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1.
Oncology (Williston Park) ; 34(8): 321-327, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32785929

RESUMO

Advances in immuno-oncology over the last several years have led to FDA approvals of novel agents. As our understanding of immune response and its checkpoints has evolved, further advances have been made in treatment for several cancer types. To predict a response to immunotherapy, the initial biomarkers used were expression of the PD-1 receptor and PD-L1, as assessed by immunohistochemistry. More recently, predictive biomarkers have included microsatellite instability, DNA mismatch repair, and tumor mutational burden. Although these markers may be clinically relevant in predicting an immunotherapy response, cancer immunotherapy fails some patients. Improved understanding of the human immune system is necessary, as is a careful evaluation of the methods used to predict and assess response to immuno-oncology treatments. With the application of therapeutic immune-modulating agents, more comprehensive assays, and associated bioinformatics tools to accurately assess the tumor microenvironment, we may better predict responses to immuno-oncology agents and the ever-increasing complexity of their clinical use.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Biomarcadores Tumorais/imunologia , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Humanos , Instabilidade de Microssatélites , Mutação , Neoplasias/metabolismo , Neoplasias/patologia , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo
2.
J Surg Oncol ; 113(3): 333-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26662660

RESUMO

For extremity soft tissue sarcomas, limb salvage is now standard of care. The extent of surgical margins is balanced with functionality of the resected limb. Although negative margins are the goal, the necessary width is unclear. Additional considerations for margin adequacy include presence of anatomic barriers such as fascia and periosteum, proximity of critical structures, receipt of adjuvant and neoadjuvant therapies, and histologic subtype. Multidisciplinary team discussion is critical for treatment planning.


Assuntos
Extremidades , Recidiva Local de Neoplasia/prevenção & controle , Sarcoma/prevenção & controle , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/prevenção & controle , Neoplasias de Tecidos Moles/cirurgia , Procedimentos Cirúrgicos Operatórios , Extremidades/patologia , Extremidades/cirurgia , Humanos , Salvamento de Membro , Terapia Neoadjuvante/métodos , Neoplasia Residual/prevenção & controle , Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Procedimentos Cirúrgicos Operatórios/métodos , Procedimentos Cirúrgicos Operatórios/normas
3.
BMC Cancer ; 15: 886, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26555296

RESUMO

BACKGROUND: USP18 (ubiquitin-specific protease 18) removes ubiquitin-like modifier interferon stimulated gene 15 (ISG15) from conjugated proteins. USP18 null mice in a FVB/N background develop tumors as early as 2 months of age. These tumors are leiomyosarcomas and thus represent a new murine model for this disease. METHODS: Heterozygous USP18 +/- FVB/N mice were bred to generate wild-type, heterozygous and homozygous cohorts. Tumors were characterized immunohistochemically and two cell lines were derived from independent tumors. Cell lines were karyotyped and their responses to restoration of USP18 activity assessed. Drug testing and tumorigenic assays were also performed. USP18 immunohistochemical staining in a large series of human leiomyosacomas was examined. RESULTS: USP18 -/- FVB/N mice spontaneously develop tumors predominantly on the back of the neck with most tumors evident between 6-12 months (80 % penetrance). Immunohistochemical characterization of the tumors confirmed they were leiomyosarcomas, which originate from smooth muscle. Restoration of USP18 activity in sarcoma-derived cell lines did not reduce anchorage dependent or independent growth or xenograft tumor formation demonstrating that these cells no longer require USP18 suppression for tumorigenesis. Karyotyping revealed that both tumor-derived cell lines were aneuploid with extra copies of chromosomes 3 and 15. Chromosome 15 contains the Myc locus and MYC is also amplified in human leiomyosarcomas. MYC protein levels were elevated in both murine leiomyosarcoma cell lines. Stabilized P53 protein was detected in a subset of these murine tumors, another feature of human leiomyosarcomas. Immunohistochemical analyses of USP18 in human leiomyosarcomas revealed a range of staining intensities with the highest USP18 expression in normal vascular smooth muscle. USP18 tissue array analysis of primary leiomyosarcomas from 89 patients with a clinical database revealed cases with reduced USP18 levels had a significantly decreased time to metastasis (P = 0.0441). CONCLUSIONS: USP18 null mice develop leiomyosarcoma recapitulating key features of clinical leiomyosarcomas and patients with reduced-USP18 tumor levels have an unfavorable outcome. USP18 null mice and the derived cell lines represent clinically-relevant models of leiomyosarcoma and can provide insights into both leiomyosarcoma biology and therapy.


Assuntos
Carcinogênese/genética , Leiomiossarcoma/genética , Ubiquitina Tiolesterase/genética , Neoplasias Uterinas/genética , Animais , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Leiomiossarcoma/patologia , Camundongos , Camundongos Knockout , Metástase Neoplásica , Proteína Supressora de Tumor p53/genética , Ubiquitina Tiolesterase/biossíntese , Neoplasias Uterinas/patologia
4.
Curr Oncol Rep ; 17(8): 39, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26092408

RESUMO

Management of retroperitoneal soft tissue sarcomas (RP STS) can be very challenging. In contrast to the more common extremity STS, the two predominant histologic subtypes encountered in the retroperitoneum are well-differentiated/dedifferentiated liposarcoma and leiomyosarcoma. Surgery remains the mainstay of treatment for RP STS. Preoperative planning and anticipation of the need for resection of adjacent organs/structures are critical. The extent of surgery, including the role of compartmental resection, is still controversial. Radiation therapy may be an important adjunct to surgery to provide locoregional disease control; this is currently being evaluated in the preoperative setting in the EORTC STRASS trial. Systemic therapy, tailored to the specific histologic subtype, may also be of benefit for the management of RP STS. Further investigation of novel therapies (e.g., targeted therapies, immunotherapy) is needed. Overall, multi-institutional collaboration is important moving forward, to continue to better understand and optimize management of this disease.


Assuntos
Neoplasias Retroperitoneais/terapia , Sarcoma/terapia , Antineoplásicos/uso terapêutico , Humanos , Imunoterapia/métodos , Terapia de Alvo Molecular/métodos , Planejamento de Assistência ao Paciente , Radioterapia Adjuvante/métodos
5.
BMC Clin Pathol ; 14: 42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25349530

RESUMO

BACKGROUND: Liposarcoma (LS) is the second-most common type of soft-tissue sarcoma. Despite advances in knowledge and treatment of this disease, there remains a need for more effective LS therapy. Steroid hormone receptors regulate metabolism in adipocytes. Estrogen receptor alpha (ER), progesterone receptor (PR), and androgen receptor (AR) have been implicated in the pathophysiology of other cancer types. We sought to comprehensively determine temporal expression patterns of these receptors in LS. METHODS: We analyzed 561 histologically subtyped LS specimens from 354 patients for expression of ER, PR, and AR by immunohistochemistry (IHC) using diagnostic-grade reagents and protocols. The fractions of positively stained tumor cells were scored within each specimen. IHC scores were compared across LS subtypes using the Kruskal-Wallis test, and subtypes were compared using Dunn's post-hoc test. Ages of patients with receptor-positive vs. -negative LS were compared by t-test. Genders and races were compared for hormone receptor positivity using Fisher's exact test and Chi-square analysis, respectively. Recurrence-free survival was compared between receptor-positive and negative patients by log-rank test. p< 0.05 was considered significant. RESULTS: ER and AR were frequently expressed in LS, while few tumors expressed PR. Most of the ER + and AR + samples were of the well-differentiated LS subtype. A smaller fraction of de-differentiated LS expressed ER or AR, but expression was common within well-differentiated regions of tumors histologically classified as de-differentiated LS. In LS specimens from patients who underwent multiple surgeries over time, receptor expression frequently changed over time, which may be attributable in part to intratumor heterogeneity, varying degrees of de-differentiation, and biopsy bias. ER and AR were frequently co-expressed. Receptor status was not significantly associated with gender or race, but AR and PR expression were associated with earlier age at diagnosis. Receptor expression was not associated with altered recurrence-free survival. CONCLUSIONS: ER and AR are commonly expressed in LS, particularly in well-differentiated tumors. These data warrant further functional study to determine receptor function in LS, and the potential efficacy of anti-hormone therapies for the treatment of patients with LS.

6.
Breast Cancer Res Treat ; 138(1): 175-83, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23417336

RESUMO

Conjugated linoleic acid (CLA) is widely used as a "nutraceutical" for weight loss. CLA has anticancer effects in preclinical models, and we demonstrated in vitro that this can be attributed to the suppression of fatty acid (FA) synthesis. We tested the hypothesis that administration of CLA to breast cancer patients would inhibit expression of markers related to FA synthesis in tumor tissue, and that this would suppress tumor proliferation. Women with Stage I-III breast cancer were enrolled into an open label study and treated with CLA (1:1 mix of 9c,11t- and 10t,12c-CLA isomers, 7.5 g/d) for ≥ 10 days before surgery. Fasting plasma CLA concentrations measured pre- and post-CLA administration, and pre/post CLA tumor samples were examined by immunohistochemistry for Spot 14 (S14), a regulator of FA synthesis, FA synthase (FASN), an enzyme of FA synthesis, and lipoprotein lipase (LPL), the enzyme that allows FA uptake. Tumors were also analyzed for expression of Ki-67 and cleaved caspase 3. 24 women completed study treatment, and 23 tumors were evaluable for the primary endpoint. The median duration of CLA therapy was 12 days, and no significant toxicity was observed. S14 expression scores decreased (p = 0.003) after CLA administration. No significant change in FASN or LPL expression was observed. Ki-67 scores declined (p = 0.029), while cleaved caspase 3 staining was unaffected. Decrements in S14 or Ki-67 did not correlate with fasting plasma CLA concentrations at surgery. Breast tumor tissue expression of S14, but not FASN or LPL, was decreased after a short course of treatment with 7.5 g/day CLA. This was accompanied by reductions in the proliferation index. CLA consumption was well-tolerated and safe at this dose for up to 20 days. Overall, CLA may be a prototype compound to target fatty acid synthesis in breast cancers with a "lipogenic phenotype".


Assuntos
Vias Biossintéticas/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Ácido Linoleico/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Humanos , Ácido Linoleico/administração & dosagem , Ácido Linoleico/efeitos adversos , Pessoa de Meia-Idade , Gradação de Tumores
7.
Ann Surg Oncol ; 19(4): 1074-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22203182

RESUMO

BACKGROUND: Imatinib inhibits the KIT and PDGFR tyrosine kinases, resulting in its notable antitumor activity in gastrointestinal stromal tumor (GIST). We previously reported the early results of a multi-institutional prospective trial (RTOG 0132) using neoadjuvant/adjuvant imatinib either in primary resectable GIST or as a planned preoperative cytoreduction agent for metastatic/recurrent GIST. METHODS.: Patients with primary GIST (≥5 cm, group A) or resectable metastatic/recurrent GIST (≥2 cm, group B) received neoadjuvant imatinib (600 mg/day) for approximately 2 months and maintenance postoperative imatinib for 2 years. We have now updated the clinical outcomes including progression-free survival, disease-specific survival, and overall survival at a median follow-up of 5.1 years, and we correlate these end points with duration of imatinib therapy. RESULTS: Sixty-three patients were originally entered (53 analyzable: 31 in group A and 22 in group B). Estimated 5-year progression-free survival and overall survival were 57% in group A, 30% in group B; and 77% in group A, 68% in group B, respectively. Median time to progression has not been reached for group A and was 4.4 years for group B. In group A, in 7 of 11 patients, disease progressed >2 years from registration; 6 of 7 patients with progression had stopped imatinib before progression. In group B, disease progressed in 10 of 13 patients>2 years from registration; 6 of 10 patients with progressing disease had stopped imatinib before progression. There was no significant increase in toxicity compared with our previous short-term analysis. CONCLUSIONS: This long-term analysis suggests a high percentage of patients experienced disease progression after discontinuation of 2-year maintenance imatinib therapy after surgery. Consideration should be given to studying longer treatment durations in intermediate- to high-risk GIST patients.


Assuntos
Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/secundário , Recidiva Local de Neoplasia/tratamento farmacológico , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzamidas , Quimioterapia Adjuvante , Progressão da Doença , Intervalo Livre de Doença , Feminino , Seguimentos , Tumores do Estroma Gastrointestinal/mortalidade , Humanos , Mesilato de Imatinib , Masculino , Pessoa de Meia-Idade , Piperazinas/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/efeitos adversos , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
8.
Cancers (Basel) ; 14(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35326655

RESUMO

Invasive melanoma is the deadliest type of skin cancer, with 101,110 expected cases to be diagnosed in 2021. Recurrent BRAF and NRAS mutations are well documented in melanoma. Biologic implications of gene fusions and the efficacy of therapeutically targeting them remains unknown. Retrospective review of patient samples that underwent next-generation sequencing of the exons of 592 cancer-relevant genes and whole transcriptome sequencing for the detection of gene fusion events and gene expression profiling. Expression of PDL1 and ERK1/2 was assessed by immunohistochemistry (IHC). There were 33 (2.6%) cases with oncogenic fusions (14 novel), involving BRAF, RAF1, PRKCA, TERT, AXL, and FGFR3. MAPK pathway-associated genes were over-expressed in BRAF and RAF1 fusion-positive tumors in absence of other driver alterations. Increased expression in tumors with PRKCA and TERT fusions was concurrent with MAPK pathway alterations. For a subset of samples with available tissue, increased phosphorylation of ERK1/2 was observed in BRAF, RAF1, and PRKCA fusion-positive tumors. Oncogenic gene fusions are associated with transcriptional activation of the MAPK pathway, suggesting they could be therapeutic targets with available inhibitors. Additional analyses to fully characterize the oncogenic effects of these fusions may support biomarker driven clinical trials.

9.
Int J Cancer ; 129(11): 2533-42, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21671474

RESUMO

Although surgery remains the mainstay for the treatment of primary gastrointestinal stromal tumors (GIST), a significant number of patients experience disease recurrence within 5 years of surgery. The emergence of imatinib therapy for the treatment of patients with advanced GIST has offered unprecedented improvements in clinical outcomes for these patients. Prospective clinical trials have supported the efficacy and safety of imatinib before and after surgical resection of GIST. The American College of Surgeons Oncology Group Z9001 pivotal trial revealed that 1 year of adjuvant imatinib therapy provides significantly superior recurrence-free survival in patients with GIST after surgical resection, when compared to placebo. Additional trials and case studies have also begun to define the potential clinical benefit of imatinib in the neoadjuvant setting. Optimized risk stratification paradigms will be required to ensure the appropriate selection of patients to undergo treatment with imatinib in these settings. Risk stratification schemes are evolving that potentially will include mutation status and tumor rupture, and predictive nomograms have recently been proposed. The recent European Society of Medical Oncology and National Comprehensive Cancer Network guidelines mention use of adjuvant imatinib for ≥ 1 year in patients with KIT(+) , resectable GIST at high risk of recurrence. Moreover, the guidelines support the use of neoadjuvant imatinib in cases of limited disease if it would facilitate less extensive surgery and organ sparing. This article reviews pivotal efficacy and safety data for adjuvant imatinib and explores the potential clinical benefit of neoadjuvant imatinib in patients with GIST.


Assuntos
Antineoplásicos/uso terapêutico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Terapia Neoadjuvante , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Benzamidas , Quimioterapia Adjuvante , Gerenciamento Clínico , Humanos , Mesilato de Imatinib
10.
Surgery ; 169(1): 138-144, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32709489

RESUMO

BACKGROUND: At presentation, 21% to 49% of patients with adrenocortical cancer have metastases. Standard chemotherapy has a 23% response rate. We assessed whether next generation sequencing could elucidate additional treatment options in refractory adrenocortical cancer. METHODS: Retrospective analysis using a commercial, 592-gene DNA-based panel was performed of next generation sequencing data from 94 adrenocortical cancer tumors profiled for clinical care. We compared our data to the adrenocortical cancer database of The Cancer Genome Atlas containing survival data. We evaluated mutations, indels, amplifications, tumor mutation burden, microsatellite instability, and programmed death-ligand 1 protein expression. RESULTS: Our cohort included 54 primary neoplasms and 40 metastatic lesions. The most frequently mutated genes were TP53 (36%) and CTNNB1 (19%). Low prevalence mutations were noted in 37 genes including DNA damage repair genes in 15 samples. High tumor mutation burden was seen in 3 patients, and programmed death-ligand 1 was positive in 12. Potential targets to Food and Drug Administration-approved drugs were seen in 16% of cases. CONCLUSION: DNA sequencing panel tests may identify therapeutic options for some patients with adrenocortical cancer. TP53 and mutations were associated with an adverse outcome. An expanded repertoire of drugs and, perhaps, more expansive multi-omic sequencing are needed to advance the treatment of adrenocortical cancer.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Adolescente , Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/patologia , Adulto , Idoso , Antineoplásicos/farmacologia , Biomarcadores Tumorais/antagonistas & inibidores , Criança , Reparo do DNA/genética , Conjuntos de Dados como Assunto , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Amplificação de Genes , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Medicina de Precisão/métodos , Estudos Retrospectivos , Análise de Sequência de DNA , Proteína Supressora de Tumor p53/genética , Adulto Jovem , beta Catenina/genética
11.
Genes Chromosomes Cancer ; 48(10): 886-96, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19585585

RESUMO

Gastrointestinal stromal tumors (GISTs) generally harbor activating mutations in KIT or platelet-derived growth facter receptor (PDGFRA). Mutations in these receptor tyrosine kinases lead to dysregulation of downstream signaling pathways that contribute to GIST pathogenesis. GISTs with KIT or PDGFRA mutations also undergo secondary cytogenetic alterations that may indicate the involvement of additional genes important in tumor progression. Approximately 10-15% of adult and 85% of pediatric GISTs do not have mutations in KIT or in PDGFRA. Most mutant adult GISTs display large-scale genomic alterations, but little is known about the mutation-negative tumors. Using genome-wide DNA arrays, we investigated genomic imbalances in a set of 31 GISTs, including 10 KIT/PDGFRA mutation-negative tumors from nine adults and one pediatric case and 21 mutant tumors. Although all 21 mutant GISTs exhibited multiple copy number aberrations, notably losses, eight of the 10 KIT/PDGFRA mutation-negative GISTs exhibited few or no genomic alterations. One KIT/PDGFRA mutation-negative tumor exhibiting numerous genomic changes was found to harbor an alternate activating mutation, in the serine-threonine kinase BRAF. The only other mutation-negative GIST with significant chromosomal imbalances was a recurrent metastatic tumor found to harbor a homozygous deletion in chromosome arm 9p. Similar findings in several KIT-mutant GISTs identified a minimal overlapping region of deletion of approximately 0.28 Mbp in 9p21.3 that includes only the CDKN2A/2B genes, which encode inhibitors of cell-cycle kinases. These results suggest that GISTs without activating kinase mutations, whether pediatric or adult, generally exhibit a much lower level of cytogenetic progression than that observed in mutant GISTs.


Assuntos
Tumores do Estroma Gastrointestinal/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Tumores do Estroma Gastrointestinal/enzimologia , Dosagem de Genes , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética
12.
Oral Oncol ; 111: 104899, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32665184

RESUMO

The current standard of care for cutaneous melanoma of the ear is surgical excision. This approach may result in unfavorable functional and cosmetic outcomes. We report here a case of recurrent melanoma of the ear that achieved complete response with talimogene laherparepvec treatment after the patient declined surgical resection.


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Produtos Biológicos/administração & dosagem , Pavilhão Auricular , Neoplasias da Orelha/tratamento farmacológico , Melanoma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Pavilhão Auricular/patologia , Neoplasias da Orelha/patologia , Neoplasias da Orelha/cirurgia , Herpesvirus Humano 1 , Humanos , Injeções Intralesionais , Masculino , Melanoma/patologia , Melanoma/cirurgia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia
13.
Nutr Cancer ; 61(1): 114-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19116881

RESUMO

Spot 14 (THRSP, S14) is a nuclear protein involved in the regulation of genes required for fatty acid synthesis in normal and malignant mammary epithelial and adipose cells. Harvatine and Bauman (1) reported that conjugated linoleic acid (CLA) inhibits S14 gene expression in bovine mammary and mouse adipose tissues and reduces milk fat production in cows. We hypothesized that CLA inhibits S14 gene expression in human breast cancer and liposarcoma cells and that this will retard their growth. Exposure of T47D breast cancer cells to a mixture of CLA isomers reduced the expression of the S14 and fatty acid synthase (FAS) genes. The mixture caused a dose-related inhibition of T47D cell growth, as did pure c9, t11 and t10, c12-CLA, but not linoleic acid. Similar effects were observed in MDA-MB-231 breast cancer cells. Provision of 8 mircoM palmitate fully (CLA mix, t10, c12-CLA) or partially (c9, t11-CLA) reversed the antiproliferative effect in T47D cells. CLA likewise suppressed levels of S14 and FAS mRNAs in liposarcoma cells and caused growth inhibition that was prevented by palmitic acid. CLA did not affect the growth of nonlipogenic HeLa cells or human fibroblasts. We conclude that as in bovine mammary and mouse adipose cells, CLA suppresses S14 and FAS gene expression in human breast cancer and liposarcoma cells. Rescue from the antiproliferative effect of CLA by palmitic acid indicates that reduced tumor lipogenesis is a major mechanism for the anticancer effects of CLA.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Ácido Graxo Sintases/antagonistas & inibidores , Inibidores do Crescimento/farmacologia , Ácidos Linoleicos Conjugados/farmacologia , Lipossarcoma/tratamento farmacológico , Proteínas Nucleares/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lipossarcoma/metabolismo , Lipossarcoma/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas
14.
J Surg Oncol ; 99(1): 42-7, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18942073

RESUMO

BACKGROUND: Therapy for gastrointestinal stromal tumors (GIST) has changed significantly with the use of imatinib mesylate (IM). Despite the success of this drug in metastatic GIST, disease progression remains a perplexing clinical issue suggesting the need for multimodality management. There have been no prospective studies either evaluating the neoadjuvant use of IM in primary GIST or as a preoperative cytoreduction agent for metastatic GIST. METHODS: RTOG 0132/ACRIN 6665 was a prospective phase II study evaluating safety and efficacy of neoadjuvant IM (600 mg/day) for patients with primary GIST or the preop use of IM in patients with operable metastatic GIST. The trial continued postop IM for 2 years. RESULTS: Sixty-three patients were entered (52 analyzable), 30 patients with primary GIST (Group A) and 22 with recurrent metastatic GIST (Group B). Response (RECIST) in Group A was (7% partial, 83% stable, 10% unknown), in Group B (4.5% partial, 91% stable, 4.5% progression). Two-year progression free survival (Group A 83%, Group B 77%). Estimated overall survival (Group A 93%, Group B 91%). Complications of surgery and IM toxicity were minimal. CONCLUSION: This trial represents the first prospective report of preop IM in GIST. This approach is feasible, requires multidisciplinary consultations, and is not associated with notable postop complications.


Assuntos
Antineoplásicos/administração & dosagem , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Benzamidas , Terapia Combinada , Feminino , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/secundário , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Mesilato de Imatinib , Masculino , Pessoa de Meia-Idade , Piperazinas/efeitos adversos , Estudos Prospectivos , Pirimidinas/efeitos adversos , Análise de Sobrevida , Resultado do Tratamento
15.
Cancer Invest ; 26(2): 118-27, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18259941

RESUMO

Liposarcomas constitute a rare group of tumors of mesenchymal origin that are often poorly responsive to therapy. This study characterizes a novel human liposarcoma cell line (LiSa-2) and defines the mechanism of its response to a synthetic triterpenoid. Fatty acid synthase (FAS) is a key enzyme of de-novo fatty acid synthesis and is highly expressed in both human liposarcoma tissue specimens and LiSa-2 cells. Treatment of the LiSa-2 cell line with the synthetic triterpenoid 2-cyano-3,12-dioxooleana-1,9-dien-28-oic imidazolide (CDDO-Im) markedly inhibited FAS mRNA expression, FAS protein production and FAS gene promoter activity. As expected, fatty acid synthesis was down regulated, but there was no effect on cellular fatty acid uptake or glycerol-3-phosphate synthesis suggesting a selective inhibition of endogenous fatty acid synthesis. Importantly, CDDO-Im produced a dose-dependent apoptotic effect in the LiSa-2 cell line, and simultaneous treatment with CDDO-Im and the fatty acid synthase inhibitor Cerulenin produced a synergistic cytotoxic effect. Thus, CDDO-Im and Cerulenin act at different loci to inhibit long chain fatty acid synthesis in liposarcoma cells. This study's demonstration of CDDO-Im inhibition of FAS and Spot 14 (S14) expression is the first report of triterpenoid compounds affecting the fatty acid synthesis pathway. The observed dependence of liposarcomas on lipogenesis to support their growth and survival provides a novel approach to the treatment of liposarcomas with agents that target fatty acid production.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ácido Graxo Sintases/antagonistas & inibidores , Imidazóis/farmacologia , Lipossarcoma/tratamento farmacológico , Ácido Oleanólico/análogos & derivados , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Western Blotting , Cerulenina/farmacologia , Sinergismo Farmacológico , Quimioterapia Combinada , Inibidores da Síntese de Ácidos Graxos/farmacologia , Glicerolfosfato Desidrogenase/metabolismo , Humanos , Ácido Oleanólico/farmacologia , Ácido Palmítico/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Receptor fas/genética , Receptor fas/metabolismo
16.
Semin Oncol ; 33(6 Suppl 11): S75-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17178293

RESUMO

Gastrointestinal stromal tumor (GIST) is the most common nonepithelial tumor of the gastrointestinal tract. The majority of these tumors stain positive for the CD117 antigen to the KIT protein and have become a well-documented clinical entity. The dysregulated KIT protein is oncogenic and is an ideal target for imatinib, a KIT-selective inhibitor. Clinical trials of imatinib for metastatic GIST have shown either partial response or long-duration stable disease in 82% of patients. Trials addressing the efficacy of adjuvant imatinib following resection for high-risk primary GIST are awaiting results. The neoadjuvant preoperative use of imatinib to provide pharmacologic debulking and long-term disease control is also nearing completion in a clinical trial. This trial has the potential of addressing whether the combination of surgery and imatinib can enhance organ sparing, decrease drug resistance, and prolong disease-free and overall survival. The continued study of combining surgery and a target-specific agent for malignant GIST will be a valuable reference for future strategies combining surgery and targeted treatment in other solid tumors.


Assuntos
Tumores do Estroma Gastrointestinal/terapia , Terapia Combinada , Humanos
17.
Clin Colorectal Cancer ; 6 Suppl 1: S24-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17101065

RESUMO

Gastrointestinal stromal tumor (GIST) has become a well-recognized pathologic entity defined by expression of the KIT protein and often associated with gain of function mutations of the c-KIT oncogene. Imatinib, a specific inhibitor of the aberrant KIT protein, is an approved, well-tolerated oral drug for the management of metastatic or inoperable GIST. Traditional radical surgery resection for locally advanced, recurrent, or metastatic GIST is associated with a poor outcome. The rationale for combining imatinib with surgery for GIST, either as an adjuvant agent in the situation of primary resection for patients at high risk or in the neoadjuvant setting for patients with locally advanced, recurrent, or metastatic disease, is compelling in the continuous effort to improve disease-free and overall survival. Several clinical trials are addressing these issues as well as timing of surgery, assessment of drug response, and the addition of surgical resection in the situation of focal progressive disease on imatinib. The results of these studies will be meaningful in future standard therapy consideration.


Assuntos
Antineoplásicos/uso terapêutico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/cirurgia , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Benzamidas , Ensaios Clínicos como Assunto , Terapia Combinada , Tumores do Estroma Gastrointestinal/patologia , Humanos , Mesilato de Imatinib , Terapia Neoadjuvante , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X
18.
Cancer Res ; 64(18): 6476-81, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15374957

RESUMO

Because existing surgical and management methods can consistently cure only early-stage ovarian cancer, novel strategies for early detection are required. Silencing of tumor suppressor genes such as p16INK4a, VHL, and hMLH1 have established promoter hypermethylation as a common mechanism for tumor suppressor inactivation in human cancer and as a promising target for molecular detection in bodily fluids. Using sensitive methylation-specific PCR, we screened matched tumor, preoperative serum or plasma, and peritoneal fluid (washes or ascites) DNA obtained from 50 patients with ovarian or primary peritoneal tumors for hypermethylation status of the normally unmethylated BRCA1 and RAS association domain family protein 1A tumor suppressor genes. Hypermethylation of one or both genes was found in 34 tumor DNA (68%). Additional examination of one or more of the adenomatous polyposis coli, p14ARF, p16INK4a, or death associated protein-kinase tumor suppressor genes revealed hypermethylation in each of the remaining 16 tumor DNA, which extended diagnostic coverage to 100%. Hypermethylation was observed in all histologic cell types, grades, and stages of ovarian tumor examined. An identical pattern of gene hypermethylation was found in the matched serum DNA from 41 of 50 patients (82% sensitivity), including 13 of 17 cases of stage I disease. Hypermethylation was detected in 28 of 30 peritoneal fluid DNA from stage IC-IV patients, including 3 cases with negative or atypical cytology. In contrast, no hypermethylation was observed in nonneoplastic tissue, peritoneal fluid, or serum from 40 control women (100% specificity). We conclude that promoter hypermethylation is a common and relatively early event in ovarian tumorigenesis that can be detected in the serum DNA from patients with ovary-confined (stage IA or B) tumors and in cytologically negative peritoneal fluid. Analysis of tumor-specific hypermethylation in serum DNA may enhance early detection of ovarian cancer.


Assuntos
Metilação de DNA , Genes BRCA1 , Neoplasias Ovarianas/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Líquido Ascítico/genética , Líquido Ascítico/metabolismo , DNA de Neoplasias/sangue , DNA de Neoplasias/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue
19.
Am J Surg ; 189(5): 606-9; discussion 609, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15862505

RESUMO

INTRODUCTION: The purpose of this study was to better characterize the clinical significance of cytokeratin immunohistochemistry (IHC)-only-positive lymph node metastases among patients with breast cancer. METHODS: We performed a retrospective review of 334 patients who underwent sentinel lymph node (SLN) biopsy from 1 February 1997 through 31 July 2001. SLN biopsies were evaluated using standard hematoxylin and eosin (H&E) techniques. If H&E was negative, cytokeratin IHC was performed. We then evaluated the incidence of subsequent regional and distant metastatic disease. RESULTS: Cytokeratin IHC was performed on 183 sentinel node biopsies from 180 patients comprising a total of 427 sentinel lymph nodes. The procedures included lumpectomy and SLN biopsy (n = 83), mastectomy with SLN biopsy (n = 7), lumpectomy with SLN biopsy and completion axillary dissection (n = 80), and modified radical mastectomy with SLN biopsy and completion axillary dissection (n = 13). Cytokeratin IHC was negative in 175 axillary specimens and positive in 8 (4.4%) from 8 different patients. In these eight specimens, deeper sections with subsequent H&E staining additionally identified micrometastasis in four patients. Three of these 8 patients (37.5%) developed distant metastatic disease compared with 1 of the 172 patients (0.6%) with negative cytokeratin IHC (P < .001). Additionally, one of the cytokeratin-positive patients developed regional nodal metastasis compared with none of the 172 cytokeratin-negative patients. CONCLUSIONS: Cytokeratin IHC provides a clinically relevant adjunct to H&E staining for evaluating sentinel lymph nodes in breast cancer. These data suggest that patients with cytokeratin-positive sentinel nodes are at increased risk for development of regional and distant metastatic disease.


Assuntos
Neoplasias da Mama/patologia , Queratinas/análise , Metástase Linfática/patologia , Estadiamento de Neoplasias/métodos , Biópsia de Linfonodo Sentinela , Humanos , Imuno-Histoquímica , Estudos Retrospectivos
20.
Clin Cancer Res ; 9(6): 1941-56, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12796356

RESUMO

Sarcomas--like leukemias, which are also mesodermal malignancies--carry biological significance disproportionate to their clinical frequency. Identification of mutations and translocations associated with these tumors has illuminated aberrant signaling pathways that cause these diseases, determine their behavior, and are therapeutic targets. Activated receptor-associated tyrosine kinase c-kit, mutated in most gastrointestinal stromal tumors, has proven a clinically effective target for enzyme inhibition. A translocation involving a single gene family, consisting of EWS and related genes, has been identified in five different sarcomas, and its chimeric protein products could prove similarly amenable to inhibitors. Resolution of the histopathological complexity is being aided by data from molecular and chromosomal characterization. Improvements in imaging, definition of prognostic factors, and surgical and radiotherapeutic treatment have resulted in improved local control. Continued progress will depend on further adapting the rapidly evolving technologies of genomics and proteomics. It will also depend upon accurate histopathological diagnosis based on validated reagents and consistent methodologies applied to adequate tissue samples derived from patients with complete clinical data. Finally, multicenter, coordinated trials, such as those that occurred with assessment of imatinib mesylate in metastatic gastrointestinal stromal tumors, will assure the most rapid reductions in morbidity and mortality.


Assuntos
Sarcoma/terapia , Adulto , Quimioterapia Adjuvante , Aberrações Cromossômicas , Humanos , Cariotipagem , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Retroperitoneais/terapia , Sarcoma/genética , Sarcoma/patologia
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