1
|
Kathad U, Kulkarni A, McDermott JR, Wegner J, Carr P, Biyani N, Modali R, Richard JP, Sharma P, Bhatia K. A machine learning-based gene signature of response to the novel alkylating agent LP-184 distinguishes its potential tumor indications. BMC Bioinformatics 2021; 22:102. [PMID: 33653269 PMCID: PMC7923321 DOI: 10.1186/s12859-021-04040-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 02/15/2021] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Non-targeted cytotoxics with anticancer activity are often developed through preclinical stages using response criteria observed in cell lines and xenografts. A panel of the NCI-60 cell lines is frequently the first line to define tumor types that are optimally responsive. Open data on the gene expression of the NCI-60 cell lines, provides a unique opportunity to add another dimension to the preclinical development of such drugs by interrogating correlations with gene expression patterns. Machine learning can be used to reduce the complexity of whole genome gene expression patterns to derive manageable signatures of response. Application of machine learning in early phases of preclinical development is likely to allow a better positioning and ultimate clinical success of molecules. LP-184 is a highly potent novel alkylating agent where the preclinical development is being guided by a dedicated machine learning-derived response signature. We show the feasibility and the accuracy of such a signature of response by accurately predicting the response to LP-184 validated using wet lab derived IC50s on a panel of cell lines. RESULTS We applied our proprietary RADR® platform to an NCI-60 discovery dataset encompassing LP-184 IC50s and publicly available gene expression data. We used multiple feature selection layers followed by the XGBoost regression model and reduced the complexity of 20,000 gene expression values to generate a 16-gene signature leading to the identification of a set of predictive candidate biomarkers which form an LP-184 response gene signature. We further validated this signature and predicted response to an additional panel of cell lines. Considering fold change differences and correlation between actual and predicted LP-184 IC50 values as validation performance measures, we obtained 86% accuracy at four-fold cut-off, and a strong (r = 0.70) and significant (p value 1.36e-06) correlation between actual and predicted LP-184 sensitivity. In agreement with the perceived mechanism of action of LP-184, PTGR1 emerged as the top weighted gene. CONCLUSION Integration of a machine learning-derived signature of response with in vitro assessment of LP-184 efficacy facilitated the derivation of manageable yet robust biomarkers which can be used to predict drug sensitivity with high accuracy and clinical value.
Collapse
Affiliation(s)
- Umesh Kathad
- Lantern Pharma, Inc., 1920 McKinney Ave, 7th floor, Dallas, TX, 75201, USA.
| | - Aditya Kulkarni
- Lantern Pharma, Inc., 1920 McKinney Ave, 7th floor, Dallas, TX, 75201, USA
| | | | - Jordan Wegner
- Lantern Pharma, Inc., 1920 McKinney Ave, 7th floor, Dallas, TX, 75201, USA
| | - Peter Carr
- Lantern Pharma, Inc., 1920 McKinney Ave, 7th floor, Dallas, TX, 75201, USA
| | - Neha Biyani
- Lantern Pharma, Inc., 1920 McKinney Ave, 7th floor, Dallas, TX, 75201, USA
| | - Rama Modali
- REPROCELL USA Inc., 9000 Virginia Manor Rd, Ste 207, Beltsville, MD, 20705, USA
| | | | - Panna Sharma
- Lantern Pharma, Inc., 1920 McKinney Ave, 7th floor, Dallas, TX, 75201, USA
| | - Kishor Bhatia
- Lantern Pharma, Inc., 1920 McKinney Ave, 7th floor, Dallas, TX, 75201, USA
| |
Collapse
|
2
|
Peng S, Chen N, Zhang H, He M, Li H, Lang M, Wang J. Palladium(II)-Catalyzed Oxidative Decarboxylative [2 + 2 + 1] Annulation of Cinnamic Acids with Alkynes: Access to Polysubstituted Pentafulvenes. Org Lett 2020; 22:5589-5593. [PMID: 32588631 DOI: 10.1021/acs.orglett.0c01955] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An unprecedented palladium(II)-catalyzed oxidative decarboxylative [2 + 2 + 1] annulation of cinnamic acids with alkynes has been developed for the synthesis of polysubstituted pentafulvenes. Ag2CO3 and DMSO are essential for the reaction. This protocol features readily available starting materials, a wide substrate scope, and moderate to excellent yields. Moreover, various significant frameworks can be easily obtained from the late-stage transformations of pentafulvenes via oxidation, reduction, and Scholl-type reaction.
Collapse
Affiliation(s)
- Shiyong Peng
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China
| | - Nuan Chen
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China
| | - Hong Zhang
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China
| | - Min He
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China
| | - Hongguang Li
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China
| | - Ming Lang
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China
| | - Jian Wang
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China.,School of Pharmaceutical Sciences, Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education), Tsinghua University, Beijing, 100084, P. R. China
| |
Collapse
|
3
|
Phukon J, Gogoi S. Palladium(ii)-catalyzed vinylic geminal double C-H activation and alkyne annulation reaction: synthesis of pentafulvenes. Chem Commun (Camb) 2020; 56:1133-1136. [PMID: 31894770 DOI: 10.1039/c9cc09564k] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first transition-metal-catalyzed vinylic geminal double C(sp2)-H activation and di-substituted alkyne annulation reaction is reported. This palladium(ii)-catalyzed, amide directed reaction of vinylic compounds with di-substituted alkynes offers an efficient synthetic path to pentafulvenes, which are very important compounds because of their bioactivity and interesting optical properties. A FeCl3-mediated transformation of pentafulvenes to fluorescent cyclopenta[b]quinolines is also developed.
Collapse
Affiliation(s)
- Jyotshna Phukon
- Applied Organic Chemistry, Chemical Sciences & Technology Division, CSIR-North East Institute of Science and Technology, AcSIR, Jorhat-785006, India.
| | - Sanjib Gogoi
- Applied Organic Chemistry, Chemical Sciences & Technology Division, CSIR-North East Institute of Science and Technology, AcSIR, Jorhat-785006, India.
| |
Collapse
|
4
|
Suzuki S, Kinoshita H, Miura K. Palladium-Catalyzed Regio- and Stereoselective Synthesis of ( E)-1,3-Bissilyl-6-arylfulvenes from Aryl Iodides and Silylacetylenes. Org Lett 2019; 21:1612-1616. [PMID: 30789738 DOI: 10.1021/acs.orglett.9b00144] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An efficient synthetic route to ( E)-1,3-bissilyl-6-arylfulvenes has been developed. The reaction of aryl iodides with trimethylsilylacetylene in the presence of a catalytic amount of PdBr2 gives 6-aryl-1,3-bis(trimethylsilyl)fulvenes in good to excellent yields with complete regio- and stereoselectivity. The reaction involves trimerization of trimethylsilylacetylene and cleavage of one silyl group. The silylated fulvenes obtained could be converted into halogenated fulvenes by site-selective halodesilylation. The halogenated fulvenes underwent the Stille coupling leading to the corresponding arylated fulvenes.
Collapse
Affiliation(s)
- Souta Suzuki
- Department of Applied Chemistry, Graduate School of Science and Engineering , Saitama University , 255 Shimo-ohkubo , Sakura-ku, Saitama 338-8570 , Japan
| | - Hidenori Kinoshita
- Department of Applied Chemistry, Graduate School of Science and Engineering , Saitama University , 255 Shimo-ohkubo , Sakura-ku, Saitama 338-8570 , Japan
| | - Katsukiyo Miura
- Department of Applied Chemistry, Graduate School of Science and Engineering , Saitama University , 255 Shimo-ohkubo , Sakura-ku, Saitama 338-8570 , Japan
| |
Collapse
|
5
|
Dual inhibition of ATR and ATM potentiates the activity of trabectedin and lurbinectedin by perturbing the DNA damage response and homologous recombination repair. Oncotarget 2017; 7:25885-901. [PMID: 27029031 PMCID: PMC5041952 DOI: 10.18632/oncotarget.8292] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 03/04/2016] [Indexed: 12/27/2022] Open
Abstract
Trabectedin (Yondelis®, ecteinascidin-743, ET-743) is a marine-derived natural product approved for treatment of advanced soft tissue sarcoma and relapsed platinum-sensitive ovarian cancer. Lurbinectedin is a novel anticancer agent structurally related to trabectedin. Both ecteinascidins generate DNA double-strand breaks that are processed through homologous recombination repair (HRR), thereby rendering HRR-deficient cells particularly sensitive. We here characterize the DNA damage response (DDR) to trabectedin and lurbinectedin in HeLa cells. Our results show that both compounds activate the ATM/Chk2 (ataxia-telangiectasia mutated/checkpoint kinase 2) and ATR/Chk1 (ATM and RAD3-related/checkpoint kinase 1) pathways. Interestingly, pharmacological inhibition of Chk1/2, ATR or ATM is not accompanied by any significant improvement of the cytotoxic activity of the ecteinascidins while dual inhibition of ATM and ATR strongly potentiates it. Accordingly, concomitant inhibition of both ATR and ATM is an absolute requirement to efficiently block the formation of γ-H2AX, MDC1, BRCA1 and Rad51 foci following exposure to the ecteinascidins. These results are not restricted to HeLa cells, but are shared by cisplatin-sensitive and -resistant ovarian carcinoma cells. Together, our data identify ATR and ATM as central coordinators of the DDR to ecteinascidins and provide a mechanistic rationale for combining these compounds with ATR and ATM inhibitors.
Collapse
|
6
|
Xiao Z, Morris-Natschke SL, Lee KH. Strategies for the Optimization of Natural Leads to Anticancer Drugs or Drug Candidates. Med Res Rev 2016; 36:32-91. [PMID: 26359649 PMCID: PMC4679534 DOI: 10.1002/med.21377] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Natural products have made significant contribution to cancer chemotherapy over the past decades and remain an indispensable source of molecular and mechanistic diversity for anticancer drug discovery. More often than not, natural products may serve as leads for further drug development rather than as effective anticancer drugs by themselves. Generally, optimization of natural leads into anticancer drugs or drug candidates should not only address drug efficacy, but also improve absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiles and chemical accessibility associated with the natural leads. Optimization strategies involve direct chemical manipulation of functional groups, structure-activity relationship directed optimization and pharmacophore-oriented molecular design based on the natural templates. Both fundamental medicinal chemistry principles (e.g., bioisosterism) and state-of-the-art computer-aided drug design techniques (e.g., structure-based design) can be applied to facilitate optimization efforts. In this review, the strategies to optimize natural leads to anticancer drugs or drug candidates are illustrated with examples and described according to their purposes. Furthermore, successful case studies on lead optimization of bioactive compounds performed in the Natural Products Research Laboratories at UNC are highlighted.
Collapse
Affiliation(s)
- Zhiyan Xiao
- Beijing Key Laboratory of Active Substance Discovery and Druggability Evaluation, Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100050, China
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100050, China
| | - Susan L. Morris-Natschke
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, USA
| | - Kuo-Hsiung Lee
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, USA
- Chinese Medicine Research and Development Center, China Medical University and Hospital, Taichung, Taiwan
| |
Collapse
|
7
|
Yin F, Liu X, Li D, Wang Q, Zhang W, Li L. Tumor suppressor genes associated with drug resistance in ovarian cancer (review). Oncol Rep 2013; 30:3-10. [PMID: 23660957 DOI: 10.3892/or.2013.2446] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 03/29/2013] [Indexed: 11/06/2022] Open
Abstract
Ovarian cancer is a fatal gynecological cancer and a major cause of cancer-related mortality worldwide. The main limitation to a successful treatment for ovarian cancer is the development of drug resistance to combined chemotherapy. Tumor suppressor genes (TSGs) are wild-type alleles of genes which play regulatory roles in diverse cellular activities, and whose loss of function contributes to the development of cancer. It has been demonstrated that TSGs contribute to drug resistance in several types of solid tumors. However, an overview of the contribution of TSGs to drug resistance in ovarian cancer has not previously been reported. In this study, 15 TSGs responding to drug resistance in ovarian cancer were reviewed to determine the relationship of TSGs with ovarian cancer drug resistance. Furthermore, gene/protein-interaction and bio-association analysis were performed to demonstrate the associations of these TSGs and to mine the potential drug resistance-related genes in ovarian cancer. We observed that the 15 TSGs had close interactions with each other, suggesting that they may contribute to drug resistance in ovarian cancer as a group. Five pathways/processes consisting of DNA damage, apoptosis, cell cycle, DNA binding and methylation may be the key ways with which TSGs participate in the regulation of drug resistance. In addition, ubiquitin C (UBC) and six additional TSGs including the adenomatous polyposis coli gene (APC), death associated protein kinase gene (DAPK), pleiomorphic adenoma gene-like 1 (PLAGL1), retinoblastoma susceptibility gene (RB1), a gene encoding an apoptosis-associated speck-like protein (PYCARD/ASC) and tumor protein 63 (TP63), which had close interactions with the 15 TSGs, are potential drug resistance-related genes in ovarian cancer.
Collapse
Affiliation(s)
- Fuqiang Yin
- Department of Gynecologic Oncology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | | | | | | | | | | |
Collapse
|
8
|
Mishra BB, Tiwari VK. Natural products: An evolving role in future drug discovery. Eur J Med Chem 2011; 46:4769-807. [DOI: 10.1016/j.ejmech.2011.07.057] [Citation(s) in RCA: 565] [Impact Index Per Article: 43.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 07/29/2011] [Accepted: 07/30/2011] [Indexed: 11/16/2022]
|
9
|
Soares DG, Battistella A, Rocca CJ, Matuo R, Henriques JAP, Larsen AK, Escargueil AE. Ataxia telangiectasia mutated- and Rad3-related kinase drives both the early and the late DNA-damage response to the monofunctional antitumour alkylator S23906. Biochem J 2011; 437:63-73. [PMID: 21470188 DOI: 10.1042/bj20101770] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Numerous anticancer agents and environmental mutagens target DNA. Although all such compounds interfere with the progression of the replication fork and inhibit DNA synthesis, there are marked differences in the DNA-damage response pathways they trigger, and the relative impact of the proximal or the distal signal transducers on cell survival is mainly lesion-specific. Accordingly, checkpoint kinase inhibitors in current clinical development show synergistic activity with some DNA-targeting agents, but not with others. In the present study, we characterize the DNA-damage response to the antitumour acronycine derivative S23906, which forms monofunctional adducts with guanine residues in the minor groove of DNA. S23906 exposure is accompanied by specific recruitment of RPA (replication protein A) at replication sites and rapid Chk1 activation. In contrast, neither MRN (Mre11-Rad50-Nbs1) nor ATM (ataxia-telangiectasia mutated), contributes to the initial response to S23906. Interestingly, genetic attenuation of ATR (ATM- and Ras3-related) activity inhibits not only the early phosphorylation of histone H2AX and Chk1, but also interferes with the late phosphorylation of Chk2. Moreover, loss of ATR function or pharmacological inhibition of the checkpoint kinases by AZD7762 is accompanied by abrogation of the S-phase arrest and increased sensitivity towards S23906. These findings identify ATR as a central co-ordinator of the DNA-damage response to S23906, and provide a mechanistic rationale for combinations of S23906 and similar agents with checkpoint abrogators.
Collapse
Affiliation(s)
- Daniele G Soares
- Laboratory of Cancer Biology and Therapeutics, Centre de Recherche Saint-Antoine, Paris 75571, France
| | | | | | | | | | | | | |
Collapse
|
10
|
Anderson VE, Walton MI, Eve PD, Boxall KJ, Antoni L, Caldwell JJ, Aherne W, Pearl LH, Oliver AW, Collins I, Garrett MD. CCT241533 is a potent and selective inhibitor of CHK2 that potentiates the cytotoxicity of PARP inhibitors. Cancer Res 2011; 71:463-72. [PMID: 21239475 DOI: 10.1158/0008-5472.can-10-1252] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
CHK2 is a checkpoint kinase involved in the ATM-mediated response to double-strand DNA breaks. Its potential as a drug target is still unclear, but inhibitors of CHK2 may increase the efficacy of genotoxic cancer therapies in a p53 mutant background by eliminating one of the checkpoints or DNA repair pathways contributing to cellular resistance. We report here the identification and characterization of a novel CHK2 kinase inhibitor, CCT241533. X-ray crystallography confirmed that CCT241533 bound to CHK2 in the ATP pocket. This compound inhibits CHK2 with an IC(50) of 3 nmol/L and shows minimal cross-reactivity against a panel of kinases at 1 μmol/L. CCT241533 blocked CHK2 activity in human tumor cell lines in response to DNA damage, as shown by inhibition of CHK2 autophosphorylation at S516, band shift mobility changes, and HDMX degradation. CCT241533 did not potentiate the cytotoxicity of a selection of genotoxic agents in several cell lines. However, this compound significantly potentiates the cytotoxicity of two structurally distinct PARP inhibitors. Clear induction of the pS516 CHK2 signal was seen with a PARP inhibitor alone, and this activation was abolished by CCT241533, implying that the potentiation of PARP inhibitor cell killing by CCT241533 was due to inhibition of CHK2. Consequently, our findings imply that CHK2 inhibitors may exert therapeutic activity in combination with PARP inhibitors.
Collapse
Affiliation(s)
- Victoria E Anderson
- Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, Sutton, Surrey, United Kingdom
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Kandala PK, Srivastava SK. Activation of checkpoint kinase 2 by 3,3'-diindolylmethane is required for causing G2/M cell cycle arrest in human ovarian cancer cells. Mol Pharmacol 2010; 78:297-309. [PMID: 20444961 DOI: 10.1124/mol.110.063750] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
We evaluated the effect of 3,3'-diindolylmethane (DIM) in ovarian cancer cells. DIM treatment inhibited the growth of SKOV-3, TOV-21G, and OVCAR-3 ovarian cancer cells in both a dose- and time-dependent manner with effective concentrations ranging from 40 to 100 muM. Growth-inhibitory effects of DIM were mediated by cell cycle arrest in G(2)/M phase in all the three cell lines. G(2)/M arrest was associated with DNA damage as indicated by phosphorylation of H(2)A.X at Ser139 and activation of checkpoint kinase 2 (Chk2) in all the three cell lines. Other G(2)/M regulatory molecules such as Cdc25C, Cdk1, cyclin B1 were down-regulated by DIM. Cycloheximide or Chk2 inhibitor pretreatment abrogated not only activation of Chk2 but also G(2)/M arrest and apoptosis mediated by DIM. To further establish the involvement of Chk2 in DIM-mediated G(2)/M arrest, cells were transfected with dominant-negative Chk2 (DN-Chk2). Blocking Chk2 activation by DN-Chk2 completely protected cells from DIM-mediated G(2)/M arrest. These results were further confirmed in Chk2 knockout DT40 lymphoma cells, in which DIM failed to cause cell cycle arrest. These results clearly indicate the requirement of Chk2 activation to cause G(2)/M arrest by DIM in ovarian cancer cells. Moreover, blocking Chk2 activation also abrogates the apoptosis-inducing effects of DIM. Furthermore, our results show that DIM treatment cause ROS generation. Blocking ROS generation by N-acetyl cysteine protects the cells from DIM-mediated G(2)/M arrest and apoptosis. Our results establish Chk2 as a potent molecular target of DIM in ovarian cancer cells and provide the rationale for further clinical investigation of DIM.
Collapse
Affiliation(s)
- Prabodh K Kandala
- Department of Biomedical Sciences, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA
| | | |
Collapse
|
12
|
Masamha CP, Benbrook DM. Cyclin D1 degradation is sufficient to induce G1 cell cycle arrest despite constitutive expression of cyclin E2 in ovarian cancer cells. Cancer Res 2009; 69:6565-72. [PMID: 19638577 DOI: 10.1158/0008-5472.can-09-0913] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
D- and E-type cyclins mediate G(1)-S phase cell cycle progression through activation of specific cyclin-dependent kinases (cdk) that phosphorylate the retinoblastoma protein (pRb), thereby alleviating repression of E2F-DP transactivation of S-phase genes. Cyclin D1 is often overexpressed in a variety of cancers and is associated with tumorigenesis and metastasis. Loss of cyclin D can cause G(1) arrest in some cells, but in other cellular contexts, the downstream cyclin E protein can substitute for cyclin D and facilitate G(1)-S progression. The objective of this study was to determine if a flexible heteroarotinoid anticancer compound, SHetA2, regulates cell cycle proteins and cell cycle progression in ovarian cancer cells. SHetA2 induced cyclin D1 phosphorylation, ubiquitination, and proteasomal degradation, causing G(1) arrest in ovarian cancer cells despite continued cyclin E2 expression and independently of p53 and glycogen synthase kinase-3beta. Cyclin D1 loss inhibited pRb S780 phosphorylation by cyclin D1-cdk4/6 and released p21 from cyclin D1-cdk4/6-p21 protein complexes to form cyclin E2-cdk2-p21 complexes, which repressed phosphorylation of pRb S612 by cyclin E2-cdk2 and ultimately E2F-DP transcriptional activity. G(1) arrest was prevented by overexpression or preventing degradation of cyclin D1 but not by restoration of pRb S612 phosphorylation through p21 knockdown. In conclusion, we show that loss of cyclin D1 in ovarian cancer cells treated with SHetA2 is sufficient to induce G(1) cell cycle arrest and this strategy is not impeded by the presence of cyclin E2. Therefore, cyclin D1 is a sufficient therapeutic target in ovarian cancer cells.
Collapse
Affiliation(s)
- Chioniso Patience Masamha
- Departments of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, 73104, USA
| | | |
Collapse
|
13
|
Mana-Hox displays anticancer activity against prostate cancer cells through tubulin depolymerization and DNA damage stress. Naunyn Schmiedebergs Arch Pharmacol 2008; 378:599-608. [PMID: 18663430 DOI: 10.1007/s00210-008-0330-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2008] [Accepted: 06/25/2008] [Indexed: 12/15/2022]
Abstract
Tubulin and deoxyribonucleic acid (DNA) are two potential targets for the development of cancer chemotherapeutic agents. Mana-Hox is a synthetic derivative of beta-carboline, a structure relevant to marine sponge component, manzamine. In this study, Mana-Hox induced an inhibition of cell proliferation in several types of human cancer cell lines, including androgen-independent prostate cancer PC-3 and DU-145, hepatocellular carcinoma Hep3B and HepG2, and colorectal cancer HT-29 cells. The p53-null PC-3 cells were used for to anticancer mechanisms. Mana-Hox stimulated an increase of ataxia telangiectasia mutated (ATM) phosphorylation on Ser-1981, indicating the induction of DNA double-strand breaks. It also displayed an inhibitory effect on tubulin polymerization using tubulin turbidity assay and immunofluorescence identification. However, it only showed a minor inhibition on the activity of Aurora kinase and histone deacetylase. Mana-Hox induced mitotic arrest of the cell cycle identified by downregulation of cyclin E, cyclin A, and cyclin-dependent kinase 2 (Cdk2) and an increase of MPM-2 expression. Next, it caused Bcl-2 phosphorylation on Ser-70, downregulation of Mcl-1 expression, and activation of caspase-3, leading to apoptotic cell death. Notably, Mana-Hox was not a P-glycoprotein (P-gp) substrate and showed equipotent activity against P-gp-rich cancer cells. We conclude that Mana-Hox induces dual effects on DNA damage and tubulin depolymerization, leading to mitotic arrest and activation of mitochondria-mediated apoptotic pathways. Data provide evidence that the anticancer strategy of dual-action targets could be a potential anticancer approach.
Collapse
|
14
|
Butler MS. Natural products to drugs: natural product-derived compounds in clinical trials. Nat Prod Rep 2008; 25:475-516. [PMID: 18497896 DOI: 10.1039/b514294f] [Citation(s) in RCA: 502] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Natural product and natural product-derived compounds that are being evaluated in clinical trials or are in registration (as at 31st December 2007) have been reviewed, as well as natural product-derived compounds for which clinical trials have been halted or discontinued since 2005. Also discussed are natural product-derived drugs launched since 2005, new natural product templates and late-stage development candidates.
Collapse
Affiliation(s)
- Mark S Butler
- MerLion Pharmaceuticals, 1 Science Park Road, The Capricorn 05-01, Singapore Science Park II, Singapore 117528.
| |
Collapse
|
15
|
Kelner MJ, McMorris TC, Rojas RJ, Estes LA, Suthipinijtham P. Synergy of Irofulven in combination with various anti-metabolites, enzyme inhibitors, and miscellaneous agents in MV522 lung carcinoma cells: marked interaction with gemcitabine and 5-fluorouracil. Invest New Drugs 2008; 26:407-15. [PMID: 18227973 DOI: 10.1007/s10637-008-9113-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Accepted: 01/09/2008] [Indexed: 11/24/2022]
Abstract
The novel agent Irofulven (HMAF, NSC 683863) has demonstrated significant antitumor activity against solid tumors in various xenograft models and human clinical trials. The antitumor potential of combining irofulven with 72 different anti-metabolite, enzyme inhibiting, and miscellaneous agents was investigated in this study. The human lung carcinoma MV522 cell line and its corresponding xenograft model were used to evaluate the activity of irofulven in combination with these different agents. Irofulven in combination with select anti-metabolites, notably cytidine or adenine-derived agents, displayed strong synergistic activity in both in vitro and in vivo studies. Agents demonstrating strong synergistic interaction with irofulven included gemcitabine, cyclocytidine, cytarabine, fludarabine phosphate, cladribine, and 5-fluorouracil. Other anti-metabolites, enzyme inhibitors, and a variety of miscellaneous agents failed to interact beneficially when administered in combination with irofulven. The therapeutic activity of irofulven is enhanced considerably when irofulven is combined with select anti-metabolite agents, and further clinical evaluation of these combinations is warranted. The synergistic interaction with these combinations may stem from a variety of actions including inhibition of the nucleotide excision repair (NER) pathway, topoisomerase I activity, and caspase-dependent and independent induction of apoptosis.
Collapse
Affiliation(s)
- Michael J Kelner
- Department of Pathology, University of California, San Diego, USA.
| | | | | | | | | |
Collapse
|