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Following the publication of the above article, a concerned reader drew to the Editor's attention that there were a number of apparent anomalies associated with the western blots featured in Figs. 1C and E, 3A, C and E, 4A, C and E, 5B, 8A and C; moreover, the images shown for the immunohistochemical experiments in Fig. 8E contained groupings of cells that were markedly similar in appearance, comparing across the eight separate figure parts. After having conducted an internal investigation of the data in this paper, the Editor of International Journal of Molecular Medicine has judged that the potentially anomalous presentation of the western blotting data and the strikingly similar groupings of cells in Fig. 8E were too extensive that these features could have been attributed to pure coincidence. Therefore, the Editor has decided that this article should be retracted from the publication on the grounds of an overall lack of confidence in the data. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor sincerely apologizes to the readership for any incovenience caused, and we thank the reader for bringing this matter to our attention. [International Journal of Molecular Medicine 35: 653663, 2015; DOI: 10.3892/ijmm.2014.2055].
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Tuft cells are solitary chemosensory cells distributed mainly in hollow organs and detected in human and mouse pancreas precursor lesions of pancreatic cancer. Induced by inflammation and KRAS mutation, pancreatic acinar cell-derived tuft cells play a protective role in epithelium injury. The tumour suppression of tuft cells has been indicated in some studies. However, the function of tuft cells in pancreatic cancer remains unclear. In this review, we first introduce the definition of tuft cells and then review the relationship between tuft cells and pancreatic inflammation. In addition, we emphasized the role of tuft cells in the genesis and development of pancreatic cancers, especially the part of markers for tuft cell's doublecortin-like kinase 1 (DCLK1). Finally, we turn to the microscopic perspective and review the interactions between tuft cells and the microbiome in the pancreatic microenvironment. Overall, we describe the role of tuft cells in response to tissue damage and tumour progression in the pancreas. Nevertheless, the specific formation principle and the more detailed mechanism of action of tuft cells in the pancreas remain to be further explored.
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Pâncreas , Neoplasias Pancreáticas , Camundongos , Animais , Humanos , Pâncreas/patologia , Proteínas Serina-Treonina Quinases/genética , Neoplasias Pancreáticas/patologia , Inflamação/patologia , Microambiente Tumoral , Quinases Semelhantes a Duplacortina , Neoplasias PancreáticasRESUMO
Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer related death. A growing number of studies believe that matrix stiffness plays an important role in the development of pancreatic disease. As one of the famous mechanically activated cation channels, Piezo1 has received more attention recently. Here we tried to describe the role of Piezo1 on PDAC progression. It seemed that Piezo1 was a potential tumor-promoting marker of pancreatic cancer. By using Yoda1, we measured the intracellular calcium flux mediated by Piezo1 which confirmed it did act as an intrinsic cation channel in pancreatic cancer cells. Additionally, we also found the inhibition of Piezo1 could inhibit cancer progression in vitro; however, Piezo1 activation (induced by Yoda1) had an oppositive effect. Moreover, Piezo1 activation may also accelerate pancreatic cancer tumor growth/formation via modulating pancreatic cancer cell-tumor microenvironment interactions in vivo. We concluded that Piezo1 acted as an oncogenic gene in pancreatic cancer progression. It might be one of promising targets for pancreatic cancer therapy.
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Canais Iônicos , Neoplasias Pancreáticas , Humanos , Mecanotransdução Celular/fisiologia , Pâncreas/metabolismo , Hormônios Pancreáticos , Oncogenes/genética , Neoplasias Pancreáticas/genética , Microambiente TumoralRESUMO
As one of the best-studied long noncoding RNAs, nuclear paraspeckle assembly transcript 1 (NEAT1) plays a pivotal role in the progression of cancers. NEAT1, especially its isoform NEAT1-1, facilitates the growth and metastasis of various cancers, excluding acute promyelocytic leukemia. NEAT1 can be elevated via transcriptional activation or stability alteration in cancers changing the aggressive phenotype of cancer cells. NEAT1 can also be secreted from other cells and be delivered to cancer cells through exosomes. Hence, elucidating the molecular interaction of NEAT1 may shed light on the future treatment of cancer. Herein, we review the molecular function of NEAT1 in cancer progression, and explain how NEAT1 interacts with RNAs, proteins, and DNA promoter regions to upregulate tumorigenic factors.
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Perineural invasion (PNI) is a pathologic feature of pancreatic cancer and is associated with poor outcomes, metastasis, and recurrence in pancreatic cancer patients. However, the molecular mechanism of PNI remains unclear. The present study aimed to investigate the mechanism that HGF/c-Met pathway facilitates the PNI of pancreatic cancer. In this study, we confirmed that c-Met expression was correlated with PNI in pancreatic cancer tissues. Activating the HGF/c-Met signaling pathway potentiated the expression of nerve growth factor (NGF) to recruit nerves and promote the PNI. Activating the HGF/c-Met signaling pathway also enhanced the migration and invasion ability of cancer cells to facilitate cancer cells invading nerves. Mechanistically, HGF/c-Met signaling pathway can active the mTOR/NGF axis to promote the PNI of pancreatic cancer. Additionally, we found that knocking down c-Met expression inhibited cancer cell migration along the nerve, reduced the damage of the sciatic nerve caused by cancer cells and protected the function of the sciatic nerve in vivo. Taken together, our findings suggest a supportive mechanism of the HGF/c-Met signaling pathway in promoting PNI by activating the mTOR/NGF axis in pancreatic cancer. Blocking the HGF/c-Met signaling pathway may be an effective target for the treatment of PNI.
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Fator de Crescimento Neural , Neoplasias Pancreáticas , Movimento Celular , Fator de Crescimento de Hepatócito , Humanos , Invasividade Neoplásica/patologia , Fator de Crescimento Neural/metabolismo , Neoplasias Pancreáticas/patologia , Serina-Treonina Quinases TOR , Neoplasias PancreáticasRESUMO
Emerging evidence suggests that ADP-ribosylation factor like-4c (Arl4c) may be a potential choice for cancer treatment. However, its role in pancreatic cancer, especially in tumor-stroma interactions and drug resistance, is still unknown. In the current study, we examined the proliferation and drug resistance effect of Arl4c on pancreatic cancer cells. Furthermore, we explored the contribution of Arl4c high expression in pancreatic stellate cell (PSC) activation. We found that high Arl4c expression is associated with cell proliferation, drug resistance, and PSC activation. In detail, Arl4c regulates connective tissue growth factor (CTGF) paracrine, further induces autophagic flux in PSCs, resulting in PSC activation. TGFß1 secreted by activated PSCs enhances cancer cell stem cell properties via smad2 signaling, further increasing cell drug resistance. YAP is an important mediator of the Arl4c-CTGF loop. Taken together, these results suggest that Arl4c is essential for pancreatic cancer progression and may be an effective therapeutic choice.
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BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant diseases because of its non-symptomatic tumorigenesis. We previous found heat shock factor 1 (HSF1) was critical for PDAC progression and the aim of this study was to clarified the mechanisms on early activation of HSF1 and its role in the pancreatic cancer tumorigenesis. METHODS: The expression and location of HSF1 on human or mice pancreatic tissues were examined by immunohistochemically staining. We mainly used pancreatic acinar cell 3-dimensional (3D) culture and a spontaneous pancreatic precancerous lesion mouse model called LSL-KrasG12D/+; Pdx1-Cre (KC) (and pancreatitis models derived from KC mice) to explore the pro-tumorigenesis mechanisms of the HSF1 in vitro and in vivo. Bioinformatics and molecular experiments were used to explore the underlying mechanisms between HSF1 and epidermal growth factor receptor (EGFR). RESULTS: In this study, we found that pharmacological inhibition of HSF1 slowed pancreatic cancer initiation and suppressed the pancreatitis-induced formation of pancreatic precancerous lesion. Next, bioinformatics analysis revealed the closely linked between HSF1 and EGFR pathway and we also confirmed their parallel activation in pancreatic precancerous lesions. Besides, the pharmacological inhibition of EGFR suppressed the initiation of pancreatic cancer and the activation of HSF1 in vivo. Indeed, we demonstrated that the EGFR activation that mediated pancreatic cancer tumorigenesis was partly HSF1-dependent in vitro. CONCLUSION: Hence, we concluded that the EGFR-HSF1 axis promoted the initiation of pancreatic cancer.
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Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Receptores ErbB/metabolismo , Animais , Carcinogênese , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos TransgênicosRESUMO
Resveratrol is a natural polyphenolic compound with multiple biological effects, e.g., proliferation inhibition, anti-oxidation, and neuroprotection. Besides that, studies have shown that resveratrol inhibits tumor growth and migration, as well as epithelial-mesenchymal transition (EMT). However, its molecular mechanisms in tumor progression are not fully understood. Nutrient-deprivation autophagy factor-1 (NAF-1) is mainly found in the endoplasmic reticulum and mitochondrial outer membrane. It is an important genetic locus for regulating oxidative stress and autophagy. The molecular mechanism of NAF-1 in pancreatic cancer is currently unclear. The current study found that NAF-1 is expressed in pancreatic cancer tissue and correlated with the progression of pancreatic cancer. Furthermore, we found that NAF-1 inhibition significantly inhibits the stem cell characteristics and the invasion and migration abilities of pancreatic cancer cells. In a subcutaneous xenograft model of pancreatic cancer in nude mice, resveratrol inhibited the expression of NAF-1, thereby inhibiting tumor growth. Taken together, resveratrol could be an effective anti-tumor drug, and NAF-1 may be a rational therapeutic target.
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Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumour with an extremely poor prognosis due to its insidious initiation and a lack of therapeutic strategies. Resveratrol suppresses pancreatic cancer progression and attenuates pancreatitis by modulating multiple targets, including nuclear factor kappa B (NFκB) signalling pathways. However, the effect of resveratrol on pancreatic cancer initiation and its mechanisms remain unclear. In this study, we utilised the LSL-KrasG12D/+; Pdx1-Cre (KC) spontaneous pancreatic precancerous lesion mouse model to explore the anti-tumourigenesis mechanisms of resveratrol in vivo. In vitro acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasias (PanINs) formation assays were performed by pancreatic acinar cell 3-dimensional (3D) culture. Histopathological analysis was used to examine the pathological morphology of pancreatic tissues. Resveratrol prevented the progression of pancreatic precancerous lesions and inhibited the activation of NFκB signalling pathway-related molecules in KC mouse pancreatic tissues. In addition, resveratrol reduced the severity of cerulein-induced pancreatitis and the formation of ADM/PanINs in vivo and in vitro, which may be related to its effect on NFκB inactivation. Furthermore, pancreatic acinar 3D culture demonstrated that activation of the NFκB signalling pathway promoted the formation of ADM/PanINs in vitro, and this initiating effect of NFκB was blocked by resveratrol. Resveratrol slowed the tumourigenesis of pancreatic cancer by inhibiting NFκB activation.
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Carcinogênese/efeitos dos fármacos , Carcinoma Ductal Pancreático/prevenção & controle , NF-kappa B/metabolismo , Resveratrol/farmacologia , Animais , Carcinoma Ductal Pancreático/metabolismo , Células Cultivadas , Ceruletídeo/farmacologia , Proteínas de Homeodomínio/genética , Metaplasia/prevenção & controle , Camundongos , Camundongos Transgênicos , Pancreatite/patologia , Pancreatite/prevenção & controle , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/efeitos dos fármacos , Transativadores/genéticaRESUMO
Pancreatic cancer is characterized by a hypoxic tumor microenvironment, which is primarily caused by massive fibrosis with pancreatic stellate cells (PSCs) as a main component. Our previous studies have shown that resveratrol can significantly inhibit pancreatic cancer. However, whether resveratrol can inhibit hypoxia-induced cancer development remains unclear. The objective of this study was to explore whether PSCs and hypoxia synergistically mediate aggressiveness in pancreatic cancer and detect the potential pleiotropic protective effects of resveratrol on hypoxia-induced pancreatic cancer progression. Human PSCs were treated with vehicle or resveratrol under normoxic or hypoxic conditions (3% O2), and PSC activation was assessed by immunofluorescence staining. SiRNA was used to silence hypoxia-inducible factor 1 (HIF-1) expression. The invasive capacity of Panc-1 and Mia Paca-2 cells cocultured with conditioned medium from PSCs was assessed by Transwell assays. To examine tumor formation kinetics, KPC (LSL-KrasG12D/+, Trp53fl/+, and Pdx1-Cre) mice were sacrificed at different time points. To investigate the antitumor effects of resveratrol in vivo, 8-wk-old KPC mice were divided into two groups and treated daily with or without 50 mg/kg resveratrol. Our data indicate that hypoxia induces PSC activation via HIF-1 and that the interleukin 6, vascular endothelial growth factor A, and stromal cell-derived factor 1 derived from activated PSCs promote both invasion and the epithelial-mesenchymal transition and inhibit apoptosis in pancreatic cancer cells. However, resveratrol inhibits hypoxia-induced PSC activation, blocks the interplay between PSCs and pancreatic cancer cells, and suppresses the malignant progression of pancreatic cancer and stromal desmoplasia in a KPC mouse model. Our data highlight that activated PSCs and intratumoral hypoxia are essential targets for novel strategies to prevent tumor-microenvironment interactions. Furthermore, the polyphenolic compound resveratrol effectively ameliorates the malignant progression of pancreatic ductal adenocarcinoma.
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Adenocarcinoma/tratamento farmacológico , Antioxidantes/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Hipóxia Celular/efeitos dos fármacos , Células Estreladas do Pâncreas/efeitos dos fármacos , Resveratrol/uso terapêutico , Adenocarcinoma/patologia , Antioxidantes/farmacologia , Carcinoma Ductal Pancreático/patologia , Progressão da Doença , Humanos , Resveratrol/farmacologiaRESUMO
BACKGROUND: Diabetes is recognized to be a risk factor of pancreatic cancer, but the mechanism has not been fully elucidated. Sterol regulatory element binding protein 1 (SREBP1) is an important transcription factor involved in both lipid metabolism and tumor progression. However, the relationship between high glucose microenvironment, SREBP1 and pancreatic cancer remains to be explored. METHODS: Clinical data and surgical specimens were collected. Pancreatic cancer cell lines BxPc-3 and MiaPaCa-2 were cultured in specified medium. Immunohistochemistry (IHC) and western blotting were performed to detect the expression of SREBP1. MTT and colony formation assays were applied to investigate cell proliferation. Immunofluorescence, mRFP-GFP adenoviral vector and transmission electron microscopy were performed to evaluate autophagy. We used streptozotocin (STZ) to establish a high glucose mouse model for the in vivo study. RESULTS: We found that high blood glucose levels were associated with poor prognosis in pancreatic cancer patients. SREBP1 was overexpressed in both pancreatic cancer tissues and pancreatic cancer cell lines. High glucose microenvironment promoted tumor proliferation, suppressed apoptosis and inhibited autophagy level by enhancing SREBP1 expression. In addition, activation of autophagy accelerated SREBP1 expression and suppressed apoptosis. Moreover, high glucose promotes tumor growth in vivo by enhancing SREBP1 expression. CONCLUSION: Our results indicate that SREBP1-autophagy axis plays a crucial role in tumor progression induced by high glucose microenvironment. SREBP1 may represent a novel target for pancreatic cancer prevention and treatment.
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Autofagia/genética , Glucose/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Adulto , Idoso , Animais , Apoptose/genética , Glicemia , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Feminino , Expressão Gênica , Xenoenxertos , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Biológicos , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Prognóstico , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismoRESUMO
BACKGROUND: Recent studies have suggested that 85% of pancreatic cancer patients accompanied with impaired glucose tolerance or even Diabetes Mellitus (DM) and the invasive and migratory abilities of pancreatic cancer could be enhanced by high glucose. This study aimed to investigate whether Hypoxia- Inducible Factor-1α (HIF-1α) mediates hyperglycemia-induced pancreatic cancer glycolysis. METHODS: The cellular glycolytic activity was assessed by determining lactate production, glucose uptake and lactate dehydrogenase enzymatic activity. Pancreatic cancer cells (BxPC-3 cells) were transfected with short hairpin RNA targeting the HIF-1α. RESULTS: Hyperglycemia promotes pancreatic cancer glycolysis. Lactate dehydrogenase A (LDHA) activity and hexokinase 2 (HK2), platelet-type of phosphofructokinase (PFKP) expression were significantly upregulated under hyperglycemic conditions. HIF-1α knockdown prominently down-regulated the activity of LDHA and the expression of HK2, PFKP and decreased lactate production in BxPC-3 cells. Under hypoxia condition, hyperglycemia induced pancreatic glycolysis by mechanisms that are both dependent on HIF-1α and independent of it. CONCLUSION: The accumulation of HIF-1α induced by hyperglycemia increases LDHA activity and HK2, PFKP expression, thereby promoting pancreatic glycolysis to facilitate cancer progression.
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Hiperglicemia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Pancreáticas/metabolismo , Hipóxia Celular , Células Cultivadas , Glicólise , Humanos , Neoplasias Pancreáticas/patologiaRESUMO
Microenvironment plays a vital role in tumor progression; we focused on elucidating the role of hepatic stellate cells (HSCs) in hepatocarcinoma (HCC) aggressiveness and investigated the potential protective effect of curcumin on HSC-driven hepatocarcinoma angiogenesis and invasion. Our data suggest that HSCs increase HCC reactive oxygen species (ROS) production to upregulate hypoxia-inducible factor-1α (HIF-1α) expression to promote angiogenesis, epithelial to mesenchymal transition (EMT) process and invasion. And HSCs could secrete soluble factors, such as interleukin-6 (IL-6), vascular endothelial cell growth factor (VEGF), and stromal-derived factor-1 (SDF-1) to facilitate HCC progression. Curcumin could significantly suppress the above HSC-induced effects in HCC and could abrogate ROS and HIF-1α expression in HCC. HIF-1α or connective tissue growth factor (CTGF) knockdown could abolish the aforementioned curcumin affection. Moreover, CTGF is a downstream gene of HIF-1α. In addition, nuclear factor E2-related factor 2 (Nrf2) and glutathione (GSH) are involved in curcumin protection of HCC. These data indicate that curcumin may induce ROS scavenging by upregulating Nrf2 and GSH, thus inhibiting HIF-1α stabilization to suppress CTGF expression to exhibit its protection on HCC. Curcumin has a promising therapeutic effect on HCC. CTGF is responsible for curcumin-induced protection in HCC.
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Carcinoma Hepatocelular/tratamento farmacológico , Fator de Crescimento do Tecido Conjuntivo/genética , Curcumina/uso terapêutico , Regulação para Baixo , Células Estreladas do Fígado/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Quimiocina CXCL12/metabolismo , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Curcumina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Glutationa/metabolismo , Células Hep G2 , Células Estreladas do Fígado/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Interleucina-6/metabolismo , Neoplasias Hepáticas/patologia , Metaloproteinase 9 da Matriz/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Invasividade Neoplásica , Neovascularização Patológica/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Resveratrol is a type of polyphenol that is abundantly present in knotweed and grapes, and has been confirmed to have tumorinhibitory properties. However, the effect of resveratrol on tumor cells under chronic stress conditions remains unclear. The aim of the present study was to demonstrate that resveratrol exerts a significant inhibitory effect on the growth and proliferation of tumor cells under chronic stress in a dosedependent manner. Furthermore, resveratrol was able to induce apoptosis of cancer cells under chronic stress conditions. Moreover, resveratrol was found to inhibit tumor cells under chronic stress by decreasing the expression of the ß2adrenergic receptor (ADRB2); in addition, the protein expression of hypoxiainducible factor (HIF)1α was suppressed by resveratrol in a dosedependent manner. Thus, these data suggest that resveratrol inhibits the growth of cancer cells under chronic stress by regulating the ADRB2HIF1α axis. In summary, the present study may provide a new basis supporting the use of resveratrol for the prevention and treatment of pancreatic cancer.
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Antineoplásicos Fitogênicos/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias/tratamento farmacológico , Receptores Adrenérgicos beta 2/metabolismo , Resveratrol/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias/patologia , Resveratrol/uso terapêuticoRESUMO
Pancreatic stellate cells (PSCs), a key component of the tumor microenvironment, contribute to tumor invasion, metastasis, and chemoresistance. Osteopontin (OPN), a phosphorylated glycoprotein, is overexpressed in pancreatic cancer. However, OPN expression in PSCs and its potential roles in tumor-stroma interactions remain unclear. The present study first showed that OPN is highly expressed and secreted in activated PSCs driven by hypoxia, and this process is in a ROS-dependent manner; in addition, OPN was shown to be involved in the PSC-induced epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC)-like properties of pancreatic cancer cells (PCCs). Mechanistically, OPN from activated PSCs interacts with the transmembrane receptor integrin αvß3 on PCCs to upregulate forkhead box protein M1 (FOXM1) expression and induce malignant phenotypes of PCCs. Moreover, the Akt and Erk pathways participate in OPN/integrin αvß3 axis-induced FOXM1 expression of PCCs. Our further analysis showed that OPN and FOXM1 are significantly upregulated in pancreatic cancer tissues and are associated with poor clinical outcome, indicating that OPN and FOXM1 might be considered as diagnostic and prognostic biomarkers for patients with pancreatic cancer. In conclusion, we show here for the first time that OPN promotes the EMT and CSC-like properties of PCCs by activating the integrin αvß3-Akt/Erk-FOXM1 cascade in a paracrine manner, suggesting that targeting the tumor microenvironment represents a promising therapeutic strategy in pancreatic cancer.
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Transição Epitelial-Mesenquimal , Proteína Forkhead Box M1/metabolismo , Integrina alfaVbeta3/metabolismo , Células-Tronco Neoplásicas/metabolismo , Osteopontina/metabolismo , Neoplasias Pancreáticas/patologia , Comunicação Parácrina , Hipóxia Tumoral , Adulto , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/patologia , Neoplasias Pancreáticas/metabolismo , Células Estreladas do Pâncreas/metabolismo , Células Estreladas do Pâncreas/patologia , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Adulto JovemRESUMO
Cancer stem cells (CSCs), which are found in various types of human cancer, including pancreatic cancer, possess elevated metastatic potential, lead to tumor recurrence and cause chemoradiotherapy resistance. Alterations in cellular bioenergetics through the regulation of 5' adenosine monophosphateactivated protein kinase (AMPK) signaling may be a prerequisite to stemness. Betulinic acid (BA) is a wellknown bioactive compound with antiretroviral and antiinflammatory potential, which has been reported to exert anticancer effects on various types of cancer, including pancreatic cancer. The present study aimed to investigate whether BA could inhibit pancreatic CSCs via regulation of AMPK signaling. The proliferation of pancreatic cancer cells was examined by MTT and colony formation assays. The migratory and invasive abilities of pancreatic cancer cells were assessed using woundscratch and Transwell invasion assays. In addition, the expression levels of candidate genes were measured by reverse transcriptionquantitative polymerase chain reaction and western blotting. The results revealed that BA inhibited the proliferation and tumorsphere formation of pancreatic cancer cells, suppressed epithelialmesenchymal transition (EMT), migration and invasion, and reduced the expression of three pluripotency factors [SRYbox 2 (Sox2), octamerbinding protein 4 (Oct4) and Nanog]. Furthermore, immunohistochemical analysis confirmed that there was a significant inverse association between the expression levels of phosphorylated (P)AMPK and Sox2 in pancreatic cancer, and it was revealed that BA may activate AMPK signaling. Notably, knockdown of AMPK reversed the suppressive effects of BA on EMT and stemness of pancreatic cancer cells. In addition, BA reversed the effects of gemcitabine on stemness and enhanced the sensitivity of pancreatic cancer cells to gemcitabine. Collectively, these results indicated that BA may effectively inhibit pluripotency factor expression (Sox2, Oct4 and Nanog), EMT and the stemlike phenotype of pancreatic cancer cells via activating AMPK signaling. Therefore, BA may be considered an attractive therapeutic candidate and an effective inhibitor of the stemlike phenotype in pancreatic cancer cells. Further investigation into the development of BA as an anticancer drug is warranted.
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Antineoplásicos Fitogênicos/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Pancreáticas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triterpenos/farmacologia , Adenilato Quinase/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Neoplásicas/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Triterpenos Pentacíclicos , Fosforilação , Fatores de Transcrição SOXB1/metabolismo , Ácido BetulínicoRESUMO
OBJECTIVES: Gemcitabine is a standard treatment for advanced pancreatic cancer patients but can cause chemoresistance during treatment. The chemoresistant cells have features of cancer stem cells (CSCs). Resveratrol has been reported to overcome the resistance induced by gemcitabine. However, the mechanism by which resveratrol enhances chemosensitivity remains elusive. Here, we explored the mechanism by which resveratrol enhanced chemosensitivity and the role of sterol regulatory element binding protein 1 (SREBP1) in gemcitabine-induced stemness. MATERIALS AND METHODS: The pancreatic cancer cell lines MiaPaCa-2 and Panc-1 were treated under different conditions. Methyl thiazolyl tetrazolium and colony formation assays were performed to evaluate effects on proliferation. Flow cytometry was conducted to detect apoptosis. Oil red O staining was performed to examine lipid synthesis. The sphere formation assay was applied to investigate the stemness of cancer cells. Immunohistochemistry was performed on tumour tissue obtained from treated KPC mice. RESULTS: Resveratrol enhanced the sensitivity of gemcitabine and inhibited lipid synthesis via SREBP1. Knockdown of SREBP1 limited the sphere formation ability and suppressed the expression of CSC markers. Furthermore, suppression of SREBP1 induced by resveratrol reversed the gemcitabine-induced stemness. These results were validated in a KPC mouse model. CONCLUSIONS: Our data provide evidence that resveratrol reverses the stemness induced by gemcitabine by targeting SREBP1 both in vitro and in vivo. Thus, resveratrol can be an effective chemotherapy sensitizer, and SREBP1 may be a rational therapeutic target.
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Antimetabólitos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Resveratrol/farmacologia , Proteína de Ligação a Elemento Regulador de Esterol 1/antagonistas & inibidores , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/farmacologia , Humanos , Lipídeos/biossíntese , Camundongos , Camundongos Transgênicos , Células-Tronco Neoplásicas/efeitos dos fármacos , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Interferência de RNA , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , GencitabinaRESUMO
BACKGROUND/AIMS: Sulforaphane (SFN) is known for its potent bioactive properties, such as anti-inflammatory and anti-tumor effects. However, its anti-tumor effect on pancreatic cancer is still poorly understood. In the present study, we explored the therapeutic potential of SFN for pancreatic cancer and disclosed the underlying mechanism. METHODS: Panc-1 and MiaPaca-2 cell lines were used in vitro. The biological function of SFN in pancreatic cancer was measured using EdU staining, colony formation, apoptosis, migration and invasion assays. Reactive oxygen species (ROS) production was measured using 2'-7'-Dichlorofluorescein diacetate (DCF-DA) fluorometric analysis. Western blotting and immunofluorescence were used to measure the protein levels of p-AMPK and epithelial-mesenchymal transition (EMT) pathway-related proteins, and cellular translocation of nuclear factor erythroid 2-related factor 2 (Nrf2). Nude mice and transgenic pancreatic cancer mouse model were used to measure the therapeutic potential of SFN on pancreatic cancer. RESULTS: SFN can inhibit pancreatic cancer cell growthï¼ promote apoptosis, curb colony formation and temper the migratory and invasion ability of pancreatic cancer cells. Mechanistically, excessive ROS production induced by SFN activated AMPK signaling and promoted the translocation of Nrf2, resulting in cell viability inhibition of pancreatic cancer. Pretreatment with compound C, a small molecular inhibitor of AMPK signaling, reversed the subcellular translocation of Nrf2 and rescued cell invasion ability. With nude mice and pancreatic cancer transgenic mouse, we identified SFN could inhibit tumor progression, with smaller tumor size and slower tumor progression in SFN treatment group. CONCLUSION: Our study not only elucidates the mechanism of SFN-induced inhibition of pancreatic cancer in both normal and high glucose condition, but also testifies the dual-role of ROS in pancreatic cancer progression. Collectively, our research suggests that SFN may serve as a potential therapeutic choice for pancreatic cancer.