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1.
Cureus ; 15(11): e48759, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38024013

RESUMO

Liposarcomas are extremely rare occurrences in the esophagus. Here, we present an unusual case of esophageal liposarcoma that contributed to a long history of dysphagia before a definitive diagnosis was reached. The case is that of a 61-year-old woman who complained of dysphagia and foreign body sensation in her throat and was found to have a large filling defect within the cervical esophagus on barium esophagogram. She underwent endoscopic resection of the mass and was diagnosed with a five-centimeter long, well-differentiated esophageal liposarcoma, confirmed with fluorescence in situ hybridization for MDM2 gene locus amplification. Subsequent laser ablation of the tumor bed was conducted with no recurrences noted to date. Proper histologic identification, alongside adjunctive cytogenetic and molecular diagnostics, followed by definitive surgical resection and extended follow-up, are emphasized as critical in optimizing outcomes for this disease. A review of the existing English-language medical literature relating to esophageal liposarcoma was performed and summarized.

2.
Gynecol Oncol Rep ; 47: 101204, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37304973

RESUMO

Vulvar angiomyxomas are rare benign mesenchymal neoplasms. Superficial and Aggressive angiomyxomas are two distinct phenotypes that present similarly to other more common vulva-perineal pathologies. Albeit both angiomyxomas carry a risk of recurrence, especially in the setting of incomplete resection, simple excision is insufficient for Aggressive angiomyxoma. It requires wide local excision because of its unique potential for local invasion, infiltration of the paravaginal and pararectal tissue, and more distant metastasis. Here, we present a case of Superficial angiomyxoma and a case of Aggressive angiomyxoma to highlight the diagnostic challenges and management strategies of each tumor. In both cases, angiomyxomas were initially misdiagnosed because of their rarity and nonspecific presentation. Magnetic resonance imaging is the modality of choice for evaluation due to inherent higher spatial resolution of soft tissue anatomical details. Early diagnosis of Aggressive angiomyxoma can prevent incomplete excision and recurrence, spare additional surgery, and offer hormonal therapy options.

3.
Mol Cancer Res ; 21(10): 1079-1092, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37364049

RESUMO

Correlations between the oxidative stress response and metabolic reprogramming have been observed during malignant tumor formation; however, the detailed mechanism remains elusive. The transcription factor Nrf2, a master regulator of the oxidative stress response, mediates metabolic reprogramming in multiple cancers. In a mouse model of hepatocellular carcinoma (HCC), through metabolic profiling, genome-wide gene expression, and chromatin structure analyses, we present new evidence showing that in addition to altering antioxidative stress response signaling, Nrf2 ablation impairs multiple metabolic pathways to reduce the generation of acetyl-CoA and suppress histone acetylation in tumors, but not in tumor-adjacent normal tissue. Nrf2 ablation and dysregulated histone acetylation impair transcription complex assembly on downstream target antioxidant and metabolic regulatory genes for expression regulation. Mechanistic studies indicate that the regulatory function of Nrf2 is low glucose dependent, the effect of which is demolished under energy refeeding. Together, our results implicate an unexpected effect of Nrf2 on acetyl-CoA generation, in addition to its classic antioxidative stress response regulatory activity, integrates metabolic and epigenetic programs to drive HCC progression. IMPLICATIONS: This study highlights that Nrf2 integrates metabolic and epigenetic regulatory networks to dictate tumor progression and that Nrf2 targeting is therapeutically exploitable in HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Acetilcoenzima A/genética , Acetilcoenzima A/metabolismo , Carcinoma Hepatocelular/patologia , Epigênese Genética , Histonas/metabolismo , Neoplasias Hepáticas/patologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo
4.
Am J Cancer Res ; 13(1): 118-142, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36777508

RESUMO

Patients suffering from chronic pancreatitis (CP) have a higher risk of pancreatic ductal adenocarcinoma (PDAC) compared to the general population. For instance, the presence of an activated pancreatic stellate cell (PaSC)-rich stroma in CP has facilitated the progression of non-invasive pancreatic intraepithelial neoplasia (PanIN) lesions to invasive PDAC. We have previously found that in a mouse model of CP, NADPH oxidase 1 (Nox1) in activated PaSCs forms fibrotic tissue and up-regulates both matrix metalloproteinase (MMP) 9 and the transcription factor Twist1. Yet, the role and mechanism of Nox1 in activated PaSCs from mice with CP (CP-activated PaSCs) in the progression of PDAC is unknown. For that, we tested the ability of Nox1 in CP-activated PaSCs to facilitate the growth of pancreatic cancer cells, and the mechanisms involved in these effects by identifying proteins in the secretome of CP-activated PaSCs whose production were Nox1-dependent. We found that, in vitro, Nox1 evoked a pro-invasive and cancer-promoting phenotype in CP-activated PaSCs via Twist1/MMP-9 expression, causing changes in the extracellular matrix composition. In vivo, Nox1 in CP-activated PaSCs facilitated tumor growth and stromal expansion. Using mass spectrometry, we identified proteins protecting from endoplasmic reticulum, oxidative and metabolic stresses in the secretome of CP-activated PaSCs whose production was Nox1-dependent, including peroxiredoxins (Prdx1 and Prdx4), and thioredoxin reductase 1. In conclusion, inhibiting the Nox1 signaling in activated PaSCs from patients with CP at early stages can reduce the reorganization of extracellular matrix, and the protection of neoplastic cells from cellular stresses, ameliorating the progression of PDAC.

5.
Int J Oncol ; 62(2)2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36524361

RESUMO

The epidermal growth factor receptor (EGFR) is commonly upregulated in multiple cancer types, including breast cancer. In the present study, evidence is provided in support of the premise that upregulation of the EGFR/MEK1/MAPK1/2 signaling axis during antiestrogen treatment facilitates the escape of breast cancer cells from BimEL­dependent apoptosis, conferring resistance to therapy. This conclusion is based on the findings that ectopic BimEL cDNA overexpression and confocal imaging studies confirm the pro­apoptotic role of BimEL in ERα expressing breast cancer cells and that upregulated EGFR/MEK1/MAPK1/2 signaling blocks BimEL pro­apoptotic action in an antiestrogen­resistant breast cancer cell model. In addition, the present study identified a pro­survival role for autophagy in antiestrogen resistance while EGFR inhibitor studies demonstrated that a significant percentage of antiestrogen­resistant breast cancer cells survive EGFR targeting by pro­survival autophagy. These pre­clinical studies establish the possibility that targeting both the MEK1/MAPK1/2 signaling axis and pro­survival autophagy may be required to eradicate breast cancer cell survival and prevent the development of antiestrogen resistance following hormone treatments. The present study uniquely identified EGFR upregulation as one of the mechanisms breast cancer cells utilize to evade the cytotoxic effects of antiestrogens mediated through BimEL­dependent apoptosis.


Assuntos
Apoptose , Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Moduladores de Receptor Estrogênico , Feminino , Humanos , Apoptose/efeitos dos fármacos , Proteína 11 Semelhante a Bcl-2/efeitos dos fármacos , Proteína 11 Semelhante a Bcl-2/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/fisiologia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Moduladores de Receptor Estrogênico/farmacologia , Moduladores de Receptor Estrogênico/uso terapêutico , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Regulação para Cima , Transdução de Sinais
6.
J Neurosurg Case Lessons ; 4(16)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36254356

RESUMO

BACKGROUND: Neurocysticercosis is a parasitic infection that commonly affects the ventricles, subarachnoid spaces, and spinal cord of the central nervous system. The authors report an unusual manifestation of purely posterior fossa neurocysticercosis treated with endoscope-assisted open craniotomy for resection. OBSERVATIONS: A 67-year-old male presented with 2 months of progressive dizziness, gait ataxia, headaches, decreased hearing, and memory impairment. Imaging revealed an extra-axial cystic lesion occupying the foramen magnum and left cerebellopontine angle with significant mass effect and evidence of early hydrocephalus. Gross-total resection was accomplished via a left far lateral craniotomy with open endoscopic assistance, and pathological findings were consistent with neurocysticercosis. Postoperatively, he was noted to have a sixth nerve palsy, and adjuvant therapy included albendazole. By 9 months postoperatively, he exhibited complete resolution of an immediate postoperative sixth nerve palsy in addition to all preoperative symptoms. His hydrocephalus resolved and did not require permanent cerebrospinal fluid (CSF) diversion. LESSONS: When combined with traditional skull base approaches, open endoscopic techniques allow for enhanced visualization and resection of complex lesions otherwise inaccessible under the microscope alone. Recognition and obliteration of central nervous system neurocysticercosis can facilitate excellent neurological recovery without the need for CSF diversion.

7.
Cureus ; 14(6): e25756, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35812607

RESUMO

Human intestinal spirochetosis (HIS) is a condition where spirochetes, a group of spiral-shaped bacteria, attach to the apical membrane of the human colorectal epithelium. Although most findings of HIS are simply incidental discoveries found during screening colonoscopies, the ability to mimic the presentation of inflammatory bowel diseases should prompt consideration of this condition as part of a working differential diagnosis. Herein, we present the case of a 57-year-old bisexual, African American male with a medical history of Human Immunodeficiency Virus (HIV) on antiretroviral therapy (ART) with an undetectable viral load that presented for an elective, outpatient colonoscopy after experiencing four months of intermittent bloating and hematochezia. Histologic examination of colonic biopsies confirmed a diagnosis of HIS. The nonspecific clinical presentation in the setting of well-controlled HIV makes HIS a formidable diagnostic challenge that requires increased awareness.

8.
Cancer Med ; 11(6): 1573-1586, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35137551

RESUMO

Understanding the complex tumor microenvironment is key to the development of personalized therapies for the treatment of cancer including colorectal cancer (CRC). In the past decade, significant advances in the field of immunotherapy have changed the paradigm of cancer treatment. Despite significant improvements, tumor heterogeneity and lack of appropriate classification tools for CRC have prevented accurate risk stratification and identification of a wider patient population that may potentially benefit from targeted therapies. To identify novel signatures for accurate prognostication of CRC, we quantified gene expression of 12 immune-related genes using a medium-throughput NanoString quantification platform in 93 CRC patients. Multivariate prognostic analysis identified a combined four-gene prognostic signature (TGFB1, PTK2, RORC, and SOCS1) (HR: 1.76, 95% CI: 1.05-2.95, *p < 0.02). The survival trend was captured in an independent gene expression data set: GSE17536 (177 patients; HR: 3.31, 95% CI: 1.99-5.55, *p < 0.01) and GSE14333 (226 patients; HR: 2.47, 95% CI: 1.35-4.53, *p < 0.01). Further, gene set enrichment analysis of the TCGA data set associated higher prognostic scores with epithelial-mesenchymal transition (EMT) and inflammatory pathways. Comparatively, a lower prognostic score was correlated with oxidative phosphorylation and MYC and E2F targets. Analysis of immune parameters identified infiltration of T-reg cells, CD8+ T cells, M2 macrophages, and B cells in high-risk patient groups along with upregulation of immune exhaustion genes. This molecular study has identified a novel prognostic gene signature with clinical utility in CRC. Therefore, along with prognostic features, characterization of immune cell infiltrates and immunosuppression provides actionable information that should be considered while employing personalized medicine.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias Colorretais , Linfócitos T CD8-Positivos/patologia , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , Microambiente Tumoral/genética
9.
Am J Med Sci ; 361(3): 383-387, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33729918

RESUMO

Hypercalcemia and weight loss in a renal transplant patient especially with history of parathyroidectomy raises concern for an underlying malignancy, fungal infections or granulomatous disease. We present a case of 45-year-old male with history of subtotal parathyroidectomy presented with severe persistent hypercalcemia, acute kidney injury (AKI) and significant weight loss. An extensive workup revealed disseminated histoplasmosis. Hypercalcemia (which was refractory to initial medical management) and other symptoms resolved after a few weeks of initiating the antifungal treatment.


Assuntos
Injúria Renal Aguda/etiologia , Histoplasmose/diagnóstico , Hipercalcemia/etiologia , Transplante de Rim/efeitos adversos , Paratireoidectomia/efeitos adversos , Redução de Peso , Injúria Renal Aguda/diagnóstico , Diagnóstico Diferencial , Histoplasmose/complicações , Histoplasmose/diagnóstico por imagem , Humanos , Hipercalcemia/diagnóstico , Masculino , Pessoa de Meia-Idade
10.
Cureus ; 13(1): e12619, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33585108

RESUMO

Basaloid squamous cell carcinoma (BSCC) is a poorly differentiated variant of squamous cell carcinoma (SCC) with distinct morphologic characteristics. Yet, there are no clearly defined guidelines established for management. BSCC in the esophagus is a very rare entity, with the proportion of esophageal BSCC ranging from 0.068% to 11%. This wide range is thought to be secondary to difficulty making the diagnosis on small biopsy specimens and the lack of a universally defined proportion of BSCC components necessary to make the diagnosis. We present the case of a 57-year-old African American female, who underwent esophagogastroduodenoscopy (EGD) after an abnormal barium swallow in the setting of two months history of dysphagia and weight loss and was diagnosed with BSCC of the esophagus on histopathology.

11.
J Natl Med Assoc ; 113(3): 252-254, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33454137

RESUMO

Spontaneous gallbladder hemorrhage (SGBH) is a rare diagnosis related to trauma, malignancy or vascular abnormalities, associated with significant morbidity and mortality. We present a case of SGBH in a 55-year-old patient with right upper quadrant (RUQ) pain following initiation of apixaban for deep vein thrombosis post recent kidney transplant. Multiple imaging studies revealed a distended gallbladder with heterogeneous hyperdense material in the lumen and cystic duct obstruction. Surgery revealed a gallbladder with chronic cholecystitis, hemorrhage and hematoma. This case highlights a rare adverse event of anticoagulation, and SGBH should be considered when acute RUQ pain occurs in this setting.


Assuntos
Colecistite , Fator Xa , Hemorragia/induzido quimicamente , Humanos , Pessoa de Meia-Idade , Ultrassonografia
12.
Clin Cancer Res ; 25(14): 4363-4374, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30914433

RESUMO

PURPOSE: Breast cancers with BRCA1/2 alterations have a relatively high mutational load, suggesting that immune checkpoint blockade may be a potential treatment option. However, the degree of immune cell infiltration varies widely, and molecular features contributing to this variability remain unknown. EXPERIMENTAL DESIGN: We hypothesized that genomic signatures might predict immunogenicity in BRCA1/2 breast cancers. Using The Cancer Genome Atlas (TCGA) genomic data, we compared breast cancers with (89) and without (770) either germline or somatic BRCA1/2 alterations. We also studied 35 breast cancers with germline BRCA1/2 mutations from Penn using WES and IHC. RESULTS: We found that homologous recombination deficiency (HRD) scores were negatively associated with expression-based immune indices [cytolytic index (P = 0.04), immune ESTIMATE (P = 0.002), type II IFN signaling (P = 0.002)] despite being associated with a higher mutational/neoantigen burden, in BRCA1/2 mutant breast cancers. Further, absence of allele-specific loss of heterozygosity (LOH negative; P = 0.01) or subclonality (P = 0.003) of germline and somatic BRCA1/2 mutations, respectively, predicted for heightened cytolytic activity. Gene set analysis found that multiple innate and adaptive immune pathways that converge on NF-κB may contribute to this heightened immunogenicity. IHC of Penn breast cancers demonstrated increased CD45+ (P = 0.039) and CD8+ infiltrates (P = 0.037) and increased PDL1 expression (P = 0.012) in HRD-low or LOH-negative cancers. Triple-negative cancers with low HRD had far greater CD8+ T cells (P = 0.0011) and Perforin 1 expression (P = 0.014) compared with hormone receptor-positive HRD-high cancers. CONCLUSIONS: HRD scores and hormone receptor subtype are predictive of immunogenicity in BRCA1/2 breast cancers and may inform the design of optimal immune therapeutic strategies.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Linfócitos T CD8-Positivos/imunologia , Recombinação Homóloga , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Genômica/métodos , Humanos
13.
Nat Commun ; 8(1): 319, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28831036

RESUMO

Complete loss of BRCA1 or BRCA2 function is associated with sensitivity to DNA damaging agents. However, not all BRCA1 and BRCA2 germline mutation-associated tumors respond. Herein we report analyses of 160 BRCA1 and BRCA2 germline mutation-associated breast and ovarian tumors. Retention of the normal BRCA1 or BRCA2 allele (absence of locus-specific loss of heterozygosity (LOH)) is observed in 7% of BRCA1 ovarian, 16% of BRCA2 ovarian, 10% of BRCA1 breast, and 46% of BRCA2 breast tumors. These tumors have equivalent homologous recombination deficiency scores to sporadic tumors, significantly lower than scores in tumors with locus-specific LOH (ovarian, P = 0.0004; breast P < 0.0001, two-tailed Student's t-test). Absence of locus-specific LOH is associated with decreased overall survival in ovarian cancer patients treated with platinum chemotherapy (P = 0.01, log-rank test). Locus-specific LOH may be a clinically useful biomarker to predict primary resistance to DNA damaging agents in patients with germline BRCA1 and BRCA2 mutations.Most tumours associated with germline BRCA1/BRCA2 loss of function mutations respond to DNA damaging agents, however, some do not. Herein, the authors identify that a subset of breast/ovarian tumors retain a normal allele, which is associated with decreased overall survival after DNA damage-inducing platinum chemotherapy.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Mutação em Linhagem Germinativa , Perda de Heterozigosidade , Neoplasias Ovarianas/genética , Adulto , Idoso , Proteína BRCA1/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Metilação de DNA , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Regiões Promotoras Genéticas/genética , Modelos de Riscos Proporcionais
14.
PLoS One ; 8(9): e74230, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24069284

RESUMO

P. gingivalis (Pg), a causative agent of chronic generalized periodontitis, has been implicated in promoting cardiovascular disease. Expression of lipoprotein gene PG0717 of Pg strain W83 was found to be transiently upregulated during invasion of human coronary artery endothelial cells (HCAEC), suggesting this protein may be involved in virulence. We characterized the virulence phenotype of a PG0717 deletion mutant of pg W83. There were no differences in the ability of W83Δ717 to adhere and invade HCAEC. However, the increased proportion of internalized W83 at 24 hours post-inoculation was not observed with W83∆717. Deletion of PG0717 also impaired the ability of W83 to usurp the autophagic pathway in HCAEC and to induce autophagy in Saos-2 sarcoma cells. HCAEC infected with W83Δ717 also secreted significantly greater amounts of MCP-1, IL-8, IL-6, GM-CSF, and soluble ICAM-1, VCAM-1, and E-selectin when compared to W83. Further characterization of W83Δ717 revealed that neither capsule nor lipid A structure was affected by deletion of PG0717. Interestingly, the activity of both arginine (Rgp) and lysine (Kgp) gingipains was reduced in whole-cell extracts and culture supernatant of W83Δ717. RT-PCR revealed a corresponding decrease in transcription of rgpB but not rgpA or kgp. Quantitative proteome studies of the two strains revealed that both RgpA and RgpB, along with putative virulence factors peptidylarginine deiminase and Clp protease were significantly decreased in the W83Δ717. Our results suggest that PG0717 has pleiotropic effects on W83 that affect microbial induced manipulation of host responses important for microbial clearance and infection control.


Assuntos
Adesinas Bacterianas/metabolismo , Cisteína Endopeptidases/metabolismo , Deleção de Genes , Lipoproteínas/genética , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/metabolismo , Adesinas Bacterianas/genética , Autofagia , Aderência Bacteriana , Cápsulas Bacterianas/metabolismo , Células Cultivadas , Cisteína Endopeptidases/genética , Células Endoteliais/metabolismo , Células Endoteliais/microbiologia , Regulação Bacteriana da Expressão Gênica , Cisteína Endopeptidases Gingipaínas , Interações Hospedeiro-Patógeno , Humanos , Inflamação/metabolismo , Inflamação/microbiologia , Lipídeo A/metabolismo , Proteômica , Fatores de Virulência/genética
15.
J Biol Chem ; 284(43): 29945-55, 2009 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-19710018

RESUMO

The cyclin-dependent kinase (Cdk) family is emerging as an important therapeutic target in the treatment of cancer. Cdks 1, 2, 4, and 6 are the key members that regulate the cell cycle, as opposed to Cdks that control processes such as transcription (Cdk7 and Cdk9). For this reason, Cdks 1, 2, 4, and 6 have been the subject of extensive cell cycle-related research, and consequently many inhibitors have been developed to target these proteins. However, the compounds that comprise the current list of Cdk inhibitors are largely ATP-competitive. Here we report the identification of a novel structural site on Cdk2, which is well conserved between the cell cycle Cdks. Small molecules identified by a high throughput in silico screen of this pocket exhibit cytostatic effects and act by reducing the apparent protein levels of cell cycle Cdks. Drug-induced cell cycle arrest is associated with decreased Rb phosphorylation and decreased expression of E2F-dependent genes. Multiple lines of evidence indicate that the primary mechanism of action of these compounds is the direct induction of Cdk1, Cdk2, and Cdk4 protein aggregation.


Assuntos
Ciclo Celular/efeitos dos fármacos , Quinases Ciclina-Dependentes/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Trifosfato de Adenosina/metabolismo , Linhagem Celular , Quinases Ciclina-Dependentes/metabolismo , Fatores de Transcrição E2F/metabolismo , Indução Enzimática/efeitos dos fármacos , Humanos , Proteína do Retinoblastoma/metabolismo
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