In vitro and In vivo Pharmacokinetic-Pharmacodynamic Relationships for the Trisubstituted Aminopurine Cyclin-Dependent Kinase Inhibitors Olomoucine, Bohemine and CYC202

Understanding how cyclin-cdk complexes recognize their substrates is a central problem in cell cycle biology. We identified an E2F1-derived eight-residue peptide which blocked the binding of cyclin A and E-cdk2 complexes to E2F1 and p21. Short peptides spanning similar sequences in p107, p130, and p21-like cdk inhibitors likewise bound to cyclin A-cdk2 and cyclin E-cdk2. In addition, these peptides promoted formation of stable cyclin A-cdk2 complexes in vitro but inhibited the phosphorylation of the retinoblastoma protein by cyclin A- but not cyclin B-associated kinases. Mutation of the cyclin-cdk2 binding motifs in p107 and E2F1 likewise prevented their phosphorylation by cyclin A-associated kinases in vitro. The cdk inhibitor p21 was found to contain two functional copies of this recognition motif, as determined by in vitro kinase binding/inhibition assays and in vivo growth suppression assays. Thus, these studies have identified a cyclin A- and E-cdk2 substrate recognition motif. Furthermore, these data suggest that p21-like cdk inhibitors function, at least in part, by blocking the interaction of substrates with cyclin-cdk2 complexes.

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Cyclin-dependent Kinases Participate in Death of Neurons Evoked by DNA-damaging Agents

The Journal of Cell Biology ◽

10.1083/jcb.143.2.457 ◽

1998 ◽

Vol 143 (2) ◽

pp. 457-467 ◽

Cited By ~ 167

Author(s):

David S. Park ◽

Erick J. Morris ◽

Jaya Padmanabhan ◽

Michael L. Shelanski ◽

Herbert M. Geller ◽

...

Keyword(s):

Cortical Neurons ◽

Sindbis Virus ◽

Kinase Inhibitors ◽

Sympathetic Neurons ◽

Dominant Negative ◽

Cyclin Dependent Kinase ◽

Cyclin Dependent Kinases ◽

Dna Damaging Agents

Previous reports have indicated that DNA-damaging treatments including certain anticancer therapeutics cause death of postmitotic nerve cells both in vitro and in vivo. Accordingly, it has become important to understand the signaling events that control this process. We recently hypothesized that certain cell cycle molecules may play an important role in neuronal death signaling evoked by DNA damage. Consequently, we examined whether cyclin-dependent kinase inhibitors (CKIs) and dominant-negative (DN) cyclin-dependent kinases (CDK) protect sympathetic and cortical neurons against DNA-damaging conditions. We show that Sindbis virus–induced expression of CKIs p16ink4, p21waf/cip1, and p27kip1, as well as DN-Cdk4 and 6, but not DN-Cdk2 or 3, protect sympathetic neurons against UV irradiation– and AraC-induced death. We also demonstrate that the CKIs p16 and p27 as well as DN-Cdk4 and 6 but not DN-Cdk2 or 3 protect cortical neurons from the DNA damaging agent camptothecin. Finally, in consonance with our hypothesis and these results, cyclin D1–associated kinase activity is rapidly and highly elevated in cortical neurons upon camptothecin treatment. These results suggest that postmitotic neurons may utilize Cdk4 and 6, signals that normally control proliferation, to mediate death signaling resulting from DNA-damaging conditions.

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Evidence of oncogene-induced senescence in thyroid carcinogenesis

Endocrine Related Cancer ◽

10.1530/erc-11-0240 ◽

2011 ◽

Vol 18 (6) ◽

pp. 743-757 ◽

Cited By ~ 29

Author(s):

Maria Grazia Vizioli ◽

Patricia A Possik ◽

Eva Tarantino ◽

Katrin Meissl ◽

Maria Grazia Borrello ◽

...

Keyword(s):

Kinase Inhibitors ◽

Tumour Progression ◽

Growth Arrest ◽

Immunohistochemical Analysis ◽

Cyclin Dependent Kinase ◽

Thyroid Tumour ◽

Thyroid Epithelium

Oncogene-induced senescence (OIS) is a growth arrest triggered by the enforced expression of cancer-promoting genes and acts as a barrier against malignant transformation in vivo. In this study, by a combination of in vitro and in vivo approaches, we investigate the role of OIS in tumours originating from the thyroid epithelium. We found that expression of different thyroid tumour-associated oncogenes in primary human thyrocytes triggers senescence, as demonstrated by the presence of OIS hallmarks: changes in cell morphology, accumulation of SA-β-Gal and senescence-associated heterochromatic foci, and upregulation of transcription of the cyclin-dependent kinase inhibitors p16INK4a and p21CIP1. Furthermore, immunohistochemical analysis of a panel of thyroid tumours characterised by different aggressiveness showed that the expression of OIS markers such as p16INK4a, p21CIP1 and IGFBP7 is upregulated at early stages, and lost during thyroid tumour progression. Taken together, our results suggest a role of OIS in thyroid carcinogenesis.

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Implementing Patient-Derived Xenografts to Assess the Effectiveness of Cyclin-Dependent Kinase Inhibitors in Glioblastoma

Cancers ◽

10.3390/cancers11122005 ◽

2019 ◽

Vol 11 (12) ◽

pp. 2005 ◽

Cited By ~ 2

Author(s):

Janis J. Noonan ◽

Monika Jarzabek ◽

Frank A. Lincoln ◽

Brenton L. Cavanagh ◽

Arhona R. Pariag ◽

...

Keyword(s):

Kinase Inhibitors ◽

Death Receptor ◽

Primary Brain Tumor ◽

Cdk Inhibitor ◽

Death Receptor 5 ◽

Cyclin Dependent Kinase ◽

Human Gbm ◽

Pdx Models

Glioblastoma (GBM) is the most common primary brain tumor with no available cure. As previously described, seliciclib, a first-generation cyclin-dependent kinase (CDK) inhibitor, down-regulates the anti-apoptotic protein, Mcl-1, in GBM, thereby sensitizing GBM cells to the apoptosis-inducing effects of the death receptor ligand, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Here, we have assessed the efficacy of seliciclib when delivered in combination with the antibody against human death receptor 5, drozitumab, in clinically relevant patient-derived xenograft (PDX) models of GBM. A reduction in viability and significant levels of apoptosis were observed in vitro in human GBM neurospheres following treatment with seliciclib plus drozitumab. While the co-treatment strategy induced a similar effect in PDX models, the dosing regimen required to observe seliciclib-targeted responses in the brain, resulted in lethal toxicity in 45% of animals. Additional studies showed that the second-generation CDK inhibitor, CYC065, with improved potency in comparison to seliciclib, induced a significant decrease in the size of human GBM neurospheres in vitro and was well tolerated in vivo, upon administration at clinically relevant doses. This study highlights the continued need for robust pre-clinical assessment of promising treatment approaches using clinically relevant models.

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Approach in improving potency and selectivity of kinase inhibitors: Allosteric kinase inhibitors

Mini-Reviews in Medicinal Chemistry ◽

10.2174/1389557521666201222144355 ◽

2020 ◽

Vol 21 ◽

Author(s):

Shangfei Wei ◽

Tianming Zhao ◽

Jie Wang ◽

Xin Zhai

Keyword(s):

Protein Interactions ◽

Kinase Inhibitors ◽

Binding Modes ◽

Allosteric Inhibitors ◽

Wide Range ◽

Allosteric Sites ◽

Protein Functions ◽

Regulate Protein

: Allostery is an efficient and particular regulatory mechanism to regulate protein functions. Different from conserved orthosteric sites, allosteric sites have distinctive functional mechanism to form the complex regulatory network. In drug discovery, kinase inhibitors targeting the allosteric pockets have received extensive attention for the advantages of high selectivity and low toxicity. The approval of trametinib as the first allosteric inhibitor validated that allosteric inhibitors could be used as effective therapeutic drugs for treatment of diseases. To date, a wide range of allosteric inhibitors have been identified. In this perspective, we outline different binding modes and potential advantages of allosteric inhibitors. In the meantime, the research processes of typical and novel allosteric inhibitors are described briefly in terms of structureactivity relationships, ligand-protein interactions and in vitro and in vivo activity. Additionally, challenges as well as opportunities are presented.

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Alkaloids as Anticancer Agents: A Review of Chinese Patents in Recent 5 Years

Recent Patents on Anti-Cancer Drug Discovery ◽

10.2174/1574892815666200131120618 ◽

2020 ◽

Vol 15 (1) ◽

pp. 2-13 ◽

Cited By ~ 3

Author(s):

Hongyu Tao ◽

Ling Zuo ◽

Huanli Xu ◽

Cong Li ◽

Gan Qiao ◽

...

Keyword(s):

Anticancer Activity ◽

Anticancer Agents ◽

Kinase Inhibitors ◽

Protein Kinase Inhibitors ◽

Cdk Inhibitors ◽

Comprehensive Overview ◽

P53 Expression ◽

Study Results

Background: In recent years, many novel alkaloids with anticancer activity have been found in China, and some of them are promising for developing as anticancer agents. Objective: This review aims to provide a comprehensive overview of the information about alkaloid anticancer agents disclosed in Chinese patents, and discusses their potential to be developed as anticancer drugs used clinically. Methods: Anticancer alkaloids disclosed in Chinese patents in recent 5 years were presented according to their mode of actions. Their study results published on PubMed, and SciDirect databases were presented. Results: More than one hundred anticancer alkaloids were disclosed in Chinese patents and their mode of action referred to arresting cell cycle, inhibiting protein kinases, affecting DNA synthesis and p53 expression, etc. Conclusion: Many newly found alkaloids displayed potent anticancer activity both in vitro and in vivo, and some of the anticancer alkaloids acted as protein kinase inhibitors or CDK inhibitors possess the potential for developing as novel anticancer agents.

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The impact of FGF19/FGFR4 signaling inhibition in antitumor activity of multi-kinase inhibitors in hepatocellular carcinoma

Scientific Reports ◽

10.1038/s41598-021-84117-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hiroaki Kanzaki ◽

Tetsuhiro Chiba ◽

Junjie Ao ◽

Keisuke Koroki ◽

Kengo Kanayama ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Molecular Mechanisms ◽

Kinase Inhibitors ◽

Progression Free Survival ◽

Erk Signaling ◽

Enzyme Linked Immunosorbent Assay ◽

Antitumor Effects ◽

The Impact

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.

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The Individual Effects of Cyclin-Dependent Kinase Inhibitors on Head and Neck Cancer Cells—A Systematic Analysis

Cancers ◽

10.3390/cancers13102396 ◽

2021 ◽

Vol 13 (10) ◽

pp. 2396

Author(s):

Nina Schoenwaelder ◽

Inken Salewski ◽

Nadja Engel ◽

Mareike Krause ◽

Björn Schneider ◽

...

Keyword(s):

Combination Therapy ◽

Head And Neck ◽

Kinase Inhibitors ◽

In Vivo Studies ◽

Specific Response ◽

Cyclin Dependent Kinase ◽

Systematic Analysis ◽

Mhc I ◽

Oncological Treatment

Cyclin-dependent kinase inhibitors (CDKi´s) display cytotoxic activity against different malignancies, including head and neck squamous cell carcinomas (HNSCC). By coordinating the DNA damage response, these substances may be combined with cytostatics to enhance cytotoxicity. Here, we investigated the influence of different CDKi´s (palbociclib, dinaciclib, THZ1) on two HNSCC cell lines in monotherapy and combination therapy with clinically-approved drugs (5-FU, Cisplatin, cetuximab). Apoptosis/necrosis, cell cycle, invasiveness, senescence, radiation-induced γ-H2AX DNA double-strand breaks, and effects on the actin filament were studied. Furthermore, the potential to increase tumor immunogenicity was assessed by analyzing Calreticulin translocation and immune relevant surface markers. Finally, an in vivo mouse model was used to analyze the effect of dinaciclib and Cisplatin combination therapy. Dinaciclib, palbociclib, and THZ1 displayed anti-neoplastic activity after low-dose treatment, while the two latter substances slightly enhanced radiosensitivity. Dinaciclib decelerated wound healing, decreased invasiveness, and induced MHC-I, accompanied by high amounts of surface-bound Calreticulin. Numbers of early and late apoptotic cells increased initially (24 h), while necrosis dominated afterward. Antitumoral effects of the selective CDKi palbociclib were weaker, but combinations with 5-FU potentiated effects of the monotherapy. Additionally, CDKi and CDKi/chemotherapy combinations induced MHC I, indicative of enhanced immunogenicity. The in vivo studies revealed a cell line-specific response with best tumor growth control in the combination approach. Global acting CDKi’s should be further investigated as targeting agents for HNSCC, either individually or in combination with selected drugs. The ability of dinaciclib to increase the immunogenicity of tumor cells renders this substance a particularly interesting candidate for immune-based oncological treatment regimens.

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Gilteritinib overcomes lorlatinib resistance in ALK-rearranged cancer

Nature Communications ◽

10.1038/s41467-021-21396-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Hayato Mizuta ◽

Koutaroh Okada ◽

Mitsugu Araki ◽

Jun Adachi ◽

Ai Takemoto ◽

...

Keyword(s):

Gene Rearrangement ◽

Kinase Inhibitors ◽

Inhibitory Effect ◽

In Vivo Model ◽

Resistance Mutations ◽

Lung Cancer Patients ◽

Short Period ◽

Tki Resistance

AbstractALK gene rearrangement was observed in 3%–5% of non-small cell lung cancer patients, and multiple ALK-tyrosine kinase inhibitors (TKIs) have been sequentially used. Multiple ALK-TKI resistance mutations have been identified from the patients, and several compound mutations, such as I1171N + F1174I or I1171N + L1198H are resistant to all the approved ALK-TKIs. In this study, we found that gilteritinib has an inhibitory effect on ALK-TKI–resistant single mutants and I1171N compound mutants in vitro and in vivo. Surprisingly, EML4-ALK I1171N + F1174I compound mutant-expressing tumors were not completely shrunk but regrew within a short period of time after alectinib or lorlatinib treatment. However, the relapsed tumor was markedly shrunk after switching to the gilteritinib in vivo model. In addition, gilteritinib was effective against NTRK-rearranged cancers including entrectinib-resistant NTRK1 G667C-mutant and ROS1 fusion-positive cancer.

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Targeting USP47 overcomes tyrosine kinase inhibitor resistance and eradicates leukemia stem/progenitor cells in chronic myelogenous leukemia

Nature Communications ◽

10.1038/s41467-020-20259-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Hu Lei ◽

Han-Zhang Xu ◽

Hui-Zhuang Shan ◽

Meng Liu ◽

Ying Lu ◽

...

Keyword(s):

Tyrosine Kinase ◽

Progenitor Cells ◽

Chronic Myelogenous Leukemia ◽

Drug Targets ◽

Kinase Inhibitors ◽

Kinase Inhibitor ◽

Myelogenous Leukemia ◽

Tki Resistance

AbstractIdentifying novel drug targets to overcome resistance to tyrosine kinase inhibitors (TKIs) and eradicating leukemia stem/progenitor cells are required for the treatment of chronic myelogenous leukemia (CML). Here, we show that ubiquitin-specific peptidase 47 (USP47) is a potential target to overcome TKI resistance. Functional analysis shows that USP47 knockdown represses proliferation of CML cells sensitive or resistant to imatinib in vitro and in vivo. The knockout of Usp47 significantly inhibits BCR-ABL and BCR-ABLT315I-induced CML in mice with the reduction of Lin−Sca1+c-Kit+ CML stem/progenitor cells. Mechanistic studies show that stabilizing Y-box binding protein 1 contributes to USP47-mediated DNA damage repair in CML cells. Inhibiting USP47 by P22077 exerts cytotoxicity to CML cells with or without TKI resistance in vitro and in vivo. Moreover, P22077 eliminates leukemia stem/progenitor cells in CML mice. Together, targeting USP47 is a promising strategy to overcome TKI resistance and eradicate leukemia stem/progenitor cells in CML.

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