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1.
Oncologist ; 29(1): 47-56, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37390616

RESUMEN

BACKGROUND: Combination chemotherapy and immunotherapy regimens have significantly improved survival for patients with previously untreated advanced non-small cell lung cancer (NSCLC). Improvements in overall survival (OS) in two separate pembrolizumab trials have demonstrated survival improvements over chemotherapy alone, regardless of PD-L1 status. The optimal chemotherapy backbone for combination with immunotherapy is unknown. We hypothesized nab-paclitaxel may be a well-suited platinum partner to use in combination with checkpoint inhibitor therapy for both adenocarcinoma and squamous histology and conducted a phase I/II trial to assess the efficacy of this regimen in advanced NSCLC. METHODS: Adult patients with previously untreated, stage IIIB/IV NSCLC (any histology) with an Eastern Cooperative Oncology Group performance status of 0-1, any PD-L1 expression, and no EGFR mutations or ALK translocations, received carboplatin area under the curve (AUC) 6 day 1, nab-paclitaxel 100 mg/m2 days 1, 8, 15, and pembrolizumab 200 mg day 1 q21 days for 4 cycles followed by maintenance pembrolizumab q3w. Co-primary endpoints were progression-free survival (PFS) and overall response rate (ORR). RESULTS: Forty-six evaluable patients enrolled, 14 in phase I and 32 in phase II, from June 2015 to July 2018 with a median duration of follow-up of 35.4 months. Median time from enrollment to data lock was 42 months. In the ITT population, the ORR was 35%, median PFS was 5.6 months (95% CI, 4.6-8.2), and median OS was 15.4 months (CI, 12.4-28.1). There were no statistical differences in PFS or OS by PD-L1 status. The 2- and 3-year landmark OS rates were 33% and 24%, respectively. CONCLUSION: Carboplatin, nab-paclitaxel, and pembrolizumab are a safe and effective regimen for patients with both squamous and nonsquamous NSCLC. Although this study did not meet the prespecified endpoints, the median and landmark OS results are consistent with durable benefit of this regimen as seen in phase III trials for first-line treatment of advanced NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Adulto , Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Carboplatino/farmacología , Carboplatino/uso terapéutico , Antígeno B7-H1 , Neoplasias Pulmonares/patología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Paclitaxel , Carcinoma de Células Escamosas/tratamiento farmacológico
3.
Biomolecules ; 12(11)2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36358918

RESUMEN

In the past decade, defective DNA repair has been increasingly linked with cancer progression. Human tumors with markers of defective DNA repair and increased replication stress exhibit genomic instability and poor survival rates across tumor types. Seminal studies have demonstrated that genomic instability develops following inactivation of BRCA1, BRCA2, or BRCA-related genes. However, it is recognized that many tumors exhibit genomic instability but lack BRCA inactivation. We sought to identify a pan-cancer mechanism that underpins genomic instability and cancer progression in BRCA-wildtype tumors. Methods: Using multi-omics data from two independent consortia, we analyzed data from dozens of tumor types to identify patient cohorts characterized by poor outcomes, genomic instability, and wildtype BRCA genes. We developed several novel metrics to identify the genetic underpinnings of genomic instability in tumors with wildtype BRCA. Associated clinical data was mined to analyze patient responses to standard of care therapies and potential differences in metastatic dissemination. Results: Systematic analysis of the DNA repair landscape revealed that defective single-strand break repair, translesion synthesis, and non-homologous end-joining effectors drive genomic instability in tumors with wildtype BRCA and BRCA-related genes. Importantly, we find that loss of these effectors promotes replication stress, therapy resistance, and increased primary carcinoma to brain metastasis. Conclusions: Our results have defined a new pan-cancer class of tumors characterized by replicative instability (RIN). RIN is defined by the accumulation of intra-chromosomal, gene-level gain and loss events at replication stress sensitive (RSS) genome sites. We find that RIN accelerates cancer progression by driving copy number alterations and transcriptional program rewiring that promote tumor evolution. Clinically, we find that RIN drives therapy resistance and distant metastases across multiple tumor types.


Asunto(s)
Inestabilidad Genómica , Neoplasias , Humanos , Reparación del ADN/genética , Reparación del ADN por Unión de Extremidades , Neoplasias/genética , Replicación del ADN , Aberraciones Cromosómicas
4.
Front Oncol ; 12: 986236, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36212442

RESUMEN

Background: Frailty, sarcopenia and malnutrition are powerful predictors of clinical outcomes that are not routinely measured in patients with non-small cell lung cancer (NSCLC). The primary aim of this study was to investigate the association of sarcopenia, determined by the psoas muscle index (PMI) with overall survival (OS) in patients with advanced NSCLC treated with concurrent immune checkpoint inhibitor (ICI) and chemotherapy (CTX). Methods: We retrospectively reviewed data from a cohort of patients with locally advanced or metastatic NSCLC who were treated between 2015 and 2021 at the University of Virginia Medical Center. The cross-sectional area of the psoas muscle was assessed on CT or PET/CT imaging prior to treatment initiation. Multivariate analysis was performed using Cox proportional hazards regression models. Results: A total of 92 patients (median age: 64 years, range 36-89 years), 48 (52.2%) men and 44 (47.8%) women, were included in the study. The median follow-up was 29.6 months. The median OS was 17.8 months. Sarcopenia, defined by a PMI below the 25th percentile, was associated with significantly lower OS (9.1 months in sarcopenic patients vs. 22.3 months in non-sarcopenic patients, P = 0.002). Multivariate analysis revealed that sarcopenia (HR 2.12, P = 0.0209), ECOG ≥ 2 (HR 2.88, P = 0.0027), prognostic nutritional index (HR 3.02, P = 0.0034) and the absence of immune related adverse events (HR 2.04, P = 0.0185) were independently associated with inferior OS. Conclusions: Sarcopenia is independently associated with poor OS in patients with advanced NSCLC undergoing concurrent ICI and CTX.

5.
Clin Case Rep ; 9(6): e04227, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34188921

RESUMEN

Immunotherapy is an expanding area of cancer treatment with significant promise. Despite their efficacy, checkpoint inhibitors are associated with a number of immune-related adverse events; here, we described thrombocytopenia secondary todurvalumab.

6.
Oncologist ; 26(3): 224-230, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33098189

RESUMEN

BACKGROUND: Thousands of patients annually receive treatment for advanced non-small cell lung cancer (NSCLC), but little is known about their views on the decision to receive that treatment, or regret. This trial prospectively evaluated the incidence of regret and whether baseline characteristics, patient decision-making parameters, or clinical progress early in the treatment course predicts regret. MATERIALS AND METHODS: Patients receiving systemic treatment for advanced NSCLC completed every 3-week patient reported outcome (PRO) assessment using the electronic Lung Cancer Symptom Scale (eLCSS-QL), including the 3-Item Global Index (3-IGI; assessing overall distress, activities, and quality of life [QL]). A prespecified secondary aim was to determine the frequency of regret evaluated at 3 months after starting treatment. Patients were randomized to usual care or enhanced care (which included use of the DecisionKEYS decision aid). RESULTS: Of 164 patients entered, 160 received treatment and 142 were evaluable for regret. In total, 11.5% of patients and 9% of their supporters expressed regret. Baseline characteristics did not predict regret; regret was rarely expressed by those who had a less than 20% decline or improvement in the 3-IGI PRO score after two treatment cycles. In contrast, when asked if they would make the same decision again, only 1% not having a 20% 3-IGI decline expressed regret, versus 14% with a 3-IGI decline (p = .01). CONCLUSION: The majority of patients having regret were identified early using the PRO 3-IGI of the eLCSS-QL measure. Identifying patients at risk for regret allows for interventions, including frank discussions of progress and goals early in the treatment course, which could address regret in patients and their supporters. IMPLICATIONS FOR PRACTICE: This report documents prospectively, for the first time, the incidence of treatment-related regret in patients with advanced lung cancer and outlines that risk of regret is associated with patient-determined worsening health status early in the course of treatment. Identifying patients at risk for regret early in treatment (before the third cycle of treatment) appears to be crucial. Counseling at that time should include a discussion of consideration of treatment change and the reason for this change.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Toma de Decisiones , Emociones , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Estudios Prospectivos , Calidad de Vida
7.
J Neurooncol ; 149(2): 357-366, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32902767

RESUMEN

PURPOSE/OBJECTIVE(S): Tyrosine kinase inhibitors (TKIs) are commonly employed for patients with brain metastases from lung cancer and specific driver mutations. We sought to identify the correlation between intracranial tumor burden and outcomes in patients with brain metastases treated with TKIs. MATERIALS/METHODS: We identified and retrospectively reviewed cases of EGFR-mutant or ALK-rearranged lung cancer with brain metastases at any time during their cancer course. Clinical characteristics and treatment information were abstracted from the medical records. Brain metastases were contoured to calculate total volume of disease at diagnosis and after initial therapy. High intracranial burden was defined as either > 10 brain metastases, volume of brain metastases > 15 cc, or largest lesion > 3 cm. Intracranial response was determined according to Response Assessment in Neuro-Oncology (RANO) criteria on the patient level. We determined the correlation between clinical and imaging characteristics and intracranial progression free survival (IC-PFS) and overall survival (OS). RESULTS: Fifty-seven patients with EGFR (n = 49) and ALK (n = 8) alterations were identified. Median follow-up from initial brain metastasis diagnosis was 17 months. Neurological symptoms were present in 54% at brain metastasis diagnosis. For those receiving TKIs alone or TKIs with radiation, at least a partial intracranial response (≥ 65% volume reduction) at 3 months from starting therapy was achieved in 94% and 58%. Progressive intracranial disease at 3 months occurred in 6.3% and 8.3%. Patients with high intracranial burden (n = 21) had a median 17 brain metastases, 6.5 cc volume, and 1.9 cm maximal tumor diameter. Median IC-PFS and OS for patients with high intracranial burden was 13.9 and 35.4 months. Patients with high intracranial burden and neurological symptoms at diagnosis had similar IC-PFS and OS compared to those with low burden and absence of neurological symptoms (p > 0.05 for each). CONCLUSION: Most patients receiving TKIs as part of their initial therapy achieve an early and durable volumetric intracranial response, irrespective of presenting disease burden or neurologic symptoms.


Asunto(s)
Quinasa de Linfoma Anaplásico/genética , Neoplasias Encefálicas/terapia , Carcinoma de Pulmón de Células no Pequeñas/terapia , Reordenamiento Génico , Mutación , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Terapia Combinada , Irradiación Craneana/mortalidad , Receptores ErbB/genética , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Pronóstico , Inhibidores de Proteínas Quinasas/uso terapéutico , Estudios Retrospectivos , Tasa de Supervivencia
8.
Front Oncol ; 10: 585551, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33489883

RESUMEN

It has long been recognized that defects in cell cycle checkpoint and DNA repair pathways give rise to genomic instability, tumor heterogeneity, and metastasis. Despite this knowledge, the transcription factor-mediated gene expression programs that enable survival and proliferation in the face of enormous replication stress and DNA damage have remained elusive. Using robust omics data from two independent studies, we provide evidence that a large cohort of lung adenocarcinomas exhibit significant genome instability and overexpress the DNA damage responsive transcription factor MYB proto-oncogene like 2 (MYBL2). Across two studies, elevated MYBL2 expression was a robust marker of poor overall survival and disease-free survival outcomes, regardless of disease stage. Clinically, elevated MYBL2 expression identified patients with aggressive early onset disease, increased lymph node involvement, and increased incidence of distant metastases. Analysis of genomic sequencing data demonstrated that MYBL2 High lung adenocarcinomas had elevated somatic mutation burden, widespread chromosomal alterations, and alterations in single-strand DNA break repair pathways. In this study, we provide evidence that impaired single-strand break repair, combined with a loss of cell cycle regulators TP53 and RB1, give rise to MYBL2-mediated transcriptional programs. Omics data supports a model wherein tumors with significant genomic instability upregulate MYBL2 to drive genes that control replication stress responses, promote error-prone DNA repair, and antagonize faithful homologous recombination repair. Our study supports the use of checkpoint kinase 1 (CHK1) pharmacological inhibitors, in targeted MYBL2 High patient cohorts, as a future therapy to improve lung adenocarcinoma patient outcomes.

12.
Chin J Cancer Res ; 30(1): 72-83, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29545721

RESUMEN

OBJECTIVE: The complexity, heterogeneity and capacity of malignant neoplastic cells and tumors for rapid change and evolution suggest that living-cell-based biological-systems approaches to cancer treatment are merited. Testing this hypothesis, the tumor marker, metabolic activity, and overall survival (OS) responses, to the use of one such system, implantable macrobeads [RENCA macrobeads (RMBs)], in phase I and IIa clinical trials in advanced, treatment-resistant metastatic colorectal cancer (mCRC) are described here. METHODS: Forty-eight mCRC patients (30 females; 18 males), who had failed all available, approved treatments, underwent RMB implantation (8 RMB/kg body weight) up to 4 times in phase I and phase IIa open-label trials. Physicals, labs [tumor and inflammation markers, lactate dehydrogenase (LDH)] and positron emission tomography-computed tomography (PET-CT) imaging to measure number/volume and metabolic activity of the tumors were performed pre- and 3-month-post-implantation to evaluate safety and initial efficacy (as defined by biological responses). PET-CT maximum standard uptake value (SUVmax) (baseline and d 90; SUVmax ≥2.5), LDH, and carcinoembryonic antigen (CEA) and/or cancer antigen 19-9 (CA 19-9) response (baseline, d 30 and/or d 60) were assessed and compared to OS. RESULTS: Responses after implantation were characterized by an at least 20% decrease in CEA and/or CA 19-9 in 75% of patients. Fluorodeoxyglucose (FDG)-positive lesions (phase I, 39; 2a, 82) were detected in 37/48 evaluable patients, with 35% stable volume and stable or decreased SUV (10) plus four with necrosis; 10, increased tumor volume, SUV. LDH levels remained stable and low in Responders (R) (d 0-60, 290.4-333.9), but increased steadily in Non-responders (NR) (d 0-60, 382.8-1,278.5) (d 60, P=0.050). Responders to RMBs, indicated by the changes in the above markers, correlated with OS (R mean OS=10.76 months; NR mean OS=4.9 months; P=0.0006). CONCLUSIONS: The correlations of the tumor marker, tumor volume and SUV changes on PET-CT, and LDH levels themselves, and with OS, support the concept of a biological response to RMB implantation and the validity of the biological-systems approach to mCRC. A phase III clinical trial is planned.

13.
Transl Lung Cancer Res ; 4(5): 515-23, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26629420

RESUMEN

In many cancers, including non-small cell lung cancer (NSCLC), tumor angiogenesis pathways have been identified as important therapeutic targets. Angiogenesis is essential in the process of primary tumor growth, proliferation and metastasis. One of the best characterized group of protein factors for angiogenesis include the members of the vascular endothelial growth factor (VEGF) family, consisting of VEGF-(A-D), and placenta growth factor (PIGF). Targeting tumor angiogenesis has been approached through two primary methods, monoclonal antibodies that block VEGF-vascular endothelial growth factor receptor (VEGFR) binding or small molecule tyrosine kinase inhibitors (TKIs) that inhibit the downstream VEGFR mediated signaling. Many TKIs inhibit multiple pro-angiogenic and pro-proliferative pathways such as the mitogen activated protein (MAP) kinase pathway. Bevacizumab and ramucirumab, monoclonal antibodies targeting VEGF and the VEGFR, respectively, have each led to improvements in overall survival (OS) for NSCLC when added to standard first and second line chemotherapy, respectively. Small incremental gains seen with both bevacizumab and ramucirumab may be further improved upon by incorporating novel agents and treatment strategies, and many additional trials are ongoing.

14.
Cancer Control ; 21(3): 221-30, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24955706

RESUMEN

BACKGROUND: Mutations in BRAF were first reported in 2002. Since that time, the molecular basis for oncogenic signaling has been elucidated in multiple malignancies. The development of v-raf murine sarcoma viral oncogene homolog B (BRAF) inhibitors has helped improve clinical outcomes in malignant melanoma and is suggested by case reports in other malignancies. METHODS: A review of pertinent articles examining the mechanisms of BRAF signaling in various cancer types and an update on clinical trials of BRAF inhibitions are presented. RESULTS: Clinical response to BRAF inhibition varies by malignancy. In melanoma, single-agent vemurafenib or dabrafenib prolongs overall survival compared with chemotherapy, but both are limited by the development of acquired resistance in many patients. Results of early-phase clinical trials and case reports demonstrate responses in V600E-mutant non-small-cell lung cancer, thyroid cancer, and hairy cell leukemia. However, no significant difference in progression-free survival was seen in colorectal cancer with single-agent vemurafenib. Overcoming resistance to BRAF inhibition with combination therapy is an active area of research. CONCLUSIONS: The detection of BRAF mutations represents an advance in delivering molecularly targeted therapies to patients with a variety of cancers. Acquired resistance limits the ability of BRAF inhibitors to produce long-term remissions; however, combining BRAF inhibitors with the mitogen-activated protein kinase pathway and/or other pathway inhibitors represents a promising method to improve long-term outcomes.


Asunto(s)
Mutación , Neoplasias/enzimología , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Animales , Humanos , Neoplasias/epidemiología , Neoplasias/genética , Neoplasias/terapia , Transducción de Señal
15.
Cancer Control ; 20(1): 22-31, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23302904

RESUMEN

BACKGROUND: Lung cancer is the most common cause of cancer-related death in the United States, yet traditional chemotherapy fails to provide long-term benefit for many patients. New approaches are needed to improve overall survival beyond the current standard of care. METHODS: This review discusses recent clinical trials using immunotherapy techniques to treat both non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) and highlights ongoing immunotherapy research efforts at our center. RESULTS: For NSCLC, phase II clinical trials have examined allogeneic vaccines that target either mucin 1 (MUC1), epidermal growth factor or melanoma-associated antigen 3. These vaccines are now undergoing larger phase III trials. An autologous cellular therapy directed against transforming growth factor beta-2 and a recombinant protein with antitumor properties have also shown promise in prolonging survival in NSCLC in phase II trials. The monoclonal antibodies ipilimumab, BMS-936558 (anti-PD-1), and BMS936559 (anti-PD-L1) lead to enhanced T-cell-mediated antitumor effects and have produced objective responses in early-phase clinical trials. Studies for SCLC also exist, such as a novel vaccine therapy targeting p53. CONCLUSIONS: Recent clinical trials in lung cancer demonstrate the potential of immunotherapeutics to increase overall survival in patients with lung cancer compared with the current standard of care.


Asunto(s)
Vacunas contra el Cáncer/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/terapia , Inmunoterapia/métodos , Neoplasias Pulmonares/terapia , Anticuerpos Monoclonales/uso terapéutico , Antígenos de Neoplasias/inmunología , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Ensayos Clínicos como Asunto , Factor de Crecimiento Epidérmico/inmunología , Humanos , Ipilimumab , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/mortalidad , Mucina-1/inmunología , Proteínas de Neoplasias/inmunología , Nivolumab , Carcinoma Pulmonar de Células Pequeñas/inmunología , Carcinoma Pulmonar de Células Pequeñas/mortalidad , Carcinoma Pulmonar de Células Pequeñas/terapia , Factor de Crecimiento Transformador beta2/inmunología
16.
Islets ; 3(4): 196-203, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21633194

RESUMEN

Streptozotocin (STZ), a nitrosourea with DNA alkylating properties, has been widely used to induce hyperglycemia by specifically destroying the insulin-producing ß-cells of the islets of Langerhans in experimental models of Type I diabetes. STZ's known carcinogenic properties, however, raise concerns about its suitability for long-term studies. We conducted a formal study of STZ's carcinogenic effects in long-term surviving diabetic Wistar-Furth rats. To determine if insulin therapy or islet transplantation exacerbated tumorigenesis, rats were randomly assigned to one of four experimental groups: normal animals with no treatment (Group 1, n=12); normal animals that underwent peritoneal implantation of porcine islets encapsulated in a double layer of agarose to form islet macrobeads (normal + islets; group 2, n=12); STZ treatment followed by daily exogenous insulin (STZ + insulin; group 3, n=18) and STZ treatment followed by the intraperitoneal implantation of porcine islet macrobeads (STZ + islets; group 4, n=14). At 215 days post-STZ induction, no renal proliferative lesions were observed in animals that did not receive STZ (group 1 and group 2) whereas adenoma incidences of 57% for group 3 and 34% for group 4 were observed. By terminal necropsy at day 351, the incidence and severity of renal proliferative lesions increased with tubular carcinoma observed in 67% of group 3 and 60% of group 4 animals. We conclude that the STZ-induced diabetic rat model is not suitable for long-term studies because of progressive renal tumorigenesis. Our experiments also demonstrate the safety and effectiveness of porcine islet macrobeads for the treatment of diabetes.


Asunto(s)
Cocarcinogénesis , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/cirugía , Insulina/efectos adversos , Trasplante de Islotes Pancreáticos/efectos adversos , Neoplasias Renales/etiología , Estreptozocina/toxicidad , Adenoma/inducido químicamente , Adenoma/etiología , Adenoma/patología , Animales , Carcinógenos/toxicidad , Carcinoma de Células Renales/inducido químicamente , Carcinoma de Células Renales/etiología , Carcinoma de Células Renales/patología , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Trasplante de Islotes Pancreáticos/métodos , Neoplasias Renales/inducido químicamente , Neoplasias Renales/patología , Masculino , Distribución Aleatoria , Ratas , Ratas Endogámicas WF , Sefarosa/efectos adversos , Sus scrofa , Andamios del Tejido/efectos adversos , Trasplante Heterólogo , Trasplante Heterotópico
17.
Cancer Res ; 71(3): 725-35, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21266362

RESUMEN

Cancer cells and their associated tumors have long been considered to exhibit unregulated proliferation or growth. However, a substantial body of evidence indicates that tumor growth is subject to both positive and negative regulatory controls. Here, we describe a novel property of tumor growth regulation that is neither species nor tumor-type specific. This property, functionally a type of feedback control, is triggered by the encapsulation of neoplastic cells in a growth-restricting hydrogel composed of an agarose matrix with a second coating of agarose to form 6- to 8-mm diameter macrobeads. In a mouse cell model of renal adenocarcinoma (RENCA cells), this process resulted in selection for a stem cell-like subpopulation which together with at least one other cell subpopulation drove colony formation in the macrobeads. Cells in these colonies produced diffusible substances that markedly inhibited in vitro and in vivo proliferation of epithelial-derived tumor cells outside the macrobeads. RENCA cells in monolayer culture that were exposed to RENCA macrobead-conditioned media exhibited cell-cycle accumulation in S phase due to activation of a G(2)/M checkpoint. At least 10 proteins with known tumor suppression functions were identified by analysis of RENCA macrobead-conditioned media, the properties of which offer opportunities to further dissect the molecular basis for tumor growth control. More generally, macrobead culture may permit the isolation of cancer stem cells and other cells of the stem cell niche, perhaps providing strategies to define more effective biologically based clinical approaches to treat neoplastic disease.


Asunto(s)
Carcinoma de Células Renales/patología , Técnicas de Cultivo de Célula/métodos , Neoplasias Renales/patología , Animales , Ciclo Celular/fisiología , Procesos de Crecimiento Celular/fisiología , Línea Celular Tumoral , Técnicas de Cocultivo , Células HCT116 , Humanos , Ratones , Ratones Endogámicos BALB C , Sefarosa , Especificidad de la Especie
18.
Cancer Res ; 71(3): 716-24, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21266363

RESUMEN

The culture of tumor cell lines in three-dimensional scaffolds is considered to more closely replicate the in vivo tumor microenvironment than the standard method of two-dimensional cell culture. We hypothesized that our method of encapsulating and maintaining viable and functional pancreatic islets in agarose-agarose macrobeads (diameter 6-8 mm) might provide a novel method for the culture of tumor cell lines. In this report we describe and characterize tumor colonies that form within macrobeads seeded with mouse renal adenocarcinoma cells. Approximately 1% of seeded tumor cells survive in the macrobead and over several months form discrete elliptical colonies appearing as tumor cell niches with increasing metabolic activity in parallel to colony size. The tumor colonies demonstrate ongoing cell turnover as shown by BrdU incorporation and activated caspase-3 and TUNEL staining. Genes upregulated in the tumor colonies of the macrobead are likely adaptations to this novel environment, as well as an amplification of G(1)/S cell-cycle checkpoints. The data presented, including SCA-1 and Oct4 positivity and the upregulation of stem cell-like genes such as those associated with the Wnt pathway, support the notion that the macrobead selects for a subpopulation of cells with cancer stem cell or cancer progenitor properties.


Asunto(s)
Carcinoma de Células Renales/patología , Técnicas de Cultivo de Célula/métodos , Neoplasias Renales/patología , Células Madre Neoplásicas/patología , Animales , Apoptosis/fisiología , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Procesos de Crecimiento Celular , Línea Celular Tumoral , Técnicas de Cocultivo , Expresión Génica , Humanos , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Ratones , Ratones Endogámicos BALB C , Células Madre Neoplásicas/metabolismo , Sefarosa , Células Tumorales Cultivadas
19.
Cell Transplant ; 14(7): 427-39, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16285251

RESUMEN

For clinical xenogenic islet transplantation to be successful, several requirements must be met. Among them is a sizeable and reliable source of fully functional and microbiologically safe islets. The inherent variability among porcine pancreases, with respect to islet yield, prompted us to develop a Biopsy Score technique to determine the suitability of each pancreas for islet isolation processing. The Biopsy Score consists of an assessment of five variables: warm ischemia time, pancreas color, fat content, islet size, and islet demarcation, each of which is assigned a value of -1 or +1, depending on whether or not the established criteria is met. For determination of islet size and demarcation, fresh biopsies of porcine pancreases are stained with dithizone (DTZ) solution and examined under a dissecting microscope. Based on the scoring of such biopsies in pancreases from 26-56-month-old sows, we report here that the presence of large (>100 microm diameter), well-demarcated islets in the pancreas biopsy is a reliable predictor of isolation success. Encapsulation of the isolated porcine islets within the inner layer of a 1.5% agarose and an outer layer of 5.0% agarose macrobead, containing 500 equivalent islet number (EIN), provides for extended in vitro functional viability (>6 months of insulin production in response to glucose), as well as for comprehensive microbiological testing and at least partial isolation of the xenogeneic islets from the host immune system. All microbiological testing to date has been negative, except for the presence of porcine endogenous retrovirus (PERV). Taken together, we believe that the Biopsy Score enhancement of our islet isolation technique and our agarose-agarose macroencapsulation methodology bring us significantly closer to realizing clinical porcine islet xenotransplantation for the treatment of insulin-dependent diabetic patients.


Asunto(s)
Trasplante de Islotes Pancreáticos/normas , Islotes Pancreáticos/citología , Islotes Pancreáticos/microbiología , Páncreas/citología , Técnicas de Cultivo de Tejidos/métodos , Animales , Cápsulas , Islotes Pancreáticos/química , Trasplante de Islotes Pancreáticos/métodos , Masculino , Ratones , Páncreas/química , Páncreas/patología , Seguridad , Porcinos , Supervivencia Tisular
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