Inhibit Cancer Cell Growth Research Articles

Abstract 5695: miR-5787 suppresses cancer cell growth as a Fe3O4-nanoparticles induced pivotal miRNA

Abstract Nanotechnology offers great potential for cancer diagnosis and treatments. Especially, nanoparticles (NPs) have been examined and utilized as drug delivery systems, hyperthermia and combination therapy. We have examined and reported the combined effects of Fe3O4-nanoparticles (Fe3O4-NPs) with chemotherapeutic agents on prostate cancer cell in vitro. miRNAs are an important factor in cancer progression, and elucidating the miRNA-mediated intracellular network of cancer cells could suggest new cancer treatment strategies. In this study, to identify microRNAs (miRNAs) associated with anticancer effects of Fe3O4-NPs, the comprehensive expression of miRNAs by Microarray (Agilent G4780A SuperPrint G3 Human v16 miRNA 8x60K Microarray kit) in A549 (lung cancer cell line), LNCaP (androgen-dependent prostate cancer cell line) and DU145 (androgen-independent prostate cancer cell line) under Fe3O4-NPs exposure was performed. miR-5787 was one of the increased miRNAs in three cancer cell lines under Fe3O4-NPs, and its increase in miR-5787 was due to the reactive oxygen species (ROS) production by Fe3O4-NPs. The additional analysis suggested that miR-5787 might suppressed the cancer cell growth by targeting the eIF5. In this study, we identified miR5787 as a Fe3O4-NPs induced pivotal miRNA in cancer cells, and can be used as a therapeutic target. Citation Format: Masatoshi Watanabe, Hitoshi Nakano, Chise Matsuda, Eri Usugi, Hiroshi Imai, Yoshifumi Hirokawa, Kazutoshi Iijima. miR-5787 suppresses cancer cell growth as a Fe3O4-nanoparticles induced pivotal miRNA [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 5695.

Abstract 4493: Protein structure inspired drug discovery

Abstract Introduction: Drug action is mediated by a small molecule therapeutic binding to a specific structural motif on a protein. As structure determines function, it follows that unique structural motifs are enriched for sites of unique function and high therapeutic target value. We hypothesized that protein structure constitutes high value primary information that can drive the discovery of novel therapeutic agents. Method: We developed a unique physics-based protein structure analysis platform scaled to run on a supercomputer, allowing us to consider dynamic protein flexibility and the influence of solvent upon protein structure, and to probe large protein libraries as a primary source of structure information that can support up-front structure-based screens. We developed and then probed a high resolution protein x-ray crystallographic library, created and curated by us. From a 60 million compound library, we conducted virtual screens for docking to identified sites. 8-day colony formation assays were conducted on a panel of 8 human breast, prostate, lung and colon cancer cell lines, as well as 8- and 14-day trilineage hematopoietic colony formation assays on human cord blood stem cells. Findings: From the first 180 deposited protein structures, we screened for unique protein surface structure. Structures were deemed unique if they were not otherwise known to be associated with any particular functional roles and were not the binding site of known therapeutics. Further selection included those that were clefts and possessed physical characteristics compatible with binding small chemicals whose properties have been linked to effective therapeutics. For each of 8 sites on 6 different proteins, a suite of analytics probed docking solutions from the compound library, generating a ranked list of 100 compounds for each site. Based on factors inclusive of availability and low potential for toxicity, compounds were acquired and used in in-parallel selection and de-selection functional assays. Cancer cell growth inhibition was a positive selection criterion, with additional ranking based on greater potency and broader efficacy. Bone marrow toxicity is limiting for most drugs, and inhibition of bone marrow stem cell growth was as a deselection criterion. Multiple compounds clustered around 2 sites on 2 different proteins. One compound, Dxr2-017, exhibited very high relative efficacy against colon and breast cancer cells. Evaluation of Dxr2-017 in the NCI-60 panel corroborated these findings, and showed even higher efficacy against melanoma. We demonstrated that Dxr2-017 inhibited melanoma growth with low nanomolar efficacy, while concentrations of over 2300-fold higher had only limited inhibitory effects on bone marrow stem cells. Conclusions: This study provides proof-of-principle that protein structure constitutes high value primary information that can support identification of novel therapeutics. This approach is widely applicable and expandable. Citation Format: Fangfang Qiao, T. Andrew Binkowski, Wayne Anderson, Weining Chen, Gray Schiltz, Karl Scheidt, Amarnath Natarajan, Raymond Bergan. Protein structure inspired drug discovery [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 4493.

Abstract 5963: VGLL1-derived peptides demonstrated anticancer effect by inhibiting VGLL1-TEAD4 interaction

Abstract YAP/TAZ, cofactors of TEA domain-containing transcription factor TEADs (TEAD1-4), play a key role in the HIPPO pathway, which is involved in various function including embryonic development, organ size, cell proliferation, tissue regeneration, and the development and progression of several cancers. YAP/TAZ is therefore considered as master regulators of various cancers. However, we are interested in VGLL1, a cofactor of TEAD4, because it is mainly involved in the proliferation and metastasis of various cancers, including gastric, breast, pancreatic, and ovarian cancers. In gastric cancer, VGLL1 expression is regulated by the PI3K/AKT/β-catenin pathway. VGLL1 is then phosphorylated at S84 by TGF-β/ribosomal S6 kinase 2 (RSK2) and interacts with TEAD4 to express target genes such as MMP9, cyclin D1, IGFBP3, IGFBP5 and ITGαV. which are involved in cancer malignancy. We designed S84-containing VGLL1-derived peptides (VGLL1S84 peptides, SCVP), which consist of 7 to 15 amino acids linked to CPP, a cell-penetration peptide. We evaluated SCVP to inhibit the VGLL1-TEAD4 interaction and their therapeutic potential as anticancer agents. SCVP suppressed the growth of gastric and breast cancer cells expressing high levels of VGLL1, EGFR, and/or HER2. In the RNA-seq analysis of NUGC3 to elucidate the molecular mechanisms of SCVP induced cell death, SCVP-treated cells showed gene expression changes in metabolic pathway, RAS signaling, PI3K-AKT signaling, Wnt signaling, TNF signaling, and mTOR signaling. However, RNA-seq analysis of breast cancer cells treated with SCVP showed changes in the expression of genes involved in cell cycle, DNA replication, DNA repair, and apoptosis. Then, we performed CRISPR/Cas9 screening using SCVP and sgRNA library to explore companion biomarkers and genetic interactors of VGLL1 for targeted cancer therapy. As a result, we identified several candidate genes, including ZNF292 and PLK1, as synthetic lethal genes of VGLL1. As expected, HCC70 cells with ZNF292 mutation showed increased sensitivity to SCVP. We also found that SCVP in combination and the PLK inhibitor volasertib resulted in a synergistic effect on the growth inhibition of breast cancer cells. In conclusion, we demonstrated VGLL1 as a novel target for anticancer drug development, and elucidated the molecular mechanism and therapeutic potential of the SCVP in gastric and breast cancers. Citation Format: Sangmi Ock, Changsub Lee, Wongi Jung, Ina Whang, Kyung-Soo Kim, Jongmin Han, Sujin Yim, Bo-Kyung Kim, Hong-Sub Lee, Kwan-Young Chang, Misun Won. VGLL1-derived peptides demonstrated anticancer effect by inhibiting VGLL1-TEAD4 interaction [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 5963.

Abstract 438: Inhibition of de novo lipogenesis with PUFA supplementation induces ferroptosis in advanced prostate cancer

Abstract Background: Metabolic alterations are recognized as a hallmark of cancer progression. In prostate cancer (PCa), in particular, a notable lipid reprogramming occurs with increased expression levels of multiple enzymes involved in the fatty acid synthesis pathway to fulfill the metabolic and structural demands of cancer cells. Fatty acids are vital for membrane building, ATP production through B-oxidation, and storage in lipid droplets for high-energy demands. In castration-resistant prostate cancer (CRPC), the aberrant overexpression of Fatty Acid Synthase (FASN), the rate-limiting enzyme in de novo lipogenesis (DNL), results in synthesis of saturated (palmitate) and monounsaturated fatty acids (SFA and MUFA). If DNL is inhibited, polyunsaturated fatty acids (PUFAs) are taken up from the environment. These could undergo lipid peroxidation generating reactive oxygen species (ROS) and contribute to ferroptosis. We hypothesize that combining the inhibition of DNL with the addition of exogenous PUFAs could increase cell death by ferroptosis. Methods: PCa cells (LNCaP, 22Rv1 and C4-2) and human organoids were exposed to pharmacologic FASN inhibition and PUFAs for 6 days. Cell viability, lipid peroxidation, superoxide production and, protein carbonylation as a measure of intracellular ROS as well as lipidomic profiling, were assessed. Results: FASN inhibition significantly increased lipid peroxidation and intracellular ROS, with subsequent membrane potential hyperpolarization in prostate cancer cells. These effects were partially rescued by palmitate, while FASNi supplemented with PUFA potentiated protein carbonylation. Expression levels of GPX4, the main regulator of ferroptosis, were reduced after DNL inhibition and rescued with palmitate addition. Suppression of DNL combined with supplemental addition of PUFAs resulted in significant cell growth inhibition in prostate cancer cells and organoids. Finally, lipid profiling demonstrated that the suppression of DNL triggers increased acyl chain length in phospholipid and several other lipid classes. Again, this effect was significantly potentiated when combining FASN inhibition with PUFA supplementation. Conclusion: FASN inhibition produces a cascade of intracellular events, including lipid remodeling, increased ROS production and ferroptosis, all potentiated by PUFAs. These findings provide compelling evidence for the use a combined approach involving DNL inhibition and PUFA supplementation as a novel therapeutic avenue to treat advanced prostate cancer. Citation Format: Silvia Daniele Rodrigues, Isadora Ferrari Teixeira, Pier Vitale Nuzzo, Hubert Pakula, David Nanus, Massimo Loda. Inhibition of de novo lipogenesis with PUFA supplementation induces ferroptosis in advanced prostate 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 438.

Abstract 469: PIWI-interacting RNA 50485 (piRNA-50485) is a novel lung tumor suppressor

Abstract Introduction: It is crucial to identify new driver genes and associated downstream pathways to facilitate the development of targeted therapies to effectively treat late-stage and metastatic lung cancer. One pathway involves the Ras association domain family 1 (RASSF1) gene which encodes multiple isoforms. Our laboratory has discovered that the RASSF1C isoform exhibits functional characteristics of an oncogene. We discovered that RASSF1C modulates the expression of PIWI-(Drosophila)-like 1 (PIWIL1, a stem cell renewal gene), as well as novel PIWI-interacting RNAs (piRNAs), which are regulators of the stem cell phenotype and have been linked to oncogenesis. While studying this pathway, we have identified novel piRNAs that are modulated by RASSF1C in non-small cell lung cancer (NSCLC) cells that appear to act as oncogenes or tumor suppressors. Methods: We conducted a global microarray screen to identify RASSF1C PIWI-interacting RNA (piRNA) gene targets. Several piRNA genes that are up- and down-regulated by RASSF1C were identified and the expression of selected up-regulated and down-regulated target genes were confirmed by RT-PCR. We evaluated the impact of selected piRNAs on lung cancer cell proliferation and migration in vitro. We also assessed the expression of the validated piRNA target genes in lung tumor and matched normal tissues. Host and target genes for specific piRNAs were identified using a piRNA database (piRNAdb.org). Results: Among the down-regulated piRNAs, we found that restoring piR-50485 expression drastically decreased lung cancer cell proliferation and invasion, suggesting that piR-50485 could be a potent inhibitor of lung cancer cell growth and progression. Consistent with this, we found that piR-50485 expression is significantly down-regulated in about 60% of human lung cancers. We also identified that the ZHX3 gene (a transcription repressor), which is down-regulated in human lung cancers, is the host gene for piR-50485. In addition, we identified the ZNF618 gene (a transcription co-regulator) that is up-regulated in lung tumor tissue, is a piR-50485 target gene. Consistent with this, treatment of lung cancer cells with piR-50485 mimics resulted in a significant decrease of ZNF618 protein levels, cell proliferation, and migration. Further, increased expression levels of ZHX3 are associated with higher lung cancer patient survival, while increased ZNF618 levels are associated with lower survival. Our novel findings suggest the hypothesis that the piR-50485-ZHX3-ZNF618 gene axis could negatively impact lung cancer cell growth and progression. Conclusion: Exploring the impact of the piR-50485-ZHX3-ZNF618 gene axis on lung cancer growth is a novel concept about which nothing is currently known. We are studying piR-50485 to determine if it can be an effective therapy for lung cancer metastasis, and whether it provides important prognostic information about lung cancer outcomes. Citation Format: Mark E. Reeves, Yousef G. Amaar. PIWI-interacting RNA 50485 (piRNA-50485) is a novel lung tumor suppressor [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 469.

Abstract 5944: Discovery of BH-30236: A novel macrocyclic CLK inhibitor targeting alternative splicing in cancers

Abstract Aberrant alternative splicing is a newly recognized hallmark of cancer, that has been shown to play a critical role in tumorigenesis, cancer progression, and therapeutic resistance via multiple mechanisms, including increased proliferation, decreased apoptosis, promoted migration, enhanced metastatic potential, and induced evasion of immune surveillance. Serine and arginine-rich splicing factors (SRSFs) are RNA-binding proteins (RBPs) that regulate constitutive and alternative splicing. SRSFs are often mutated or overexpressed in cancers, resulting in widespread alterations in splicing patterns. The Cdc2-like kinase (CLK) family and dual-specificity tyrosine-regulated kinase (DYRK) phosphorylate SRSFs, influencing the assembly of spliceosome machinery, exon recognition, and splicing. Therefore, targeting CLK/DYRK kinases can modulate cancer specific splicing isoforms, opening avenues for new therapeutic interventions. BH-30236 was designed as a novel orally bioavailable, ATP-competitive, macrocyclic inhibitor of CLK with IC50s of 0.134, 0.165, and 0.446 nM against CLK1, CLK2, and CLK4, respectively in enzymatic kinase assays. At clinically relevant concentrations, BH-30236 also inhibited DYRK1A/1B/2, proviral insertion site of moloney murine leukemia virus kinase 3 (PIM3), and FMS-like tyrosine kinase 3 (FLT3) with IC50s of 0.111, 0.148, 0.562, 0.115 and 0.248 nM, respectively. In cancer cells, BH-30236 impaired the phosphorylation of SRSFs, Tau and 4EBP1, the direct downstream substrates of CLK, DYRK, and PIM kinases with IC50s of 40-60 nM, ~50 nM, and ~80 nM, respectively. Furthermore, BH-30236 potently inhibited the FLT3 phosphorylation with an IC50 of 0.16 nM. Overall, BH-30236 regulated alternative splicing by primarily inducing skipped exons in favor of anti-tumor isoforms, leading to cancer cell death and growth suppression in a broad panel of cancer cell lines and in vivo efficacy studies. For example, BH-30236 potently inhibited cell proliferation with an IC50 of 0.62 nM in FLT3-ITD positive MV-4-11 cells and achieved complete tumor regression in the MV-4-11 cell-derived xenograft tumor model, even after dose cessation for 4 weeks. In MV-4-11 cells, BH-30236 increased pro-apoptosis splicing variant BCLxS, downregulated RNA expression of BCL2, MCL1, and AML stem cell markers CD33 and CD123. In addition, BH-30236 has demonstrated good human ADME and preclinical safety profiles. Collectively, the preclinical study results strongly support the clinical applications of the novel multikinase CLK inhibitor BH-30236 in hematological malignancies and solid tumors, as a single agent or in combination with other therapies. Citation Format: J. Jean Cui, Ping Jiang, Wei Deng, Dayong Zhai, Nancy Ling, Danan Li, Zhenping Wang, Yue Hu, Levan Darjania, Jeff Whitten, Evan Rogers, Eugene Rui. Discovery of BH-30236: A novel macrocyclic CLK inhibitor targeting alternative splicing in 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 5944.

Abstract 395: An alternating magnetic field suppresses tumor growth

Abstract Application of physical forces, ranging from ultrasound to electric field, is recommended in various clinical practice guidelines, including those for bone fracture or cancer treatment. However, mechanistic information for such treatments has been poorly provided, due to the lack of comprehensive study model. Here, we show an alternating magnetic field (AMF) per se exhibits direct anti-cancer effect through enhancing oxidative phosphorylation (OXPOHS) and thus metabolic reprograming. Proliferation of human glioblastoma cells (U87 and LN229), but not normal human astrocytes (NHA), was inhibited upon exposure to AMF within the narrow frequency range. Extracellular acidification rate was decreased while oxygen consumption was increased. These data indicated that AMF induced metabolic reprograming. This was accompanied by increased reactive oxygen species (ROS) production. Mouse models grafted with human glioblastoma cells showed that AMF exposure, 30 minutes per day for two weeks, suppressed the tumor growth and prolonged the overall survival. Our results suggest that the AMF exposure may be a simple strategy to inhibit cancer cell growth by utilizing oxidative stress via metabolic reprograming. Citation Format: Masanari Umemura, Taisuke Akimoto, Rafikul Islam, Kazuhito Kishi, Akane Nagasako, Rina Nakakaji, Takashi Yamaguchi, Yuto Mizuno, Soichiro Ishikawa, Tetsuya Yamamoto, Yoshihiro Ishikawa. An alternating magnetic field suppresses tumor growth [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 395.

Abstract 1352: Computational design of a cyclic peptide that inhibits the CTLA4 in T cells and the growth of lung carcinoma in mice

Abstract Proteins involved in immune checkpoint pathways, such as CTLA4, PD-1, and PD-L1, have become important targets for cancer immunotherapy; however, the development of small molecule drugs targeting these pathways has proven difficult due to the nature of their protein-protein interfaces. Here, using a hierarchy of computational techniques, we designed a cyclic peptide that binds CTLA4 and follow this with experimental verification of binding and biological activity, using bio-layer interferometry, cell culture, and a lung cancer mouse model in immunocompetent mice. Beginning from a template excised from the x-ray structure of the CTLA4:B7-2 complex, we generate several peptide sequences using Rosetta, a protein modelling program. These peptides are cyclized head-to-tail to improve structural and proteolytic stability and screened using molecular dynamics simulation and MM-GBSA calculation. The standard binding free energies for shortlisted peptides are then calculated in explicit-solvent simulation using a rigorous multistep Binding Free Energy Estimator (BFEE). The most promising peptide, cyc-EIDTVLTPTGWVAKRYS (hereafter CTLA4-ip), yields the standard free energy -6.6 ± 3.5 kcal/mol, which corresponds to a dissociation constant of 15 μmol/L. The binding affinity of this peptide for CTLA4 is measured experimentally (31 ± 4 μmol/L) using bio-layer interferometry. Pharmacokinetics of CTLA4-ip in a cell culture with Lewis lung carcinoma (LLC) cells and in mice revealed that this peptide is significantly more stable in both cell culture and in mice as compared to a control non-cyclic scrambled-sequence. Treatment with CTLA4-ip inhibited cancer cell growth in a co-culture of LLC cells and LLC cell-antigen primed murine T cells. Intraperitoneal administration of the CTLA4-ip (10mg/kg/day, every other day totaling 4 doses) markedly inhibited lung tumor growth in mice with an orthotropic LLC allograft model. Efficacy of the tumor growth inhibition by the CTLA4-ip was similar to that by an anti-PD-L1 antibody (10mg/kg/day, every two days totaling 3 doses). These results strongly suggest that this novel CTLA4-ip works as an immune checkpoint inhibitor to CTLA4 and is usable for lung cancer treatment. This research was supported by Kansas State University Johnson Cancer Research center (MT), Midwest Biomedical Accelerator Consortium (MT, JC), National Cancer Institute MT, JC) and the National Science Foundation (JC). Citation Format: Ravindra Thakkar, Deepa Upreti, Susumu Ishiguro, Geraldine Magnin, Keshari Sudasinghe, Anabelle Hall, Sarah DeVader, Masaaki Tamura, Jeffrey Comer. Computational design of a cyclic peptide that inhibits the CTLA4 in T cells and the growth of lung carcinoma in 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 1352.

Abstract 5966: PRT2527, a novel highly selective cyclin-dependent kinase 9 (CDK9) inhibitor, has potent antitumor activity in combination with BTK and BCL2 inhibition in various lymphoid malignancies

Abstract CDK9 is a master regulator of transcription that modulates transcription elongation via phosphorylation of RNA polymerase II. Short-term inhibition of CDK9 depletes short-lived transcripts and labile proteins such as MCL1, BFL1 and MYC to promote cancer cell death. We previously described PRT2527, a novel, potent, highly selective CDK9 inhibitor with anti-leukemic activity in various preclinical models. PRT2527 is currently under evaluation in a Phase I clinical trial in patients with relapsed/refractory hematologic malignancies (NCT05159518). Here we demonstrate PRT2527 potently inhibits cancer cell growth and induces cell death in various models of Diffuse Large B Cell Lymphoma (DLBCL), Mantle Cell Lymphoma (MCL) and Chronic Lymphocytic Leukemia (CLL), through depletion of MCL1, BFL1 and MYC. Specifically, we show that brief treatment with PRT2527 (6h) potently induces apoptosis and inhibits proliferation in DLBCL, MCL and CLL cell lines. We also show that the addition of BTK inhibitors (BTKi) or BCL2 inhibitors (BCL2i) potentiates the apoptosis response induced by PRT2527 in vitro and leads to more robust and durable responses including complete tumor regressions in DLBCL CDX and PDX models in vivo. In all studies, the combination of PRT2527 with BTKi or BCL2i is well tolerated. Mechanistically, we show that BTK inhibition upregulates BMF, an endogenous inhibitor of BCL2 and BCL-xL, driving cells towards MCL1 and BFL1 dependency in TMD-8 cells. Concurrent depletion of MCL1 and BFL1 with PRT2527 leads to complete inhibition of Bcl-2- family mediated survival signaling, potently inducing cell death. In similar fashion, Venetoclax-driven BCL2 inhibition also potentiates the anti-tumor activity of PRT2527. Consistent with these findings in vitro, we observe reduced BFL1 and MCL1 as well as increased BMF in tumors of mice treated with BTKi and PRT2527 suggesting complete Bcl-2 family inhibition. We also demonstrate potent induction of apoptosis in peripheral blood mononuclear cells isolated from patients with both treatment-naïve and relapse/refractory CLL following brief treatment with PRT2527 (6h). Co-treatment with BTKi or BCL2i further enhances the apoptotic effect of PRT2527, similarly suggesting combinatorial benefit. Additionally, we characterize the activity of PRT2527 in models of BTKi relapsed/refractory MCL where increased CDK9 dependency has previously been described. In an Ibrutinib-resistant Mino CDX model, we observe increased tumor growth inhibition following treatment with PRT2527 compared to tumors derived from parental Mino cells, suggesting PRT2527 is efficacious in BTKi-resistant MCL. Altogether these data provide a rationale for evaluating PRT2527 in combination with BTK and BCL2 inhibitors for the treatment of patients with relapsed/refractory lymphoid malignancies. Citation Format: Norman Fultang, Ashley M. Schwab, Sophia McAneny-Droz, Diane Heiser, Peggy Scherle, Neha Bhagwat. PRT2527, a novel highly selective cyclin-dependent kinase 9 (CDK9) inhibitor, has potent antitumor activity in combination with BTK and BCL2 inhibition in various lymphoid malignancies [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 5966.

Abstract 3256: Novel SOX2-targeting bioPROTACs for the treatment of cancers

Abstract Targeted protein degradation (TPD) technology has been developed showing the therapeutic potential to modulate historically ‘undruggable’ disease-associated proteins. Currently, proteolysis targeting chimeras (PROTACs) using small-molecule binders represent the TPD field, and PROTAC-induced proximity between target proteins and E3 ligases enables specific degradation of target proteins. However, substantial amounts of clinically relevant cancer targets such as transcription factors lack active sites or allosteric binding pockets for small molecules which challenges the development of classical PROTACs for these targets. SOX2 is one of the pluripotency transcription factors and has been well-known for its crucial role in tumor development through promoting cancer cell survival, metastasis, stemness, and drug resistance. Numerous studies have also reported SOX2 amplification and overexpression in various tumor tissues. Thus, SOX2 has been validated as an attractive anticancer target, but directly targeting SOX2 has been proved to be difficult since SOX2 is an “undruggable” transcription factor. EPD Biotherapeutics develops EPDegTM, a next-generation engineered protein degrader platform in order to overcome the limitations of small molecule-based PROTAC. Here we report a series of SOX2-targeting bioPROTACs, being composed of a nanobody against SOX2 with high affinity and several ubiquitin E3 ligases with deletion of natural substrate binding domain to allow highly selective degradation of SOX2 protein. To evaluate the in vitro efficacy, SOX2 bioPROTACs were generated by mRNA IVT with CleanCap ® and modified uridine. First, robust degradation of SOX2 with a half-maximal degradation concentration (DC50) of the picomolar range was observed with the treatment of SOX2 bioPROTACs in multiple SOX2-overexpressing cancer cell lines. The degradation was ubiquitin- and proteosome-dependent manner, and neither nanobody nor ubiquitin E3 ligase alone affected SOX2 protein level. Then, SOX2 bioPROTACs led to significant cancer cell growth inhibition caused by apoptotic cell death with a half-maximal growth inhibition concentration (GI50) of the picomolar range. Notably, chemo-resistant cancer cell lines expressing SOX2 protein in high levels were sensitized to chemotherapy in combination with our SOX2 bioPROTACs. Furthermore, i.v. injection of one of our lead candidates formulated with LNP significantly inhibited tumor growth in the A549 xenograft model, proving the in vivo anti-tumor efficacy of SOX2 degraders for the first time in the world. Taken together, EPD’s SOX2 bioPROTACs show potent in vitro and in vivo anti-tumor efficacy as first-in-class SOX2 degraders and provide new insights for the therapeutic potential of transcription factor-degrading strategies. Citation Format: Jaehyun Choi, Saeyi Lim, Xuelian Bai, Hyerin Song, Yeonji Oh, Yeryoung Yong, Seunghyun Lee. Novel SOX2-targeting bioPROTACs for the treatment of 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 3256.

A comprehensive review uncovering the anticancerous potential of genkwanin (plant-derived compound) in several human carcinomas

Abstract Plant-derived bioactive compounds displayed major therapeutic and chemo-preventive roles in the pathogenesis of numerous chronic malignancies such as cancer and enhanced oxidative stress and inflammation. Antioxidants found in food, such as genkwanin, may reduce oxidative stress and the release of cytokines or pathways that promote inflammation. The goal of this work is to summarize the potential for anticancer effects of genkwanin, a methoxyflavone that is present in a variety of plant species. This review examined and analyzed numerous research studies on identifying, isolating, measuring, and analyzing anticancer properties of genkwanin. The mechanisms involved cellular and molecular activities at various levels, including apoptosis induction and cancer cell growth and proliferation inhibition. Preclinical studies have demonstrated genkwanin’s effects and mechanism of action; however, further research is required to investigate its therapeutic potential thoroughly. Additional research is needed to further our understanding of the pharmacodynamic effects of genkwanin. Additional toxicological study is necessary to evaluate the clinical efficacy and safety of genkwanin, which would help scientists to elucidate a potent drug candidate for cancer management.

The preventive and inhibitory effects of red raspberries on cancer

Red raspberries are gaining attention more and more for their nutritional and bioactive components, with potential health effects such as antitumor properties. This review aims to describe the antioxidant activities of red raspberries, emphasizing the role of anthocyanins and ellagitannins as primary contributors among red raspberry polyphenols; it also outlined the connection between red raspberries and their role in inhibiting cancer cell growth by regulating oxidative stress. Numerous studies suggest that red raspberries are able to block cancer cell progression by inhibiting proliferation, migration, and autophagy, as well as regulating the cell cycle, angiogenesis, and DNA damage repair. This review sheds light to the growing evidence supporting antioxidants as a crucial link between fruit consumption and cancer prevention.

Application of Doxorubicin-loaded PLGA nanoparticles targeting both tumor cells and cancer-associated fibroblasts on 3D human skin equivalents mimicking melanoma and cutaneous squamous cell carcinoma

Nanoparticle (NP) use in cancer therapy is extensively studied in skin cancers. Cancer-associated fibroblasts (CAFs), a major tumor microenvironment (TME) component, promote cancer progression, making dual targeting of cancer cells and CAFs an effective therapy. However, dual NP-based targeting therapy on both tumor cells and CAFs is poorly investigated in skin cancers. Herein, we prepared and characterized doxorubicin-loaded PLGA NPs (DOX@PLGA NPs) and studied their anti-tumor effects on cutaneous melanoma (SKCM)(AN, M14) and cutaneous squamous cell carcinoma (cSCC) (MET1, MET2) cell lines in monolayer, as well as their impact on CAF deactivation. Then, we established 3D full thickness models (FTM) models of SKCM and cSCC using AN or MET2 cells on dermis matrix populated with CAFs respectively, and assessed the NPs' tumor penetration, tumor-killing ability, and CAF phenotype regulation through both topical administration and intradermal injection. The results show that, in monolayer, DOX@PLGA NPs inhibited cancer cell growth and induced apoptosis in a dose- and time-dependent manner, with a weaker effect on CAFs. DOX@PLGA NPs reduced CAF-marker expression and had successful anti-tumor effects in 3D skin cancer FTMs, with decreased tumor-load and invasion. DOX@PLGA NPs also showed great delivery potential in the FTMs and could be used as a platform for future functional study of NPs in skin cancers using human-derived skin equivalents. This study provides promising evidence for the potential of DOX@PLGA NPs in dual targeting therapy for SKCM and cSCC.

Improving therapeutic potential in breast cancer via histone deacetylase inhibitor loaded nanofibrils.

Epigenetic modifications play a significant role in cancer progression, making them potential targets for therapy. Histone deacetylase inhibitors have shown promise in inhibiting cancer cell growth, including in breast cancer (BC). In this research, we examined the potential of using suberoyl anilide hydroxamic acid (SAHA)-loaded β-lg nanofibrils as a drug delivery system for triple-negative BC cell lines. We assessed their impact on cell cycle progression, apoptosis, levels of reactive oxygen species, and mitochondrial membrane potential in cancer cells. The combination of SAHA and β-lg nanofibrils demonstrated enhanced efficacy in inhibiting cell growth, inducing cell cycle arrest, and promoting apoptosis (43.78%) compared to SAHA alone (40.09%). Moreover, it effectively targeted cancer cells without promoting drug resistance while using a low concentration of the nanofibrils. These findings underscore the promising potential of nanofibril-based drug delivery systems for BC treatment.

A novel pan-PI3K inhibitor KTC1101 synergizes with anti-PD-1 therapy by targeting tumor suppression and immune activation

BackgroundPhosphoinositide 3-kinases (PI3Ks) are critical regulators of diverse cellular functions and have emerged as promising targets in cancer therapy. Despite significant progress, existing PI3K inhibitors encounter various challenges such as suboptimal bioavailability, potential off-target effects, restricted therapeutic indices, and cancer-acquired resistance. Hence, novel inhibitors that overcome some of these challenges are needed. Here, we describe the characterization of KTC1101, a novel pan-PI3K inhibitor that simultaneously targets tumor cell proliferation and the tumor microenvironment. Our studies demonstrate that KTC1101 significantly increases the anti-PD-1 efficacy in multiple pre-clinical mouse models.MethodsKTC1101 was synthesized and characterized employing chemical synthesis, molecular modeling, Nuclear Magnetic Resonance (NMR), and mass spectrometry. Its target specificity was confirmed through the kinase assay, JFCR39 COMPARE analysis, and RNA-Seq analysis. Metabolic stability was verified via liver microsome and plasma assays, pharmacokinetics determined by LC–MS/MS, and safety profile established through acute toxicity assays to determine the LD50. The antiproliferative effects of KTC1101 were evaluated in a panel of cancer cell lines and further validated in diverse BALB/c nude mouse xenograft, NSG mouse xenograft and syngeneic mouse models. The KTC1101 treatment effect on the immune response was assessed through comprehensive RNA-Seq, flow cytometry, and immunohistochemistry, with molecular pathways investigated via Western blot, ELISA, and qRT-PCR.ResultsKTC1101 demonstrated strong inhibition of cancer cell growth in vitro and significantly impeded tumor progression in vivo. It effectively modulated the Tumor Microenvironment (TME), characterized by increased infiltration of CD8+ T cells and innate immune cells. An intermittent dosing regimen of KTC1101 enhanced these effects. Notably, KTC1101 synergized with anti-PD-1 therapy, significantly boosting antitumor immunity and extending survival in preclinical models.ConclusionKTC1101's dual mechanism of action—directly inhibiting tumor cell growth and dynamically enhancing the immune response— represents a significant advancement in cancer treatment strategies. These findings support incorporating KTC1101 into future oncologic regimens to improve the efficacy of immunotherapy combinations.

Role of beta-(1→3)(1→6)-D-glucan derived from yeast on natural killer (NK) cells and breast cancer cell lines in 2D and 3D cultures

BackgroundBeta-(1,3)(1,6)-D-glucan is a complex polysaccharide, which is found in the cell wall of various fungi, yeasts, bacteria, algae, barley, and oats and has immunomodulatory, anticancer and antiviral effects. In the present study, we investigated the effect of beta-(1,3)(1,6)-D-glucan derived from yeast on the proliferation of primary NK cells and breast cancer cell lines in 2D and 3D models, and on the cytotoxicity of primary NK cells against breast cancer cell lines in 2D and 3D models.MethodsIn this study, we investigated the effects of different concentrations of yeast-derived beta-(1→3)(1→6)-D-glucan on the proliferation and cytotoxicity of human NK cells and breast cancer cell lines in 2D and 3D models using the XTT cell proliferation assay and the CellTiter-Glo® 2.0 assay to determine the cytotoxicity of human NK cells on breast cancer cell lines in 2D and 3D models.ResultsWe found that the co-incubation of NK cells with beta-glucan in the absence of IL2 at 48 h significantly increased the proliferation of NK cells, whereas the co-incubation of NK cells with beta-glucan in the presence of IL2 (70 U/ml) increased the proliferation of NK cells but not significantly. Moreover, beta-glucan significantly inhibited the proliferation of breast cancer cell lines in 2D model and induced a weak, non-significant growth inhibitory effect on breast cancer multicellular tumor spheroids (3D). In addition, the cytotoxicity of NK cells against breast cancer cell lines was examined in 2D and 3D models, and beta-glucan significantly increased the cytotoxicity of NK cells against MCF-7 (in 2D).ConclusionsYeast derived beta-(1,3)(1,6)-D-glucan could contribute to the treatment of cancer by enhancing NK cell immune response as well as contributing to inhibition of breast cancer cell growth.

Antioxidant Activity, Inhibition of Intestinal Cancer Cell Growth and Polyphenolic Compounds of the Seagrass Posidonia oceanica's Extracts from Living Plants and Beach Casts.

The aim of the present study was to investigate the use of Posidonia oceanica for making products beneficial for human health. Firstly, we demonstrated that the antioxidant defense (i.e., SOD and APX activity) of P. oceanica's living leaves (LP) has low efficacy, as they partly neutralize the produced H2O2. However, high H2O2 levels led LP to produce, as a response to oxidative stress, high phenolic content, including chicoric acid, p-coumaric acid, caftaric acid, trans-cinnamic and rutin hydrate, as shown by UHPLC-DAD analysis. In addition, LP extracts inhibited intestinal cancer cell proliferation. Moreover, P. oceanica's beach casts consisting of either Wet 'Necromass' (WNP) or Dry 'Necromass' (DNP) were used for preparing extracts. Both DNP and WNP exhibited antioxidant and antiproliferative activities, although lower as compared to those of LP extracts. Although both P. oceanica's meadows and beach casts are considered priority habitats in the Mediterranean Sea due to their high ecological value, legislation framework for beach casts forbidding their removal is still missing. Our results suggested that both LP and DNP could be utilized for the production of high-added value products promoting human health, provided that a sustainability management strategy would be applied for P. oceanica's meadows and beach casts.

Cancer cells forgo translating mRNA transcribed from genes of nonspecialized tasks.

The coupling of transcription and translation enables prokaryotes to regulate mRNA stability and reduce nonfunctional transcripts. Eukaryotes evolved other means to perform these functions. Here, we quantify the disparity between gene expression and protein levels and attempt to explain its origins. We collected publicly available simultaneous measurements of gene expression, protein level, division rate, and growth inhibition of breast cancer cells under drug perturbation. We used the cell lines as entities with shared origin, different evolutionary trajectories, and cancer hallmarks to define tasks subject to specializing and trading-off. We observed varying average mRNA and protein correlation across cell lines, and it was consistently higher for the gene products in the cancer hallmarks. The enrichment of hallmark gene products signifies the resources invested in it as a task. Enrichment based on mRNA or protein abundance corresponds to the relative resources dedicated to transcription and translation. The differences in gene- and protein-based enrichment correlated with nominal division rates but not growth inhibition under drug perturbations. Comparing the range of enrichment scores of the hallmarks within each cell signifies the resources dedicated to each. Cells appear to have a wider range of enrichment in protein synthesis relative to gene transcription. The difference and range of enrichment of the hallmark genes and proteins correlated with cell division and inhibition in response to drug treatments. We posit that cancer cells may express the genes coding for seemingly nonspecialized tasks but do not translate them to the corresponding proteins. This trade-off may cost the cells under normal conditions but confer benefits during stress.

18-β-Glycyrrhetinic acid encapsulated PLGA nanoparticles attenuate lung cancer proliferation and migration

Conventional treatment methods to treat lung cancer include radiation therapy, chemotherapy, and immunotherapy. However, they cause severe adverse effects and recurrence risk. 18-β-glycyrrhetinic acid (18-β-Gly), a naturally occurring bioactive compound extracted from the liquorice plant has demonstrated anticancer potential by suppressing cancer cell growth, angiogenesis, and metastasis. Although 18-β-Gly possesses potential therapeutic abilities, the application of 18-β-Gly into clinical practices is hindered due to its inferior physicochemical characteristics such as poor bioavailability and low water solubility. Poly lactic-co-glycolic acid (PLGA) is a synthetic polymer with great tuneable options for a nano-drug delivery system used for various diseases, including cancer. Formulating 18-β-Gly into PLGA has helped to overcome challenges imposed by the poor physicochemical characteristics of 18-β-Gly. For this research, 18-β-Gly-PLGA was tested for its anticancer ability using A549 human lung adenocarcinoma lines found in lung cancer. Findings showed that 18-β-Gly-PLGA has favourable physicochemical characteristics, such as sustained in vitro drug release and good entrapment efficiency. 18-β-Gly-PLGA was also able to inhibit 15% and 50% proliferation of A549 cells at 2.5 μM and 50 μM respectively and 28% inhibition of A549 cell migration at 5 μM concentration. Oncogenes such as KRT18, EGFR, BRAF and KRAS were significantly downregulated by 43%, 19.3%, 14.7% and 13.7% respectively as part of the anticancer effects and the underlying mechanism of 18-β-Gly-PLGA. Significant reduction in the expression of cancer proliferation and migration-associated proteins such as receptor tyrosine-protein kinase ErbB2, survivin, macrophage colony-stimulating factor and mesothelin was also observed. The findings of this study demonstrate the promising potential of 18-β-Gly-PLGA as a potential anticancer agent.

Gigaxonin Suppresses Epithelial-to-Mesenchymal Transition of Human Cancer Through Downregulation of Snail.

Our results suggest that GAN gene exon 8 SNP T allele expression correlates with higher gigaxonin expression and suppression of aggressive cancer cell growth. There is downregulation of Snail and upregulation of e-cadherin through NFκB ubiquitination. We hypothesize that exon 8 T allele and gigaxonin expression could serve as diagnostic markers of suppression of aggressive growth of head and neck cancer.