MIA PaCa-2 Cells Research Articles

Abstract 3324: Discovery of a novel SOS1 inhibitor, AIG01012, targeting pan-KRAS mutant cancers

Abstract Targeting the SOS1-KRAS interaction represents a pivotal strategy in mitigating aberrant KRAS signaling, which is implicated in numerous malignancies. At AIGEN Sciences, Inc., we have harnessed an advanced human-in-the-loop (HITL) AI-based drug discovery platform (AIGEN ChemTailor). This innovative platform allows online learning through expert feedback, optimizing our drug development endeavors. We designed a potent SOS1 inhibitor, AIG01012 using AIGEN ChemTailor in combination with fragment-based drug discovery (FBDD) and molecular modeling techniques. We conceived numerous compounds and shortlisted the leading candidates for extensive testing after meticulous computer simulations. AIG01012 manifested substantial inhibitory effects against several KRAS mutant interactions with SOS1, specifically SOS1-KRAS WT, SOS1-KRAS G12C, SOS1-KRAS G12D, SOS1-KRAS G12V, and SOS1-KRAS G13D. However, its inhibitory capacity did not extend to the SOS2-KRAS G12C interaction. AIG01012 demonstrated remarkable inhibitory effects in 3D cell proliferation assays across various cell lines, including H358, MIA-PaCa2, SW837, AsPC-1, A427, SW620, Capan-2, A549, DLD-1, MKN-1, and H1666. Moreover, AIG01012 showed synergistic antiproliferative effects when combined with approved drugs such as sotorasib (for lung cancer with KRAS mutations), trametinib (a MEK inhibitor), and Osimertinib (targets specific EGFR mutations) in either H358 or PC-9 cell lines. Mouse studies further confirmed its favorable pharmacological properties, and its efficacy was evaluated in subsequent mouse tumor model. In summary, utilizing our human-in-the-loop (HITL) AI platform, AIGEN ChemTailor, we have efficiently derived AIG01012 as a potent SOS1 inhibitor that targets a wide range of KRAS interactions. With its notable in vitro and in vivo outcomes, AIG01012 is set for further exploration and prospective clinical trials as a significant contender in KRAS-targeted cancer treatments. Citation Format: Jihye Kim, Sejeong Park, Sunkyu Kim, Sanghoon Lee, Kiwoong Yoo, Ho-Jeong Lee, Jaewoo Kang, Kwang-Ok Lee. Discovery of a novel SOS1 inhibitor, AIG01012, targeting pan-KRAS mutant cancers [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 3324.

Abstract 5597: Clinical significance of RNA polymerase I inhibitor in pancreatic cancer therapy

Abstract Pancreatic cancer (PanCa) is the third leading cause of cancer-related deaths in the United States with limited therapeutic options available. Gemcitabine (GEM), a deoxycytidine nucleoside analog is currently considered the most effective therapy for PanCa. However, it shows only a marginal survival benefit of six months. Aberrant ribosome biogenesis occurs in most tumor types. We observed that PanCa cells are addicted to ribosome biogenesis (RiBi), which supports their highly aggressive metastatic phenotypes. Thus, strategically targeting RiBi process could be one of the ideal strategies for the prevention and treatment of PanCa. In this study, we elucidated the molecular mechanisms of POLR1A (RPA194) overexpression and how its targeting along with p53 status impacts RNA polymerase I inhibitor therapy against PanCa. The expression level of RPA194 was significantly elevated in pancreatic tumor tissues when compared with adjacent normal pancreatic tissues. BMH-21 is a potent pharmacological inhibitor of RNA Pol I, which is known to degrade RPA194 protein. Our results demonstrated that BMH-21 can selectively induce apoptosis in various PanCa cells but not in HPNE cells. We also found that the cytotoxic effect of BMH-21 was dependent on the expression pattern of RPA-194 and p53 status. We further examined the therapeutic efficacy of BMH-21 in orthotopic xenograft mouse models by using two different PanCa cells, AsPC1 which contains non-functional p53 and MIA PaCa-2 which contains functional mutant p53. We observed that BMH-21 significantly inhibited the growth of tumors derived from both cancer cell lines. Interestingly, BMH-21-mediated inhibition of tumor growth was more significant in tumors derived from MIA PaCa-2 cells compared to AsPC1 cells. Further examination revealed that the inhibition of tumor growth was correlated with RPA194 degradation followed by inhibition of cell proliferation. Overall, our results strongly suggest that BMH-21 is a promising non-toxic agent for the treatment of advanced PanCa and its therapeutic potential depends on RPA194 expression and p53 status in PanCa cells. Citation Format: Mudassier Ahmad. Clinical significance of RNA polymerase I inhibitor in pancreatic cancer therapy [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 5597.

Abstract 3350: The pan-quadruplex drug QN-302 targets up-regulated genes in pancreatic cancer and in other cancer types and correlate with poor patient prognosis

Abstract We have previously disclosed (Ahmed et al, ACS Med Chem Lett, 2020) a novel small molecule G-quadruplex binding compound, QN-302, that is highly potent in pancreatic ductal adenocarcinoma (PDAC) cells and in several in vivo models for this disease. QN-302 was invented at University College London UK and has been subsequently developed by Qualigen Therapeutics Inc. It was cleared by the FDA in August 2023 for clinical evaluation and is currently in a Phase 1 clinical trial at select oncology centers in the USA. Genes that are significantly down-regulated by QN-302 are mostly up-regulated genes in human PDAC. We report here that some of these genes are also up regulated in other cancer types, whose expression frequently correlates with poor patient prognosis. We have used human cancer data from https://www.proteinatlas.org which contains pathology information based on mRNA and protein expression data from 17 different forms of human cancer, together with millions of in-house generated immunohistochemically stained tissue sections, images and Kaplan-Meier plots showing the correlation between mRNA expression of each human protein gene and cancer patient survival. We have revisited the RNA-seq data for QN-302 in PDAC MIA-PACA2 cells exposed to QN-302 for 24 hrs. (GSE151741 at https://www.ncbi.nlm.nih.gov/geo/) in detail and now identify a small group of eleven down-regulated genes, all with >3-fold expression changes. Interestingly all these genes and their gene products have been previously identified as playing a role in human PDAC (they also have varying roles in other cancer types). Some have been validated as anticancer targets. 10/11 of these genes (https://www.proteinatlas.org/) have been previously reported as being over-expressed in significant fractions of large (>150) groups of human cancer patients from The Cancer Genome Atlas (TCGA) project. Members of the PDAC susceptible gene panel are mostly disfavored in prostate, lung and breast cancer. However, the patient data does not discriminate between cancer sub-types nor does it show resistant data. They are especially favored in colorectal, liver and renal cancers, suggesting that QN-302 may have anticancer effects in these cancers as well as in PDAC. We also do not exclude the strong possibility that each cancer type also has its own group of G-quadruplex containing genes that are sensitive to QN-302. Citation Format: Stephen Neidle, Ahmed A. Ahmed, Tariq Arshad. The pan-quadruplex drug QN-302 targets up-regulated genes in pancreatic cancer and in other cancer types and correlate with poor patient prognosis [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 3350.

Abstract 576: The pan-quadruplex drug QN-302 selectively down-regulates key pathway targets in pancreatic cancer cells that are up-regulated in human pancreatic cancer

Abstract We have previously disclosed (Ahmed et al, ACS Med Chem Lett, 2020) a novel small molecule G-quadruplex binding compound, QN-302, that is highly potent in pancreatic ductal adenocarcinoma (PDAC) cells and in several in vivo models for this disease. QN-302 was invented at University College London UK and has been subsequently developed by Qualigen Therapeutics Inc. It was cleared by the FDA in August 2023 for Phase 1a clinical trials in USA and is currently under clinical evaluation. RNA-seq whole-genome transcriptome analysis revealed that QN-302 selectively targets G-quadruplexes in cancer-related genes, notably by forming stable G-quadruplex complexes with appropriate promoter sequences. This results in the transcriptional down regulation of affected genes, which map to for example, the hedgehog, axon guidance, WNT/β-catenin and P38 signal transduction pathways. In many instances individual expression changes are modest, though statistically significant: cumulatively, they affect whole pathways. We have revisited the RNA-seq data for QN-302 in PDAC MIA-PACA2 cells (GSE151741 at https://www.ncbi.nlm.nih.gov/geo/) in detail and now identify a small group of eleven down-regulated genes, all with >3-fold expression changes. Interestingly all these genes and their genes products have been previously identified as playing a role in human PDAC (they also have varying roles in other cancer types). Some have been validated as anticancer targets. 10/11 of these genes (https://www.proteinatlas.org/) have been previously reported as being over-expressed in significant fractions of large (>150) groups of human cancer patients from The Cancer Genome Atlas (TCGA) project. Cellular transcriptome data on these eleven genes is presented here, which together with earlier reports on them, supports the designation of QN-302 as a pan-G-quadruplex agent targeting a group of major genes involved in PDAC maintenance and metastasis. Data from a xenograft model for pancreatic cancer is also available for four of these genes, which concurs with the cellular data. We suggest that the identification of these 11 genes may also provide a basis for biomarker selection and possible patient stratification based on transcriptome data. Citation Format: Stephen Neidle, Ahmed A. Ahmed, Tariq Arshad. The pan-quadruplex drug QN-302 selectively down-regulates key pathway targets in pancreatic cancer cells that are up-regulated in human pancreatic cancer [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 576.

Abstract 4460: Investigating a non-canonical role for SHP2 in pancreatic ductal adenocarcinoma metabolism and response to dietary modifications

Abstract Pancreatic ductal adenocarcinoma (PDAC) is predicted to be the second leading cause of cancer death in the US by 2025, with rising incidence. Mutant KRAS in >90% of PDAC cases promotes activation of the MAPK pathway, yet targeting the MAPK pathway clinically has failed to improve patient outcomes. SHP2 canonically promotes KRAS activation and is essential for PDAC development in mouse models. Because targeting MAPK is insufficient, yet SHP2 loss blocks PDAC development, we hypothesized SHP2 has both MAPK dependent and independent functions. Initial studies revealed that SHP2 inhibition with SHP099 in murine KPC [K8484: KRASG12D/+, p53R172H/+, Pdx1Cre/+] cells required concentrations exceeding 50 μM to elicit a minimal ERK inhibition. This led us to predict that there may be a tumor suppressive mechanism of SHP2 inhibition that is KRAS/MAPK independent. We utilized available RNAseq data (NCBI GEO: PRJNA558508) of PDAC MiaPaCa2 cells treated with the MEK inhibitor, Trametinib, or SHP099 to compare the direct effects of inhibition on transcriptional outcomes. We identified inositol phosphate signaling as a candidate target, whose downstream consequence is Ca2+ flux. We measured IL-1β induced Ca2+ flux in a panel of human PDAC cells exposed to MEK or SHP2 inhibition. Trametinib treated cells showed no effect on Ca2+ flux, however, SHP099 led to a drastic depletion of free Ca2+ and response to stimulus. We then validated the Ca2+ response to IL-1β stimulus in Crispr-Cas9 SHP2-knockout K8484 cells. While we did not observe a difference in basal free calcium, we still found a reduction in response to IL-1β stimulus. Because Ca2+ is an important co-factor for mitochondrial metabolism, we then interrogated metabolic effects. We tested mitochondrial function using a Seahorse Mito-Stress test and found that while MEK inhibition failed to affect mitochondrial metabolism, SHP2 inhibition ablated it. A Glycolysis-Stress Test revealed that SHP2 inhibition led to glucose consumption primarily through anaerobic respiration. TMT-labeled phospho-proteomic analysis comparing SHP2KO and MEK inhibited K8484s revealed SHP2 dependent deficiencies in mitochondrial proteins, among others, involved in mitochondrial fission and lipid metabolism. Western diets have been shown to promote tumor progression in GEM models of PDAC, so we used KRASG12D/+, SHP2fl/fl or wt./wt, Ptf1aCre/+ (SKC and KC) mice to demonstrate that while diet-induced obesity affects KC tumor burden, the lack of SHP2 in SKCs prevents the diet associated discrepancy in tumor progression. Collectively, these data led us to conclude that while SHP2 has been studied as a contributor to KRAS signaling in PDAC, the outcomes of its role specifically on mitochondrial metabolism have yet to be appreciated or thoroughly investigated, opening the path for a new approach to its contribution to tumor progression. Citation Format: R. McKinnon Walsh, Jarrid L. Jack, Austin E. Eades, Bailey A. Bye, Mariana T. Ruckert, Joseph Ambrose, Michael N. VanSaun. Investigating a non-canonical role for SHP2 in pancreatic ductal adenocarcinoma metabolism and response to dietary modifications [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 4460.

Abstract 2431: Identification of highly expressed exosomal RNAs derived from pancreatic cancer cell lines and exploration of their potential as biomarkers

Abstract Background: Not all exosomes in the blood of cancer patients originate from cancer cells. This study evaluated the relationships between mRNAs and miRNAs in pancreatic cancer (PC) cell lines and those in exosomes secreted into the supernatant. We aimed to identify candidates for PC biomarkers from cancer-specific exosomal mRNAs and miRNAs. Materials and Methods: Three PC cell lines were utilized. Exosomes were isolated from the supernatant, and cellular and exosomal mRNAs and miRNAs were extracted. Subsequently, RNA sequencing (RNA-seq) was performed, and the data were analyzed using R software. Results: In the MIAPaCa-2 cell line, the expression of cellular mRNAs and corresponding exosomal mRNAs showed a strong correlation. In the other two cell lines, a moderate correlation was observed. Across all three cell lines, cellular miRNAs and corresponding exosomal miRNAs exhibited moderate correlation. We focused on RNAs that were lowly expressed in cells but highly expressed in exosomes and conducted differential expression analysis using R. Compared with healthy volunteers in the GEO database, some RNAs showed high expression in the supernatant and low expression in the plasma of healthy volunteers. Conclusion: We identified three mRNAs and three miRNAs that may serve as promising biomarker candidates for PC. Citation Format: Yuhan Rong, Naoki Okubo, Noritoshi Kobayashi, Eriko Katsuta, Yasushi Ichikawa. Identification of highly expressed exosomal RNAs derived from pancreatic cancer cell lines and exploration of their potential as biomarkers [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 2431.

Abstract 3164: The in vivo Hollow Fiber model is a valuable tool in drug development of selective KRas inhibitors

Abstract The proto-oncogene KRas is a well-described small GTPase that functions as a molecular switch for major physiological signaling pathways involved in cell proliferation, differentiation and survival. It has been shown that activating mutations in KRas are among the most common oncogenic drivers of tumorigenesis. Missense mutations of KRas result in constitutive activation due to impaired hydrolysis of GTP which enhances tumor-promoting downstream signaling pathways. Most KRas mutations are located in exon 2 or 3 including the most frequently altered glycine 12, which is present in most pancreatic cancers as well as in colorectal cancers and lung adenocarcinomas. A panel of cancer cell lines harboring different KRas mutations such as G12C, G12V or G12D was selected to test KRas inhibitors in several cellular assays: phosphorylation assays, 2D and 3D proliferation assays. Applying the cellular pERK AlphaLISA assay showed high selectivity of several inhibitors for specific KRas mutants, while RAF and MEK inhibitors did not show significant selectivity in the tested cancer cell lines. The KRas inhibitors were then examined in a cellular 2D and a 3D spheroid proliferation assay to determine the inhibitory effect on cell growth. These cellular assays revealed a high selectivity for a specific KRas mutant, which was even more pronounced in the 3D format than in the 2D setup. The transferability of the cellular data obtained to in vivo was tested in the Hollow Fiber mouse model. The Hollow Fiber model allows the simultaneous study of multiple cell lines implanted in separated drug-(but not cell-) permeable fibers in a single mouse with a study duration of only 16 days. AMG510 (Sotorasib), a drug approved for tumors with a G12C Kras mutation, and MRTX1133, which is currently in clinical phase and shows activity in tumors with a G12D Kras mutation, were screened for their inhibitory effect on the pancreatic tumor cells MiaPaCa-2 (G12C Kras mutation), AsPC-1 (G12D Kras mutation) and BxPC-3 (wt Kras) in the in vivo Hollow Fiber model in female NMRI nude mice. While the growth of BxPC-3 tumor cells was not affected by either inhibitor, the growth of AsPC-1 tumor cells in particular was selectively and significantly inhibited by MRTX1133. In summary, the in vivo Hollow Fiber model is a fast and cost-effective model that can play an prominent role in drug development as a link between in vitro and in vivo xenograft studies by providing rapid and transferable evidence for in vivo efficacy. Citation Format: Philipp Metzger, Claus-Werner Franzke, Ezgi Dikici, Gregor Sommerkamp, Franziska Fimm-Todt, Jan E. Ehlert, Cynthia Obodozie, Holger Weber. The in vivo Hollow Fiber model is a valuable tool in drug development of selective KRas inhibitors [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 3164.

Efficient Assessment of Tumor Vascular Shutdown by Photodynamic Therapy on Orthotopic Pancreatic Cancer Using High-Speed Wide-Field Waterproof Galvanometer Scanner Photoacoustic Microscopy.

To identify the vascular alteration by photodynamic therapy (PDT), the utilization of high-resolution, high-speed, and wide-field photoacoustic microscopy (PAM) has gained enormous interest. The rapid changes in vasculature during PDT treatment and monitoring of tumor tissue activation in the orthotopic pancreatic cancer model have received limited attention in previous studies. Here, a fully two-axes waterproof galvanometer scanner-based photoacoustic microscopy (WGS-PAM) system was developed for in vivo monitoring of dynamic variations in micro blood vessels due to PDT in an orthotopic pancreatic cancer mouse model. The photosensitizer (PS), Chlorin e6 (Ce6), was utilized to activate antitumor reactions in response to the irradiation of a 660 nm light source. Microvasculatures of angiogenesis tissue were visualized on a 40 mm2 area using the WGS-PAM system at 30 min intervals for 3 h after the PDT treatment. The decline in vascular intensity was observed at 24.5% along with a 32.4% reduction of the vascular density at 3 h post-PDT by the analysis of PAM images. The anti-vascularization effect was also identified with fluorescent imaging. Moreover, Ce6-PDT increased apoptotic and necrotic markers while decreasing vascular endothelial growth factor (VEGF) expression in MIA PaCa-2 and BxPC-3 pancreatic cancer cell lines. The approach of the WGS-PAM system shows the potential to investigate PDT effects on the mechanism of angiographic dynamics with high-resolution wide-field imaging modalities.

Silver nanoparticles green-formulated by a medicinal plant for the treatment of pancreatic, colorectal, and gastric cancers

Pancreatic, colorectal, and gastric cancers are common cancers with severe clinical signs. Finding a new anticancer supplement or drug inside of the chemotherapeutic drug is valuable. We synthesized iron nanoparticles containing pomegranate fruit aqueous extract for investigating anti-pancreatic cancer, anti-colorectal cancer, and anti-gastric cancer, cytotoxicity, and antioxidant effects. The AgNPs synthesized using green formulation underwent characterization through FT-IR, UV–Vis, FE-SEM, TEM, EDX, and XRD techniques. The UV–Vis spectroscopy analysis revealed that the nanoparticles displayed peak absorption at around 442 nm. The peaks at 77.105, 64.205, 44.180, and 37.835 corresponding to silver nanoparticles (311), (220), (200), and (111) diffraction planes, indicate the AgNPs formation. The signals at energy of 2.64 and 3.02 keV are assigned for Ag Lα and Ag Lβ. The signals 0.27 (for C Lα) and 0.52 (O Lα) prove the secondary metabolites linkage of extract to the synthetic silver nanoparticles surface. In vitro experiments, after 3–4 passages, the cancer cells (colorectal carcinoma (Ramos.2G6.4C10 and HT-29), gastric cancer (KATO III and MKN45), and pancreatic cancer (MIA PaCa-2 and PANC-1)) and normal cell (HUVEC) were prepared in number and morphology terms. After separating the cells from the flask surface using trypsin-EDTA, the viability and count of the cells were evaluated. Subsequently, a total of 3 × 103 cells were cultured, with the option of including or excluding nanoparticles. IC50 of silver nanoparticles was 183, 209, 203, 218, 228, and 157 on Ramos.2G6.4C10, HT-29, KATO III, MKN45, MIA PaCa-2, and PANC-1 cancer cells. In this research, the maximum antioxidant effectiveness against DPPH was documented to be around 100 % when tested 1000 μg/ml.

Enhanced Anti-tumor Effect of Flavopiridol in Combination With Gemcitabine in Pancreatic Cancer.

The efficacy of current chemotherapies for pancreatic ductal adenocarcinoma (PDAC) is still unsatisfactory. Flavopiridol inhibits multiple cyclin-dependent kinases, causing cell cycle arrest and inducing cancer cell apoptosis. This study aimed to evaluate the anti-tumor effect of flavopiridol and gemcitabine in PDAC in vitro and in vivo. PANC-1 and MIA PaCa-2 cell lines were treated with gemcitabine and flavopiridol alone, in combination, and sequentially, and cell proliferation, apoptosis, and the cell cycle were evaluated. Proteins related to cell cycle progression (cyclin A, CDK2, E2F-1, and p53) were quantified using western blotting. A xenograft mouse model was generated, and the effects of gemcitabine and flavopiridol, administered alone or in combination, were evaluated by measuring tumor volume and apoptosis degree using the TUNEL assay. Sequential administration of gemcitabine and flavopiridol suppressed PDAC cell proliferation and induced apoptosis. Flavopiridol treatment led to an increase in the number of cells in the S and a decrease in those in the G0/G1 phases. Gemcitabine increased and decreased the number of S- and G2/M-phase cells, respectively. Furthermore, flavopiridol treatment decreased cyclin A and CDK2 expression and increased E2F-1 expression. In a xenograft mouse model, the combined administration of gemcitabine and flavopiridol demonstrated the most significant reduction in tumor volume and induction of apoptosis. Flavopiridol potentiates the anti-tumor activity of gemcitabine by inducing cell cycle arrest and apoptosis. Its synergistic inhibition of PDAC cell proliferation, when combined with gemcitabine, positions flavopiridol as a promising candidate for cancer treatment.

Identification of myoferlin as a mitochondria-associated membranes component required for calcium signaling in PDAC cell lines

BackgroundPancreatic ductal adenocarcinoma is an aggressive cancer type with one of the lowest survival rates due to late diagnosis and the absence of effective treatments. A better understanding of PDAC biology will help researchers to discover the Achilles’ heel of cancer cells. In that regard, our research team investigated the function of an emerging oncoprotein known as myoferlin. Myoferlin is overexpressed in PDAC and its silencing/targeting has been shown to affect cancer cell proliferation, migration, mitochondrial dynamics and metabolism. Nevertheless, our comprehension of myoferlin functions in cells remains limited. In this study, we aimed to understand the molecular mechanism linking myoferlin silencing to mitochondrial dynamics.MethodsExperiments were performed on two pancreas cancer cell lines, Panc-1 and MiaPaCa-2. Myoferlin localization on mitochondria was evaluated by immunofluorescence, proximity ligation assay, and cell fractionation. The presence of myoferlin in mitochondria-associated membranes was assessed by cell fractionation and its function in mitochondrial calcium transfer was evaluated using calcium flow experiments, proximity ligation assays, co-immunoprecipitation, and timelapse fluorescence microscopy in living cells.ResultsMyoferlin localization on mitochondria was investigated. Our results suggest that myoferlin is unlikely to be located on mitochondria. Instead, we identified myoferlin as a new component of mitochondria-associated membranes. Its silencing significantly reduces the mitochondrial calcium level upon stimulation, probably through myoferlin interaction with the inositol 1,4,5-triphosphate receptors 3.ConclusionsFor the first time, myoferlin was specifically demonstrated to be located in mitochondria-associated membranes where it participates to calcium flow. We hypothesized that this function explains our previous results on mitochondrial dynamics. This study improves our comprehension of myoferlin localization and function in cancer biology.

PTTG1 induces pancreatic cancer cell proliferation and promotes aerobic glycolysis by regulating c-myc.

This study aimed to clarify the role of pituitary tumor-transforming gene 1 (PTTG1) in proliferation, migration, invasion, and aerobic glycolysis of pancreatic cancer cells, and evaluate the potential of PTTG1 as a therapeutic target. PTTG1 expression in pancreatic cancers was analyzed using the GEPIA databank. In the Panc1 cell with the PTTG1 knockdown or Mia-PaCa2 cells with PTTG1 overexpression, the cell proliferation was evaluated using cell viability curves and colony formation, and wound heal assay and transwell assay were performed to evaluate the migration and invasion, respectively. Furthermore, a western blot was performed to evaluate the expressions of PTTG1, proliferating cell nuclear antigen, E-cadherin, N-cadherin, and c-myc. Meanwhile, the glucose uptake, extracellular acidification rates (ECAR), and oxygen consumption rates (OCR) were analyzed. Our results showed that PTTG1 expression is upregulated in pancreatic cancer, which promoted cell proliferation. Low PTTG1 contributed to higher disease-free survival and overall survival. In Panc1 cell, PTTG1 knockdown resulted in reduced cell viability and colony formation. The migration and invasion abilities of the cells were also reduced in Panc1 with PTTG1 knockdown. Correspondingly, PTTG1 knockdown decreased c-myc expression, glucose uptake, ECAR, and OCR in Panc1 cells. In Mia-PaCa2 cells, PTTG1 overexpression promoted cell proliferation, aerobic glycolysis, and translocation of β-catenin to the nucleus by regulating c-myc. In conclusion, PTTG1 induces proliferation, migration, and invasion, and promotes aerobic glycolysis in pancreatic cancer cells via regulating c-myc, demonstrating the potential of PTTG1 as a therapeutic target.

Cannabigerol Induces Autophagic Cell Death by Inhibiting EGFR-RAS Pathways in Human Pancreatic Ductal Adenocarcinoma Cell Lines.

Pancreatic ductal adenocarcinoma (PDAC) is the most frequent infiltrating type of pancreatic cancer. The poor prognosis associated with this cancer is due to the absence of specific biomarkers, aggressiveness, and treatment resistance. PDAC is a deadly malignancy bearing distinct genetic alterations, the most common being those that result in cancer-causing versions of the KRAS gene. Cannabigerol (CBG) is a non-psychomimetic cannabinoid with anti-inflammatory properties. Regarding the anticancer effect of CBG, up to now, there is only limited evidence in human cancers. To fill this gap, we investigated the effects of CBG on the PDAC cell lines, PANC-1 and MIAPaCa-2. The effect of CBG activity on cell viability, cell death, and EGFR-RAS-associated signaling was investigated. Moreover, the potential synergistic effect of CBG in combination with gemcitabine (GEM) and paclitaxel (PTX) was investigated. MTT was applied to investigate the effect of CBG on PDAC cell line viabilities. Annexin-V and Acridine orange staining, followed by cytofluorimetric analysis and Western blotting, were used to evaluate CBG's effect on cell death. The modulation of EGFR-RAS-associated pathways was determined by Western blot analysis and a Milliplex multiplex assay. Moreover, by employing the MTT data and SynergyFinder Plus software analysis, the effect of the combination of CBG and chemotherapeutic drugs was determined.

PW06 suppresses cancer cell metastasis in human pancreatic carcinoma MIA PaCa-2 cells via the inhibitions of p-Akt/mTOR/NF-κB and MMP2/MMP9 signaling pathways in vitro.

PW06 [(E)-3-(9-ethyl-9H-carbazol-3-yl)-1-(2,5-dimethoxyphenyl) prop-2-en-1-one], a kind of the carbazole derivative containing chalcone moiety, inducedcell apoptosisin human pancreatic carcinoma in vitro. There is no investigation to show that PW06 inhibits cancer cell metastasis in human pancreatic carcinoma in vitro. Herein, PW06 (0.1-0.8 μM) significantly exists in the antimetastatic activities of human pancreatic carcinoma MIA PaCa-2 cells in vitro. Wound healing assay shows PW06 at 0.2 μM suppressed cell mobility by 7.45 and 16.55% at 6 and 24 hours of treatments. PW06 at 0.1 and 0.2 μM reduced cell mobility by 14.72 and 21.8% for 48 hours of treatment. Transwell chamber assay indicated PW06 (0.1-0.2 μM) suppressed the cell migration (decreased 26.67-35.42%) and invasion (decreased 48.51-68.66%). Atomic force microscopy assay shows PW06 (0.2 μM) significantly changed the shape of cell morphology. The gelatin zymography assay indicates PW06 decreased MMP2's and MMP9's activitiesat 48 hours of treatment. Western blotting assay further confirms PW06 reduced levels of MMP2 and MMP9 and increased protein expressions of EGFR, SOS1, and Ras. PW06 also increased the p-JNK, p-ERK, and p-p38. PW06 increased the expression of PI3K, PTEN, Akt, GSK3α/β, and E-cadherin. Nevertheless, results also show PW06 decreased p-Akt, mTOR, NF-κB, p-GSK3β, β-catenin, Snail, N-cadherin, and vimentin in MIA PaCa-2 cells. The confocal laser microscopy examination shows PW06 increased E-cadherin but decreased vimentin in MIA PaCa-2 cells. Together, our findings strongly suggest that PW06 inhibited the p-Akt/mTOR/NF-κB/MMPs pathways, increased E-cadherin, and decreased N-cadherin/vimentin, suppressing the migration and invasion in MIA PaCa-2 cells in vitro.

Abstract C065: Base excision repair pathway regulates transcription-replication conflicts in pancreatic ductal adenocarcinoma

Abstract Oncogenic mutations (such as in KRAS) can dysregulate transcription and replication leading to transcription conflicts (TRCs). Unresolved TRCs can cause lethal DNA damage. Here, we sought to investigate the causal role of oncogenic mutations in regulating TRCs in pancreatic ductal adenocarcinoma (PDAC). Further, we characterize the adaptive pathways that mitigate TRCs for PDAC survival. Human PDAC demonstrated 30-120-fold higher levels of TRC genomic signature compared to breast, colon and lung cancer (p<0.001). Gene expression analysis demonstrated high levels of known TRC resolution factors in human tumors compared to normal tissues. TRCs as measured by RNAPII-PCNA proximity ligation assay were significantly enriched in human PDAC cells (Panc-1, BxPC3, MiaPaca2) compared to immortalized normal HPNE cells (p<0.001). Similarly transcriptomic complexes were enriched in nascent DNA immunoprecipitates from Panc1 cells but not HPNE cells. Ectopic expression of oncogenic KRAS(G12D) in human pancreatic ductal epithelial (HPNE) cells enhanced TRCs, and TRC-related DNA:RNA hybrids (R-loops). Inhibition of KRAS or downstream effectors abrogated TRCs in Panc1 and MiaPaca2 cells. An siRNA screen identified several factors in the base-excision repair (BER) pathway as regulators of TRCs. Sub-lethal exposure to hydrogen peroxide enhanced TRCs, whereas N-acetyl cysteine abrogated TRCs. These findings were validated by a pharmacologic approach using inhibitors of APE1 endonuclease in BER pathway (Methoxyamine and CRT). Mechanistic studies revealed that BER pathway inhibition severely altered RNA polymerase II dynamics at nascent DNA; causing RNAPII trapping and contributing to enhanced TRCs. The ensuing DNA damage activated Chk2-ATR pathway but not Chk1-ATM pathway. Co-treatment with ATR inhibitor (VX970, 10-80nM) and BER inhibitor (methoxyamine, 6-12mM) at clinically relevant doses, synergistically enhanced DNA damage and reduced clonogenic survival in PDAC cells. The study uncovers a novel role of BER pathway defects and oxidative DNA damage in promoting TRCs. Our studies provide mechanistic insights into the regulation of TRCs in PDAC which has implications for genome instability and therapy in PDAC. Citation Format: Fan Meng, Anup K. Singh, Tiane Li, Marc Attiyeh, Fatemeh Kohram, Terence Williams, Yilun Liu, Mustafa Raoof. Base excision repair pathway regulates transcription-replication conflicts in pancreatic ductal adenocarcinoma [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 C065.

Abstract B062: CRO67 has therapeutic potential against pancreatic tumor cells and cancer associated fibroblasts

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is highly resistant to therapy. Stromal cancer-associated fibroblasts (CAFs) play a key role in promoting tumor progression and chemoresistance, by creating a fibrotic microenvironment that impedes drug access and feeds PDAC cells nutrients and pro-tumor signals. CRO-67 (Patent PCT/AU2023/050505) is a novel drug developed with Noxopharm Ltd using a rational medicinal chemistry design to improve bioavailability of chromans which have potent anti-cancer activity. Using our patient-derived PDAC tumor in a dish model (explants; maintain multicellular architecture and fibrosis) we previously showed that CRO-67 has both anti-tumor and CAF reprogramming capacity in 4 patient explants [Cancer Res (2022) 82 (22_Supplement):C073]. Aims: 1) To expand evaluation of CRO-67 in additional patient-derived PDAC tumor explants given PDAC heterogeneity. 2) Assess the effect of CRO-67 on PDAC cell and CAF function. 3) Validate the therapeutic potential of CRO-67 on PDAC growth in vivo. Methods: 1) PDAC tumor samples collected from 7 patients undergoing pancreatic resection. Tumor explants (1–2mm diameter) were cultured on gelatin sponges, treated with CRO-67 (0–50μg/mL) every 3 days and fixed on day 12. Therapeutic response assessed by immunohistochemistry for cytokeratin (PDAC cells), α-smooth muscle actin (CAFs), bromodeoxyuridine (proliferation) and TUNEL (cell death). 2) PDAC cells (MiaPaCa-2) and patient-derived CAFs were treated with CRO-67 (1.5μM) for 48h before proliferation analysis (IncuCYTE S3) and for 24h before apoptosis (Annexin V/DAPI staining; flow cytometry) and cell cycle (DAPI staining; flow cytometry) analysis. 3) Subcutaneous PDAC (BxPC3 human cells) tumors in mice were treated with CRO-67 (2.5mg/kg Intraperitoneally, twice a day) for 21 days and tumor volume measured (calipers). Results: 1) CRO-67 treatment decreased tumor and CAF cell frequency in 6/6 (no quantifiable tumor in patient 7 explants) and 7/7 patient PDAC explants, respectively. It also decreased explant cell proliferation and increased cell death versus controls. 2) CRO-67 completely abolished proliferation of MiaPaCa-2 and reduced the average growth rate of CAFs by 81.3±8.8% (p=0.0025; n=5), increased apoptosis in MiaPaCa-2 by 455.7±21.4% (p=0.003; n=3) and in CAFs by 172.6±13.1% (p=0.0067; n=5) and increased the fraction of cells in G2/M cell cycle phase by 163.8±12.8% (p<0.0001; n=3) in MiaPaCa-2 and by 74.6±8.6% (p=0.0015; n=5) in CAFs versus controls. 3) CRO-67 reduced PDAC tumors in vivo by 56.7±6.6% (p=0.0013; n=9 mice/group) versus controls. Conclusions: CRO-67: 1) reduced PDAC cells and CAFs in human PDAC explants via reduced proliferation and increased death; 2) reduced proliferation of PDAC cells and CAFs in vitro, increased apoptosis and disrupted cell cycle progression through G2/M phase; 3) reduced PDAC tumor growth in vivo. Implication: We predict CRO-67 is a potential ‘dual cell’ therapy with direct anti-tumor effects and CAF reprogramming capacity, warranting further investigation in vivo. Citation Format: Keilah Garcia Netto, Shannon Chiang, John Kokkinos, Koroush S. Haghighi, Aparna Raina, Omali Pitiyarachchi, Janet Youkhana, Quach Truong, Daniel Wenholz, Xiang Li, Olivier Laczka, Naresh Kumar, John Wilkinson, David Goldstein, George Sharbeen, Phoebe A. Phillips. CRO67 has therapeutic potential against pancreatic tumor cells and cancer associated fibroblasts [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 B062.

Cancer-associated fibroblasts promote stemness maintenance and gemcitabine resistance via HIF-1α/miR-21 axis under hypoxic conditions in pancreatic cancer.

Gemcitabine (GEM) resistance affects chemotherapy efficacy of pancreatic cancer (PC). Cancer-associated fibroblasts (CAFs) possess the ability of regulating chemoresistance. This study probed the mechanism of hypoxia-treated CAFs regulating cell stemness and GEM resistance in PC. Miapaca-2/SW1990 were co-cultured with PC-derived CAFs under normoxic/hypoxic conditions. Cell viability/self-renewal ability was determined by MTT/sphere formation assays, respectively. Protein levels of CD44, CD133, Oct4, and Sox2 were determined by western blot. GEM tumoricidal assay was performed. PC cell GEM resistance was evaluated by MTT assay. CAFs were cultured at normoxia/hypoxia. HIF-1α and miR-21 expression levels were assessed by RT-qPCR and western blot, with their binding sites and binding relationship predicted and verified. CAF-extracellular vesicles (EVs) were incubated with Miapaca-2 cells. The RAS/AKT/ERK pathway activation was detected by western blot. PC xenograft models were established and treated with hypoxic CAF-EVs and GEM. CAFs and PC cell co-culture increased cell stemness maintenance, GEM resistance, cell viability, stem cell sphere number, and protein levels of CD44, CD133, Oct4, and Sox2, and weakened GEM tumoricidal ability to PC cells, with the effects further enhanced by hypoxia. Hypoxia induced HIF-1α and miR-21 overexpression in CAFs. Hypoxia promoted CAFs to secrete high-level miR-21 EVs via the HIF-1α/miR-21 axis, and activated the miR-21/RAS/AKT/ERK pathway. CAF-EVs promoted GEM resistance in PC via the miR-21/RAS/ATK/ERK pathway in vivo. Hypoxia promoted CAFs to secrete high-level miR-21 EVs through the HIF-1α/miR-21 axis, and activated the miR-21/RAS/AKT/ERK pathway via EVs to trigger stemness maintenance and GEM resistance in PC.

Ninjurin 2, a Cell Adhesion Molecule and a Target of p53, Modulates Wild-Type p53 in Growth Suppression and Mutant p53 in Growth Promotion.

The nerve injury-induced protein 1 (NINJ1) and NINJ2 constitute a family of homophilic adhesion molecules and are involved in nerve regeneration. Previously, we showed that NINJ1 and p53 are mutually regulated and the NINJ1-p53 loop plays a critical role in p53-dependent tumor suppression. However, the biology of NINJ2 has not been well-explored. By using multiple in vitro cell lines and genetically engineered mouse embryo fibroblasts (MEFs), we showed that NINJ2 is induced by DNA damage in a p53-dependent manner. Moreover, we found that the loss of NINJ2 promotes p53 expression via mRNA translation and leads to growth suppression in wild-type p53-expressing MCF7 and Molt4 cells and premature senescence in MEFs in a wild-type p53-dependent manner. Interestingly, NINJ2 also regulates mutant p53 expression, and the loss of NINJ2 promotes cell growth and migration in mutant p53-expressing MIA-PaCa2 cells. Together, these data indicate that the mutual regulation between NINJ2 and p53 represents a negative feedback loop, and the NINJ2-p53 loop has opposing functions in wild-type p53-dependent growth suppression and mutant p53-dependent growth promotion.

TXNDC12 inhibits pancreatic tumor cells ferroptosis by regulating GSH/GGT7 and promotes its growth and metastasis.

Background: Thioredoxin domain-containing protein 12 (TXNDC12) is upregulated in a variety of tumours, including pancreatic cancer (PAAD), and its high expression is closely associated with poor prognosis. However, the regulatory mechanism of TXNDC12 in PAAD has not been reported. The aim of this study is to reveal the precise mechanism of TXNDC12 in regulating PAAD progression. Methods: The expression of TXNDC12 in pan-cancer as well as PAAD was verified by TCGA and GTEx databases, Western blot and RT-qPCR. CCK8 assay, clone formation assay and cell cycle assay were used to observe the effect of TXNDC12 on the proliferation of PAAD cells, the migration and invasion capacities were verified by wound healing assay and Transwell assay. The effect of TXNDC12 on apoptosis of MIA PaCa-2 and PANC-1 cells was detected using Hochest and flow cytometry. Finally, the interaction of TXNDC12 with GGT7 was predicted by STRING database and confirmed by CO-IP assay, the effect of TXNDC12 on ferroptosis through GGT7 was evaluated by GSH assay, MDA assay, ROS assay and Western blot. Results: TXNDC12 is upregulated in PAAD tissues, and patients with high TXNDC12 levels generally have shorter survival times. Knockdown of TXNDC12 significantly inhibited the proliferation, migration and invasion and promoted apoptosis of MIA PaCa-2 and PANC-1 cells. Mechanistically, knockdown of TXNDC12 resulted in a decrease in intracellular GSH content and an increase in GSSG content, as well as elevated levels of pro-ferroptosis factors, such as MDA and ROS. STRING database predicted that TXNDC12 interacts with GGT7, and CO-IP assay was used to validate this result. Finally, the effect of knocking down TXNDC12 on pancreatic cancer cell functions was able to be reversed by overexpression of GGT7. Conclusion: TXNDC12 inhibits ferroptosis in PAAD cells through the GSH/GGT7 axis thereby promoting their development.

Sulforaphane regulates cell proliferation and induces apoptotic cell death mediated by ROS-cell cycle arrest in pancreatic cancer cells.

Pancreatic cancer (PC), sometimes referred to as pancreatic ductal adenocarcinoma (PDAC), is a major cause of global mortality from cancer. Pancreatic cancer is a very aggressive and devastating kind of cancer, characterized by limited options for therapy and low possibilities of survival. Sulforaphane (SFN), a naturally occurring sulfur-containing compound, is believed to possess anti-inflammatory, anti-obesity, and anti-cancer characteristics. However, efficient preventative and treatment measures are essential and SFN has been studied for its ability to suppress pancreatic cancer cell proliferation and induce apoptosis. Here, SFN induced cytotoxicity and apoptosis in PDAC cell lines such as MIA PaCa-2 and PANC-1 cells, as evaluated by cytotoxicity, colony formation, western blot analysis, fluorescence-activated cell sorting (FACS), reactive oxygen species (ROS) detection, caspase-3 activity assay, immunofluorescence assay, and mitochondrial membrane potential assay. In MIA PaCa-2 and PANC-1 cells, SFN inhibited cell survival and proliferation in a dose-dependent manner. The activation of caspase zymogens results in cleaved PARP and cleaved caspase-3, which is associated with an accumulation in the sub G1 phase. Furthermore, SFN increased ROS level and γH2A.X expression while decreasing mitochondrial membrane potential (ΔΨm). Notably, the ROS scavenger N-Acetyl-L-cysteine (NAC) was shown to reverse SFN-induced cytotoxicity and ROS level. Subsequently, SFN-induced cell cycle arrest and apoptosis induction as a Trojan horse to eliminate pancreatic cancer cells via ROS-mediated pathways were used to inhibit pancreatic cancer cells. Collectively, our data demonstrates that SFN-induced cell death follows the apoptosis pathway, making it a viable target for therapeutic interventions against pancreatic cancer.