scholarly journals Pancreatic ductal adenocarcinoma cells employ integrin α6β4 to form hemidesmosomes and regulate cell proliferation

2021 ◽  
Author(s):  
Jon D Humphries ◽  
Junzhe Zha ◽  
Jessica Burns ◽  
Janet A Askari ◽  
Christopher R Below ◽  
...  

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis due to its aggressive progression, late detection and lack of druggable driver mutations, which often combine to result in unsuitability for surgical intervention. Together with activating mutations of the small GTPase KRas, which are found in over 90% of PDAC tumours, a contributory factor for PDAC tumour progression is formation of a rigid extracellular matrix (ECM) and associated desmoplasia. This response leads to aberrant integrin signalling, and accelerated proliferation and invasion. To identify the integrin adhesion systems that operate in PDAC, we analysed a range of pancreatic ductal epithelial cell models using 2D, 3D and organoid culture systems. Proteomic analysis of isolated integrin receptor complexes from human pancreatic ductal epithelial (HPDE) cells predominantly identified integrin α6β4 and hemidesmosome components, rather than classical focal adhesion components. Electron microscopy, together with immunofluorescence, confirmed the formation of hemidesmosomes by HPDE cells, both in 2D and 3D culture systems. Similar results were obtained for the human PDAC cell line, SUIT-2. Analysis of HPDE cell secreted proteins and cell-derived matrices (CDM) demonstrated that HPDE cells secrete a range of laminin subunits and form a hemidesmosome-specific, laminin 332-enriched ECM. Expression of mutant KRas (G12V) did not affect hemidesmosome composition or formation by HPDE cells. Cell-ECM contacts formed by mouse and human PDAC organoids were also assessed by electron microscopy. Organoids generated from both the PDAC KPC mouse model and human patient-derived PDAC tissue displayed features of acinar-ductal cell polarity, and hemidesmosomes were visible proximal to prominent basement membranes. Furthermore, electron microscopy identified hemidesmosomes in normal human pancreas. Depletion of integrin β4 using siRNA reduced cell proliferation in both SUIT-2 and HPDE cells, reduced the number of SUIT-2 cells in S-phase, and induced G1 cell cycle arrest, indicating a requirement for α6β4-mediated adhesion for cell cycle progression and growth. Taken together, these data suggest that laminin-binding adhesion mechanisms in general, and hemidesmosome-mediated adhesion in particular, may be under-appreciated in the context of PDAC.

2017 ◽  
Vol 8 (16) ◽  
pp. 3154-3165 ◽  
Author(s):  
Chao-qin Shen ◽  
Ting-Ting Yan ◽  
Wei Liu ◽  
Xiao-qiang Zhu ◽  
Xiang-long Tian ◽  
...  

2016 ◽  
Vol 38 (6) ◽  
pp. 2366-2374 ◽  
Author(s):  
Wenzhuo Yang ◽  
Yanning Yang ◽  
Lu Xia ◽  
Yuefeng Yang ◽  
Fei Wang ◽  
...  

Background/Aims: MicroRNAs (miRNAs, miRs) have emerged as critical regulators of cancer cell proliferation. The effect of miR-221 on cancer cell growth could be significantly changeable in different cell lines. Although miR-221 was reported to promote the cell growth of pancreatic ductal adenocarcinoma (PDAC) cells, its role in Capan-2 cell line is largely unknown. Methods: Capan-2 cells were transfected with miR-221 mimics, inhibitors, or negative controls. Cell Counting Kit-8 was used to determine cell viability. EdU staining and cell cycle analysis were used to measure cell proliferation. Western blotting was used to detect the expression levels of PTEN and phospho-Akt. The PI3K-Akt pathway activator SC-79 and inhibitor LY294002 were used to perform the rescue experiment in determining cell proliferation. Results: Overexpressing miR-221 significantly increased cell vitality and promoted cell proliferation and G1-to-S phase transition of the cell cycle in Capan-2 cells, while inhibition of miR-221 decreased that. The protein level of PTEN in Capan-2 cells was downregulated by overexpressing miR-221, while upregulated by inhibiting miR-221. Consistently, enhanced phosphorylation of AktSer473 was observed in miR-221 overexpressed Capan-2 cells, and the opposite result was found in miR-221 inhibited cells. LY294002 restored the pro-proliferation effect of miR-221 on Capan-2 cells, while SC-79 had no additional effect on cell proliferation in Capan-2 cells transfected with miR-221 mimics. Conclusion: Our study indicates that miR-221 is an oncogenic miRNA which promotes Capan-2 cells proliferation by targeting PTEN-Akt pathway.


2017 ◽  
Vol 313 (5) ◽  
pp. G524-G536 ◽  
Author(s):  
Sandrina Maertin ◽  
Jason M. Elperin ◽  
Ethan Lotshaw ◽  
Matthias Sendler ◽  
Steven D. Speakman ◽  
...  

Pancreatic ductal adenocarcinoma (PDAC) displays extensive and poorly vascularized desmoplastic stromal reaction, and therefore, pancreatic cancer (PaCa) cells are confronted with nutrient deprivation and hypoxia. Here, we investigate the roles of autophagy and metabolism in PaCa cell adaptation to environmental stresses, amino acid (AA) depletion, and hypoxia. It is known that in healthy cells, basal autophagy is at a low level, but it is greatly activated by environmental stresses. By contrast, we find that in PaCa cells, basal autophagic activity is relatively high, but AA depletion and hypoxia activate autophagy only weakly or not at all, due to their failure to inhibit mechanistic target of rapamycin. Basal, but not stress-induced, autophagy is necessary for PaCa cell proliferation, and AA supply is even more critical to maintain PaCa cell growth. To gain insight into the underlying mechanisms, we analyzed the effects of autophagy inhibition and AA depletion on PaCa cell metabolism. PaCa cells display mixed oxidative/glycolytic metabolism, with oxidative phosphorylation (OXPHOS) predominant. Both autophagy inhibition and AA depletion dramatically decreased OXPHOS; furthermore, pharmacologic inhibitors of OXPHOS suppressed PaCa cell proliferation. The data indicate that the maintenance of OXPHOS is a key mechanism through which autophagy and AA supply support PaCa cell growth. We find that the expression of oncogenic activation mutation in GTPase Kras markedly promotes basal autophagy and stimulates OXPHOS through an autophagy-dependent mechanism. The results suggest that approaches aimed to suppress OXPHOS, particularly through limiting AA supply, could be beneficial in treating PDAC. NEW & NOTEWORTHY Cancer cells in the highly desmoplastic pancreatic ductal adenocarcinoma confront nutrient [i.e., amino acids (AA)] deprivation and hypoxia, but how pancreatic cancer (PaCa) cells adapt to these conditions is poorly understood. This study provides evidence that the maintenance of mitochondrial function, in particular, oxidative phosphorylation (OXPHOS), is a key mechanism that supports PaCa cell growth, both in normal conditions and under the environmental stresses. OXPHOS in PaCa cells critically depends on autophagy and AA supply. Furthermore, the oncogenic activation mutation in GTPase Kras upregulates OXPHOS through an autophagy-dependent mechanism.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Jing Chen ◽  
Cui-Cui Zhao ◽  
Fei-Ran Chen ◽  
Guo-Wei Feng ◽  
Fei Luo ◽  
...  

Background. Pancreatic cancer is a malignant tumor of the digestive tract, which is difficult to diagnose and treat due to bad early diagnosis. We aimed to explore the role of kinesin superfamily 4A (KIF4A) in pancreatic ductal adenocarcinoma (PDAC). Methods. We first used the bioinformatic website to screen the data of pancreatic cancer in TCGA, and KIF4A protein was detected among the 86 specimens of patients in our hospital combined with clinic-pathological characteristics and survival analysis. KIF4A loss-expression cell lines were established by RNA interference (RNAi). In addition, we performed in vitro cell assays to detect the changes in cell proliferation, migration, and invasion. The proteins involved in the proliferation and metastasis of cancer cells were also detected by western blot. The above results could be proved in vivo. Further, the correlation between KIF4A and CDC5L was analyzed by TCGA and IHC data. Results. We first found a high expression of KIF4A in pancreatic cancer, suggesting a role of KIF4A in the development of pancreatic cancer. KIF4A was found to be differentially expressed ( P < 0.05 ) among the 86 specimens of patients in our hospital and was significantly associated with PDAC TNM stages and tumor size. High KIF4A expression also significantly worsened overall survival (OS) and disease-free survival rate (DFS) ( P < 0.05 , respectively). In addition, cell proliferation, migration, and invasion were inhibited by the KIF4A-shRNA group compared with the control ( P < 0.05 , respectively). In the end, knockdown of KIF4A could inhibit tumor development and metastasis in vivo. Further, the positive correlation between KIF4A and CDC5L existed, and KIF4A might promote pancreatic cancer proliferation by affecting CDC5L expression. Conclusion. In conclusion, the high expression level of KIF4A in PDAC was closely related to poor clinical and pathological status, lymphatic metastasis, and vascular invasion. KIF4A might be involved in promoting the development of PDAC in vitro and in vivo, which might be a new therapeutic target of PDAC.


2021 ◽  
Author(s):  
Hao Yu ◽  
Xiaoping Mei ◽  
Xueming Zhang ◽  
Neng Qian ◽  
Qingjiang Yu ◽  
...  

Abstract Objective: Pancreatic ductal adenocarcinoma (PDAC) serves as a prevailing tumor type with high mortality and poor prognosis. The study aims to explore the mechanism of gemcitabine resistance in PDAC patients. Methods: Immunohistochemistry(IHC)was used to analyze the expression of SLC39A1 in PDAC samples. PDAC cells were culture and transfected with siSLC39A1 and siNC, respectively. Cell proliferation analysis was performed using CCK-8 assay. And qPCR and Western blotting was used to analysis the expression level of SLC39A1 and related signal molecular in cells. Results: IHC results demonstrated that the SLC39A1 expression was significantly up-regulated in the gemcitabine-resistant PDAC samples compared with gemcitabine-sensitive PDAC samples. The treatment of gemcitabine dose-dependently inhibited the viability of the PDAC cells. Meanwhile, the mRNA and protein expression of SLC39A1 were elevated in the gemcitabine-resistant PDAC. The treatment of gemcitabine remarkably decreased viability of PDACs, in which SLC39A1 depletion could reverse this effect. SLC39A1 knockdown could reverse the gemcitabine-induced phosphorylation of AMPK enhanced and gemcitabine-inhibited S6K expression. Conclusion: SLC39A1 contributed to gemcitabine resistance of PDAC by activating AMPK signaling.


Genes ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 766 ◽  
Author(s):  
Yao-Yu Hsieh ◽  
Tsang-Pai Liu ◽  
Chia-Jung Chou ◽  
Hsin-Yi Chen ◽  
Kuen-Haur Lee ◽  
...  

Pancreatic ductal adenocarcinoma (PDAC) is the most common and aggressive type of pancreatic cancer. The five-year survival rate of PDAC is very low (less than 8%), which is associated with the late diagnosis, high metastatic potential, and resistance to therapeutic agents. The identification of better prognostic or therapeutic biomarker may have clinical benefits for PDAC treatment. SMAD4, a central mediator of transforming growth factor beta (TGFβ) signaling pathway, is considered a tumor suppressor gene. SMAD4 inactivation is frequently found in PDAC. However, its role in prognosis and therapeutics of PDAC is still unclear. In this study, we applied bioinformatics approaches, and integrated publicly available resources, to investigate the role of SMAD4 gene deletion in PDAC. We found that SMAD4 deletion was associated with poorer disease-free, but not overall, survival in PDAC patients. Cancer hallmark enrichment and pathway analysis suggested that the upregulation of cell cycle-related genes in SMAD4-deleted PDAC. Chemotherapy response profiling of PDAC cell lines and patient-derived organoids revealed that SMAD4-deleted PDAC was sensitive to gemcitabine, the first-line treatment for PDAC, and specific cell cycle-targeting drugs. Taken together, our study provides an insight into the prognostic and therapeutic roles of SMAD4 gene deletion in PDAC, and SMAD4 gene copy numbers may be used as a therapeutic biomarker for PDAC treatment.


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