Adaptation of pancreatic cancer cells to nutrient deprivation is reversible and requires glutamine synthetase stabilization by mTORC1

Pancreatic ductal adenocarcinoma (PDA) is a lethal, therapy-resistant cancer that thrives in a highly desmoplastic, nutrient-deprived microenvironment. Several studies investigated the effects of depriving PDA of either glucose or glutamine alone. However, the consequences on PDA growth and metabolism of limiting both preferred nutrients have remained largely unknown. Here, we report the selection for clonal human PDA cells that survive and adapt to limiting levels of both glucose and glutamine. We find that adapted clones exhibit increased growth in vitro and enhanced tumor-forming capacity in vivo. Mechanistically, adapted clones share common transcriptional and metabolic programs, including amino acid use for de novo glutamine and nucleotide synthesis. They also display enhanced mTORC1 activity that prevents the proteasomal degradation of glutamine synthetase (GS), the rate-limiting enzyme for glutamine synthesis. This phenotype is notably reversible, with PDA cells acquiring alterations in open chromatin upon adaptation. Silencing of GS suppresses the enhanced growth of adapted cells and mitigates tumor growth. These findings identify nongenetic adaptations to nutrient deprivation in PDA and highlight GS as a dependency that could be targeted therapeutically in pancreatic cancer patients.

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Adaptation of pancreatic cancer cells to nutrient deprivation is reversible and requires glutamine synthetase stabilization by mTORC1

10.1101/2020.02.16.951681 ◽

2020 ◽

Author(s):

Pei-Yun Tsai ◽

Min-Sik Lee ◽

Unmesh Jadhav ◽

Insia Naqvi ◽

Shariq Madha ◽

...

Keyword(s):

Pancreatic Cancer ◽

Glutamine Synthetase ◽

Tumor Growth ◽

Pancreatic Ductal Adenocarcinoma ◽

Cancer Cells ◽

Ductal Adenocarcinoma ◽

Nutrient Deprivation ◽

Open Chromatin ◽

Nucleotide Synthesis ◽

Pancreatic Cancer Cells

AbstractPancreatic ductal adenocarcinoma (PDA) is a lethal, therapy-resistant cancer that thrives in a highly desmoplastic, nutrient-deprived microenvironment. Several studies investigated the effects of depriving PDA of either glucose or glutamine alone. However, the consequences on PDA growth and metabolism of limiting both preferred nutrients have remained largely unknown. Here, we report the selection for clonal human PDA cells that survive and adapt to limiting levels of both glucose and glutamine. We find that adapted clones exhibit increased growth in vitro and enhanced tumor-forming capacity in vivo. Mechanistically, adapted clones share common transcriptional and metabolic programs, including amino acid use for de novo glutamine and nucleotide synthesis. They also display enhanced mTORC1 activity that prevents the proteasomal degradation of glutamine synthetase (GS), the rate-limiting enzyme for glutamine synthesis. This phenotype is notably reversible, with PDA cells acquiring alterations in open chromatin upon adaptation. Silencing of GS suppresses the enhanced growth of adapted cells and mitigates tumor growth. These findings identify non-genetic adaptations to nutrient deprivation in PDA and highlight GS as a dependency that could be targeted therapeutically in pancreatic cancer patients.SignificancePancreatic ductal adenocarcinoma (PDA) is a highly lethal malignancy with no effective therapies. PDA aggressiveness partly stems from its ability to grow within a uniquely dense stroma restricting nutrient access. This study demonstrates that PDA clones that survive chronic nutrient deprivation acquire reversible non-genetic adaptations allowing them to switch between metabolic states optimal for growth under nutrient-replete or nutrient-deprived conditions. One contributing factor to this adaptation mTORC1 activation, which stabilizes glutamine synthetase (GS) necessary for glutamine generation in nutrient-deprived cancer cells. Our findings imply that although total GS levels may not be a prognostic marker for aggressive disease, GS inhibition is of high therapeutic value, as it targets specific cell clusters adapted to nutrient starvation, thus mitigating tumor growth.

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NR5A2 transcriptional activation by BRD4 promotes pancreatic cancer progression by upregulating GDF15

Cell Death Discovery ◽

10.1038/s41420-021-00462-8 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Feng Guo ◽

Yingke Zhou ◽

Hui Guo ◽

Dianyun Ren ◽

Xin Jin ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cancer Cells ◽

Cancer Progression ◽

Transcriptional Activation ◽

Ductal Adenocarcinoma ◽

Pancreatic Cancer Cells ◽

Gene Sets ◽

And Migration

AbstractNR5A2 is a transcription factor regulating the expression of various oncogenes. However, the role of NR5A2 and the specific regulatory mechanism of NR5A2 in pancreatic ductal adenocarcinoma (PDAC) are not thoroughly studied. In our study, Western blotting, real-time PCR, and immunohistochemistry were conducted to assess the expression levels of different molecules. Wound-healing, MTS, colony formation, and transwell assays were employed to evaluate the malignant potential of pancreatic cancer cells. We demonstrated that NR5A2 acted as a negative prognostic biomarker in PDAC. NR5A2 silencing inhibited the proliferation and migration abilities of pancreatic cancer cells in vitro and in vivo. While NR5A2 overexpression markedly promoted both events in vitro. We further identified that NR5A2 was transcriptionally upregulated by BRD4 in pancreatic cancer cells and this was confirmed by Chromatin immunoprecipitation (ChIP) and ChIP-qPCR. Besides, transcriptome RNA sequencing (RNA-Seq) was performed to explore the cancer-promoting effects of NR5A2, we found that GDF15 is a component of multiple down-regulated tumor-promoting gene sets after NR5A2 was silenced. Next, we showed that NR5A2 enhanced the malignancy of pancreatic cancer cells by inducing the transcription of GDF15. Collectively, our findings suggest that NR5A2 expression is induced by BRD4. In turn, NR5A2 activates the transcription of GDF15, promoting pancreatic cancer progression. Therefore, NR5A2 and GDF15 could be promising therapeutic targets in pancreatic cancer.

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Hyperglycemia Promotes Pancreatic Cancer Initiation and Progression by Activating the Wnt/β-Catenin Signaling Pathway

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520621666210201095613 ◽

2021 ◽

Vol 21 ◽

Author(s):

Huiming Chen ◽

Junfeng Zhao ◽

Ningning Jiang ◽

Zheng Wang ◽

Chang Liu

Keyword(s):

Pancreatic Cancer ◽

Signaling Pathway ◽

Precancerous Lesions ◽

Clinical Specimen ◽

Ductal Adenocarcinoma ◽

Dependent Manner ◽

Pancreatic Cancer Cells ◽

Cancer Initiation

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal diseases, with a 5-year survival rate of less than 10% because of the limited knowledge of tumor-promoting factors and their underlying mechanism. Diabetes mellitus (DM) and hyperglycemia are risk factors for many cancers, including PDAC, that modulate multiple downstream signaling pathways, such as the wingless/integrated (Wnt)/β-catenin signaling pathway. However, whether hyperglycemia promotes PDAC initiation and progression by activating the Wnt/β-catenin signaling pathway remains unclear. Methods: In this study, we used bioinformatics analysis and clinical specimen analysis to evaluate the activation states of the Wnt/βcatenin signaling pathway. In addition, colony formation assays, Transwell assays and wound-healing assays were used to evaluate the malignant biological behaviors of pancreatic cancer cells (PCs) under hyperglycemic conditions. To describe the effects of hyperglycemia and the Wnt/β-catenin signaling pathway on the initiation of PDAC, we used pancreatitis-driven pancreatic cancer initiation models in vivo and pancreatic acinar cell 3-dimensional culture in vitro. Results: Wnt/β-catenin signaling pathway-related molecules were overexpressed in PDAC tissues/cells and correlated with poor prognosis in PDAC patients. In addition, hyperglycemia exacerbated the abnormal activation of β-catenin in PDAC and enhanced the malignant biological behaviors of PCs in a Wnt/β-catenin signaling pathway-dependent manner. Indeed, hyperglycemia accelerated the formation of pancreatic precancerous lesions by activating the Wnt/β-catenin signaling pathway in vivo and in vitro. Conclusion: Hyperglycemia promotes pancreatic cancer initiation and progression by activating the Wnt/β-catenin signaling pathway.

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Targeted intervention of eIF4A1 inhibits EMT and metastasis of pancreatic cancer cells via c-MYC/miR-9 signaling

Cancer Cell International ◽

10.1186/s12935-021-02390-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yuchong Zhao ◽

Yun Wang ◽

Wei Chen ◽

Shuya Bai ◽

Wang Peng ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cancer Cells ◽

The Cancer Genome Atlas ◽

Ductal Adenocarcinoma ◽

Mesenchymal Transition ◽

Early Metastasis ◽

Pancreatic Cancer Cells ◽

E Cadherin

Abstract Background Owing to the lack of effective treatment options, early metastasis remains the major cause of pancreatic ductal adenocarcinoma (PDAC) recurrence and mortality. However, the molecular mechanism of early metastasis is largely unknown. We characterized the function of eukaryotic translation initiation factors (eIFs) in epithelial-mesenchymal-transition (EMT) and metastasis in pancreatic cancer cells to investigate whether eIFs and downstream c-MYC affect EMT and metastasis by joint interference. Methods We used The Cancer Genome Atlas (TCGA) and Genome Tissue Expression (GTEx) databases to analyze eIF4A1 expression in PDAC tissues and further validated the findings with a microarray containing 53 PDAC samples. Expression regulation and pharmacological inhibition of eIF4A1 and c-MYC were performed to determine their role in migration, invasion, and metastasis in pancreatic cancer cells in vitro and in vivo. Results Elevated eIF4A1 expression was positively correlated with lymph node infiltration, tumor size, and indicated a poor prognosis. eIF4A1 decreased E-cadherin expression through the c-MYC/miR-9 axis. Loss of eIF4A1 and c-MYC decreased the EMT and metastasis capabilities of pancreatic cancer cells, whereas upregulation of eIF4A1 attenuated the inhibition of EMT and metastasis induced by c-MYC downregulation. Treatment with the eIF4A1 inhibitor rocaglamide (RocA) or the c-MYC inhibitor Mycro3 either alone or in combination significantly decreased the expression level of EMT markers in pancreatic cancer cells in vitro. However, the efficiency and safety of RocA alone were not inferior to those of the combination treatment in vivo. Conclusion Overexpression of eIF4A1 downregulated E-cadherin expression through the c-MYC/miR-9 axis, which promoted EMT and metastasis of pancreatic cancer cells. Despite the potential feedback loop between eIF4A1 and c-MYC, RocA monotherapy is a promising treatment inhibiting eIF4A1-induced PDAC metastasis.

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STAT1-mediated inhibition of FOXM1 enhances gemcitabine sensitivity in pancreatic cancer

Clinical Science ◽

10.1042/cs20180816 ◽

2019 ◽

Vol 133 (5) ◽

pp. 645-663 ◽

Cited By ~ 10

Author(s):

Chao Liu ◽

Jiaqi Shi ◽

Qingwei Li ◽

Zhiwei Li ◽

Changjie Lou ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cancer Cells ◽

Immunohistochemical Analysis ◽

Human Pancreatic Cancer ◽

Ductal Adenocarcinoma ◽

Luciferase Reporter ◽

Pancreatic Cancer Cells ◽

Foxm1 Expression

Abstract Forkhead box protein M1 (FOXM1) was identified as an oncogenic transcription factor and master regulator of tumor progression and metastasis. FOXM1 expression often correlates with poor prognosis and chemotherapy resistance. In the present study, we investigated the association of FOXM1 expression and chemoresistance in pancreatic cancer. Elevated FOXM1 protein levels were associated with gemcitabine chemoresistance in patients with pancreatic cancer. In gemcitabine resistance cell line models of pancreatic cancer, FOXM1 expression increased, which induced gemcitabine chemoresistance in vitro. In pancreatic cancer cells treated with gemcitabine, FOXM1 affected nuclear factor κB (NF-κB) signaling activity. Immunohistochemical analysis demonstrated a negative association of FOXM1 expression and the level of phosphorylated signal transducer and activator of transcription 1 (pSTAT1) in human pancreatic cancer tissues. Dual-luciferase reporter assays and chromatin-immunoprecipitation assays demonstrated that pSTAT1 directly binds to the FOXM1 promoter to down-regulate its transcription. Interferon γ (IFNγ) promoted gemcitabine-induced cell apoptosis and inhibited cell proliferation in vitro and in vivo by FOXM1 inhibition. These data suggested that FOXM1 enhances chemoresistance to gemcitabine in pancreatic cancer. IFNγ could be used to down-regulate the expression of FOXM1 through STAT1 phosphorylation, thereby increasing the sensitivity of pancreatic cancer cells to gemcitabine. These studies suggested the sensitization by IFNγ in pancreatic ductal adenocarcinoma (PDAC) chemotherapy, which requires further clinical studies.

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TMPRSS4 Promotes Cell Proliferation and Inhibits Apoptosis in Pancreatic Ductal Adenocarcinoma by Activating ERK1/2 Signaling Pathway

Frontiers in Oncology ◽

10.3389/fonc.2021.628353 ◽

2021 ◽

Vol 11 ◽

Author(s):

Jianyou Gu ◽

Wenjie Huang ◽

Junfeng Zhang ◽

Xianxing Wang ◽

Tian Tao ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cell Proliferation ◽

Pancreatic Ductal Adenocarcinoma ◽

Signaling Pathway ◽

Cellular Proliferation ◽

Function Analysis ◽

Ductal Adenocarcinoma ◽

Pancreatic Cancer Cells

Transmembrane protease serine 4 (TMPRSS4) is upregulated in various kinds of human cancers, including pancreatic cancer. However, its biological function in pancreatic ductal adenocarcinoma (PDAC) remains unclear. In the current study, real-time qPCR, immunohistochemical staining, Western blotting, and database (Cancer Genome Atlas and Gene Expression) analysis revealed remarkable overexpression of TMPRSS4 in PDAC tissue as compared to non-tumor tissue. The TMPRSS4 overexpression was associated with poor prognosis of PDAC patients. Moreover, multivariate analysis revealed that TMPRSS4 serves as an independent risk factor in PDAC. We performed gain-and loss-of-function analysis and found that TMPRSS4 promotes cellular proliferation and inhibits apoptosis of PDAC cells both in vitro and in vivo. Furthermore, we showed that TMPRSS4 might promote cell proliferation and inhibit apoptosis through activating ERK1/2 signaling pathway in pancreatic cancer cells. These findings were validated by using ERK1/2 phosphorylation inhibitor SCH772984 both in vitro and in vivo. Taken together, this study suggests that TMPRSS4 is a proto-oncogene, which promotes initiation and progression of PDAC by controlling cell proliferation and apoptosis. Our findings indicate that TMPRSS4 could be a promising prognostic biomarker and a therapeutic target for the treatment of pancreatic cancer.

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HGF/MET Axis Induces Tumor Secretion of Tenascin-C and Promotes Stromal Rewiring in Pancreatic Cancer

Cancers ◽

10.3390/cancers13143519 ◽

2021 ◽

Vol 13 (14) ◽

pp. 3519

Author(s):

Chiara Modica ◽

Martina Olivero ◽

Francesca Zuppini ◽

Melissa Milan ◽

Cristina Basilico ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cancer Cells ◽

Stellate Cells ◽

Pancreatic Stellate Cells ◽

Ductal Adenocarcinoma ◽

Stromal Compartment ◽

Tenascin C ◽

Pancreatic Cancer Cells

Pancreatic ductal adenocarcinoma is an aggressive tumor characterized by the presence of an abundant stromal compartment contributing significantly to the malignant phenotype. Pancreatic stellate cells are peculiar fibroblasts present in the stroma and represent the predominant source of extracellular matrix proteins, pro-inflammatory cytokines, and growth factors, including hepatocyte growth factor (HGF). Exploiting a co-culture system of human pancreatic stellate cells and cancer cells, we demonstrated that fibroblast activation was reduced upon HGF/MET axis inhibition. To unveil the signaling pathways sustaining stroma modulation orchestrated by MET activation in the tumor, we analyzed the gene expression profile in pancreatic cancer cells stimulated with HGF and treated with HGF/MET inhibitors. Transcriptome analysis showed that, among all the genes modulated by HGF, a subset of 125 genes was restored to the basal level following treatment with the inhibitors. By examining these genes via ingenuity pathway analysis, tenascin C emerged as a promising candidate linking MET signaling and tumor microenvironment. MET-dependent tenascin C modulation in pancreatic cancer cells was validated at RNA and protein levels both in vitro and in vivo. In conclusion, this work identifies tenascin C as a gene modulated by MET activation, suggesting a role in MET-mediated tumor-stroma interplay occurring during pancreatic tumor progression.

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In Vitro and In Vivo Antitumor Efficacy of Docetaxel and Sorafenib Combination in Human Pancreatic Cancer Cells

Current Cancer Drug Targets ◽

10.2174/1568210204916170096 ◽

2010 ◽

Vol 999 (999) ◽

pp. 1-11

Author(s):

P. Ulivi ◽

C. Arienti ◽

W. Zoli ◽

M. Scarsella ◽

S. Carloni ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cancer Cells ◽

Antitumor Efficacy ◽

Human Pancreatic Cancer ◽

Pancreatic Cancer Cells

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Cyathus striatus Extract Induces Apoptosis in Human Pancreatic Cancer Cells and Inhibits Xenograft Tumor Growth In Vivo

Cancers ◽

10.3390/cancers13092017 ◽

2021 ◽

Vol 13 (9) ◽

pp. 2017

Author(s):

Lital Sharvit ◽

Rinat Bar-Shalom ◽

Naiel Azzam ◽

Yaniv Yechiel ◽

Solomon Wasser ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cancer Cells ◽

Pancreatic Cancer Cell Line ◽

Cancer Cell Line ◽

Culture Liquid ◽

Human Pancreatic Cancer ◽

P53 Signaling ◽

Pancreatic Cancer Cells

Pancreatic cancer is a highly lethal disease with limited options for effective therapy and the lowest survival rate of all cancer forms. Therefore, a new, effective strategy for cancer treatment is in need. Previously, we found that a culture liquid extract of Cyathus striatus (CS) has a potent antitumor activity. In the present study, we aimed to investigate the effects of Cyathus striatus extract (CSE) on the growth of pancreatic cancer cells, both in vitro and in vivo. The proliferation assay (XTT), cell cycle analysis, Annexin/PI staining and TUNEL assay confirmed the inhibition of cell growth and induction of apoptosis by CSE. A Western blot analysis demonstrated the involvement of both the extrinsic and intrinsic apoptosis pathways. In addition, a RNAseq analysis revealed the involvement of the MAPK and P53 signaling pathways and pointed toward endoplasmic reticulum stress induced apoptosis. The anticancer activity of the CSE was also demonstrated in mice harboring pancreatic cancer cell line-derived tumor xenografts when CSE was given for 5 weeks by weekly IV injections. Our findings suggest that CSE could potentially be useful as a new strategy for treating pancreatic cancer.

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