scholarly journals Influence of YES1 Kinase and Tyrosine Phosphorylation on the Activity of OCT1

2021 ◽  
Vol 12 ◽  
Author(s):  
Muhammad Erfan Uddin ◽  
Dominique A. Garrison ◽  
Kyeongmin Kim ◽  
Yan Jin ◽  
Eric D. Eisenmann ◽  
...  

Organic cation transporter 1 (OCT1) is a transporter that regulates the hepatic uptake and subsequent elimination of diverse cationic compounds. Although OCT1 has been involved in drug-drug interactions and causes pharmacokinetic variability of many prescription drugs, details of the molecular mechanisms that regulate the activity of OCT1 remain incompletely understood. Based on an unbiased phospho-proteomics screen, we identified OCT1 as a tyrosine-phosphorylated transporter, and functional validation studies using genetic and pharmacological approaches revealed that OCT1 is highly sensitive to small molecules that target the protein kinase YES1, such as dasatinib. In addition, we found that dasatinib can inhibit hepatic OCT1 function in mice as evidenced from its ability to modulate levels of isobutyryl L-carnitine, a hepatic OCT1 biomarker identified from a targeted metabolomics analysis. These findings provide novel insight into the post-translational regulation of OCT1 and suggest that caution is warranted with polypharmacy regimes involving the combined use of OCT1 substrates and kinase inhibitors that target YES1.

2001 ◽  
Vol 21 (16) ◽  
pp. 5471-5477 ◽  
Author(s):  
Johan W. Jonker ◽  
Els Wagenaar ◽  
Carla A. A. M. Mol ◽  
Marije Buitelaar ◽  
Hermann Koepsell ◽  
...  

ABSTRACT The polyspecific organic cation transporter 1 (OCT1 [SLC22A1]) mediates facilitated transport of small (hydrophilic) organic cations. OCT1 is localized at the basolateral membrane of epithelial cells in the liver, kidney, and intestine and could therefore be involved in the elimination of endogenous amines and xenobiotics via these organs. To investigate the pharmacologic and physiologic role of this transport protein, we generated Oct1 knockout (Oct1 −/−) mice.Oct1 −/− mice appeared to be viable, healthy, and fertile and displayed no obvious phenotypic abnormalities. The role of Oct1 in the pharmacology of substrate drugs was studied by comparing the distribution and excretion of the model substrate tetraethylammonium (TEA) after intravenous administration to wild-type and Oct1 −/− mice. InOct1 −/− mice, accumulation of TEA in liver was four to sixfold lower than in wild-type mice, whereas direct intestinal excretion of TEA was reduced about twofold. Excretion of TEA into urine over 1 h was 53% of the dose in wild-type mice, compared to 80% in knockout mice, probably because inOct1 −/− mice less TEA accumulates in the liver and thus more is available for rapid excretion by the kidney. In addition, we found that absence of Oct1 leads to decreased liver accumulation of the anticancer drug metaiodobenzylguanidine and the neurotoxin 1-methyl-4-phenylpyridium. In conclusion, our data show that Oct1 plays an important role in the uptake of organic cations into the liver and in their direct excretion into the lumen of the small intestine.


2020 ◽  
Vol 17 ◽  
Author(s):  
Perumal Subramaniana ◽  
Jaime Jacqueline Jayapalan ◽  
Puteri Shafinaz Abdul-Rahmanb

A proteome is an efficient rendition of a genome, unswervingly controlling various cancer processes. Molecular mechanisms of several cancer processes have been unraveled by proteomic approach. Thus far, numerous tumors of diverse status have been investigated by two-dimensional electrophoresis. Numerous biomarkers have been recognized and precise categorization of apparent lesions has led to the timely detection of various cancers in persons at peril. Currently used pioneering approaches and technologies in proteomics have led to highly sensitive assays of cancer biomarkers and improved the early diagnosis of various cancers. The discovery of novel and definite biomarker signatures further widened our perceptive of the disease and novel potent drugs for efficient and aimed therapeutic outcomes in persistent cancers have emerged. However, a major limitation, even today, of proteomics is resolving and quantifying the proteins of low abundance. Despite the rapid development of proteomic technologies and their applications in cancer management, annulling the shortcomings of present proteomic technologies and development of better methods are still desirable. The main objectives of this review are to discuss the developing aspects, merits and demerits of pharmacoproteomics, redox proteomics, novel approaches and therapies being used for various types of cancer based on proteome studies.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hiroaki Kanzaki ◽  
Tetsuhiro Chiba ◽  
Junjie Ao ◽  
Keisuke Koroki ◽  
Kengo Kanayama ◽  
...  

AbstractFGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19low (n = 105) patients, there were no significant differences between FGF19high (n = 21) and FGF19low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1590
Author(s):  
Kenichi Suda ◽  
Tetsuya Mitsudomi

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) serve as the standard of care for the first-line treatment of patients with lung cancers with EGFR-activating mutations. However, the acquisition of resistance to EGFR TKIs is almost inevitable, with extremely rare exceptions, and drug-tolerant cells (DTCs) that demonstrate reversible drug insensitivity and that survive the early phase of TKI exposure are hypothesized to be an important source of cancer cells that eventually acquire irreversible resistance. Numerous studies on the molecular mechanisms of drug tolerance of EGFR-mutated lung cancers employ lung cancer cell lines as models. Here, we reviewed these studies to generally describe the features, potential origins, and candidate molecular mechanisms of DTCs. The rapid development of an optimal treatment for EGFR-mutated lung cancer will require a better understanding of the underlying molecular mechanisms of the drug insensitivity of DTCs.


2016 ◽  
Vol 68 (9) ◽  
pp. 1160-1169 ◽  
Author(s):  
Azusa Futatsugi ◽  
Yusuke Masuo ◽  
Shiori Kawabata ◽  
Noritaka Nakamichi ◽  
Yukio Kato

2007 ◽  
Vol 25 (26) ◽  
pp. 4127-4136 ◽  
Author(s):  
Roger Stupp ◽  
Monika E. Hegi ◽  
Mark R. Gilbert ◽  
Arnab Chakravarti

Glioma has been considered resistant to chemotherapy and radiation. Recently, concomitant and adjuvant chemoradiotherapy with temozolomide has become the standard treatment for newly diagnosed glioblastoma. Conversely (neo-)adjuvant PCV (procarbazine, lomustine, vincristine) failed to improve survival in the more chemoresponsive tumor entities of anaplastic oligoastrocytoma and oligodendroglioma. Preclinical investigations suggest synergism or additivity of radiotherapy and temozolomide in glioma cell lines. Although the relative contribution of the concomitant and the adjuvant chemotherapy, respectively, cannot be assessed, the early introduction of chemotherapy and the simultaneous administration with radiotherapy appear to be key for the improvement of outcome. Epigenetic inactivation of the DNA repair enzyme methylguanine methyltransferase (MGMT) seems to be the strongest predictive marker for outcome in patients treated with alkylating agent chemotherapy. Patients whose tumors do not have MGMT promoter methylation are less likely to benefit from the addition of temozolomide chemotherapy and require alternative treatment strategies. The predictive value of MGMT gene promoter methylation is being validated in ongoing trials aiming at overcoming this resistance by a dose-dense continuous temozolomide administration or in combination with MGMT inhibitors. Understanding of molecular mechanisms allows for rational targeting of specific pathways of repair, signaling, and angiogenesis. The addition of tyrosine kinase inhibitors vatalanib (PTK787) and vandetinib (ZD6474), the integrin inhibitor cilengitide, the monoclonal antibodies bevacizumab and cetuximab, the mammalian target of rapamycin inhibitors temsirolimus and everolimus, and the protein kinase C inhibitor enzastaurin, among other agents, are in clinical investigation, building on the established chemoradiotherapy regimen for newly diagnosed glioblastoma.


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