Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.344
Filtrar
1.
Biochem Biophys Res Commun ; 608: 52-58, 2022 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-35390672

RESUMO

Sialylation, the final stage of post-translational modification of proteins, is achieved in the Golgi apparatus and is related to the malignant phenotype of cancer. Disialylation of ganglioside (GD3) by St8sia1 and polysialylation by St8sia2 and 4 have been shown to be related to malignant phenotypes; however, di/oligosialylation by St8sia6 is still unknown. In this study, we analyzed the malignant phenotype of St8sia6 and found that upregulation of St8sia6 in melanoma B16 cells increased anchorage-independent cell growth, which was not due to sialic acid cleavage by a sialidase. Moreover, unlike other sialyltransferases, St8sia6 localized to the endoplasmic reticulum (ER). We found that the localization to the Golgi apparatus could be regulated by swapping experiments using St8sia2; however, the malignant phenotype did not change. These data demonstrate that the enhancement of anchorage-independent cell growth by St8sia6 is not due to its localization of ER, but is due to the expression of the protein itself.


Assuntos
Retículo Endoplasmático , Neoplasias , Sialiltransferases , Processos de Crescimento Celular , Retículo Endoplasmático/enzimologia , Retículo Endoplasmático/metabolismo , Gangliosídeos/metabolismo , Complexo de Golgi/metabolismo , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Sialiltransferases/metabolismo
2.
Aging (Albany NY) ; 14(3): 1068-1086, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35158337

RESUMO

Radiation therapy is a commonly used treatment modality for cancer. Although effective in providing local tumor control, radiation causes oxidative stress, inflammation, immunomodulatory and mitogenic cytokine production, extracellular matrix production, and premature senescence in lung parenchyma. The senescence associated secretory phenotype (SASP) can promote inflammation and stimulate alterations in the surrounding tissue. Therefore, we hypothesized that radiation-induced senescent parenchymal cells in irradiated lung would enhance tumor growth. Using a murine syngeneic tumor model of melanoma and non-small cell lung cancer lung metastasis, we demonstrate that radiation causes a significant increase in markers of premature senescence in lung parenchyma within 4 to 8 weeks. Further, injection of B16F0 (melanoma) or Lewis Lung carcinoma (epidermoid lung cancer) cells at these time points after radiation results in an increase in the number and size of pulmonary tumor nodules relative to unirradiated mice. Treatment of irradiated mice with a senolytic agent (ABT-737) or agents that prevent senescence (rapamycin, INK-128) was sufficient to reduce radiation-induced lung parenchymal senescence and to mitigate radiation-enhanced tumor growth. These agents abrogated radiation-induced expression of 12-Lipoxygenase (12-LOX), a molecule implicated in several deleterious effects of senescence. Deficiency of 12-LOX prevented radiation-enhanced tumor growth. Together, these data demonstrate the pro-tumorigenic role of radiation-induced senescence, introduces the dual TORC inhibitor INK-128 as an effective agent for prevention of radiation-induced normal tissue senescence, and identifies senescence-associated 12-LOX activity as an important component of the pro-tumorigenic irradiated tissue microenvironment. These studies suggest that combining senotherapeutic agents with radiotherapy may decrease post-therapy tumor growth.


Assuntos
Carcinoma Pulmonar de Lewis , Neoplasias Pulmonares , Melanoma Experimental , Animais , Araquidonato 12-Lipoxigenase/farmacologia , Carcinoma Pulmonar de Lewis/enzimologia , Carcinoma Pulmonar de Lewis/patologia , Processos de Crescimento Celular , Senescência Celular , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Melanoma Experimental/enzimologia , Melanoma Experimental/patologia , Camundongos , Microambiente Tumoral
3.
Cancer Control ; 29: 10732748211068963, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35043700

RESUMO

The possible role of the naturally occurring deuterium in the regulation of cell division was first described in the 1990s. To investigate the mechanism of influence of deuterium (D) on cell growth, expression of 236 cancer-related and 536 kinase genes were tested in deuterium-depleted (40 and 80 ppm) and deuterium-enriched (300 ppm) media compared to natural D level (150 ppm). Among genes with expression changes exceeding 30% and copy numbers over 30 (124 and 135 genes, respectively) 97.3% of them was upregulated at 300 ppm D-concentration. In mice exposed to chemical carcinogen, one-year survival data showed that deuterium-depleted water (DDW) with 30 ppm D as drinking water prevented tumor development. One quarter of the treated male mice survived 344 days, the females 334 days, while one quarter of the control mice survived only 188 and 156 days, respectively. In our human retrospective study 204 previously treated cancer patients with disease in remission, who consumed DDW, were followed. Cumulative follow-up time was 1024 years, and average follow-up time per patient, 5 years (median: 3.6 years). One hundred and fifty-six patients out of 204 (77.9%) did not relapse during their 803 years cumulative follow-up time. Median survival time (MST) was not calculable due to the extremely low death rate (11 cancer-related deaths, 5.4% of the study population). Importantly, 8 out of 11 deaths occurred several years after stopping DDW consumption, confirming that regular consumption of DDW can prevent recurrence of cancer. These findings point to the likely mechanism in which consumption of DDW keeps D-concentration below natural levels, preventing the D/H ratio from increasing to the threshold required for cell division. This in turn can serve as a key to reduce the relapse rate of cancer patients and/or to reduce cancer incidence in healthy populations.


Assuntos
Deutério/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Recidiva Local de Neoplasia/genética , Neoplasias/genética , Água/administração & dosagem , Animais , Processos de Crescimento Celular/efeitos dos fármacos , Variações do Número de Cópias de DNA/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Recidiva Local de Neoplasia/prevenção & controle , Estudos Retrospectivos , Água/química
4.
BMC Cancer ; 22(1): 105, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35078427

RESUMO

BACKGROUND: Nutrient acquisition and metabolism pathways are altered in cancer cells to meet bioenergetic and biosynthetic demands. A major regulator of cellular metabolism and energy homeostasis, in normal and cancer cells, is AMP-activated protein kinase (AMPK). AMPK influences cell growth via its modulation of the mechanistic target of Rapamycin (mTOR) pathway, specifically, by inhibiting mTOR complex mTORC1, which facilitates cell proliferation, and by activating mTORC2 and cell survival. Given its conflicting roles, the effects of AMPK activation in cancer can be counter intuitive. Prior to the establishment of cancer, AMPK acts as a tumor suppressor. However, following the onset of cancer, AMPK has been shown to either suppress or promote cancer, depending on cell type or state. METHODS: To unravel the controversial roles of AMPK in cancer, we developed a computational model to simulate the effects of pharmacological maneuvers that target key metabolic signalling nodes, with a specific focus on AMPK, mTORC, and their modulators. Specifically, we constructed an ordinary differential equation-based mechanistic model of AMPK-mTORC signaling, and parametrized the model based on existing experimental data. RESULTS: Model simulations were conducted to yield the following predictions: (i) increasing AMPK activity has opposite effects on mTORC depending on the nutrient availability; (ii) indirect inhibition of AMPK activity through inhibition of sirtuin 1 (SIRT1) only has an effect on mTORC activity under conditions of low nutrient availability; (iii) the balance between cell proliferation and survival exhibits an intricate dependence on DEP domain-containing mTOR-interacting protein (DEPTOR) abundance and AMPK activity; (iv) simultaneous direct inhibition of mTORC2 and activation of AMPK is a potential strategy for suppressing both cell survival and proliferation. CONCLUSIONS: Taken together, model simulations clarify the competing effects and the roles of key metabolic signalling pathways in tumorigenesis, which may yield insights on innovative therapeutic strategies.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Carcinogênese/metabolismo , Neoplasias/enzimologia , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Processos de Crescimento Celular , Proliferação de Células , Simulação por Computador , Metabolismo Energético , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
5.
BMC Cancer ; 22(1): 100, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35073851

RESUMO

BACKGROUND: Platinum chemoresistance results in high-grade serous ovarian cancer (HGSOC) disease recurrence. Recent treatment advances using checkpoint inhibitor immunotherapy has not benefited platinum-resistant HGSOC. In ovarian cancer, DNA methyltransferase inhibitors (DNMTi) block methylation and allow expression of silenced genes, primarily affecting immune reactivation pathways. We aimed to determine the epigenome and transcriptome response to sequential treatment with DNMTi and carboplatin in HGSOC. METHODS: In vitro studies with azacitidine or carboplatin alone and in sequential combination. Response was determined by cell growth, death and apoptosis. Genome-wide DNA methylation levels and transcript expression were compared between untreated and azacitidine and carboplatin sequential treatment. RESULTS: Sequential azacitidine and carboplatin significantly slowed cell growth in 50% of cell lines compared to carboplatin alone. The combination resulted in significantly higher cell death in 25% of cell lines, and significantly higher cell apoptosis in 37.5% of cell lines, than carboplatin alone. Pathway analysis of upregulated transcripts showed that the majority of changes were in immune-related pathways, including those regulating response to checkpoint inhibitors. CONCLUSIONS: Sequential azacitidine and carboplatin treatment slows cell growth, and demethylate and upregulate pathways involved in immune response, suggesting that this combination may be used to increase HGSOC response to immune checkpoint inhibitors in platinum-resistant patients who have exhausted all currently-approved avenues of treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Azacitidina/administração & dosagem , Carboplatina/administração & dosagem , Imunidade/efeitos dos fármacos , Neoplasias Císticas, Mucinosas e Serosas/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/imunologia , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/imunologia , Feminino , Humanos , Inibidores de Checkpoint Imunológico/administração & dosagem , Gradação de Tumores , Neoplasias Císticas, Mucinosas e Serosas/imunologia , Neoplasias Ovarianas/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/imunologia
6.
Explore (NY) ; 18(2): 205-209, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33341371

RESUMO

OBJECTIVE: Mitochondria are considered a portal to receive, process and integrate external energy and information to maintain cellular homeostasis. We examined the effect of Chinese texts with positive and negative meaning on the growth and mitochondrial functions using a mouse kidney collecting duct cell line called M1 cells. METHODS: To avoid skewing the results due to differential handling of the cells or analyzing the results, we conducted experiments by keeping the texts and blanks covered in brown opaque envelopes, exposed the cells to randomly selected envelopes and examined the differences over time. All operators involved in the experiments did not know the contents of the envelopes until the end of the experiments, and all data are expressed relative to the controls. RESULTS: Cell growth rate was not affected for the group treated with positive information but was significantly reduced by 18% when treated with negative information. At the biochemical level, positive texts significantly increased whole cell adenosine triphosphate (ATP) and glutathione (GSH) by 22% and 21% respectively. CONCLUSIONS: This study for the first time demonstrated the effect of written words on specific biochemical measures in cultured mammalian cells.


Assuntos
Atitude , Viés , Processos de Crescimento Celular , Mitocôndrias , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/metabolismo , Animais , Pesquisa Biomédica , Processos de Crescimento Celular/fisiologia , Linhagem Celular , Glutationa/análise , Glutationa/metabolismo , Humanos , Camundongos , Mitocôndrias/metabolismo , Redação
7.
Immunol Lett ; 241: 35-48, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34890699

RESUMO

Cancer is known to have systemic impact by targeting various organs that ultimately compromises the overall physiology of the host. Several reports have demonstrated the role of neutrophils in cancer wherein the focus has been drawn on the elevated neutrophil count in blood or at tumor loci. However, their role in mediating systemic effects during cancer progression has not been deciphered so far. Therefore, it is worthwhile to explore whether and how neutrophils contribute to systemic deterioration in cancer. To discern their systemic role, we evaluated neutrophil count and function at different stages of tumor growth in Dalton's Lymphoma mice model. Notably, our results displayed a gradual increase in Ly6G+ neutrophils in peripheral blood and their infiltration in vital organs including liver, lungs, spleen, kidney, lymph nodes and peritoneum of tumor bearing host. We showed remarkable alterations in histoarchitecture and serum enzyme levels that aggravated with tumor progression. We next examined neutrophil function by assessing its granular cargoes including neutrophil elastase (NE), myeloperoxidase (MPO), and matrix metalloproteinases (MMP-8 and MMP-9). Interestingly, blood neutrophils of tumor bearing mice exhibited a marked change in morphology with gradual increase in NE and MPO expression with tumor growth. In addition, we observed upregulated expression of NE, MPO, MMP-8 and MMP-9 in the vital organs of tumor bearing host. Taken together, our results demonstrate heightened infiltration and function of neutrophils in vital organs of tumor bearing host which possibly account for gradual systemic deterioration during cancer progression. Our findings thus implicate neutrophils as a potential therapeutic target that may help to reduce the overall fatality rate of cancer.


Assuntos
Elastase de Leucócito/metabolismo , Linfoma/imunologia , Metaloproteinase 9 da Matriz/metabolismo , Neutrófilos/fisiologia , Peroxidase/metabolismo , Animais , Processos de Crescimento Celular , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais , Ativação de Neutrófilo
8.
J Invest Dermatol ; 142(1): 179-188.e4, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34224745

RESUMO

The hedgehog (Hh) pathway is essential for animal development, but aberrant activation promotes cancer growth. In this study, we show that GIPC3, a PDZ domain-containing protein with putative adaptor protein function, positively modulates Hh target gene expression in normal fibroblasts and melanoma cells and supports melanoma tumor growth. Using overexpression and epistasis studies, we show that Gipc3 potentiates Hh transcriptional output and that it modulates GLI-dependent transcription independently of Sufu. Whereas we find that GIPC3 protein does not interact with Hh pathway components, Ingenuity Pathway Analyses of GIPC3-interacting proteins identified by coimmunoprecipitation and mass spectrometry show an association with cancer pathogenesis. Subsequent interrogation of The Cancer Genome Atlas and the Human Protein Atlas databases reveals GIPC3 upregulation in many cancers. Using expression screens in selected groups of GIPC3-upregulated cancers with reported Hh pathway activation, we find a significant positive correlation of GIPC3 expression with Hh pathway components GLI1, GLI2, and GPR161 in melanoma lines. Consistently, GIPC3 knockdown in melanoma lines significantly reduces GLI1 and GLI2 expression, cell viability, colony formation, and allograft tumor growth. Our findings highlight previously unidentified roles of GIPC3 in potentiating Hh response and melanoma tumorigenesis and suggest that GIPC3 modulation on Hh signaling may be targeted to reduce melanoma growth.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Aloenxertos , Animais , Carcinogênese , Processos de Crescimento Celular , Regulação Neoplásica da Expressão Gênica , Ouriços-Cacheiros/metabolismo , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Proteína GLI1 em Dedos de Zinco/genética , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína Gli2 com Dedos de Zinco/genética , Proteína Gli2 com Dedos de Zinco/metabolismo
9.
Asian Pac J Cancer Prev ; 22(11): 3607-3613, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837919

RESUMO

BACKGROUND: Glioblastoma Multiforme (GBM) is a deadly tumor with poor prognosis. Resistance to apoptosis considered as an important factor in treatment failure. Therefore, identification of new compounds that facilitates apoptosis is crucial. Natural Anti-inflammatory compounds have emerged as potential anti-cancer agents and should be explored for their apoptotic activity against GBM. Therefore, the present study aims to evaluate growth inhibitory and apoptotic activity of a natural anti-inflammatory compound "Opuntiol" against GBM cell line U87. METHODS: MTT assay was performed to determine the effect of Temozolomide and Opuntiol on growth inhibition of U87 cell. While, TUNEL assay was used to assess their apoptotic activity. To further assess apoptosis, nuclear condensation and nuclear area factor (NAF) was evaluated through DAPI staining. Whereas, active caspase-3 protein expression determined using immunocytochemistry. RESULTS: Significant growth inhibition was observed in U87 cells treated with Temozolomide (IC50 380 µM) and Opuntiol (IC50 357 µM). Temozolomide (p<0.001) and Opuntiol (p<0.001) significantly improved rate of apoptosis when compared to control group. A significant decrease in NAF was also observed in Temozolomide (p < 0.05) and Opuntiol (p < 0.05) treated cells. There was a significant increase in active caspase-3 expression when observed in Temozolomide (p<0.001) and Opuntiol (p<0.05) treated groups as compared to control. CONCLUSION: In conclusion our findings suggests, Opuntiol repress cell viability and possess strong apoptotic activity against GBM cell line U-87. However, further mechanistic studies will be required to confirm whether it can be develop as a potential drug against GBM.


Assuntos
Antineoplásicos/farmacologia , Caspase 3/efeitos dos fármacos , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Ácidos Cumáricos/farmacologia , Glioblastoma/tratamento farmacológico , Apoptose/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Sistema Nervoso Central/enzimologia , Glioblastoma/enzimologia , Humanos , Temozolomida/farmacologia , Regulação para Cima/efeitos dos fármacos
10.
Asian Pac J Cancer Prev ; 22(11): 3633-3640, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837922

RESUMO

OBJECTIVE: The study aimed to investigate the inhibitory effects of AL on the ERK signaling molecules (ERK, p-ERK, cyclin D, and eIF4B) and the growth and proliferation of CCA cells. MATERIALS AND METHODS: The viability of the three CCA cell lines CL-6, HuCCT1, and HuH28 was determined using MTT assay. The effect of Ras/ERK inhibitors on protein expression in the presence of AL extract was investigated. The protein extracted from each CCA cell following exposure to AL and/or Ras/ERK inhibitors were separated on 12.5% SDS-PAGE. The analysis of mRNA expression following 48 and 72 hours of AL exposure in comparison with 0 hours (non-exposed cells) was performed by using RT-PCR. RESULTS: The potency of cytotoxic activity of AL (by MTT assay) was about three times higher than the standard drug 5-fluorouracil. The IC50 (concentration that inhibits cell growth by 50%) of AL for the CL-6, HuCCT-1 and HuH28 cell lines were 29.77±6.64, 35.45±4.96, and 35.32±6.69 µg/mL (mean+SD), respectively. The cells were exposed to AL extract at the IC50 for 0, 12, 24, 48, and 72 hours in the absence and presence of Ras/ERK inhibitors (salirasib and XMD8-92). Protein expression was determined by Western blot analysis. The results suggested the lack of significant inhibitory effect of AL on ERK at 48 and 72 hours of exposure in all CCA cell types. On the other hand, a significant inhibitory effect was observed with p-ERK expression in all CCA cell types. Cyclin D was significantly down-regulated at 72 hours of exposure in all cell types with different potencies. The expression of eIF4B was markedly inhibited in HuCCT-1 but slightly inhibited in CL-6 and HuH28 cells. Real-time PCR analysis revealed significant down-regulation of ERK following 72 hours of AL exposure in the HuCCT1 and HuH28, but not CL-6 cell. CONCLUSION: The ERK signaling cascade and downstream molecules are potential targets of action of AL in CCA.


Assuntos
Antineoplásicos/farmacologia , Atractylodes , Neoplasias dos Ductos Biliares/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Extratos Vegetais/farmacologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Fluoruracila/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos
11.
Immunity ; 54(12): 2724-2739.e10, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34687607

RESUMO

Nitric oxide (NO) is an important antimicrobial effector but also prevents unnecessary tissue damage by shutting down the recruitment of monocyte-derived phagocytes. Intracellular pathogens such as Leishmania major can hijack these cells as a niche for replication. Thus, NO might exert containment by restricting the availability of the cellular niche required for efficient pathogen proliferation. However, such indirect modes of action remain to be established. By combining mathematical modeling with intravital 2-photon biosensors of pathogen viability and proliferation, we show that low L. major proliferation results not from direct NO impact on the pathogen but from reduced availability of proliferation-permissive host cells. Although inhibiting NO production increases recruitment of these cells, and thus pathogen proliferation, blocking cell recruitment uncouples the NO effect from pathogen proliferation. Therefore, NO fulfills two distinct functions for L. major containment: permitting direct killing and restricting the supply of proliferation-permissive host cells.


Assuntos
Leishmania major/fisiologia , Leishmaniose/imunologia , Macrófagos/imunologia , Óxido Nítrico/metabolismo , Animais , Processos de Crescimento Celular , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Interações Hospedeiro-Patógeno , Humanos , Microscopia Intravital , Camundongos , Camundongos Endogâmicos C57BL , Modelos Teóricos
12.
J Immunol ; 207(8): 2107-2117, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526375

RESUMO

A multifunctional glycoprotein, osteopontin (OPN), can modulate the function of macrophages, resulting in either protective or deleterious effects in various inflammatory diseases and infection in the lungs. Although macrophages play the critical roles in mediating host defenses against cryptococcosis or cryptococcal pathogenesis, the involvement of macrophage-derived OPN in pulmonary infection caused by fungus Cryptococcus has not been elucidated. Thus, our current study aimed to investigate the contribution of OPN to the regulation of host immune response and macrophage function using a mouse model of pulmonary cryptococcosis. We found that OPN was predominantly expressed in alveolar macrophages during C. neoformans infection. Systemic treatment of OPN during C. neoformans infection resulted in an enhanced pulmonary fungal load and an early onset of type 2 inflammation within the lung, as indicated by the increase of pulmonary eosinophil infiltration, type 2 cytokine production, and M2-associated gene expression. Moreover, CRISPR/Cas9-mediated OPN knockout murine macrophages had enhanced ability to clear the intracellular fungus and altered macrophage phenotype from pathogenic M2 to protective M1. Altogether, our data suggested that macrophage-derived OPN contributes to the elaboration of C. neoformans-induced type 2 immune responses and polarization of M2s that promote fungal survival and proliferation within macrophages.


Assuntos
Criptococose/imunologia , Cryptococcus neoformans/fisiologia , Eosinófilos/imunologia , Pulmão/patologia , Macrófagos/imunologia , Osteopontina/metabolismo , Células Th2/imunologia , Animais , Diferenciação Celular , Processos de Crescimento Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Humanos , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Osteopontina/genética , Equilíbrio Th1-Th2
13.
Oncogene ; 40(41): 6007-6022, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34400766

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has an extremely poor prognosis, and is plagued by a paucity of targeted treatment options and tumour resistance to chemotherapeutics. The causal link between chronic inflammation and PDAC suggests that molecular regulators of the immune system promote disease pathogenesis and/or therapeutic resistance, yet their identity is unclear. Here, we couple endoscopic ultrasound-guided fine-needle aspiration, which captures tumour biopsies from all stages, with whole transcriptome profiling of PDAC patient primary tumours to reveal enrichment of the innate immune Toll-like receptor 2 (TLR2) molecular pathway. Augmented TLR2 expression associated with a 4-gene "TLR2 activation" signature, and was prognostic for survival and predictive for gemcitabine-based chemoresistance. Furthermore, antibody-mediated anti-TLR2 therapy suppressed the growth of human PDAC tumour xenografts, independent of a functional immune system. Our results support TLR2-based therapeutic targeting for precision medicine in PDAC, with further clinical utility that TLR2 activation is prognostic and predictive for chemoresponsiveness.


Assuntos
Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Receptor 2 Toll-Like/metabolismo , Animais , Carcinoma Ductal Pancreático/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Desoxicitidina/farmacologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Terapia de Alvo Molecular , Neoplasias Pancreáticas/patologia , Prognóstico , Análise de Sobrevida , Receptor 2 Toll-Like/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
14.
FASEB J ; 35(9): e21742, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34403506

RESUMO

Withdrawal from contact inhibition is necessary for epithelial cancer precursor cells to initiate cell growth and motility. Nevertheless, little is understood about the mechanism for the sudden initiation of cell growth under static conditions. We focused on cellular junctions as one region where breaking out of contact inhibition occurs. In well-differentiated endometrial cancer cells, Sawano, the ligand administration for tricellular tight junction protein LSR, which transiently decreased the robust junction property, caused an abrupt increase in cell motility and consequent excessive multilayered cell growth despite being under contact inhibition conditions. We observed that macropinocytosis essentially and temporarily occurred as an antecedent event for the above process at intercellular junctions without disruption of the junction apparatus but not at the apical plasma membrane. Collectively, we concluded that the formation of macropinocytosis, which is derived from tight junction-mediated signaling, was triggered for the initiation of cell growth in static precancerous epithelium.


Assuntos
Adesão Celular , Inibição de Contato , Pinocitose , Receptores de Lipoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Toxinas Bacterianas/farmacologia , Sítios de Ligação , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Junções Intercelulares/efeitos dos fármacos , Junções Intercelulares/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fenótipo , Pinocitose/efeitos dos fármacos , Transporte Proteico , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo , Proteínas rac de Ligação ao GTP/metabolismo
16.
FEBS Lett ; 595(18): 2383-2394, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34358326

RESUMO

Maintenance of the proteome (proteostasis) is essential for cellular homeostasis and prevents cytotoxic stress responses that arise from protein misfolding. However, little is known about how different types of misfolded proteins impact homeostasis, especially when protein degradation pathways are compromised. We examined the effects of misfolded protein expression on yeast growth by characterizing a suite of substrates possessing the same aggregation-prone domain but engaging different quality control pathways. We discovered that treatment with a proteasome inhibitor was more toxic in yeast expressing misfolded membrane proteins, and this growth defect was mirrored in yeast lacking a proteasome-specific transcription factor, Rpn4p. These results highlight weaknesses in the proteostasis network's ability to handle the stress arising from an accumulation of misfolded membrane proteins.


Assuntos
Complexo de Endopeptidases do Proteassoma/metabolismo , Dobramento de Proteína , Proteínas de Saccharomyces cerevisiae/classificação , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Processos de Crescimento Celular/efeitos dos fármacos , Citoplasma/metabolismo , Proteínas de Ligação a DNA/deficiência , Degradação Associada com o Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Nucleotídeos/metabolismo , Inibidores de Proteassoma/farmacologia , Ligação Proteica , Domínios Proteicos , Proteólise , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/química , Fatores de Transcrição/deficiência
17.
Sci Rep ; 11(1): 14827, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290272

RESUMO

Inactivation of the tumor suppressor von Hippel-Lindau (VHL) gene is a key event in hereditary and sporadic clear cell renal cell carcinomas (ccRCC). The mechanistic target of rapamycin (mTOR) signaling pathway is a fundamental regulator of cell growth and proliferation, and hyperactivation of mTOR signaling is a common finding in VHL-dependent ccRCC. Deregulation of mTOR signaling correlates with tumor progression and poor outcome in patients with ccRCC. Here, we report that the regulatory-associated protein of mTOR (RAPTOR) is strikingly repressed by VHL. VHL interacts with RAPTOR and increases RAPTOR degradation by ubiquitination, thereby inhibiting mTORC1 signaling. Consistent with hyperactivation of mTORC1 signaling in VHL-deficient ccRCC, we observed that loss of vhl-1 function in C. elegans increased mTORC1 activity, supporting an evolutionary conserved mechanism. Our work reveals important new mechanistic insight into deregulation of mTORC1 signaling in ccRCC and links VHL directly to the control of RAPTOR/mTORC1. This may represent a novel mechanism whereby loss of VHL affects organ integrity and tumor behavior.


Assuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteína Regulatória Associada a mTOR/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteína Supressora de Tumor Von Hippel-Lindau/fisiologia , Animais , Caenorhabditis elegans , Carcinoma de Células Renais/patologia , Processos de Crescimento Celular/genética , Proliferação de Células/genética , Células HEK293 , Humanos , Neoplasias Renais/patologia , Ubiquitinação/genética
18.
PLoS Genet ; 17(7): e1009678, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34260587

RESUMO

Animals can adapt to dynamic environmental conditions by modulating their developmental programs. Understanding the genetic architecture and molecular mechanisms underlying developmental plasticity in response to changing environments is an important and emerging area of research. Here, we show a novel role of cAMP response element binding protein (CREB)-encoding crh-1 gene in developmental polyphenism of C. elegans. Under conditions that promote normal development in wild-type animals, crh-1 mutants inappropriately form transient pre-dauer (L2d) larvae and express the L2d marker gene. L2d formation in crh-1 mutants is specifically induced by the ascaroside pheromone ascr#5 (asc-ωC3; C3), and crh-1 functions autonomously in the ascr#5-sensing ASI neurons to inhibit L2d formation. Moreover, we find that CRH-1 directly binds upstream of the daf-7 TGF-ß locus and promotes its expression in the ASI neurons. Taken together, these results provide new insight into how animals alter their developmental programs in response to environmental changes.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adaptação Fisiológica/genética , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Ciclo Celular , Processos de Crescimento Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Larva/genética , Larva/crescimento & desenvolvimento , Feromônios/metabolismo , Células Receptoras Sensoriais/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/fisiologia
19.
Nat Commun ; 12(1): 3819, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155210

RESUMO

Active coacervate droplets are liquid condensates coupled to a chemical reaction that turns over their components, keeping the droplets out of equilibrium. This turnover can be used to drive active processes such as growth, and provide an insight into the chemical requirements underlying (proto)cellular behaviour. Moreover, controlled growth is a key requirement to achieve population fitness and survival. Here we present a minimal, nucleotide-based coacervate model for active droplets, and report three key findings that make these droplets into evolvable protocells. First, we show that coacervate droplets form and grow by the fuel-driven synthesis of new coacervate material. Second, we find that these droplets do not undergo Ostwald ripening, which we attribute to the attractive electrostatic interactions and translational entropy within complex coacervates, active or passive. Finally, we show that the droplet growth rate reflects experimental conditions such as substrate, enzyme and protein concentration, and that a different droplet composition (addition of RNA) leads to altered growth rates and droplet fitness. These findings together make active coacervate droplets a powerful platform to mimic cellular growth at a single-droplet level, and to study fitness at a population level.


Assuntos
Células Artificiais/química , Células Artificiais/citologia , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Processos de Crescimento Celular , Elastina/química , Peptídeos/química , Fosfoenolpiruvato/metabolismo , Piruvato Quinase/metabolismo
20.
Nucleic Acids Res ; 49(12): 7011-7034, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34125917

RESUMO

The modification of adenosine to inosine at the wobble position (I34) of tRNA anticodons is an abundant and essential feature of eukaryotic tRNAs. The expansion of inosine-containing tRNAs in eukaryotes followed the transformation of the homodimeric bacterial enzyme TadA, which generates I34 in tRNAArg and tRNALeu, into the heterodimeric eukaryotic enzyme ADAT, which modifies up to eight different tRNAs. The emergence of ADAT and its larger set of substrates, strongly influenced the tRNA composition and codon usage of eukaryotic genomes. However, the selective advantages that drove the expansion of I34-tRNAs remain unknown. Here we investigate the functional relevance of I34-tRNAs in human cells and show that a full complement of these tRNAs is necessary for the translation of low-complexity protein domains enriched in amino acids cognate for I34-tRNAs. The coding sequences for these domains require codons translated by I34-tRNAs, in detriment of synonymous codons that use other tRNAs. I34-tRNA-dependent low-complexity proteins are enriched in functional categories related to cell adhesion, and depletion in I34-tRNAs leads to cellular phenotypes consistent with these roles. We show that the distribution of these low-complexity proteins mirrors the distribution of I34-tRNAs in the phylogenetic tree.


Assuntos
Inosina/metabolismo , Biossíntese de Proteínas , RNA de Transferência/metabolismo , Adenosina Desaminase/genética , Adesão Celular , Processos de Crescimento Celular , Linhagem Celular , Códon , Eucariotos/genética , Feminino , Células HEK293 , Humanos , Domínios Proteicos/genética , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/metabolismo , RNA de Transferência/química , Ribossomos/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...