bluuebunny/crossref_metadata_2025 huggingface dataset:
Validation of Genetic Markers Associated with Survival in Colorectal Cancer Patients Treated with Oxaliplatin-Based Chemotherapy
Authors: Park Hanla A. , Seibold Petra , Edelmann Dominic , Benner Axel , Canzian Federico , Alwers Elizabeth , Jansen Lina , Schneider Martin , Hoffmeister Michael , Brenner Hermann , Chang-Claude Jenny
Published: December 2021

Background:

Associations between candidate genetic variants and treatment outcomes of oxaliplatin, a drug commonly used for colorectal cancer patients, have been reported but not robustly established. This study aimed to validate previously reported prognostic and predictive genetic markers for oxaliplatin treatment outcomes and evaluate additional putative functional variants.

Methods:

Fifty-three SNPs were selected based on previous reports (40 SNPs) or putative function in candidate genes (13 SNPs). We used data from 1,502 patients with stage II–IV colorectal cancer who received primary adjuvant chemotherapy, 37% of whom received oxaliplatin treatment. Multivariable Cox proportional hazards models for overall survival and progression-free survival were applied separately in stage II–III and stage IV patients. For predictive SNPs, differential outcomes according to the type of chemotherapy (oxaliplatin-based vs. others) were evaluated using an interaction term. For prognostic SNPs, the association was assessed solely in patients with oxaliplatin-based treatment.

Results:

Twelve SNPs were predictive and/or prognostic at P < 0.05 with differential survival based on the type of treatment, in patients with stage II–III (GSTM5-rs11807, ERCC2-rs13181, ERCC2-rs1799793, ERCC5-rs2016073, XPC-rs2228000, P2RX7-rs208294, HMGB1-rs1360485) and in patients with stage IV (GSTM5-rs11807, MNAT1-rs3783819, MNAT1-rs4151330, CXCR1-rs2234671, VEGFA-rs833061, P2RX7-rs2234671). In addition, five novel putative functional SNPs were identified to be predictive (ATP8B3-rs7250872, P2RX7-rs2230911, RPA1-rs5030755, MGMT-rs12917, P2RX7-rs2227963).

Conclusions:

Some SNPs yielded prognostic and/or predictive associations significant at P < 0.05, however, none of the associations remained significant after correction for multiple testing.

Impact:

We did not robustly confirm previously reported SNPs despite some suggestive findings but identified further potential predictive SNPs, which warrant further investigation in well-powered studies.
Associations of Oral Contraceptives with Mammographic Breast Density in Premenopausal Women
Authors: Yaghjyan Lusine , Smotherman Carmen , Heine John , Colditz Graham A. , Rosner Bernard , Tamimi Rulla M.
Published: December 2021

Background:

We investigated the associations of oral contraceptives (OC) with percent breast density (PD), absolute dense area (DA), nondense area (NDA), and a novel image intensity variation (V) measure in premenopausal women.

Methods:

This study included 1,233 controls from a nested case–control study within Nurses' Health Study II cohort. Information on OCs was collected in 1989 and updated biennially. OC use was defined from the questionnaire closest to the mammogram date. PD, DA, and NDA were measured from digitized film mammograms using a computer-assisted thresholding technique; the V measure was obtained with a previously developed algorithm measuring the SD of pixel values in the eroded breast region. Generalized linear regression was used to assess associations between OCs and density measures (square root–transformed PD, DA, and NDA, and –untransformed V).

Results:

OC use was not associated with PD [current vs. never: β = −0.06; 95% confidence interval (CI), −0.37–0.24; past vs. never: β = 0.10; 95% CI, −0.09–0.29], DA (current vs. never: β = −0.20; 95% CI −0.59–0.18; past vs. never: β = 0.13; 95% CI, −0.12–0.39), and NDA (current vs. never: β = −0.19; 95% CI, −0.56–0.18; past vs. never: β = −0.01; 95% CI, −0.28–0.25). Women with younger age at initiation had significantly greater V-measure (<20 years vs. never: β = 26.88; 95% CI, 3.18–50.58; 20–24 years vs. never: β = 20.23; 95% CI, −4.24–44.71; 25–29 years vs. never: β = 2.61; 95% CI −29.00–34.23; ≥30 years vs. never: β = 0.28; 95% CI, −34.16–34.72, Ptrend = 0.03).

Conclusions:

Our findings suggest that an earlier age at first OC use was associated with significantly greater V.

Impact:

These findings could guide decisions about the age for OC initiation.
DNA Methylation in Peripheral Blood: Providing Novel Biomarkers of Exposure and Immunity to Examine Cancer Risk
Authors: Michaud Dominique S. , Kelsey Karl T.
Published: December 2021

DNA methylation is an epigenetic phenomenon that can alter and control gene expression. Because methylation plays a key role in cell differentiation, methylation markers have been identified that are unique to a given cell type; these markers are stable and can be measured in tissue or whole blood. The article by Katzke and colleagues, published in this issue, uses methylation markers to estimate proportions of immune cell subtypes in peripheral blood samples that were collected prior to diagnosis, thus allowing them to directly examine associations with pancreatic cancer risk. Given that immune-cell counts cannot be measured from archived blood, and that retrospective case–control studies rely on blood that is collected after cancer diagnosis, few studies have been able to examine the role of the systemic immune response in cancer risk. Measurement of DNA methylation in peripheral blood, primarily through development of whole-genome approaches, has also opened new doors to examining cancer etiology.

See related article by Katzke et al., p. 2179
Modulation of the Human Pancreatic Ductal Adenocarcinoma Immune Microenvironment by Stereotactic Body Radiotherapy
Authors: Mills Bradley N. , Qiu Haoming , Drage Michael G. , Chen Chunmo , Mathew Jocelyn S. , Garrett-Larsen Jesse , Ye Jian , Uccello Taylor P. , Murphy Joseph D. , Belt Brian A. , Lord Edith M. , Katz Alan W. , Linehan David C. , Gerber Scott A.
Published: December 2021

Purpose:

Stereotactic body radiotherapy (SBRT) is an emerging treatment modality for pancreatic ductal adenocarcinoma (PDAC), which can effectively prime cytotoxic T cells by inducing immunogenic tumor cell death in preclinical models. SBRT effects on human PDAC have yet to be thoroughly investigated; therefore, this study aimed to characterize immunomodulation in the human PDAC tumor microenvironment following therapy.

Experimental Design:

Tumor samples were obtained from patients with resectable PDAC. Radiotherapy was delivered a median of 7 days prior to surgical resection, and sections were analyzed by multiplex IHC (mIHC), RNA sequencing, and T-cell receptor sequencing (TCR-seq).

Results:

Analysis of SBRT-treated tumor tissue indicated reduced tumor cell density and increased immunogenic cell death relative to untreated controls. Radiotherapy promoted collagen deposition; however, vasculature was unaffected and spatial analyses lacked evidence of T-cell sequestration. Conversely, SBRT resulted in fewer tertiary lymphoid structures and failed to lessen or reprogram abundant immune suppressor populations. Higher percentages of PD-1+ T cells were observed following SBRT, and a subset of tumors displayed more clonal T-cell repertoires.

Conclusions:

These findings suggest that SBRT augmentation of antitumor immunogenicity may be dampened by an overabundance of refractory immunosuppressive populations, and support the continued development of SBRT/immunotherapy combination for human PDAC.
Safety, Activity, and Long-term Outcomes of Pomalidomide in the Treatment of Kaposi Sarcoma among Individuals with or without HIV Infection
Authors: Ramaswami Ramya , Polizzotto Mark N. , Lurain Kathryn , Wyvill Kathleen M. , Widell Anaida , George Jomy , Goncalves Priscila , Steinberg Seth M. , Whitby Denise , Uldrick Thomas S. , Yarchoan Robert
Published: December 2021

Purpose:

Kaposi sarcoma (KS) is caused by Kaposi sarcoma herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8). KS, which develops most frequently among people with HIV, is generally treated with chemotherapy, but these drugs have acute and cumulative toxicities. We previously described initial results of a trial of pomalidomide, an oral immunomodulatory derivative of thalidomide, in patients with KS. Here, we present results on the full cohort and survival outcomes.

Patients and Methods:

Participants with KS with or without HIV were treated with pomalidomide 5 mg once daily for 21 days per 28-day cycle with aspirin 81 mg daily for thromboprophylaxis. Participants with HIV received antiretroviral therapy. Response was defined by modified version of the AIDS Clinical Trial Group KS criteria. We evaluated tumor responses (including participants who had a second course), adverse events, progression-free survival (PFS), and long-term outcomes.

Results:

Twenty-eight participants were enrolled. Eighteen (64%) were HIV positive and 21 (75%) had advanced (T1) disease. The overall response rate was 71%: 95% confidence interval (CI) 51%–87%. Twelve of 18 HIV-positive (67%; 95% CI, 41–87%) and 8 of 10 HIV-negative participants (80%; 95% CI, 44%–97%) had a response. Two of 4 participants who received a second course of pomalidomide had a partial response. The median PFS was 10.2 months (95% CI: 7.6–15.7 months). Grade 3 neutropenia was noted among 50% of participants. In the follow-up period, 3 participants with HIV had other KSHV-associated diseases.

Conclusions:

Pomalidomide is a safe and active chemotherapy-sparing agent for the treatment of KS among individuals with or without HIV.
Abstract IACICR01: Perspective on bivalent degraders
Authors: Ciulli Alessio
Published: December 2021

Bivalent degrader molecules (also known as PROTACs) recruit proteins to E3 ligases for targeted protein degradation. Formation of a ternary complex between the PROTAC, the E3 and the target leads to the tagging of the target protein by ubiquitination, and subsequent proteasomal degradation.

Over the past 6 years, PROTACs have witnessed significant development and exponential rise in interest and adoption across academia and the biopharma industry, enabled by the discoveries of high-quality, drug-like small-molecule ligands for the E3 ligases cereblon (CRBN) and von Hippel-Lindau (VHL). They are today firmly established both as chemical tools to study biology and as next-generation medicine, with a first wave of PROTAC molecules advancing in clinical trials against cancer and other diseases. Degrading rather than inhibiting a target protein offers a novel modality of chemical intervention, and advantages such as more efficacious drug response at lower doses, and enhanced target selectivity, with potentially reduced side effects and disease resistance.

This lecture will offer a perspective on this rapidly evolving field, from deepened understanding of how PROTACs work, to current trends in their development, including recent expansion beyond bivalency, and an outlook on future directions.

Citation Format: Alessio Ciulli. Perspective on bivalent degraders [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr IACICR01.
Abstract LBA005: Detection of KRAS amplification on extrachromosomal DNA (ecDNA) upon acquired resistance to KRASG12C inhibitors
Authors: Hansen Ryan J , Horton Steven , Wiese Julie , Bibay BellJohn , Mora-Blanco E.Lorena , Nguyen Nam-Phuong , Engstrom Lars D , Briere David M , Calinisan Andres , Olson Peter , Awad Mark M , Aguirre Andrew J , Christiansen Jason , Hassig Christian , Kasibhatla Shailaja
Published: December 2021

The recent discovery and clinical validation of KRAS inhibitors (KRASi) has ushered in a new therapeutic approach to directly address the previously undruggable mutant KRAS-driven cancers. Unfortunately, as with other oncogene-directed therapies, acquired resistance to KRASi has been observed that is partially attributed to secondary mutations in KRAS and/or mutations or fusions in other mitogen-activated protein kinase (MAPK) signaling genes. Emerging evidence suggests that amplification of oncogenes on acentric extrachromosomal DNA (ecDNA) might constitute an important mechanism of rapid resistance to receptor tyrosine kinase (RTK) and MAPK targeting therapies. Therefore, we investigated whether resistance to KRASi monotherapy is mediated through an ecDNA mechanism. We previously noted focal gene amplification of KRAS and MET in recurrent tumors isolated from patients treated with the selective KRASG12C inhibitor, adagrasib. Analysis of next-generation sequencing (NGS) data from a patient tumor revealed evidence of circular DNA structures encompassing the KRAS locus. Consistent with this finding, interphase FISH analysis indicated the presence of KRAS amplifications on ecDNA in this adagrasib-treated patient tumor. To further interrogate this biology, we examined a genetically modified CT26 murine tumor model harboring KRASG12C alteration. Analogous to the clinical observations, both adagrasib as well as the recently approved KRASi sotorasib, induced transient tumor regressions that subsequently resumed growth following several weeks of continuous therapy. Strikingly, whole-genome sequencing data from isolated recurrent tumors revealed focal amplification of KRASG12C and metaphase FISH confirmed high levels of KRASG12C on ecDNA as compared to vehicle-treated samples. Further mechanistic studies are underway. Collectively, these observations implicate ecDNA as an important mediator of resistance to KRASi monotherapy and reinforce the critical need for novel therapeutic strategies to address ecDNA oncogene amplification-driven cancers.

Citation Format: Ryan J Hansen, Steven Horton, Julie Wiese, BellJohn Bibay, E.Lorena Mora-Blanco, Nam-Phuong Nguyen, Lars D Engstrom, David M Briere, Andres Calinisan, Peter Olson, Mark M Awad, Andrew J Aguirre, Jason Christiansen, Christian Hassig, Shailaja Kasibhatla. Detection of KRAS amplification on extrachromosomal DNA (ecDNA) upon acquired resistance to KRASG12C inhibitors [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA005.
Abstract LBA016: Androgen Receptor (AR) N-Terminus-Domain-Binding Small Molecule Degraders for the Treatment of AR Splice Variant-Positive Castration-Resistant Prostate Cancer
Authors: Narayanan Ramesh
Published: December 2021

Prostate cancer is the second leading cause of cancer-related deaths in men in the United States. Over 30,000 men die of prostate cancer each year in the U.S. and the deaths predominantly occur due to late-stage castration-resistant prostate cancer (CRPC). Androgen receptor (AR) is the primary therapeutic target in castration-sensitive prostate cancer and CRPC, with over 85% of the cases expressing AR. About 30% of CRPC fail to respond to ligand-binding domain (LBD)-binding AR-signaling inhibitors, while the remaining develop resistance after an initial period of response of 12-24 months. Expression of AR splice variants (AR-SVs) that lack LBD has been identified as one of the primary causes for resistance development to AR-signaling inhibitors. AR-SVs also promote aggressive CRPC growth, resulting in shorter overall survival. We discovered novel AR N-terminus domain (NTD)-binding small molecule, GTx-534 that induce degradation of AR and AR-SV proteins, resulting in loss of AR signaling. Surface Plasmon Resonance (SPR), intrinsic fluorescence biophysical studies and thermal stability analysis with purified AR activation function-1 (AF-1) domain in the NTD showed GTX-534 binding. Notably, GTx-534 significantly inhibited AR and AR-V7-positive 22RV1 cell line xenograft in castrated immune compromised rodents with a tumor growth inhibition (TGI) of over 50% (p<0.005), while enzalutamide failed to inhibit the 22RV1 tumor growth. Serum PSA concentrations of 22RV1-bearing animals were reduced to background levels by GTx-534 (p<0.01), but not by enzalutamide. Genome-wide expression studies demonstrated a distinct mechanism of action for GTx-534 in AR-SV-positive tumors. The results from 22RV1 xenograft studies were validated in LuCaP 86.2 patient-derived xenograft (PDX) that express AR v567es, another AR variant that lacks the LBD widely expressed in CRPC. GTx-534 completely inhibited LuCaP 86.2 tumor growth with a TGI of greater than 90%, while enzalutamide failed to alter the tumor growth. These results provide preclinical proof-of-concept for the efficacy of GTx-534 in AR and AR-SV-positive CRPC. Disclosure. The work presented in here was funded by a Sponsored Research Agreement from Oncternal Therapeutics, Inc. to RN and DDM and by National Cancer Institute grant R01CA229164 to RN. RN is a consultant to Oncternal Therapeutics Inc. GFK and JBB are employees of Oncternal Therapeutics Inc.

Citation Format: Ramesh Narayanan. Androgen Receptor (AR) N-Terminus-Domain-Binding Small Molecule Degraders for the Treatment of AR Splice Variant-Positive Castration-Resistant Prostate Cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA016.
Abstract LBA025: AXL-STAT3 targeting of lung tumor microenvironments
Authors: Taverna Josephine A.
Published: December 2021

The tumor microenvironment contains multiple cell types, each providing a unique functionality in support of malignant growth. To prepare a pro-metastatic niche, a tight signaling network may be present to coordinate delivery of co-stimulatory signals among different cell subpopulations. Here, we report that AXL signaling collaborates with STAT3 to create a symbiotic ecosystem that favors partial epithelial-mesenchymal transition of cancer cells, pro-tumorigenic remodeling of fibroblasts, and M2 polarization of macrophages. To facilitate intercellular communication, AXL-regulated IL-11 secreted from cancer cells and fibroblasts binds to surface GP130 on macrophages to activate STAT3 signaling for M2 polarization. Disruption of AXL-STAT3 circuit not only compromises this signaling co-dependency in lung cancer cells implanted in xenograft mice, but also limits their ability to conscript murine fibroblasts, macrophages, and other immune cells to form a shared habitat for tumor growth and invasion. Therefore, targeting AXL-STAT3 network is an attractive strategy to render inoperative tumor microenvironments that exploit this cellular synchronicity for tumor progression. Significance: Combined targeting of AXL and STAT3 signaling that facilitates co-dependency between malignant and non-malignant cells in tumor microenvironments is a promising strategy for the treatment of advanced lung adenocarcinomas.

Citation Format: Josephine A. Taverna. AXL-STAT3 targeting of lung tumor microenvironments [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA025.
Abstract LBA034: Necrostatin-1 Protects Ferroptosis by xCT Induction in a RIPK1- and IDO-independent manner
Authors: Abdullah Md , Yuk Hanna , Kim Do Hyung , Lee Haeseung , Lee Seung Jin
Published: December 2021

Ferroptosis is caused by the iron-mediated accumulation of lipid peroxidation, which is distinct from apoptosis and necroptosis. Necrostatin-1 inhibits receptor-interacting ser-ine/threonine-protein kinase 1 (RIPK1) to initiate necroptosis; it also inhibits indoleamine 2,3-dioxygenase (IDO) to regulate tumor immunity. However, few studies have examined the off-target effect of necrostatin-1 on the ferroptosis pathway. The present study examined wheth-er necrostatin-1 could interrupt ferroptosis induced by system xc- inhibitors (sulfasalazine and erastin) and a glutathione peroxidase 4 inhibitor (RSL3) in Huh7 and SK-HEP-1 cells. Necrostatin-1 completely prevented decreases in cell viability induced by sulfasalazine and erastin; it partially blunted decreases in cell viability induced by RSL3. Necrostatin-1, ferrostatin-1, and deferoxamine repressed sulfasalazine-provoked membrane permeabilization, as detected by 7-aminoactinomycin D staining and lipid peroxidation measured using a C11-BODIPY probe. However, other RIPK1 inhibitors (necrostatin-1s and GSK2982772) and an IDO inhibitor (1-methyl-D-tryptophan) did not recover the decrease in cell viability induced by sulfasalazine. Necrostatin-1 potentiated sulfasalazine-induced expression of xCT, a catalytic subunit of system xc- in these cells. These results demonstrated that necrostatin-1 blocked fer-roptosis through a mechanism independent from RIPK1 and IDO inhibition in Huh7 and SK-HEP-1 cells, indicating that its antioxidant activity should be considered when using necrostatin-1 as a RIPK1 inhibitor.

Citation Format: Md Abdullah, Hanna Yuk, Do Hyung Kim, Haeseung Lee, Seung Jin Lee. Necrostatin-1 Protects Ferroptosis by xCT Induction in a RIPK1- and IDO-independent manner [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA034.
Abstract LBA037: Reposition of the antibiotic nitroxoline as a novel STAT3 inhibitor for drug-resistant urothelial bladder cancer
Authors: LIN WENFENG , Sun Jingkai , Sadahira Takuya , Araki Motoo , Watanabe Masami , Nasu Yasutomo , Huang Peng
Published: December 2021

Background: Repeated cycles of first-line chemotherapy drugs such as doxorubicin (DOX) and cisplatin (CIS) trigger frequent chemoresistance in recurrent urothelial bladder cancer (UBC), posing a threat to the prognosis of patients. Nitroxoline (NTX), an antibiotic to treat urinary tract infections, has been recently repurposed for the treatment of multiple tumors. Here we aimed to investigate whether NTX suppresses the growth of drug-resistant UBC in vitro and in vivo and the underlying mechanism at the molecular level. Methods: The drug-resistant cell lines T24/DOX and T24/CIS were established by continual exposure of parental cell line T24 to DOX and CIS, respectively. The drug effects on cell proliferation were measured by XTT assay. Cell cycle distribution was analyzed by PI/RNase staining, while apoptosis was assessed by Hoechst 33342 and Annexin V-FITC/PI staining. The expressions of proteins related to STAT3 signaling, cell cycle, and apoptosis were detected by western blotting. Subcutaneous xenograft models of T24/DOX and T24/CIS were established to determine the in vivo anti-tumor effect of NTX. Results: T24/DOX and T24/CIS cells were resistant to DOX and CIS respectively, but they were sensitive to NTX in a time- and dose-dependent manner. Overexpressions of STAT3 and P-glycoprotein (P-gp) were identified in T24/DOX and T24/CIS, which could be reversed by NTX. Furthermore, western blotting showed that NTX downregulated the expressions of phosphorylated STAT3, c-Myc, Cyclin D1, CDK4, CDK6, Bcl-xL, Mcl-1, and Survivin, which were further confirmed by Stattic, a selective STAT3 inhibitor. In vivo, NTX exhibits the significant anti-tumor effect in T24/DOX and T24/CIS tumor-bearing mice. These results suggested that NTX-induced G0/G1 arrest, apoptosis, and P-gp reversal in drug-resistant UBC were mediated by inhibition of STAT3 signaling. Conclusion: Our findings repurpose NTX as a novel STAT3 inhibitor to induce P-gp reversal, G0/G1 arrest, and apoptosis in drug-resistant UBC.

Citation Format: WENFENG LIN, Jingkai Sun, Takuya Sadahira, Motoo Araki, Masami Watanabe, Yasutomo Nasu, Peng Huang. Reposition of the antibiotic nitroxoline as a novel STAT3 inhibitor for drug-resistant urothelial bladder cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA037.
Abstract LBA048: Lymph node metastasis targeted intranodal delivery of docetaxel improves treatment outcome
Authors: Sukhbaatar Ariunbuyan , Sora Shouta , Shiro Mori , Kodama Tetsuya
Published: December 2021

Despite recent advances in diagnostic modalities and cancer treatment guidelines, systemic chemotherapy for the lymph node (LN) metastasis has poor treatment efficacy using conventional drugs. Therefore, a novel method, lymphatic drug delivery system (LDDS), has been proposed in a pre-clinical experiment that directly injects the anticancer drug into sentinel LNs to deliver into their downstream LNs, aiming to inhibit tumor cell growth in those LNs. The injection duration of chemotherapy drugs using the LDDS will be less than the intratumoral or intralesion methods used in the clinic, and systemic toxicity will be less than tumor-targeted therapy or systemic chemotherapy. Our previous results indicated that the treatment efficacy increased in LDDS treated groups than systemic delivery. Here, we show the improvement of treatment efficacy by increasing osmotic pressure and viscosity of the drug solvent delivered by LDDS using the metastatic LN mouse model. First, a metastatic LN mouse model was created by inoculating luciferase-expressing tumor cells into subiliac LN (SiLN) of MXH10/Mo/lpr mouse to induce metastasis into the proper axillary LN (PALN). Next, 10 mg/kg docetaxel (DTX) with increased osmotic pressure and viscosity were injected into tumor-inoculated SiLN with an injection rate of 2400 μL/min on day 7 post-inoculation to inhibit tumor cell growth in the inoculation and metastatic site. Luciferase activity decreases in PALNs and SiLNs were observed in groups between 1140 kPa, 1960 kPa, and 2780 kPa (4, 11, and 38 mPa·s) groups without inducing any side effects. By histology, no tumor cells were confirmed in those LNs of the 1960 kPa group. Then, DTX at 1960 kPa, 11 mPa·s was injected into tumor-inoculated SiLN on day 21 post-inoculation with different injection speeds and volumes. We found that DTX at 1960 kPa, 11 mPa·s injected at the injection rate of 200 μL/min with 400 μL volume, can inhibit tumor cell growth in the PALN and delay tumor growth SiLN. Furthermore, the antitumor effects depended on the tumor progression stage in the LNs, and the injection rates and volumes of administered drugs. We anticipate these optimal ranges as a starting point for developing more effective drug regimens to treat metastatic LNs with the LDDS. Moreover, administrable drugs in this novel method of ultrasound-guided LDDS or LDDS at intra-operative or image-guided surgery are not limited only to anticancer agents.

Citation Format: Ariunbuyan Sukhbaatar, Shouta Sora, Mori Shiro, Tetsuya Kodama. Lymph node metastasis targeted intranodal delivery of docetaxel improves treatment outcome [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA048.
Abstract P001: The anti-angiogenic antibody BD0801 demonstrates better anti-tumor activity than bevacizumab and synergize with chemotherapies in multiple tumor models
Authors: Xue Liting , Tang Jianxing , Ding Yuyin , Song Lei , Xu Shansen , Huang Yue , Wu Yan , Song Wenjie , Tang Renhong , Yang Wenqing
Published: December 2021

Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) play a fundamental role in tumor growth and angiogenesis. An increasing number of evidences have suggested enhanced anti-tumor activity when combining anti-angiogenic agents with chemotherapies in the clinic. To support the clinical development of BD0801, a humanized rabbit anti-VEGF monoclonal antibody, we assessed anti-tumor activities of BD0801 using a series of preclinical tumor mouse models including human ovarian cancer OVCAR-8 and SK-OV-3, human non-small cell lung cancer (NSCLC) NCI-H460, and human renal cancer Caki-1 models, with bevacizumab being used as a benchmark. We also investigated the pharmacological kinetics (PK) of BD0801 in cynomolgus monkeys. BD0801 or bevacizumab were intravenously injected into tumor bearing mice at 0.8 mg/kg, 2.5 mg/kg or 7.5 mg/kg twice a week. Combinations of chemotherapy and BD0801 or bevacizumab were also investigated in some of the tumor models. BD0801 presented more potent anti-tumor activities than bevacizumab in ovarian cancer, NSCLC and renal cancer mouse models in a dose-dependent manner. The tumor growth inhibition of BD0801 was 2-20%, 34-66%, or 32-84% when dosed at 0.8 mg/kg, 2.5 mg/kg or 7.5 mg/kg, respectively. Besides, combination of 2.5 mg/kg BD0801 and 10 mg/kg paclitaxel presented a statistically stronger antitumor activity in human ovarian cancer models compared to both single treatments (P<0.05). Combination of 2.5 mg/kg BD0801, 10 mg/kg paclitaxel, and 80 mg/kg carboplatin also presented a stronger antitumor activity than BD0801 or chemotherapy alone in the human NSCLC model. In cynomolgus monkeys received a single intravenous injection of BD0801 at 1.5, 5, and 15 mg/kg, the half-life (t1/2) of BD0801 was 39.4-142 h, the clearance (Cl) was 0.321-0.900 mL/h/kg, and the apparent volume of distribution (Vd) was 49.5-64.4 mL/kg. The peak concentrations (Cmax) of BD0801 were proportional to the doses administered. No difference on the PK parameters was observed between female and male monkeys. Taken together, this study has demonstrated BD0801 as a more potent molecule than bevacizumab in some preclinical tumor models, supporting further clinical development plans for BD0801, especially in combination with chemotherapeutics.

Citation Format: Liting Xue, Jianxing Tang, Yuyin Ding, Lei Song, Shansen Xu, Yue Huang, Yan Wu, Wenjie Song, Renhong Tang, Wenqing Yang. The anti-angiogenic antibody BD0801 demonstrates better anti-tumor activity than bevacizumab and synergize with chemotherapies in multiple tumor models [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P001.
Abstract P02-04: BDTX-1535, a CNS penetrant MasterKey inhibitor of common, uncommon and resistant EGFR mutations, demonstrates in vivo efficacy and has potential to treat osimertinib-resistant NSCLC with or without brain metastases
Authors: Lucas Matthew C. , Merchant Melinda S. , O'Connor Matthew , Cook Carl , Smith Sherri , Trombino Anthony , Zhang Wu-Yan , Visiers Irache , Tith Kate , Foroughi Reza , Waters Nigel , Wrona Iwona , Pickard Michael , Eathiraj Sudharshan , Witt Karsten , Roberts Christopher , Humphrey Rachel , Buck Elizabeth
Published: December 2021

NSCLC accounts for approximately 85% of lung cancer cases worldwide. NSCLC harboring EGFR mutations constitutes 10-20% of all lung cancer cases in Europe and North America, and up to 50% of those in Asia. The majority (80-90%) of these mutations are either Exon19del or L858R. Uncommon EGFR mutations, of which G719X, S768I and L861Q are amongst the most frequent, account for 10-20% of EGFR mutations in NSCLC. Additionally, secondary EGFR mutations such as C797S that emerge during treatment with osimertinib occur in ~10% of patients. Current generation EGFR inhibitors with efficacy against common, uncommon and/or resistance mutations are either poorly brain penetrant or do not have broad spectrum activity against multiple mutations. BDTX-1535 is an irreversible, spectrum selective MasterKey inhibitor of common, uncommon and resistance EGFR mutations such as G719X and C797S that occur in NSCLC (IC50<10nM). BDTX-1535 is differentiated from many EGFR inhibitors by its CNS-penetrating properties. BDTX-1535 has a Kpuu, defined as the ratio of the unbound brain tissue concentration over the unbound plasma concentration, of 0.8 in rat. In studies of EGFR Exon19del+C797S, BDTX-1535 achieved pEGFR suppression exceeding 24 hours in vitro and following a single dose in vivo. BDTX-1535 has demonstrated robust tumor growth inhibition and regressions in multiple pre-clinical models, including PDX intracranial models. Thus, BDTX-1535 has potential to treat patients with NSCLC harboring a broad range of mutations, both common and uncommon, as well as those associated with resistance to the current standard of care TKIs. The CNS penetrating properties may help to treat CNS metastases or to prevent them from occurring. BDTX-1535 is currently being evaluated in IND-enabling studies.

Citation Format: Matthew C. Lucas, Melinda S. Merchant, Matthew O'Connor, Carl Cook, Sherri Smith, Anthony Trombino, Wu-Yan Zhang, Irache Visiers, Kate Tith, Reza Foroughi, Nigel Waters, Iwona Wrona, Michael Pickard, Sudharshan Eathiraj, Karsten Witt, Christopher Roberts, Rachel Humphrey, Elizabeth Buck. BDTX-1535, a CNS penetrant MasterKey inhibitor of common, uncommon and resistant EGFR mutations, demonstrates in vivo efficacy and has potential to treat osimertinib-resistant NSCLC with or without brain metastases [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P02-04.
Abstract P057: The ubiquitin-dependent ATPase p97 removes cytotoxic trapped PARP1 from chromatin
Authors: Krastev Dragomir , Li Shudong , Sun Yilun , Pommier Yves , Ramadan Kristijan , Lord Christopher J.
Published: December 2021

Poly-(ADP-ribose) polymerase inhibitors (PARPi) elicit anti-tumour activity in homologous recombination defective cancers by promoting cytotoxic, chromatin-bound, “trapped” PARP1. How cells process trapped PARP1 remains unclear. By exploiting wild-type or trapping-resistant PARP1 transgenes combined with either a rapid immunoprecipitation mass-spectrometry of endogenous proteins (RIME)-based approach or PARP1 Apex2-proximity labelling linked to mass-spectrometry, we generated proteomic profiles of trapped and non-trapped PARP1 complexes. This combined approach identified an interaction between trapped PARP1 and the ubiquitin-regulated p97 ATPase (aka VCP). Subsequent experiments demonstrated that upon trapping, PARP1 is SUMOylated by the SUMO-ligase PIAS4 and subsequently ubiquitinated by the SUMO-targeted E3-ubiquitin ligase, RNF4, events that promote p97 recruitment and p97 ATPase-mediated removal of trapped-PARP1 from chromatin. Consistent with this, small molecule p97 complex inhibitors, including a metabolite of the clinically-used drug disulfiram, CuET that acts as a p97 sequestration agent, prolong PARP1 trapping and thus enhance PARPi-induced cytotoxicity in homologous recombination defective tumour cells and patient-derived tumour organoids. Taken together, these results suggest that p97 ATPase plays a key role in the processing of trapped PARP1 from chromatin and the response of homologous recombination defective tumour cells to PARPi.

Citation Format: Dragomir Krastev, Shudong Li, Yilun Sun, Yves Pommier, Kristijan Ramadan, Christopher J. Lord. The ubiquitin-dependent ATPase p97 removes cytotoxic trapped PARP1 from chromatin [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P057.
Abstract P083: Metastatic NSCLC -Re-challenging with first generation TKI after a drug free holiday after resistance to 3rd generation TKI
Authors: Acharya Suryakanta
Published: December 2021

BACKGROUND Lung cancer is the most common cancer worldwide in males & a good number of patients present with metastatic disease. Though EGFR mutated patients respond to EGFR TKIs, resistance develops ultimately. Overcoming 3rd generation EGFR TKI resistance is a big challenge. METHOD 20 patients of metastatic adenocarcinoma, confirmed with core biopsy & IHC (EGFR positive) were offered Erlotinib initially. Osimertinib was offered to those who developed EGFR TKI resistance due to T790M mutation (10 cases). All 10 patients eventually developed resistance to Osimertinib. All patients were given 3 months drug free holiday & then re-challenged with Erlotinib. RESULT 4 out of 10 (40%) patients responded to the therapy. 6 patients had progression & were managed by systemic chemotherapy & radiation. CONCLUSION Literature shows up to 50% metastatic adenocarcinoma, EGFR positive patients who had developed EGFR TKI resistance to 1st & 3rd generation TKIs, responds to re-challenge with first generation TKI after a drug free holiday. In this series 40% patients responded. This approach should be tried & non-responders can be offered systemic chemotherapy & radiation.

Citation Format: Suryakanta Acharya. Metastatic NSCLC -Re-challenging with first generation TKI after a drug free holiday after resistance to 3rd generation TKI [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P083.
Abstract P086: Identification of pharmacodynamic and sensitivity biomarkers for TACH101, a pan-inhibitor of KDM4 histone lysine demethylase
Authors: Perabo Frank , Yoo Sanghee , Chandhasin Chandtip , Rosario Joselyn Del , Chen Young K. , Filvaroff Ellen , Stafford Jeffrey A. , Quake Stephen , Clarke Michael F.
Published: December 2021

Background: TACH101 is a novel, selective and potent inhibitor of KDM4 in development for advanced cancers. KDM4 plays a key role in epigenetic regulation by removing methyl marks on histone H3K9 and H3K36. Overexpression of KDM4 leads to dysregulation of transcription, cell cycle, and DNA replication/repair processes and has been associated with many cancer types. Methods: Candidate pharmacodynamic (PD) and sensitivity biomarkers for TACH101 were evaluated in vitro and in vivo using cancer cell lines, mouse xenograft models, gene microarrays, ChIP-seq, and ChIP-qPCR. Results: Evaluation of differential gene expression from tumor tissue identified several candidates as potential PD markers for TACH101 activity. In particular, direct binding of KDM4 to Protein Phosphatase 1 Regulatory subunit 10 (PPP1R10 or PNUTS) was confirmed by ChIP-seq in cell lines from esophageal (KYSE-150), breast (MDA-MB-231) and lymphoma (OCI-Ly19) cancers. TACH101 treatment caused 86% repression of PNUTS mRNA, as well as a 51% increase in H3K9me3, a mark of repressed transcription. A 78% decrease in H3K36me3 at the PNUTS gene was also observed. PNUTS as a target of KDM4 was validated via ChIP-qPCR in xenograft tumors of KYSE-150, OCI-Ly19 and SU-60 (colorectal). In vivo, maximum inhibition of PNUTS was reached at 8 hours post TACH101 administration, when TACH101 concentration was 100-200 nM in tumors. In addition, extensive bioinformatics analysis using >300 cancer cell lines showed that cell lines with MSI-high (MSI-H) status tended to be more sensitive to TACH101 in vitro. This association was found with other markers of MSI-H status such as MMR gene mutations, MLH1 methylation status, and overall mutation frequency. To further test this association, TACH101 was evaluated in a panel of patient-derived xenograft (PDX) and organoid models. The results showed a strong correlation of TACH101 sensitivity with MSI-H status (IC50 ranges 1-150 nM). Conclusions: Candidate PD biomarkers of TACH101 activity for clinical evaluation have been identified and further studies are ongoing to explore current and additional markers. In addition, MSI-H status was associated with increased sensitivity to TACH101, which may be useful for enriching for select patient populations in clinical studies.

Citation Format: Frank Perabo, Sanghee Yoo, Chandtip Chandhasin, Joselyn Del Rosario, Young K. Chen, Ellen Filvaroff, Jeffrey A. Stafford, Stephen Quake, Michael F. Clarke. Identification of pharmacodynamic and sensitivity biomarkers for TACH101, a pan-inhibitor of KDM4 histone lysine demethylase [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P086.
Abstract P092: A novel approach to target drug-resistance in thyroid cancer by regulating Annexin 7 (ANXA7)/p21 axis
Authors: Radhakrishnan Surya , Bera Alakesh , Puthillathu Narayanan , Gana Nahbuma , Subramanian Madhan , Russ Eric , Paria Anubhuti , Paria Swarnarup , Rothwell Stephen , Pollard Harvey B. , Srivastava Meera
Published: December 2021

Thyroid cancer is the most common endocrine malignancy in the United States. The survival rate of thyroid cancer patients is high. However, there is a group of patients with poor prognosis due to the development of drug resistance. Differential expression and mutation of the BRAF, Met, and p53 genes have been correlated with the progression and aggressiveness of this cancer, and over 60% of thyroid cancer patients were found to have a V600E mutation in BRAF. ANXA7 is a multifunctional protein that has been found to act as a tumor suppressor in many cancers. In this study, we focused on the expression of ANXA7 in relation to the BRAF mutation and its functional role in regulating thyroid cancer progression, aggressiveness, and drug-sensitivity. High-throughput RNA-seq and protein array studies indicated a lower ANXA7 protein expression linked with thyroid cancer. Additionally, ANXA7 was found to be lower in the thyroid cancer cell lines with the BRAF mutation. To test ANXA7’s role in regulating drug-sensitivity, thyroid cancer cells were treated with different BRAF and MEK inhibitors. Both groups of inhibitor treatment on the thyroid cancer cells resulted in an increase in ANXA7 expression, a decrease in Ph-ERK, and an increase in apoptotic markers. We also found that the cyclin-dependent kinase inhibitor p21 is a novel regulator of BRAF mediated chemoresistance, and elevation of both p21 and ANXA7 through the combination of drugs resulted in a synergistic effect in the apoptotic pathway. Together, these results provide new insights into thyroid malignancy and its drug resistance mechanism involving the ANXA7/p21/BRAF/MAPK pathway. Future translational-based approaches with high-throughput functional screenings are necessary to develop a novel and effective ANXA7-based therapeutic strategy for thyroid cancer.

Citation Format: Surya Radhakrishnan, Alakesh Bera, Narayanan Puthillathu, Nahbuma Gana, Madhan Subramanian, Eric Russ, Anubhuti Paria, Swarnarup Paria, Stephen Rothwell, Harvey B. Pollard, Meera Srivastava. A novel approach to target drug-resistance in thyroid cancer by regulating Annexin 7 (ANXA7)/p21 axis [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P092.
Abstract P094: Targeted sequencing revealed clonal genetic changes in spatially different foci in urothelial carcinoma of bladder
Authors: Ugurlu M. Talha , Goldberg Rachel , Sadhukhan Pritam , Hoque Mohammad O.
Published: December 2021

Urothelial Carcinoma of Bladder (UCB) is a disease of multiple origins of the same bladder with varying in morphology and genetic changes. The origin of spatially different tumors in the same bladder has been proposed to occur through clonal changes with intraluminal migration or field effect with synchronous transformation of multiple cells by carcinogens. A clear molecular understanding of the origin of multifocal UCB will have important implications for the proper tailoring of personalized targeted treatment and diagnostics. Despite efforts to identify intertumoral heterogeneity, the clonal origin of UCB is still debated. To further understand the genetic mechanism behind the multifocality of UCB, we performed targeted next-generation sequencing (tNGS) on 39 UCB lesions obtained from 15 cystectomized bladders. Germline distant muscle DNA was used as a control. We technically validated selected mutational events by using ultra-sensitive droplet digital PCR (ddPCR). Our data showed that multifocal UCB is of clonal origin, with lesions from individual patients displaying nearly identical mutational landscapes, with few heterogeneous events that may have been acquired at a later point. tNGS demonstrated similar genetic drivers within the same patient and reveal that clonal expansion is an early event of tumorigenesis. In addition, we found distinct gene mutations in different UCB patients suggesting prominent interpatient heterogeneity of clonal events in the UCB. Among others, our result showed that TP53, FGFR3, and NOTCH4 are the most frequently mutated genes in UCB samples. ddPCR assay of mutational events on TP53, FGFR3, AKT, PIK3CA genes confirmed TNGS data and solidified that mutation in TP53, FGFR3, AKT, PIK3CA genes are associated with tumorigenesis of uroepithelium. In summary, this study conveys insight into the clonal origin of multifocal UCB and demonstrates that TNGS is a sensitive and reliable method for interrogating the molecular landscape of UCB. These findings also may inform clinical practice as sequencing of a single focus from a patient presenting with the multifocal disease may be sufficient to understand the mutational profile and guide personalized treatment and risk stratification.

Citation Format: M. Talha Ugurlu, Rachel Goldberg, Pritam Sadhukhan, Mohammad O. Hoque. Targeted sequencing revealed clonal genetic changes in spatially different foci in urothelial carcinoma of bladder [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P094.