RESUMEN
Nanoparticle (NP) chemotherapeutics can improve the therapeutic index of chemoradiotherapy (CRT). However, the effect of NP physical properties, such particle size, on CRT is unknown. To address this, we examined the effects of NP size on biodistribution, efficacy and toxicity in CRT. PEG-PLGA NPs (50, 100, 150 nm mean diameters) encapsulating wotrmannin (wtmn) or KU50019 were formulated. These NP formulations were potent radiosensitizers in vitro in HT29, SW480, and lovo rectal cancer lines. In vivo, the smallest particles avoided hepatic and splenic accumulation while more homogeneously penetrating tumor xenografts than larger particles. However, smaller particles were no more effective in vivo. Instead, there was a trend toward enhanced efficacy with medium sized NPs. The smallest KU60019 particles caused more small bowel toxicity than larger particles. Our results showed that particle size significantly affects nanotherapeutics' biodistrubtion and toxicity but does not support the conclusion that smaller particles are better for this clinical application.
Asunto(s)
Quimioradioterapia , Nanopartículas , Androstadienos/farmacocinética , Animales , Xenoinjertos , Humanos , Ratones , Tamaño de la Partícula , Polímeros , Neoplasias del Recto , Distribución Tisular , WortmaninaRESUMEN
BACKGROUND & AIMS: Reserve intestinal stem cells (rISCs) are quiescent/slowly cycling under homeostatic conditions, allowing for their identification with label-retention assays. rISCs mediate epithelial regeneration after tissue damage by converting to actively proliferating stem cells (aISCs) that self renew and demonstrate multipotency, which are defining properties of stem cells. Little is known about the genetic mechanisms that regulate the production and maintenance of rISCs. High expression levels of the transcription factor Sox9 (Sox9(high)) are associated with rISCs. This study investigates the role of SOX9 in regulating the rISC state. METHODS: We used fluorescence-activated cell sorting to isolate cells defined as aISCs (Lgr5(high)) and rISCs (Sox9(high)) from Lgr5(EGFP) and Sox9(EGFP) reporter mice. Expression of additional markers associated with active and reserve ISCs were assessed in Lgr5(high) and Sox9(high) populations by single-cell gene expression analyses. We used label-retention assays to identify whether Sox9(high) cells were label-retatining cells (LRCs). Lineage-tracing experiments were performed in Sox9-CreERT2 mice to measure the stem cell capacities and radioresistance of Sox9-expressing cells. Conditional SOX9 knockout mice and inducible-conditional SOX9 knockout mice were used to determine whether SOX9 was required to maintain LRCs and rISC function. RESULTS: Lgr5(high) and a subset of crypt-based Sox9(high) cells co-express markers of aISC and rISC (Lgr5, Bmi1, Lrig1, and Hopx). LRCs express high levels of Sox9 and are lost in SOX9-knockout mice. SOX9 is required for epithelial regeneration after high-dose irradiation. Crypts from SOX9-knockout mice have increased sensitivity to radiation, compared with control mice, which could not be attributed to impaired cell-cycle arrest or DNA repair. CONCLUSIONS: SOX9 limits proliferation in LRCs and imparts radiation resistance to rISCs in mice.
Asunto(s)
Enterocitos/metabolismo , Mucosa Intestinal/citología , Intestino Delgado/efectos de la radiación , Tolerancia a Radiación/fisiología , Factor de Transcripción SOX9/metabolismo , Células Madre/metabolismo , Animales , Proliferación Celular/fisiología , Enterocitos/efectos de la radiación , Expresión Génica , Proteínas Fluorescentes Verdes/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efectos de la radiación , Intestino Delgado/metabolismo , Ratones , Ratones Noqueados , Complejo Represivo Polycomb 1/metabolismo , Tolerancia a Radiación/genética , Receptores Acoplados a Proteínas G/metabolismo , Regeneración/fisiología , Factor de Transcripción SOX9/genética , Células Madre/citología , Células Madre/efectos de la radiaciónRESUMEN
Standard treatment regimens for the management of patients with refractory splenic marginal zone lymphoma (SMZL) are currently unavailable. Here, we report a case of SMZL, which, after failing multiple therapeutics, demonstrated an impressive clinical response to combined Venetoclax and Velcade (V2), a treatment combination currently being investigated in the setting of refractory multiple myeloma. We also report a unique histopathology and mutational profile that may have important implications for the characterization and prognosis of SMZL.
Asunto(s)
Leucemia Linfocítica Crónica de Células B , Linfoma , Neoplasias del Bazo , Bortezomib/uso terapéutico , Compuestos Bicíclicos Heterocíclicos con Puentes , Humanos , Neoplasias del Bazo/tratamiento farmacológico , Neoplasias del Bazo/patología , SulfonamidasRESUMEN
Myelodysplastic syndromes (MDS) and Waldenstrom's macroglobulinemia (WM) are rarely synchronous. Ineffective myelopoiesis/hematopoiesis with clonal unilineage or multilineage dysplasia and cytopenias characterize MDS. Despite a myeloid origin, MDS can sometimes lead to decreased production, abnormal apoptosis or dysmaturation of B cells, and the development of lymphoma. WM includes bone marrow involvement by lymphoplasmacytic lymphoma (LPL) secreting monoclonal immunoglobulin M (IgM) with somatic mutation (L265P) of myeloid differentiation primary response 88 gene (MYD88) in 80-90%, or various mutations of C-terminal domain of the C-X-C chemokine receptor type 4 (CXCR4) gene in 20-40% of cases. A unique, progressive case of concurrent MDS and WM with several somatic mutations (some unreported before) and a novel balanced reciprocal translocation between chromosomes 10 and 13 is presented below.
Asunto(s)
Linfoma , Síndromes Mielodisplásicos , Macroglobulinemia de Waldenström , Humanos , Inmunoglobulina M/genética , Síndromes Mielodisplásicos/genética , Factor 88 de Diferenciación Mieloide/genética , Translocación Genética , Macroglobulinemia de Waldenström/genéticaRESUMEN
Combination immunotherapy has recently emerged as a powerful cancer treatment strategy. A promising treatment approach utilizes coadministration of antagonistic antibodies to block checkpoint inhibitor receptors, such as antiprogrammed cell death-1 (aPD1), alongside agonistic antibodies to activate costimulatory receptors, such as antitumor necrosis factor receptor superfamily member 4 (aOX40). Optimal T-cell activation is achieved when both immunomodulatory agents simultaneously engage T-cells and promote synergistic proactivation signaling. However, standard administration of these therapeutics as free antibodies results in suboptimal T-cell binding events, with only a subset of the T-cells binding to both aPD1 and aOX40. Here, it is shown that precise spatiotemporal codelivery of aPD1 and aOX40 using nanoparticles (NP) (dual immunotherapy nanoparticles, DINP) results in improved T-cell activation, enhanced therapeutic efficacy, and increased immunological memory. It is demonstrated that DINP elicits higher rates of T-cell activation in vitro than free antibodies. Importantly, it is demonstrated in two tumor models that combination immunotherapy administered in the form of DINP is more effective than the same regimen administered as free antibodies. This work demonstrates a novel strategy to improve combination immunotherapy using nanotechnology.
Asunto(s)
Inmunoterapia , Animales , Anticuerpos , Ratones , Nanopartículas , Neoplasias , Linfocitos TRESUMEN
Metastatic disease remains the primary cause of mortality in cancer patients. Yet the number of available in vitro models to study metastasis is limited by challenges in the recapitulation of the metastatic microenvironment in vitro, and by difficulties in maintaining colonized-tissue specificity in the expansion and maintenance of metastatic cells. Here, we show that decellularized scaffolds that retain tissue-specific extracellular-matrix components and bound signalling molecules enable, when seeded with colorectal cancer cells, the spontaneous formation of three-dimensional cell colonies that histologically, molecularly and phenotypically resemble in vivo metastases. Lung and liver metastases obtained by culturing colorectal cancer cells on, respectively, lung and liver decellularized scaffolds retained their tissue-specific tropism when injected in mice. We also found that the engineered metastases contained signet ring cells, which has not previously been observed ex vivo. A culture system with tissue-specific decellularized scaffolds represents a simple and powerful approach for the study of organ-specific cancer metastases.
Asunto(s)
Técnicas de Cultivo de Célula/métodos , Neoplasias Colorrectales , Metástasis de la Neoplasia , Andamios del Tejido , Células CACO-2 , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/fisiopatología , Células HT29 , Humanos , Metástasis de la Neoplasia/patología , Metástasis de la Neoplasia/fisiopatología , Células Tumorales CultivadasRESUMEN
Novel agents are needed to improve chemoradiotherapy for locally advanced rectal cancer. In this study, we assessed the ability of CRLX101, an investigational nanoparticle-drug conjugate containing the payload camptothecin (CPT), to improve therapeutic responses as compared with standard chemotherapy. CRLX101 was evaluated as a radiosensitizer in colorectal cancer cell lines and murine xenograft models. CRLX101 was as potent as CPT in vitro in its ability to radiosensitize cancer cells. Evaluations in vivo demonstrated that the addition of CRLX101 to standard chemoradiotherapy significantly increased therapeutic efficacy by inhibiting DNA repair and HIF1α pathway activation in tumor cells. Notably, CRLX101 was more effective than oxaliplatin at enhancing the efficacy of chemoradiotherapy, with CRLX101 and 5-fluorouracil producing the highest therapeutic efficacy. Gastrointestinal toxicity was also significantly lower for CRLX101 compared with CPT when combined with radiotherapy. Our results offer a preclinical proof of concept for CRLX101 as a modality to improve the outcome of neoadjuvant chemoradiotherapy for rectal cancer treatment, in support of ongoing clinical evaluation of this agent (LCC1315 NCT02010567). Cancer Res; 77(1); 112-22. ©2016 AACR.
Asunto(s)
Camptotecina/farmacología , Ciclodextrinas/farmacología , Reparación del ADN/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/biosíntesis , Fármacos Sensibilizantes a Radiaciones/farmacología , Neoplasias del Recto/patología , Animales , Western Blotting , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Quimioradioterapia/métodos , Técnica del Anticuerpo Fluorescente , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Nanoconjugados , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Immunotherapy holds tremendous promise for improving cancer treatment. To administer radiotherapy with immunotherapy has been shown to improve immune responses and can elicit the 'abscopal effect'. Unfortunately, response rates for this strategy remain low. Herein we report an improved cancer immunotherapy approach that utilizes antigen-capturing nanoparticles (AC-NPs). We engineered several AC-NP formulations and demonstrated that the set of protein antigens captured by each AC-NP formulation is dependent on the NP surface properties. We showed that AC-NPs deliver tumour-specific proteins to antigen-presenting cells (APCs) and significantly improve the efficacy of αPD-1 (anti-programmed cell death 1) treatment using the B16F10 melanoma model, generating up to a 20% cure rate compared with 0% without AC-NPs. Mechanistic studies revealed that AC-NPs induced an expansion of CD8+ cytotoxic T cells and increased both CD4+T/Treg and CD8+T/Treg ratios (Treg, regulatory T cells). Our work presents a novel strategy to improve cancer immunotherapy with nanotechnology.
Asunto(s)
Antígenos de Neoplasias/inmunología , Inmunoterapia/métodos , Melanoma Experimental/terapia , Nanopartículas/uso terapéutico , Animales , Relación CD4-CD8 , Línea Celular Tumoral , Femenino , Melanoma Experimental/inmunología , Ratones Endogámicos C57BL , Nanomedicina/métodos , Neoplasias/inmunología , Neoplasias/terapia , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Linfocitos T Citotóxicos/inmunologíaRESUMEN
Stem cells reside in 'niches', where support cells provide critical signalling for tissue renewal. Culture methods mimic niche conditions and support the growth of stem cells in vitro. However, current functional assays preclude statistically meaningful studies of clonal stem cells, stem cell-niche interactions, and genetic analysis of single cells and their organoid progeny. Here, we describe a 'microraft array' (MRA) that facilitates high-throughput clonogenic culture and computational identification of single intestinal stem cells (ISCs) and niche cells. We use MRAs to demonstrate that Paneth cells, a known ISC niche component, enhance organoid formation in a contact-dependent manner. MRAs facilitate retrieval of early enteroids for quantitative PCR to correlate functional properties, such as enteroid morphology, with differences in gene expression. MRAs have broad applicability to assaying stem cell-niche interactions and organoid development, and serve as a high-throughput culture platform to interrogate gene expression at early stages of stem cell fate choices.