Growth Of Colon Cancer Cells Research Articles

Magnetomechanical Stress-Induced Colon Cancer Cell Growth Inhibition

The application of magnetomechanical stress in cells using internalized magnetic nanoparticles (MNPs) actuated by low-frequency magnetic fields has been attracting considerable interest in the field of cancer research. Recent developments prove that magnetomechanical stress can inhibit cancer cells’ growth. However, the MNPs’ type and the magnetic field’s characteristics are crucial parameters. Their variability allows multiple combinations, which induce specific biological effects. We previously reported the antiproliferative effects induced in HT29 colon cancer cells by static-magnetic-field (200 mT)-actuated spherical MNPs (100 nm). Herein, we show that similar growth inhibitory effects are induced in other colon cancer cell lines. The effect of magnetomechanical stress was also examined in the growth rate of tumor spheroids. Moreover, we examined the biological mechanisms involved in the observed cell growth inhibition. Under the experimental conditions employed, no cell death was detected by PI (propidium iodide) staining analysis. Flow cytometry and Western blotting revealed that G2/M cell cycle arrest might mediate the antiproliferative effects. Furthermore, MNPs were found to locate in the lysosomes, and a decreased number of lysosomes was detected in cells that had undergone magnetomechanical stress, implying that the mechanical activation of the internalized MNPs could induce lysosome membrane disruption. Of note, the lysosomal acidic conditions were proven to affect the MNPs’ magnetic properties, evidenced by vibrating sample magnetometry (VSM) analysis. Further research on the combination of the described magnetomechanical stress with lysosome-targeting chemotherapeutic drugs could lay the groundwork for the development of novel anticancer combination treatment schemes.

Regulation of UHRF1 acetylation by TIP60 is important for colon cancer cell proliferation

BackgroundUbiquitin-like with PHD and RING finger domains 1 (UHRF1) is upregulated in colon cancer cells and associated with silencing tumor suppressor genes (TSGs) to promote colon cancer cell proliferation.ObjectiveTo investigate epigenetic modification of UHRF1 by TIP60. Whether UHRF1 acetylation by TIP60 can induce cell proliferation in colon cancer cells.MethodsAcetylation sites of UHRF1 by TIP60 was predicted by ASEB (Acetylation Set Enrichment Based) method and identified by immunoprecipitation assay using anti-pan-acetyl lysine antibody and in vitro acetylation assay. Based on this method, UHRF1 acetylation-deficient mimic 4KR (K644R, K646R, K648R, K650R) mutant was generated to investigate effects of UHRF1 acetylation by TIP60. shRNA system was used to generate stable knockdown cell line of UHRF1. With transient transfection of UHRF1 WT and 4KR, the effects of UHRF1 4KR mutant on Jun dimerization protein 2 (JDP2) gene expression, cell proliferation and cell cycle were investigated by RT-qPCR and FACS analysis in shUHRF1 colon cancer cell line.ResultsDownregulation of TIP60-mediated UHRF1 acetylation is correlated with suppressed cell cycle progression. Acetylation-deficient mimic of UHRF1 showed poor cell growth through increased expression of JDP2 gene.ConclusionsAcetylation of UHRF1 4K residues by TIP60 is important for colon cancer cell growth. Furthermore, upregulated JDP2 expression by acetylation-deficient mutant of UHRF1 might be an important epigenetic target for colon cancer cell proliferation.

PCDH7 knockdown potentiates colon cancer cells to chemotherapy via inducing ferroptosis and changes in autophagy through restraining MEK1/2/ERK/c-Fos axis.

Chemotherapy is a commonly utilized treatment strategy for colon cancer, a prevalent malignancy. The study intends to probe the function and mechanism of protocadherin 7 (PCDH7) in colon cancer. Gain or loss of functional assays of PCDH7 was performed. MTT and colony formation assay monitored cell proliferation. Transwell measured migration and invasion. Real-time quantitative polymerase chain reaction and western blot verified the profiles of PCDH7 and the MEK1/2/ERK/c-FOS pathway. Western blot was implemented to confirm the profiles of PP1α, MLC2, and p-MLC2 for evaluating the impact of PCDH7 on homotypic cells in cell (hocic) structures. Further, an in-vivo nude mouse model was engineered to figure out the function and mechanism of PCDH7 in tumor cell growth. As indicated by the data, PCDH7 knockdown boosted the cells' sensitivity to chemotherapy. PCDH7 overexpression facilitated their proliferation and invasion, altered autophagy, induced ferroptosis and hocic, and initiated the profile of the MEK1/2/ERK/c-FOS pathway. MEK1/2/ERK inhibition impaired the inhibitory impact of PCDH7 on colon cancer cells' chemotherapy sensitivity and dampened its pro-cancer function in the cells. In-vivo experiments displayed that PCDH7 overexpression stepped up tumor growth and pulmonary metastasis in colon cancer cells. All in all, the research has discovered that PCDH7 knockdown affects autophagy and induces ferroptosis, hence strengthening colon cancer cells' sensitivity to chemotherapy by repressing the MEK1/2/ERK/c-FOS axis.

Luteolin suppresses the growth of colon cancer cells by inhibiting the IL-6/STAT3 signaling pathway.

BackgroundDespite the remarkable progression in colon cancer treatment in recent years, the pathological mechanism underlying this disease remains unclear. This study aimed to discuss the potential of luteolin in the treatment of colon cancer, from the perspective of traditional Chinese medicine, with a particular focus on the tumor microenvironment.MethodsReverse transcription quantitative polymerase chain reaction and western blot were used to analyze the effects of luteolin on interleukin (IL)-6/signal transducer and activator of transcription 3 (STAT3)/Phospho-STAT3. Enzyme-linked immunosorbent assay was used to analyze the protein secretion of IL-6. Proliferation and transwell assays were used to analyze the growth and migration of luteolin and IL-6 in colon cancer cells, respectively.ResultsStimulation with lipopolysaccharides (LPS) promoted the M1 polarization of macrophages and increased the expression and secretion of IL-6. However, the presence of luteolin inhibited the effects of LPS. M1 polarization increased the proliferation rate, migration and invasion ability, and phosphorylation of STAT3 in colon cancer cells (SW620 and SW480). Luteolin inhibited these effects by reducing M1 polarization. To confirm that the action of luteolin is mediated by IL-6/STAT3 signaling, we treated SW620 and SW480 cells with recombinant IL-6 protein and anti-IL-6 antibody. IL-6 was observed to promote cell proliferation, enhance migration and invasion, and increase STAT3 phosphorylation. The opposite effect was observed with the anti-IL-6 antibody. In addition, IL-6 promoted LPS-induced M1 polarization, while the anti-IL-6 antibody enhanced the decrease in luteolin-induced M1 polarization.ConclusionsLuteolin suppressed the growth and migration/invasion potential of colon cancer cells by inhibiting the IL-6/STAT3 signaling pathway.

Ferroptosis-induced anticancer effect of resveratrol with a biomimetic nano-delivery system in colorectal cancer treatment

Ferroptosis is a novel form of programmed cell death impelled by iron-dependent lipid peroxidation, which may be a potential strategy for cancer therapy. Here we demonstrated for the first time that Resveratrol (RSV), a traditional Chinese medicine (TCM) chemical monomer, could effectually inhibit the growth of colon cancer cells through the ROS-dependent ferroptosis pathway. Mechanistically, RSV evoked the increase of reactive oxygen species and lipid peroxidation in colorectal cancer cells, and eventually lead to ferroptosis. Furthermore, RSV could promote ferroptosis by downregulating the expression of the channel protein solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4). To improve the delivery efficiency of RSV, a biomimetic nanocarrier was developed by coating RSV-loaded poly(ε-caprolactone)–poly(ethylene glycol) (PCL-PEG) nanoparticles with erythrocyte membrane (RSV-NPs@RBCm). The RSV-NPs@RBCm provide the possibility to escape macrophage phagocytosis and have a long circulation effect. In addition, when coupled with a tumor-penetrating peptide iRGD, which could trigger enhanced tissue penetration tumor-specifically, the delivery of RSV-NPs@RBCm into tumors would be significantly improved results from the in vivo study demonstrated an excellent treatment efficacy for CRC. Altogether, our study highlighted the therapeutic potential of RSV as a ferroptosis-inducing anticancer agent and when loaded into a biomimetic nanoplatform, it might pave the way for the application of RSV loaded nanosystems for colorectal cancer treatment.

Modulation of POPDC1 Expression by Phenothiazine and Trifluoperazine Suppress Colon Cancer Growth and Migration.

The aim of this study was to investigate the effects of CaM antagonist, PTZ, and TFP on cell proliferation and migration of colon cancer cells and its impact on POPDC protein expression. The 50% inhibitory concentration (IC50) of PTZ and TFP in SW1116, SW480, HCT-15, and COLO205 colon cancer cell lines are measured using MTT. Western blot and immunocytochemistry were used to determine the expression of PCNA, cyclin D1 (CD1), and POPDC proteins. Cell migration was observed using a scratch wound-healing assay. Treatment with PTZ and TFP inhibited colon cancer cells growth in a dose-dependent manner. PTZ and TFP significantly inhibited the activation of proliferation markers, PCNA and CD1, and the migration of colon cancer cells. Furthermore, POPDC protein was significantly suppressed in all cell types of colon cancer, particularly in SW480. Finally, the CaM antagonist upregulates the POPDC1 expression in colon cancer cells. These findings suggest that CaM antagonists suppress colon cancer cells proliferation via downregulation of CD1 and PCNA. In addition, POPDC protein could be used as a biomarker in colon cancer, and CaM antagonist could be used to regulate POPDC1 expression. This study suggests that targeting POPDC1 with CaM inhibition could be a potential therapeutic strategy for colon cancer treatment.<br />.

Small molecules to regulate the GH/IGF1 axis by inhibiting the growth hormone receptor synthesis.

Growth hormone (GH) and insulin‐like growth factor‐1 (IGF1) play an important role in mammalian development, cell proliferation and lifespan. Especially in cases of tumor growth there is an urgent need to control the GH/IGF1 axis. In this study we screened a 38,480-compound library, and in two consecutive rounds of analogues selection, we identified active lead compounds based on the following criteria: inhibition the GH receptor (GHR) activity and its downstream effectors Jak2 and STAT5, and inhibition of growth of breast and colon cancer cells. The most active small molecule (BM001) inhibited both the GH/IGF1 axis and cell proliferation with an IC50 of 10‐30 nM of human cancer cells. BM001 depleted GHR in human lymphoblasts. In preclinical xenografted experiments, BM001 showed a strong decrease in tumor volume in mice transplanted with MDA‐MB‐231 breast cancer cells. Mechanistically, the drug acts on the synthesis of the GHR. Our findings open the possibility to inhibit the GH/IGF1 axis with a small molecule.

BRD9 is an essential regulator of glycolysis that creates an epigenetic vulnerability in colon adenocarcinoma.

The intensive interplay between aberrant epigenetic events and metabolic remodeling represents one of the hallmarks of tumors, including colon cancer. The functions of Bromodomain Containing Protein BRD-9 in colon cancer remains indefinite. We aimed to identify the biological roles and clinical significance of BRD9 in colon cancer. The univariate- and multi-variate Cox regression models were used to screen risk epigenetic regulators. Kaplan-Meier analysis and Pearson correlation analysis were used to assess clinical significance of BRD9. CCK-8 assays, colony formation assay, Transwell, and soft-agar assay were performed to determine the in vitro roles of BRD9. The oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) of colon cancer cells were evaluated by a Seahorse XF Extracellular Flux Analyzer. In vivo models and RT-qPCR, western blotting, and Chromatin Immunoprecipitation (ChIP) assay were conducted to explore the functional roles of BRD9 in COAD. In the study, we detected the expressions of 662 epigenetic regulators in COAD and identified a series of 42 hazard epigenetic factors with p < 0.05. Low-throughput MTT assays highlighted that BRD9 is an essential target, and targeting BRD9 could reduce significant decreases of cell growth. BRD9 overexpression could notably elevate proliferation and migration potentialities, whereas, BRD9 ablation abolished these effects. Mechanistically, functional enrichment analysis indicated the potential associations between BRD9 and glycolysis metabolism. In addition, BRD9 epigenetically coordinates the H3K27ac modifications on the promoter regions of ENO2 and ALDOC, inducing enhanced glycolysis activity. Lastly, I-BRD9 could significantly suppress the growth of colon cancer cells in vitro and in vivo. Together, our study revealed previously unidentified roles of BRD9 in colon cancer metabolism and tumor progression, indicating that BRD9 could be a valuable therapeutic target for COAD patients.

AMP-activated protein kinase β1 or β2 deletion enhances colon cancer cell growth and tumorigenesis.

Abnormal metabolism is a major hallmark of cancer and has been validated as a therapeutic target. Adenine monophosphate-activated protein kinase (AMPK), an αβγ heterotrimer, performs essential functions in cancer progression due to its central role in maintaining the homeostasis of cellular energy. While the contributions of AMPKα and AMPKγ subunits to cancer development have been established, specific roles of AMPKβ1 and AMPKβ2 isoforms in cancer development are poorly understood. Here, we show the functions of AMPKβ1 and AMPKβ2 in colon cancer. Specifically, deletion of AMPKβ1 or AMPKβ2 leads to increased cell proliferation, colony formation, migration, and tumorigenesis in HCT116 and HT29 colon cancer cells. Interestingly, the AMPKβ1 and AMPKβ2 isoforms have slightly different effects on regulating cancer metabolism, as colon cancer cells with AMPKβ1 knockout showed decreased rates of glycolysis-related oxygen consumption, while AMPKβ2 deletion led to enhanced rates of oxygen consumption due to oxidative phosphorylation. These results demonstrate that functional AMPKβ1 and AMPKβ2 inhibit growth and tumorigenesis in colon cancer cells, suggesting their potential as effective targets for colon cancer therapy.

SFPQ promotes RAS-mutant cancer cell growth by modulating 5'-UTR mediated translational control of CK1α.

Oncogenic mutations in the RAS family of small GTPases are commonly found in human cancers and they promote tumorigenesis by altering gene expression networks. We previously demonstrated that Casein Kinase 1α (CK1α), a member of the CK1 family of serine/threonine kinases, is post-transcriptionally upregulated by oncogenic RAS signaling. Here, we report that the CK1α mRNA contains an exceptionally long 5′-untranslated region (UTR) harbouring several translational control elements, implicating its involvement in translational regulation. We demonstrate that the CK1α 5′-UTR functions as an IRES element in HCT-116 colon cancer cells to promote cap-independent translation. Using tobramycin-affinity RNA-pulldown assays coupled with identification via mass spectrometry, we identified several CK1α 5′-UTR-binding proteins, including SFPQ. We show that RNA interference targeting SFPQ reduced CK1α protein abundance and partially blocked RAS-mutant colon cancer cell growth. Importantly, transcript and protein levels of SFPQ and other CK1α 5′-UTR-associated RNA-binding proteins (RBPs) are found to be elevated in early stages of RAS-mutant cancers, including colorectal and lung adenocarcinoma. Taken together, our study uncovers a previously unappreciated role of RBPs in promoting RAS-mutant cancer cell growth and their potential to serve as promising biomarkers as well as tractable therapeutic targets in cancers driven by oncogenic RAS.

Retraction: Exosomes function as nanoparticles to transfer miR-199a-3p to reverse chemoresistance to cisplatin in hepatocellular carcinoma.

This Retraction follows an Expression of Concern relating to this article previously published by Portland Press.This article is being retracted from Bioscience Reports at the request of the authors following receipt of a notification from a reader, alerting the Editorial Office to potential issues surrounding the scientific validity of this paper, including identical image panels that appear across multiple publications. Figure panels 3C and 3D contains identical images with the following papers: ‘The Long Non-coding RNA LINC01705 Regulates the Development of Breast Cancer by Sponging miR-186-5p to Mediate TPR Expression as a Competitive Endogenous RNA’ (Figure 7C and 7D respectively; https://doi.org/10.3389/fgene.2020.00779), ‘Circular RNA circ-0016068 Promotes the Growth, Migration, and Invasion of Prostate Cancer Cells by Regulating the miR-330-3p/BMI-1 Axis as a Competing Endogenous RNA’ (Figure 2C and 2D respectively; https://doi.org/10.3389/fcell.2020.00827), and ‘LncRNA SNHG4 promotes osteosarcoma proliferation and migration by sponging miR‐377‐3p’ (Figure 2D; https://doi.org/10.1002%2Fmgg3.1349). Figure panels 3E and 3F share identical images with those of article ‘Long Non-Coding RNA ELFN1-AS1 Promoted Colon Cancer Cell Growth and Migration via the miR-191-5p/Special AT-Rich Sequence-Binding Protein 1 Axis’ (Figure 3C; (https://doi.org/10.3389%2Ffonc.2020.588360). The authors wish to retract the article. The Editor-in-Chief and Editorial Board agree with the retraction.

A peptoid-based inhibitor of protein arginine methyltransferase 1 (PRMT1) induces apoptosis and autophagy in cancer cells

Protein arginine methyltransferases (PRMTs) are S-adenosylmethionine-dependent enzymes that transfer a methyl group to arginine residues within proteins, most notably histones. The nine characterized PRMT family members are divided into three types depending on the resulting methylated product: asymmetric dimethylarginine (Type I PRMT), symmetric dimethylarginine (Type II PRMT), or monomethylated arginine (Type III PRMT). In some cancers, the resulting product can lead to either increased or decreased transcription of cancer-related genes, suggesting PRMT family members may be valid therapeutic targets. Traditionally, peptide-based compounds have been employed to target this family of enzymes, which has resulted in multiple tool and lead compounds being developed. However, peptide-based therapeutics suffer from poor stability and short half-lives, as proteases can render them useless by hydrolytic degradation. Conversely, peptoids, which are peptide-mimetics composed of N-substituted glycine monomers, are less susceptible to hydrolysis, resulting in improved stability and longer half-lives. Herein, we report the development of a bioavailable, peptoid-based PRMT1 inhibitor that induces cell death in MDA468 and HCT116 cancer cell lines while not exhibiting any significant impact on nontumorigenic HepaRG or normal human mammary epithelial cells. Furthermore, the inhibitor described herein appears to induce both apoptosis and autophagy, suggesting it may be a less toxic cytostatic agent. In conclusion, we propose this peptoid-based inhibitor has significant anticancer and therapeutic potential by reducing cell viability, growth, and size in breast and colon cancer. Further experimentation will help determine the mechanism of action and downstream effects of this compound.

The Potential Mechanisms of Cinobufotalin Treating Colon Adenocarcinoma by Network Pharmacology.

Network pharmacology, as a novel way using bioinformatics to explore drug targets and interactions in cancer, broadens our understanding of drug action, thereby facilitating drug discovery. Here, we utilized network pharmacology to explore the role and mechanism by which cinobufotalin functions in colon adenocarcinoma (COAD). We found that cinobufotalin represses the growth and proliferation of colon cancer cells, and integrated public databases for targets reported to be associated with COAD, together with those predicted to be targets of cinobufotalin. Targets overlapped between COAD-associated proteins and cinobufotalin target proteins were used to filter candidate targets of cinobufotalin in COAD. The following proteins were thought to occupy a key position in COAD-cinobufotalin target networks: SRC, PIK3R1, MAPK1, PIK3CA, HSP90AA1, CTNNB1, GRB2, RHO1, PTPN11, and EGFR. The networks regulated by cinobufotalin were involved mainly in extracellular signal stimulation and transduction, including MAPK signaling pathway, PI3K-AKT signaling pathway, and JAK-STAT signaling pathway. Besides, transcriptome sequencing results also indicated that cinobufotalin inhibits the response of colon cancer cells to extracellular stimulation and promotes cell apoptosis. Molecular docking results showed that cinobufotalin matches in the pocket of the top candidate cinobufotalin target proteins (SRC, PIK3R1, MAPK1 and PIK3CA). These findings demonstrate cinobufotalin can be developed as potential anti-cancer therapeutics.

Abstract 4044: An extract of olive oil wastewater enhances chemotherapy effects on breast cancer cells without exacerbating cardiovascular toxicity

Abstract Background: In cancer patients receiving chemotherapeutic agents, cardiovascular toxicities still remains one of the most undesirable side effects. One of the best known cardiotoxic agents is doxorubicin, a very powerful chemotherapeutic molecules for breast cancer. Extra-virgin olive oil (EVOO) is rich in cancer preventive polyphenols endowed with anti-inflammatory, anti-oxidant activities which could exert protective effects on heart cells. A very interesting derivative of EVOO preparation is represented by purified extracts from olive mill waste waters (OMWW) rich in polyphenols. Here, we have investigated the anti-cancer activity of a OMWW preparation, named A009, on breast cancer cells when combined with chemotherapeutics, as well as its potential cardioprotective activities. We had previously reported additive effects with cisplatin in prostate cancer cells. In previous studies we have shown that the combination of A009 with cisplatin or 5-FU was effective in decreasing prostate and colon cancer cell growth, while it did not further reduce growth of rat cardiomyocytes also treated with cisplatin or 5-FU. Here we used 5-fluorouracil as comparison. Methods: Combination of A009 and chemotherapy was investigated in vitro on human breast cancer cell lines BT459, MDA-MB-234. The cardioprotective effects of the A009 extract were tested on H9C2 (cardiomyocytes) cells co-exposed to doxorubicin or 5-fluorouracil and in zebrafish embryos. Results: Adding A009 to doxorubicin or 5-FU was effective in decreasing breast cancer cell growth in monolayer. Breast tumor spheroids morphologically appeared less stable and with reduced diameter when treated with A009 extracts and with the chemotherapeutic agents 5-FU or Doxo, additive effects were observed. A009 mitigated toxicity of doxorubicin or 5-FU on rat cardiomyocytes cells H9C2. Cardioprotective effects were observed by the combination of OMWW extracts with Doxorubicin in Zebrafish embryos. In human cardiomyocytes, we observed 5-FU induced upregulation of the proinflammatory IL6 mRNA, which was reduced by OMWW treatment. Conclusions: Our study demonstrates that the polyphenol rich purified A009 extracts enhance the effect of chemotherapy of doxorubicin and 5-FU on breast cancer cells but mitigates chemotherapy adverse effects on heart in vivo and on cardiomyocytes, appearing as a potential cardio-oncological prevenzion agent. Citation Format: Adriana Albini, Marco M. Festa, Denisa Baci, Nadia Benedetto, Karolina Gutmanska, Nicoletta Macrì, Giovanna Finzi, Fausto Sessa, Serena Zacchigna, Antonino Bruno, Douglas M. Noonan. An extract of olive oil wastewater enhances chemotherapy effects on breast cancer cells without exacerbating cardiovascular toxicity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4044.

Abstract 5632: Combinatorial epigenetic targeting of PRC2 complexes upregulates MHC antigen presentation components in melanoma and gastrointestinal cancer cells

Abstract Low tumor immunogenicity is associated with immune escape, immunotherapy resistance, and poor patient survival [1-3]. Major histocompatibility complex (MHC) antigen presentation pathways (APPs) play a crucial role in promoting tumor T-cell recognition and initiating antitumoral immune responses. However, epigenetic silencing of APPs is a common mechanism in various cancers, including melanoma and gastrointestinal malignancies [3,4]. In the current investigation, mouse melanoma (B16/OVA) and human colon cancer (LOVO and HCT116), small intestine cancer (HUTU80), and normal colonic epithelial (CCD841) cell lines were treated with epigenetic drug candidates. As reported [5], a decrease in histone H3K27 methylation marks via polycomb repressive complex 2 (PRC2) inhibitors, as well as altered histone acetylation status from histone deacetylase 3 (HDAC3)-specific inhibition, increased the expression of APP components, based on immunoblotting and RT-qPCR experiments. Normal colonic epithelial cells showed resistance to the treatments, indicating cancer cell-specific effects of the test agents. In B16/OVA cells, flow cytometry and enzyme linked immunosorbent assays corroborated that HDAC3 and/or PRC2 inhibitor combinations increased cell surface occupancy of MHC-I complexes and increased CD8+ T-cell activation. These findings have implications for the clinical application of next-generation combinatorial epigenetic agents [6,7], targeted towards increased tumor immunogenicity and enhanced efficacy of new immunoepigenetic strategies. Supported in part by NCI grant CA122959, by the John S. Dunn Foundation, and by a Chancellor’s Research Initiative.

Abstract 5713: Alternative splicing of the chromatin modifier gene BAZ1A in colorectal cancer

Abstract Bromodomain Adjacent to Zinc finger Domain 1A (BAZ1A) is a non-catalytic subunit of the ATP-dependent chromatin assembly factor that regulates key cellular processes such as DNA replication, chromatin assembly, DNA repair, and transcriptional gene regulation (1). Defective DNA repair is a hallmark of cancer etiology, and BAZ1A is one of the deregulated proteins in colorectal cancer. The BAZ1A transcript exhibits full-length and truncated forms, generated via alternative splicing of exon-13. We observed that the histone deacetylase inhibitor sulforaphane (SFN) modulated alternative splicing of BAZ1A in human colon cancer cells by increasing the relative expression of the short vs. the long transcript. Cell Cycle and Apoptosis Regulator 2 (CCAR2) and Zinc finger protein 326 (ZIRD) are components of the DBIRD complex that integrates alternative splicing and the rate of transcript elongation (2). Knockdown of DBIRD members, including ZIRD and splicing factor hnRNPA1, downregulated expression of BAZ1A long form, whereas the BAZ1A short form was unaltered. Previous studies in SFN-treated colon cancer cells revealed that the BAZ1A bromodomain recognized a novel K97 acetylation site in CCAR2 (3). Co-immunoprecipitation analyses revealed that CCAR2 and BAZ1A interacted with each other in the presence and absence of SFN. On investigating the involvement of CCAR2 in BAZ1A alternative splicing, SFN treatment increased the expression of both BAZ1A long and short forms in CCAR2-/- HCT116 colon cancer cells. Although the total expression of BAZ1A was influenced by CCAR2 loss, alternative splicing of BAZ1A was independent of DBIRD complex-mediated regulation. Pursuing the role of p53 and p21 in BAZ1A alternative splicing, SFN treatment increased the expression of BAZ1A short form in p21-/- HCT116 cells, whereas this was impaired in p53-/- HCT116 cells. Overall, this investigation provided mechanistic insights into the regulation of alternative splicing in SFN-treated colon cancer cells, and BAZ1A functionalities that might be targeted via next-generation combinatorial epigenetic agents (4). Supported in part by NCI grant CA122959, by the John S. Dunn Foundation, and by a Chancellor’s Research Initiative.

Abstract 1582: Chloroquine inhibites Rab11 mediated E-cadherin transport in collective colon cancer cell migration

Abstract Cell migration is regulated by multiple molecular pathways to change the morphology from epithelial to mesenchymal type and is important in cancer metastasis. In has been demonstrated epithelial mesenchymal transition (EMT) is related to E-cadherin expression level. The loss of E-cadherin expression results in tumor proliferation and metastasis. Recently, studies have been demonstrated the collective cancer cell migration which expresses high E-cadherin is a powerful mechanism of metastasis. Therefore, the role of E-cadherin in cancer metastasis is still not clear. Clathrin-mediated endocytosis (CME) was shown to regulate E-cadherin turnover on the membrane and the function of lysosome is also associated with cell vesicle trafficking, however, the role of lysosome in collective cell migration is not known. This study is investigating the role of lysosome in regulating E-cadherin dynamics through vesicle trafficking in collective colon cell migration. In the experiment, we used colon cancer cells with epithelial morphology and observed the relation of E-cadherin with endocytic protein clathrin, Rab5 and the recycling protein Rab11 in collective migrated cells. In the result, inhibition of lysosome activity by chloroquine treatment has great suppression effect on anchorage independent cell growth and inhibited collective cell migration. We observed that nocodazole treatment inhibited clathrin-mediated endocytosis, which caused E-cadherin to accumulate on the cell membrane. Western blot and confocal microscopy demonstrated chloroquine treatment induced Rab11 expression and accumulated in the cytosol which affected E-cadherin turnover. Our results demonstrated inhibits lysosome activity can suppress colon cancer cell growth and collective migration through lysosome mediated E-cadherin translocation. Chloroquine may be the potential treatment for colon cancer therapy. keywords: colon cancer, collective cell migration, E-cadherin, vesicle trafficking, lysosome Citation Format: Xiang-Ling Hou, Hui Min Koo, Yu-Cheng Weng, Yi-Wen Lu, Viriya Adhiguna Winarso, Yu-Lin Li, Wei-Ting Chao. Chloroquine inhibites Rab11 mediated E-cadherin transport in collective colon cancer cell migration [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1582.

Abstract 1626: The orthotopic mouse study of cetuximab and dasatinib treatment on BRAF mutated colon cancer cells

Abstract Colorectal cancer is one of the most common cancer in the world. The mortality rate is the third among the top ten cancers. Among colorectal cancer patients, about 65-75% of patients have overexpression of epithelial growth factor receptors (EGFR). The antibody drug cetuximab that inhibits EGFR has also been developed. Moreover, overexpression of src protein is found in about 80% of patients with colorectal cancer. Higher levels of Src expression is related to the metastasis of colon cancer. Dasatinib is an oral taken tyrosine kinase inhibitor to inhibit the src phosphorylation. Therefore, in this study, the mechanism of cetuximab and dasatinib combined treatment in the orthotopic mouse model is investigated. The in vivo mechanism of EGFR and E-cadherin crosstalk in the mouse model is discussed. In this study, HT-29 colon cancer cells with BRAF V600E mutation were orthotopically injected into the cecum wall of BALB/c nude male mice. Two weeks later, cetuximab, dasatinib, and combined treatment of cetuximab and dasatinib were applied for three weeks. The tumor sizes were then recorded after sacrificed. Tumor Tissue were processed for tissue section with H&amp;E staining. Immunohistochemistry (IHC) was applied to detect EGFR, p-Src, E-cadherin with specific antibodies. The protein expression levels were achieved by Western blot. In the results, the tumor size was smaller in cetuximab and dasatinib combined treated group. In IHC staining, the E-cadherin expression were not apparent in primary tumor site, however, were abundant in migrated cells. P-src expression was reduced in the dasatinib treated group and combined treatment group. In western blot result, the E-cadherin was increased after the treatment of dasatinib, and the p-src expression was inhibited after dasatinib treatment and combined treatment. Our results demonstrated cetuximab combined with dasatinib has the better result of suppression of BRAF mutated colon cancer cell growth and metastasis in the orthotopic mouse model. Citation Format: Yu-Cheng Weng, Yu-Lin Li, Xiang-Ling Hou, Hui Min Koo, Yi-Wen Lu, Viriya Adhiguna Winarso, Chia-Wen Lin, Wei-Ting Chao. The orthotopic mouse study of cetuximab and dasatinib treatment on BRAF mutated colon cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1626.

Abstract 5505: ADAM10-targeting CAR-T cells inhibit colon cancer cell growth in vivo

Abstract Chimeric antigen receptor (CAR) T cell therapy has demonstrated a high degree of efficacy in patients with hematological malignancies such as acute lymphatic leukemia. However, its efficacy in solid tumors remains to be demonstrated. There are a number of issues currently limiting therapeutic treatment of solid tumors with CAR-T cells, none more important than target antigen selection. This is a major challenge in solid tumors due to their heterogenous characteristics and the potential for off-cancer effects. ADAM10, A Disintegrin And Metalloproteinase 10, plays critical roles in a wide range of pathophysiological processes during development and inflammation. These proteolytically active multifunctional proteins act as sheddases by cleaving transmembrane-bound proteins such as growth factors, adhesion molecules and chemokine receptors, which can then contribute to migration and invasion of cancer cells. An active form of ADAM10 that has undergone a conformational change has been identified in several cancer types, particularly colorectal cancer. In this study, a novel CAR was generated based on a previously characterized cancer-specific ADAM10 antibody. ADAM-10-targeting CAR-T cells were manufactured using T cells from the peripheral blood of the healthy donors. The CAR-T cells displayed the naïve and central memory phenotype that has been shown to differentiate and proliferate within tumor microenvironments, with little expression of exhaustion markers. These CAR-T cells were capable of killing several human colorectal tumor cell lines in vitro, assessed in a bioluminescence-based cytotoxicity assay. Furthermore, treatment of NSG mice bearing human LoVo colon cancer cell tumors with ADAM-10-targeting CAR-T cells led to significant inhibition of tumor growth compared with either untransduced control T cells or PBS treatment. Overall, these data suggest that targeting ADAM-10 via CAR-T cell therapy is a promising novel avenue of treatment of colorectal cancer. Citation Format: Elaheh Rohani Rad, Jade Foeng, Dylan McPeak, Timona Tyllis, Caitlin Abbott, Veronika bandara, Silvana Napoli, Batjargal gundsambuu, Simon Barry, Timothy Sadlon, shaun McColl. ADAM10-targeting CAR-T cells inhibit colon cancer cell growth in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5505.

Abstract 5949: Aspirins metabolites inhibit human colon cancer cell growth: Potential role in colorectal cancer prevention

Abstract Aspirin’s role in colorectal cancer (CRC) prevention is evidential from several epidemiological data. Numerous theories and targets have been proposed, a consensus has not been reached regarding its mechanism of action. One of the unexplored area in aspirin’s CRC prevention is the role of Dihydroxy benzoic acids (DHBAs), which are generated from aspirin’s metabolism by gut microflora and cytochrome P450 (CYP450). Out of the screened DHBAs, 2,3-DHBA and 2,5-DHBA showed concentration dependent inhibition of CDK1, CDK2, CDK4 and CDK6 enzyme activity in-vitro. We demonstrated that 2,3-DHBA and 2,5-DHBA inhibits CDK-1 enzyme activity beginning at 500 µM, while CDK2 and CDK4 activity was inhibited only at higher concentrations (&amp;gt;750 µM). 2,3-DHBA inhibited CDK6 enzyme activity from 250 µM, while 2,5-DHBA inhibited its activity &amp;gt;750 µM. Using colony formation assays, we further demonstrated the role of 2,3-DHBA and 2,5-DHBA in cancer cell cycle inhibition in 3 different cancer cell lines. Out of the 2 DHBAs, 2,5-DHBA was highly effective in inhibiting clonal formation in HCT-116 and HT-29 CRC cell lines (250-500 µM), and in the MDA-MB-231 breast cancer cell line (~100 µM); whereas both aspirin and salicylic acid failed to inhibit all four CDKs and colony formation. Based on the present results, it is suggested that 2,3-DHBA and 2,5-DHBA may contribute to the chemopreventive properties of aspirin, possibly through the inhibition of CDKs. The present data and the proposed mechanisms should open new areas for future investigations. Citation Format: Poojitha Tummala, Ranjini Sankaranarayanan, Rakesh Dachineni, Jayarama Gunaje Bhat. Aspirins metabolites inhibit human colon cancer cell growth: Potential role in colorectal cancer prevention [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5949.