Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
Add more filters










Database
Publication year range
1.
J Cell Mol Med ; 28(9): e18329, 2024 May.
Article in English | MEDLINE | ID: mdl-38693863

ABSTRACT

Therapy failure with the tyrosine kinase inhibitor (TKI) sunitinib remains a great challenge in metastatic renal cell carcinoma (mRCC). Growing evidence indicates that the tumour subpopulation can enter a transient, non-mutagenic drug-tolerant state to endure the treatment underlying the minimal residual disease and tumour relapse. Drug tolerance to sunitinib remains largely unexplored in RCC. Here, we show that sunitinib-tolerant 786-O/S and Caki-2/S cells are induced by prolonged drug treatment showing reduced drug sensitivity, enhanced clonogenicity, and DNA synthesis. Sunitinib-tolerance developed via dynamic processes, including (i) engagement of c-MET and AXL pathways, (ii) alteration of stress-induced p38 kinase and pro-survival BCL-2 signalling, (iii) extensive actin remodelling, which was correlated with activation of focal adhesion proteins. Remarkably, the acute drug response in both sensitive and sunitinib-tolerant cell lines led to dramatic fine-tuning of the actin-cytoskeleton and boosted cellular migration and invasion, indicating that the drug-response might depend on cell state transition rather than pre-existing mutations. The drug-tolerant state was transiently acquired, as the cells resumed initial drug sensitivity after >10 passages under drug withdrawal, reinforcing the concept of dynamic regulation and phenotypic heterogeneity. Our study described molecular events contributing to the reversible switch into sunitinib-tolerance, providing possible novel therapeutic opportunities in RCC.


Subject(s)
Carcinoma, Renal Cell , Cell Movement , Drug Resistance, Neoplasm , Kidney Neoplasms , Sunitinib , Humans , Carcinoma, Renal Cell/drug therapy , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/metabolism , Sunitinib/pharmacology , Sunitinib/therapeutic use , Cell Line, Tumor , Kidney Neoplasms/drug therapy , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Kidney Neoplasms/metabolism , Drug Resistance, Neoplasm/genetics , Drug Resistance, Neoplasm/drug effects , Cell Movement/drug effects , Receptor Protein-Tyrosine Kinases/metabolism , Receptor Protein-Tyrosine Kinases/genetics , Signal Transduction/drug effects , Proto-Oncogene Proteins c-met/metabolism , Proto-Oncogene Proteins c-met/genetics , Antineoplastic Agents/pharmacology , Proto-Oncogene Proteins c-bcl-2/metabolism , Proto-Oncogene Proteins c-bcl-2/genetics , Axl Receptor Tyrosine Kinase , Pyrroles/pharmacology , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins/genetics , Cell Proliferation/drug effects , Indoles/pharmacology
2.
Int J Mol Sci ; 24(6)2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36982721

ABSTRACT

The tyrosine kinase inhibitor (TKI) cabozantinib might impede the growth of the sunitinib-resistant cell lines by targeting MET and AXL overexpression in metastatic renal cell carcinoma (mRCC). We studied the role of MET and AXL in the response to cabozantinib, particularly following long-term administration with sunitinib. Two sunitinib-resistant cell lines, 786-O/S and Caki-2/S, and the matching 786-O/WT and Caki-2/WT cells were exposed to cabozantinib. The drug response was cell-line-specific. The 786-O/S cells were less growth-inhibited by cabozantinib than 786-O/WT cells (p-value = 0.02). In 786-O/S cells, the high level of phosphorylation of MET and AXL was not affected by cabozantinib. Despite cabozantinib hampering the high constitutive phosphorylation of MET, the Caki-2 cells showed low sensitivity to cabozantinib, and this was independent of sunitinib pretreatment. In both sunitinib-resistant cell lines, cabozantinib increased Src-FAK activation and impeded mTOR expression. The modulation of ERK and AKT was cell-line-specific, mirroring the heterogeneity among the patients. Overall, the MET- and AXL-driven status did not affect cell responsiveness to cabozantinib in the second-line treatment. The activation of Src-FAK might counteract cabozantinib activity and contribute to tumor survival and may be considered an early indicator of therapy response.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Humans , Sunitinib/pharmacology , Sunitinib/therapeutic use , Carcinoma, Renal Cell/drug therapy , Carcinoma, Renal Cell/pathology , Kidney Neoplasms/drug therapy , Kidney Neoplasms/pathology , Anilides/therapeutic use , Cell Line
3.
Aktuelle Urol ; 52(5): 452-463, 2021 09.
Article in German | MEDLINE | ID: mdl-34157774

ABSTRACT

During the last three decades, renal tumours have become increasingly well differentiated on the basis of their histopathological and molecular features. This subtyping has increasingly impacted clinical practice because more therapeutic options are available in organ-confined and metastatic renal cell tumours. The knowledge of the underlying molecular alterations is essential to develop molecular targeted therapies and to select the most effective systemic therapy for each patient. This manuscript gives an overview of the molecular differentiation on the one hand, and on diagnostic, prognostic and predictive biomarkers on the other hand.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Biomarkers , Biomarkers, Tumor , Carcinoma, Renal Cell/diagnosis , Carcinoma, Renal Cell/genetics , Humans , Kidney , Kidney Neoplasms/diagnosis , Kidney Neoplasms/genetics , Molecular Targeted Therapy , Prognosis
4.
BMC Cancer ; 20(1): 264, 2020 Mar 30.
Article in English | MEDLINE | ID: mdl-32228510

ABSTRACT

BACKGROUND: The human pancreatic cancer cell line A818-6 can be grown in vitro either as a highly malignant, undifferentiated monolayer (ML) or as three-dimensional (3D) single layer hollow spheres (HS) simulating a benign, highly differentiated, duct-like pancreatic epithelial structure. This characteristic allowing A818-6 cells to switch from one phenotype to another makes these cells a unique system to characterize the cellular and molecular modifications during differentiation on one hand and malignant transformation on the other hand. Ion channels and transport proteins (transportome) have been implicated in malignant transformation. Therefore, the current study aimed to analyse the transportome gene expression profile in the A818-6 cells growing as a monolayer or as hollow spheres. METHODS & RESULTS: The study identified the differentially expressed transportome genes in both cellular states of A818-6 using Agilent and Nanostring arrays and some targets were validated via immunoblotting. Additionally, these results were compared to a tissue Affymetrix microarray analysis of pancreatic adenocarcinoma patients' tissues. The overall transcriptional profile of the ML and HS cells confirmed the formerly described mesenchymal features of ML and epithelial nature of HS which was further verified via high expression of E-cadherin and low expression of vimentin found in HS in comparison to ML. Among the predicted features between HS and ML was the involvement of miRNA-9 in this switch. Importantly, the bioinformatics analysis also revealed substantial number (n = 126) of altered transportome genes. Interestingly, three genes upregulated in PDAC tissue samples (GJB2, GJB5 and SLC38A6) were found to be also upregulated in ML and 3 down-regulated transportome genes (KCNQ1, TRPV6 and SLC4A) were also reduced in ML. CONCLUSION: This reversible HS/ML in vitro system might help in understanding the pathophysiological impact of the transportome in the dedifferentiation process in pancreatic carcinogenesis. Furthermore, the HS/ML model represents a novel system for studying the role of the transportome during the switch from a more benign, differentiated (HS) to a highly malignant, undifferentiated (ML) phenotype.


Subject(s)
Adenocarcinoma/metabolism , Pancreatic Neoplasms/metabolism , Transcriptome/genetics , Adenocarcinoma/pathology , Amino Acid Transport Systems, Neutral/genetics , Amino Acid Transport Systems, Neutral/metabolism , Cadherins/genetics , Cadherins/metabolism , Carcinogenesis/genetics , Cell Differentiation/genetics , Cell Line, Tumor , Cell Plasticity , Computational Biology , Connexin 26 , Connexins/genetics , Connexins/metabolism , Gene Expression Regulation, Neoplastic , Humans , MicroRNAs/genetics , Pancreatic Neoplasms/pathology
5.
Cancer Cell ; 31(4): 516-531.e10, 2017 04 10.
Article in English | MEDLINE | ID: mdl-28399409

ABSTRACT

The potassium channel Kv1.3 is highly expressed in the mitochondria of various cancerous cells. Here we show that direct inhibition of Kv1.3 using two mitochondria-targeted inhibitors alters mitochondrial function and leads to reactive oxygen species (ROS)-mediated death of even chemoresistant cells independently of p53 status. These inhibitors killed 98% of ex vivo primary chronic B-lymphocytic leukemia tumor cells while sparing healthy B cells. In orthotopic mouse models of melanoma and pancreatic ductal adenocarcinoma, the compounds reduced tumor size by more than 90% and 60%, respectively, while sparing immune and cardiac functions. Our work provides direct evidence that specific pharmacological targeting of a mitochondrial potassium channel can lead to ROS-mediated selective apoptosis of cancer cells in vivo, without causing significant side effects.


Subject(s)
Antineoplastic Agents/pharmacology , Kv1.3 Potassium Channel/antagonists & inhibitors , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Potassium Channel Blockers/pharmacology , Aged , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/pathology , Case-Control Studies , Coumarins/pharmacology , Drug Stability , Female , Humans , Kv1.3 Potassium Channel/metabolism , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Melanoma/drug therapy , Melanoma/pathology , Mice, Inbred C57BL , Middle Aged , Mitochondria/drug effects , Mitochondria/metabolism , Molecular Targeted Therapy , Organophosphorus Compounds/pharmacology , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/pathology , Potassium Channel Blockers/chemical synthesis , Potassium Channel Blockers/chemistry
6.
Oncotarget ; 8(24): 38276-38293, 2017 Jun 13.
Article in English | MEDLINE | ID: mdl-27542263

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) represents the most common form of pancreatic cancer with rising incidence in developing countries. Unfortunately, the overall 5-year survival rate is still less than 5%. The most frequent oncogenic mutations in PDAC are loss-of function mutations in p53 and gain-of-function mutations in KRAS. Here we show that clofazimine (Lamprene), a drug already used in the clinic for autoimmune diseases and leprosy, is able to efficiently kill in vitro five different PDAC cell lines harboring p53 mutations. We provide evidence that clofazimine induces apoptosis in PDAC cells with an EC50 in the µM range via its specific inhibitory action on the potassium channel Kv1.3. Intraperitoneal injection of clofazimine resulted in its accumulation in the pancreas of mice 8 hours after administration. Using an orthotopic PDAC xenotransplantation model in SCID beige mouse, we show that clofazimine significantly and strongly reduced the primary tumor weight. Thus, our work identifies clofazimine as a promising therapeutic agent against PDAC and further highlights ion channels as possible oncological targets.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Pancreatic Ductal/pathology , Clofazimine/pharmacology , Kv1.3 Potassium Channel/drug effects , Pancreatic Neoplasms/pathology , Animals , Apoptosis/drug effects , Cell Line, Tumor , Humans , Kv1.3 Potassium Channel/antagonists & inhibitors , Mice , Mice, SCID , Xenograft Model Antitumor Assays
7.
Oncotarget ; 8(1): 769-784, 2017 Jan 03.
Article in English | MEDLINE | ID: mdl-27903970

ABSTRACT

Pancreatic stellate cells (PSCs) play a critical role in the progression of pancreatic ductal adenocarcinoma (PDAC). Once activated, PSCs support proliferation and metastasis of carcinoma cells. PSCs even co-metastasise with carcinoma cells. This requires the ability of PSCs to migrate. In recent years, it has been established that almost all "hallmarks of cancer" such as proliferation or migration/invasion also rely on the expression and function of ion channels. So far, there is only very limited information about the function of ion channels in PSCs. Yet, there is growing evidence that ion channels in stromal cells also contribute to tumor progression. Here we investigated the function of KCa3.1 channels in PSCs. KCa3.1 channels are also found in many tumor cells of different origin. We revealed the functional expression of KCa3.1 channels by means of Western blot, immunofluorescence and patch clamp analysis. The impact of KCa3.1 channel activity on PSC function was determined with live-cell imaging and by measuring the intracellular Ca2+ concentration ([Ca2+]i). KCa3.1 channel blockade or knockout prevents the stimulation of PSC migration and chemotaxis by reducing the [Ca2+]i and calpain activity. KCa3.1 channels functionally cooperate with TRPC3 channels that are upregulated in PDAC stroma. Knockdown of TRPC3 channels largely abolishes the impact of KCa3.1 channels on PSC migration. In summary, our results clearly show that ion channels are crucial players in PSC physiology and pathophysiology.


Subject(s)
Ion Channels/genetics , Ion Channels/metabolism , Pancreatic Stellate Cells/metabolism , Animals , Calcium/metabolism , Carcinoma, Pancreatic Ductal , Cell Line, Tumor , Cell Movement/genetics , Chemotaxis/genetics , Gene Expression , Humans , Intermediate-Conductance Calcium-Activated Potassium Channels/genetics , Intermediate-Conductance Calcium-Activated Potassium Channels/metabolism , Mice , Mice, Knockout , Pancreatic Neoplasms , Pancreatic Stellate Cells/drug effects , Platelet-Derived Growth Factor/metabolism , Platelet-Derived Growth Factor/pharmacology , TRPC Cation Channels/genetics , TRPC Cation Channels/metabolism , Pancreatic Neoplasms
8.
Neoplasia ; 17(2): 155-66, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25748234

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers principally because of early invasion and metastasis. The epidermal growth factor receptor (EGFR) is essential for PDAC development even in the presence of Kras, but its inhibition with erlotinib gives only a modest clinical response, making the discovery of novel EGFR targets of critical interest. Here, we revealed by mining a human pancreatic gene expression database that the metastasis promoter Na(+)/H(+) exchanger (NHE1) associates with the EGFR in PDAC. In human PDAC cell lines, we confirmed that NHE1 drives both basal and EGF-stimulated three-dimensional growth and early invasion via invadopodial extracellular matrix digestion. EGF promoted the complexing of EGFR with NHE1 via the scaffolding protein Na+/H+ exchanger regulatory factor 1, engaging EGFR in a negative transregulatory loop that controls the extent and duration of EGFR oncogenic signaling and stimulates NHE1. The specificity of NHE1 for growth or invasion depends on the segregation of the transient EGFR/Na+/H+ exchanger regulatory factor 1/NHE1 signaling complex into dimeric subcomplexes in different lipid raftlike membrane domains. This signaling complex was also found in tumors developed in orthotopic mice. Importantly, the specific NHE1 inhibitor cariporide reduced both three-dimensional growth and invasion independently of PDAC subtype and synergistically sensitized these behaviors to low doses of erlotinib.


Subject(s)
Carcinoma, Pancreatic Ductal/secondary , Cation Transport Proteins/metabolism , ErbB Receptors/metabolism , Pancreatic Neoplasms/pathology , Sodium-Hydrogen Exchangers/metabolism , Animals , Anti-Arrhythmia Agents/therapeutic use , Blotting, Western , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/metabolism , Cell Line , Cell Line, Tumor , Drug Therapy, Combination , Erlotinib Hydrochloride , Guanidines/therapeutic use , Humans , Mice , Mice, Nude , Mice, SCID , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/metabolism , Protein Kinase Inhibitors/therapeutic use , Quinazolines/therapeutic use , Signal Transduction , Sodium-Hydrogen Exchanger 1 , Sulfones/therapeutic use
SELECTION OF CITATIONS
SEARCH DETAIL
...