bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1230: Critical role of cav1 in high-throughput identification of gallic acid as a novel late-stage autophagy suppresser against invasive breast cancer
Authors: Wang Neng , Zhang Fengxue , Wang Zhiyu , Zheng Yifeng , Wang Shengqi , Yang Bowen 
Published: September 2020

Abstract
Purpose: Development of autophagy inhibitors has important clinical significance in cancer therapies. We and others demonstrated that over-expression of Caveolin-1 (Cav1), which was the major scaffolding protein of caveolae, was associated with higher tumor stage, metastasis and worse prognosis in various carcinomas, particularly in breast cancer. Furthermore, we identified critical role of Cav1 in breast cancer metastasis via modulation of lysosomal function and autophagy. Based on the above, we screened a series of 2, 645 kinds of small-molecule drugs to find out certain cav1 inhibitors which could suppress autophagy and breast cancer metastasis.
Experimental Design: We conducted the 1st high-throughput screening based on surface plasmon resonance (SPR) analysis of cav-1 interaction with 2, 645 kinds of small-molecule drugs. Secondly, we launched the 2nd high-throughput screening based on CCK8 analysis to validate the anti-cancer potential of the selected compounds. We also carried out the final high-throughput screening to investigate their autophagic effects with high content image cytometry assay. The anti-cancer and anti-metastasis effects of the final drug candidate was investigated using invasive breast cancer cells MDA-MB-231 and BT-549, and its role on autophagy was further investigated by transfection of mRFP-GFP-LC3 adenoviral vector and western blot analysis of autophagic proteins.
Results: 2, 645 kinds of small-molecule drugs were screened based on a series of high-throughput screening. The compound gallic acid was identified as the candidate drug owing to its strong interaction and competitive inhibition with cav1, its potent anti-proliferation potential on both invasive breast cancer cells MDA-MB-231 and BT-549, as well as its potent autophagic inhibition compared with the other 2, 644 drugs. Further experimental validation revealed that gallic acid was a potent late-stage autophagy inhibitor via inhibiting autophagosome-lysosome fusion.
Conclusions: Collectively, these results demonstrated that the cav1 inhibitor gallic acid was a novel late-stage autophagy suppressor with potential clinical application for invasive breast cancer therapy.
Citation Format: Neng Wang, Fengxue Zhang, Zhiyu Wang, Yifeng Zheng, Shengqi Wang, Bowen Yang. Critical role of cav1 in high-throughput identification of gallic acid as a novel late-stage autophagy suppresser against invasive breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1230.
Abstract 1231: Targeting JNK1/2 induces a potent cytostatic response in estrogen receptor expressing breast cancer cells, with induction of autophagy and senescence as measurable outcomes
Authors: Herrington Kyler , Joseph Carol , Abdulmoneim Samar , Lewis Allison , Cai Jingwen , Youngblood Hannah , Liu Yutao , Schoenlein Patricia 
Published: September 2020

Abstract
The c-Jun N-terminal kinases, JNK1/2 are members of the mitogen activated protein kinase (MAPK) family that can mediate inflammatory responses, cell differentiation, cell proliferation, and/or cell death. In breast cancer, JNK signaling has been associated with increased proliferation, angiogenesis, and tumor metastasis. Also, inhibition of JNK has been shown to promote tumor cytostasis, but this inhibition also attenuates the cytotoxic effects of certain chemotherapeutics, calling into question the therapeutic potential of JNK inhibitors. In this study, we hypothesized that JNK1/2 inhibition induced autophagy, as a mechanism of protection against chemotherapy- and endocrine-induced apoptosis. Autophagy is a normal physiologic process required for the elimination of damaged mitochondria and misfolded proteins that can be induced in cancer cells under certain stresses such as hypoxia and drug insult to provide protection from death. To characterize the role of JNK1/2 in autophagy, we utilized two ERα expressing human breast cancer cell lines, T47-D and MCF-7. Autophagy flux experiments were performed in which the steady state levels of the autophagy protein LC3 II were analyzed in control cells versus cells undergoing JNK1/2 inhibition with the non-reversible JNK-IN8 inhibitor. JNK-IN8 was used as a single agent or in combination with estradiol and/or antiestrogen treatment. These studies reproducibly identified JNK1/2 inhibition as a mechanism of autophagy activation. The induction of autophagy correlated with sustained inhibition of proliferation as determined by cell counts, MTT, and clonogenic assays, and induction of senescence (in T47-D cells) as determined by the expression of β-galactosidase. In contrast, induction of apoptosis was not a major outcome of JNK1/2 inhibition. These pre-clinical studies provide strong evidence that JNK1/2 is an attractive molecular target to improve the treatment of endocrine responsive breast cancer, but they also emphasize that cells are surviving by autophagy and/or senescence. Because cell survival by autophagy and/or senescence could ultimately lead to breast cancer relapse, ongoing studies are addressing approaches to effectively kill these surviving cell populations.
Citation Format: Kyler Herrington, Carol Joseph, Samar Abdulmoneim, Allison Lewis, Jingwen Cai, Hannah Youngblood, Yutao Liu, Patricia Schoenlein. Targeting JNK1/2 induces a potent cytostatic response in estrogen receptor expressing breast cancer cells, with induction of autophagy and senescence as measurable outcomes [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1231.
Abstract 1236: In vitro association of chloroquine with alkylating and antimicrotubule agents in patient derived cell lines of glioblastoma
Authors: Kipper Franciele C. , Thomas Ajith , Lenz Guido 
Published: September 2020

Abstract
Autophagy is an important mechanism for cell survival after chemotherapy treatment. Many preclinical and clinical trials have tried to achieve tumor remission combining alkylating agents with autophagy inhibition. Chloroquine (CQ) has a long record as an autophagy inhibitor. In previous studies it was administered in vitro with mixed effects on central nervous system cell lines: while high doses of CQ were cytotoxic, low doses were neuroprotective. Preclinical studies showed that CQ could be used to treat glioblastoma, tumors derived from glial cells in the brain. In a phase I/II clinical trial combining CQ with the standard alkylating agent (temozolomide) plus radiotherapy treating patients with glioblastoma, a dose-limiting toxicity was observed at high doses. Although the authors reported that autophagy inhibition could not be achieved, they did not describe if this mechanism was involved in tumor resistance in that cohort of patients. In order to clarify if CQ can be used to block autophagy, we performed long term treatment combining low doses of CQ with chemotherapeutic agents. We used patient derived cell lines (PDCL) from glioblastoma tumors and treated them with therapeutic agents, using the reported plasma concentration of each drug. We measured acidic organelles with acridine orange incorporation 3, 5 and 7 days after addition of the treatment with flow cytometry. Additionally, 7 days after treatment surviving cells were counted. We did not observe significant increase in autophagy levels or decrease in cell number after temozolomide treatment. On the contrary, paclitaxel induced autophagy and decreased cell survival. Interestingly the combination of procarbazine, lomustine and vincristine (PCV), induced a broad range of results, ranging from high autophagy to increased cell death. We decided to combine PCV with CQ and perform long term analysis in order to evaluate the ability of cells undergoing or escaping apoptosis, senescence or mitotic catastrophe. After 5 days nuclear morphometric analysis demonstrated that out of 6 PDCL tested, only one presented an increase in senescence. The same PDCL also presented a decrease in total number of cells and increase in p62, although combining CQ with PCV was not better than PCV alone. Our results in vitro, using low concentrations of CQ corroborate the finding in clinical trials that chloroquine does not eliminate malignant cells in glioblastoma and better autophagy inhibitors need to be developed to achieve this goal.
Citation Format: Franciele C. Kipper, Ajith Thomas, Guido Lenz. In vitro association of chloroquine with alkylating and antimicrotubule agents in patient derived cell lines of glioblastoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1236.
Abstract 1241: Galectin-3 and the modulation of autophagy in the pancreatic cancer microenvironment
Authors: Felix Antonio , Consonni Silvio , Pitta Maira , Carvalho Hernandes , Pereira Michelly , Rêgo Moacyr 
Published: September 2020

Abstract
Galectin-3, a member of the β-galactoside binding proteins family was found up- regulated in pancreatic cancer and may be affected by microenvironment factors, such as hypoxia and/or nutritional deprivation. In this study, we aimed to analyze the effects of hypoxia and nutritional deprivation on the Galectin-3 protein levels and the possible influence of this galectin on the autophagy of pancreatic cancer cells. Nutritional deprivation was performed through partial or total reduction of fetal bovine serum (FBS) or through complete removal of serum, glucose and amino acids. Hypoxia was established with 1% oxygen tension. Proteins Galectin-3, Beclin- 1 and LC3 were accessed through Western blot and immunofluorescence. Induction of LC3 stable production was performed through transfection of pEGFP-LC3 and evaluated by confocal microcopy. Degradative vacuole quantification was done by transmission electron microscopy and knockdown of Galectin-3 was performed using siRNA transfection. According to the analyzes, the most effective conditions for the induction of autophagy were partial FBS deprivation for PANC-1 (p = 0.0035) and complete FBS/amino acid/glucose deprivation for Mia PaCa 2 cells (p = 0.0362). PANC-1 cells presented higher levels of Galectin-3 when they were submitted to 24 hours of FBS deprivation and simultaneously FBS deprivation and hypoxia. Hypoxia alone caused increases in LC3 levels for Mia PaCa-2 and for PANC-1 cells. Knockdown of Galectin-3 caused decreases of LC3 levels in almost all experimental conditions for both pancreatic cell lines with exception of concomitant nutritional deprivation and hypoxia for PANC-1. These results show that the Galectin-3 and LC-3 protein are modulated by hypoxia and nutritional deprivation. Cells incubated under hypoxia presented higher levels of LC3, what arguments in favor of the pro-autophagic aspects of hypoxia. Moreover, inhibition of Galectin-3 causes reduction of LC3, which implies Galectin-3 as an important regulator of the autophagic process in pancreatic cancer cells.
Key-words: Pancreatic Ductal Adenocarcinoma, LC3, Hypoxia, Nutritional deprivation.
Citation Format: Antonio Felix, Silvio Consonni, Maira Pitta, Hernandes Carvalho, Michelly Pereira, Moacyr Rêgo. Galectin-3 and the modulation of autophagy in the pancreatic cancer microenvironment [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1241.
Abstract 1242: RAB20 is a stress-induced regulator of mitochondrial homeostasis
Authors: Nayak Sunayana Govind , Shaw Samantha , Stets Colin , Dent Anthony , Strohecker Anne Marie 
Published: September 2020

Abstract
Mitochondrial homeostasis is tightly regulated via a combination of biogenesis and elimination via a form of selective autophagy called mitophagy. Given the importance of mitochondria for energy production, cellular redox status, and apoptotic signaling, the mitophagy pathway is of particular interest in cancer. While mitophagy has been reported to both assist and hinder tumorigenesis in different studies, the emerging consensus is that mitophagy supports tumor growth. Intriguingly, only a subset of the canonical autophagy machinery is required for mitophagy. Upstream regulators including ULK1, the phosphatidyl-inositol-3-phosphate (PI3P) effectors and components of the omegaosome DFCP1 and WIPI, and ATG9 are recruited to mitochondria independent of LC3. How these components are recruited to mitochondria and the mechanisms involved in engulfment/creation/scaling of the autophagosome around the mitochondrion are unclear. Here we report a novel role for the small GTPase RAB20 in mitochondrial homeostasis. Rab GTPases are master regulators of vesicle trafficking, templating membrane identity, coordinating vesicle docking, fusion, and cargo selection in concert with SNAREs and membrane tethers. Rab20 is normally expressed at low levels but can be induced by in vitro simulated metabolic stress (1% oxygen, glucose deprivation) or secondary to the stress of an actively growing tumor in vivo. Surprisingly, we discovered that silencing RAB20 in multiple Non-Small Cell Lung Cancer (NSCLC) cell lines impairs ischemia-induced mitophagy without impacting autophagic flux measured by LC3 lipidation. This defect is accompanied by an increase in mitochondrial mass. RAB20 silencing is associated with increased Reactive Oxygen Species both under nutrient replete and ischemic conditions. Further, Rab20 appears to influence mitochondrial network organization, manifest as elevated numbers of fragmented mitochondria in the Rab20 silenced cells compared to non-targeting vector isogenic vector control cells. Finally, mitochondrial respiration is impaired in RAB20 silenced cells. Taken together, this work indicates an important role for RAB20 in maintaining mitochondrial fitness. We are actively assessing the functional consequences of Rab20 ablation on lung tumorigenesis in an established mouse model of lung cancer driven by BrafV600E; Trp53−/−. These studies will be important in determining the role of RAB20 and its involvement in mitophagy on tumor progression in vivo.
Citation Format: Sunayana Govind Nayak, Samantha Shaw, Colin Stets, Anthony Dent, Anne Marie Strohecker. RAB20 is a stress-induced regulator of mitochondrial homeostasis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1242.
Abstract 1277: SPARCL1 exhibits different expression pattern between left- and right- sided colon cancer and it was down-regulated via DNA methylation
Authors: Wu Dehao , Cai Wen , Xu Junxi , Liu Xue , Bai Rui , Zheng Shu , Ge Weiting , Hu Hanguang 
Published: September 2020

Abstract
Background: We previously identified SPARC-like 1 (SPARCL1) as a suppressor for colon cancer metastasis. Recent studies confirmed its epigenetic modification in prostate cancer and osteosarcoma. Here we conducted in vivo and in vitro studies to investigate the mechanism of SPARCL1 epigenetic regulation and the relationship with clinicopathological features.
Method: Tissue array (271 left- [LCC] and 257 right-sided colon cancer [RCC]) and immunohistochemistry were performed to measure SPARCL1 expression. Methylation status was compared by bisulfite sequencing PCR between 17 LCC and 16 RCC. Epigenetic alteration and rescue experiment were performed in colon cancer cell lines (HCT-116, RKO and HT-29) using decitabine, panobinostat, or siRNA. Transwell assay was employed to compare cell mobility. Chi-square test, Mann-Whitney U test were used for comparing SPARCL1 expression or other clinical characteristics, and t-test for cell motility.
Result: RCC significantly lower expressed SPARCL1 protein than LCC (P =0.007). High methylated CpG site of SPARCL1 enriched in RCC not in LCC (56.25% vs. 29.41%). In vitro studies confirmed that decitabine could up regulate SPARCL1 transcription by 72-fold. Transwell assays further revealed that significant inhibition of decitabine in decreasing cells invasion and migration properties, which could be rescued by siRNA against SPARCL1. In addition, we didn't observe transcriptional alteration with panobinostat treatment.
Conclusion: DNA methylation not histone acetylation modulated SPARCL1 expression and suppress tumor metastasis, which may contribute to aberrant expression pattern and different clinical outcomes varying in left and right-colon cancer.
Citation Format: Dehao Wu, Wen Cai, Junxi Xu, Xue Liu, Rui Bai, Shu Zheng, Weiting Ge, Hanguang Hu. SPARCL1 exhibits different expression pattern between left- and right- sided colon cancer and it was down-regulated via DNA methylation [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1277.
Abstract 1285: Functional analysis of ZFHX4 as a novel therapeutic target in ovarian cancer
Authors: Oyama Yoshiko , Shigeta Shogo , Tsuji Keita , Tokunaga Hideki , Shimada Muneaki , Yaegashi Nobuo 
Published: September 2020

Abstract
[Introduction] Ovarian cancer is one of the most lethal gynecologic malignancies. More than half of the patients are diagnosed in advanced stages of disease where the prognosis is poor due to the inevitable acquired resistance to platinum agents. Although maintenance therapy with PARP inhibitors or bevacizumab has been proven to improve patient survival, platinum sensitivity is still the most important prognostic factor. Thus, novel therapeutic strategies effective for platinum-resistant cases or to overcome platinum-resistance are required.
Zinc Finger Homeobox 4 (ZFHX4) has been known as one of the major transcription regulators in nerve and muscle differentiation. Although not fully elucidated, recent researches including our genome-wide exploration indicate ZFHX4 is also involved in carcinogenesis and cancer progression. The objective of this study was to investigate the potential of ZFHX4 as a novel therapeutic target in ovarian cancer by analyzing clinical database and cell model experiments.
[Methods] Correlations between ZFHX4 mRNA expression and overall survival in 61 ovarian cancer cases treated at our institute and in the cases registered in TCGA database respectively were assessed by log-lank test. RNAi knockdown was introduced to several ovarian cancer cells to investigate the influence of ZFHX4 on cancer cell proliferation. Scratch assay was performed to assess the effect of RNAi knockdown on cell migration ability. Cells were also treated with cisplatin after 72 hours of siRNA transfection to assess the influence of ZHFX4 on platinum sensitivity.
[Results] Both in our clinical dataset and TCGA data, the overall survival was significantly poor in the group in which ZFHX4 is highly expressed. In cell model assay, ZFHX4 knockdown significantly suppressed ovarian cancer cell proliferation. Decreased motility was observed in the cells treated with siRNA targeting ZFHX4 by scratch assay. Furthermore, ZFHX4 knockdown increased cisplatin sensitivity in ovarian cancer cells.
[Conclusions] Altogether, our results suggest ZFHX4 functions to promote cancer cell proliferation, migration and platinum-resistance. Interruption of ZFHX4 function independently or in combination with platinum agents has a potential to bring benefit for the treatment of ovarian cancer.
Citation Format: Yoshiko Oyama, Shogo Shigeta, Keita Tsuji, Hideki Tokunaga, Muneaki Shimada, Nobuo Yaegashi. Functional analysis of ZFHX4 as a novel therapeutic target in ovarian cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1285.
Abstract 1308: CDK12 alterations define a distinct molecular subtype of prostate cancers with unique genomic and clinical characteristics
Authors: Nguyen Bastien , Mota Jose Mauricio , Nandakumar Subhiksha , Stopsack Konrad H. , Weg Emily , Rathkopf Dana , Morris Michael J. , Scher Howard , Kantoff Philip W. , Gopalan Anuradha , Zamarin Dmitriy , Solit David B. , Schultz Nikolaus , Abida Wassim 
Published: September 2020

Abstract
Background: CDK12 alterations are present in several tumor types but little is known regarding their oncogenic role and their clinical significance. Here we sought to describe the landscape of CDK12 alterations across solid cancers and the clinical features of CDK12-altered prostate cancer.
Methods: A total of 26,743 patients across 25 solid tumor types with available targeted sequencing data from MSK-IMPACT as part of their clinical care were included. Clinicopathological features and outcomes were assessed in prostate cancer. CDK12 alterations and association with genomic characteristics are described. For prostate cancer patients, overall survival from the date of metastasis and time to castration-resistance from the start of androgen deprivation therapy were assessed using univariable and multivariable Cox regression analysis.
Results: CDK12 alterations were identified in 404/26,743 (1.5%) patients overall, but were most frequent in prostate (100/1875, 5.3%) and ovarian cancer (43/1034, 4.2%) where they were associated with a high prevalence of truncating variants and biallelic inactivation. CDK12 alterations defined a distinct subtype of prostate cancer with more aggressive clinical features, a unique copy number alteration profile and involvement of distinct oncogenic pathway alterations, including cell cycle pathway genes. Independent of standard clinical factors and genomic instability, CDK12-altered prostate cancer patients were associated with shorter overall survival (median 64.4 vs 74.9 months, adjusted hazard ratio [aHR] 1.65, 95% CI 1.07-2.53, p = 0.03) and shorter time to the development of castration-resistant disease (median 10.8 months vs 13.1, aHR 1.43, 95%CI 1.07-1.8, p = 0.02).
Conclusions: CDK12 loss of function is a rare event across solid cancers but defines a distinct molecular subtype of prostate cancer that is associated with more aggressive clinical features and unique genomic alterations.
Citation Format: Bastien Nguyen, Jose Mauricio Mota, Subhiksha Nandakumar, Konrad H. Stopsack, Emily Weg, Dana Rathkopf, Michael J. Morris, Howard Scher, Philip W. Kantoff, Anuradha Gopalan, Dmitriy Zamarin, David B. Solit, Nikolaus Schultz, Wassim Abida. CDK12 alterations define a distinct molecular subtype of prostate cancers with unique genomic and clinical characteristics [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1308.