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1.
bioRxiv ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38617314

RESUMO

How genetic lesions drive cell transformation and whether they can be circumvented without compromising function of non-transformed cells are enduring questions in oncology. Here we show that in mature T cells-in which physiologic clonal proliferation is a cardinal feature- constitutive MYC transcription and Tsc1 loss in mice modeled aggressive human malignancy by reinforcing each other's oncogenic programs. This cooperation was supported by MYC-induced large neutral amino acid transporter chaperone SLC3A2 and dietary leucine, which in synergy with Tsc1 deletion overstimulated mTORC1 to promote mitochondrial fitness and MYC protein overexpression in a positive feedback circuit. A low leucine diet was therapeutic even in late-stage disease but did not hinder T cell immunity to infectious challenge, nor impede T cell transformation driven by constitutive nutrient mTORC1 signaling via Depdc5 loss. Thus, mTORC1 signaling hypersensitivity to leucine as an onco-nutrient enables an onco-circuit, decoupling pathologic from physiologic utilization of nutrient acquisition pathways.

2.
Immunity ; 56(11): 2555-2569.e5, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37967531

RESUMO

Tumors develop by invoking a supportive environment characterized by aberrant angiogenesis and infiltration of tumor-associated macrophages (TAMs). In a transgenic model of breast cancer, we found that TAMs localized to the tumor parenchyma and were smaller than mammary tissue macrophages. TAMs had low activity of the metabolic regulator mammalian/mechanistic target of rapamycin complex 1 (mTORC1), and depletion of negative regulator of mTORC1 signaling, tuberous sclerosis complex 1 (TSC1), in TAMs inhibited tumor growth in a manner independent of adaptive lymphocytes. Whereas wild-type TAMs exhibited inflammatory and angiogenic gene expression profiles, TSC1-deficient TAMs had a pro-resolving phenotype. TSC1-deficient TAMs relocated to a perivascular niche, depleted protein C receptor (PROCR)-expressing endovascular endothelial progenitor cells, and rectified the hyperpermeable blood vasculature, causing tumor tissue hypoxia and cancer cell death. TSC1-deficient TAMs were metabolically active and effectively eliminated PROCR-expressing endothelial cells in cell competition experiments. Thus, TAMs exhibit a TSC1-dependent mTORC1-low state, and increasing mTORC1 signaling promotes a pro-resolving state that suppresses tumor growth, defining an innate immune tumor suppression pathway that may be exploited for cancer immunotherapy.


Assuntos
Células Progenitoras Endoteliais , Proteínas Supressoras de Tumor , Animais , Humanos , Serina-Treonina Quinases TOR/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/genética , Macrófagos Associados a Tumor/metabolismo , Células Progenitoras Endoteliais/metabolismo , Receptor de Proteína C Endotelial , Alvo Mecanístico do Complexo 1 de Rapamicina , Neovascularização Patológica , Mamíferos
3.
J Biomed Opt ; 28(9): 096005, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37720189

RESUMO

Significance: An integrated cellular-resolution optical coherence tomography (OCT) module with near-infrared Raman spectroscopy was developed on the discrimination of various skin cancer cells and normal cells. Micron-level three-dimensional (3D) spatial resolution and the spectroscopic capability on chemical component determination can be obtained simultaneously. Aim: We experimentally verified the effectiveness of morphology, intensity, and spectroscopy features for discriminating skin cells. Approach: Both spatial and spectroscopic features were employed for the discrimination of five types of skin cells, including keratinocytes (HaCaT), the cell line of squamous cell carcinoma (A431), the cell line of basal cell carcinoma (BCC-1/KMC), primary melanocytes, and the cell line of melanoma (A375). The cell volume, compactness, surface roughness, average intensity, and internal intensity standard deviation were extracted from the 3D OCT images. After removing the fluorescence components from the acquired Raman spectra, the entire spectra (600 to 2100 cm-1) were used. Results: An accuracy of 85% in classifying five types of skin cells was achieved. The cellular-resolution OCT images effectively differentiate cancer and normal cells, whereas Raman spectroscopy can distinguish the cancer cells with nearly 100% accuracy. Conclusions: Among the OCT image features, cell surface roughness, internal average intensity, and standard deviation of internal intensity distribution effectively differentiate the cancerous and normal cells. The three features also worked well in sorting the keratinocyte and melanocyte. Using the full Raman spectra, the melanoma and keratinocyte-based cell carcinoma cancer cells can be discriminated effectively.


Assuntos
Carcinoma Basocelular , Melanoma , Neoplasias Cutâneas , Humanos , Tomografia de Coerência Óptica , Análise Espectral Raman , Neoplasias Cutâneas/diagnóstico por imagem , Carcinoma Basocelular/diagnóstico por imagem , Melanoma/diagnóstico por imagem , Aprendizado de Máquina
4.
Chem Commun (Camb) ; 59(71): 10660-10663, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37581279

RESUMO

Piperic acid derivatives were found to affect the islet amyloid polypeptide (IAPP) aggregation process. Structure-activity relationship studies revealed that PAD-13 was an efficient molecular modulator to accelerate IAPP fibril formation by promoting primary and secondary nucleation and reducing its antimicrobial activity.


Assuntos
Anti-Infecciosos , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Polipeptídeo Amiloide das Ilhotas Pancreáticas/farmacologia , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Amiloide/química , Ácidos Graxos Insaturados , Anti-Infecciosos/farmacologia
5.
Nature ; 619(7970): 616-623, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380769

RESUMO

In metazoan organisms, cell competition acts as a quality control mechanism to eliminate unfit cells in favour of their more robust neighbours1,2. This mechanism has the potential to be maladapted, promoting the selection of aggressive cancer cells3-6. Tumours are metabolically active and are populated by stroma cells7,8, but how environmental factors affect cancer cell competition remains largely unknown. Here we show that tumour-associated macrophages (TAMs) can be dietarily or genetically reprogrammed to outcompete MYC-overexpressing cancer cells. In a mouse model of breast cancer, MYC overexpression resulted in an mTORC1-dependent 'winner' cancer cell state. A low-protein diet inhibited mTORC1 signalling in cancer cells and reduced tumour growth, owing unexpectedly to activation of the transcription factors TFEB and TFE3 and mTORC1 in TAMs. Diet-derived cytosolic amino acids are sensed by Rag GTPases through the GTPase-activating proteins GATOR1 and FLCN to control Rag GTPase effectors including TFEB and TFE39-14. Depletion of GATOR1 in TAMs suppressed the activation of TFEB, TFE3 and mTORC1 under the low-protein diet condition, causing accelerated tumour growth; conversely, depletion of FLCN or Rag GTPases in TAMs activated TFEB, TFE3 and mTORC1 under the normal protein diet condition, causing decelerated tumour growth. Furthermore, mTORC1 hyperactivation in TAMs and cancer cells and their competitive fitness were dependent on the endolysosomal engulfment regulator PIKfyve. Thus, noncanonical engulfment-mediated Rag GTPase-independent mTORC1 signalling in TAMs controls competition between TAMs and cancer cells, which defines a novel innate immune tumour suppression pathway that could be targeted for cancer therapy.


Assuntos
Competição entre as Células , Técnicas de Reprogramação Celular , Imunidade Inata , Neoplasias , Macrófagos Associados a Tumor , Animais , Camundongos , Aminoácidos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Competição entre as Células/genética , Competição entre as Células/imunologia , Proteínas Alimentares/farmacologia , Modelos Animais de Doenças , GTP Fosfo-Hidrolases/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo
6.
Trends Cancer ; 7(11): 1010-1019, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34305041

RESUMO

Investigation of cancer as a cell-level disease has led to the development of cancer cell-directed therapies including cytotoxic T lymphocyte (CTL)-based immunotherapy; yet, many patients are refractory to these modalities of cancer treatment and acquired resistance frequently occurs. Of note, cancer environment controls the manifestation of cancerous cell phenotype. Helper T (Th) cells orchestrate immune defense responses targeting cancer cells as well as the tumor microenvironment. Recent studies have shown that in addition to interferon (IFN)-γ-producing Th1 cells, interleukin (IL)-4-producing Th2 cells function as potent anticancer effectors in part by promoting tumor stroma reconfiguration and tumor tissue repair. Such Th cell-mediated tissue-level immunity may be harnessed for novel modalities of cancer environment immunotherapy.


Assuntos
Neoplasias , Células Th1 , Humanos , Neoplasias/terapia , Linfócitos T Citotóxicos , Linfócitos T Auxiliares-Indutores , Células Th2 , Microambiente Tumoral
7.
Cancer Metab ; 9(1): 12, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33762003

RESUMO

BACKGROUND: Fructose is an abundant source of carbon and energy for cells to use for metabolism, but only certain cell types use fructose to proliferate. Tumor cells that acquire the ability to metabolize fructose have a fitness advantage over their neighboring cells, but the proteins that mediate fructose metabolism in this context are unknown. Here, we investigated the determinants of fructose-mediated cell proliferation. METHODS: Live cell imaging and crystal violet assays were used to characterize the ability of several cell lines (RKO, H508, HepG2, Huh7, HEK293T (293T), A172, U118-MG, U87, MCF-7, MDA-MB-468, PC3, DLD1 HCT116, and 22RV1) to proliferate in fructose (i.e., the fructolytic ability). Fructose metabolism gene expression was determined by RT-qPCR and western blot for each cell line. A positive selection approach was used to "train" non-fructolytic PC3 cells to utilize fructose for proliferation. RNA-seq was performed on parental and trained PC3 cells to find key transcripts associated with fructolytic ability. A CRISPR-cas9 plasmid containing KHK-specific sgRNA was transfected in 293T cells to generate KHK-/- cells. Lentiviral transduction was used to overexpress empty vector, KHK, or GLUT5 in cells. Metabolic profiling was done with seahorse metabolic flux analysis as well as LC/MS metabolomics. Cell Titer Glo was used to determine cell sensitivity to 2-deoxyglucose in media containing either fructose or glucose. RESULTS: We found that neither the tissue of origin nor expression level of any single gene related to fructose catabolism determine the fructolytic ability. However, cells cultured chronically in fructose can develop fructolytic ability. SLC2A5, encoding the fructose transporter, GLUT5, was specifically upregulated in these cells. Overexpression of GLUT5 in non-fructolytic cells enabled growth in fructose-containing media across cells of different origins. GLUT5 permitted fructose to flux through glycolysis using hexokinase (HK) and not ketohexokinase (KHK). CONCLUSIONS: We show that GLUT5 is a robust and generalizable driver of fructose-dependent cell proliferation. This indicates that fructose uptake is the limiting factor for fructose-mediated cell proliferation. We further demonstrate that cellular proliferation with fructose is independent of KHK.

8.
Biomaterials ; 272: 120765, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33780686

RESUMO

Ischemic stroke, and the consequent brain cell death, is a common cause of death and disability worldwide. Current treatments that primarily aim to relieve symptoms are relatively inefficient in achieving brain tissue regeneration and functional recovery, and thus novel therapeutic options are urgently needed. Although cell-based therapies have shown promise for treating the infarcted brain, a recurring challenge is the inadequate retention and engraftment of transplanted cells at the target tissue, thereby limiting the ultimate therapeutic efficacy. Here, we show that transplantation of preassembled three-dimensional (3D) spheroids of mesenchymal stem cells (MSCs) and vascular endothelial cells (ECs) results in significantly improved cell retention and survival compared with conventional mixed-cell suspensions. The transplanted 3D spheroids exhibit notable neuroprotective, proneurogenic, proangiogenic and anti-scarring potential as evidenced by clear extracellular matrix structure formation and paracrine factor expression and secretion; this ultimately results in increased structural and motor function recovery in the brain of an ischemic stroke mouse model. Therefore, transplantation of MSCs and ECs using the 3D cell spheroid configuration not only reduces cell loss during cell harvesting/administration but also enhances the resultant therapeutic benefit, thus providing important proof-of-concept for future clinical translation.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Transplante de Células-Tronco Mesenquimais , Acidente Vascular Cerebral , Animais , Isquemia Encefálica/terapia , Células Endoteliais , Camundongos , Esferoides Celulares , Acidente Vascular Cerebral/terapia
9.
Oncogene ; 39(37): 5950-5963, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32778768

RESUMO

TMPRSS2 is an important membrane-anchored serine protease involved in human prostate cancer progression and metastasis. A serine protease physiologically often comes together with a cognate inhibitor for execution of proteolytically biologic function; however, TMPRSS2's cognate inhibitor is still elusive. To identify the cognate inhibitor of TMPRSS2, in this study, we applied co-immunoprecipitation and LC/MS/MS analysis and isolated hepatocyte growth factor activator inhibitors (HAIs) to be potential inhibitor candidates for TMPRSS2. Moreover, the recombinant HAI-2 proteins exhibited a better inhibitory effect on TMPRSS2 proteolytic activity than HAI-1, and recombinant HAI-2 proteins had a high affinity to form a complex with TMPRSS2. The immunofluorescence images further showed that TMPRSS2 was co-localized to HAI-2. Both KD1 and KD2 domain of HAI-2 showed comparable inhibitory effects on TMPRSS2 proteolytic activity. In addition, HAI-2 overexpression could suppress the induction effect of TMPRSS2 on pro-HGF activation, extracellular matrix degradation and prostate cancer cell invasion. We further determined that the expression levels of TMPRSS2 were inversely correlated with HAI-2 levels during prostate cancer progression. In orthotopic xenograft animal model, TMPRSS2 overexpression promoted prostate cancer metastasis, and HAI-2 overexpression efficiently blocked TMPRSS2-induced metastasis. In summary, the results together indicate that HAI-2 can function as a cognate inhibitor for TMPRSS2 in human prostate cancer cells and may serve as a potential factor to suppress TMPRSS2-mediated malignancy.


Assuntos
Glicoproteínas de Membrana/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Serina Endopeptidases/metabolismo , Animais , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Xenoenxertos , Humanos , Masculino , Glicoproteínas de Membrana/química , Invasividade Neoplásica , Neoplasias da Próstata/etiologia , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Proteólise
10.
Am J Otolaryngol ; 40(1): 22-29, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30249374

RESUMO

PURPOSE: The efficacy of postoperative oral corticosteroids on surgical outcomes in chronic rhinosinusitis with nasal polyps (CRSwNP) patients following endoscopic sinus surgery (ESS) remains controversial. This study evaluated the potential benefits of postoperative oral corticosteroids on surgical outcomes in CRSwNP patients and investigated the differential effects on eosinophilic CRSwNP (ECRSwNP) and noneosinophilic CRSwNP (NECRSwNP). MATERIALS AND METHODS: Patients with bilateral CRSwNP who underwent ESS were enrolled and randomized to receive either oral prednisolone (30 mg/day) or placebo for 2 weeks after surgery. Visual analog scale (VAS) and Sino-Nasal Outcome Test 22 (SNOT-22) scores were chosen as the subjective outcomes, evaluated at preoperative baseline and 1, 3, and 6 months postoperatively. Lund-Kennedy Endoscopic Scores (LKESs) were used as the objective outcome, evaluated at preoperative baseline and at 2 weeks and 2, 3, and 6 months postoperatively. RESULTS: In total, 100 patients with bilateral CRSwNP were enrolled, of whom only 82 completed the 6-month follow-up. The subjective outcomes showed no significant difference at each follow-up points. Of the objective outcomes, the corticosteroid group reporting a trend of improvement in LKESs at 6 months postoperatively (p = 0.05). After stratification by tissue eosinophils, only patients with NECRSwNP (<10 eosinophils/HPF) demonstrated a significant improvement in LKESs at 3 months postoperatively (p = 0.03). CONCLUSIONS: Postoperative oral corticosteroids did not provide additional improvements in VAS and SNOT-22 scores; nevertheless, a trend of LKES improvement was noted at 6 months postoperatively. After stratification by tissue eosinophils, this effect was significant only among NECRSwNP patients at 3 months follow-up.


Assuntos
Eosinofilia/terapia , Glucocorticoides/administração & dosagem , Pólipos Nasais/terapia , Prednisolona/administração & dosagem , Rinite/terapia , Sinusite/terapia , Administração Oral , Adulto , Doença Crônica , Endoscopia , Eosinofilia/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/etiologia , Cuidados Pós-Operatórios , Rinite/etiologia , Sinusite/etiologia , Resultado do Tratamento
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