bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Orally Bioavailable and Blood–Brain Barrier-Penetrating ATM Inhibitor (AZ32) Radiosensitizes Intracranial Gliomas in Mice
Authors: Karlin Jeremy , Allen Jasmine , Ahmad Syed F. , Hughes Gareth , Sheridan Victoria , Odedra Rajesh , Farrington Paul , Cadogan Elaine B. , Riches Lucy C. , Garcia-Trinidad Antonio , Thomason Andrew G. , Patel Bhavika , Vincent Jennifer , Lau Alan , Pike Kurt G. , Hunt Thomas A. , Sule Amrita , Valerie Nicholas C.K. , Biddlestone-Thorpe Laura , Kahn Jenna , Beckta Jason M. , Mukhopadhyay Nitai , Barlaam Bernard , Degorce Sebastien L. , Kettle Jason , Colclough Nicola , Wilson Joanne , Smith Aaron , Barrett Ian P. , Zheng Li , Zhang Tianwei , Wang Yingchun , Chen Kan , Pass Martin , Durant Stephen T. , Valerie Kristoffer
Published: April 2023

Abstract
Inhibition of ataxia-telangiectasia mutated (ATM) during radiotherapy of glioblastoma multiforme (GBM) may improve tumor control by short-circuiting the response to radiation-induced DNA damage. A major impediment for clinical implementation is that current inhibitors have limited central nervous system (CNS) bioavailability; thus, the goal was to identify ATM inhibitors (ATMi) with improved CNS penetration. Drug screens and refinement of lead compounds identified AZ31 and AZ32. The compounds were then tested in vivo for efficacy and impact on tumor and healthy brain. Both AZ31 and AZ32 blocked the DNA damage response and radiosensitized GBM cells in vitro. AZ32, with enhanced blood–brain barrier (BBB) penetration, was highly efficient in vivo as radiosensitizer in syngeneic and human, orthotopic mouse glioma model compared with AZ31. Furthermore, human glioma cell lines expressing mutant p53 or having checkpoint-defective mutations were particularly sensitive to ATMi radiosensitization. The mechanism for this p53 effect involves a propensity to undergo mitotic catastrophe relative to cells with wild-type p53. In vivo, apoptosis was >6-fold higher in tumor relative to healthy brain after exposure to AZ32 and low-dose radiation. AZ32 is the first ATMi with oral bioavailability shown to radiosensitize glioma and improve survival in orthotopic mouse models. These findings support the development of a clinical-grade, BBB-penetrating ATMi for the treatment of GBM. Importantly, because many GBMs have defective p53 signaling, the use of an ATMi concurrent with standard radiotherapy is expected to be cancer-specific, increase the therapeutic ratio, and maintain full therapeutic effect at lower radiation doses. Mol Cancer Ther; 17(8); 1637–47. ©2018 AACR.
Data from Role of P53-Senescence Induction in Suppression of LNCaP Prostate Cancer Growth by Cardiotonic Compound Bufalin
Authors: Zhang Yong , Dong Yinhui , Melkus Michael W. , Yin Shutao , Tang Su-Ni , Jiang Peixin , Pramanik Kartick , Wu Wei , Kim Sangyub , Ye Min , Hu Hongbo , Lu Junxuan , Jiang Cheng
Published: April 2023

Abstract
Bufalin is a major cardiotonic compound in the traditional Chinese medicine, Chansu, prepared from toad skin secretions. Cell culture studies have suggested an anticancer potential involving multiple cellular processes, including differentiation, apoptosis, senescence, and angiogenesis. In prostate cancer cell models, P53-dependent and independent caspase-mediated apoptosis and androgen receptor (AR) antagonism have been described for bufalin at micromolar concentrations. Because a human pharmacokinetic study indicated that single nanomolar bufalin was safely achievable in the peripheral circulation, we evaluated its cellular activity within range with the AR-positive and P53 wild-type human LNCaP prostate cancer cells in vitro. Our data show that bufalin induced caspase-mediated apoptosis at 20 nmol/L or higher concentration with concomitant suppression of AR protein and its best-known target, PSA and steroid receptor coactivator 1 and 3 (SRC-1, SRC-3). Bufalin exposure induced protein abundance of P53 (not mRNA) and P21CIP1 (CDKN1A), G2 arrest, and increased senescence-like phenotype (SA-galactosidase). Small RNAi knocking down of P53 attenuated bufalin-induced senescence, whereas knocking down of P21CIP1 exacerbated bufalin-induced caspase-mediated apoptosis. In vivo, daily intraperitoneal injection of bufalin (1.5 mg/kg body weight) for 9 weeks delayed LNCaP subcutaneous xenograft tumor growth in NSG SCID mice with a 67% decrease of final weight without affecting body weight. Tumors from bufalin-treated mice exhibited increased phospho-P53 and SA-galactosidase without detectable caspase-mediated apoptosis or suppression of AR and PSA. Our data suggest potential applications of bufalin in therapy of prostate cancer in patients or chemo-interception of prostate precancerous lesions, engaging a selective activation of P53 senescence. Mol Cancer Ther; 17(11); 2341–52. ©2018 AACR.
Data from GnRH-R–Targeted Lytic Peptide Sensitizes BRCA Wild-type Ovarian Cancer to PARP Inhibition
Authors: Ma Shaolin , Pradeep Sunila , Villar-Prados Alejandro , Wen Yunfei , Bayraktar Emine , Mangala Lingegowda S. , Kim Mark Seungwook , Wu Sherry Y. , Hu Wei , Rodriguez-Aguayo Cristian , Leuschner Carola , Liang Xiaoyan , Ram Prahlad T. , Schlacher Katharina , Coleman Robert L. , Sood Anil K.
Published: April 2023

Abstract
EP-100 is a synthetic lytic peptide that specifically targets the gonadotropin-releasing hormone receptor on cancer cells. To extend the utility of EP-100, we aimed to identify effective combination therapies with EP-100 for ovarian cancer and explore potential mechanisms of this combination. A series of in vitro (MTT assay, immunoblot analysis, reverse-phase protein array, comet assay, and immunofluorescence staining) and in vivo experiments were carried out to determine the biological effects of EP-100 alone and in combination with standard-of-care drugs. EP-100 decreased the viability of ovarian cancer cells and reduced tumor growth in orthotopic mouse models. Of five standard drugs tested (cisplatin, paclitaxel, doxorubicin, topotecan, and olaparib), we found that the combination of EP-100 and olaparib was synergistic in ovarian cancer cell lines. Further experiments revealed that combined treatment of EP-100 and olaparib significantly increased the number of nuclear foci of phosphorylated histone H2AX. In addition, the extent of DNA damage was significantly increased after treatment with EP-100 and olaparib in comet assay. We performed reverse-phase protein array analyses and identified that the PI3K/AKT pathway was inhibited by EP-100, which we validated with in vitro experiments. In vivo experiment using the HeyA8 mouse model demonstrated that mice treated with EP-100 and olaparib had lower tumor weights (0.06 ± 0.13 g) than those treated with a vehicle (1.19 ± 1.09 g), EP-100 alone (0.62 ± 0.78 g), or olaparib alone (0.50 ± 0.63 g). Our findings indicate that combining EP-100 with olaparib is a promising therapeutic strategy for ovarian cancer.
Data from A Novel YAP1 Inhibitor Targets CSC-Enriched Radiation-Resistant Cells and Exerts Strong Antitumor Activity in Esophageal Adenocarcinoma
Authors: Song Shumei , Xie Min , Scott Ailing W. , Jin Jiankang , Ma Lang , Dong Xiaochuan , Skinner Heath D. , Johnson Randy L. , Ding Sheng , Ajani Jaffer A.
Published: April 2023

Abstract
Mounting evidence suggests that the Hippo coactivator Yes-associated protein 1 (YAP1) is a major mediator of cancer stem cell (CSC) properties, tumor progression, and therapy resistance as well as often a terminal node of many oncogenic pathways. Thus, targeting YAP1 may be a novel therapeutic strategy for many types of tumors with high YAP1 expression, including esophageal adenocarcinoma. However, effective YAP1 inhibitors are currently lacking. Here, we identify a small molecule (CA3) that not only has remarkable inhibitory activity on YAP1/Tead transcriptional activity but also demonstrates strong inhibitory effects on esophageal adenocarcinoma cell growth especially on YAP1 high–expressing esophageal adenocarcinoma cells both in vitro and in vivo. Remarkably, radiation-resistant cells acquire strong cancer stem cell (CSC) properties and aggressive phenotype, while CA3 can effectively suppress these phenotypes by inhibiting proliferation, inducing apoptosis, reducing tumor sphere formation, and reducing the fraction of ALDH1+ cells. Furthermore, CA3, combined with 5-FU, synergistically inhibits esophageal adenocarcinoma cell growth especially in YAP1 high esophageal adenocarcinoma cells. Taken together, these findings demonstrated that CA3 represents a new inhibitor of YAP1 and primarily targets YAP1 high and therapy-resistant esophageal adenocarcinoma cells endowed with CSC properties. Mol Cancer Ther; 17(2); 443–54. ©2017 AACR.
Data from Targeting Polo-like Kinase 1 by a Novel Pyrrole-Imidazole Polyamide–Hoechst Conjugate Suppresses Tumor Growth In Vivo
Authors: Liu Ke , Fang Lijing , Sun Haiyan , Pan Zhengyin , Zhang Jianchao , Chen Juntao , Shao Ximing , Wang Wei , Tan Yuanyan , Ding Zhihao , Ao Lijiao , Wu Chunlei , Liu Xiaoqi , Li Huashun , Wang Rui , Su Wu , Li Hongchang
Published: April 2023

Abstract
The serine/threonine kinase Polo-like kinase 1 (Plk1) plays a pivotal role in cell proliferation and has been validated as a promising anticancer drug target. However, very limited success has been achieved in clinical applications using existing Plk1 inhibitors, due to lack of sufficient specificity toward Plk1. To develop a novel Plk1 inhibitor with high selectivity and efficacy, we designed and synthesized a pyrrole-imidazole polyamide–Hoechst conjugate, PIP3, targeted to specific DNA sequence in the PLK1 promoter. PIP3 could specifically inhibit the cell cycle–regulated Plk1 expression and consequently retard tumor cell growth. Cancer cells treated with PIP3 exhibited severe mitotic defects and increased apoptosis, whereas normal cells were not affected by PIP3 treatment. Furthermore, subcutaneous injection of PIP3 into mice bearing human cancer xenografts induced significant tumor growth suppression with low host toxicity. Therefore, PIP3 exhibits the potential as an effective agent for targeted cancer therapy. Mol Cancer Ther; 17(5); 988–1002. ©2018 AACR.
Data from Wnt/β-Catenin Pathway Activation Mediates Adaptive Resistance to BRAF Inhibition in Colorectal Cancer
Authors: Chen Guangming , Gao Chenxi , Gao Xuan , Zhang Dennis Han , Kuan Shih-Fan , Burns Timothy F. , Hu Jing
Published: April 2023

Abstract
One of the most encouraging developments in oncology has been the success of BRAF inhibitors in BRAF-mutant melanoma. However, in contrast to its striking efficacy in BRAF-mutant melanomas, BRAF inhibitor monotherapy is ineffective in BRAF-mutant colorectal cancer. Although many studies on BRAF inhibitor resistance in colorectal cancer have focused on mechanisms underlying the reactivation of the EGFR/RAS/RAF/MEK/ERK pathway, the current study focuses on identifying novel adaptive signaling mechanisms, a fresh angle on colorectal cancer resistance to BRAF inhibition. We found that treatment with BRAF inhibitors (both current and next-generation BRAF inhibitors) upregulated the Wnt/β-catenin pathway in BRAFV600E-mutant colorectal cancer cell lines through activating the cytoplasmic tyrosine kinase focal adhesion kinase (FAK). The results showed that FAK activation upon BRAF inhibitor treatment did not require EGFR or ERK1/2 activation, implying that BRAF inhibitor treatment-induced hyperactivation of Wnt signaling is “pathway reactivation”-independent. BRAF inhibition–induced Wnt pathway activation was further validated in preclinical models of BRAFV600E-mutant colorectal cancer, including cell line xenograft model and a patient-derived xenograft model. Combined inhibition of BRAF/Wnt pathways or BRAF/FAK pathways exerted strong synergistic antitumor effects in cell culture model and mouse xenograft model. Overall, the current study has identified activation of the Wnt/β-catenin pathway as a novel fundamental cause of colon cancer resistance to BRAF inhibition. Our results suggest that although complete vertical pathway blockade is pivotal for effective and durable control of BRAF-mutant colorectal cancer, cotargeting parallel adaptive signaling—the Wnt/β-catenin pathway—is also essential. Mol Cancer Ther; 17(4); 806–13. ©2017 AACR.
Data from COX-2/sEH Dual Inhibitor PTUPB Potentiates the Antitumor Efficacy of Cisplatin
Authors: Wang Fuli , Zhang Hongyong , Ma Ai-Hong , Yu Weimin , Zimmermann Maike , Yang Jun , Hwang Sung Hee , Zhu Daniel , Lin Tzu-yin , Malfatti Michael , Turteltaub Kenneth W. , Henderson Paul T. , Airhart Susan , Hammock Bruce D. , Yuan Jianlin , de Vere White Ralph W. , Pan Chong-Xian
Published: April 2023

Abstract
Cisplatin-based therapy is highly toxic, but moderately effective in most cancers. Concurrent inhibition of cyclooxygenase-2 (COX-2) and soluble epoxide hydrolase (sEH) results in antitumor activity and has organ-protective effects. The goal of this study was to determine the antitumor activity of PTUPB, an orally bioavailable COX-2/sEH dual inhibitor, in combination with cisplatin and gemcitabine (GC) therapy. NSG mice bearing bladder cancer patient-derived xenografts were treated with vehicle, PTUPB, cisplatin, GC, or combinations thereof. Mouse experiments were performed with two different PDX models. PTUPB potentiated cisplatin and GC therapy, resulting in significantly reduced tumor growth and prolonged survival. PTUPB plus cisplatin was no more toxic than cisplatin single-agent treatment as assessed by body weight, histochemical staining of major organs, blood counts, and chemistry. The combination of PTUPB and cisplatin increased apoptosis and decreased phosphorylation in the MAPK/ERK and PI3K/AKT/mTOR pathways compared with controls. PTUPB treatment did not alter platinum–DNA adduct levels, which is the most critical step in platinum-induced cell death. The in vitro study using the combination index method showed modest synergy between PTUPB and platinum agents only in 5637 cell line among several cell lines examined. However, PTUPB is very active in vivo by inhibiting angiogenesis. In conclusion, PTUPB potentiated the antitumor activity of cisplatin-based treatment without increasing toxicity in vivo and has potential for further development as a combination chemotherapy partner. Mol Cancer Ther; 17(2); 474–83. ©2017 AACR.
Data from Acquired Resistance to FGFR Inhibitor in Diffuse-Type Gastric Cancer through an AKT-Independent PKC-Mediated Phosphorylation of GSK3β
Authors: Lau Wen Min , Teng Eileen , Huang Kie Kyon , Tan Jin Wei , Das Kakoli , Zang Zhijiang , Chia Tania , Teh Ming , Kono Koji , Yong Wei Peng , Shabbir Asim , Tay Amy , Phua Niam Sin , Tan Patrick , Chan Shing Leng , So Jimmy Bok Yan
Published: April 2023

Abstract
Preclinical models of diffuse-type gastric cancer (DGC) that reliably predict clinical activity of novel compounds are lacking. To overcome the problem of poor tumor cellularity in DGC, we used cells from malignant ascites to establish DGC patient-derived xenograft (PDX) models that recapitulate the primary cancer. Cells in PDX model GAGA6 with FGFR2 amplification were sensitive to AZD4547, a potent FGFR inhibitor that is being clinically evaluated for FGFR-aberrant cancer types. Intermittent in vivo treatment of GAGA6 tumors with AZD4547 gave rise to PDX tumors with acquired resistance to AZD4547, GAGA6-R. Surprisingly, there were no mutations in the FGFR2 gene in GAGA6-R, negating gatekeeper mutations as a mechanism of drug resistance. Phosphorylation of FGFR2 and downstream signaling molecules AKT/PKB and MAPK/ERK remained inhibited by AZD4547. Further analysis of signaling pathways identified AKT-independent phosphorylation and inhibition of GSK3β as a mechanism of drug resistance in GAGA6-R cells. Treatment of GAGA6-R cells with protein kinase C (PKC) inhibitor H7 in combination with AZD4547 led to dephosphorylation and activation of GSK3β with concomitant downregulation of MCL-1 and BCL-XL. Combined treatment with AZD4547 and H7 in vitro synergistically enhanced cell death in GAGA6-R but not GAGA6 cells. Furthermore, midostaurin, a multikinase inhibitor with PKC-inhibiting activity, in part reversed resistance of GAGA6-R tumor to AZD4547 in vivo. Our results suggest that upon challenge with FGFR inhibitors, FGFR2-amplified tumors that are highly dependent on FGFR2 signaling for survival rapidly develop resistance by switching to a PKC-mediated inhibition of GSK3β to gain a survival advantage. Mol Cancer Ther; 17(1); 232–42. ©2017 AACR.
Data from Combinatorial Therapy of Zinc Metallochaperones with Mutant p53 Reactivation and Diminished Copper Binding
Authors: Zaman Saif , Yu Xin , Bencivenga Anthony F. , Blanden Adam R. , Liu Yue , Withers Tracy , Na Bing , Blayney Alan J. , Gilleran John , Boothman David A. , Loh Stewart N. , Kimball S. David , Carpizo Darren R.
Published: April 2023

Abstract
Chemotherapy and radiation are more effective in wild-type (WT) p53 tumors due to p53 activation. This is one rationale for developing drugs that reactivate mutant p53 to synergize with chemotherapy and radiation. Zinc metallochaperones (ZMC) are a new class of mutant p53 reactivators that restore WT structure and function to zinc-deficient p53 mutants. We hypothesized that the thiosemicarbazone, ZMC1, would synergize with chemotherapy and radiation. Surprisingly, this was not found. We explored the mechanism of this and found the reactive oxygen species (ROS) activity of ZMC1 negates the signal on p53 that is generated with chemotherapy and radiation. We hypothesized that a zinc scaffold generating less ROS would synergize with chemotherapy and radiation. The ROS effect of ZMC1 is generated by its chelation of redox active copper. ZMC1 copper binding (KCu) studies reveal its affinity for copper is approximately 108 greater than Zn2+. We identified an alternative zinc scaffold (nitrilotriacetic acid) and synthesized derivatives to improve cell permeability. These compounds bind zinc in the same range as ZMC1 but bound copper much less avidly (106- to 107-fold lower) and induced less ROS. These compounds were synergistic with chemotherapy and radiation by inducing p53 signaling events on mutant p53. We explored other combinations with ZMC1 based on its mechanism of action and demonstrate that ZMC1 is synergistic with MDM2 antagonists, BCL2 antagonists, and molecules that deplete cellular reducing agents. We have identified an optimal Cu2+:Zn2+ binding ratio to facilitate development of ZMCs as chemotherapy and radiation sensitizers. Although ZMC1 is not synergistic with chemotherapy and radiation, it is synergistic with a number of other targeted agents.
Data from Risk of Pneumonitis Associated with Programmed Cell Death 1 Inhibitors in Cancer Patients: A Meta-analysis
Authors: Zhang Sheng , Liang Fei , Zhu Ji , Chen Qiang
Published: April 2023

Abstract
Pneumonitis, a rare but potentially life-threatening adverse event in cancer patients receiving programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1) inhibitors, has been reported in case reports, clinical trials, and retrospective studies. We performed a systematic review and meta-analysis to calculate the RR of pneumonitis associated with the use of PD-1/L1 inhibitors in randomized clinical trials (RCT). We searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, trial registers, conference proceedings, review articles, and reference lists of trial publications for all relevant RCTs comparing PD-1/L1 inhibitors to control with available data on pneumonitis. The pooled incidence, RR, and 95% confidence intervals (CI) were calculated using fixed effects or random effects model according to the heterogeneity of included trials. Twelve RCTs were eligible for the meta-analysis, yielding a total of 5,775 patients included in trials evaluating a PD-1 inhibitor; no eligible trials evaluated a PD-L1 inhibitor. The pooled incidence of all-grade pneumonitis for patients treated with PD-1 inhibitors was 3.2% (95% CI, 2.3–4.5), and that of high-grade pneumonitis was 1.1% (95% CI, 0.7–1.7). The RR of all-grade and high-grade pneumonitis was 4.36 (95% CI, 2.58–7.38) and 2.86 (95% CI, 1.30–6.31), respectively. In a sensitivity analysis, PD-1 inhibitors were also associated with significantly increased risk of pneumonitis per person-month (for all grade, RR = 3.37; 95% CI, 1.97–5.76; for high grade, RR = 2.25; 95% CI, 1.03–4.94). PD-1 inhibitors were associated with a significant increase of all-grade and high-grade pneumonitis both per treatment episode and per person-month. Mol Cancer Ther; 16(8); 1588–95. ©2017 AACR.
Data from Necuparanib, A Multitargeting Heparan Sulfate Mimetic, Targets Tumor and Stromal Compartments in Pancreatic Cancer
Authors: MacDonald Amanda , Priess Michelle , Curran Jennifer , Guess Jamey , Farutin Victor , Oosterom Ilse , Chu Chia Lin , Cochran Edward , Zhang Lynn , Getchell Kristen , Lolkema Martijn , Schultes Birgit C. , Krause Silva
Published: April 2023

Abstract
Pancreatic cancer has an abysmal 5-year survival rate of 8%, making it a deadly disease with a need for novel therapies. Here we describe a multitargeting heparin-based mimetic, necuparanib, and its antitumor activity in both in vitro and in vivo models of pancreatic cancer. Necuparanib reduced tumor cell proliferation and invasion in a three-dimensional (3D) culture model; in vivo, it extended survival and reduced metastasis. Furthermore, proteomic analysis demonstrated that necuparanib altered the expression levels of multiple proteins involved in cancer-driving pathways including organ development, angiogenesis, proliferation, genomic stability, cellular energetics, and invasion and metastasis. One protein family known to be involved in invasion and metastasis and altered by necuparanib treatment was the matrix metalloprotease (MMP) family. Necuparanib reduced metalloproteinase 1 (MMP1) and increased tissue inhibitor of metalloproteinase 3 (TIMP3) protein levels and was found to increase RNA expression of TIMP3. MMP enzymatic activity was also found to be reduced in the 3D model. Finally, we confirmed necuparanib's in vivo activity by analyzing plasma samples of patients enrolled in a phase I/II study in patients with metastatic pancreatic cancer; treatment with necuparanib plus standard of care significantly increased TIMP3 plasma protein levels. Together, these results demonstrate necuparanib acts as a broad multitargeting therapeutic with in vitro and in vivo anti-invasive and antimetastatic activity.
Data from The Increased Expression of Estrogen-Related Receptor α Correlates with Wnt5a and Poor Prognosis in Patients with Glioma
Authors: Zhang Liudi , Zhu Yingfeng , Cheng Haixia , Zhang Jinsen , Zhu Yuqian , Chen Haifei , Chen Lu , Qi Huijie , Ren Guoqiang , Tang Jianmin , Zhong Mingkang , Hua Wei , Shi Xiaojin , Li Qunyi
Published: April 2023

Abstract
Malignant glioma is an often fatal type of cancer. Elevated expression of the orphan nuclear receptor estrogen-related receptor alpha (ERRα) is an unfavorable factor for malignant progression and poor prognosis in several cancers, although the mechanism by which this receptor affects the pathophysiology of cancers remains obscure. However, few studies have been conducted in regard to the role of ERRα in glioma. In the current study, we found that elevated expression of ERRα was observed in 107 glioma cases by means of IHC. Clinically, high expression of ERRα was associated with later stages of disease progression and clinical outcome of patients with glioma. ERRα had the ability to promote cell proliferation and migration in glioma cell lines. Moreover, in a xenograft model, we also found that silencing ERRα had an inhibitory effect on the growth of glioma. Further investigation confirmed that ERRα was involved in the carcinogenesis of glioma via the regulation of the Wnt5a signal pathway in vitro and in vivo. Our study was first to show the overexpression of ERRα in glioma tissues and a direct correlation between ERRα expression and clinical prognosis of glioma. Together, these data reveal that ERRα has prognostic significance in glioma, and targeting ERRα may provide a reliable therapeutic strategy for the treatment for human glioma.
Data from Phosphodiesterase 3A Represents a Therapeutic Target that Drives Stem Cell–like Property and Metastasis in Breast Cancer
Authors: Hao Na , Shen Wenzhi , Du Renle , Jiang Shan , Zhu Junyong , Chen Yanan , Huang Chongbiao , Shi Yi , Xiang Rong , Luo Yunping
Published: April 2023

Abstract
Considerable evidence suggests that as breast cancer progresses, genetic and epigenetic mechanisms contribute to the emergence of self-renewing cells (CSC), which may also arise as a consequence of metastasis. Although the molecular pathways that trigger stemness and metastasis are known, key molecular and mechanistic gaps in our understanding of these processes remain unclear. Here, we first screened the inflammation-associated stemness gene phosphodiesterase 3A (PDE3A) using a medium-throughput siRNA library, which was overexpressed in breast tumors and significantly correlated with clinical progression. PDE3A induced the inflammatory nuclear factor NFκB signaling pathway by suppressing cAMP/PKA, which promotes the expression of the stem cell marker OCT4. In addition, PDE3A also promoted the translocation of CCDC88A from the cytoplasm to nuclei, thereby boosting the invasion–metastasis cascade in breast cancer. Most importantly, the PDE3A-selective inhibitor cilostazol dramatically suppressed breast tumor growth and reduced metastasis to the lungs in xenograft breast cancer models, with minimum toxicity. Taken together, we show that PDE3A could predispose patients with breast cancer to metastases by acting as a mediator of cancer stemness. PDE3A is a potential therapeutic target for advanced breast cancer.
Data from Impact of Chemical-Induced Mutational Load Increase on Immune Checkpoint Therapy in Poorly Responsive Murine Tumors
Authors: Kuczynski Elizabeth A. , Krueger Janna , Chow Annabelle , Xu Ping , Man Shan , Sundaravadanam Yogi , Miller Jessica K. , Krzyzanowski Paul M. , Kerbel Robert S.
Published: April 2023

Abstract
A recurring historic finding in cancer drug development is encouraging antitumor effects observed in tumor-bearing mice that fail to translate into the clinic. An intriguing exception to this pattern is immune checkpoint therapy, as the sustained tumor regressions observed in subsets of cancer patients are rare in mice. Reasoning that this may be due in part to relatively low mutational loads of mouse tumors, we mutagenized transplantable mouse tumor cell lines EMT-6/P, B16F1, RENCA, CT26, and MC38 in vitro with methylnitro-nitrosoguanidine (MNNG) or ethylmethane sulfonate (EMS) and tested their responsiveness to PD-L1 blockade. Exome sequencing confirmed an increase in somatic mutations by mutagen treatment, an effect mimicked in EMT-6 variants chronically exposed in vivo to cisplatin or cyclophosphamide. Certain mutagenized variants of B16F1, EMT-6/P, CT26, and MC38 (but not RENCA) were more immunogenic than their parents, yet anti-PD-L1 sensitization developed only in some EMT-6/P and B16F1 variants. Treatment response patterns corresponded with changes in immune cell infiltration and especially increases in CD8+ T cells. Chronically cisplatin-exposed EMT-6 variants were also more responsive to anti-PD-L1 therapy. Although tumor PD-L1 expression was upregulated in in vivo chemotherapy-exposed variants, PD-L1 expression levels were not consistently associated with anti-PD-L1 treatment activity across mutagenized or chemotherapy-exposed variants. In summary, mutagenized and more immunogenic mouse tumors were not universally sensitized to PD-L1 blockade. Chemically mutagenized variants may be useful to evaluate the impact of immunologically “hot” or “cold” tumors with a high mutational load, to which certain chemotherapy agents may contribute, on immunotherapy outcomes. Mol Cancer Ther; 17(4); 869–82. ©2018 AACR.
Data from Therapeutic Impact of Nanoparticle Therapy Targeting Tumor-Associated Macrophages
Authors: Penn Courtney A. , Yang Kun , Zong Hong , Lim Jae-Young , Cole Alex , Yang Dongli , Baker James , Goonewardena Sascha N. , Buckanovich Ronald J.
Published: April 2023

Abstract
Antiangiogenic therapies, despite initial encouragement, have demonstrated a limited benefit in ovarian cancer. Laboratory studies suggest antiangiogenic therapy–induced hypoxia can induce tumor “stemness” as resistance to antiangiogenic therapy develops and limits the therapeutic benefit. Resistance to antiangiogenic therapy and an induction of tumor stemness may be mediated by proangiogenic tumor-associated macrophages (TAM). As such, TAMs have been proposed as a therapeutic target. We demonstrate here that ovarian TAMs express high levels of the folate receptor-2 (FOLR2) and can be selectively targeted using G5-dendrimer nanoparticles using methotrexate as both a ligand and a toxin. G5-methotrexate (G5-MTX) nanoparticles deplete TAMs in both solid tumor and ascites models of ovarian cancer. As a therapeutic agent, these nanoparticles are more effective than cisplatin. Importantly, these nanoparticles could (i) overcome resistance to antiangiogenic therapy, (ii) prevent antiangiogenic therapy–induced increases in cancer stem–like cells in both murine and human tumor cell models, (iii) prevent antiangiogenic therapy–induced increases in VEGF-C, and (iv) prevent antiangiogenic therapy–induced BRCA1 gene expression. Combined, this work strongly supports the development of TAM-targeted nanoparticle therapy. Mol Cancer Ther; 17(1); 96–106. ©2017 AACR.
Data from Targeting Plk1 to Enhance Efficacy of Olaparib in Castration-Resistant Prostate Cancer
Authors: Li Jie , Wang Ruixin , Kong Yifan , Broman Meaghan M. , Carlock Colin , Chen Long , Li Zhiguo , Farah Elia , Ratliff Timothy L. , Liu Xiaoqi
Published: April 2023

Abstract
Olaparib is an FDA-approved PARP inhibitor (PARPi) that has shown promise as a synthetic lethal treatment approach for BRCA-mutant castration-resistant prostate cancer (CRPC) in clinical use. However, emerging data have also shown that even BRCA-mutant cells may be resistant to PARPi. The mechanistic basis for these drug resistances is poorly understood. Polo-like kinase 1 (Plk1), a critical regulator of many cell-cycle events, is significantly elevated upon castration of mice carrying xenograft prostate tumors. Herein, by combination with Plk1 inhibitor BI2536, we show a robust sensitization of olaparib in 22RV1, a BRCA1-deficient CRPC cell line, as well as in CRPC xenograft tumors. Mechanistically, monotherapy with olaparib results in an override of the G1–S checkpoint, leading to high expression of Plk1, which attenuates olaparib's overall efficacy. In BRCA1 wild-type C4-2 cells, Plk1 inhibition also significantly increases the efficacy of olaparib in the presence of p53 inhibitor. Collectively, our findings not only implicate the critical role of Plk1 in PARPi resistance in BRCA-mutant CRPC cells, but also shed new light on the treatment of non-BRCA–mutant patient subgroups who might also respond favorably to PARPi. Mol Cancer Ther; 16(3); 469–79. ©2017 AACR.
Data from Co-targeting Bulk Tumor and CSCs in Clinically Translatable TNBC Patient-Derived Xenografts via Combination Nanotherapy
Authors: Sulaiman Andrew , McGarry Sarah , El-Sahli Sara , Li Li , Chambers Jason , Phan Alexandra , Côté Marceline , Cron Greg O. , Alain Tommy , Le Yevgeniya , Lee Seung-Hwan , Liu Sheng , Figeys Daniel , Gadde Suresh , Wang Lisheng
Published: April 2023

Abstract
Triple-negative breast cancer (TNBC) accounts disproportionally for the majority of breast cancer–related deaths throughout the world. This is largely attributed to lack of a specific therapy capable of targeting both bulk tumor mass and cancer stem cells (CSC), as well as appropriate animal models to accurately evaluate treatment efficacy for clinical translation. Thus, development of effective and clinically translatable targeted therapies for TNBC is an unmet medical need. We developed a hybrid nanoparticles-based co-delivery platform containing both paclitaxel and verteporfin (PV-NP) to target TNBC patient-derived xenograft (PDX) tumor and CSCs. MRI and IVIS imaging were performed on mice containing PDX tumors to assess tumor vascularity and accumulation of NPs. NF-κB, Wnt, and YAP activities were measured by reporter assays. Mice bearing TNBC PDX tumor were treated with PV-NPs and controls, and tumors progression and CSC subpopulations were analyzed. MRI imaging indicated high vascularization of PDX tumors. IVIS imaging showed accumulation of NPs in PDX tumors. In comparison with control-NPs and free-drug combination, PV-NPs significantly retarded tumor growth of TNBC PDX. PV-NPs simultaneously repressed NF-κB, Wnt, and YAP that have been shown to be crucial for cancer growth, CSC development, and tumorigenesis. In conclusion, NPs containing two clinically used drugs concurrently inhibited NF-κB, Wnt, and YAP pathways and exhibited synergic effects on killing TNBC bulk tumor and CSCs. This combination nanotherapy evaluated with a PDX model may lead to an effective treatment of patients with TNBC.
Data from Preclinical Efficacy and Safety Comparison of CD3 Bispecific and ADC Modalities Targeting BCMA for the Treatment of Multiple Myeloma
Authors: Panowski Siler H. , Kuo Tracy C. , Zhang Yi , Chen Amy , Geng Tao , Aschenbrenner Laura , Kamperschroer Cris , Pascua Edward , Chen Wei , Delaria Kathy , Farias Santiago , Bateman Marjorie , Dushin Russell G. , Chin Sherman M. , Van Blarcom Thomas J. , Yeung Yik Andy , Lindquist Kevin C. , Chunyk Allison G. , Kuang Bing , Han Bora , Mirsky Michael , Pardo Ingrid , Buetow Bernard , Martin Thomas G. , Wolf Jeffrey L. , Shelton David , Rajpal Arvind , Strop Pavel , Chaparro-Riggers Javier , Sasu Barbra J.
Published: April 2023

Abstract
The restricted expression pattern of B-cell maturation antigen (BCMA) makes it an ideal tumor-associated antigen (TAA) for the treatment of myeloma. BCMA has been targeted by both CD3 bispecific antibody and antibody–drug conjugate (ADC) modalities, but a true comparison of modalities has yet to be performed. Here we utilized a single BCMA antibody to develop and characterize both a CD3 bispecific and 2 ADC formats (cleavable and noncleavable) and compared activity both in vitro and in vivo with the aim of generating an optimal therapeutic. Antibody affinity, but not epitope was influential in drug activity and hence a high-affinity BCMA antibody was selected. Both the bispecific and ADCs were potent in vitro and in vivo, causing dose-dependent cell killing of myeloma cell lines and tumor regression in orthotopic myeloma xenograft models. Primary patient cells were effectively lysed by both CD3 bispecific and ADCs, with the bispecific demonstrating improved potency, maximal cell killing, and consistency across patients. Safety was evaluated in cynomolgus monkey toxicity studies and both modalities were active based on on-target elimination of B lineage cells. Distinct nonclinical toxicity profiles were seen for the bispecific and ADC modalities. When taken together, results from this comparison of BCMA CD3 bispecific and ADC modalities suggest better efficacy and an improved toxicity profile might be achieved with the bispecific modality. This led to the advancement of a bispecific candidate into phase I clinical trials.
Data from Inhibition of AKT Sensitizes Cancer Cells to Antineoplastic Drugs by Downregulating Flap Endonuclease 1
Authors: Zhu Hong , Wu Congye , Wu Ting , Xia Wen , Ci Shusheng , He Weiru , Zhang Yilan , Li Lulu , Zhou Shiying , Zhang Jing , Edick Ashlin M. , Zhang Anna , Pan Fei-Yan , Hu Zhigang , He Lingfeng , Guo Zhigang
Published: April 2023

Abstract
DNA repair mechanisms are crucial for cell survival. It increases the cancer cell's ability to resist DNA damage. FEN1 is involved in DNA replication and repair, specifically long-patch base excision repair. Although the gene function and post-translational modification of FEN1 are well studied, the regulatory mechanism of FEN1 by upstream signal pathways remains unclear. In this article, we have identified AKT as a regulator of FEN1 activity in lung cancer cells. Sustained activation of AKT can phosphorylate nuclear transcription factor NF-κB/p65. NF-κB/p65 directly binds to FEN1 promoter to promote a high transcription level of FEN1, revealing the contribution of the AKT signaling pathway to drug resistance of cancer cells. The combination of an AKT inhibitor and cisplatin efficiently suppressed lung cancer cell growth both in vitro and in vivo. Our study illustrated an upstream regulatory mechanism of FEN1, which will contribute to the development of effective lung cancer therapies.

These findings identified AKT as a regulator of FEN1 activity and revealed the AKT signaling pathway's contribution to drug resistance, which will contribute to the development of effective lung cancer therapy.
Data from Cooperative Effect of Oncogenic MET and PIK3CA in an HGF-Dominant Environment in Breast Cancer
Authors: Liu Shuying , Li Shunqiang , Wang Bailiang , Liu Wenbin , Gagea Mihai , Chen Huiqin , Sohn Joohyuk , Parinyanitikul Napa , Primeau Tina , Do Kim-Anh , Vande Woude George F. , Mendelsohn John , Ueno Naoto T. , Mills Gordon B. , Tripathy Debu , Gonzalez-Angulo Ana M.
Published: April 2023

Abstract
There is compelling evidence that oncogenic MET and PIK3CA signaling pathways contribute to breast cancer. However, the activity of pharmacologic targeting of either pathway is modest. Mechanisms of resistance to these monotherapies have not been clarified. Currently, commonly used mouse models are inadequate for studying the HGF–MET axis because mouse HGF does not bind human MET. We established human HGF–MET paired mouse models. In this study, we evaluated the cooperative effects of MET and PIK3CA in an environment with involvement of human HGF in vivo. Oncogenic MET/PIK3CA synergistically induced aggressive behavior and resistance to each targeted therapy in an HGF-paracrine environment. Combined targeting of MET and PI3K abrogates resistance. Associated cell signaling changes were explored by functional proteomics. Consistently, combined targeting of MET and PI3K inhibited activation of associated oncogenic pathways. We also evaluated the response of tumor cells to HGF stimulation using breast cancer patient-derived xenografts (PDX). HGF stimulation induced significant phosphorylation of MET for all PDX lines detected to varying degrees. However, the levels of phosphorylated MET are not correlated with its expression, suggesting that MET expression level cannot be used as a sole criterion to recruit patients to clinical trials for MET-targeted therapy. Altogether, our data suggest that combined targeting of MET and PI3K could be a potential clinical strategy for breast cancer patients, where phosphorylated MET and PIK3CA mutation status would be biomarkers for selecting patients who are most likely to derive benefit from these cotargeted therapy.
Data from Relative Target Affinities of T-Cell–Dependent Bispecific Antibodies Determine Biodistribution in a Solid Tumor Mouse Model
Authors: Mandikian Danielle , Takahashi Nene , Lo Amy A. , Li Ji , Eastham-Anderson Jeffrey , Slaga Dionysos , Ho Jason , Hristopoulos Maria , Clark Robyn , Totpal Klara , Lin Kedan , Joseph Sean B. , Dennis Mark S. , Prabhu Saileta , Junttila Teemu T. , Boswell C. Andrew
Published: April 2023

Abstract
Anti-HER2/CD3, a T-cell–dependent bispecific antibody (TDB) construct, induces T-cell–mediated cell death in cancer cells expressing HER2 by cross-linking tumor HER2 with CD3 on cytotoxic T cells, thereby creating a functional cytolytic synapse. TDB design is a very challenging process that requires consideration of multiple parameters. Although therapeutic antibody design strategy is commonly driven by striving for the highest attainable antigen-binding affinity, little is known about how the affinity of each TDB arm can affect the targeting ability of the other arm and the consequent distribution and efficacy. To our knowledge, no distribution studies have been published using preclinical models wherein the T-cell–targeting arm of the TDB is actively bound to T cells. We used a combined approach involving radiochemistry, invasive biodistribution, and noninvasive single-photon emission tomographic (SPECT) imaging to measure TDB distribution and catabolism in transgenic mice with human CD3ϵ expression on T cells. Using CD3 affinity variants, we assessed the impact of CD3 affinity on short-term pharmacokinetics, tissue distribution, and cellular uptake. Our experimental approach determined the relative effects of (i) CD3 targeting to normal tissues, (ii) HER2 targeting to HER2-expressing tumors, and (iii) relative HER2/CD3 affinity, all as critical drivers for TDB distribution. We observed a strong correlation between CD3 affinity and distribution to T-cell–rich tissues, with higher CD3 affinity reducing systemic exposure and shifting TDB distribution away from tumor to T-cell–containing tissues. These observations have important implications for clinical translation of bispecific antibodies for cancer immunotherapy. Mol Cancer Ther; 17(4); 776–85. ©2018 AACR.
Data from Therapeutic Inhibition of the Receptor Tyrosine Kinase AXL Improves Sensitivity to Platinum and Taxane in Ovarian Cancer
Authors: Quinn Jeanne M. , Greenwade Molly M. , Palisoul Marguerite L. , Opara Gregory , Massad Katina , Guo Lei , Zhao Peinan , Beck-Noia Hollie , Hagemann Ian S. , Hagemann Andrea R. , McCourt Carolyn K. , Thaker Premal H. , Powell Matthew A. , Mutch David G. , Fuh Katherine C.
Published: April 2023

Abstract
Ovarian cancer, one of the deadliest malignancies in female cancer patients, is characterized by recurrence and poor response to cytotoxic chemotherapies. Fewer than 30% of patients with resistant disease will respond to additional chemotherapy treatments. This study aims to determine whether and how inhibition of the receptor tyrosine kinase AXL can restore sensitivity to first-line platinum and taxane therapy in ovarian cancer. AXL staining was quantified in a patient tissue microarray and correlated with chemoresponse of patients. We used small hairpin RNAs to knock down AXL expression and the small-molecule inhibitor BGB324 to inhibit AXL and assessed sensitivity of cell lines and primary patient-derived cells to chemotherapy. We quantified platinum accumulation by inductivity-coupled plasma phase mass spectrometry. Finally, we treated chemoresistant patient-derived xenografts with chemotherapy, BGB324, or chemotherapy plus BGB324 and monitored tumor burden. AXL expression was higher in chemoresistant patient tumors and cell lines than in chemosensitive tumors and cell lines. AXL staining significantly predicted chemoresponse. Knockdown and inhibition of AXL dose-dependently improved response to paclitaxel and carboplatin in both cell lines and primary cells. AXL inhibition increased platinum accumulation by 2-fold (*, P < 0.05). In vivo studies indicated that AXL inhibition enhanced the ability of chemotherapy to prevent tumor growth (****, P < 0.0001). AXL contributes to platinum and taxane resistance in ovarian cancer, and inhibition of AXL improves chemoresponse and accumulation of chemotherapy drugs. This study supports continued investigation into AXL as a clinical target.
Abstract 1129: Targeting tissue-resident macrophage progenitors restores anti-tumor immunity and suppresses tumor growth
Authors: Chen Hui , Paradise Marc , Shepard Ryan , Wang Guangfang , Onaitis Mark , Varner Judith
Published: April 2023

Macrophages are innate immune cells that accumulate rapidly in tumors, where they promote immune suppression, tumor growth and resistance to checkpoint inhibitor therapy. As these cells play critical roles in tumor progression, they are the focus of efforts to develop novel cancer therapeutics. Strategies to inhibit macrophage accumulation to suppress tumor growth by blocking their recruitment from circulation have been only partially effective. In this project, we examined the origins of tumor associated macrophages using lineage tracing, flow cytometry, and single cell sequencing. We found that large proportions of macrophages in subcutaneous and genetically engineered mouse tumors do not derive from Ly6C+ or Ly6C- or CCR2+ monocytes. Instead, a large population of CCR2-Ly6C-F4/80hi macrophages that are CD206+MerTK+ are profoundly immune suppressive resident macrophages that arise from a transcriptionally related proliferative progenitor subpopulation rather than by trafficking from the circulation. By comparing gene expression profiles of resident and recruited macrophages in subcutaneous, alveolar, central nervous and renal normal and tumor tissues, we identified generic tissue resident macrophage and recruited signatures that reveal that resident macrophages are more immune suppressive than recruited macrophages and are associated with worse outcomes in cancer patients. Tissue resident macrophages express signatures of Myc-driven proliferation, cholesterol metabolism and profound immune suppression while bone marrow derived macrophages express mixed signatures of inflammation and immune suppression. Genetic and pharmacological inhibition of c-Kit/mCsf1R, cMyc and cyclin-dependent kinases suppressed the expansion of these macrophages, thereby limiting their accumulation in tumors, promoting anti-tumor adaptive immunity and inhibiting tumor progression in mouse models of cancer. We identified a novel cKit/Csf1r/Cdk19 inhibitor that suppressed tissue resident macrophage accumulation and potently inhibited tumor growth.

These results identify tissue resident macrophage progenitor cells as key targets for the development of therapeutic strategies to stimulate anti-cancer immunity.

Citation Format: Hui Chen, Marc Paradise, Ryan Shepard, Guangfang Wang, Mark Onaitis, Judith Varner. Targeting tissue-resident macrophage progenitors restores anti-tumor immunity and suppresses tumor growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1129.
Abstract 1237: Zeb1-mediated autophagy enhances resistance of breast cancer cells to genotoxic drugs
Authors: Barlev Nick A. , Fedorova Olga , Daks Alexandra , Tulchinsky Eugene M.
Published: April 2023

This report presents novel results on the involvement of epithelial to mesenchymal transition (EMT) in the process of autophagy. Autophagy is a highly conserved process of cellular self-digestion that involves the formation of autophagosomes for the delivery of intracellular components and dysfunctional organelles to lysosomes. This process is induced by different signals including starvation, mitochondrial dysfunction, and DNA damage. The molecular link between autophagy and DNA damage is not well understood yet. Importantly, tumor cells utilize the mechanism of autophagy to cope with genotoxic anti-cancer drug therapy. Another mechanism of drug resistance is provided to cancer cells via the execution of the EMT program. One of the critical transcription factors of EMT is Zeb1. Here we demonstrate that Zeb1 is involved in the regulation of autophagy in several breast cancer cell models. On the molecular level, forced expression of Zeb1 in otherwise epithelial cells likely facilitates autophagy through the regulation of several autophagic genes, resulting in increased LC3-II levels, augmented staining with Lysotracker, and increased resistance to genotoxic drugs. On the contrary, the attenuation of Zeb1 expression in TNBC cells led to the opposite effect. Consequently, we propose that Zeb1 augments the resistance of breast cancer cells to genotoxic drugs, at least partially, by promoting autophagy. Collectively, we have uncovered a novel function of Zeb1 in the regulation of autophagy in breast cancer cells.

Citation Format: Nick A. Barlev, Olga Fedorova, Alexandra Daks, Eugene M. Tulchinsky. Zeb1-mediated autophagy enhances resistance of breast cancer cells to genotoxic drugs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1237.