bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Chemogenetic Evaluation of the Mitotic Kinesin CENP-E Reveals a Critical Role in Triple-Negative Breast Cancer
Authors: Kung Pei-Pei , Martinez Ricardo , Zhu Zhou , Zager Michael , Blasina Alessandra , Rymer Isha , Hallin Jill , Xu Meirong , Carroll Christopher , Chionis John , Wells Peter , Kozminski Kirk , Fan Jeffery , Guicherit Oivin , Huang Buwen , Cui Mei , Liu Chaoting , Huang Zhongdong , Sistla Anand , Yang Jennifer , Murray Brion W.
Published: April 2023

Abstract
Breast cancer patients with tumors lacking the three diagnostic markers (ER, PR, and HER2) are classified as triple-negative (primarily basal-like) and have poor prognosis because there is no disease-specific therapy available. To address this unmet medical need, gene expression analyses using more than a thousand breast cancer samples were conducted, which identified elevated centromere protein E (CENP-E) expression in the basal-a molecular subtype relative to other subtypes. CENP-E, a mitotic kinesin component of the spindle assembly checkpoint, is shown to be induced in basal-a tumor cell lines by the mitotic spindle inhibitor drug docetaxel. CENP-E knockdown by inducible shRNA reduces basal-a breast cancer cell viability. A potent, selective CENP-E inhibitor (PF-2771) was used to define the contribution of CENP-E motor function to basal-like breast cancer. Mechanistic evaluation of PF-2771 in basal-a tumor cells links CENP-E–dependent molecular events (e.g., phosphorylation of histone H3 Ser-10; phospho-HH3-Ser10) to functional outcomes (e.g., chromosomal congression defects). Across a diverse panel of breast cell lines, CENP-E inhibition by PF-2771 selectively inhibits proliferation of basal breast cancer cell lines relative to premalignant ones and its response correlates with the degree of chromosomal instability. Pharmacokinetic–pharmacodynamic efficacy analysis in a basal-a xenograft tumor model shows that PF-2771 exposure is well correlated with increased phospho-HH3-Ser10 levels and tumor growth regression. Complete tumor regression is observed in a patient-derived, basal-a breast cancer xenograft tumor model treated with PF-2771. Tumor regression is also observed with PF-2771 in a taxane-resistant basal-a model. Taken together, CENP-E may be an effective therapeutic target for patients with triple-negative/basal-a breast cancer. Mol Cancer Ther; 13(8); 2104–15. ©2014 AACR.
Data from Preclinical Evaluation of Multistep Targeting of Diasialoganglioside GD2 Using an IgG-scFv Bispecific Antibody with High Affinity for GD2 and DOTA Metal Complex
Authors: Cheal Sarah M. , Xu Hong , Guo Hong-fen , Zanzonico Pat B. , Larson Steven M. , Cheung Nai-Kong
Published: April 2023

Abstract
Bispecific antibodies (BsAb) have proven to be useful targeting vectors for pretargeted radioimmunotherapy (PRIT). We sought to overcome key PRIT limitations such as high renal radiation exposure and immunogenicity (e.g., of streptavidin–antibody fusions), to advance clinical translation of this PRIT strategy for diasialoganglioside GD2-positive [GD2(+)] tumors. For this purpose, an IgG-scFv BsAb was engineered using the sequences for the anti-GD2 humanized monoclonal antibody hu3F8 and C825, a murine scFv antibody with high affinity for the chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) complexed with β-particle–emitting radiometals such as 177Lu and 90Y. A three-step regimen, including hu3F8-C825, a dextran-based clearing agent, and p-aminobenzyl-DOTA radiolabeled with 177Lu (as 177Lu-DOTA-Bn; t1/2 = 6.71 days), was optimized in immunocompromised mice carrying subcutaneous human GD2(+) neuroblastoma (NB) xenografts. Absorbed doses for tumor and normal tissues were approximately 85 cGy/MBq and ≤3.7 cGy/MBq, respectively, with therapeutic indices (TI) of 142 for blood and 23 for kidney. A therapy study (n = 5/group; tumor volume, 240 ± 160 mm3) with three successive PRIT cycles (total 177Lu: ∼33 MBq; tumor dose ∼3,400 cGy), revealed complete tumor response in 5 of 5 animals, with no recurrence up to 28 days after treatment. Tumor ablation was confirmed histologically in 4 of 5 mice, and normal organs showed minimal overall toxicities. All nontreated mice required sacrifice within 12 days (>1.0-cm3 tumor volume). We conclude that this novel anti-GD2 PRIT approach has sufficient TI to successfully ablate subcutaneous GD2(+)-NB in mice while sparing kidney and bone marrow. Mol Cancer Ther; 13(7); 1803–12. ©2014 AACR.
Data from Generation of a Canine Anti-EGFR (ErbB-1) Antibody for Passive Immunotherapy in Dog Cancer Patients
Authors: Singer Josef , Fazekas Judit , Wang Wei , Weichselbaumer Marlene , Matz Miroslawa , Mader Alexander , Steinfellner Willibald , Meitz Sarah , Mechtcheriakova Diana , Sobanov Yuri , Willmann Michael , Stockner Thomas , Spillner Edzard , Kunert Renate , Jensen-Jarolim Erika
Published: April 2023

Abstract
Passive immunotherapy with monoclonal antibodies represents a cornerstone of human anticancer therapies, but has not been established in veterinary medicine yet. As the tumor-associated antigen EGFR (ErbB-1) is highly conserved between humans and dogs, and considering the effectiveness of the anti-EGFR antibody cetuximab in human clinical oncology, we present here a “caninized” version of this antibody, can225IgG, for comparative oncology studies. Variable region genes of 225, the murine precursor of cetuximab, were fused with canine constant heavy gamma and kappa chain genes, respectively, and transfected into Chinese hamster ovary (CHO) DUKX-B11 cells. Of note, 480 clones were screened and the best clones were selected according to productivity and highest specificity in EGFR-coated ELISA. Upon purification with Protein G, the recombinant cetuximab-like canine IgG was tested for integrity, correct assembly, and functionality. Specific binding to the surface of EGFR-overexpressing cells was assessed by flow cytometry and immunofluorescence; moreover, binding to canine mammary tissue was demonstrated by immunohistochemistry. In cell viability and proliferation assays, incubation with can225IgG led to significant tumor cell growth inhibition. Moreover, this antibody mediated significant tumor cell killing via phagocytosis in vitro. We thus present here, for the first time, the generation of a canine IgG antibody and its hypothetical structure. On the basis of its cetuximab-like binding site, on the one hand, and the expression of a 91% homologous EGFR molecule in canine cancer, on the other hand, this antibody may be a promising research compound to establish passive immunotherapy in dog patients with cancer. Mol Cancer Ther; 13(7); 1777–90. ©2014 AACR.
Data from PTEN Expression as a Predictor of Response to Focal Adhesion Kinase Inhibition in Uterine Cancer
Authors: Thanapprapasr Duangmani , Previs Rebecca A. , Hu Wei , Ivan Cristina , Armaiz-Pena Guillermo N. , Dorniak Piotr L. , Hansen Jean M. , Rupaimoole Rajesha , Huang Jie , Dalton Heather J. , Ali-Fehmi Rouba , Coleman Robert L. , Sood Anil K.
Published: April 2023

Abstract
PTEN is known to be frequently mutated in uterine cancer and also dephosphorylates FAK. Here, we examined the impact of PTEN alterations on the response to treatment with a FAK inhibitor (GSK2256098). In vitro and in vivo therapeutic experiments were carried out using PTEN-mutated and PTEN-wild-type models of uterine cancer alone and in combination with chemotherapy. Treatment with GSK2256098 resulted in greater inhibition of pFAKY397 in PTEN-mutated (Ishikawa) than in PTEN-wild-type (Hec1A) cells. Ishikawa cells were more sensitive to GSK2256098 than the treated Hec1A cells. Ishikawa cells were transfected with a wild-type PTEN construct and pFAKY397 expression was unchanged after treatment with GSK2256098. Decreased cell viability and enhanced sensitivity to chemotherapy (paclitaxel and topotecan) in combination with GSK2256098 was observed in Ishikawa cells as compared with Hec1a cells. In the Ishikawa orthoptopic murine model, treatment with GSK2256098 resulted in lower tumor weights and fewer metastases than mice inoculated with Hec1A cells. Tumors treated with GSK2256098 had lower microvessel density (CD31), less cellular proliferation (Ki67), and higher apoptosis (TUNEL) rates in the Ishikawa model when compared with the Hec1a model. From a large cohort of evaluable patients, increased FAK and pFAKY397 expression levels were significantly related to poor overall survival. Moreover, PTEN levels were inversely related to pFAKY397 expression. These preclinical data demonstrate that PTEN-mutated uterine cancer responds better to FAK inhibition than does PTEN wild-type cancer. Therefore, PTEN could be a biomarker for predicting response to FAK-targeted therapy during clinical development. Mol Cancer Ther; 14(6); 1466–75. ©2015 AACR.
Data from DCDT2980S, an Anti-CD22-Monomethyl Auristatin E Antibody–Drug Conjugate, Is a Potential Treatment for Non-Hodgkin Lymphoma
Authors: Li Dongwei , Poon Kirsten Achilles , Yu Shang-Fan , Dere Randall , Go MaryAnn , Lau Jeffrey , Zheng Bing , Elkins Kristi , Danilenko Dimitry , Kozak Katherine R. , Chan Pamela , Chuh Josefa , Shi Xiaoyan , Nazzal Denise , Fuh Franklin , McBride Jacqueline , Ramakrishnan Vanitha , de Tute Ruth , Rawstron Andy , Jack Andrew S. , Deng Rong , Chu Yu-Waye , Dornan David , Williams Marna , Ho William , Ebens Allen , Prabhu Saileta , Polson Andrew G.
Published: April 2023

Abstract
Antibody–drug conjugates (ADC), potent cytotoxic drugs linked to antibodies via chemical linkers, allow specific targeting of drugs to neoplastic cells. We have used this technology to develop the ADC DCDT2980S that targets CD22, an antigen with expression limited to B cells and the vast majority of non-Hodgkin lymphomas (NHL). DCDT2980S consists of a humanized anti-CD22 monoclonal IgG1 antibody with a potent microtubule-disrupting agent, monomethyl auristatin E (MMAE), linked to the reduced cysteines of the antibody via a protease cleavable linker, maleimidocaproyl-valine-citrulline-p-aminobenzoyloxycarbonyl (MC-vc-PAB). We describe the efficacy, safety, and pharmacokinetics of DCDT2980S in animal models to assess its potential as a therapeutic for the treatment of B-cell malignancies. We did not find a strong correlation between in vitro or in vivo efficacy and CD22 surface expression, nor a correlation of sensitivity to free drug and in vitro potency. We show that DCDT2980S was capable of inducing complete tumor regression in xenograft mouse models of NHL and can be more effective than rituximab plus combination chemotherapy at drug exposures that were well tolerated in cynomolgus monkeys. These results suggest that DCDT2980S has an efficacy, safety, and pharmacokinetics profile that support potential treatment of NHL. Mol Cancer Ther; 12(7); 1255–65. ©2013 AACR.
Data from Three-Dimensional Cell Culture-Based Screening Identifies the Anthelmintic Drug Nitazoxanide as a Candidate for Treatment of Colorectal Cancer
Authors: Senkowski Wojciech , Zhang Xiaonan , Olofsson Maria Hägg , Isacson Ruben , Höglund Urban , Gustafsson Mats , Nygren Peter , Linder Stig , Larsson Rolf , Fryknäs Mårten
Published: April 2023

Abstract
Because dormant cancer cells in hypoxic and nutrient-deprived regions of solid tumors provide a major obstacle to treatment, compounds targeting those cells might have clinical benefits. Here, we describe a high-throughput drug screening approach, using glucose-deprived multicellular tumor spheroids (MCTS) with inner hypoxia, to identify compounds that specifically target this cell population. We used a concept of drug repositioning—using known molecules for new indications. This is a promising strategy to identify molecules for rapid clinical advancement. By screening 1,600 compounds with documented clinical history, we aimed to identify candidates with unforeseen potential for repositioning as anticancer drugs. Our screen identified five molecules with pronounced MCTS-selective activity: nitazoxanide, niclosamide, closantel, pyrvinium pamoate, and salinomycin. Herein, we show that all five compounds inhibit mitochondrial respiration. This suggests that cancer cells in low glucose concentrations depend on oxidative phosphorylation rather than solely glycolysis. Importantly, continuous exposure to the compounds was required to achieve effective treatment. Nitazoxanide, an FDA-approved antiprotozoal drug with excellent pharmacokinetic and safety profile, is the only molecule among the screening hits that reaches high plasma concentrations persisting for up to a few hours after single oral dose. Nitazoxanide activated the AMPK pathway and downregulated c-Myc, mTOR, and Wnt signaling at clinically achievable concentrations. Nitazoxanide combined with the cytotoxic drug irinotecan showed anticancer activity in vivo. We here report that the FDA-approved anthelmintic drug nitazoxanide could be a potential candidate for advancement into cancer clinical trials. Mol Cancer Ther; 14(6); 1504–16. ©2015 AACR.
Data from Targeting Protein Tyrosine Phosphatase SHP2 for the Treatment of PTPN11-Associated Malignancies
Authors: Yu Bing , Liu Wei , Yu Wen-Mei , Loh Mignon L. , Alter Shawn , Guvench Olgun , MacKerell Alexander D. , Tang Li-Da , Qu Cheng-Kui
Published: April 2023

Abstract
Activating mutations in PTPN11 (encoding SHP2), a protein tyrosine phosphatase (PTP) that plays an overall positive role in growth factor and cytokine signaling, are directly associated with the pathogenesis of Noonan syndrome and childhood leukemias. Identification of SHP2-selective inhibitors could lead to the development of new drugs that ultimately serve as treatments for PTPN11-associated diseases. As the catalytic core of SHP2 shares extremely high homology to those of SHP1 and other PTPs that play negative roles in cell signaling, to identify selective inhibitors of SHP2 using computer-aided drug design, we targeted a protein surface pocket that is adjacent to the catalytic site, is predicted to be important for binding to phosphopeptide substrates, and has structural features unique to SHP2. From computationally selected candidate compounds, #220–324 effectively inhibited SHP2 activity with an IC50 of 14 μmol/L. Fluorescence titration experiments confirmed its direct binding to SHP2. This active compound was further verified for its ability to inhibit SHP2-mediated cell signaling and cellular function with minimal off-target effects. Furthermore, mouse myeloid progenitors with the activating mutation (E76K) in PTPN11 and patient leukemic cells with the same mutation were more sensitive to this inhibitor than wild-type cells. This study provides evidence that SHP2 is a “druggable” target for the treatment of PTPN11-associated diseases. As the small-molecule SHP2 inhibitor identified has a simple chemical structure, it represents an ideal lead compound for the development of novel anti-SHP2 drugs. Mol Cancer Ther; 12(9); 1738–48. ©2013 AACR.
Data from Inhibition of Akt Reverses the Acquired Resistance to Sorafenib by Switching Protective Autophagy to Autophagic Cell Death in Hepatocellular Carcinoma
Authors: Zhai Bo , Hu Fengli , Jiang Xian , Xu Jun , Zhao Dali , Liu Bing , Pan Shangha , Dong Xuesong , Tan Gang , Wei Zheng , Qiao Haiquan , Jiang Hongchi , Sun Xueying
Published: April 2023

Abstract
Sorafenib is the standard first-line systemic drug for advanced hepatocellular carcinoma (HCC), but the acquired resistance to sorafenib results in limited benefits. Activation of Akt is thought to be responsible for mediating the acquired resistance to sorafenib. The present study aims to examine the underlying mechanism and seek potential strategies to reverse this resistance. Two sorafenib-resistant HCC cell lines, which had been established from human HCC HepG2 and Huh7 cells, were refractory to sorafenib-induced growth inhibition and apoptosis in vitro and in vivo. Sustained exposure to sorafenib activated Akt via the feedback loop of mTOR but independent of protein phosphatase 2A in HCC cells. Autophagy participated in the resistance to sorafenib as inhibition of autophagy reduced the sensitivity of sorafenib-resistant HCC cells to sorafenib, whereas activation of autophagy by rapamycin had the opposite effect. However, rapamycin did not show a synergistic effect with sorafenib to inhibit cell proliferation, while it also activated Akt via a feedback mechanism in sorafenib-resistant HCC cells. Inhibition of Akt reversed the acquired resistance to sorafenib by switching autophagy from a cytoprotective role to a death-promoting mechanism in the sorafenib-resistant HCC cells. Akt inhibition by GDC0068 synergized with sorafenib to suppress the growth of sorafenib-resistant HCC tumors that possessed the sorafenib-resistant feature in vivo. The results have provided evidence for clinical investigation of GDC0068, a novel ATP-competitive pan-Akt inhibitor, as the second-line treatment after the failure of sorafenib-medicated molecular targeted therapy for advanced HCC. Mol Cancer Ther; 13(6); 1589–98. ©2014 AACR.
Data from Elevated Cyclin D1 Expression Is Predictive for a Benefit from TPF Induction Chemotherapy in Oral Squamous Cell Carcinoma Patients with Advanced Nodal Disease
Authors: Zhong Lai-Ping , Zhu Dong-Wang , William William N. , Liu Ying , Ma Jie , Yang Cheng-Zhe , Yang Xiao , Wang Li-Zhen , Li Jiang , Myers Jeffrey N. , Lee J. Jack , Zhang Chen-Ping , Zhang Zhi-Yuan
Published: April 2023

Abstract
Induction chemotherapy is likely to be effective for biologically distinct subgroups of patients with cancer with biomarker detection. To investigate the prognostic and predictive values of cyclin D1 expression in patients with oral squamous cell carcinoma (OSCC) who were treated in a prospective, randomized, phase III trial evaluating standard treatment with surgery and postoperative radiotherapy preceded or not by induction docetaxel, cisplatin, and 5-fluorouracil (TPF), immunohistochemical staining for cyclin D1 was conducted in pretreatment biopsy specimens of 232 out of 256 clinical stage III/IVA OSCC patients randomized to the clinical trial. Cyclin D1 index was estimated as the proportion of tumor cells with cyclin D1 nuclear staining. A low cyclin D1 expression predicted significantly better overall survival (OS; P = 0.001), disease-free survival (P = 0.005), locoregional recurrence-free survival (P = 0.003), and distant metastasis-free survival (DMFS; P = 0.002) compared with high cyclin D1 expression. Cyclin D1 expression levels were not predictive of benefit from induction TPF in the population overall. However, patients with nodal stage cN2 whose tumors had high cyclin D1 expression treated with TPF had significantly greater OS (P = 0.025) and DMFS (P = 0.025) when compared with high cyclin D1 cN2 patients treated with surgery upfront. Patients with low cyclin D1 level or patients with cN0 or cN1 disease did not benefit from induction chemotherapy. This study indicates that cN2 OSCC patients with high cyclin D1 expression can benefit from the addition of TPF induction chemotherapy to standard treatment. Cyclin D1 expression could be used as a biomarker in further validation studies to select cN2 patients that could benefit from induction therapy. Mol Cancer Ther; 12(6); 1112–21. ©2013 AACR.
Data from Antiandrogen Therapy with Hydroxyflutamide or Androgen Receptor Degradation Enhancer ASC-J9 Enhances BCG Efficacy to Better Suppress Bladder Cancer Progression
Authors: Shang Zhiqun , Li Yanjun , Zhang Minghao , Tian Jing , Han Ruifa , Shyr Chih-Rong , Messing Edward , Yeh Shuyuan , Niu Yuanjie , Chang Chawnshang
Published: April 2023

Abstract
Recent studies suggest that the androgen receptor (AR) might play important roles in influencing bladder cancer progression, yet its clinical application remains unclear. Here, we developed a new combined therapy with Bacillus Calmette–Guérin (BCG) and the AR degradation enhancer ASC-J9 or antiandrogen hydroxyflutamide (HF) to better suppress bladder cancer progression. Mechanism dissection revealed that ASC-J9 treatment enhanced BCG efficacy to suppress bladder cancer cell proliferation via increasing the recruitment of monocytes/macrophages that involved the promotion of BCG attachment/internalization to the bladder cancer cells through increased integrin-α5β1 expression and IL6 release. Such consequences might then enhance BCG-induced bladder cancer cell death via increased TNFα release. Interestingly, we also found that ASC-J9 treatment could directly promote BCG-induced HMGB1 release to enhance the BCG cytotoxic effects for suppression of bladder cancer cell growth. In vivo approaches also concluded that ASC-J9 could enhance the efficacy of BCG to better suppress bladder cancer progression in BBN-induced bladder cancer mouse models. Together, these results suggest that the newly developed therapy combining BCG plus ASC-J9 may become a novel therapy to better suppress bladder cancer progress. Mol Cancer Ther; 14(11); 2586–94. ©2015 AACR.
Data from Small Molecule Inhibition of MERTK Is Efficacious in Non–Small Cell Lung Cancer Models Independent of Driver Oncogene Status
Authors: Cummings Christopher T. , Zhang Weihe , Davies Kurtis D. , Kirkpatrick Gregory D. , Zhang Dehui , DeRyckere Deborah , Wang Xiaodong , Frye Stephen V. , Earp H. Shelton , Graham Douglas K.
Published: April 2023

Abstract
Treatment of non–small cell lung cancer (NSCLC) has been transformed by targeted therapies directed against molecular aberrations specifically activated within an individual patient's tumor. However, such therapies are currently only available against a small number of such aberrations, and new targets and therapeutics are needed. Our laboratory has previously identified the MERTK receptor tyrosine kinase (RTK) as a potential drug target in multiple cancer types, including NSCLC. We have recently developed UNC2025—the first-in-class small molecule inhibitor targeting MERTK with pharmacokinetic properties sufficient for clinical translation. Here, we utilize this compound to further validate the important emerging biologic functions of MERTK in lung cancer pathogenesis, to establish that MERTK can be effectively targeted by a clinically translatable agent, and to demonstrate that inhibition of MERTK is a valid treatment strategy in a wide variety of NSCLC lines independent of their driver oncogene status, including in lines with an EGFR mutation, a KRAS/NRAS mutation, an RTK fusion, or another or unknown driver oncogene. Biochemically, we report the selectivity of UNC2025 for MERTK, and its inhibition of oncogenic downstream signaling. Functionally, we demonstrate that UNC2025 induces apoptosis of MERTK-dependent NSCLC cell lines, while decreasing colony formation in vitro and tumor xenograft growth in vivo in murine models. These findings provide further evidence for the importance of MERTK in NSCLC, and demonstrate that MERTK inhibition by UNC2025 is a feasible, clinically relevant treatment strategy in a wide variety of NSCLC subtypes, which warrants further investigation in clinical trials. Mol Cancer Ther; 14(9); 2014–22. ©2015 AACR.
Data from Drug Repurposing Identifies a Synergistic Combination Therapy with Imatinib Mesylate for Gastrointestinal Stromal Tumor
Authors: Pessetto Ziyan Y. , Ma Yan , Hirst Jeff J. , von Mehren Margaret , Weir Scott J. , Godwin Andrew K.
Published: April 2023

Abstract
Gastrointestinal stromal tumor (GIST) is a rare and therefore often neglected disease. Introduction of the kinase inhibitor imatinib mesylate radically improved the clinical response of patients with GIST; however, its effects are often short-lived, with GISTs demonstrating a median time-to-progression of approximately two years. Although many investigational drugs, approved first for other cancers, have been subsequently evaluated for the management of GIST, few have greatly affected the overall survival of patients with advanced disease. We employed a novel, focused, drug-repurposing effort for GIST, including imatinib mesylate–resistant GIST, evaluating a large library of FDA-approved drugs regardless of current indication. As a result of the drug-repurposing screen, we identified eight FDA-approved drugs, including fludarabine phosphate (F-AMP), that showed synergy with and/or overcame resistance to imatinib mesylate. F-AMP induces DNA damage, Annexin V, and caspase-3/7 activities as the cytotoxic effects on GIST cells, including imatinib mesylate–resistant GIST cells. F-AMP and imatinib mesylate combination treatment showed greater inhibition of GIST cell proliferation when compared with imatinib mesylate and F-AMP alone. Successful in vivo experiments confirmed the combination of imatinib mesylate with F-AMP enhanced the antitumor effects compared with imatinib mesylate alone. Our results identified F-AMP as a promising, repurposed drug therapy for the treatment of GISTs, with potential to be administered in combination with imatinib mesylate or for treatment of imatinib mesylate–refractory tumors. Mol Cancer Ther; 13(10); 2276–87. ©2014 AACR.
Data from MCL-1 Is a Key Determinant of Breast Cancer Cell Survival: Validation of MCL-1 Dependency Utilizing a Highly Selective Small Molecule Inhibitor
Authors: Xiao Yu , Nimmer Paul , Sheppard George S. , Bruncko Milan , Hessler Paul , Lu Xin , Roberts-Rapp Lisa , Pappano William N. , Elmore Steven W. , Souers Andrew J. , Leverson Joel D. , Phillips Darren C.
Published: April 2023

Abstract
Hyperexpression of antiapoptotic BCL-2 family proteins allows cells to survive despite the receipt of signals that would ordinarily induce their deletion, a facet frequently exploited by tumors. Tumors addicted to the BCL-2 family proteins for survival are now being targeted therapeutically. For example, navitoclax, a BCL-2/BCL-XL/BCL-W inhibitor, is currently in phase I/II clinical trials in numerous malignancies. However, the related family member, MCL-1, limits the efficacy of navitoclax and other chemotherapeutic agents. In the present study, we identify breast cancer cell lines that depend upon MCL-1 for survival and subsequently determine the mechanism of apoptosis mediated by the MCL-1 selective inhibitor A-1210477. We demonstrate that apoptosis resulting from a loss in MCL-1 function requires expression of the proapoptotic protein BAK. However, expression of BCL-XL can limit apoptosis resulting from loss in MCL-1 function through sequestration of free BIM. Finally, we demonstrate substantial synergy between navitoclax and MCL-1 siRNA, the direct MCL-1 inhibitor A-1210477, or the indirect MCL-1 inhibitor flavopiridol, highlighting the therapeutic potential for inhibiting BCL-XL and MCL-1 in breast cancer. Mol Cancer Ther; 14(8); 1837–47. ©2015 AACR.
Data from A Novel Photodynamic Therapy Targeting Cancer Cells and Tumor-Associated Macrophages
Authors: Hayashi Noriyuki , Kataoka Hiromi , Yano Shigenobu , Tanaka Mamoru , Moriwaki Kazuhiro , Akashi Haruo , Suzuki Shugo , Mori Yoshinori , Kubota Eiji , Tanida Satoshi , Takahashi Satoru , Joh Takashi
Published: April 2023

Abstract
Tumor-associated macrophages (TAM) in cancer stroma play important roles for cancer cell growth, invasion, angiogenesis, and metastases. We synthesized a novel photosensitizer, mannose-conjugated chlorin (M-chlorin), designed to bind mannose receptors highly expressed on TAMs. We evaluated the newly available photodynamic therapy (PDT) with M-chlorin against gastric and colon cancer. We evaluated PDT with M-chlorin for in vitro cytotoxicity and apoptosis induction in cancer cells compared with chlorin alone and glucose-conjugated chlorin (G-chlorin). The subcellular localization of M-chlorin was observed by confocal microscopy, and the M-chlorin PDT effects against TAMs including THP-1–induced M2-polarized macrophages were evaluated. Anticancer effects were also investigated in an allograft model where cytotoxic effects against TAMs in the cancer cell stroma were analyzed by immunohistochemistry. M-chlorin PDT strongly induced cell death in cancer cells to almost the same extent as G-chlorin PDT by inducing apoptosis. M-chlorin was incorporated into cancer cells where it localized mainly in lysosomes and endoplasmic reticula. M-chlorin PDT revealed strong cytotoxicity for M2 macrophages induced from THP-1 cell lines, and it induced stronger cytotoxicity than G-chlorin PDT in the allograft model through killing both cancer cells and TAMs in the cancer stroma. The M-chlorin PDT produced strong cytotoxicity against cancer tissue by inducing apoptosis of both cancer cells and TAMs in the cancer stroma. This novel PDT thus stands as a new candidate for very effective, next-generation PDT. Mol Cancer Ther; 14(2); 452–60. ©2014 AACR.
Data from AGS67E, an Anti-CD37 Monomethyl Auristatin E Antibody–Drug Conjugate as a Potential Therapeutic for B/T-Cell Malignancies and AML: A New Role for CD37 in AML
Authors: Pereira Daniel S. , Guevara Claudia I. , Jin Liqing , Mbong Nathan , Verlinsky Alla , Hsu Ssucheng J. , Aviña Hector , Karki Sher , Abad Joseph D. , Yang Peng , Moon Sung-Ju , Malik Faisal , Choi Michael Y. , An Zili , Morrison Kendall , Challita-Eid Pia M. , Doñate Fernando , Joseph Ingrid B.J. , Kipps Thomas J. , Dick John E. , Stover David R.
Published: April 2023

Abstract
CD37 is a tetraspanin expressed on malignant B cells. Recently, CD37 has gained interest as a therapeutic target. We developed AGS67E, an antibody–drug conjugate that targets CD37 for the potential treatment of B/T-cell malignancies. It is a fully human monoclonal IgG2 antibody (AGS67C) conjugated, via a protease-cleavable linker, to the microtubule-disrupting agent monomethyl auristatin E (MMAE). AGS67E induces potent cytotoxicity, apoptosis, and cell-cycle alterations in many non-Hodgkin lymphoma (NHL) and chronic lymphocytic leukemia (CLL) cell lines and patient-derived samples in vitro. It also shows potent antitumor activity in NHL and CLL xenografts, including Rituxan-refractory models. During profiling studies to confirm the reported expression of CD37 in normal tissues and B-cell malignancies, we made the novel discovery that the CD37 protein was expressed in T-cell lymphomas and in AML. AGS67E bound to >80% of NHL and T-cell lymphomas, 100% of CLL and 100% of AML patient-derived samples, including CD34+CD38− leukemic stem cells. It also induced cytotoxicity, apoptosis, and cell-cycle alterations in AML cell lines and antitumor efficacy in orthotopic AML xenografts. Taken together, this study shows not only that AGS67E may serve as a potential therapeutic for B/T-cell malignancies, but it also demonstrates, for the first time, that CD37 is well expressed and a potential drug target in AML. Mol Cancer Ther; 14(7); 1650–60. ©2015 AACR.
Data from Endostatin Has ATPase Activity, Which Mediates Its Antiangiogenic and Antitumor Activities
Authors: Wang Shan , Lu Xin-an , Liu Peng , Fu Yan , Jia Lin , Zhan Shunli , Luo Yongzhang
Published: April 2023

Abstract
Endostatin is an endogenous angiogenesis inhibitor with broad-spectrum antitumor activities. Although the molecular mechanisms of endostatin have been extensively explored, the intrinsic biochemical characteristics of endostatin are not completely understood. Here, we revealed for the first time that endostatin embedded novel ATPase activity. Moreover, mutagenesis study showed that the ATPase activity of endostatin mutants positively correlated with effects on endothelial cell activities and tumor growth. E-M, an endostatin mutant with higher ATPase activity than that of wild-type (WT) endostatin, significantly increased endostatin-mediated inhibitory effects on endothelial cell proliferation, migration, tube formation, and adhesion. In vivo study showed that E-M displayed enhanced antitumor effects compared with WT. On the other hand, K96A, K96R, and E176A, endostatin mutants with lower ATPase activities than that of WT, showed reduced or comparable effects on targeting both in vitro endothelial cell activities and in vivo tumor angiogenesis and tumor growth. Furthermore, endostatin and its mutants exhibited distinct abilities in regulations of gene expression (Id1, Id3), cell signaling (Erk, p38, and Src phosphorylation), and intracellular ATP levels. Collectively, our study demonstrates that endostatin has novel ATPase activity, which mediates its antiangiogenic and antitumor activities, suggesting that construction of endostatin analogues with high ATPase activity may provide a new direction for the development of more potent antiangiogenic drugs. Mol Cancer Ther; 14(5); 1192–201. ©2015 AACR.
Data from MEDI-573, Alone or in Combination with Mammalian Target of Rapamycin Inhibitors, Targets the Insulin-like Growth Factor Pathway in Sarcomas
Authors: Zhong Haihong , Fazenbaker Christine , Breen Shannon , Chen Cui , Huang Jiaqi , Morehouse Christopher , Yao Yihong , Hollingsworth Robert E.
Published: April 2023

Abstract
MEDI-573 is a human antibody that neutralizes insulin-like growth factor (IGF) I and IGFII. IGFs are overexpressed in multiple types of cancer; their overexpression is a potential mechanism for resistance to IGFI receptor (IGFIR)-targeting therapy. Effects of IGF on cell proliferation, differentiation, and survival are mediated through its binding to and activation of IGFIR or insulin receptor A (IR-A). In this study, we measured the mRNA levels of IGFI, IGFII, and IGFIR in human pediatric sarcoma xenografts, and protein levels in sarcoma cell lines. MEDI-573 potently inhibited in vitro proliferation of sarcoma cell lines, with Ewing sarcoma cell lines being the most sensitive. In addition, MEDI-573 inhibited IGFI- and IGFII-induced sarcoma cell proliferation in vitro. The effect of MEDI-573 on IGF signaling was also examined. Treatment with MEDI-573 markedly reduced levels of pIGFIR, pIR-A, and pAKT and significantly blocked IGFI- and IGFII-induced activation of the IGFIR and AKT pathways. MEDI-573 inhibited the growth of sarcoma xenografts in vivo and inhibition correlated with neutralization of IGFI and IGFII. Combination of MEDI-573 with either rapamycin or AZD2014, another mTOR inhibitor (mTORi), significantly enhanced the antitumor activity of MEDI-573, and this response correlated with modulation of AKT and mTOR signaling. In summary, sarcoma cells respond to autocrine or paracrine growth stimulation by IGFI and IGFII, and inhibition of IGFI and IGFII by MEDI-573 results in significant slowing of tumor growth rate in sarcoma models, particularly in Ewing sarcoma. These data provide evidence for the potential benefits of MEDI-573 and mTORi combinations in patients with Ewing sarcoma. Mol Cancer Ther; 13(11); 2662–73. ©2014 AACR.
Data from Modeling of Patient-Derived Xenografts in Colorectal Cancer
Authors: Katsiampoura Anastasia , Raghav Kanwal , Jiang Zhi-Qin , Menter David G. , Varkaris Andreas , Morelli Maria P. , Manuel Shanequa , Wu Ji , Sorokin Alexey V. , Rizi Bahar Salimian , Bristow Christopher , Tian Feng , Airhart Susan , Cheng Mingshan , Broom Bradley M. , Morris Jeffrey , Overman Michael J. , Powis Garth , Kopetz Scott
Published: April 2023

Abstract
Developing realistic preclinical models using clinical samples that mirror complex tumor biology and behavior are vital to advancing cancer research. While cell line cultures have been helpful in generating preclinical data, the genetic divergence between these and corresponding primary tumors has limited clinical translation. Conversely, patient-derived xenografts (PDX) in colorectal cancer are highly representative of the genetic and phenotypic heterogeneity in the original tumor. Coupled with high-throughput analyses and bioinformatics, these PDXs represent robust preclinical tools for biomarkers, therapeutic target, and drug discovery. Successful PDX engraftment is hypothesized to be related to a series of anecdotal variables namely, tissue source, cancer stage, tumor grade, acquisition strategy, time to implantation, exposure to prior systemic therapy, and genomic heterogeneity of tumors. Although these factors at large can influence practices and patterns related to xenotransplantation, their relative significance in determining the success of establishing PDXs is uncertain. Accordingly, we systematically examined the predictive ability of these factors in establishing PDXs using 90 colorectal cancer patient specimens that were subcutaneously implanted into immunodeficient mice. Fifty (56%) PDXs were successfully established. Multivariate analyses showed tissue acquisition strategy [surgery 72.0% (95% confidence interval (CI): 58.2–82.6) vs. biopsy 35% (95% CI: 22.1%–50.6%)] to be the key determinant for successful PDX engraftment. These findings contrast with current empiricism in generating PDXs and can serve to simplify or liberalize PDX modeling protocols. Better understanding the relative impact of these factors on efficiency of PDX formation will allow for pervasive integration of these models in care of colorectal cancer patients. Mol Cancer Ther; 16(7); 1435–42. ©2017 AACR.
Data from Synergistic Combination of Novel Tubulin Inhibitor ABI-274 and Vemurafenib Overcomes Vemurafenib Acquired Resistance in BRAFV600E Melanoma
Authors: Wang Jin , Chen Jianjun , Miller Duane D. , Li Wei
Published: April 2023

Abstract
Acquired clinical resistance to vemurafenib, a selective BRAFV600E inhibitor, arises frequently after short-term chemotherapy. Because inhibitions of targets in the RAF–MEK–ERK pathway result in G0–G1 cell-cycle arrest, vemurafenib-resistant cancer cells are expected to escape this cell-cycle arrest and progress to the subsequent G2–M phase. We hypothesized that a combined therapy using vemurafenib with a G2–M phase blocking agent will trap resistant cells and overcome vemurafenib resistance. To test this hypothesis, we first determined the combination index (CI) values of our novel tubulin inhibitor ABI-274 and vemurafenib on parental human A375 and MDA-MB-435 melanoma cell lines to be 0.32 and 0.1, respectively, suggesting strong synergy for the combination. We then developed an A375RF21 subline with significant acquired resistance to vemurafenib and confirmed the strong synergistic effect. Next, we studied the potential mechanisms of overcoming vemurafenib resistance. Flow cytometry confirmed that the combination of ABI-274 and vemurafenib synergistically arrested cells in the G1–G2–M phase, and significantly increased apoptosis in both parental A375 and the vemurafenib-resistant A375RF21 cells. Western blot analysis revealed that the combination treatment effectively reduced the level of phosphorylated and total AKT, activated the apoptosis cascade, and increased cleaved caspase-3 and cleaved PARP, but had no significant influence on the level of extracellular signal–regulated kinase (ERK) phosphorylation. Finally, in vivo coadministration of vemurafenib with ABI-274 showed strong synergistic efficacy in the vemurafenib-resistant xenograft model in nude mice. Overall, these results offer a rational combination strategy to significantly enhance the therapeutic benefit in patients with melanoma who inevitably become resistant to current vemurafenib therapy. Mol Cancer Ther; 13(1); 16–26. ©2013 AACR.
Data from Apratoxin A Shows Novel Pancreas-Targeting Activity through the Binding of Sec 61
Authors: Huang Kuan-Chun , Chen Zhihong , Jiang Yimin , Akare Sandeep , Kolber-Simonds Donna , Condon Krista , Agoulnik Sergei , Tendyke Karen , Shen Yongchun , Wu Kuo-Ming , Mathieu Steven , Choi Hyeong-wook , Zhu Xiaojie , Shimizu Hajime , Kotake Yoshihiko , Gerwick William H. , Uenaka Toshimitsu , Woodall-Jappe Mary , Nomoto Kenichi
Published: April 2023

Abstract
Apratoxin A is a natural product with potent antiproliferative activity against many human cancer cell lines. However, we and other investigators observed that it has a narrow therapeutic window in vivo. Previous mechanistic studies have suggested its involvement in the secretory pathway as well as the process of chaperone-mediated autophagy. Still the link between the biologic activities of apratoxin A and its in vivo toxicity has remained largely unknown. A better understanding of this relationship is critically important for any further development of apratoxin A as an anticancer drug. Here, we describe a detailed pathologic analysis that revealed a specific pancreas-targeting activity of apratoxin A, such that severe pancreatic atrophy was observed in apratoxin A–treated animals. Follow-up tissue distribution studies further uncovered a unique drug distribution profile for apratoxin A, showing high drug exposure in pancreas and salivary gland. It has been shown previously that apratoxin A inhibits the protein secretory pathway by preventing cotranslational translocation. However, the molecule targeted by apratoxin A in this pathway has not been well defined. By using a 3H-labeled apratoxin A probe and specific Sec 61α/β antibodies, we identified that the Sec 61 complex is the molecular target of apratoxin A. We conclude that apratoxin A in vivo toxicity is likely caused by pancreas atrophy due to high apratoxin A exposure. Mol Cancer Ther; 15(6); 1208–16. ©2016 AACR.
Data from Chikusetsusaponin IVa Butyl Ester (CS-IVa-Be), a Novel IL6R Antagonist, Inhibits IL6/STAT3 Signaling Pathway and Induces Cancer Cell Apoptosis
Authors: Yang Jie , Qian Shihui , Cai Xueting , Lu Wuguang , Hu Chunping , Sun Xiaoyan , Yang Yang , Yu Qiang , Gao S. Paul , Cao Peng
Published: April 2023

Abstract
The activation of IL6/STAT3 signaling is associated with the pathogenesis of many cancers. Agents that suppress IL6/STAT3 signaling have cancer-therapeutic potential. In this study, we found that chikusetsusaponin IVa butyl ester (CS-IVa-Be), a triterpenoid saponin extracted from Acanthopanas gracilistylus W.W.Smith, induced cancer cell apoptosis. CS-IVa-Be inhibited constitutive and IL6-induced STAT3 activation, repressed STAT3 DNA-binding activity, STAT3 nuclear translocation, IL6-induced STAT3 luciferase reporter activity, IL6-induced STAT3-regulated antiapoptosis gene expression in MDA-MB-231 cells, and IL6-induced TF-1 cell proliferation. Surprisingly, CS-IVa-Be inhibited IL6 family cytokines rather than other cytokines induced STAT3 activation. Further studies indicated that CS-IVa-Be is an antagonist of IL6 receptor via directly binding to the IL6Rα with a Kd of 663 ± 74 nmol/L and the GP130 (IL6Rβ) with a Kd of 1,660 ± 243 nmol/L, interfering with the binding of IL6 to IL6R (IL6Rα and GP130) in vitro and in cancer cells. The inhibitory effect of CS-IVa-Be on the IL6–IL6Rα–GP130 interaction was relatively specific as CS-IVa-Be showed higher affinity to IL6Rα than to LIFR (Kd: 4,910 ± 1,240 nmol/L) and LeptinR (Kd: 4,990 ± 915 nmol/L). We next demonstrated that CS-IVa-Be not only directly induced cancer cell apoptosis but also sensitized MDA-MB-231 cells to TRAIL-induced apoptosis via upregulating DR5. Our findings suggest that CS-IVa-Be as a novel IL6R antagonist inhibits IL6/STAT3 signaling pathway and sensitizes the MDA-MB-231 cells to TRAIL-induced cell death. Mol Cancer Ther; 15(6); 1190–200. ©2016 AACR.
Data from Targeting Lineage-specific MITF Pathway in Human Melanoma Cell Lines by A-485, the Selective Small-molecule Inhibitor of p300/CBP
Authors: Wang Rui , He Yupeng , Robinson Valerie , Yang Ziping , Hessler Paul , Lasko Loren M. , Lu Xin , Bhathena Anahita , Lai Albert , Uziel Tamar , Lam Lloyd T.
Published: April 2023

Abstract
Metastatic melanoma is responsible for approximately 80% of deaths from skin cancer. Microphthalmia-associated transcription factor (MITF) is a melanocyte-specific transcription factor that plays an important role in the differentiation, proliferation, and survival of melanocytes as well as in melanoma oncogenesis. MITF is amplified in approximately 15% of patients with metastatic melanoma. However, no small-molecule inhibitors of MITF currently exist. MITF was shown to associate with p300/CBP, members of the KAT3 family of histone acetyltransferase. p300 and CREB-binding protein (p300/CBP) regulate a wide range of cellular events such as senescence, apoptosis, cell cycle, DNA damage response, and cellular differentiation. p300/CBP act as transcriptional coactivators for multiple proteins in cancers, including oncogenic transcription factors such as MITF. In this study, we showed that our novel p300/CBP catalytic inhibitor, A-485, induces senescence in multiple melanoma cell lines, similar to silencing expression of EP300 (encodes p300) or MITF. We did not observe apoptosis and increase invasiveness upon A-485 treatment. A-485 regulates the expression of MITF and its downstream signature genes in melanoma cell lines undergoing senescence. In addition, expression and copy number of MITF is significantly higher in melanoma cell lines that undergo A-485–induced senescence than resistant cell lines. Finally, we showed that A-485 inhibits histone-H3 acetylation but did not displace p300 at promoters of MITF and its putative downstream genes. Taken together, we provide evidence that p300/CBP inhibition suppressed the melanoma-driven transcription factor, MITF, and could be further exploited as a potential therapy for treating melanoma.
Data from Metformin Suppresses Tumor Progression by Inactivating Stromal Fibroblasts in Ovarian Cancer
Authors: Xu Sen , Yang Zongyuan , Jin Ping , Yang Xin , Li Xiaoting , Wei Xiao , Wang Ya , Long Sixiang , Zhang Taoran , Chen Gang , Sun Chaoyang , Ma Ding , Gao Qinglei
Published: April 2023

Abstract
Ovarian cancer is a devastating disease due to its high incidence of relapse and chemoresistance. The tumor microenvironment, especially the tumor stroma compartment, was proven to contribute tremendously to the unsatisfactory chemotherapeutic efficacy in ovarian cancer. Cytotoxic agents not only effect tumor cells, but also modulate the phenotype and characteristics of the vast stromal cell population, which can in turn alter the tumor cell response to chemointervention. In this study, we focused on the tumor stroma response to cytotoxic agents and the subsequent effect on the ovarian cancer tumor cells. First, we found a significant stromal overexpression of IL6 in patient samples that received cisplatin-based treatment, which was further validated in purified fibroblasts challenged with cisplatin. Stromal fibroblast–derived IL6 was proven to mediate ovarian cancer tumor cell chemoresistance. For the first time, we found that the tumor stroma of patients with routine metformin administration exhibited lower IL6 expression. Thus, we presumed that metformin was a potent alleviator of stromal inflammation in ovarian cancer. We found that metformin partly reversed cisplatin-stimulated IL6 secretion in the stromal fibroblasts and attenuated fibroblast-facilitated tumor growth in 3D organotypic cocultures and murine xenograft models. Mechanistically, we found that metformin inhibited IL6 secretion via suppressing NFκB signaling, an upstream controller of stromal inflammation. Collectively, our findings introduced a novel mechanism of metformin in suppressing ovarian cancer progression through diminishing chemotherapy-induced stromal activation. Therefore, we provide an alternative therapeutic option in targeting stromal inflammation and a potential scheme of combination therapy to improve the chemosensitivity in ovarian cancer. Mol Cancer Ther; 17(6); 1291–302. ©2018 AACR.