bluuebunny/crossref_metadata_2025 huggingface dataset:
Supplementary Figures 1-2 from Fisetin Enhances Chemotherapeutic Effect of Cabazitaxel against Human Prostate Cancer Cells
Authors: Mukhtar Eiman , Adhami Vaqar Mustafa , Siddiqui Imtiaz Ahmad , Verma Ajit Kumar , Mukhtar Hasan
Published: April 2023

Figure S1. Effect of fisetin and cabazitaxel, and their combination in-vitro.Figure S2. Effect of fisetin and cabazitaxel treatment of metastatic growth of PC-3M-luc-6 cell-derived tumors in mice.
Supplementary Table S1 from AZD6738, A Novel Oral Inhibitor of ATR, Induces Synthetic Lethality with ATM Deficiency in Gastric Cancer Cells
Authors: Min Ahrum , Im Seock-Ah , Jang Hyemin , Kim Seongyeong , Lee Miso , Kim Debora Keunyoung , Yang Yaewon , Kim Hee-Jun , Lee Kyung-Hun , Kim Jin Won , Kim Tae-Yong , Oh Do-Youn , Brown Jeff , Lau Alan , O'Connor Mark J. , Bang Yung-Jue
Published: April 2023

Anti-proliferative effects of AZD6738 on gastric cancer cell lines
Supplemental Figure 1 from Inhibition of Hsp90 Suppresses PI3K/AKT/mTOR Signaling and Has Antitumor Activity in Burkitt Lymphoma
Authors: Giulino-Roth Lisa , van Besien Herman J. , Dalton Tanner , Totonchy Jennifer E. , Rodina Anna , Taldone Tony , Bolaender Alexander , Erdjument-Bromage Hediye , Sadek Jouliana , Chadburn Amy , Barth Matthew J. , Dela Cruz Filemon S. , Rainey Allison , Kung Andrew L. , Chiosis Gabriela , Cesarman Ethel
Published: April 2023

Chemical Structure of PU-H71 and BEZ-235
Supplementary Figure S7 from AZD6738, A Novel Oral Inhibitor of ATR, Induces Synthetic Lethality with ATM Deficiency in Gastric Cancer Cells
Authors: Min Ahrum , Im Seock-Ah , Jang Hyemin , Kim Seongyeong , Lee Miso , Kim Debora Keunyoung , Yang Yaewon , Kim Hee-Jun , Lee Kyung-Hun , Kim Jin Won , Kim Tae-Yong , Oh Do-Youn , Brown Jeff , Lau Alan , O'Connor Mark J. , Bang Yung-Jue
Published: April 2023

ATM activity affected human gastric cancer cell line sensitivity to AZD6738
Supplementary Figure S6 from AZD6738, A Novel Oral Inhibitor of ATR, Induces Synthetic Lethality with ATM Deficiency in Gastric Cancer Cells
Authors: Min Ahrum , Im Seock-Ah , Jang Hyemin , Kim Seongyeong , Lee Miso , Kim Debora Keunyoung , Yang Yaewon , Kim Hee-Jun , Lee Kyung-Hun , Kim Jin Won , Kim Tae-Yong , Oh Do-Youn , Brown Jeff , Lau Alan , O'Connor Mark J. , Bang Yung-Jue
Published: April 2023

The basal expression of HDAC1 protein had a negative correlation with response to AZD6738 in gastric cancer cells
Supplementary Figures 1-4 from Targeting IκB Kinase β/NF-κB Signaling in Human Prostate Cancer by a Novel IκB Kinase β Inhibitor CmpdA
Authors: Zhang Yanting , Lapidus Rena G. , Liu Peiyan , Choi Eun Yong , Adediran Samusi , Hussain Arif , Wang Xinghuan , Liu Xuefeng , Dan Han C.
Published: April 2023

Supplementary Figure S1. IKKβ is activated by Akt, mTORC1 and IKKα in prostate cancer PC3 cells; Supplementary Figure S2. Expressions of EMT- and stemness-related factors in tissue microarrays representative of different stages of prostate cancer; Supplementary Figure S3. Inhibition of IKKβ/NF-κB by CmpdA in DU145 cells; Supplementary Figure S4. CmpdA inhibits DU145 cell migration.
Table S1 from Exposure-Response Analyses of Ramucirumab from Two Randomized, Phase III Trials of Second-line Treatment for Advanced Gastric or Gastroesophageal Junction Cancer
Authors: Tabernero Josep , Ohtsu Atsushi , Muro Kei , Van Cutsem Eric , Oh Sang Cheul , Bodoky György , Shimada Yasuhiro , Hironaka Shuichi , Ajani Jaffer A. , Tomasek Jiri , Safran Howard , Chandrawansa Kumari , Hsu Yanzhi , Heathman Michael , Khan Azhar , Ni Lan , Melemed Allen S. , Gao Ling , Ferry David , Fuchs Charles S.
Published: April 2023

Table S1 describes REGARD exposure-safety outcomes for Grade >=3 hypertension.
Supplementary Figure 3 from Identification of a Small Molecule That Overcomes HdmX-Mediated Suppression of p53
Authors: Karan Goutam , Wang Huaiyu , Chakrabarti Amit , Karan Sukanya , Liu Zhigang , Xia Zhiqiang , Gundluru Mahesh , Moreton Stephen , Saunthararajah Yogen , Jackson Mark W. , Agarwal Mukesh K. , Wald David N.
Published: April 2023

CTX1 specifically interacts with HdmX.
Supplementary Figure 1 from Identification of a Small Molecule That Overcomes HdmX-Mediated Suppression of p53
Authors: Karan Goutam , Wang Huaiyu , Chakrabarti Amit , Karan Sukanya , Liu Zhigang , Xia Zhiqiang , Gundluru Mahesh , Moreton Stephen , Saunthararajah Yogen , Jackson Mark W. , Agarwal Mukesh K. , Wald David N.
Published: April 2023

CTX1 rapidly induces p53 and p21 protein without causing evidence of DNA damage.
Supplementary Figure Legends from Osimertinib (AZD9291) Enhanced the Efficacy of Chemotherapeutic Agents in ABCB1- and ABCG2-Overexpressing Cells In Vitro, In Vivo, and Ex Vivo
Authors: Chen Zhen , Chen Yifan , Xu Meng , Chen Likun , Zhang Xu , To Kenneth Kin Wah , Zhao Hongyun , Wang Fang , Xia Zhongjun , Chen Xiaoqin , Fu Liwu
Published: April 2023

Figure Legend for Supplementary Figure 1
Supplemental Figure S4 from Optimization of a PEGylated Glucuronide-Monomethylauristatin E Linker for Antibody–Drug Conjugates
Authors: Burke Patrick J. , Hamilton Joseph Z. , Jeffrey Scott C. , Hunter Joshua H. , Doronina Svetlana O. , Okeley Nicole M. , Miyamoto Jamie B. , Anderson Martha E. , Stone Ivan J. , Ulrich Michelle L. , Simmons Jessica K. , McKinney Erica E. , Senter Peter D. , Lyon Robert P.
Published: April 2023

Bone marrow histopathology
Supplemental Figure S1 from Optimization of a PEGylated Glucuronide-Monomethylauristatin E Linker for Antibody–Drug Conjugates
Authors: Burke Patrick J. , Hamilton Joseph Z. , Jeffrey Scott C. , Hunter Joshua H. , Doronina Svetlana O. , Okeley Nicole M. , Miyamoto Jamie B. , Anderson Martha E. , Stone Ivan J. , Ulrich Michelle L. , Simmons Jessica K. , McKinney Erica E. , Senter Peter D. , Lyon Robert P.
Published: April 2023

SEC overlays of ADCs
Supplementary Figure S4 from PI3K Inhibitors Synergize with FGFR Inhibitors to Enhance Antitumor Responses in FGFR2mutant Endometrial Cancers
Authors: Packer Leisl M. , Geng Xinyan , Bonazzi Vanessa F. , Ju Robert J. , Mahon Clare E. , Cummings Margaret C. , Stephenson Sally-Anne , Pollock Pamela M.
Published: April 2023

Figure S4. FGFR and PI3K inhibitors were well tolerated in vivo, with no significant weight loss, and combined treatments resulted in disappearance of palpable tumor, as confirmed by autopsy.
Figure S5 from Targeting the MAPK Signaling Pathway in Cancer: Promising Preclinical Activity with the Novel Selective ERK1/2 Inhibitor BVD-523 (Ulixertinib)
Authors: Germann Ursula A. , Furey Brinley F. , Markland William , Hoover Russell R. , Aronov Alex M. , Roix Jeffrey J. , Hale Michael , Boucher Diane M. , Sorrell David A. , Martinez-Botella Gabriel , Fitzgibbon Matthew , Shapiro Paul , Wick Michael J. , Samadani Ramin , Meshaw Kathryn , Groover Anna , DeCrescenzo Gary , Namchuk Mark , Emery Caroline M. , Saha Saurabh , Welsch Dean J.
Published: April 2023

Combination interactions between BVD-523 and vemurafenib or dabrafenib were assessed in cell line (A) G361 and (B) A375 (n=3 for each). Growth inhibition and Loewe Excess is shown for 8 x 10 dose matrices. (C) BVD-523 in combination with dabrafenib markedly delays the onset of acquired resistance in A375 BRAFV600E melanoma cells.
Supplementary Table S2 from Cell Panel Profiling Reveals Conserved Therapeutic Clusters and Differentiates the Mechanism of Action of Different PI3K/mTOR, Aurora Kinase and EZH2 Inhibitors
Authors: Uitdehaag Joost C.M. , de Roos Jeroen A.D.M. , Prinsen Martine B.W. , Willemsen-Seegers Nicole , de Vetter Judith R.F. , Dylus Jelle , van Doornmalen Antoon M. , Kooijman Jeffrey , Sawa Masaaki , van Gerwen Suzanne J.C. , de Man Jos , Buijsman Rogier C. , Zaman Guido J.R.
Published: April 2023

Structures of compounds used in the study
Supplementary Figures S1-S11 and Table from Mechanisms of Resistance to NTRK Inhibitors and Therapeutic Strategies in NTRK1-Rearranged Cancers
Authors: Fuse Miho J. , Okada Koutaroh , Oh-hara Tomoko , Ogura Hayato , Fujita Naoya , Katayama Ryohei
Published: April 2023

Supplementary FigureS1ï¼š Sensitivity of TPM3â€�NTRK1 Ba/F3 clones to various NTRK1 inhibitors; Supplementary FigureS2ï¼š Sensitivity of TPM3â€�NTRK1 G595R mutant Ba/F3 cells to various NTRK1 inhibitors; Supplementary Figure S3ï¼š Sensitivity of TPM3â€�NTRK1 mutant induced Ba/F3 cells to NTRK1 inhibitors; Supplementary Figure S4ï¼š Sensitivity of TPM3â€�NTRK1 (WT) induced Ba/F3 cells and KM12 cells to crizotinib, ponatinib or Hsp90 inhibitor 17â€�AAG; Supplementary Figure S5. Cabozantinib, Ponatinib, or Entrectinib inhibited the tumor growth of KM12 cells in vivo.; Supplementary Figure S6ï¼š IGF1R activation mediated cabozantinib resistance in KM12 cells; Supplementary Figure S7ï¼š IGF1R activation mediated cabozantinib resistance in KM12 cells; Supplementary Figure S8ï¼š Cabozantinib resistance in KM12â€�CR20 cells are not sensitive to OSI906 monotherapy but sensitive to combination of OSI906 with NTRK inhibitors or NTRK/IGF1R dual inhibitor AZD3463; Supplementary Figure S9. Colony formation assay of KM12 cells; Supplementary Figure S10ï¼š Single cloneâ€�derived KM12 cells were sensitive to NTRKâ€�TKIs; Supplementary Figure S11. G595R resistant cells emerge from the single clone derived KM12 cells by selecting with Entrectinib; Supplementary Table S1ï¼š IC50s and relative IC50s of Ba/F3â€�TPM3â€�NTRK1 (WT and mutants) to each NTRK inhibitor; Supplementary Table S2ï¼š Drug screening of KM12 and cabozantinib resistant KM12â€�CR cells
Figure S6 from Mutual Influence of ROS, pH, and CLIC1 Membrane Protein in the Regulation of G1–S Phase Progression in Human Glioblastoma Stem Cells
Authors: Peretti Marta , Raciti Federica Maddalena , Carlini Valentina , Verduci Ivan , Sertic Sarah , Barozzi Sara , Garré Massimiliano , Pattarozzi Alessandra , Daga Antonio , Barbieri Federica , Costa Alex , Florio Tullio , Mazzanti Michele
Published: April 2023

Effect of IAA on apoptosis in GB CSCs.
Table S4 from Novel Fluoroindenoisoquinoline Non-Camptothecin Topoisomerase I Inhibitors
Authors: Marzi Laetitia , Agama Keli , Murai Junko , Difilippantonio Simone , James Amy , Peer Cody J. , Figg William D. , Beck Daniel , Elsayed Mohamed S.A. , Cushman Mark , Pommier Yves
Published: April 2023

Correlation of LMP135 cellular response with gene transcript levels, DNA methylation or genetic varients.
Figure S3 from IL6 Receptor Blockade Enhances Chemotherapy Efficacy in Pancreatic Ductal Adenocarcinoma
Authors: Long Kristen B. , Tooker Graham , Tooker Evan , Luque Santiago Lombo , Lee Jae W. , Pan Xiaoqing , Beatty Gregory L.
Published: April 2023

IL-6 activation of STAT3/SOCS3 in human monocytes
Table S1 from Novel Fluoroindenoisoquinoline Non-Camptothecin Topoisomerase I Inhibitors
Authors: Marzi Laetitia , Agama Keli , Murai Junko , Difilippantonio Simone , James Amy , Peer Cody J. , Figg William D. , Beck Daniel , Elsayed Mohamed S.A. , Cushman Mark , Pommier Yves
Published: April 2023

Correlation of fluoroindenoisoquinolines with TOP1 inhibitors and example of negative correlation with Paclitaxel and Erlotinib
Figure S1 from IL6 Receptor Blockade Enhances Chemotherapy Efficacy in Pancreatic Ductal Adenocarcinoma
Authors: Long Kristen B. , Tooker Graham , Tooker Evan , Luque Santiago Lombo , Lee Jae W. , Pan Xiaoqing , Beatty Gregory L.
Published: April 2023

Gating strategy for human PBMCs
Table S3 from A Potent Blood–Brain Barrier-Permeable Mutant IDH1 Inhibitor Suppresses the Growth of Glioblastoma with IDH1 Mutation in a Patient-Derived Orthotopic Xenograft Model
Authors: Machida Yukino , Nakagawa Makoto , Matsunaga Hironori , Yamaguchi Masayuki , Ogawara Yoko , Shima Yutaka , Yamagata Kazutsune , Katsumoto Takuo , Hattori Ayuna , Itoh Masato , Seki Takahiko , Nishiya Yumi , Nakamura Koichi , Suzuki Kanae , Imaoka Tomoki , Baba Daichi , Suzuki Makoto , Sampetrean Oltea , Saya Hideyuki , Ichimura Koichi , Kitabayashi Issay
Published: April 2023

Table S3 shows mean concentration of DS-1001a in plasma, brain, and cerebrum in mice.
Supplementary Table S2 from A Pilot Study of Galunisertib plus Stereotactic Body Radiotherapy in Patients with Advanced Hepatocellular Carcinoma
Authors: Reiss Kim A. , Wattenberg Max M. , Damjanov Nevena , Prechtel Dunphy Elizabeth , Jacobs-Small Mona , Lubas M. Judy , Robinson James , Dicicco Lisa , Garcia-Marcano Luis , Giannone Michael A. , Karasic Thomas B. , Furth Emma E. , Carpenter Erica L. , Wojcieszynski Andrzej P. , Vonderheide Robert H. , Beatty Gregory L. , Ben-Josef Edgar
Published: April 2023

Radiation doses to organs-at-risk
Supplementary Table 1 from Single-Dose Anti–PD-L1/IL-15 Fusion Protein KD033 Generates Synergistic Antitumor Immunity with Robust Tumor-Immune Gene Signatures and Memory Responses
Authors: Martomo Stella A. , Lu Dan , Polonskaya Zhanna , Luna Xenia , Zhang Zhikai , Feldstein Sam , Lumban-Tobing Radovan , Almstead Danielle K. , Miyara Faical , Patel Jeegar
Published: April 2023

Analysis of KD033-Mediated Activation of Peripheral Immune Cell Populations in Cynomolgus Monkeys
Supplemental figure 5 from Role of Dimerized C16orf74 in Aggressive Pancreatic Cancer: A Novel Therapeutic Target
Authors: Kushibiki Toshihiro , Nakamura Toru , Tsuda Masumi , Tsuchikawa Takahiro , Hontani Koji , Inoko Kazuho , Takahashi Mizuna , Asano Toshimichi , Okamura Keisuke , Murakami Soichi , Kurashima Yo , Ebihara Yuma , Noji Takehiro , Nakanishi Yoshitsugu , Tanaka Kimitaka , Maishi Nako , Sasaki Katsunori , Park Woong-Ryeon , Shichinohe Toshiaki , Hida Kyoko , Tanaka Shinya , Hirano Satoshi
Published: April 2023

Supplemental Figure 5 shows (A) treatment schedule of subcutaneous model, (B) therapeutic result of PK-9 subcutaneous tumor model mice (n= 5). 3 groups (PBS: non-treatment group, 11R-7_14 AAA: negative control peptide group, 11R-DB: treatment group). In the 11R-DB group, tumor growth was suppressed significantly (11R-DB vs 11R-7â,‹14AAA and PBS: *p<0.05, 11R-7â,‹14AAA vs PBS: n.s). Data were presented as mean {plus minus} SEM (each group n = 5), (C) tumor weights at 3 weeks after start of treatment in each group, (D) the body weight of mice before treatment after treatment in each group. Data are presented as mean {plus minus} SEM (N=6), and (E) sections of major organs after treatment were stained with hematoxylin and eosin. No obvious abnormal findings were observed in any organ.
Supplementary Figure S2 from Synthetic Lethality with Trifluridine/Tipiracil and Checkpoint Kinase 1 Inhibitor for Esophageal Squamous Cell Carcinoma
Authors: Ohashi Shinya , Kikuchi Osamu , Nakai Yukie , Ida Tomomi , Saito Tomoki , Kondo Yuki , Yamamoto Yoshihiro , Mitani Yosuke , Nguyen Vu Trang H. , Fukuyama Keita , Tsukihara Hiroshi , Suzuki Norihiko , Muto Manabu
Published: April 2023

TP53 and other DNA damage response-related gene mutations in human esophageal squamous cell carcinomas.
Supplementary Figures S1-S5 from A Cell-Based MAPK Reporter Assay Reveals Synergistic MAPK Pathway Activity Suppression by MAPK Inhibitor Combination in BRAF-Driven Pediatric Low-Grade Glioma Cells
Authors: Usta Diren , Sigaud Romain , Buhl Juliane L. , Selt Florian , Marquardt Viktoria , Pauck David , Jansen Jennifer , Pusch Stefan , Ecker Jonas , Hielscher Thomas , Vollmer Johanna , Sommerkamp Alexander C. , Rubner Tobias , Hargrave Darren , van Tilburg Cornelis M. , Pfister Stefan M. , Jones David T.W. , Remke Marc , Brummer Tilman , Witt Olaf , Milde Till
Published: April 2023

Suppl. Figure S1 shows "Initial MAPKi screen using metabolic activity as readout". Suppl. Figure S2 shows "Western blot validation of MAPK pathway alterations in HEK293T cells". Suppl. Figure S3 shows "Dose-response curves of MAPKi combination treatment in DKFZ-BT66 pDIPZ-CMV cells". Suppl. Figure S4 shows "Dose response curves of MAPKi combination treatment in BT 40 pDIPZ CMV cells". Suppl. Figure S5 shows "Isobolograms of MAPKi combination treatment in DKFZ-BT66 pDIPZ-CMV and BT-40 pDIPZ-CMV cells"
Supplementary Table from Exploiting Ligand-binding Domain Dimerization for Development of Novel Androgen Receptor Inhibitors
Authors: Helsen Christine , Nguyen Tien T. , Lee Xiao Yin , Eerlings Roy , Louros Nikolaos , Schymkowitz Joost , Rousseau Frederic , Claessens Frank , Voet Arnout
Published: April 2023

Supplementary Table from Exploiting Ligand-binding Domain Dimerization for Development of Novel Androgen Receptor Inhibitors
Data from Targeting Peroxisome Proliferator-Activated Receptor γ to Increase Estrogen-Induced Apoptosis in Estrogen-Deprived Breast Cancer Cells
Authors: Fan Ping , Abderrahman Balkees , Chai Tina S. , Yerrum Smitha , Jordan V. Craig
Published: April 2023

Abstract
Peroxisome proliferator-activated receptor γ (PPARγ) is an important transcription factor that modulates lipid metabolism and inflammation. However, it remains unclear whether PPARγ is involved in modulation of estrogen (E2)-induced inflammation, thus affecting apoptosis of E2-deprived breast cancer cells, MCF-7:5C and MCF-7:2A. Here, we demonstrated that E2 treatment suppressed the function of PPARγ in both cell lines, although the suppressive effect in MCF-7:2A cells was delayed owing to high PPARγ expression. Activation of PPARγ by a specific agonist, pioglitazone, selectively blocked the induction of TNFα expression by E2, but did not affect other adipose inflammatory genes, such as fatty acid desaturase 1 and IL6. This suppression of TNFα expression by pioglitazone was mainly mediated by transrepression of nuclear factor-κB (NF-κB) DNA-binding activity. A novel finding was that NF-κB functions as an oxidative stress inducer in MCF-7:5C cells but an antioxidant in MCF-7:2A cells. Therefore, the NF-κB inhibitor JSH-23 displayed effects equivalent to those of pioglitazone, with complete inhibition of apoptosis in MCF-7:5C cells, but it increased E2-induced apoptosis in MCF-7:2A cells. Depletion of PPARγ by siRNA or the PPARγ antagonist T0070907 accelerated E2-induced apoptosis, with activation of NF-κB–dependent TNFα and oxidative stress. For the first time, we demonstrated that PPARγ is a growth signal and has potential to modulate NF-κB activity and oxidative stress in E2-deprived breast cancer cell lines. All of these findings suggest that anti-PPARγ therapy is a novel strategy to improve the therapeutic effects of E2-induced apoptosis in E2-deprived breast cancer.
Data from Atovaquone: An Antiprotozoal Drug Suppresses Primary and Resistant Breast Tumor Growth by Inhibiting HER2/β-Catenin Signaling
Authors: Gupta Nehal , Srivastava Sanjay K.
Published: April 2023

Abstract
Breast cancer is the second leading cause of cancer-related mortality in women. In the current study, we evaluated the anticancer effects of an antiprotozoal drug, atovaquone, against several breast cancer cell lines. Our results showed that atovaquone treatment induced apoptosis and inhibited the growth of all the breast cancer cell lines tested, including several patient-derived cells. In addition, atovaquone treatment significantly reduced the expression of HER2, β-catenin, and its downstream molecules such as pGSK-3β, TCF-4, cyclin D1, and c-Myc in vitro. Efficacy of atovaquone was further evaluated in an in vivo tumor model by orthotropic implantation of two highly aggressive 4T1 and CI66 breast cancer cells in the mammary fat pad of female mice. Our results demonstrated that oral administration of atovaquone suppressed the growth of CI66 and 4T1 tumors by 70% and 60%, respectively. Paclitaxel is the first-line chemotherapeutic agent for metastatic breast cancer. We demonstrate that atovaquone administration suppressed the growth of 4T1 paclitaxel-resistant tumors by 40%. Tumors from atovaquone-treated mice exhibited reduced HER2, β-catenin, and c-Myc levels alongside an increase in apoptosis in all the three tumor models when analyzed by Western blotting, IHC, and TUNEL assay. Taken together, our results indicate that atovaquone effectively reduces the growth of primary and paclitaxel-resistant breast tumors. Atovaquone is already in the clinics with high safety and tolerability profile. Therefore, the findings from our studies will potentially prompt further clinical investigation into repurposing atovaquone for the treatment of patients with advanced breast cancer.
Data from APTO-253 Stabilizes G-quadruplex DNA, Inhibits MYC Expression, and Induces DNA Damage in Acute Myeloid Leukemia Cells
Authors: Local Andrea , Zhang Hongying , Benbatoul Khalid D. , Folger Peter , Sheng Xia , Tsai Cheng-Yu , Howell Stephen B. , Rice William G.
Published: April 2023

Abstract
APTO-253 is a phase I clinical stage small molecule that selectively induces CDKN1A (p21), promotes G0–G1 cell-cycle arrest, and triggers apoptosis in acute myeloid leukemia (AML) cells without producing myelosuppression in various animal species and humans. Differential gene expression analysis identified a pharmacodynamic effect on MYC expression, as well as induction of DNA repair and stress response pathways. APTO-253 was found to elicit a concentration- and time-dependent reduction in MYC mRNA expression and protein levels. Gene ontogeny and structural informatic analyses suggested a mechanism involving G-quadruplex (G4) stabilization. Intracellular pharmacokinetic studies in AML cells revealed that APTO-253 is converted intracellularly from a monomer to a ferrous complex [Fe(253)3]. FRET assays demonstrated that both monomeric APTO-253 and Fe(253)3 stabilize G4 structures from telomeres, MYC, and KIT promoters but do not bind to non-G4 double-stranded DNA. Although APTO-253 exerts a host of mechanistic sequelae, the effect of APTO-253 on MYC expression and its downstream target genes, on cell-cycle arrest, DNA damage, and stress responses can be explained by the action of Fe(253)3 and APTO-253 on G-quadruplex DNA motifs. Mol Cancer Ther; 17(6); 1177–86. ©2018 AACR.
Data from Preclinical Evaluation of Nintedanib, a Triple Angiokinase Inhibitor, in Soft-tissue Sarcoma: Potential Therapeutic Implication for Synovial Sarcoma
Authors: Patwardhan Parag P. , Musi Elgilda , Schwartz Gary K.
Published: April 2023

Abstract
Sarcomas are rare cancers that make up about 1% of all cancers in adults; however, they occur more commonly among children and young adolescents. Sarcomas are genetically complex and are often difficult to treat given the lack of clinical efficacy of any of the currently available therapies. Receptor tyrosine kinases (RTK) such as c-Kit, c-Met, PDGFR, IGF-1R, as well as FGFR have all been reported to be involved in driving tumor development and progression in adult and pediatric soft-tissue sarcoma. These driver kinases often act as critical determinants of tumor cell proliferation and targeting these signal transduction pathways remains an attractive therapeutic approach. Nintedanib, a potent triple angiokinase inhibitor, targets PDGFR, VEGFR, and FGFR pathways critical for tumor angiogenesis and vasculature. In this study, we evaluated the preclinical efficacy of nintedanib in soft-tissue sarcoma cell lines. Nintedanib treatment resulted in significant antiproliferative effect in vitro in cell lines with high expression of RTK drug targets. Furthermore, treatment with nintedanib showed significant downregulation of downstream phosphorylated AKT and ERK1/2. Finally, treatment with nintedanib resulted in significant tumor growth suppression in mouse xenograft model of synovial sarcoma. Notably, both the in vitro and in vivo efficacy of nintedanib was superior to that of imatinib, another multikinase inhibitor, previously tested with minimal success in clinical trials in sarcoma. Overall, the data from this study provide a strong rationale to warrant further clinical exploration of this drug in patients with synovial sarcoma. Mol Cancer Ther; 17(11); 2329–40. ©2018 AACR.
Data from TAS-114, a First-in-Class Dual dUTPase/DPD Inhibitor, Demonstrates Potential to Improve Therapeutic Efficacy of Fluoropyrimidine-Based Chemotherapy
Authors: Yano Wakako , Yokogawa Tatsushi , Wakasa Takeshi , Yamamura Keisuke , Fujioka Akio , Yoshisue Kunihiro , Matsushima Eiji , Miyahara Seiji , Miyakoshi Hitoshi , Taguchi Junko , Chong Khoon Tee , Takao Yayoi , Fukuoka Masayoshi , Matsuo Kenichi
Published: April 2023

Abstract
5-Fluorouracil (5-FU) is an antimetabolite and exerts antitumor activity via intracellularly and physiologically complicated metabolic pathways. In this study, we designed a novel small molecule inhibitor, TAS-114, which targets the intercellular metabolism of 5-FU to enhance antitumor activity and modulates catabolic pathway to improve the systemic availability of 5-FU. TAS-114 strongly and competitively inhibited deoxyuridine 5′-triphosphate nucleotidohydrolase (dUTPase), a gatekeeper protein preventing aberrant base incorporation into DNA, and enhanced the cytotoxicity of fluoropyrimidines in cancer cells; however, it had little intrinsic activity. In addition, TAS-114 had moderate and reversible inhibitory activity on dihydropyrimidine dehydrogenase (DPD), a catabolizing enzyme of 5-FU. Thus, TAS-114 increased the bioavailability of 5-FU when coadministered with capecitabine in mice, and it significantly improved the therapeutic efficacy of capecitabine by reducing the required dose of the prodrug by dual enzyme inhibition. Enhancement of antitumor efficacy caused by the addition of TAS-114 was retained in the presence of a potent DPD inhibitor containing oral fluoropyrimidine (S-1), indicating that dUTPase inhibition plays a major role in enhancing the antitumor efficacy of fluoropyrimidine-based therapy. In conclusion, TAS-114, a dual dUTPase/DPD inhibitor, demonstrated the potential to improve the therapeutic efficacy of fluoropyrimidine. Dual inhibition of dUTPase and DPD is a novel strategy for the advancement of oral fluoropyrimidine-based chemotherapy for cancer treatment. Mol Cancer Ther; 17(8); 1683–93. ©2018 AACR.
Data from Induced Telomere Damage to Treat Telomerase Expressing Therapy-Resistant Pediatric Brain Tumors
Authors: Sengupta Satarupa , Sobo Matthew , Lee Kyungwoo , Senthil Kumar Shiva , White Angela R. , Mender Ilgen , Fuller Christine , Chow Lionel M.L. , Fouladi Maryam , Shay Jerry W. , Drissi Rachid
Published: April 2023

Abstract
Brain tumors remain the leading cause of cancer-related deaths in children and often are associated with long-term sequelae among survivors of current therapies. Hence, there is an urgent need to identify actionable targets and to develop more effective therapies. Telomerase and telomeres play important roles in cancer, representing attractive therapeutic targets to treat children with poor-prognosis brain tumors such as diffuse intrinsic pontine glioma (DIPG), high-grade glioma (HGG), and high-risk medulloblastoma. We have previously shown that DIPG, HGG, and medulloblastoma frequently express telomerase activity. Here, we show that the telomerase-dependent incorporation of 6-thio-2′deoxyguanosine (6-thio-dG), a telomerase substrate precursor analogue, into telomeres leads to telomere dysfunction–induced foci (TIF) along with extensive genomic DNA damage, cell growth inhibition, and cell death of primary stem-like cells derived from patients with DIPG, HGG, and medulloblastoma. Importantly, the effect of 6-thio-dG is persistent even after drug withdrawal. Treatment with 6-thio-dG elicits a sequential activation of ATR and ATM pathways and induces G2–M arrest. In vivo treatment of mice bearing medulloblastoma xenografts with 6-thio-dG delays tumor growth and increases in-tumor TIFs and apoptosis. Furthermore, 6-thio-dG crosses the blood–brain barrier and specifically targets tumor cells in an orthotopic mouse model of DIPG. Together, our findings suggest that 6-thio-dG is a promising novel approach to treat therapy-resistant telomerase-positive pediatric brain tumors. Mol Cancer Ther; 17(7); 1504–14. ©2018 AACR.
Data from ST8SIA1 Regulates Tumor Growth and Metastasis in TNBC by Activating the FAK–AKT–mTOR Signaling Pathway
Authors: Nguyen Khoa , Yan Yuanqing , Yuan Bin , Dasgupta Abhishek , Sun Jeffrey , Mu Hong , Do Kim-Anh , Ueno Naoto T. , Andreeff Michael , Battula V. Lokesh
Published: April 2023

Abstract
Breast cancer stem-like cells (BCSC) are implicated in cancer recurrence and metastasis of triple-negative breast cancer (TNBC). We have recently discovered that ganglioside GD2 expression defines BCSCs and that ST8SIA1 regulates GD2 expression and BCSC function. In this report, we show that ST8SIA1 is highly expressed in primary TNBC; its expression is positively correlated with the expression of several BCSC-associated genes such as BCL11A, FOXC1, CXCR4, PDGFRβ, SOX2, and mutations in p53. CRISPR knockout of ST8SIA1 completely inhibited BCSC functions, including in vitro tumorigenesis and mammosphere formation. Mechanistic studies discovered activation of the FAK–AKT–mTOR signaling pathway in GD2+ BCSCs, and its tight regulation by ST8SIA1. Finally, knockout of ST8SIA1 completely blocked in vivo tumor growth and metastasis by TNBC cells. In summary, these data demonstrate the mechanism by which ST8SIA1 regulates tumor growth and metastasis in TNBC and identifies it as a novel therapeutic target.
Data from Molecularly Targeted Cancer Combination Therapy with Near-Infrared Photoimmunotherapy and Near-Infrared Photorelease with Duocarmycin–Antibody Conjugate
Authors: Nagaya Tadanobu , Gorka Alexander P. , Nani Roger R. , Okuyama Shuhei , Ogata Fusa , Maruoka Yasuhiro , Choyke Peter L. , Schnermann Martin J. , Kobayashi Hisataka
Published: April 2023

Abstract
Near-infrared photoimmunotherapy (NIR-PIT) is a highly selective tumor treatment that uses an antibody–photoabsorber conjugate (APC). However, the effect of NIR-PIT can be enhanced when combined with other therapies. NIR photocaging groups, based on the heptamethine cyanine scaffold, have been developed to release bioactive molecules near targets after exposure to light. Here, we investigated the combination of NIR-PIT using panitumumab–IR700 (pan-IR700) and the NIR-releasing compound, CyEt–panitumumab–duocarmycin (CyEt-Pan-Duo). Both pan-IR700 and CyEt-Pan-Duo showed specific binding to the EGFR-expressing MDAMB468 cell line in vitro. In in vivo studies, additional injection of CyEt-Pan-Duo immediately after NIR light exposure resulted in high tumor accumulation and high tumor–background ratio. To evaluate the effects of combination therapy in vivo, tumor-bearing mice were separated into 4 groups: (i) control, (ii NIR-PIT, (iii) NIR-release, (iv) combination of NIR-PIT and NIR-release. Tumor growth was significantly inhibited in all treatment groups compared with the control group (P < 0.05), and significantly prolonged survival was achieved (P < 0.05 vs. control). The greatest therapeutic effect was shown with NIR-PIT and NIR-release combination therapy. In conclusion, combination therapy of NIR-PIT and NIR-release enhanced the therapeutic effects compared with either NIR-PIT or NIR-release therapy alone. Mol Cancer Ther; 17(3); 661–70. ©2017 AACR.
Data from Lack of Constitutively Active DNA Repair Sensitizes Glioblastomas to Akt Inhibition and Induces Synthetic Lethality with Radiation Treatment in a p53-Dependent Manner
Authors: Palanichamy Kamalakannan , Patel Disha , Jacob John R. , Litzenberg Kevin T. , Gordon Nicolaus , Acus Kirstin , Noda Shin-ei , Chakravarti Arnab
Published: April 2023

Abstract
Treatment refractory glioblastoma (GBM) remains a major clinical problem globally, and targeted therapies in GBM have not been promising to date. The Cancer Genome Atlas integrative analysis of GBM reported the striking finding of genetic alterations in the p53 and PI3K pathways in more than 80% of GBMs. Given the role of these pathways in making cell-fate decisions and responding to genotoxic stress, we investigated the reliance of these two pathways in mediating radiation resistance. We selected a panel of GBM cell lines and glioma stem cells (GSC) with wild-type TP53 (p53-wt) and mutant TP53, mutations known to interfere with p53 functionality (p53-mt). Cell lines were treated with a brain permeable inhibitor of P-Akt (ser473), phosphatidylinositol ether lipid analogue (PIA), with and without radiation treatment. Sensitivity to treatment was measured using Annexin-V/PI flow cytometry and Western blot analysis for the markers of apoptotic signaling, alkaline COMET assay. All results were verified in p53 isogenic cell lines. p53-mt cell lines were selectively radiosensitized by PIA. This radiosensitization effect corresponded with an increase in DNA damage and a decrease in DNA-PKcs levels. TP53 silencing in p53-wt cells showed a similar response as the p53-mt cells. In addition, the radiosensitization effects of Akt inhibition were not observed in normal human astrocytes, suggesting that this treatment strategy could have limited off-target effects. We demonstrate that the inhibition of the PI3K/Akt pathway by PIA radiosensitizes p53-mt cells by antagonizing DNA repair. In principle, this strategy could provide a large therapeutic window for the treatment of TP53-mutant tumors. Mol Cancer Ther; 17(2); 336–46. ©2017 AACR.

See all articles in this MCT Focus section, “Developmental Therapeutics in Radiation Oncology.”
Data from U3-1402, a Novel HER3-Targeting Antibody–Drug Conjugate, for the Treatment of Colorectal Cancer
Authors: Koganemaru Shigehiro , Kuboki Yasutoshi , Koga Yoshikatsu , Kojima Takashi , Yamauchi Mayumi , Maeda Naoyuki , Kagari Takashi , Hirotani Kenji , Yasunaga Masahiro , Matsumura Yasuhiro , Doi Toshihiko
Published: April 2023

Abstract
HER3 is overexpressed in several cancers, including colorectal cancer. Although therapies with anti-HER3 antibodies have been investigated, significant clinical benefits have not been reported. U3-1402 is a novel HER3-antibody–drug conjugate (ADC) composed of the HER3 antibody patritumab and a novel topoisomerase I inhibitor, DX-8951 derivative (DXd). The sensitivity of DXd was evaluated by a growth inhibition assay. The antitumor activity of U3-1402 was evaluated in a murine xenograft model in which its effects on cells, with a range of HER3 expression levels, were compared with those of patritumab alone, irinotecan, control-ADC, and saline. In the growth inhibition assay, all colorectal cancer cell lines were sensitive to DXd. In the tumor xenograft model, significant tumor regression with U3-1402 was observed both in the DiFi cell line (high HER3 expression; KRAS wild type) and in SW620 (high HER3 expression; KRAS mutation), but no treatment effect was observed in Colo320DM (low HER3 expression). Notably, SW620 tumor growth was significantly suppressed with U3-1402 compared with the saline-treated group (P < 0.001) and showed greater activity compared with the irinotecan group. By contrast, patritumab alone, control-ADC, and saline did not significantly differ in tumor growth inhibition. The antitumor activity of U3-1402 was dependent on HER3 expression level, but not on KRAS mutation status. These results support further investigation of development strategies for U3-1402 in patients with HER3-expressing colorectal cancer.
Data from Targeted Sequencing of Circulating Tumor DNA to Monitor Genetic Variants and Therapeutic Response in Metastatic Colorectal Cancer
Authors: Hsu Hung-Chih , Lapke Nina , Wang Chuang-Wei , Lin Pei-Yi , You Jeng Fu , Yeh Chien Yuh , Tsai Wen-Sy , Hung Hsin Yuan , Chiang Sum-Fu , Chen Hua-Chien , Chen Shu-Jen , Hsu An , Yang Tsai Sheng
Published: April 2023

Abstract
Substantial improvements have been made in the management of metastatic colorectal cancer (mCRC) in the last two decades, but disease monitoring remains underdeveloped. Circulating tumor DNA (ctDNA) is a promising prognostic and predictive biomarker; however, ctDNA as a marker for mCRC patients is not well established, and there is still no consensus about how to utilize it most cost-effectively. In this study, we aim to investigate plasma ctDNA levels as a biomarker for therapeutic response of mCRC patients. We performed next-generation sequencing (NGS) by using a 12-gene panel to identify genetic variants in 136 tumor tissue and ctDNA samples from 32 mCRC patients. Genetic variants were detected in approximately 70% of samples, and there was a high concordance (85%) between tumor tissue and plasma ctDNA. We observed ctDNA changes in 18 follow-up patients, including the emergence of new variants. Changes in ctDNA levels significantly correlated with tumor shrinkage (P = 0.041), and patients with a ctDNA decrease >80% after treatment had a longer progression-free survival compared with patients with a ctDNA decrease of <80% (HR, 0.22; P = 0.015). The objective response rate among patients with a ctDNA decrease of >80% was better than those with a ctDNA decrease <80% (OR, 0.026; P = 0.007). In conclusion, this study demonstrates that monitoring of genetic ctDNA variants can serve as a valuable biomarker for therapeutic efficacy in mCRC patients, and that using a moderate-sized 12-gene NGS panel may be suitable for such clinical monitoring. Mol Cancer Ther; 17(10); 2238–47. ©2018 AACR.
Abstract 1019: Altona regression model: a new prognostic model for breast cancer patients after neoadjuvant treatment
Authors: Wegscheider Anne-Sophie , Lotfy-Eckmann Katharina , Ulm Bernhard , Lindner Christoph , Friedrichs Kay , Niendorf Axel
Published: April 2023

The purpose of the study was to create a new prognostic model for breast cancer (BC) patients that had been treated with a preoperative neoadjuvant chemotherapy, considering different parameters of regressive changes in the residual tumor (RT) respectively the tumor bed (TB).

HE-stained whole-slide images of 518 patients, treated between 2001-2019 in Hamburg, Germany following current therapy standards, were analyzed regarding different variables of regressive changes in the pretherapeutic diagnosed BC. First, size of RT and TB was measured, lymph node metastasis and residual intraductal carcinoma in situ were noted. Additional parameters that were examined were cell density and cell shape of RT, heterogeneity of residual tumor cells spreading within the TB and size of the biggest cell clusters as well as changes of the stroma and inflammation within the TB.

Data were used pseudo-anonymized after consent was given by the patients and a positive vote of the ethics committee.

In the univariate observation of above-mentioned variables it was shown that heterogeneity, cell density and cell shape of residual tumor cells, stroma changes and the presence of lymph node metastases as well as largest diameter and largest cluster of RT have an impact on progression free survival. Using decision tree analysis, the patient cohort could be divided in three risk groups with significant different outcome regarding progression free survival with low, intermediate and high risk for an event (local recurrence of disease, metastasis, death). Our multivariate "Altona regression model", that was constructed using Cox regression, showed significantly better prognostic value concerning progression free survival for BC patients after neoadjuvant therapy and following surgery, compared to two well-known regression gradings by Sinn et al. and MD Anderson (RCB).

Comparison of regression models Altona Sinn et al. RCB Altona vs. Sinn Altona vs. RCB Sinn vs. RCB iAUC 0.607 0.350 0.380 < 0.001 < 0.001 < 0.001 Concordance 0.788 0.378 0.478 < 0.001 < 0.001 < 0.001

Citation Format: Anne-Sophie Wegscheider, Katharina Lotfy-Eckmann, Bernhard Ulm, Christoph Lindner, Kay Friedrichs, Axel Niendorf. Altona regression model: a new prognostic model for breast cancer patients after neoadjuvant treatment [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 1019.
Abstract 1064: Cancer-specific molecular subtypes of pancreatic cancer reveal clinically relevant molecular dependency
Authors: Lee Sung Hwan , Park Jiyeon , Lee Sunyoung , Lee Ju-Seog
Published: April 2023

Introduction: Pancreatic cancer is lethal, showing dismal prognosis and therapeutic resistance. Previous molecular subtypes from genome or transcriptome did not show clinical relevance regarding precision strategy for optimal therapeutic options followed by precise patient classification. This study aims to uncover consensus molecular subtypes from cancer-specific multi-omics data showing clinically relevant therapeutic opportunities.

Methods: We performed comprehensive analyses using the dataset from the cancer dependency map (DepMap) project, including cancer-specific molecular characterization with multi-omics data, genome-wide loss-of-function screening using the CRISPR-Cas9 system, and cancer drug sensitivity. The subtype-specific molecular signatures were validated in independent translational cohorts (TCGA-PAAD; n=150, ICGC-PACA-AU; n=461, ICGC-PACA-CA; n=317).

Results: Integrative profiling of multi-omics molecular layers (Mutational signature, Copy number alteration, Transcriptome, MicroRNA, Chromatic profile, Proteome, and Metabolome) from pancreatic cancer cell lines (n=59) from the Cancer Cell Line Encyclopedia (CCLE) revealed a total of three cancer-specific molecular subtypes showing distinct tumor biology through all omics layer as well as clinical relevance with unique molecular dependency. Major molecular features of each subtype were reproducible in the validation cohorts. Subtype-specific molecular biomarkers, including mutational signatures and metabolites, were identified. Finally, the target drug with subtype-specific genetic dependency was analyzed to provide a precision strategy according to distinct subtypes’ molecular characterization.

Conclusions: Integrative profiling from multi-omics molecular layers revealed precision strategies based on cancer-specific molecular subtypes of pancreatic cancer in terms of tumor classification and discriminative therapeutic opportunities. Prospective translational studies companion with clinical trials based on cancer-specific molecular subtypes is mandatory to establish the precision strategy for managing pancreatic cancer.

Citation Format: Sung Hwan Lee, Jiyeon Park, Sunyoung Lee, Ju-Seog Lee. Cancer-specific molecular subtypes of pancreatic cancer reveal clinically relevant molecular dependency [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 1064.
Abstract 1137: Identification of a high selective SMARCA2 degrader which effectively suppresses the SMARCA4-deficient tumors in vitro and in vivo
Authors: Zhou Feng , Yu Zhiyong , Chen Ruonan , Tang Feng , Gu Peng , Yang Wenqing , Xue Liting , Chen Ping , Tang Renhong
Published: April 2023

The SWI/SNF chromatin-remodeling complex plays essential roles in a variety of cellular processes including differentiation, proliferation and DNA repair. Mammalian SWI/SNF complexes always contain one of two mutually exclusive and structurally highly related ATPases: SMARCA2/BRM or SMARCA4/BRG1, as its catalytic subunit, which hydrolyze ATP to drive nucleosome movement. It is reported that absence of SMARCA4 are present in several cancers and these SMARCA4 deficient cells highly depend on its paralog SMARCA2 for survival. Furthermore, concurrent inhibition of SMARCA2 and SMARCA4 is fatal to normal cells. Therefore, it holds great therapeutic promise to treat SMARCA4 deficient cancers with selective SMARCA2 degraders while leaving SMARCA4 wild type cells unaffected. Here, we report that SCR-9140 is a high selective SMARCA2 degrader which demonstrates superior anti-tumor activity and low cytotoxicity against non-malignant cells. SCR-9140 strongly degrades SMARCA2 with DC50 of <1 nM and achieves the complete protein degradation (Dmax of >95%) and also shows 100-fold degradation selectivity over SMARCA4 with DC50 of around 100 nM and Dmax of <60% in HiBiT knock-in SW1573 cells. Across a panel of SMARCA4 deficient tumor cell lines, SCR-9140 potently inhibits proliferation with IC50 values ranging from 1 to 50 nM. Due to the high selectivity over SMARCA4, SCR-9140 neither inhibits proliferation of SW1573 (SMARCA2-WT SMARCA4-WT) cells nor NCI-H1581 (SMARCA2-DEL SMARCA4-DEL) cells with IC50s of over 2000 nM. The degraders with poor selectivity of SMARCA2/4 (DC50 ratio: < 10 folds, Dmax of SMARCA4 > 80%) strongly inhibit the SW1573 cells proliferation with IC50s < 100nM, while there are no significant effects on the NCI-H1581 cells ascribing to the absence of targets. Furthermore, SCR-9140 demonstrates weak cytotoxicity on non-malignant cells, such as WI-38 (human lung fibroblast cells), THLE-2 (human liver cells), and human PBMC, rendering it the greater therapeutic window. In a CDX model of NSCLC, SCR-9140 effectively inhibits tumor growth and TGI correlates well with SMARCA2 degradation in tumors. In conclusion, our potent and selective SMARCA2 degrader, SCR-9140 induces strong synthetic lethality in SMARCA4 deficient cells in vitro and in vivo and shows great safety margin in normal cells.

Citation Format: Feng Zhou, Zhiyong Yu, Ruonan Chen, Feng Tang, Peng Gu, Wenqing Yang, Liting Xue, Ping Chen, Renhong Tang. Identification of a high selective SMARCA2 degrader which effectively suppresses the SMARCA4-deficient tumors in vitro and in vivo [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 1137.
Abstract 1212: Horizontal transfer of functional human papillomavirus genes in head and neck squamous cell carcinoma
Authors: Tasoulas Jason , Yarbrough Wendell Gray , Issaeva Natalia
Published: April 2023

Human papillomavirus (HPV) infections are currently associated with more than 70% of oropharyngeal squamous cell carcinomas (OPSCCs). HPV-positive OPSCCs display a distinct biologic behavior and treatment response and thus are now considered a distinct entity than HPV-negative OPSCCs. However, the underlying process of HPV-related OPSCC carcinogenesis is not entirely clear. HPV as a driver of cervical carcinogenesis is well-characterized with identification of a canonical mechanism dependent on HPV DNA integration, loss of HPV E2 gene expression, and increased expression of HPV E6 and E7 oncogenes with no active infection present in malignant lesions. However, whole genome sequencing found no HPV DNA integration in ~25% of HPV-associated OPSCC, suggesting an alternative mechanism of HPV carcinogenesis. Expression of all HPV genes, including self-assembling capsid proteins, in a substantial portion of HPV+ OPSCC, led us to hypothesize that tumors with episomal HPV are capable of transferring HPV genes to surrounding cells and that HPV gene transfer contributes to carcinogenesis in this subset of OPSCC. Our data support this hypothesis, showing that growth media from HPV+ OPSCC cell lines, as well as isolates from HPV+ tumors or nodal metastases, effectively transferred functional HPV genes to cells lacking HPV. The HPV DNA Transferring Agent (HDTA) derived from HPV+ OPSCC contained HPV L1 capsid protein and intact HPV genome protected from DNAase degradation. Initial characterization revealed that anti-L1 antibody blocked gene transfer and that exposure of cells to the HDTA initiated a robust innate immune response in recipient cells. Negative staining of HDTA isolate from metastatic lymph nodes revealed many pleomorphic, electron-dense particles with diameter ranging between 20 and 80nM, with approximately 40% of particles being between 50 and 60nM, consistent with the size of HPV. We propose that development and/or maintenance of OPSCCs depend on continuous production of HDTA capable of transferring HPV genes into neighboring cells. This paradigm of tumorigenesis/maintenance in OPSCC is most likely to apply to cancers lacking HPV integration, but may also apply to tumors with integration, since recent data suggested that integrated HPV may excise from the genome to recreate a transient episomal like structure, even containing cellular DNA. Our findings offer novel insights into oropharyngeal carcinogenesis and suggest targeting HDTA as a new therapeutic strategy for HPV-positive OPSCCs.

Citation Format: Jason Tasoulas, Wendell Gray Yarbrough, Natalia Issaeva. Horizontal transfer of functional human papillomavirus genes in head and neck squamous cell carcinoma [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 1212.