥1-253aa) included an Out-of-Frame (OF) fusion event with CCDC170 (a gene immediately centromeric to ESR1), POLH (in-frame or IF), AKAP12 (IF), PCMT1 (OF), SYNE1 (OF) and GPR126 (OF). Also identified were inter-chromosomal translocations involving Chr12p-NOP2 (IF) and ChrX-PCDH11X (IF) and Chr7q-AKR1D1 (OF). The ESR1 fusions with transcriptional potential (because of a retained DNA binding domain) included variable 5’ ESR1 exons that preserved 253aa, 365aa, 412aa or 458aa of ESR1 sequence: in all cases disrupting ligand binding though loss of C terminal sequence. The effect of the IF and OF 3’ sequences on the transcriptional activity of the relevant ESR1 fragment was highly variable. The most transcriptionally active fusion (more active than the relevant ESR1 fragment alone) was the ESR1-365>YAP1 as well as ESR1-365>PCDH11X and ESR1-253>CCDC170. This is remarkable since PCDH11X is not considered a transcription factor and the CCDC170 sequence was OF – in both cases suggesting the activity of the fusion was due to "neomorphic" properties. Two fusions, NOP2 and POLH were inactive in the ERE reporter assay, yet both stimulated estradiol independent growth. In these cases we suggest that the ESR1 locus can function as a "promoter trap" which allows the identification of genes with previously unknown functions in endocrine therapy resistance. Conclusions: In luminal-type breast cancer the ESR1 gene was fused to multiple 3’ partners with remarkably heterogeneous functions. The two most transcriptionally active, ESR1-365>YAP1 and ESR1-365>PCDH11X, were both identified in endocrine therapy refractory advanced disease – suggesting a role in fatal disease progression. Citation Format: Jieya Shao, Jin Zhang, Robert J Crowder, Rodrigo Goncalves, Chanpheng Phommaly, Breast AWG and Network, Charles M Perou, Christopher A Maher, E Aubrey Thompson, Matthew J Ellis. ESR1 gene fusions implicated in endocrine therapy resistance of ER+ breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr PD6-4.