HPAF-II Cells Research Articles

Synergistic inhibition of CXCL8 following MRTX1133 treatment with ONC212 or 5-FU in KRAS G12D and G12V mutant CRC and PDAC cell lines.

e15196 Background: CXCL8, serves as a crucial multifunctional cytokine that plays a significant role in regulating tumor growth, invasion, and migration. Although in some cancers the critical role of CXCL8 in patient prognosis and disease progression is stablished but its role in CRC & PDAC patients is under investigation. High levels of CXCL8 in tumor microenvironment (TME) and association with cancer stem cell survival, immune surveillance escape & metastasis make it an interesting therapeutic target. Both CRC & PDAC are among the deadliest cancers with dismal prognosis. The need for novel therapeutics with a focus on TME is emerging. MRTX1133 was identified as an inhibitor of KRASG12D. ONC212 is a fluorinated imipridone with strong anti-cancer activity in nM range and preclinical efficacy against pancreatic and other malignancies. Here we report the synergistic inhibition of CXCL8 in both KRAS G12D & KRAS G12V cell lines with use of KRAS G12D inhibitor in combination with 5-FU or ONC212. Methods: Different CRC & PDAC cells were treated with MRTX1133 with 5-FU or ONC212 cytokine profiling at 48h time point was done. Human protein atlas was used for protein and RNA data &TCGA data for survival was used. Results: We previously have shown the synergistic inhibition of pERK and cytokine alteration between MRTX1133 KRAS G12D inhibitor with 5FU or ONC212 in both cell lines with KRAS G12D & KRAS G12V mutation (Tajiknia V et al. AACR 2023 annual meeting). In LS513 KRAS G12D CRC cell line, treatment of ONC212, MRTX1133 and combination of both showed a decrease of 52.36%,58.83% and 71.65% respectively in CXCL8 levels compared to control at 48h time point. In HPAF-II KRAS G12V PDAC cell line, treatment of ONC212, MRTX1133 and combination of both resulted in 38.69%, 64.44%, 57% inhibition of CXCL8 levels respectively compared to control. In SW480 KRAS G12V CRC cell line, treatment of ONC212, MRTX1133 and combination of both demonstrated 25.7%,47.3% and 66.5% inhibition in CXCL8 level respectively compared to control at 48h time point. Single treatment of MRTX1133 caused a decline in CXCL8/IL-8 levels by 30% while single treatment of 5-FU showed a 36% decrease, the combination of both resulted in more than 55% decrease compared to control in LS513 KRAS G12D cell line. In SW480 KRAS G12V cell line, combination of 5-FU & MRTX1133 showed 30% inhibition while in Capan-2 PDAC KRAS G12V cells the same combination showed a 48.2% reduction in CXCL8 compared to control at 48h time point. TCGA data for RNA shows low specificity of CXCL8 for cancer type but it is significantly high in CRC and PDAC. Protein concentration in the Pan-cancer cohort shows significant high level of CXCL8 in CRC. Conclusions: Considering the important role of KRAS mutations and CXCL8 in pathogenesis of CRC & PDAC, the effective inhibition of CXCL8 with the use of targeted therapy in combination could enhance treatment response and patient survival.

Abstract LB192: AGR2 knockdown reduces cell proliferation and increases endoplasmic reticulum proteotoxic stress in pancreatic cancer

Abstract Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal solid malignancy with low survival rates due to a dense stroma, abnormal gene expression patterns, and limited treatment options. Anterior gradient 2 (AGR2) is often overexpressed in many cancers, including PDAC. AGR2 belongs to the protein disulfide isomerase family of proteins and is located in the endoplasmic reticulum, where it helps with protein-disulfide isomerase reactions to ensure proper protein folding. However, the molecular mechanisms underpinning AGR2 overexpression in PDAC pathophysiology are not well understood. Gene expression data obtained from the pancreatic adenocarcinoma (PAAD) dataset shows that AGR2 is overexpressed in PDAC tumors compared to normal tissues. We confirmed this gene over-expression in PDAC tumors and multiple pancreatic cancer cell lines using fluorescent microscopy, RT-qPCR, and western blotting. Using stable inducible short hairpin (shRNA) technology, we showed that AGR2 knockdown significantly decreases the viability and colony-forming ability of HPAF-II and PANC-1 cells. Gene Ontology (GO) enrichment analysis revealed that AGR2 knockdown suppresses a host of protein biosynthesis pathways, including protein targeting and localization to the endoplasmic reticulum (ER). Significantly, ER stress was induced in knockdown cells, shown by the activation of unfolded protein response, suggesting an accumulation of unfolded proteins. To determine the effects of unfolded protein accumulation on the ER, we performed transmission electron microscopy. Here, the results show an increase in the ER lumen size of knockdown cells compared to controls. Interestingly, we observed a decrease in mitochondria size and confirmed the increased expression of mitochondria fission proteins DRP1 and MFF. Finally, flow cytometry analysis revealed increased apoptosis in AGR2 knockdown cells compared to controls. Overall, our data provide insights into the role of AGR2 in PDAC tumorigenesis. However, more research is warranted to determine if AGR2 could be a potential therapeutic target. Citation Format: Philip Salu, Katie Reindl. AGR2 knockdown reduces cell proliferation and increases endoplasmic reticulum proteotoxic stress in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB192.

Abstract 944: Pre-clinical activity of the Wnt pathway inhibitor RXC004 in combination with MAPK pathway inhibitors in GI cancer models

Abstract Background: Gastrointestinal (GI) cancers cause more cancer deaths than any other body system, with 3.4 million related deaths in 2018. Wnt pathway activation is common in GI cancers, with the pathogenic upstream Wnt pathway variant sub-population (RNF43 loss of function/RSPO gain of function) showing a combined prevalence of 4.7% in GI cancer patients; pre-clinically this sub-population shows exquisite sensitivity to RXC004, a small molecule Porcupine inhibitor. A striking co-occurrence of upstream Wnt pathway variants with MAPK pathway driver mutations (KRAS, BRAF, NRAS) was detected in 77% of Microsatellite stable (MSS) GI cancers, suggesting co-inhibiting these pathways could enhance clinical activity in these patients. Methods: In vitro proliferation assays were performed in pre-clinical models of upstream Wnt pathway mutated MSS GI cancer (SNU-1411, HPAF-II and AsPC-1) using Wnt (RXC004) or MAPK (Trametinib) pathway inhibitors at multiple concentrations as single agents or in combination. Control cells with downstream Wnt pathway mutations (WiDr and HCT116) were also tested. Synergistic combination effects were detected by BLISS scores. RXC004 (1.5mg/kg QD) and Trametinib (0.3mg/kg QD) were evaluated in an RSPO-fusion xenograft model (SNU-1411) as single agents or in combination. Efficacy was measured by tumour volume and weight; PD markers were assessed in end of study tumour samples. Relative AXIN2 and DUSP6 gene expression changes were determined upon inhibitor treatment by quantitative Polymerase Chain Reaction (qPCR). Results: RXC004 in combination with Trametinib demonstrated strong anti-proliferative synergy in SNU-1411 cells and moderate synergy/additivity in HPAF-II and AsPC-1 cells; no synergy was observed in control cells. In vivo, RXC004 and Trametinib monotherapy led to significant moderate tumour growth control (p<0.05) at the doses tested, whereas their combination led to significantly enhanced efficacy (p<0.05). Gene expression analysis demonstrated a reciprocal Wnt/MAPK signaling mechanism; RXC004 strongly suppressed Wnt signaling (AXIN2) but increased MAPK signaling (DUSP6), whilst Trametinib strongly suppressed MAPK signaling (DUSP6) but increased Wnt signaling (AXIN2). Combination of RXC004 and Trametinib sustained inhibition of both Wnt and MAPK signalling. Similar effects were observed with inhibitors of other MAPK pathway components. Conclusion: Wnt and MAPK pathways are frequently co-activated in GI cancers, particularly in the upstream Wnt pathway mutated sub-population. Pre-clinically we show that Wnt and MAPK pathways act as potential reciprocal resistance mechanisms following single agent inhibition of either pathway; co-inhibition of these pathways leads to synergistic effects in vitro and enhanced efficacy in vivo. This provides a clear rationale to assess this combination approach in the clinic. Citation Format: Simon A. Woodcock, Dorottya Keppel, Catherine Eagle, James Kelly, Eimear Flanagan, Emma Bishop, Inder Bhamra, Clifford D. Jones, Richard Armer, Jane Robertson, Caroline Phillips. Pre-clinical activity of the Wnt pathway inhibitor RXC004 in combination with MAPK pathway inhibitors in GI cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 944.

Abstract 1530: Tumor cell line-derived xenograft subtype shapes tumor microenvironment composition in BRGSF-HIS mice

Abstract The relevance of preclinical models has vastly improved with mice bearing a human immune system, especially in the context of immunotherapy. BRGSF (Balb/C Rag2−/−, IL2Rγ−/−, SIRPαNOD and Flt3−/−) is a highly immunodeficient mouse featuring reduced murine myeloid cells. BRGSF mice reconstituted with human cord blood CD34+ cells (BRGSF-HIS) develop functional lymphoid and myeloid compartments. This engraftment is stable for over a year (Labarthe et al., 2019) and mice do not develop GvHD. Myeloid compartment can be transiently boosted with exogenous human Flt3L injections. In contrary to other models overexpressing human cytokines to develop human myeloid cells, Flt3L-treated BRGSF-HIS mice do not show side effects. BRGSF-HIS mice are permissive to mouse and human cancer cell lines engraftment and represent a valuable preclinical model to study cancer development and test novel therapeutics. Effect of Flt3L-induced boost on myeloid compartment is seen in a non-small cell lung cancer (A549) tumor model. A single boost prior to tumor cell inoculation associates with increased tumor-infiltrating T-cells (mainly CD8+ T-cells) and myeloid cells, and reduced tumor-infiltrating NK cells in the tumor microenvironment (TME). Human triple negative cancer cell (TNBC) MDA-MB-231 and human pancreatic adenocarcinoma HPAFII cell lines are widely used in cancer research and drug development. We show that upon implantation in BRGSF-HIS mice, in vivo growth of human cell line-derived xenograft (CDX) is CD34+ donor independent and the TME composition varies according to cell line used. As seen in TNBC patients (Zheng et al., 2021); TME of MDA-MB-231 bearing BRGSF-HIS mice is enriched in myeloid cells, mostly CD206+/CD163+ M2 macrophages. CD163-expressing M2 macrophages represent the main tumor-associated macrophages, and are known to promote breast cancer initiation, angiogenesis, invasion, and metastasis by generating an immunosuppressive TME. Interestingly, TME composition evolves over time, with increased T cells frequency in later stage (tumor volume over 1000 mm3 compared to 500 mm3) depicting cancer cell plasticity. Conversely, TME of HPAFII bearing mice is mainly composed of T cells enabling T cells-based therapy. Treatment of BRGSF-HIS mice bearing HPAFII tumor cells with combotherapy based on CD3xTAA + CD28xTAA efficiently reduces tumor growth in vivo compared to vehicle-treated mice or mice injected with CD3xTAA alone. Induced systemic immunomodulation is observed in the TME where increased numbers of both CD4 and CD8 T cells are observed upon combotherapy. Remarkably, while no CD34+ donor effect is observed in CDX growth kinetic, response to treatment appears to be donor dependent with apparition of “weak” and “good” responders. This heterogeneity of response mimics what is observed in clinic and enables further investigations of treatment mode of action and immune escape mechanisms. Citation Format: Perrine Martin-Jeantet, Siham Hedir, Fabiane Sonego, Gaëlle Martin, Yacine Cherifi, Kader Thiam. Tumor cell line-derived xenograft subtype shapes tumor microenvironment composition in BRGSF-HIS mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1530.

Abstract C076: New insights into the role of FOXA1- HNF4 axis in pancreatic cancer

Abstract Despite recent advances in the treatment of pancreatic adenocarcinoma (PDAC), the median survival remains <12 months. Patients typically present with late-stage disease and have limited treatment options. Therefore, there is an immediate need for the generation of new and innovative therapeutic targets. Little is known about the role of pioneer factors such as FOXA1 and their interaction partners in a PDAC context. Inspired by literature reports implicating FOXA1 and GATA5/GATA6 in regulating pancreatic cancer resistance and metastasis, our study hypothesised the possibility of an undiscovered nuclear receptor that works with FOXA1 (similar to Estrogen receptor in breast cancer). Using innovative ‘omic’ based approaches (RIME) developed in our laboratory 1 we discovered a nuclear receptor (NR) complex involving HNF4A and HNF4G in the classical sub-type of pancreatic cancer. Subsequently the interaction was independently validated in Whipple surgical biopsies from PDAC patients using ChIP-sequencing studies. Across multiple patient tumors (n=7) a binding overlap specifically between FOXA1 and HNF4G (3461 sites) was established. To investigate the therapeutic potential of HNF4G in the classical subtype of PDAC, we generated CRISPR deletions (KO) of HNF4G in the HPAF-II cells. HNF4G-KO cells were orthotopically implanted into the pancreas of NSG mice. A significant survival advantage of 12 days (<0.001) and reduced growth (<0.02) was observed in these mice compared to the controls. To better understand the impact of HNF4G-KO on gene expression, the orthotopic tumors were subjected to RNA-seq analyses. Gene set enrichment and pathway analysis revealed significantly down-regulated pathways to include EMT transition. TCGA data highlighted HNF4G amplification in 9% of PDAC patients with concomitant decreased progression free survival. These data point towards HNF4G being a therapeutically viable target for further exploration. Protein Arginine Methyl Transferase 1 (PRMT1) is a common interactor of both FOXA1 and HNF4G. Our study reveals a unique dependency of PRMT1 on the HNF4G-FOXA1 complex in PDAC biopsies. HNF4G-KO drastically reduces the chromatin binding of PRMT1, implicating them as functionally dependent. Treatment of HNF4G-KO cells with GSK3368715 (PRMT1 inhibitor) further sensitizes these cells and results in a significant survival advantage (10 days <0.02). We propose a model of HNF4G inhibition in combination with PRMT1 as a novel therapeutic opportunity to treat the classical sub-type of PDAC. Further, our study reveals a unique reliance of primary classical tumors on HNF4G. Although HNF4G appears to dominate FOXA1 functionality in the primary disease, FOXA1 remains instrumental in priming metastasis and enhancer reprograming. 1. Papachristou EK, Kishore K, Holding AN, Harvey K, Roumeliotis TI, Chilamakuri CSR, et al. A quantitative mass spectrometry-based approach to monitor the dynamics of endogenous chromatin-associated protein complexes. Nature Communications. 2018;9(1):2311. Citation Format: Shalini V. Rao, Lisa Young, Danya Cheeseman, Stephanie Mack, Jill Temple, Chandra Shekar Reddy Chilamakuri, Evangelia Papachristou, Catherina Pelicano, Amy Smith, Dominique-Laurent Couturier, Michael Gill, Duncan Jodrell Jodrell, Alasdair Russell, Igor Chernukhin, Jason Carroll. New insights into the role of FOXA1- HNF4 axis in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr C076.

Abstract C088: Preclinical synergistic combination therapy of lurbinectedin with irinotecan and 5-fluorouracil in pancreatic cancer

Abstract Pancreatic cancer is a devastating disease with an overall five-year survival rate of ~12% according to the American Cancer Society. Novel chemotherapeutics and targeted therapies in pancreatic cancer have shown limited success, illustrating the urgent need for new treatments. Lurbinectedin (PM01183; LY-01017) received accelerated FDA approval in 2020 for metastatic small cell lung cancer on or after platinum-based chemotherapy and is currently undergoing clinical trials in a variety of tumor types. Lurbinectedin is a chemotherapeutic synthetic tetrahydroisoquinoline alkaloid that inhibits active transcription by binding to guanine rich sequences in the minor groove of DNA. Lurbinectedin has been shown to reduce oncogenic transcription by stalling and degrading RNA Polymerase II and inducing breaks in DNA, causing subsequent apoptosis. We now demonstrate lurbinectedin’s highly efficient killing of pancreatic tumor cells as a single agent in PANC-1, BxPC-3, and HPAF-II cell lines, with 72-hour IC-50s ranging from 0.266 – 0.964 nM. We further demonstrate that a combination of lurbinectedin and irinotecan, a topoisomerase I inhibitor with FDA approval for advanced pancreatic cancer, results in synergistic killing of pancreatic tumor cells in vitro. Synergism was calculated using SynergyFinder, with HSA scores exceeding 15 in every cell line (synergy scores greater than 10 are considered synergistic according to the website manufacturer). Western Blot analysis of combination therapy indicates an upregulation of γH2AX and ATR, indicating DNA damage likely plays a role in the synergistic effects of the drugs. Bcl-2 downregulation in combination therapy indicates that the Bcl-2 family proteins likely play a role in the apoptosis of the cancer cells. Cytokine profiling analysis indicates an upregulation of the Fas apoptosis-inducing ligand under lurbinectedin and irinotecan monotherapy and combination therapy. VEGF and prolactin were downregulated in combination therapy. We further demonstrate that the triple combination between lurbinectedin, irinotecan, and 5-Fluorouracil (5-FU) enhances % inhibition as each drug concentration increases, and the presence of lurbinectedin enhances the synergism between irinotecan and 5-FU. Our results are developing insights regarding molecular mechanisms underlying therapeutic efficacy of a novel combination drug treatment for pancreatic cancer. Citation Format: Tej Tummala, Arielle De La Cruz, Ash Uruchurtu, Nicholas R. Liguori, Abbas E. Abbas, Leiqing Zhang, Chistopher G. Azzoli, Lanlan Zhou, Wafik S. El-Deiry. Preclinical synergistic combination therapy of lurbinectedin with irinotecan and 5-fluorouracil in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr C088.

Abstract B026: Preclinical synergistic combination therapy of lurbinectedin with irinotecan and 5-fluorouracil in pancreatic cancer

Abstract Pancreatic cancer is a devastating disease with an overall five-year survival rate of ~12% according to the American Cancer Society. Novel chemotherapeutics and targeted therapies in pancreatic cancer have shown limited success, illustrating the urgent need for new treatments. Lurbinectedin (PM01183; LY-01017) received accelerated FDA approval in 2020 for metastatic small cell lung cancer on or after platinum-based chemotherapy and is currently undergoing clinical trials in a variety of tumor types. Lurbinectedin is a chemotherapeutic synthetic tetrahydroisoquinoline alkaloid that inhibits active transcription by binding to guanine rich sequences in the minor groove of DNA. Lurbinectedin has been shown to reduce oncogenic transcription by stalling and degrading RNA Polymerase II and inducing breaks in DNA, causing subsequent apoptosis. We now demonstrate lurbinectedin’s highly efficient killing of pancreatic tumor cells as a single agent in PANC-1, BxPC-3, and HPAF-II cell lines, with 72-hour IC-50s ranging from 0.266 – 0.964 nM. We further demonstrate that a combination of lurbinectedin and irinotecan, a topoisomerase I inhibitor with FDA approval for advanced pancreatic cancer, results in synergistic killing of pancreatic tumor cells in vitro. Synergism was calculated using SynergyFinder, with HSA scores exceeding 15 in every cell line (synergy scores greater than 10 are considered synergistic according to the website manufacturer). Western Blot analysis of combination therapy indicates an upregulation of γH2AX and ATR, indicating DNA damage likely plays a role in the synergistic effects of the drugs. Bcl-2 downregulation in combination therapy indicates that the Bcl-2 family proteins likely play a role in the apoptosis of the cancer cells. Cytokine profiling analysis indicates an upregulation of the Fas apoptosis-inducing ligand under lurbinectedin and irinotecan monotherapy and combination therapy. VEGF and prolactin were downregulated in combination therapy. We further demonstrate that the triple combination between lurbinectedin, irinotecan, and 5-Fluorouracil (5-FU) enhances % inhibition as each drug concentration increases, and the presence of lurbinectedin enhances the synergism between irinotecan and 5-FU. Our results are developing insights regarding molecular mechanisms underlying therapeutic efficacy of a novel combination drug treatment for pancreatic cancer. Citation Format: Tej Tummala, Arielle De La Cruz, Ash Uruchurtu, Nicholas R Liguori, Abbas E Abbas, Leiqing Zhang, Christopher Azzoli, Lanlan Zhou, Wafik S El-Deiry. Preclinical synergistic combination therapy of lurbinectedin with irinotecan and 5-fluorouracil in pancreatic cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B026.

FOLFIRINOX-loaded immunoliposome-like particles for localized pancreatic cancer treatment

FOLFIRINOX therapy, a combination of oxaliplatin, 5-fluorouracil, irinotecan, and leucovorin, is one of the most applied treatment schemes for pancreatic adenocarcinoma. However, because this form of treatment causes significant side effects, it has become important to reduce the dose of the drug administered to the patients and target the drug to the tumor tissue. This study presents the liposomal type of this therapy scheme to demonstrate its applicability to localized chemotherapy strategies. Briefly, lipid-based liposome-like particles have been synthesized and physically, chemically, and thermally characterized. Following the decoration of the liposome-like particles with anti-Mucin-4, a malignancy marker for pancreatic adenocarcinoma, the encapsulation efficiency of the FOLFIRINOX components and release profile of the FOLFIRINOX-loaded liposome-like particles have been analyzed using the high-pressure liquid chromatography. Cytotoxicity analyses and cellular encapsulation studies of Mucin-4-targeted liposome-like particles were performed in HPAF-II (ascites-derived cell, Mucin-4(+)) and PANC-I (tumor-derived cell, Mucin-4(−)) cells. The results have shown that Mucin-4-targeted liposome-like particles enter HPAF-II cells more selectively than PANC-I cells. Besides, after the FOLFIRINOX application, a significant difference was observed between the viability of HPAF-II and PANC-I cells at 100-fold dilution. In genotoxicity and apoptosis analysis, it was found that drug-loaded liposome-like particles caused DNA damage in cancer cells with the increase in concentration. The study suggests that Mucin-4-targeted liposome-like particles can provide superior patient welfare and a promising treatment model for pancreatic adenocarcinoma and can be used in localized chemotherapy applications due to their long-term stability, nanoscale size, and target-driven nature.

Abstract 2674: Synergistic combinations of lurbinectedin with irinotecan and ONC212 in pancreatic cancer

Abstract Pancreatic cancer is a devastating disease with a five-year survival rate below 10% according to the American Cancer Society. Novel chemotherapeutics and targeted therapies in pancreatic cancer have shown limited success, illustrating the urgent need for new treatments. Lurbinectedin is a chemotherapeutic synthetic tetrahydroisoquinoline alkaloid that inhibits active transcription by binding to guanine rich sequences in the minor groove of DNA. Lurbinectedin has been shown to reduce oncogenic transcription by stalling and degrading RNA Polymerase II while also inducing single- and double-stranded breaks to DNA, causing subsequent apoptosis. Lurbinectedin received accelerated FDA approval in 2020 for metastatic small cell lung cancer on or after platinum-based chemotherapy and is currently undergoing clinical trials in a variety of tumor types. We recently described a synergistic interaction between lurbinectedin and ONC201/TIC10, a compound that induces the TRAIL pathway, in killing SCLC cell lines associated with activation of p-Chk1 and the integrated stress response. We now demonstrate lurbinectedin’s efficient killing of pancreatic tumor cells as a single agent in PANC-1, BxPC-3, and HPAF-II cell lines, with IC-50s corresponding to sub-nanomolar concentrations. We also demonstrate that a combination of lurbinectedin and irinotecan, a topoisomerase I inhibitor with FDA approval for advanced pancreatic cancer, results in synergistic killing of pancreatic tumor cells in vitro. We further demonstrate a combination of lurbinectedin and ONC212, an imipridone, the same class of compounds as ONC201, also results in synergistic killing of pancreatic tumor cells. Cell viability was measured using the CellTiterGlo assay at varying drug concentrations. We hypothesize a combination therapy of lurbinectedin and irinotecan or ONC212 can enhance immune cell killing of pancreatic tumor cells. This is being explored by co-culturing CD8+ T lymphoblast cells with pancreatic tumor cells treated with lurbinectedin, irinotecan, ONC212, and combination, along with molecular mechanisms of cell death and effects on cytokines in the tumor microenvironment. Our results are developing insights regarding molecular mechanisms underlying therapeutic efficacy of a novel combination drug treatment for pancreatic cancer. Citation Format: Tej Tummala, Arielle De La Cruz, Ash Uruchurtu, Nicholas R. Liguori, Abbas E. Abbas, Leiqing Zhang, Christopher G. Azzoli, Lanlan Zhou, Wafik S. El-Deiry. Synergistic combinations of lurbinectedin with irinotecan and ONC212 in pancreatic cancer [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 2674.

Abstract P005: SLC38A5 characterization and its tumor promoting role in pancreatic ductal adenocarcinoma

Abstract Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal and aggressive cancers. Based on the Human Protein Atlas database, solute carrier 38A5 (SLC38A5) is significantly upregulated in PDAC and correlates with poor patient survival. SLC38A5 is a Na+-coupled, electroneutral amino acid transporter that transports glutamine, serine, glycine, and methionine that are essential for glutaminolysis and one-carbon metabolism pathways on which cancer cells are dependent. Furthermore, SLC38A5 is a c-Myc target and induces macropinocytosis. Thus, these attributes of SLC38A5 in cancer cells makes it a favorable contribution to their tumor-promoting gene expression programs. Using real-time PCR and Western blotting, we validated the expression status of SLC38A5 in PDAC cell lines, patient derived xenografts (PDX), and organoids. Using radiolabeled serine uptake, we also confirmed that PDAC cell lines express functional SLC38A5. To investigate the tumor promoting role of SLC38A5, shRNA-mediated knockdown of SLC38A5 was performed in BxPC-3 and HPAF-II human PDAC cell lines. After validating SLC38A5 knockdown using real-time PCR and radiolabeled serine uptake, colony formation and transwell invasion assay were performed using the knockdown cells and non-targeting controls (NTC). Interestingly, SLC38A5 knockdown suppressed the colony formation ability as well as the invasion capacity in both cell lines, suggesting the tumor promoting role of SLC38A5. To extrapolate the in vitro data further, we performed subcutaneous xenograft using SLC38A5-silenced BxPC-3 and HPAF-II cells into the athymic nude mice. Interestingly, we found that SLC38A5 knockdown cells grew slower, as evidenced by smaller tumor weight, further validating our in vitro data. Our future work involves extrapolating these data in the KPC (Kras, p53, and PDX-1-Cre) spontaneous mouse model of PDAC and elucidating its mechanism of upregulation. Citation Format: Tyler J. Sniegowski, Vadivel Ganapathy1, Yangzom Bhutia. SLC38A5 characterization and its tumor promoting role in pancreatic ductal adenocarcinoma. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr P005.

Synthesis of Fe3O4nanoparticles encapsulated with orange pectin for the treatment of gastrointestinal cancers

The current work reports a unique bio-inspired synthesis of orange derived pectin modified magnetite nanoparticles (Fe3O4NPs). Pectin is a naturally occurring biopolymer containing plethora of polar organofunctions which are exploited in the toxic reagent free modification of biocompatible magnetic NPs and also towards the stabilization of NPs by preventing them from agglomeration. The physicochemical properties of the as-prepared bio-nanocomposite (Fe3O4@Pectin) was analytically investigated through SEM, EDX, TEM, VSM and XRD. The anti-gastrointestinal system cancers and cytotoxic potentials of synthesized NPs against cancer cell lines were assessed. The anti-gastrointestinal system cancers potentials of the NPscould significantly remove (HT-29, HCT 116, Ramos.2G6.4C10, HCT-8 (Colorectal cancer)), (Capan-2, AsPC-1, CFPAC-1, HPAF-II (Pancreatic cancer)), (GC1436, GC1401, AGS, and GC1415 (Gastric cancer)) cell lines by MTT assay. The corresponding IC50 were found as 13, 8, 16, 15, 11, 12, 15, 15, 23, 36, 30, and 23μg/mL against HT-29, HCT 116, Ramos.2G6.4C10, HCT-8, Capan-2, AsPC-1, CFPAC-1, HPAF-II, GC1436, GC1401, AGS, and GC1415 cancer cell lines. Furthermore, the antioxidant capacity of Fe3O4@Pectin NPswas determined by DPPH method which displayeda significant activity as per IC50 value. It is believed that the antioxidant effects play a significant role in the considerable anti-colorectal, pancreatic and gastric cancerseffects.

METTL16 predicts a favorable outcome and primes antitumor immunity in pancreatic ductal adenocarcinoma.

Pancreatic carcinogenesis is a complicated and multi-step process. It is substantially assisted by N6-methyladenosine (m6A) RNA modification, especially when mutations of driver genes (KRAS, TP53, CDKN2A, and SMAD4) occur. However, the underlying mechanism remains obscure. In this research, we identified m6A regulators as potential biomarkers when mutations of driver genes occur, and investigated the role of these m6A candidates in pancreatic ductal adenocarcinoma (PDA). We first estimated the abnormal expression patterns of potential m6A regulators when all the driver genes are mutated, using The Cancer Genome Atlas and Gene Expression Omnibus databases. METTL16, an m6A“writer,” was chosen as a unique candidate of PDA, owing to its markedly differential expression under mutations of all driver genes (KRAS, TP53, CDKN2A, and SMAD4) and its favorable prognostic value. Moreover, METTL16 was under-expressed in PDA tissues and cell lines. Consistently, gain- and loss-of-function experiments indicated that it had a tumor suppressor role in vitro and in vivo. Further, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that METTL16 may have an effect on the tumor microenvironment. Notably, a markedly positive association between METTL16 expression and infiltration of B cells and CD8+ T cells was observed according to the CIBERSORT and TIMER databases. Enhanced expression of immune checkpoints and cytokines was elicited in patients with over-expression of METTL16. Notably, decreased expression of PD-L1 was observed when upregulation of METTL16 expression occurred in MIA PaCa-2 cells, while increased expression of PD-L1 existed when downregulation of METTL16 happened in HPAF-II cells. Collectively, these findings highlight the prognostic value of METTL16, and indicate that it is a potential immunotherapy target that could be used to regulate the tumor microenvironment and promote antitumor immunity in PDA.

A New Oxadiazole-Based Topsentin Derivative Modulates Cyclin-Dependent Kinase 1 Expression and Exerts Cytotoxic Effects on Pancreatic Cancer Cells.

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal form of cancer characterized by drug resistance, urging new therapeutic strategies. In recent years, protein kinases have emerged as promising pharmacological targets for the treatment of several solid and hematological tumors. Interestingly, cyclin-dependent kinase 1 (CDK1) is overexpressed in PDAC tissues and has been correlated to the aggressive nature of these tumors because of its key role in cell cycle progression and resistance to the induction of apoptosis. For these reasons, CDK1 is one of the main causes of chemoresistance, representing a promising pharmacological target. In this study, we report the synthesis of new 1,2,4-oxadiazole compounds and evaluate their ability to inhibit the cell growth of PATU-T, Hs766T, and HPAF-II cell lines and a primary PDAC cell culture (PDAC3). Compound 6b was the most active compound, with IC50 values ranging from 5.7 to 10.7 µM. Molecular docking of 6b into the active site of CDK1 showed the ability of the compound to interact effectively with the adenosine triphosphate binding pocket. Therefore, we assessed its ability to induce apoptosis (which increased 1.5- and 2-fold in PATU-T and PDAC3 cells, respectively) and to inhibit CDK1 expression, which was reduced to 45% in Hs766T. Lastly, compound 6b passed the ADME prediction, showing good pharmacokinetic parameters. These data demonstrate that 6b displays cytotoxic activity, induces apoptosis, and targets CDK1, supporting further studies for the development of similar compounds against PDAC.

Docosahexaenoic Acid Inhibits Cell Proliferation through a Suppression of c-Myc Protein in Pancreatic Ductal Adenocarcinoma Cells.

Treatment of pancreatic cancer by inhibiting the aberrant activation of the survival signaling pathways has received considerable attention. We investigated the probable action of DHA on the suppression of cell proliferation in human pancreatic ductal adenocarcinoma (PDAC) cells. Our results demonstrated that DHA dose-dependently inhibited cell proliferation through an induction of cell cycle arrest in human PDAC cells. DHA suppressed the expression of phosphorylated-Rb (p-Rb), cyclin D1, cyclin E, cyclin A, E2F1 and c-Myc proteins. Blocking the activation of STAT3 signaling pathway led to an inactivation of CAMKII and increased phosphorylation of c-Myc (T58) protein accompanied with decreased expression of c-Myc protein. Treatment of DHA effectively inhibited cell survival through decreased phosphorylation levels of EGFR, STAT3 and CAMKII proteins. The mechanisms of action were associated with increased phosphorylation levels of c-Myc (T58) and instability of c-Myc proteins. DHA inhibited cell survival through an increased GSSG/GSH ratio and oxidative stress level in HPAF-II cells. DHA induced cell apoptosis through increased expression of Bax, c-caspase 3 and c-PARP proteins in HPAF-II cells. Moreover, treatment of DHA significantly inhibited nucleotide synthesis. In conclusion, DHA might significantly suppress the proliferation of PDAC cells and therefore have potential as an anti-cancer therapeutic agent.

Abstract 2329: ONC212-induced impairment of oxidative phosphorylation is synergistic with glycolysis inhibition in treatment of pancreatic cancer in vitro and in vivo

Abstract ONC212 is a fluorinated imipridone shown to have preclinical efficacy against multiple cancers, including pancreatic cancer. One of the binding targets of ONC212 is the mitochondrial peptidase, ClpP, but its role in the anticancer activity of ONC212 is incompletely understood. Understanding the effects of ONC212 on the bioenergetics of pancreatic cancer could facilitate understanding and amplification of its anti-tumor effects. On extracellular flux analysis, ONC212 impairs mitochondrial ATP production and oxidative phosphorylation in multiple pancreatic cancer lines. However, pancreatic adenocarcinoma uses both glycolysis and mitochondrial function to meet its energy demands. Some pancreatic cancer cell lines are resistant to ONC212 inhibition of oxidative phosphorylation alone, but co-treatment with glycolytic inhibitor 2-deoxy-D-glucose (2-DG) synergizes with ONC212 and increases tumor cell death in vitro. Suppression of ClpX, the regulatory binding protein of ClpP, occurs with ONC212 treatment and was used as a biomarker of ONC212 activity. This suppression was demonstrated in multiple pancreatic cancer lines in vitro and in vivo. In a xenograft mouse tumor model of pancreatic cancer using both the ONC212 resistant Bxpc3 pancreatic cancer cell line and the more sensitive HPAF-II cell line, the combination of ONC212 and 2-DG treatment significantly decreased tumor growth and reduced the intertumoral variability. Immunohistochemistry also revealed increased apoptotic markers in these tumors. There was no significant toxicity from dual treatment in mice, which suggests that tumor energy deprivation from dual inhibition of oxidative phosphorylation and glycolysis via ONC212 and 2-DG has a therapeutic window and should be explored further as a potential combination therapy. In addition, if this effect holds true across other models and cancer types, baseline mitoATP percentage could be used as a functional biomarker of sensitivity to ONC212. Citation Format: Anna Donovan Louie, Isacco Ferrarini, Lanlan Zhou, Wafik S. El-Deiry. ONC212-induced impairment of oxidative phosphorylation is synergistic with glycolysis inhibition in treatment of pancreatic cancer in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2329.

SLC45A4 promotes glycolysis and prevents AMPK/ULK1-induced autophagy in TP53 mutant pancreatic ductal adenocarcinoma.

BackgroundSomatic mutations of the TP53 gene occur frequently in pancreatic ductal adenocarcinoma (PDA). Solute carrier family 45 member A4 (SLC45A4) is a H+‐dependent sugar cotransporter. The role of SLC45A4 in PDA, especially in TP53 mutant PDA, remains poorly understood.MethodsWe explored the TCGA datasets to identify oncogenes in TP53 mutant PDA. MTS [3‐(4,5‐dimethylthiazol‐2‐yl)‐5‐(3‐carboxymethoxyphenyl)‐2‐(4‐sulfophenyl)‐2H‐tetrazolium], colony formation and 5‐ethynyl‐2′‐deoxyuridine (Edu) assays were performed to investigate the function of SLC45A4 in vitro. Glucose consumption, lactate production and ATP production were detected to evaluate glucose utilization. Extracellular acidification rate and oxygen consumption rate assays were used to evaluate glycolysis and oxidative phosphorylation. The subcutaneous xenotransplantation models were conducted to explore the function of SLC45A4 in vivo. RNA‐sequencing and gene set enrichment analysis were employed to explore the biological alteration caused by SLC45A4 knockdown. Western blotting was performed to evaluate the activation of glycolysis, as well as the AMPK pathway and autophagy.ResultsSLC45A4 was overexpressed in PDA for which the expression was significantly higher in TP53 mutant PDA than that in wild‐type PDA tissues. Moreover, high level of SLC45A4 expression was tightly associated with poor clinical outcomes in PDA patients. Silencing SLC45A4 inhibited proliferation in TP53 mutant PDA cells. Knockdown of SLC45A4 reduced glucose uptake and ATP production, which led to activation of autophagy via AMPK/ULK1 pathway. Deleting SLC45A4 in TP53 mutant HPAF‐II cells inhibited the growth of xenografts in nude mice.ConclusionsThe present study found that SLC45A4 prevents autophagy via AMPK/ULK1 axis in TP53 mutant PDA, which may be a promising biomarker and therapeutic target in TP53 mutant PDA.

Docosahexaenoic acid inhibits the proliferation of Kras/TP53 double mutant pancreatic ductal adenocarcinoma cells through modulation of glutathione level and suppression of nucleotide synthesis.

The treatment of cancer cells obtained by blocking cellular metabolism has received a lot of attention recently. Previous studies have demonstrated that Kras mutation-mediated abnormal glucose metabolism would lead to an aberrant cell proliferation in human pancreatic ductal adenocarcinoma (PDAC) cells. Previous literature has suggested that consumption of fish oil is associated with lower risk of pancreatic cancer. In this study, we investigated the anti-cancer effects of docosahexaenoic acid (DHA) in human PDAC cells in vitro and in vivo. Omega-3 polyunsaturated fatty acids (PUFAs) such as DHA and eicosapentaenoic acid (EPA) significantly inhibited the proliferation of human PDAC cells. The actions of DHA were evaluated through an induction of cell cycle arrest at G1 phase and noticed a decreased expression of cyclin A, cyclin E and cyclin B proteins in HPAF-II cells. Moreover, it was found that co-treatment of DHA and gemcitabine (GEM) effectively induced oxidative stress and cell death in HPAF-II cells. Interestingly, DHA leads to an increased oxidative glutathione /reduced glutathione (GSSG/GSH) ratio and induced cell apoptosis in HPAF-II cells. The findings in the study showed that supplementation of GSH or N-Acetyl Cysteine (NAC) could reverse DHA-mediated cell death in HPAF-II cells. Additionally, DHA significantly increased cellular level of cysteine, cellular NADP/NADPH ratio and the expression of cystathionase (CTH) and SLCA11/xCT antiporter proteins in HPAF-II cells. The action of DHA was, in part, associated with the inactivation of STAT3 cascade in HPAF-II cells. Treatment with xCT inhibitors, such as erastin or sulfasalazine (SSZ), inhibited the cell survival ability in DHA-treated HPAF-II cells. DHA also inhibited nucleotide synthesis in HPAF-II cells. It was demonstrated in a mouse-xenograft model that consumption of fish oil significantly inhibited the growth of pancreatic adenocarcinoma and decreased cellular nucleotide level in tumor tissues. Furthermore, fish oil consumption induced an increment of GSSG/GSH ratio, an upregulation of xCT and CTH proteins in tumor tissues. In conclusion, DHA significantly inhibited survival of PDAC cells both in vitro and in vivo through its recently identified novel mode of action, including an increment in the ratio of GSSG/GSH and NADP/NADPH respectively, and promoting reduction in the levels of nucleotide synthesis.

Oncogenic roles of CEACAM6 in pancreatic ductal adenocarcinoma.

e16744 Background: Carcinoembryonic cell adhesion molecule 6 (CEACAM6) is a cell adhesion receptor of the Ig-superfamily overexpressed in human Pancreatic Ductal Adenocarcinoma (PDA), enriching to the classical activated stroma subtype. CEACAM6 has multifaceted roles in PDA and is a poor prognostic maker (Pandey et al. Sci Rep 2019). We report functional correlative studies across PDA cell lines with high vs KO vs low of CEACAM6 and a PDX model with a therapeutic Mab. Methods: RNA-Seq and microarray expression data of PDA cell lines were downloaded from GEO using R (4.3), normalized and log transformed for analysis: CEACAM6 high vs. low were assessed for differential gene expression changes. Correlation of CEACAM6 levels with genes of interest was studied and compared with the CEACAM6 KO proteomic profile of HPAF-II cells. CEACAM6 WT vs. KO cells were profiled for protein kinase (PK) activity (PAMChip) and gene expression changes by RNA-Seq. NSG-CD34+ mice bearing PDX were evaluated with a humanized anti-CEACAM6 Mab for anti-tumor activity. Results: Differential expression analyses between PDA cell lines with low vs KO vs high CEACAM6 resulted in identifying similar markers changing in quantitative proteomics. KRT20, SYTL1, SKIL, CES1P1, MAN1A1 were down-regulated and HMOX1, CPNE2, ABCD1 were up-regulated in CEACAM6 low or KO cell lines. Specific PKs are upregulated in CEACAM6 KO enriching to the TK family (EPH A1, 3, 4, 8 and HCK), AGC family (e.g. AKT, PKA) and cellular apoptosis (e.g. BAD). RNA-Seq of CEACAM6 WT vs KO cells reconfirmed the up-regulation of MMP1, IL2RG, ATP6V0D2 and low expression of KRT20, AGK and MAN1A1 in CEACAM6 KO cells. Pharmacologic inhibition with a humanized anti-CEACAM6 scFv-Fc (IgG4) in PDA PDX of NSG CD34+ mice demonstrated ~55% tumor growth inhibition (TGI) with enhanced survival of > 14 days vs. control. Conclusions: CEACAM6 is expressed exclusively in primates and humans and plays multifaceted oncogenic roles in PDA pathogenesis. When CEACAM6 is disrupted, ECM proteins are altered reshaping the stroma, activating specific PKs and priming apoptosis. The therapeutic anti-CEACAM6 Mab possesses anti-tumor activity with associated cellular apoptosis and increased mouse survival.

Biophysical changes caused by altered MUC13 expression in pancreatic cancer cells

BackgroundPancreatic cancer is one of the most lethal cancers in the United States. This is partly due to the difficulty in early detection of this disease as well as poor therapeutic responses to currently available regimens. Our previous reports suggest that mucin 13 (MUC13, a transmembrane mucin common to gastrointestinal cells) is aberrantly expressed in this disease state, and has been implicated with a worsened prognosis and an enhanced metastatic potential in PanCa. However, virtually no information currently exists to describe the biophysical ramifications of this protein. MethodsTo demonstrate the biophysical effect of MUC13 in PanCa, we generated overexpressing and knockdown model cell lines for PanCa and subsequently subjected them to various biophysical experiments using atomic force microscopy (AFM) and cellular aggregation studies. ResultsAFM-based nanoindentation data showed significant biophysical effects with MUC13 modulation in PanCa cells. The overexpression of MUC13 in Panc-1 cells led to an expected decrease in modulus, and a corresponding decrease in adhesion. With MUC13 knockdown, HPAF-II cells exhibited an increased modulus and adhesion. These results were confirmed with altered cell-cell adhesion as seen with aggregation assays. ConclusionsMUC13 led to significant biophysical changes in PanCa cells and which exhibited characteristic phenotypic changes in cells demonstrated in previous work from our lab. This work gives insight into the use of biophysical measurements that could be used to help diagnose or monitor cancers as well as determine the effects of genetic alterations at a mechanical level.

Abstract B60: Optimization of biologic scheduling of gemcitabine and abraxane improves treatment response compared to the standard concurrent regimen in preclinical models of pancreatic cancer

Abstract Introduction: Gemcitabine (gem) and Abraxane (albumin-bound paclitaxel, abx) combination chemotherapy delivered on the same day is now one of the preferred chemotherapy regimens for metastatic and locally advanced pancreatic ductal adenocarcinoma (PDAC) based on results of the phase III MPACT clinical trial that showed improved overall survival of gem+abx compared to gem alone in the metastatic/advanced setting. Our previous published works revealed that caveolin-1 (Cav-1), the principal structural component of caveolae and mediator of endocytosis, is highly expressed in PDAC cells and associated with enhanced tumor progression and resistance to gem in PDAC preclinical models. We also found that loss of Cav-1 through genetic knockdown inhibited both PDAC cell uptake of albumin and response to albumin-based chemotherapies, i.e., abx. In addition, gem treatment resulted in a time-dependent increase in Cav-1 protein expression. Taken together, we hypothesized pretreatment with gem would increase the efficacy of the gem/abx combination via increased Cav-1 dependent albumin-bound chemotherapy uptake. Results: ASPC1 and HPAFII PDAC cell lines were exposed to gem (25-100nM) for 24-48 hours followed by a 1-hour albumin pulse and displayed a time-dependent increase in intracellular albumin via Western blotting. We next tested PDAC cell proliferation and cell survival via alamarBlue and colony formation assays with various different gem/abx scheduling combinations. HPAFII and ASPC1 cells were treated for 24 hours with the following schedules: (1) vehicle, (2) gem alone, (3) abx alone, (4) gem+abx on same day (d1gem+abx), (5) gem on day 1 and abx day 2 (d1gem_d2abx), or (6) gem on day 1, no drug on day 2 and abx on day 3 (d1gem_d3abx). Both alternative schedules of d1gem_d2abx and d1gem_d3abx had greater inhibition of proliferation and colony formation compared to the current standard of care d1gem+abx, and of all the combinations, d1gem_d3abx was the most efficacious (p<0.01). Genetic knockdown of Cav-1 through short-hairpin loop RNA (shRNA) in Mia-Paca2 cells resulted in reversal of the observed altered scheduling effect on cell proliferation and survival. In vivo, we compared tumor growth rates with altering gem-abx scheduling following subcutaneous injection into athymic nude mice of ASPC1 or HPAFII cells. Similar to our in vitro studies, mice were treated with either the control-vehicle or three cycles delivered over 9 days of the following gem-abx combinations: 1) d1gem+abx, 2) d1gem_d2abx, or 3) d1gem_d3abx. The d1gem_d3abx scheduling had the most significant delay in tumor growth and tumor doubling time compared to the other gem-abx schedules (p<0.001). Conclusion: We found 24- to 48-hour gem treatment increased albumin uptake, leading to maximal treatment efficacy with an optimized schedule of gem delivered on day 1 and abx on day 3 compared to the standard gem+abx administered on the same day. These findings support further testing of an altered and biologically optimized scheduling of gemcitabine and Abraxane. Citation Format: Adam R. Wolfe, Ryan Robb, Ahmad Hegazi, Duan-Liang Shyu, Laith Abushahin, Terence M. Williams. Optimization of biologic scheduling of gemcitabine and abraxane improves treatment response compared to the standard concurrent regimen in preclinical models of pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr B60.