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INTRODUCTION: Cancer stem cells (CSCs) are a theorized subset of cells within the tumor that is thought to drive disease recurrence and metastatic spread. The aim of this study is to investigate mRNA and protein levels of ganglioside GD2 synthase (GD2S), in breast cancer (BC) patients. METHODS: 65 PBMCs of preoperative BC patients without chemotherapy were compared to PBMCs after chemotherapy and controls. RESULTS: GD2S were significantly higher in BC patients after chemotherapy compared to pre-chemotherapy at both mRNA and protein. GD2S was higher in pre-chemotherapy blood samples compared to control samples. CONCLUSIONS: Higher expression of GD2S in BC samples compared to healthy control indicates the potential utility of GD2S as a marker of malignancy.
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Neoplasias de la Mama , N-Acetilgalactosaminiltransferasas , Recurrencia Local de Neoplasia , Células Madre Neoplásicas , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Femenino , Humanos , N-Acetilgalactosaminiltransferasas/sangre , Recurrencia Local de Neoplasia/metabolismo , Células Madre Neoplásicas/enzimología , Células Madre Neoplásicas/metabolismo , ARN Mensajero/metabolismoRESUMEN
Detection of circulating tumor cells (CTCs) relying on their expression of epithelial cell markers, such as epithelial cell adhesion molecule (EpCAM), has been commonly used. However, this approach unlikely captures CTCs that have undergone the process of epithelial-mesenchymal transition (EMT). In this study, we have induced EMT of in vitro prostate (PCa) and breast cancer (BCa) cell lines by treatment of transforming growth factor ß 1 (TGFß1), a pleiotropic cytokine with transition-regulating activities. We found that the TGFß1-treated, post-EMT cells exhibited up to a 45% reduction in binding affinity to antibodies against EpCAM (aEpCAM). To overcome this limitation, we designed our capture platform that integrates a unique combination of biomimetic cell rolling, dendrimer-mediated multivalent binding, and antibody cocktails of aEpCAM/aEGFR/aHER-2. Our capture surfaces resulted in up to 98% capture efficiency of post-EMT cells from mixtures of TGFß1-treated and untreated cancer cells spiked in culture media and human blood. In a clinical pilot study, our CTC device was also able to capture rare CTCs from PCa patients with significantly enhanced capture sensitivity and purity compared to the control surface with aEpCAM only, demonstrating its potential to provide a reliable detection solution for CTCs regardless of their EMT status.
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Neoplasias de la Mama/patología , Separación Celular/métodos , Dendrímeros/química , Transición Epitelial-Mesenquimal , Células Neoplásicas Circulantes/patología , Neoplasias de la Próstata/patología , Factor de Crecimiento Transformador beta1/administración & dosificación , Neoplasias de la Mama/sangre , Proliferación Celular , Molécula de Adhesión Celular Epitelial/química , Molécula de Adhesión Celular Epitelial/metabolismo , Femenino , Humanos , Masculino , Células Neoplásicas Circulantes/efectos de los fármacos , Células Neoplásicas Circulantes/metabolismo , Proyectos Piloto , Neoplasias de la Próstata/sangre , Células Tumorales CultivadasRESUMEN
We numerically solve a generalized nonlinear Schrödinger equation and find a family of pure-quartic solitons (PQSs), existing through a balance of positive Kerr nonlinearity and negative quartic dispersion. These solitons have oscillatory tails, which can be understood analytically from the properties of linear waves with quartic dispersion. By computing the linear eigenspectrum of the solitons, we show that they are stable, but that they possess a nontrivial internal mode close to the radiation continuum. We also demonstrate evolution into a PQS from Gaussian initial conditions. The energy-width scaling of PQSs differs strongly from that for conventional solitons, opening up possibilities for PQS lasers.
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The semaphorins represent a large family of signaling molecules with crucial roles in neuronal and cardiac development. While normal semaphorin function pertains largely to development, their involvement in malignancy is becoming increasingly evident. One member, Semaphorin 3C (SEMA3C), has been shown to drive a number of oncogenic programs, correlate inversely with cancer prognosis, and promote the progression of multiple different cancer types. This report surveys the body of knowledge surrounding SEMA3C as a therapeutic target in cancer. In particular, we summarize SEMA3C's role as an autocrine andromedin in prostate cancer growth and survival and provide an overview of other cancer types that SEMA3C has been implicated in including pancreas, brain, breast, and stomach. We also propose molecular strategies that could potentially be deployed against SEMA3C as anticancer agents such as biologics, small molecules, monoclonal antibodies and antisense oligonucleotides. Finally, we discuss important considerations for the inhibition of SEMA3C as a cancer therapeutic agent.
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Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Próstata/efectos de los fármacos , Neoplasias de la Próstata/tratamiento farmacológico , Semaforinas/farmacología , Semaforinas/uso terapéutico , Animales , Proliferación Celular/efectos de los fármacos , Humanos , MasculinoRESUMEN
BACKGROUND: LIM and SH3 domain protein 1 (LASP1) has been implicated in several human malignancies and has been shown to predict PSA recurrence in prostate cancer. However, the anti-tumor effect of LASP1 knockdown and the association between LASP1 and the androgen receptor (AR) remains unclear. The aim of this study is to clarify the significance of LASP1 as a target for prostate cancer, and to test the effect of silencing LASP1 in vivo using antisense oligonucleotides (ASO). METHODS: A tissue microarray (TMA) was performed to characterize the differences in LASP1 expression in prostate cancer treated after hormone deprivation therapy. Flow cytometry was used to analyze cell cycle. We designed LASP1 ASO for knockdown of LASP1 in vivo studies. RESULTS: The expression of LASP1 in TMA was increased after androgen ablation and persisted in castration resistant prostate cancer (CRPC). Also in TMA, compared with LNCaP cell, LASP1 expression is elevated in CRPC cell lines (C4-2 and VehA cells). Interestingly, suppression of AR elevated LASP1 expression conversely, AR activation decreased LASP1 expression. Silencing of LASP1 reduced cell growth through G1 arrest which was accompanied by a decrease of cyclin D1. Forced overexpression of LASP1 promoted cell cycle and induced cell growth which was accompanied by an increase of cyclin D1. Systemic administration of LASP1 ASO with athymic mice significantly inhibited tumor growth in CRPC xenografts. CONCLUSIONS: These results indicate that LASP1 is negatively regulated by AR at the transcriptional level and promotes tumor growth through induction of cell cycle, ultimately suggesting that LASP1 may be a potential target in prostate cancer treatment. Prostate 77:309-320, 2017. © 2016 Wiley Periodicals, Inc.
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Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Proteínas del Citoesqueleto/antagonistas & inhibidores , Proteínas del Citoesqueleto/biosíntesis , Progresión de la Enfermedad , Proteínas con Dominio LIM/antagonistas & inhibidores , Proteínas con Dominio LIM/biosíntesis , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Receptores Androgénicos/biosíntesis , Proteínas Adaptadoras Transductoras de Señales/genética , Antagonistas de Andrógenos/farmacología , Antagonistas de Andrógenos/uso terapéutico , Animales , Proteínas del Citoesqueleto/genética , Técnicas de Silenciamiento del Gen/métodos , Humanos , Proteínas con Dominio LIM/genética , Masculino , Ratones , Ratones Desnudos , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Receptores Androgénicos/genéticaRESUMEN
The lack of an effective detection method for lung circulating tumor cells (CTCs) presents a substantial challenge to elucidate the value of CTCs as a diagnostic or prognostic indicator in lung cancer, particularly in nonsmall cell lung cancer (NSCLC). In this study, we prepared a capture surface exploiting strong multivalent binding mediated by poly(amidoamine) (PAMAM) dendrimers to capture CTCs originating from lung cancers. Given that 85% of the tumor cells from NSCLC patients overexpress epidermal growth factor receptor (EGFR), anti-EGFR was chosen as a capture agent. Following in vitro confirmation using the murine lung cancer cell lines (ED-1 and ED1-SC), cyclin E-overexpressing (CEO) transgenic mice were employed as an in vivo lung tumor model to assess specificity and sensitivity of the capture surface. The numbers of CTCs in blood from the CEO transgenic mice were significantly higher than those from the healthy controls (on average 75.3 ± 14.9 vs 4.4 ± 1.2 CTCs/100 µL of blood, p < 0.005), indicating the high sensitivity and specificity of our surface. Furthermore, we found that the capture surface also offers a simple, effective method for monitoring treatment responses, as observed by the significant decrease in the CTC numbers from the CEO mice upon a treatment using a novel anti-miR-31 locked nucleic acid (LNA), compared to a vehicle treatment and a control-LNA treatment (p < 0.05). This in vivo evaluation study confirms that our capture surface is highly efficient in detecting in vivo CTCs and thus has translational potential as a diagnostic and prognostic tool for lung cancer.
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Anticuerpos Inmovilizados/química , Carcinoma de Pulmón de Células no Pequeñas/patología , Dendrímeros/química , Receptores ErbB/análisis , Neoplasias Pulmonares/patología , Células Neoplásicas Circulantes/patología , Poliaminas/química , Animales , Carcinoma de Pulmón de Células no Pequeñas/sangre , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Recuento de Células , Línea Celular Tumoral , Separación Celular/métodos , Humanos , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/diagnóstico , Ratones , Ratones Transgénicos , Pronóstico , Propiedades de SuperficieRESUMEN
A major limitation of gene therapy for sickle cell disease (SCD) is the availability and access to a potentially curative one-time treatment, due to high treatment costs. We have developed a high-titer bifunctional lentiviral vector (LVV) in a vector backbone that has reduced size, high vector yields, and efficient gene transfer to human CD34+ hematopoietic stem and progenitor cells (HSPCs). This LVV contains locus control region cores expressing an anti-sickling ßAS3-globin gene and two microRNA-adapted short hairpin RNA simultaneously targeting BCL11A and ZNF410 transcripts to maximally induce fetal hemoglobin (HbF) expression. This LVV induces high levels of anti-sickling hemoglobins (HbAAS3 + HbF), while concurrently decreasing sickle hemoglobin (HbS). The decrease in HbS and increased anti-sickling hemoglobin impedes deoxygenated HbS polymerization and red blood cell sickling at low vector copy per cell in transduced SCD patient CD34+ cells differentiated into erythrocytes. The dual alterations in red cell hemoglobins ameliorated the SCD phenotype in the SCD Berkeley mouse model in vivo. With high titer and enhanced transduction of HSPC at a low multiplicity of infection, this LVV will increase the number of patient doses of vector from production lots to decrease costs and help improve accessibility to gene therapy for SCD.
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FOXA1 is a pioneer transcription factor that is frequently mutated in prostate, breast, bladder, and salivary gland malignancies. Indeed, metastatic castration-resistant prostate cancer (mCRPC) commonly harbour FOXA1 mutations with a prevalence of 35%. However, despite the frequent recurrence of FOXA1 mutations in prostate cancer, the mechanisms by which FOXA1 variants drive its oncogenic effects are still unclear. Semaphorin 3C (SEMA3C) is a secreted autocrine growth factor that drives growth and treatment resistance of prostate and other cancers and is known to be regulated by both AR and FOXA1. In the present study, we characterize FOXA1 alterations with respect to its regulation of SEMA3C. Our findings reveal that FOXA1 alterations lead to elevated levels of SEMA3C both in prostate cancer specimens and in vitro. We further show that FOXA1 negatively regulates SEMA3C via intronic cis elements, and that mutations in FOXA1 forkhead domain attenuate its inhibitory function in reporter assays, presumably by disrupting DNA binding of FOXA1. Our findings underscore the key role of FOXA1 in prostate cancer progression and treatment resistance by regulating SEMA3C expression and suggest that SEMA3C may be a driver of growth and tumor vulnerability of mCRPC harboring FOXA1 alterations.
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Factor Nuclear 3-alfa del Hepatocito , Neoplasias de la Próstata Resistentes a la Castración , Semaforinas , Humanos , Masculino , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Factor Nuclear 3-alfa del Hepatocito/genética , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Mutación , Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/patología , Factores de Transcripción/metabolismo , Semaforinas/genética , Semaforinas/metabolismoRESUMEN
Post-acne scarring is a common consequence of acne vulgaris with no universal cure. Although there have been many recent advances to address acne scars physically, there is still a lack of research that investigates their psychosocial impacts. Our comprehensive PubMed search presents an overview of existing information to highlight known sources of mental distress caused by post-acne scarring, both related to and independent of the psychosocial detriments caused early on by active acne. The literature indicates that acne scarring is a distinct condition from acne vulgaris and therefore requires a comprehensive clinical approach unique from those available for active acne.
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Subcutaneous incisionless surgery, also known as subcision, is a minimally invasive procedure that is commonly indicated for the treatment of atrophic acne scars. In recent years, many new techniques have been developed to maximize results from this procedure. This review article aims to identify an updated list of instruments and combinatorial treatments available for atrophic acne scar patients undergoing subcision. We constructed a comprehensive PubMed search term and performed triple-blinded screening on all resulting studies for mentions of subcision as indicated by acne scarring. Our results show that there are four main categories of subcision tools that are commonly employed to treat atrophic acne scars: needles, cannulas, wires, and blunt-blade instruments. Usage of these devices varies by scar depth, personal preference, and combinatorial treatment options. Overall, subcision is a particularly effective treatment for atrophic acne scars, and there is vast potential for further innovation with this technique.
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Intratumoral androgen biosynthesis contributes to castration-resistant prostate cancer progression in patients treated with androgen deprivation therapy. The molecular mechanisms by which castration-resistant prostate cancer acquires the capacity for androgen biosynthesis to bypass androgen deprivation therapy are not entirely known. Here, we show that semaphorin 3C, a secreted signaling protein that is highly expressed in castration-resistant prostate cancer, can promote steroidogenesis by altering the expression profile of key steroidogenic enzymes. Semaphorin 3C not only upregulates enzymes required for androgen synthesis from dehydroepiandrosterone or de novo from cholesterol but also simultaneously downregulates enzymes involved in the androgen inactivation pathway. These changes in gene expression correlate with increased production of androgens induced by semaphorin 3C in prostate cancer model cells. Moreover, semaphorin 3C upregulates androgen synthesis in LNCaP cell-derived xenograft tumors, likely contributing to the enhanced in vivo tumor growth rate post castration. Furthermore, semaphorin 3C activates sterol regulatory element-binding protein, a transcription factor that upregulates enzymes involved in the synthesis of cholesterol, a sole precursor for de novo steroidogenesis. The ability of semaphorin 3C to promote intratumoral androgen synthesis may be a key mechanism contributing to the reactivation of the androgen receptor pathway in castration-resistant prostate cancer, conferring continued growth under androgen deprivation therapy. These findings identify semaphorin 3C as a potential therapeutic target for suppressing intratumoral steroidogenesis.
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Neoplasias de la Próstata Resistentes a la Castración , Semaforinas , Masculino , Humanos , Andrógenos/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Antagonistas de Andrógenos , Receptores Androgénicos/metabolismo , Colesterol/metabolismo , Semaforinas/genética , Semaforinas/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión GénicaRESUMEN
Scarring is a dire consequence of acne vulgaris. Particularly, atrophic acne scarring is highly prevalent among young adults, and its physical and psychological effects can persist throughout their lives if left untreated. This literature review will analyze various non-energy-based approaches to treating atrophic acne scarring, emphasizing recent advances within the last 5 to 10 years. To accomplish this, we performed a PubMed search for various acne scar treatments such as chemical peels, dermabrasion, microdermabrasion, subcision, microneedling, punch techniques, dermal fillers, and thread lifting. Our findings and analysis show that there is no panacean solution to treating atrophic acne scars, which explains the evolving trend towards developing unique combinatorial treatments. Although a fair comparison of each treatment approach is difficult to achieve due to the studies' varying sample sizes, strength of evidence, treatment execution, etc, there still remains a level of consensus on what treatments are well suited for particular scar types.
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Lentiviral vectors (LVs) are robust delivery vehicles for gene therapy as they can efficiently integrate transgenes into host cell genomes. However, LVs with lengthy or complex expression cassettes typically are produced at low titers and have reduced gene transfer capacity, creating barriers for clinical and commercial applications. Modifications of the packaging cell line and methods may be able to produce complex vectors at higher titer and infectivity and may improve production of many different LVs. In this study, we identified two host restriction factors in HEK293T packaging cells that impeded LV production, 2'-5'-oligoadenylate synthetase 1 (OAS1) and low-density lipoprotein receptor (LDLR). Knocking out these two genes separately led to â¼2-fold increases in viral titer. We created a monoclonal cell line, CRISPRed HEK293T to Disrupt Antiviral Response (CHEDAR), by successively knocking out OAS1, LDLR, and PKR, a previously identified factor impeding LV titers. Packaging in CHEDAR yielded â¼7-fold increases in physical particles, full-length vector RNA, and vector titers. In addition, overexpressing transcription elongation factors, SPT4 and SPT5, during packaging improved the production of full-length vector RNA, thereby increasing titers by â¼2-fold. Packaging in CHEDAR with over-expression of SPT4 and SPT5 led to â¼11-fold increases of titers. These approaches improved the production of a variety of LVs, especially vectors with low titers or with internal promoters in the reverse orientation, and may be beneficial for multiple gene therapy applications.
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Cancer stem cells (CSCs) are thought to be a major player in tumor initiation, progression, and metastasis. Targeting CSCs for elimination presents a promising therapeutic strategy; however, this approach will require a stronger understanding of CSC biology and identification of CSC-specific markers. The present study was conducted to examine the correlation between DCLK1 and miR-137 and miR-15a levels in colorectal cancer. A total of 222 samples, including 181 colorectal cancer specimens, 24 adenomatosis, and 17 non-adenomatosis colonic polyps, were stained for DCLK1 expression using immunohistochemistry. Also, expression of miR-137 and miR-15a was assessed in colorectal cancer with high and low DCLK1 expression levels. Most colorectal cancer specimens (76%) showed strong expression of DCLK1, whereas only 21% of adenomatous and none of non-adenomatous colonic polyps showed strong DCLK1 expression. A significant difference in DCLK1 expression was found between colorectal cancer, adenomatous, and non-adenomatous colonic polyps (P < 0.001). Higher expression of DCLK1 was more frequently detected in colorectal cases with larger tumor size (P = 0.03), poor differentiation (P = 0.03), and lymph node involvement (P = 0.04). Comparison of miR-137 and miR-15a in colorectal cancer cases revealed a significant inverse correlation with DCLK1 expression (P = 0.03 and P = 0.04, respectively). DCLK1 may act as a candidate marker for colorectal cancer stem cells. The critical role of DCLK1 in colorectal cancer suggests that it may represent an early diagnostic marker and therapeutic target; however, further investigation is warranted.
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Biomarcadores de Tumor/metabolismo , Neoplasias Colorrectales/patología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , MicroARNs/genética , Células Madre Neoplásicas/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Progresión de la Enfermedad , Quinasas Similares a Doblecortina , Femenino , Estudios de Seguimiento , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Células Madre Neoplásicas/metabolismo , Pronóstico , Proteínas Serina-Treonina Quinasas/genéticaRESUMEN
Lentiviral vectors (LVs) commonly used for the treatment of hemoglobinopathies often have low titers and sub-optimal gene transfer efficiency for human hematopoietic stem and progenitor cells (HSPCs), hindering clinical translation and commercialization for ex vivo gene therapy. We observed that a high percentage of ß-globin LV viral genomic RNAs were incomplete toward the 3' end in packaging cells and in released vector particles. The incomplete vector genomes impeded reverse transcription in target cells, limiting stable gene transfer to HSPCs. By combining three modifications to vector design and production (shortening the vector length to 5.3 kb; expressing HIV-1 Tat protein during packaging; and packaging in PKR-/- cells) there was a 30-fold increase in vector titer and a 3-fold increase in vector infectivity in HSPCs. These approaches may improve the manufacturing of ß-globin and other complex LVs for enhanced gene delivery and may facilitate clinical applications.
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Vectores Genéticos/metabolismo , Lentivirus/genética , ARN/metabolismo , Virión/fisiología , Globinas beta/genética , Técnicas de Transferencia de Gen , Vectores Genéticos/genética , Células HEK293 , Humanos , Globinas beta/metabolismo , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/metabolismoRESUMEN
The putative cardioprotective and chemopreventive properties of the red wine phenolic resveratrol (RES) have made it the subject of a growing body of clinical and basic research. We have begun investigations focusing on the effects of RES on the activity of the aryl hydrocarbon receptor (AHR) complex. Our evidence suggests that RES is a potent repressor of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-inducible gene transcription in estrogen receptor (ER)-positive human breast, lung, and colon cancer cell lines. RES activates the transcription of the ER target genes to the same degree as estradiol (E(2)) in human MCF-7 breast cancer cells. Unlike E(2), which can only diminish TCDD-inducible CYP1A1 gene transcription by approximately 50%, RES can completely abrogate this response. Furthermore, 50% repression of TCDD-inducible transcription can be achieved with 100 nM RES, approximately 2.5 orders of magnitude lower than concentrations required for maximal inhibition, suggesting that multiple mechanisms are responsible for this effect. RES (100 nM) does not prevent ligand binding of a TCDD analog, nor does it prevent AHR from binding to its response element in the 5'-regulatory region of the CYP1A1 gene. Small inhibitory RNAs directed to ERα have demonstrated that RES-mediated repression of CYP1A1 depends on ERα. Whereas CYP1A1 protein levels in MCF-7 cells are refractory to the low-dose transcriptional effects of RES, a concomitant decrease in CYP1A1 protein levels is observed in Caco-2 cells. These results highlight a low-dose RES effect that could occur at nutritionally relevant exposures and are distinct from the high-dose effects often characterized.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/antagonistas & inhibidores , Citocromo P-450 CYP1A1/antagonistas & inhibidores , Receptor alfa de Estrógeno/biosíntesis , Sustancias Protectoras/farmacología , Receptores de Hidrocarburo de Aril/antagonistas & inhibidores , Estilbenos/farmacología , Unión Competitiva , Western Blotting , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Citocromo P-450 CYP1A1/genética , Relación Dosis-Respuesta a Droga , Receptor alfa de Estrógeno/genética , Expresión Génica/efectos de los fármacos , Humanos , Ligandos , Regiones Promotoras Genéticas/efectos de los fármacos , Sustancias Protectoras/administración & dosificación , Unión Proteica , Interferencia de ARN , Ensayo de Unión Radioligante , Resveratrol , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estilbenos/administración & dosificaciónRESUMEN
Oxidative stress induced by lipid peroxidation products (LPP) accompanies aging and has been hypothesized to exacerbate the secondary cascade in traumatic brain injury (TBI). Increased oxidative stress is a contributor to loss of neural reserve that defines the ability to maintain healthy cognitive function despite the accumulation of neuropathology. ALDH2-/- mice are unable to clear aldehyde LPP by mitochondrial aldehyde dehydrogenase-2 (Aldh2) detoxification and provide a model to study mild TBI (mTBI), therapeutic interventions, and underlying mechanisms. The ALDH2-/- mouse model presents with elevated LPP-mediated protein modification, lowered levels of PSD-95, PGC1-α, and SOD-1, and mild cognitive deficits from 4 months of age. LPP scavengers are neuroprotective in vitro and in ALDH2-/- mice restore cognitive performance. A single-hit, closed skull mTBI failed to elicit significant effects in WT mice; however, ALDH2-/- mice showed a significant inflammatory cytokine surge in the ipsilateral hemisphere 24 h post-mTBI, and increased GFAP cleavage, a biomarker for TBI. Known neuroprotective agents, were able to reverse the effects of mTBI. This new preclinical model of mTBI, incorporating significant perturbations in behavior, inflammation, and clinically relevant biomarkers, allows mechanistic study of the interaction of LPP and neurotrauma in loss of neural reserve.
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Conmoción Encefálica , Fármacos Neuroprotectores , Aldehído Deshidrogenasa Mitocondrial/genética , Animales , Modelos Animales de Enfermedad , Ratones , Estrés OxidativoRESUMEN
Cancer stem cells (CSCs) are a theorized small subpopulation of cells within tumors thought to be responsible for metastasis, tumor development, disease progression, treatment-resistance, and recurrence. The identification, isolation, and biological characterization of CSCs may therefore facilitate the development of efficient therapeutic strategies targeting CSCs. This study aims to compare the biology and telomerase activity of CSCs to parental cells (PCs) in renal cancer. Renal CSCs were enriched from the ACHN cell line using a sphere culture system. Spheroid-derived cells (SDCs) and their adherent counterparts were compared with respect to their colony and sphere formation, expression of putative CSC markers, tumorigenicity in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, and invasiveness. The expression of genes associated with CSCs, stemness, EMT, apoptosis, and ABC transporters was also compared between the two populations using quantitative real-time PCR (qRT-PCR). Finally, telomerase activity, hTERT expression, and sensitivity to MST-312, a telomerase inhibitor, was investigated between the two populations. We demonstrated that a subpopulation of ACHN cells was capable of growing as spheroids with many properties similar to CSCs, including higher clonogenicity, superior colony- and sphere-forming ability, and stronger tumorigenicity and invasiveness. In addition, SDCs demonstrated a higher expression of markers for CSCs, stemness, EMT, apoptosis, and ABC transporter genes compared to PCs. The expression of hTERT and telomerase activity in SDCs was significantly lower than PCs; however, the SDC population was more sensitive to MST-312 compared to PCs. These findings indicate that the SDC population exhibits stem-like potential and invasive characteristics. Moreover, the reduced expression of hTERT and telomerase activity in SDCs demonstrated that the expressions of hTERT and telomerase activity are not always higher in CSCs. Our results also showed that MST-312 treatment inhibited SDCs more strongly than PCs and may therefore be useful as a complementary targeted therapy against renal CSCs in the future.
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The androgen receptor (AR) is a hormone-activated transcription factor that regulates the development and progression of prostate cancer (PCa) and represents one of the most well-established drug targets. Currently clinically approved small molecule inhibitors of AR, such as enzalutamide, are built upon a common chemical scaffold that interacts with the AR by the same mechanism of action. These inhibitors eventually fail due to the emergence of drug-resistance in the form of AR mutations and expression of truncated AR splice variants (e.g. AR-V7) that are constitutively active, signalling the progression of the castration-resistant state of the disease. The urgent need therefore continues for novel classes of AR inhibitors that can overcome drug resistance, especially since AR signalling remains important even in late-stage advanced PCa. Previously, we identified a collection of 10-benzylidene-10H-anthracen-9-ones that effectively inhibit AR transcriptional activity, induce AR degradation and display some ability to block recruitment of hormones to the receptor. In the current work, we extended the analysis of the lead compounds, and used methods of both ligand- and structure-based drug design to develop a panel of novel 10-benzylidene-10H-anthracen-9-one derivatives capable of suppressing transcriptional activity and protein expression levels of both full length- and AR-V7 truncated forms of human androgen receptor. Importantly, the developed compounds efficiently inhibited the growth of AR-V7 dependent prostate cancer cell-lines which are completely resistant to all current anti-androgens.
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Antagonistas de Andrógenos/farmacología , Variación Genética/genética , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Antagonistas de Andrógenos/síntesis química , Antagonistas de Andrógenos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células HEK293 , Humanos , Modelos Moleculares , Estructura Molecular , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-ActividadRESUMEN
Prostate cancer (PCa) is a leading cause of death for men in North America. The androgen receptor (AR) - a hormone inducible transcription factor - drives expression of tumor promoting genes and represents an important therapeutic target in PCa. The AR is activated by steroid recruitment to its ligand binding domain (LBD), followed by receptor nuclear translocation and dimerization via the DNA binding domain (DBD). Clinically used small molecules interfere with steroid recruitment and prevent AR-driven tumor growth, but are rendered ineffective by emergence of LBD mutations or expression of constitutively active variants, such as ARV7, that lack the LBD. Both drug-resistance mechanisms confound treatment of this 'castration resistant' stage of PCa (CRPC), characterized by return of AR signalling. Here, we employ computer-aided drug-design to develop small molecules that block the AR-DBD dimerization interface, an attractive target given its role in AR activation and independence from the LBD. Virtual screening on the AR-DBD structure led to development of prototypical compounds that block AR dimerization, inhibiting AR-transcriptional activity through a LBD-independent mechanism. Such inhibitors may potentially circumvent AR-dependent resistance mechanisms and directly target CRPC tumor growth.