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1.
J Gen Intern Med ; 38(7): 1705-1708, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36729085

RESUMO

BACKGROUND: Inadequate support for underrepresented-in-medicine physicians, lack of physician knowledge about structural drivers of health, and biased patient care and research widen US health disparities. Despite stating the importance of health equity and diversity, national physician education organizations have not yet prioritized these goals. AIM: To develop a comprehensive set of Health Justice Standards within our residency program to address structural drivers of inequity. SETTING: The J. Willis Hurst Internal Medicine Residency Program of Emory University is an academic internal medicine residency program located in Atlanta, Georgia. PARTICIPANTS: This initiative was led by the resident-founded Churchwell Diversity and Inclusion Collective, modified by Emory IM leadership, and presented to Emory IM residents. PROGRAM DESCRIPTION: We used an iterative process to develop and implement these Standards and shared our progress with our coresidents to evaluate impact. PROGRAM EVALUATION: In the year since their development, we have made demonstrable progress in each domain. Presentation of our work significantly correlated with increased resident interest in advocacy (p<0.001). DISCUSSION: A visionary, actionable health justice framework can be used to generate changes in residency programs' policies and should be developed on a national level.


Assuntos
Internato e Residência , Medicina , Humanos , Educação de Pós-Graduação em Medicina , Georgia , Liderança
3.
Curr Oncol ; 29(10): 6754-6763, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36290808

RESUMO

BACKGROUND: Most patients with pancreatic ductal adenocarcinoma (PDAC) are metastatic at presentation with dismal prognosis warranting improved systemic therapy options. Longitudinal sampling for the assessment of treatment response poses a challenge for validating novel therapies. In this case study, we evaluate the feasibility of collecting endoscopic ultrasound (EUS)-guided longitudinal fine-needle aspiration biopsies (FNABs) from two PDAC patients and conduct gene expression studies associated with tumour microenvironment changes associated with radiofrequency ablation (RFA). METHODS: EUS-guided serial/longitudinal FNABs of tumour were collected before and after treatment from two stage III inoperable gemcitabine-treated PDAC patients treated with targeted RFA three times. Biopsies were analysed using a custom NanoString panel (144 genes) consisting of cancer and cancer-associated fibroblast (CAFs) subtypes and immune changes. CAF culture was established from one FNAB and characterised by immunofluorescence and immunoblotting. RESULTS: Two-course RFA led to the upregulation of the CD1E gene (involved in antigen presentation) in both patients 1 and 2 (4.5 and 3.9-fold changes) compared to baseline. Patient 1 showed increased T cell genes (CD4-8.7-fold change, CD8-35.7-fold change), cytolytic function (6.4-fold change) and inflammatory response (8-fold change). A greater than 2-fold upregulation of immune checkpoint genes was observed post-second RFA in both patients. Further, two-course RFA led to increased PDGFRα (4.5-fold change) and CAF subtypes B and C genes in patient 1 and subtypes A, B and D genes in patient 2. Patient 2-derived CAFs post-first RFA showed expression of PDGFRα, POSTN and MYH11 proteins. Finally, RFA led to the downregulation of classical PDAC subtype-specific genes in both patients. CONCLUSIONS: This case study suggests longitudinal EUS-FNAB as a potential resource to study tumour and microenvironmental changes associated with RFA treatment. A large sample size is required in the future to assess the efficacy and safety of the treatment and perform comprehensive statistical analysis of EUS-RFA-based molecular changes in PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Ablação por Radiofrequência , Humanos , Microambiente Tumoral , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/cirurgia , Biópsia , Ultrassonografia de Intervenção , Expressão Gênica , Neoplasias Pancreáticas
4.
Transl Oncol ; 25: 101511, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35964339

RESUMO

PURPOSE: Triple-negative breast cancer (TNBC) is a heterogeneous disease with a significant challenge to effectively manage in the clinic worldwide. Immunotherapy may be beneficial to TNBC patients if responders can be effectively identified. Here we sought to elucidate the immune landscape of TNBCs by stratifying patients into immune-specific subtypes (immunotypes) to decipher the molecular and cellular presentations and signaling events of this heterogeneous disease and associating them with their clinical outcomes and potential treatment options. EXPERIMENTAL DESIGN: We profiled 730 immune genes in 88 retrospective Indian TNBC samples using the NanoString platform, established immunotypes using non-negative matrix factorization-based machine learning approach, and validated them using Western TNBCs (n=422; public datasets). Immunotype-specific gene signatures were associated with clinicopathological features, immune cell types, biological pathways, acute/chronic inflammatory responses, and immunogenic cell death processes. Responses to different immunotherapies associated with TNBC immunotypes were assessed using cross-cancer comparison to melanoma (n=504). Tumor-infiltrating lymphocytes (TILs) and pan-macrophage spatial marker expression were evaluated. RESULTS: We identified three robust transcriptome-based immunotypes in both Indian and Western TNBCs in similar proportions. Immunotype-1 tumors, mainly representing well-known claudin-low and immunomodulatory subgroups, harbored dense TIL infiltrates and T-helper-1 (Th1) response profiles associated with smaller tumors, pre-menopausal status, and a better prognosis. They displayed a cascade of events, including acute inflammation, damage-associated molecular patterns, T-cell receptor-related and chemokine-specific signaling, antigen presentation, and viral-mimicry pathways. On the other hand, immunotype-2 was enriched for Th2/Th17 responses, CD4+ regulatory cells, basal-like/mesenchymal immunotypes, and an intermediate prognosis. In contrast to the two T-cell enriched immunotypes, immunotype-3 patients expressed innate immune genes/proteins, including those representing myeloid infiltrations (validated by spatial immunohistochemistry), and had poor survival. Remarkably, a cross-cancer comparison analysis revealed the association of immunotype-1 with responses to anti-PD-L1 and MAGEA3 immunotherapies. CONCLUSION: Overall, the TNBC immunotypes identified in TNBCs reveal different prognoses, immune infiltrations, signaling, acute/chronic inflammation leading to immunogenic cell death of cancer cells, and potentially distinct responses to immunotherapies. The overlap in immune characteristics in Indian and Western TNBCs suggests similar efficiency of immunotherapy in both populations if strategies to select patients according to immunotypes can be further optimized and implemented.

5.
Lupus ; 31(4): 472-481, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35258358

RESUMO

BACKGROUND: Antimalarials are first-line systemic therapy for cutaneous lupus erythematosus (CLE). While some patients unresponsive to hydroxychloroquine (HCQ) alone benefit from the addition of quinacrine (QC), a subset of patients is refractory to both antimalarials. METHODS: We classified CLE patients as HCQ-responders, HCQ+QC-responders, or HCQ+QC-nonresponders to compare immune profiles. Immunohistochemistry, immunofluorescence, and qRT-PCR were used to characterize inflammatory cells and cytokines in lesional skin. RESULTS: Immunohistochemistry showed that CD69+ T cells were higher in HCQ+QC-nonresponders compared to HCQ- and HCQ+QC-responders (p < 0.05). Immunofluorescence further identified these cells as CD69+CCR7+ circulating activated T cells. Myeloid dendritic cells were significantly higher in HCQ+QC-responders compared to both HCQ-responders and HCQ+QC-nonresponders. Plasmacytoid dendritic cells were significantly increased in HCQ-responders compared to HCQ- and HCQ+QC-nonresponders. No differences were found in the number of autoreactive T cells, MAC387+ cells, and neutrophils among the groups. CLASI scores of the HCQ+QC-nonresponder group positively correlated with CD69+CCR7+ circulating activated T cells (r = 0.6335, p < 0.05) and MAC387+ cells (r = 0.5726, p < 0.05). IL-17 protein expression was higher in HCQ+QC-responders compared to HCQ-responders or HCQ+QC-nonresponders, while IL-22 protein expression did not differ. mRNA expression demonstrated increased STAT3 expression in a subset of HCQ+QC-nonresponders. CONCLUSION: An increased number of CD69+CCR7+ circulating activated T cells and a strong correlation with CLASI scores in the HCQ+QC-nonresponders suggest these cells are involved in antimalarial-refractory skin disease. STAT3 is also increased in HCQ+QC-nonresponders and may also be a potential target for antimalarial-refractory skin disease.


Assuntos
Lúpus Eritematoso Cutâneo/tratamento farmacológico , Receptores CCR7 , Fator de Transcrição STAT3 , Antígenos CD , Antígenos de Diferenciação de Linfócitos T , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Feminino , Imunofluorescência , Humanos , Hidroxicloroquina/uso terapêutico , Imuno-Histoquímica , Lectinas Tipo C , Lúpus Eritematoso Cutâneo/imunologia , Masculino , Pessoa de Meia-Idade , Quinacrina/uso terapêutico , Receptores CCR7/uso terapêutico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Linfócitos T , Resultado do Tratamento
6.
Lung India ; 38(6): 577-580, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34747743

RESUMO

Paraneoplastic and autoimmune encephalitis (AIE) syndromes describe a range of inflammatory disorders of the brain. "Classic" paraneoplastic encephalitis syndromes occur due to a remote neoplasm and are associated with antibodies that target intracellular neuronal proteins while the more recently described AIE syndromes are not always paraneoplastic and occur in association with antibodies that target cell-surface neuronal receptors (e.g., anti-NMDA receptor, anti-LGI1, anti-GABAB receptor).[1] Diagnosis can be difficult and delayed due to nonspecific clinical, imaging, and laboratory findings, and in those syndromes associated with a neoplasm, the neurologic syndromes often precede the cancer diagnosis. We present a case of a 64-year-old patient diagnosed with anti-GABAB receptor encephalitis that subsequently revealed an underlying small cell lung cancer without a primary lung tumor. This case highlights the clinical challenge in diagnosing immune-mediated encephalitis, its methodical work up, and subsequent management.

7.
J Am Coll Emerg Physicians Open ; 2(5): e12531, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34568869

RESUMO

Immune thrombocytopenic purpura (ITP) is a rare complication associated with vaccines targeting various diseases, including influenza, measles-mumps-rubella, hepatitis B, and diphtheria-tetanus-pertussis. We report 2 cases of ITP in healthy 20-year-old and 21-year-old women presenting to Emory University in Atlanta, GA, 2 days after the second dose and 11 days after the first dose (respectively) of the Pfizer-BioNTech messenger RNA severe acute respiratory syndrome coronavirus 2 vaccine. Both patients recovered quickly. With more than a billion doses of coronavirus disease 2019 vaccines safely administered worldwide as of May 2021, discussions with patients should put into perspective the low risks of vaccination against the enormous societal benefit of the coronavirus disease 2019 vaccine.

9.
Clin Cancer Res ; 25(11): 3392-3403, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30770349

RESUMO

PURPOSE: ATR inhibitors (ATRi) are in early phase clinical trials and have been shown to sensitize to chemotherapy and radiotherapy preclinically. Limited data have been published about the effect of these drugs on the tumor microenvironment.Experimental Design: We used an immunocompetent mouse model of HPV-driven malignancies to investigate the ATR inhibitor AZD6738 in combination with fractionated radiation (RT). Gene expression analysis and flow cytometry were performed posttherapy. RESULTS: Significant radiosensitization to RT by ATRi was observed alongside a marked increase in immune cell infiltration. We identified increased numbers of CD3+ and NK cells, but most of this infiltrate was composed of myeloid cells. ATRi plus radiation produced a gene expression signature matching a type I/II IFN response, with upregulation of genes playing a role in nucleic acid sensing. Increased MHC I levels were observed on tumor cells, with transcript-level data indicating increased antigen processing and presentation within the tumor. Significant modulation of cytokine gene expression (particularly CCL2, CCL5, and CXCL10) was found in vivo, with in vitro data indicating CCL3, CCL5, and CXCL10 are produced from tumor cells after ATRi + RT. CONCLUSIONS: We show that DNA damage by ATRi and RT leads to an IFN response through activation of nucleic acid-sensing pathways. This triggers increased antigen presentation and innate immune cell infiltration. Further understanding of the effect of this combination on the immune response may allow modulation of these effects to maximize tumor control through antitumor immunity.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Neoplasias/etiologia , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Animais , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Camundongos , Células Mieloides/efeitos dos fármacos , Células Mieloides/imunologia , Células Mieloides/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Radiação Ionizante , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Transl Oncol ; 10(4): 699-706, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28704710

RESUMO

Hormone receptor positive (HR+) breast cancers are a heterogeneous class with differential prognosis. Although more than half of Indian women present with advanced disease, many such patients do well. We have attempted identification of biologically indolent tumors within HR+HER2- tumors based on gene expression using histological grade as a guide to tumor aggression. 144 HR+HER2- tumors were divided into subclasses based on scores derived by using transcript levels of multiple genes representing survival, proliferation, and apoptotic pathways and compared to classification by Ki-67 labeling index (LI). Clinical characters and disease free survival were compared between the subclasses. The findings were independently validated in the METABRIC data set. Using the previously established estrogen receptor (ER) down stream activity equation, 20% of the tumors with greater than 10% HR positivity by immunohistochemistry (IHC) were still found to have inadequate ER function. A tumor aggression probability score was used to segregate the remainder of tumors into indolent (22%) and aggressive (58%) classes. Significant difference in disease specific survival was seen between the groups (P = .02). Aggression probability based subclassification had a higher hazard ratio and also independent prognostic value (P<.05). Independent validation of the gene panel in the METABRIC data set showed all 3 classes; indolent (24%), aggressive (68%), and insufficient ER signaling (7%) with differential survival (P = .01). In agreement with other recent reports, biologically indolent tumors can be identified with small sets of gene panels and these tumors exist in a population with predominantly late stage disease.

11.
Tumour Biol ; 39(3): 1010428317695028, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28349782

RESUMO

Despite an overall good prognosis, a significant proportion of patients with hormone receptor positive human epidermal growth factor receptor 2 negative breast cancers develop distant metastases. The metastatic potential of epithelial cells is known to be regulated by tumor-stromal interaction and mediated by epithelial-to-mesenchymal transition. Hormone receptor positive human epidermal growth factor receptor 2 negative tumors were used to estimate markers of epithelial-to-mesenchymal transition, and the luminal breast cancer cell line MCF-7 was used to examine the interactions between integrins and growth factor receptors in causation of epithelial-to-mesenchymal transition. A total of 140 primary tumors were sub-divided into groups enriched for the markers of epithelial-to-mesenchymal transition (snail family transcriptional repressor 2 and integrin ß6) versus those with low levels. Within the epithelial-to-mesenchymal transition+ tumors, there was a positive correlation between the transcripts of integrin ß6 and growth factor receptors-human epidermal growth factor receptor 2 and epidermal growth factor receptor. In tumors enriched for epithelial-to-mesenchymal transition markers, patients with tumors with the highest quartile of growth factor receptor transcripts had a shorter disease-free survival compared to patients with low growth factor receptor expression by Kaplan-Meier analysis (log rank, p = 0.03). Epithelial-to-mesenchymal transition was induced in MCF-7 cells by treatment with transforming growth factor beta 1 and confirmed by upregulation of SNAI1 and SNAI2 transcripts, increase of vimentin and integrin ß6 protein, and repression of E-cadherin. Treatment of these cells with the dual-specificity tyrosine-kinase inhibitor lapatinib led to downregulation of epithelial-to-mesenchymal transition as indicated by lower levels of SNAI1 and SNAI2 transcripts, integrin αvß6, and matrix metalloproteinase 9 protein. The results suggest that synergistic interactions between growth factor receptors and integrin ß6 could mediate epithelial-to-mesenchymal transition and migration in a subset of luminal breast cancers and lapatinib might be effective in disrupting this interaction.


Assuntos
Antígenos de Neoplasias/biossíntese , Neoplasias da Mama/tratamento farmacológico , Integrinas/biossíntese , Metaloproteinase 9 da Matriz/genética , Receptor ErbB-2/genética , Fatores de Transcrição da Família Snail/biossíntese , Idoso , Antígenos de Neoplasias/genética , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Caderinas/biossíntese , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Integrinas/genética , Estimativa de Kaplan-Meier , Lapatinib , Células MCF-7 , Metaloproteinase 9 da Matriz/biossíntese , Pessoa de Meia-Idade , Quinazolinas/administração & dosagem , Fatores de Transcrição da Família Snail/genética , Fator de Crescimento Transformador beta1/administração & dosagem , Fator de Crescimento Transformador beta1/genética
12.
Ann Emerg Med ; 69(5): 610-619.e1, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27856020

RESUMO

STUDY OBJECTIVE: Lumbar puncture is a commonly performed procedure, although previous studies have documented low rates of successful completion in infants. Ultrasonography can visualize the anatomic landmarks for lumbar puncture and has been shown in some studies to reduce the failure rate of lumbar puncture in adults. We seek to determine whether ultrasonography-assisted site marking increases success for infant lumbar punctures. METHODS: This was a prospective, randomized, controlled trial in an academic pediatric emergency department (ED). We enrolled a convenience sample of infants younger than 6 months between June 2014 and February 2016 and randomized them to either a traditional lumbar puncture arm or an ultrasonography-assisted lumbar puncture arm. Infants in the ultrasonography arm received bedside ultrasonography of the spine by one of 3 study sonographers before lumbar puncture, during which the conus medullaris and most appropriate intervertebral space were identified and marked. The lumbar puncture was then performed by the predetermined ED provider. Our primary outcome was successful first-attempt lumbar puncture. Subjects were considered to have a successful lumbar puncture if cerebrospinal fluid was obtained and RBC counts were less than 1,000/mm3. All outcomes were assessed by intention-to-treat analysis. RESULTS: One hundred twenty-eight patients were enrolled, with 64 in each arm. No differences between the 2 arms were found in the baseline characteristics of the study subjects and providers, except for sex and first-attempt position. The first-attempt success rate was higher for the ultrasonography arm (58%) versus the traditional arm (31%) (absolute risk difference 27% [95% CI 10% to 43%]). Success within 3 attempts was also higher for the ultrasonography arm (75%) versus the traditional arm (44%) (absolute risk difference 31% [95% CI 15% to 47%]). On average, performing bedside ultrasonography on 4 patients (95% CI 2.1 to 6.6) resulted in 1 additional successful lumbar puncture. CONCLUSION: Ultrasonography-assisted site marking improved infant lumbar puncture success in a tertiary care pediatric teaching hospital. This method has the potential to reduce unnecessary hospitalizations and exposures to antibiotics in this vulnerable population.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Punção Espinal/métodos , Ultrassonografia de Intervenção , Pontos de Referência Anatômicos/diagnóstico por imagem , Serviço Hospitalar de Emergência , Feminino , Humanos , Lactente , Masculino , Ultrassonografia de Intervenção/métodos
13.
Data Brief ; 8: 944-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27508248

RESUMO

Human breast cancers are a highly heterogeneous group of tumours consisting of several molecular subtypes with a variable profile of hormone, growth factor receptors and cytokeratins [1]. Here, the data shows immunofluorescence profiling of four different cell lines belonging to distinct clinical subtypes of breast cancer. Post revival, the cell lines were passaged in culture and immunophenotyping was done for ER, HER-2, AR and EGFR. Data for the markers from early passage (5th) through passages as late as 25 for the different cell lines is presented.

14.
Cancer Med ; 5(8): 2000-11, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27184932

RESUMO

Integrin αvß6 is involved in the transition from ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC) of the breast. In addition, integrin ß6 (ITGB6) is of prognostic value in invasive breast cancers, particularly in HER2+ subtype. However, pathways mediating the activity of integrin αvß6 in clinical progression of invasive breast cancers need further elucidation. We have examined human breast cancer specimens (N = 460) for the expression of integrin ß6 (ITGB6) mRNA by qPCR. In addition, we have examined a subset (N = 147) for the expression of αvß6 integrin by immunohistochemistry (IHC). The expression levels of members of Rho-Rac pathway including downstream genes (ACTR2, ACTR3) and effector proteinases (MMP9, MMP15) were estimated by qPCR in the HER2+ subset (N = 59). There is a significant increase in the mean expression of ITGB6 in HER2+ tumors compared to HR+HER2- and triple negative (TNBC) subtypes (P = 0.00). HER2+ tumors with the highest levels (top quartile) of ITGB6 have significantly elevated levels of all the genes of the Rho-Rac pathway (P-values from 0.01 to 0.0001). Patients in this group have a significantly shorter disease-free survival compared to the group with lower ITGB6 levels (HR = 2.9 (0.9-8.9), P = 0.05). The mean level of ITGB6 expression is increased further in lymph node-positive tumors. The increased regional and distant metastasis observed in HER2+ tumors with high levels of ITGB6 might be mediated by the canonical Rho-Rac pathway through increased expression of MMP9 and MMP15.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Cadeias beta de Integrinas/genética , Receptor ErbB-2/metabolismo , Transdução de Sinais , Proteínas rac de Ligação ao GTP/metabolismo , Adulto , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Feminino , Amplificação de Genes , Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Receptor ErbB-2/genética
15.
Exp Cell Res ; 346(1): 137-45, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27235542

RESUMO

Resistance to anthracycline based chemotherapy is a major limitation in the treatment of breast cancer, particularly of the triple negative sub-type that lacks targeted therapies. Resistance that arises from tumor-stromal interaction facilitated by integrins provides the possibility of targeted disruption. In the present study, we demonstrate that integrin ß3 signaling inhibits apoptosis induced by a DNA-damaging chemotherapeutic agent, epirubicin, in MDA-MB-231 breast cancer cells. Drug efflux based mechanisms do not contribute to this effect. We show that integrin ß3 employs the PI3K-Akt and the MAPK pathway for enabling cell survival and proliferation. Further, our results indicate that integrin ß3 helps inhibit epirubicin induced cytotoxicity by repression of the pro-apoptotic protein BAD, thus promoting an anti-apoptotic response. Myristoylated RGT peptide and a monoclonal antibody against integrin ß3 brought about a reversal of this effect and chemosensitized the cells. These results identify ß3 integrin signaling via repression of BAD as an important survival pathway used by breast cancer cells to evade chemotherapy induced stress.


Assuntos
Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Epirubicina/farmacologia , Integrina beta3/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo , Anticorpos Bloqueadores/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colágeno/metabolismo , Citometria de Fluxo , Humanos , Concentração Inibidora 50 , Ligantes , Ácido Mirístico/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
J Cancer ; 5(2): 156-65, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24563670

RESUMO

BACKGROUND: The 2010 guidelines by ASCO-CAP have mandated that breast cancer specimens with ≥1% positively staining cells by immunohistochemistry should be considered Estrogen Receptor (ER) positive. This has led to a subclass of low-ER positive (1-10%) breast cancers. We have examined the biology and clinical behavior of these low ER staining tumors. METHODS: We have developed a probabilistic score of the "ER-positivity" by quantitative estimation of ER related gene transcripts from FFPE specimens. Immunohistochemistry for ER was done on 240 surgically excised tumors of primary breast cancer. Relative transcript abundance of 3 house-keeping genes and 6 ER related genes were determined by q-RT PCR. A logistic regression model using 3 ER associated genes provided the best probability function, and a cut-off value was derived by ROC analysis. 144 high ER (>10%), 75 ER negative and 21 low-ER (1-10%) tumors were evaluated using the probability score and the disease specific survival was compared. RESULTS: Half of the low-ER positive tumors were assigned to the ER negative group based on the probability score; in contrast 95% of ER negative and 92% of the high ER positive tumors were assigned to the appropriate ER group (p<0.0001). The survival of the low-ER group was intermediate between that of the high ER positive and ER negative groups (p<0.05). CONCLUSION: Our results suggest that the newly lowered ASCO-CAP criteria for ER positivity, leads to the false categorization of biologically ER negative tumors as ER positive ones. This may have particular relevance to India, where we have a much higher proportion of ER negative tumors in general.

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