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Theresa Nguyen

Bio: Theresa Nguyen is an academic researcher from University of Texas MD Anderson Cancer Center. The author has contributed to research in topics: Sarcoma & Radiation therapy. The author has an hindex of 10, co-authored 15 publications receiving 644 citations. Previous affiliations of Theresa Nguyen include University of Texas Health Science Center at Houston.

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Journal ArticleDOI
27 Jan 2011-Oncogene
TL;DR: It is demonstrated that AKT1 activation induces STS cell motility and invasiveness at least partially through a novel interaction with the intermediate filament vimentin (Vim), which was shown to enhance tumor and metastasis growth in vivo.
Abstract: The PI3K/AKT signaling pathway is aberrant in a wide variety of cancers. Downstream effectors of AKT are involved in survival, growth and metabolic-related pathways. In contrast, contradictory data relating to AKT effects on cell motility and invasion, crucial prometastatic processes, have been reported pointing to a potential cell type and isoform type-specific AKT-driven function. By implication, study of AKT signaling should optimally be conducted in an appropriate intracellular environment. Prognosis in soft-tissue sarcoma (STS), the aggressive malignancies of mesenchymal origin, is poor, reflecting our modest ability to control metastasis, an effort hampered by lack of insight into molecular mechanisms driving STS progression and dissemination. We examined the impact of the cancer progression-relevant AKT pathway on the mesenchymal tumor cell internal milieu. We demonstrate that AKT1 activation induces STS cell motility and invasiveness at least partially through a novel interaction with the intermediate filament vimentin (Vim). The binding of AKT (tail region) to Vim (head region) results in Vim Ser39 phosphorylation enhancing the ability of Vim to induce motility and invasion while protecting Vim from caspase-induced proteolysis. Moreover, vimentin phosphorylation was shown to enhance tumor and metastasis growth in vivo. Insights into this mesenchymal-related molecular mechanism may facilitate the development of critically lacking therapeutic options for these devastating malignancies.

214 citations

Journal ArticleDOI
TL;DR: Proton beam therapy can be a safe and effective curative reirradiation strategy, with acceptable rates of toxicity and durable disease control.
Abstract: Purpose Reirradiation of head and neck (H&N) cancer is a clinical challenge. Proton radiation therapy (PRT) offers dosimetric advantages for normal tissue sparing and may benefit previously irradiated patients. Here, we report our initial experience with the use of PRT for H&N reirradiation, with focus on clinical outcomes and toxicity. Methods and Materials We retrospectively reviewed the records of patients who received H&N reirradiation with PRT from April 2011 through June 2015. Patients reirradiated with palliative intent or without prior documentation of H&N radiation therapy were excluded. Radiation-related toxicities were recorded according to the Common Terminology Criteria for Adverse Events Version 4.0. Results The conditions of 60 patients were evaluated, with a median follow-up time of 13.6 months. Fifteen patients (25%) received passive scatter proton therapy (PSPT), and 45 (75%) received intensity modulated proton therapy (IMPT). Thirty-five patients (58%) received upfront surgery, and 44 (73%) received concurrent chemotherapy. The 1-year rates of locoregional failure–free survival, overall survival, progression-free survival, and distant metastasis–free survival were 68.4%, 83.8%, 60.1%, and 74.9%, respectively. Eighteen patients (30%) experienced acute grade 3 (G3) toxicity, and 13 (22%) required a feeding tube at the end of PRT. The 1-year rates of late G3 toxicity and feeding tube independence were 16.7% and 2.0%, respectively. Three patients may have died of reirradiation-related effects (1 acute and 2 late). Conclusions Proton beam therapy can be a safe and effective curative reirradiation strategy, with acceptable rates of toxicity and durable disease control.

105 citations

Journal ArticleDOI
TL;DR: An important role is shown for MET in MPNST, supporting continued investigation of novel anti-MET therapies in this clinical context and Informative prognosticators and novel therapies are crucially needed to improve MPN ST management and outcomes.
Abstract: Purpose: MET signaling has been suggested a potential role in malignant peripheral nerve sheath tumors (MPNST). Here, MET function and blockade were preclinically assessed. Experimental Design: Expression levels of MET, its ligand hepatocyte growth factor (HGF), and phosphorylated MET (pMET) were examined in a clinically annotated MPNST tissue microarray (TMA) incorporating univariable and multivariable statistical analyses. Human MPNST cells were studied in vitro and in vivo ; Western blot (WB) and ELISA were used to evaluate MET and HGF expression, activation, and downstream signaling. Cell culture assays tested the impact of HGF-induced MET activation and anti-MET–specific siRNA inhibition on cell proliferation, migration, and invasion; in vivo gel-foam assays were used to evaluate angiogenesis. Cells stably transduced with anti-MET short hairpin RNA (shRNA) constructs were tested for growth and metastasis in severe combined immunodeficient (SCID) mice. The effect of the tyrosine kinase inhibitor XL184 (Exelixis) targeting MET/VEGFR2 (vascular endothelial growth factor receptor 2) on local and metastatic MPNST growth was examined in vivo . Results: All three markers were expressed in MPNST human samples; pMET expression was an independent prognosticator of poor patient outcome. Human MPNST cell lines expressed MET, HGF, and pMET. MET activation increased MPNST cell motility, invasion, angiogenesis, and induced matrix metalloproteinase-2 (MMP2) and VEGF expression; MET knockdown had inverse effects in vitro and markedly decreased local and metastatic growth in vivo . XL184 abrogated human MPNST xenograft growth and metastasis in SCID mice. Conclusions: Informative prognosticators and novel therapies are crucially needed to improve MPNST management and outcomes. We show an important role for MET in MPNST, supporting continued investigation of novel anti-MET therapies in this clinical context. Clin Cancer Res; 17(12); 3943–55. ©2011 AACR .

92 citations

Journal ArticleDOI
TL;DR: It is concluded that VEGF is a critical determinant of STS growth and metastasis and that STS chemoresistance, in this model, is a process induced by the interplay between STS cells and tumor-associated endothelial cells.
Abstract: To better elucidate the role of vascular endothelial growth factor (VEGF)(165) in soft tissue sarcoma (STS) growth, metastasis, and chemoresistance, we generated stably transfected human STS cell lines with VEGF(165) to study the effect of VEGF(165) on STS cells in vitro and the effect of culture medium from these cells on human umbilical vascular endothelial cells. Severe combined immunodeficient mice bearing xenografts of transfected cell lines were used to assess the effect of VEGF overexpression and the effect of VEGF receptor (VEGFR) 2 inhibition on STS growth, metastasis, and response to doxorubicin. VEGF(165)-transfected xenografts formed highly vascular tumors with shorter latency, accelerated growth, enhanced chemoresistance, and increased incidence of pulmonary metastases. Blockade of VEGFR2 signaling using DC101 anti-VEGFR2 monoclonal antibody enhanced doxorubicin chemoresponse; this combined biochemotherapy inhibited tumor growth and decreased pulmonary metastases without overt toxicity. Combined therapy reduced microvessel counts while increasing vessel maturation index. VEGF overexpression did not affect on the sarcoma cells per se; however, conditioned medium from VEGF transfectants caused increased endothelial cell proliferation, migration, and chemoresistance. Addition of DC101 induced endothelial cell sensitivity to doxorubicin and suppressed the activity of matrix metalloproteinases secreted by endothelial cells. We therefore conclude that VEGF is a critical determinant of STS growth and metastasis and that STS chemoresistance, in our model, is a process induced by the interplay between STS cells and tumor-associated endothelial cells. STS growth and metastasis can be interrupted by combined low-dose doxorubicin and anti-VEGFR2, a strategy that attacks STS-associated endothelial cells. In the future, such therapeutic approaches may be useful in treating STS before the development of clinically apparent metastases.

76 citations

Journal ArticleDOI
TL;DR: These newly established cellular and xenograft models can facilitate investigation of liposarcomagenesis, dedifferentiation, and tumor progression and may lead to improved therapeutic strategies for patients afflicted by these unfavorable malignancies.

70 citations


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TL;DR: By virtue of its overexpression in cancer and its association with tumor growth and metastasis, vimentin serves as an attractive potential target for cancer therapy; however, more research would be crucial to evaluate its specific role in cancer.
Abstract: Vimentin, a major constituent of the intermediate filament family of proteins, is ubiquitously expressed in normal mesenchymal cells and is known to maintain cellular integrity and provide resistance against stress. Vimentin is overexpressed in various epithelial cancers, including prostate cancer, gastrointestinal tumors, tumors of the central nervous system, breast cancer, malignant melanoma, and lung cancer. Vimentin’s overexpression in cancer correlates well with accelerated tumor growth, invasion, and poor prognosis; however, the role of vimentin in cancer progression remains obscure. In recent years, vimentin has been recognized as a marker for epithelial–mesenchymal transition (EMT). Although EMT is associated with several tumorigenic events, vimentin’s role in the underlying events mediating these processes remains unknown. By virtue of its overexpression in cancer and its association with tumor growth and metastasis, vimentin serves as an attractive potential target for cancer therapy; however, more research would be crucial to evaluate its specific role in cancer. Our recent discovery of a vimentin-binding mini-peptide has generated further impetus for vimentin-targeted tumor-specific therapy. Furthermore, research directed toward elucidating the role of vimentin in various signaling pathways would reveal new approaches for the development of therapeutic agents. This review summarizes the expression and functions of vimentin in various types of cancer and suggests some directions toward future cancer therapy utilizing vimentin as a potential molecular target.

1,185 citations

Journal ArticleDOI
TL;DR: A brief overview summarizes changes in the classification in each of the broad categories of soft tissue tumour (adipocytic, fibroblastic, etc.) and also provides a short summary of newer genetic data which have been incorporated in the WHO classification.
Abstract: The new World Health Organization (WHO) classification of soft tissue tumours was published in early 2013, almost 11 years after the previous edition. While the number of newly recognized entities included for the first time is fewer than that in 2002, there have instead been substantial steps forward in molecular genetic and cytogenetic characterization of this family of tumours, leading to more reproducible diagnosis, a more meaningful classification scheme and providing new insights regarding pathogenesis, which previously has been obscure in most of these lesions. This brief overview summarizes changes in the classification in each of the broad categories of soft tissue tumour (adipocytic, fibroblastic, etc.) and also provides a short summary of newer genetic data which have been incorporated in the WHO classification.

759 citations

Journal ArticleDOI
TL;DR: Pazopanib is well tolerated in patients with relapsed, advanced STS and demonstrates interesting activity that warrants additional study in patientswith leiomyosarcoma, synovial sarcomas, and other STS types.
Abstract: PURPOSE Given the importance of angiogenesis in soft tissue sarcoma (STS), pazopanib, an oral angiogenesis inhibitor that targets vascular endothelial growth factor receptor and platelet-derived growth factor receptor, was explored in patients with advanced STS. PATIENTS AND METHODS Patients with intermediate- or high-grade advanced STS who were ineligible for chemotherapy or who had received no more than two prior cytotoxic agents for advanced disease, who had documented progression, who had adequate performance status, and who had good organ function were eligible. Pazopanib 800 mg was given daily. The primary end point was progression-free rate at 12 weeks (PFR(12 weeks)). Secondary end points were response, safety, and overall survival. Four different strata were studied: adipocytic STS, leiomyosarcomas, synovial sarcomas, and other STS types. A Simon two-stage design was applied (P1 = 40%; P0 = 20%; alpha = beta = .1) for each stratum. Results One hundred forty-two patients were enrolled. The adipocytic STS stratum was closed after the first stage, given insufficient activity (PFR(12 weeks), five [26%] of19). PFR(12 weeks) was 18 (44%) of 41 patients in the leiomyosarcoma cohort, 18 (49%) of 37 in the synovial sarcomas, and 16 (39%) of 41 in the other STS types. Compared with historical controls who were treated with second-line chemotherapy, progression-free and overall survivals were prolonged in the three cohorts in which the primary end point was reached. The most frequent drug-related toxicities were hypertension, fatigue, hypopigmentation, and nausea. Other toxicities included liver enzyme elevations, myelosuppression, and proteinuria, all of which were mostly grades 1 to 2. The most frequent grades 3 to 4 toxicities were hyperbilirubinemia (6.3%), hypertension (7.7%), and fatigue (7.7%). CONCLUSION Pazopanib is well tolerated in patients with relapsed, advanced STS and demonstrates interesting activity that warrants additional study in patients with leiomyosarcomas, synovial sarcomas, and other STS types.

607 citations

Journal ArticleDOI
TL;DR: Proteomic advances highlight the enormous complexity and regulatory potential of IF protein PTMs, which include phosphorylation, glycosylation, sumoylation, acetylation and prenylations, with novel modifications becoming increasingly appreciated.
Abstract: Intermediate filaments (IFs) are cytoskeletal and nucleoskeletal structures that provide mechanical and stress-coping resilience to cells, contribute to subcellular and tissue-specific biological functions, and facilitate intracellular communication. IFs, including nuclear lamins and those in the cytoplasm (keratins, vimentin, desmin, neurofilaments and glial fibrillary acidic protein, among others), are functionally regulated by post-translational modifications (PTMs). Proteomic advances highlight the enormous complexity and regulatory potential of IF protein PTMs, which include phosphorylation, glycosylation, sumoylation, acetylation and prenylation, with novel modifications becoming increasingly appreciated. Future studies will need to characterize their on-off mechanisms, crosstalk and utility as biomarkers and targets for diseases involving the IF cytoskeleton.

417 citations

Journal ArticleDOI
TL;DR: The core molecular determinants of sarcomagenesis are discussed and the emerging genomic and functional genetic approaches that, coupled with novel therapeutic strategies, have the potential to transform the care of patients with sarcoma are emphasized.
Abstract: Increasingly, human mesenchymal malignancies are being classified by the abnormalities that drive their pathogenesis. Although many of these aberrations are highly prevalent within particular sarcoma subtypes, few are currently targeted therapeutically. Indeed, most subtypes of sarcoma are still treated with traditional therapeutic modalities, and in many cases sarcomas are resistant to adjuvant therapies. In this Review, we discuss the core molecular determinants of sarcomagenesis and emphasize the emerging genomic and functional genetic approaches that, coupled with novel therapeutic strategies, have the potential to transform the care of patients with sarcoma.

356 citations