bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Herbal Compound Farnesiferol C Exerts Antiangiogenic and Antitumor Activity and Targets Multiple Aspects of VEGFR1 (Flt1) or VEGFR2 (Flk1) Signaling Cascades
Authors: Lee Jae-Ho , Choi Sun , Lee Yoonji , Lee Hyo-Jeong , Kim Kwan-Hyun , Ahn Kyoo-Seok , Bae Hyunsoo , Lee Hyo-Jung , Lee Eun-Ok , Ahn Kwang-Seok , Ryu Shi Yong , Lü Junxuan , Kim Sung-Hoon
Published: April 2023

Abstract
Farnesiferol C (FC) is one of the major compounds isolated from Ferula assafoetida, an Asian herbal spice used for cancer treatment as a folk remedy. Here, we examined the hypothesis that novel antiangiogenic activities of FC contribute to anticancer efficacy. In human umbilical vein endothelial cells (HUVEC), exposure to the 10 to 40 μmol/L concentration range of FC inhibited vascular endothelial growth factor (VEGF)–induced cell proliferation, migration, invasion, tube formation, and the expression of matrix metalloproteinase-2. In addition, FC inhibited the angiogenic sprouting of VEGF-treated rat aorta in an ex vivo model. Furthermore, FC inhibited the in vivo growth of mouse Lewis lung cancer allograft model by 60% (P < 0.001) at a daily i.p. dosage of 1 mg/kg body weight without any negative effect on the weight of the host mice. Immunohistochemistry staining showed decreased microvessel density (CD34) and proliferative index (Ki-67) without affecting the apoptotic (terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling) index. Mechanistically, FC decreased the binding of VEGF to VEGFR1/Flt-1, but not to VEGFR2/KDR/Flk-1. In terms of early signaling, FC exerted a rapid inhibitory action (examined within 10 minutes) on VEGF-induced autophosphorylation of VEGFR1 without affecting that of VEGFR2. Nevertheless, FC decreased the phosphorylation of most of the kinases downstream of VEGFR2: focal adhesion kinase, Src, extracellular signal-regulated kinase 1/2, p38 mitogen-activated protein kinase, and c-jun-NH2-kinase without affecting AKT. Computer simulation suggests that FC may inhibit Src or focal adhesion kinase protein activities directly through its docking to their ATP-binding sites. Taken together, the multitargeting actions of FC, particularly VEGFR1 inhibition, may make it a novel drug candidate to complement current VEGF/VEGFR2-targeting antiangiogenic modalities for cancer. Mol Cancer Ther; 9(2); 389–99
Data from Identification of c-Src as a Potential Therapeutic Target for Gastric Cancer and of MET Activation as a Cause of Resistance to c-Src Inhibition
Authors: Okamoto Wataru , Okamoto Isamu , Yoshida Takeshi , Okamoto Kunio , Takezawa Ken , Hatashita Erina , Yamada Yuki , Kuwata Kiyoko , Arao Tokuzo , Yanagihara Kazuyoshi , Fukuoka Masahiro , Nishio Kazuto , Nakagawa Kazuhiko
Published: April 2023

Abstract
Therapeutic strategies that target c-Src hold promise for a wide variety of cancers. We have now investigated both the effects of dasatinib, which inhibits the activity of c-Src and several other kinases, on cell growth as well as the mechanism of dasatinib resistance in human gastric cancer cell lines. Immunoblot analysis revealed the activation of c-Src at various levels in most gastric cancer cell lines examined. Dasatinib inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) and induced G1 arrest, as revealed by flow cytometry, in a subset of responsive cell lines. In other responsive cell lines, dasatinib inhibited both ERK and AKT phosphorylation and induced apoptosis, as revealed by an increase in caspase-3 activity and cleavage of poly(ADP-ribose) polymerase. Depletion of c-Src by RNA interference also induced G1 arrest or apoptosis in dasatinib-responsive cell lines, indicating that the antiproliferative effect of dasatinib is attributable to c-Src inhibition. Gastric cancer cell lines positive for the activation of MET were resistant to dasatinib. Dasatinib had no effect on ERK or AKT signaling, whereas the MET inhibitor PHA-665752 induced apoptosis in these cells. The subsets of gastric cancer cells defined by a response to c-Src or MET inhibitors were distinct and nonoverlapping. Our results suggest that c-Src is a promising target for the treatment of gastric cancer and that analysis of MET amplification might optimize patient selection for treatment with c-Src inhibitors. Mol Cancer Ther; 9(5); 1188–97. ©2010 AACR.
Data from Predicting continuous values of prognostic markers in breast cancer from microarray gene expression profiles
Authors: Gruvberger-Saal Sofia K. , Edén Patrik , Ringnér Markus , Baldetorp Bo , Chebil Gunilla , Borg Åke , Fernö Mårten , Peterson Carsten , Meltzer Paul S.
Published: April 2023

Abstract
The prognostic and treatment-predictive markers currently in use for breast cancer are commonly based on the protein levels of individual genes (e.g., steroid receptors) or aspects of the tumor phenotype, such as histological grade and percentage of cells in the DNA synthesis phase of the cell cycle. Microarrays have previously been used to classify binary classes in breast cancer such as estrogen receptor (ER)-α status. To test whether the properties and specific values of conventional prognostic markers are encoded within tumor gene expression profiles, we have analyzed 48 well-characterized primary tumors from lymph node-negative breast cancer patients using 6728-element cDNA microarrays. In the present study, we used artificial neural networks trained with tumor gene expression data to predict the ER protein values on a continuous scale. Furthermore, we determined a gene expression profile-directed threshold for ER protein level to redefine the cutoff between ER-positive and ER-negative classes that may be more biologically relevant. With a similar approach, we studied the prediction of other prognostic parameters such as percentage cells in the S phase of the cell cycle (SPF), histological grade, DNA ploidy status, and progesterone receptor status. Interestingly, there was a consistent reciprocal relationship in expression levels of the genes important for both ER and SPF prediction. This and similar studies may be used to increase our understanding of the biology underlying these markers as well as to improve the currently available prognostic markers for breast cancer.
Data from Nutlin-3a Induces Cytoskeletal Rearrangement and Inhibits the Migration and Invasion Capacity of p53 Wild-Type Cancer Cells
Authors: Moran Diarmuid M. , Maki Carl G.
Published: April 2023

Abstract
MDM2 is an E3 ubiquitin ligase that binds and ubiquitinates the tumor suppressor protein p53, leading to its proteasomal degradation. Nutlin-3a (Nutlin) is a preclinical drug that binds MDM2 and prevents the interaction between MDM2 and p53, leading to p53 stabilization and activation of p53 signaling events. Previous studies have reported that Nutlin promotes growth arrest and/or apoptosis in cancer cells that express wild-type p53. In the current study, Nutlin treatment caused a cytoskeletal rearrangement in p53 wild-type human cancer cells from multiple etiologies. Specifically, Nutlin decreased actin stress fibers and reduced the size and number of focal adhesions in treated cells. This process was dependent on p53 expression but was independent of p21 expression and growth arrest. Consistent with this, Nutlin-treated cells failed to form filamentous actin–based motility structures (lamellipodia) and displayed significantly decreased directional persistence in response to migratory cues. Finally, chemotactic assays showed a p53-dependent/p21-independent decrease in migratory and invasive capacity of Nutlin-treated cells. Taken together, these findings reveal that Nutlin treatment can inhibit the migration and invasion capacity of p53 wild-type cells, adding to the potential therapeutic benefit of Nutlin and other small molecule MDM2 inhibitors. Mol Cancer Ther; 9(4); 895–905. ©2010 AACR.
Data from Efficacy of IGFBP7 for treatment of metastatic melanoma and other cancers in mouse models and human cell lines
Authors: Wajapeyee Narendra , Kapoor Varun , Mahalingam Meera , Green Michael R.
Published: April 2023

Abstract
We recently identified the secreted protein IGFBP7 as a factor required for an activated BRAF oncogene to induce senescence or apoptosis in primary human cells. In human melanomas containing an activating BRAF mutation (BRAF-positive melanomas), IGFBP7 is epigenetically silenced, which seems to be a critical step in melanoma genesis. Restoration of IGFBP7 function by the addition of recombinant IGFBP7 (rIGFBP7) induces apoptosis in BRAF-positive human melanoma cell lines, and systemically administered rIGFBP7 markedly suppresses the growth of BRAF-positive primary tumors in xenografted mice. Here we further evaluate the role of IGFBP7 in the treatment of BRAF-positive melanoma and other malignancies. We find that in human metastatic melanoma samples IGFBP7 is epigenetically silenced and at an even higher frequency than that found in primary melanomas. Using a murine experimental metastasis assay, we show that systemic administration of rIGFBP7 markedly suppresses the growth of metastatic disease and prolongs survival. An analysis of the NCI60 panel of human cancer cell lines reveals that in addition to melanoma, IGFBP7 induces apoptosis in several other cancer types, in particular colorectal cancer cell lines. In general, IGFBP7 induces apoptosis in human cancer cell lines that have an activating mutation in BRAF or RAS, and that are sensitive to chemical inhibition of BRAF-MEK-ERK signaling. Significantly, systemically administered rIGFBP7 blocks the growth of colorectal tumors containing an activating RAS or BRAF mutation in mouse xenografts. The results presented here, in conjunction with those from previous studies, justify the further development of IGFBP7 as an anticancer agent. [Mol Cancer Ther 2009;8(11):3009–14]
Data from Bortezomib up-regulates activated signal transducer and activator of transcription-3 and synergizes with inhibitors of signal transducer and activator of transcription-3 to promote head and neck squamous cell carcinoma cell death
Authors: Li Changyou , Zang Yan , Sen Malabika , Leeman-Neill Rebecca J. , Man David SK. , Grandis Jennifer R. , Johnson Daniel E.
Published: April 2023

Abstract
Head and neck squamous cell carcinomas (HNSCC) are commonly resistant to conventional chemotherapy drugs and exhibit overexpression of signal transducer and activator of transcription 3 (STAT3). STAT3 promotes both the proliferation and survival of HNSCC cells. Recent studies have shown that the proteasome inhibitor bortezomib shows cytotoxic activity against HNSCC in vitro and in vivo. We report that treatment of HNSCC cells with bortezomib led to up-regulation of total STAT3 protein and the phosphorylated/activated form of STAT3, as well as an increase in cellular STAT3 activity. This suggested that the ability of bortezomib to kill HNSCC cells may be blunted due to induction of STAT3, and inhibition of STAT3 may be a useful means for improving bortezomib efficacy. Indeed, forced expression of dominant-active STAT3 inhibited bortezomib-induced cell death, whereas expression of dominant-negative STAT3 served to enhance killing by this compound. In addition, specific inhibition of STAT3 with the use of a STAT3 decoy oligonucleotide resulted in enhancement of bortezomib-induced apoptosis signaling and loss of clonogenic survival. Cotreatment of HNSCC cells with bortezomib and guggulsterone, a naturally occurring compound known to inhibit STAT3 activation, led to synergistic activation of cell death and loss of clonogenic survival. In summary, these studies show that bortezomib induces the expression of active STAT3, a key growth- promoting protein in HNSCC cells. Furthermore, our findings suggest that the therapeutic activity of bortezomib against HNSCC may be markedly improved by cotreatment with molecular targeting agents against STAT3. [Mol Cancer Ther 2009;8(8):2211–20]
Data from Pharmacologic Inactivation of Kinase Suppressor of Ras1 Sensitizes Epidermal Growth Factor Receptor and Oncogenic Ras-Dependent Tumors to Ionizing Radiation Treatment
Authors: Xiao Hongyan , Zhang Qingbei , Shen Jikun , Bindokas Vytas , Xing H. Rosie
Published: April 2023

Abstract
Selective enhancement of tumor response to radiation therapy is a highly attractive objective, but it has not been met clinically. Gain-of-function Ras (gf) signaling via hyperactivation of receptor tyrosine kinases, such as the epidermal growth factor receptor (EGFR), or via oncogenic mutation of Ras is shown to confer radioresistance and requires the engagement of the Raf/MEK/ERK pathway. However, upstream mediators of such interaction in cancer cells that could be targeted for radiosensitization have not been identified and characterized. Here, we provide original observations both in vitro and in vivo that kinase suppressor of Ras1 (KSR1) is a new target for reversing gf Ras-mediated radioresistance. We employed EGFR-dependent A431 squamous cell carcinoma (SCC) and genetically defined the molecular function of KSR1 in irradiation-induced Raf/MEK/ERK activation. In vitro KSR1 inactivation via genetic inhibition of its expression or kinase function abrogated ionizing radiation–induced activation of the Raf/MEK/ERK2 cascade, enhanced the cytotoxic effect of radiation, and achieved radiosensitization associated with inhibition of DNA damage repair and enhancement of clonogenic death. In vivo pharmacologic inactivation of KSR1 by KSR1 AS-ODN infusion leads to radiosensitization in EGFR-dependent A431 SCC and in oncogenic K-Ras-driven A549 human non–small cell lung carcinoma. These observations collectively establish KSR1 as a novel target for radiosensitization and show the feasibility of using KSR1 AS-ODN as a radiosensitizer for treating gf Ras-dependent human malignancies. Identification of such mediators of gf Ras signaling in response to irradiation holds promises for improving the therapeutic efficacy of radiation therapy and our ability to eradicate tumor. Mol Cancer Ther; 9(10); 2724–36. ©2010 AACR.
Data from 17-Allylamino-17-Demethoxygeldanamycin and MEK1/2 Inhibitors Kill GI Tumor Cells via Ca2+-Dependent Suppression of GRP78/BiP and Induction of Ceramide and Reactive Oxygen Species
Authors: Walker Teneille , Mitchell Clint , Park Margaret A. , Yacoub Adly , Rahmani Mohamed , Häussinger Dieter , Reinehr Roland , Voelkel-Johnson Christina , Fisher Paul B. , Grant Steven , Dent Paul
Published: April 2023

Abstract
The present studies determine in greater detail the molecular mechanisms upstream of the CD95 death receptor by which geldanamycin heat shock protein 90 inhibitors and mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 1/2 (MEK1/2) inhibitors interact to kill carcinoma cells. MEK1/2 inhibition enhanced 17-allylamino-17-demethoxygeldanamycin (17AAG) toxicity that was suppressed in cells deleted for mutant active RAS that were nontumorigenic but was magnified in isogenic tumorigenic cells expressing Harvey RAS V12 or Kirsten RAS D13. MEK1/2 inhibitor and 17AAG treatment increased intracellular Ca2+ levels and reduced GRP78/BiP expression in a Ca2+-dependent manner. GRP78/BiP overexpression, however, also suppressed drug-induced intracellular Ca2+ levels. MEK1/2 inhibitor and 17AAG treatment increased reactive oxygen species (ROS) levels that were blocked by quenching Ca2+ or overexpression of GRP78/BiP. MEK1/2 inhibitor and 17AAG treatment activated CD95 and inhibition of ceramide synthesis; ROS or Ca2+ quenching blocked CD95 activation. In SW620 cells that are patient matched to SW480 cells, MEK1/2 inhibitor and 17AAG toxicity was significantly reduced, which correlated with a lack of CD95 activation and lower expression of ceramide synthase 6 (LASS6). Overexpression of LASS6 in SW620 cells enhanced drug-induced CD95 activation and enhanced tumor cell killing. Inhibition of ceramide signaling abolished drug-induced ROS generation but not drug-induced cytosolic Ca2+ levels. Thus, treatment of tumor cells with MEK1/2 inhibitor and 17AAG induces cytosolic Ca2+ and loss of GRP78/BiP function, leading to de novo ceramide synthesis pathway activation that plays a key role in ROS generation and CD95 activation. Mol Cancer Ther; 9(5); 1378–95. ©2010 AACR.
Data from Biological properties of potent inhibitors of class I phosphatidylinositide 3-kinases: from PI-103 through PI-540, PI-620 to the oral agent GDC-0941
Authors: Raynaud Florence I. , Eccles Suzanne A. , Patel Sonal , Alix Sonia , Box Gary , Chuckowree Irina , Folkes Adrian , Gowan Sharon , De Haven Brandon Alexis , Di Stefano Francesca , Hayes Angela , Henley Alan T. , Lensun Letitia , Pergl-Wilson Giles , Robson Anthony , Saghir Nahid , Zhyvoloup Alexander , McDonald Edward , Sheldrake Peter , Shuttleworth Stephen , Valenti Melanie , Wan Nan Chi , Clarke Paul A. , Workman Paul
Published: April 2023

Abstract
The phosphatidylinositide 3-kinase pathway is frequently deregulated in human cancers and inhibitors offer considerable therapeutic potential. We previously described the promising tricyclic pyridofuropyrimidine lead and chemical tool compound PI-103. We now report the properties of the pharmaceutically optimized bicyclic thienopyrimidine derivatives PI-540 and PI-620 and the resulting clinical development candidate GDC-0941. All four compounds inhibited phosphatidylinositide 3-kinase p110α with IC50 ≤ 10 nmol/L. Despite some differences in isoform selectivity, these agents exhibited similar in vitro antiproliferative properties to PI-103 in a panel of human cancer cell lines, with submicromolar potency in PTEN-negative U87MG human glioblastoma cells and comparable phosphatidylinositide 3-kinase pathway modulation. PI-540 and PI-620 exhibited improvements in solubility and metabolism with high tissue distribution in mice. Both compounds gave improved antitumor efficacy over PI-103, following i.p. dosing in U87MG glioblastoma tumor xenografts in athymic mice, with treated/control values of 34% (66% inhibition) and 27% (73% inhibition) for PI-540 (50 mg/kg b.i.d.) and PI-620 (25 mg/kg b.i.d.), respectively. GDC-0941 showed comparable in vitro antitumor activity to PI-103, PI-540, and PI-620 and exhibited 78% oral bioavailability in mice, with tumor exposure above 50% antiproliferative concentrations for >8 hours following 150 mg/kg p.o. and sustained phosphatidylinositide 3-kinase pathway inhibition. These properties led to excellent dose-dependent oral antitumor activity, with daily p.o. dosing at 150 mg/kg achieving 98% and 80% growth inhibition of U87MG glioblastoma and IGROV-1 ovarian cancer xenografts, respectively. Together, these data support the development of GDC-0941 as a potent, orally bioavailable inhibitor of phosphatidylinositide 3-kinase. GDC-0941 has recently entered phase I clinical trials. [Mol Cancer Ther 2009;8(7):1725–38] [Mol Cancer Ther 2009;8(7):1725–38]
Data from Small-molecule inhibitor of USP7/HAUSP ubiquitin protease stabilizes and activates p53 in cells
Authors: Colland Frédéric , Formstecher Etienne , Jacq Xavier , Reverdy Céline , Planquette Cécile , Conrath Susan , Trouplin Virginie , Bianchi Julie , Aushev Vasily N. , Camonis Jacques , Calabrese Alessandra , Borg-Capra Catherine , Sippl Wolfgang , Collura Vincent , Boissy Guillaume , Rain Jean-Christophe , Guedat Philippe , Delansorne Rémi , Daviet Laurent
Published: April 2023

Abstract
Deregulation of the ubiquitin/proteasome system has been implicated in the pathogenesis of many human diseases, including cancer. Ubiquitin-specific proteases (USP) are cysteine proteases involved in the deubiquitination of protein substrates. Functional connections between USP7 and essential viral proteins and oncogenic pathways, such as the p53/Mdm2 and phosphatidylinositol 3-kinase/protein kinase B networks, strongly suggest that the targeting of USP7 with small-molecule inhibitors may be useful for the treatment of cancers and viral diseases. Using high-throughput screening, we have discovered HBX 41,108, a small-molecule compound that inhibits USP7 deubiquitinating activity with an IC50 in the submicromolar range. Kinetics data indicate an uncompetitive reversible inhibition mechanism. HBX 41,108 was shown to affect USP7-mediated p53 deubiquitination in vitro and in cells. As RNA interference-mediated USP7 silencing in cancer cells, HBX 41,108 treatment stabilized p53, activated the transcription of a p53 target gene without inducing genotoxic stress, and inhibited cancer cell growth. Finally, HBX 41,108 induced p53-dependent apoptosis as shown in p53 wild-type and null isogenic cancer cell lines. We thus report the identification of the first lead-like inhibitor against USP7, providing a structural basis for the development of new anticancer drugs.[Mol Cancer Ther 2009;8(8):2286–95]
Data from Hyaluronan Inhibits Postchemotherapy Tumor Regrowth in a Colon Carcinoma Xenograft Model
Authors: Mueller Barbara M. , Schraufstatter Ingrid U. , Goncharova Valentina , Povaliy Tatiana , DiScipio Richard , Khaldoyanidi Sophia K.
Published: April 2023

Abstract
Bone marrow hypoplasia and pancytopenia are among the most undesirable sequelae of chemotherapy for the treatment of cancer. We recently showed that hyaluronan (HA) facilitates hematopoietic recovery in tumor-free animals receiving chemotherapeutic agents. However, following a chemotherapeutic regimen in tumor-bearing animals, it is possible that residual tumor cells might respond to systemic injections of HA. Thus, in this study, we investigated the effect of HA on the regrowth of residual tumor cells following chemotherapy. As a model, we used the HCT-8 human colon carcinoma cell line, which expresses the HA receptor CD44, binds exogenous HA, and is susceptible to a chemotherapy protocol containing irinotecan and 5-fluorouracil in a human/mouse xenograft model. HCT-8 cells were implanted in severe combined immunodeficient mice, followed by irinotecan/5-fluorouracil treatment. After three rounds of chemotherapy, residual tumors were allowed to regrow in the presence or absence of HA. The dynamics of tumor regrowth in the group treated with HA was slower compared with the control group. By week 5 after tumor implantation, the difference in the size of regrown tumors was statistically significant and correlated with lower proliferation and higher apoptosis in HA-treated tumors as compared with controls. This finding provides evidence that HA treatment does not stimulate but delays the growth of residual cancer cells, which is an important parameter in establishing whether the use of HA can enhance current chemotherapeutic strategies. Mol Cancer Ther; 9(11); 3024–32. ©2010 AACR.
Data from High-Content Phenotypic Profiling of Drug Response Signatures across Distinct Cancer Cells
Authors: Caie Peter D. , Walls Rebecca E. , Ingleston-Orme Alexandra , Daya Sandeep , Houslay Tom , Eagle Rob , Roberts Mark E. , Carragher Neil O.
Published: April 2023

Abstract
The application of high-content imaging in conjunction with multivariate clustering techniques has recently shown value in the confirmation of cellular activity and further characterization of drug mode of action following pharmacologic perturbation. However, such practical examples of phenotypic profiling of drug response published to date have largely been restricted to cell lines and phenotypic response markers that are amenable to basic cellular imaging. As such, these approaches preclude the analysis of both complex heterogeneous phenotypic responses and subtle changes in cell morphology across physiologically relevant cell panels. Here, we describe the application of a cell-based assay and custom designed image analysis algorithms designed to monitor morphologic phenotypic response in detail across distinct cancer cell types. We further describe the integration of these methods with automated data analysis workflows incorporating principal component analysis, Kohonen neural networking, and kNN classification to enable rapid and robust interrogation of such data sets. We show the utility of these approaches by providing novel insight into pharmacologic response across four cancer cell types, Ovcar3, MiaPaCa2, and MCF7 cells wild-type and mutant for p53. These methods have the potential to drive the development of a new generation of novel therapeutic classes encompassing pharmacologic compositions or polypharmacology in appropriate disease context. Mol Cancer Ther; 9(6); 1913–26. ©2010 AACR.
Data from MK-2206, an Allosteric Akt Inhibitor, Enhances Antitumor Efficacy by Standard Chemotherapeutic Agents or Molecular Targeted Drugs In vitro and In vivo
Authors: Hirai Hiroshi , Sootome Hiroshi , Nakatsuru Yoko , Miyama Katsuyoshi , Taguchi Shunsuke , Tsujioka Kyoko , Ueno Yoko , Hatch Harold , Majumder Pradip K. , Pan Bo-Sheng , Kotani Hidehito
Published: April 2023

Abstract
The serine/threonine kinase Akt lies at a critical signaling node downstream of phosphatidylinositol-3-kinase and is important in promoting cell survival and inhibiting apoptosis. An Akt inhibitor may be particularly useful for cancers in which increased Akt signaling is associated with reduced sensitivity to cytotoxic agents or receptor tyrosine kinase inhibitors. We evaluated the effect of a novel allosteric Akt inhibitor, MK-2206, in combination with several anticancer agents. In vitro, MK-2206 synergistically inhibited cell proliferation of human cancer cell lines in combination with molecular targeted agents such as erlotinib (an epidermal growth factor receptor inhibitor) or lapatinib (a dual epidermal growth factor receptor/human epidermal growth factor receptor 2 inhibitor). Complementary inhibition of erlotinib-insensitive Akt phosphorylation by MK-2206 was one mechanism of synergism, and a synergistic effect was found even in erlotinib-insensitive cell lines. MK-2206 also showed synergistic responses in combination with cytotoxic agents such as topoisomerase inhibitors (doxorubicin, camptothecin), antimetabolites (gemcitabine, 5-fluorouracil), anti-microtubule agents (docetaxel), and DNA cross-linkers (carboplatin) in lung NCI-H460 or ovarian A2780 tumor cells. The synergy with docetaxel depended on the treatment sequence; a schedule of MK-2206 dosed before docetaxel was not effective. MK-2206 suppressed the Akt phosphorylation that is induced by carboplatin and gemcitabine. In vivo, MK-2206 in combination with these agents exerted significantly more potent tumor inhibitory activities than each agent in the monotherapy setting. These findings suggest that Akt inhibition may augment the efficacy of existing cancer therapeutics; thus, MK-2206 is a promising agent to treat cancer patients who receive these cytotoxic and/or molecular targeted agents. Mol Cancer Ther; 9(7); 1956–67. ©2010 AACR.
Data from ClC-3 expression enhances etoposide resistance by increasing acidification of the late endocytic compartment
Authors: Weylandt Karsten H. , Nebrig Maxim , Jansen-Rosseck Nils , Amey Joanna S. , Carmena David , Wiedenmann Bertram , Higgins Christopher F. , Sardini Alessandro
Published: April 2023

Abstract
Resistance to anticancer drugs and consequent failure of chemotherapy is a complex problem severely limiting therapeutic options in metastatic cancer. Many studies have shown a role for drug efflux pumps of the ATP-binding cassette transporters family in the development of drug resistance. ClC-3, a member of the CLC family of chloride channels and transporters, is expressed in intracellular compartments of neuronal cells and involved in vesicular acidification. It has previously been suggested that acidification of intracellular organelles can promote drug resistance by increasing drug sequestration. Therefore, we hypothesized a role for ClC-3 in drug resistance. Here, we show that ClC-3 is expressed in neuroendocrine tumor cell lines, such as BON, LCC-18, and QGP-1, and localized in intracellular vesicles colabeled with the late endosomal/lysosomal marker LAMP-1. ClC-3 overexpression increased the acidity of intracellular vesicles, as assessed by acridine orange staining, and enhanced resistance to the chemotherapeutic drug etoposide by almost doubling the IC50 in either BON or HEK293 cell lines. Prevention of organellar acidification, by inhibition of the vacuolar H+-ATPase, reduced etoposide resistance. No expression of common multidrug resistance transporters, such as P-glycoprotein or multidrug-related protein-1, was detected in either the BON parental cell line or the derivative clone overexpressing ClC-3. The probable mechanism of enhanced etoposide resistance can be attributed to the increase of vesicular acidification as consequence of ClC-3 overexpression. This study therefore provides first evidence for a role of intracellular CLC proteins in the modulation of cancer drug resistance. [Mol Cancer Ther 2007;6(3):979–86]
Data from Potent in vitro and in vivo anticancer activities of des-methyl, des-amino pateamine A, a synthetic analogue of marine natural product pateamine A
Authors: Kuznetsov Galina , Xu Qunli , Rudolph-Owen Lori , TenDyke Karen , Liu Junke , Towle Murray , Zhao Nanding , Marsh Joanne , Agoulnik Sergei , Twine Natalie , Parent Lana , Chen Zhihong , Shie Jue-Lon , Jiang Yimin , Zhang Huiming , Du Hong , Boivin Roch , Wang Yuan , Romo Daniel , Littlefield Bruce A.
Published: April 2023

Abstract
We report here that des-methyl, des-amino pateamine A (DMDA-PatA), a structurally simplified analogue of the marine natural product pateamine A, has potent antiproliferative activity against a wide variety of human cancer cell lines while showing relatively low cytotoxicity against nonproliferating, quiescent human fibroblasts. DMDA-PatA retains almost full in vitro potency in P-glycoprotein-overexpressing MES-SA/Dx5-Rx1 human uterine sarcoma cells that are significantly resistant to paclitaxel, suggesting that DMDA-PatA is not a substrate for P-glycoprotein-mediated drug efflux. Treatment of proliferating cells with DMDA-PatA leads to rapid shutdown of DNA synthesis in the S phase of the cell cycle. Cell-free studies show that DMDA-PatA directly inhibits DNA polymerases α and γ in vitro albeit at concentrations considerably higher than those that inhibit cell proliferation. DMDA-PatA shows potent anticancer activity in several human cancer xenograft models in nude mice, including significant regressions observed in the LOX and MDA-MB-435 melanoma models. DMDA-PatA thus represents a promising natural product-based anticancer agent that warrants further investigation.[Mol Cancer Ther 2009;8(5):1250–60]
Data from The alkylphospholipid perifosine induces apoptosis of human lung cancer cells requiring inhibition of Akt and activation of the extrinsic apoptotic pathway
Authors: Elrod Heath A. , Lin Yi-Dan , Yue Ping , Wang Xuerong , Lonial Sagar , Khuri Fadlo R. , Sun Shi-Yong
Published: April 2023

Abstract
The Akt inhibitor, perifosine, is an alkylphospholipid exhibiting antitumor properties and is currently in phase II clinical trials for various types of cancer. The mechanisms by which perifosine exerts its antitumor effects, including the induction of apoptosis, are not well understood. The current study focused on the effects of perifosine on the induction of apoptosis and its underlying mechanisms in human non–small cell lung cancer (NSCLC) cells. Perifosine, at clinically achievable concentration ranges of 10 to 15 μmol/L, effectively inhibited the growth and induced apoptosis of NSCLC cells. Perifosine inhibited Akt phosphorylation and reduced the levels of total Akt. Importantly, enforced activation of Akt attenuated perifosine-induced apoptosis. These results indicate that Akt inhibition is necessary for perifosine-induced apoptosis. Despite the activation of both caspase-8 and caspase-9, perifosine strikingly induced the expression of the tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) receptor, death receptor 5, and down-regulated cellular FLICE-inhibitory protein (c-FLIP), an endogenous inhibitor of the extrinsic apoptotic pathway, with limited modulatory effects on the expression of other genes including Bcl-2, Bcl-XL, PUMA, and survivin. Silencing of either caspase-8 or death receptor 5 attenuated perifosine-induced apoptosis. Consistently, further down-regulation of c-FLIP expression with c-FLIP small interfering RNA sensitized cells to perifosine-induced apoptosis, whereas enforced overexpression of ectopic c-FLIP conferred resistance to perifosine. Collectively, these data indicate that activation of the extrinsic apoptotic pathway plays a critical role in perifosine-induced apoptosis. Moreover, perifosine cooperates with TRAIL to enhance the induction of apoptosis in human NSCLC cells, thus warranting future in vivo and clinical evaluation of perifosine in combination with TRAIL in the treatment of NSCLC. [Mol Cancer Ther 2007;6(7):2029–38]
Data from Determinants of sensitivity to lovastatin-induced apoptosis in multiple myeloma
Authors: Wong W. Wei-Lynn , Clendening James W. , Martirosyan Anna , Boutros Paul C. , Bros Christina , Khosravi Fereshteh , Jurisica Igor , Stewart A. Keith , Bergsagel P. Leif , Penn Linda Z.
Published: April 2023

Abstract
Statins, commonly used to treat hypercholesterolemia, have been shown to trigger tumor-specific apoptosis in certain cancers, including multiple myeloma (MM), a plasma cell malignancy with poor prognosis. In this article, we show that of a panel of 17 genetically distinct MM cell lines, half were sensitive to statin-induced apoptosis and, despite pharmacodynamic evidence of drug uptake and activity, the remainder were insensitive. Sensitive cells were rescued from lovastatin-induced apoptosis by mevalonate, geranylgeranyl PPi, and partially by farnesyl PPi, highlighting the importance of isoprenylation. Expression profiling revealed that Rho GTPase mRNAs were differentially expressed upon lovastatin exposure in sensitive cells, yet ectopic expression of constitutively active Rho or Ras proteins was insufficient to alter sensitivity to lovastatin-induced apoptosis. This suggests that sensitivity involves more than one isoprenylated protein and that statins trigger apoptosis by blocking many signaling cascades, directly or indirectly deregulated by the oncogenic lesions of the tumor cell. Indeed, clustering on the basis of genetic abnormalities was shown to be significantly associated with sensitivity (P = 0.003). These results suggest that statins may be a useful molecular targeted therapy in the treatment of a subset of MM. [Mol Cancer Ther 2007;6(6):1886–97]
Data from 2-Methoxy antimycin reveals a unique mechanism for Bcl-xL inhibition
Authors: Schwartz Pamela S. , Manion Michael K. , Emerson Christine B. , Fry John S. , Schulz Craig M. , Sweet Ian R. , Hockenbery David M.
Published: April 2023

Abstract
Overexpression of Bcl-xL in multiple cancers correlates with resistance to chemotherapy and radiation therapy, and provides a rationale for development of small-molecule Bcl-xL inhibitors. Based on knockout studies, nonneoplastic cells also require Bcl-xL survival functions, particularly when challenged with cytotoxic agents. We analyze the selective cytotoxicity of one Bcl-xL inhibitor, 2-methoxy antimycin A, toward cells with excess exogenous Bcl-xL in isogenic cell line pairs. This selectivity, characteristic of a gain-of-function mechanism, is not shared by other known Bcl-xL inhibitors, including BH3I-2, HA14-1, ABT-737, gossypol, or the stapled BH3 helical peptide SAHB-BID. We show that Bcl-xL overexpression induces a shift in energy metabolism from oxidative phosphorylation to glycolysis. Treatment with 2-methoxy antimycin A acutely reverses the metabolic effects of Bcl-xL, causing mitochondrial hyperpolarization and a progressive increase in mitochondrial NAD(P)H. We identify an additional small-molecule Bcl-xL inhibitor, NSC 310343, establishing a class of Bcl-xL inhibitors with gain-of-function activity. In contrast to other Bcl-xL inhibitors, combining gain-of-function Bcl-xL inhibitors with a standard inducer of apoptosis, staurosporine, enhances selective cytotoxicity toward Bcl-xL–overexpressing cells. These results provide an example of the intersection of bioenergetic metabolism and Bcl-xL functions and suggest a metabolic basis for the gain-of-function mechanism of Bcl-xL inhibitors. [Mol Cancer Ther 2007;6(7):2073–80]
Data from Prediction of individual response to platinum/paclitaxel combination using novel marker genes in ovarian cancers
Authors: Komatsu Masaaki , Hiyama Keiko , Tanimoto Keiji , Yunokawa Mayu , Otani Keiko , Ohtaki Megu , Hiyama Eiso , Kigawa Junzo , Ohwada Michitaka , Suzuki Mitsuaki , Nagai Nobutaka , Kudo Yoshiki , Nishiyama Masahiko
Published: April 2023

Abstract
We attempted to identify potent marker genes using a new statistical analysis and developed a prediction system for individual response to platinum/paclitaxel combination chemotherapy in ovarian cancer patients based on the hypothesis that expression analysis of a set of the key drug sensitivity genes for platinum and paclitaxel could allow us to predict therapeutic response to the combination. From 10 human ovarian cancer cell lines, genes correlative in the expression levels with cytotoxicities of cisplatin (CDDP) and paclitaxel were chosen. We first selected five reliable prediction markers for the two drugs from 22 genes already known as sensitivity determinants and then identified another 8 novel genes through a two-dimensional mixed normal model using oligomicroarray expression data. Using expression data of genes quantified by real-time reverse transcription-PCR, we fixed the best linear model, which converted the quantified expression data into an IC50 of each drug. Multiple regression analysis of the selected genes yielded three prediction formulae for in vitro activity of CDDP and paclitaxel. In the same way, using the same genes selected in vitro, we then attempted to develop prediction formulae for progression-free survival to the platinum/paclitaxel combination. We therefore constructed possible formulae using different sets of 13 selected marker genes (5 known and 8 novel genes): Utility confirmation analyses using another nine test samples seemed to show that the formulae using a set of 8 novel marker genes alone could accurately predict progression-free survival (r = 0.683; P = 0.042). [Mol Cancer Ther 2006;5(3):767–75]
Data from Nuclear factor-κB activation: a molecular therapeutic target for estrogen receptor–negative and epidermal growth factor receptor family receptor–positive human breast cancer
Authors: Singh Sindhu , Shi Qian , Bailey Shannon T. , Palczewski Marek J. , Pardee Arthur B. , Iglehart J. Dirk , Biswas Debajit K.
Published: April 2023

Abstract
Nuclear factor-κB (NF-κB), a transcription factor with pleotropic effects, is a downstream mediator of growth signaling in estrogen receptor (ER)-negative and erbB family particularly erbB2 (HER-2/neu) receptor–positive cancer. We previously reported activation of NF-κB in ER-negative breast cancer cells and breast tumor specimens, but the consequence of inhibiting NF-κB activation in this subclass of breast cancer has not been shown. In this study, we investigated the role of NF-κB activation by studying the tumorigenic potential of cells expressing genetically manipulated, inducible, dominant-negative inhibitory κB kinase (IKK) β in xenograft tumor model. Conditional inhibition of NF-κB activation by the inducible expression of dominant-negative IKKβ simultaneously blocked cell proliferation, reinstated apoptosis, and dramatically blocked xenograft tumor formation. Secondly, the humanized anti-erbB2 antibody trastuzumab (Herceptin) and the specific IKK inhibitor NF-κB essential modifier–binding domain peptide both blocked NF-κB activation and cell proliferation and reinstated apoptosis in two ER-negative and erbB2-positive human breast cancer cell lines that are used as representative model systems. Combinations of these two target-specific inhibitors synergistically blocked cell proliferation at concentrations that were singly ineffective. Inhibition of NF-κB activation with two other low molecular weight compounds, PS1145 and PS341, which inhibited IKK activity and proteasome-mediated phosphorylated inhibitory κB protein degradation, respectively, blocked erbB2-mediated cell growth and reversed antiapoptotic machinery. These results implicate NF-κB activation in the tumorigenesis and progression of ER-negative breast cancer. It is postulated that this transcription factor and its activation cascade offer therapeutic targets for erbB2-positive and ER-negative breast cancer. [Mol Cancer Ther 2007;6(7):1973–82]
Data from Multiple signaling pathways must be targeted to overcome drug resistance in cell lines derived from melanoma metastases
Authors: Smalley Keiran S.M. , Haass Nikolas K. , Brafford Patricia A. , Lioni Mercedes , Flaherty Keith T. , Herlyn Meenhard
Published: April 2023

Abstract
Although >66% of melanomas harbor activating mutations in BRAF and exhibit constitutive activity in the mitogen-activated protein kinase/extracellular signal–regulated kinase kinase (MEK)/extracellular signal–regulated kinase signaling pathway, it is unclear how effective MEK inhibition will be as a sole therapeutic strategy for melanoma. We investigated the anticancer activity of MEK inhibition in a panel of cell lines derived from radial growth phase (WM35) and vertical growth phase (WM793) of primary melanomas and metastatic melanomas (1205Lu, 451Lu, WM164, and C8161) in a three-dimensional spheroid model and found that the metastatic lines were completely resistant to MEK inhibition (U0126 and PD98059) but the earlier stage cell lines were not. Similarly, these same metastatic melanoma lines were also resistant to inhibitors of the phosphatidylinositol 3-kinase/Akt pathway (LY294002 and wortmannin). Under adherent culture conditions, the MEK inhibitors blocked growth through the induction of cell cycle arrest and up-regulation of p27, but this was readily reversible following inhibitor washout. However, when the phosphatidylinositol 3-kinase and MEK inhibitors were combined, the growth and invasion of the metastatic melanoma three-dimensional spheroids were blocked. Taken together, these results suggest that the most aggressive melanomas are resistant to strategies targeting one signaling pathway and that multiple signaling pathways may need to be targeted for maximal therapeutic efficacy. It is further suggested that BRAF mutational status is not predictive of response to MEK inhibition under three-dimensional culture conditions. [Mol Cancer Ther 2006;5(5):1136–44]
Data from Potentiation of antileukemic therapies by Smac mimetic, LBW242: effects on mutant FLT3-expressing cells
Authors: Weisberg Ellen , Kung Andrew L. , Wright Renee D. , Moreno Daisy , Catley Laurie , Ray Arghya , Zawel Leigh , Tran Mary , Cools Jan , Gilliland Gary , Mitsiades Constantine , McMillin Douglas W. , Jiang Jingrui , Hall-Meyers Elizabeth , Griffin James D.
Published: April 2023

Abstract
Members of the inhibitor of apoptosis protein (IAP) family play a role in mediating apoptosis. Studies suggest that these proteins may be a viable target in leukemia because they have been found to be variably expressed in acute leukemias and are associated with chemosensitivity, chemoresistance, disease progression, remission, and patient survival. Another promising therapeutic target, FLT3, is mutated in about one third of acute myelogenous leukemia (AML) patients; promising results have recently been achieved in clinical trials investigating the effects of the protein tyrosine kinase inhibitor PKC412 on AML patients harboring mutations in the FLT3 protein. Of growing concern, however, is the development of drug resistance resulting from the emergence of point mutations in targeted tyrosine kinases used for treatment of acute leukemia patients. One approach to overriding resistance is to combine structurally unrelated inhibitors and/or inhibitors of different signaling pathways. The proapoptotic IAP inhibitor, LBW242, was shown in proliferation studies done in vitro to enhance the killing of PKC412-sensitive and PKC412-resistant cell lines expressing mutant FLT3 when combined with either PKC412 or standard cytotoxic agents (doxorubicin and Ara-c). In addition, in an in vivo imaging assay using bioluminescence as a measure of tumor burden, a total of 12 male NCr-nude mice were treated for 10 days with p.o. administration of vehicle, LBW242 (50 mg/kg/day), PKC412 (40 mg/kg/day), or a combination of LBW242 and PKC412; the lowest tumor burden was observed in the drug combination group. Finally, the combination of LBW242 and PKC412 was sufficient to override stromal-mediated viability signaling conferring resistance to PKC412. [Mol Cancer Ther 2007;6(7):1951–61]
On the phylogenetic status of Contortylenchus genitalicola Kosaka & Ogura, 1993
Authors: Kanzaki Natsumi , Kosaka Hajime , Fujimori Yuta , Akiba Mitsuteru
Published: April 2023

Contortylenchus genitalicola is a unique species within the genus. It parasitises the ovary or testis of the longhorn beetle, Monochamus alternatus, and has a neotylenchid-like culturable mycetophagous phase within its life cycle, while the other species in the genus parasitise bark beetles and have a typical unculturable allantonematid life cycle. Because the species was described based solely on morphology, it was necessary to confirm the phylogenetic and taxonomic status of C. genitalicola. A molecular phylogenetic analysis of the species based on ribosomal RNA sequences revealed that C. genitalicola forms a well-supported clade with Contortylenchus spp. isolated from bark beetles, an unidentified allantonematid from Iran, and ‘Deladenus cf. laricis’ isolated from the metallic wood-boring beetle, Agrilus macer LeConte (Coleoptera: Buprestidae), in the USA. The generic status of C. genitalicola was supported by phylogenetic analysis, and the analysis also suggests that the diversity of the genus could be higher than currently expected.
How can legal interpretation change the legal order into legal disorder? (Lessons from the Czech Republic)
Authors: Beran Karel
Published: April 2023

An opinion long prevailed in the Czech Republic that a judge is bound, in his decision-making, only by statutory law and by international treaties which, according to the Constitution of the Czech Republic, have priority over statutory law. The fact that a judge is bound by statutory law was mostly understood in that the judge is bound by the “word of the statutes”. A judge thus could not be formally bound by someone else’s interpretation of the statutes, i.e. by case law. However, both these basic assumptions began to change radically in the Czech Republic, especially following the adoption of the new Civil Code in 2012. This article therefore aims to present the transformations in the binding effect of case law in the Czech Republic at the beginning of the 21st century and, in doing so, it will concentrate on the yet insufficiently examined question of limits to judicial law-making in the sense of constructive interpretation of statutory law by courts.

When a judge applies the law, and thus necessarily also interprets it, he must ask two fundamental questions: (i) Whether he/she is bound by interpretation of the statutory law which has already been provided by someone else, and the judge is thus obliged to adhere to this line of interpretation. (ii) How should he/she proceed in the interpretation, which comprises the question of what methods of interpretation he/she should use, in what order and what significance should be attached to these methods?

The ambition of this article is to show why a “discursive” or “conditional binding effect of case law”, on the one hand, and a judge’s competence to interpret the law, on the other hand, can lead to fragmentation of the Czech legal order and contribute to transformation of the law from an order to a disorder, and how these unfavourable tendencies can be eliminated, or at least mitigated.