Selective Killing Of Cancer Cells Research Articles

Tumor Antigens beyond the Human Exome.

With the advent of immunotherapeutics, a new era in the combat against cancer has begun. Particularly promising are neo-epitope-targeted therapies as the expression of neo-antigens is tumor-specific. In turn, this allows the selective targeting and killing of cancer cells whilst healthy cells remain largely unaffected. So far, many advances have been made in the development of treatment options which are tailored to the individual neo-epitope repertoire. The next big step is the achievement of efficacious "off-the-shelf" immunotherapies. For this, shared neo-epitopes propose an optimal target. Given the tremendous potential, a thorough understanding of the underlying mechanisms which lead to the formation of neo-antigens is of fundamental importance. Here, we review the various processes which result in the formation of neo-epitopes. Broadly, the origin of neo-epitopes can be categorized into three groups: canonical, noncanonical, and viral neo-epitopes. For the canonical neo-antigens that arise in direct consequence of somatic mutations, we summarize past and recent findings. Beyond that, our main focus is put on the discussion of noncanonical and viral neo-epitopes as we believe that targeting those provides an encouraging perspective to shape the future of cancer immunotherapeutics.

Bispecific CAR T cell therapy targeting BCMA and CD19 in relapsed/refractory multiple myeloma: a phase I/II trial

Despite the high therapeutic response achieved with B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T-cell therapy in relapsed and refractory multiple myeloma (R/R MM), primary resistance and relapse exist with single-target immunotherapy. Here, we design bispecific BC19 CAR T cells targeting BCMA/CD19 and evaluate antimyeloma activity in vitro and in vivo. Preclinical results indicate that BC19 CAR specifically recognize target antigens, and BC19 CAR T cells mediate selective killing of BCMA or CD19-positive cancer cells. BC19 CAR T cells also exhibit potent antigen-specific anti-tumor activity in xenograft mouse models. We conduct an open-label, single-arm, phase I/II study of BC19 CAR T cells in 50 patients with R/R MM (ChiCTR2000033567). The primary endpoint was safety. BC19 CAR T cells are well tolerated with grade 3 or higher cytokine release syndrome in 8% of patients and grade 1 neurotoxic events in 4% of patients, which meet the pre-specified primary endpoint. Secondary endpoints include overall response rate (92%), median progression-free survival (19.7 months), median overall survival (19.7 months) and median duration of response (not reached). Our study demonstrates that bispecific BC19 CAR T cells are feasible, safe and effective in treating patients with R/R MM.

Abstract LB199: Condensate modulator sequesters beta-catenin into depot condensates and demonstrates competitive anti-tumor activity in animal models ofcolorectal cancer

Abstract Constitutive activation of beta-catenin is a well-known driver of malignancy. However, traditional drug discovery approaches have proven challenging and largely unsuccessful in identifying therapeutic agents to modulate the function of beta-catenin. Biomolecular condensates have recently been demonstrated to play key roles in regulating most cellular processes and biological pathways by compartmentalizing biomolecules in membranelles organelles, thus lending novel opportunities to drug previously “undruggable” targets. Here, we leverage condensate biology to discover small molecules that reverse the hyperactive function of beta-catenin in colorectal cancer by entrapping it into depot condensates. We developed a high-throughput phenotypic assay that identifies beta-catenin condensate-modifying compounds (c-mods). Through condensate screening and functional secondary assays, we have identified c-mods that sequester beta-catenin into depots, induce selective cancer cell killing, and reverse oncogenic beta-catenin specific gene expression programs. C-mods identified in our screen are effective in genetically diverse colorectal cancers and a range of Wnt-associated cancers, providing the opportunity to treat a broad patient population. Furthermore, oral dosing of lead c-mod demonstrates competitive tumor growth inhibition as a single agent in xenograft and PDX models of colorectal cancer. Taken together, these results highlight the promise of condensate biology in drugging previously intractable high-value targets in oncology and developing novel treatments for patients suffering from diseases of high unmet need. Citation Format: Costa Salojin, Douglas Baumann, Adam Talbot, Kip West, Thomas Durand-Reville, Isaac Klein, Ann Boija. Condensate modulator sequesters beta-catenin into depot condensates and demonstrates competitive anti-tumor activity in animal models ofcolorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB199.

Abstract 3323: Novel Pan-RAS inhibitor ADT-007: A unique mechanism of antitumor selectivity in pancreatic and colorectal carcinoma models

Abstract Multiple types of RAS mutations activate RAS isoforms, HRAS, NRAS, or KRAS, that drive oncogenic signaling leading to uncontrolled cell proliferation and tumor development. RAS mutations occur de novo in approximately one-third of all human cancers, and are especially prevalent in pancreatic, colorectal, and lung tumors. Where RAS mutations are less frequent in other cancers, such as breast cancer, RAS can be pathologically activated by growth factor receptors that engage numerous downstream effectors. The currently FDA-approved KRAS-targeted drugs are designed to covalently inactivate only G12C KRAS mutants, however, this mutation is only prevalent in lung cancer. The most common mutations in pancreatic ductal adenocarcinoma (PDAC) are KRAS-G12D, KRAS-G12V, and KRAS-G12R. Our novel class of pan-RAS inhibitors, exemplified by ADT-007, addresses the urgent need for pan-RAS inhibitors with antitumor activity in cancers harboring these common mutations. These pan-RAS inhibitors have unique pharmacological properties that allow for selective killing of cancer cells harboring RAS mutations. ADT-007 inhibited growth of an array of carcinoma tumor cell lines in vitro with single digit nM IC50 values regardless of RAS mutant allele, and inhibited RAS activation and MAPK/AKT signaling. Because it is a pan-RAS inhibitor, ADT-007 may not be susceptible to commonly reported mechanisms of resistance to covalent KRAS inhibitors, such as activation of wild type (WT) alleles or secondary RAS mutations. Differentiated normal epithelial or hepatic cells, and tumor cells with WT RAS were insensitive to ADT-007 due to enzymatic detoxification of ADT-007 via glucuronidation, representing a novel mechanism of tumor selectivity. An orally bioavailable prodrug of ADT-007 (ADT-1004) is well tolerated in vivo, and produced sustained concentrations of ADT-007 well above IC50 values in plasma and even higher levels in tumors. Daily oral administration of ADT-1004 significantly inhibited RAS signaling and tumor growth in orthotopic and PDX mouse models of pancreatic cancer. Citation Format: Junwei Wang, Adam B. Keeton, Sindhu Ramesh, Peyton Johnson, Yulia Y. Maxuitenko, Jeremy B. Foote, Chung-Hui Huang, Kristy L. Berry, Khalda Fadlalla, Bandi D. Reddy, Ganji P. Nagaraju, Elmar Nurmemmedov, Ivan Babic, Vadim Gaponenko, Xi Chen, Bassel F. El-Rayes, Donald J. Buchsbaum, Gary A. Piazza. Novel Pan-RAS inhibitor ADT-007: A unique mechanism of antitumor selectivity in pancreatic and colorectal carcinoma models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3323.

Abstract 7243: CRISPR-cas9 genetic targeting of metastatic pancreatic cancer

Abstract Metastatic cancer affects millions of people worldwide annually and is the leading cause of cancer-related deaths. Most patients with metastatic disease are not eligible for surgical resection, and current therapeutic regimens have varying success rates, some with 5-year survival rates below 5%. Here we test the hypothesis that metastatic cancer can be genetically targeted by exploiting somatic single base substitution mutations that occur as part of normal aging prior to transformation. These passenger mutations are targetable because ~10% of them form novel tumor-specific “NGG” protospacer adjacent motif (PAM) sites targetable by CRISPR-Cas9. We studied five patients with pancreatic cancer (pc) who underwent a rapid autopsy to determine areas of evolutionary conservation that were maintained throughout all metastases in each patient’s cancer. Using whole genome sequencing validated by high-depth capture sequencing, we found that 90% of somatic PAM targets were maintained between primary carcinomas and metastases. We identified regions of loss of heterozygosity (LOH) surrounding tumor suppressor genes and oncogenes in the primary tumor where PAMs were 100% conserved in metastases. These regions of truncal LOH represent genetic vulnerabilities in these carcinomas and a CRISPR-based gene therapy approach targeting PAMs in these regions may be a novel way to genetically target metastatic cancer. Using multitarget sgRNA which cut at a known number of sites in the human genome, we determined a relationship between the number of CRISPR-Cas9 cuts and growth inhibition in PC cells. We found that 8-10 target sites in non-coding regions were sufficient to induce >95% cancer cell death. Furthermore, only 2-3 targets were required to achieve a comparable level of cell death in the presence of a DNA double strand break inhibitor. Finally, using cocultures of PC cells transduced with sgRNA targeting multiple tumor specific PAMs, we demonstrate selective cell killing of three different PC cell lines. Importantly, deep sequencing of patient-matched normal lymphocytes lacking the tumor-specific PAMs treated with the same sgRNA array exhibited no editing at the targeted loci. This work establishes a bioinformatic platform for the discovery of tumor-specific CRISPR targets in the context of metastatic disease and demonstrates selective killing of cancer cells while sparing the patient’s normal cells. These data establish the proof of principle for a gene therapy approach targeting metastatic disease. Citation Format: Kirsten Bowland, Jiaying Lai, Selina Shiqing K. Teh, Alexis Bennett, Alyza Skaist, Yan Zhang, Elizabeth Thompson, Ralph H. Hruban, Nicholas J. Roberts, Rachel Karchin, Christine A. Iacobuzio-Donahue, James R. Eshleman. CRISPR-cas9 genetic targeting of metastatic 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 7243.

Abstract 2029: Investigation of anti-tumor activity of porcine myeloperoxidase for urothelial carcinoma of the bladder

Abstract Introduction: Porcine myeloperoxidase (pMPO) is a cationic enzyme secreted by granulocytic leukocytes capable of selectively binding cancer cells due to their negative surface charge. In the presence of hydrogen peroxide (H2O2) and sodium chloride (NaCl), MPO catalyzes the production of electronically excited singlet molecular oxygen, which exerts focused cytotoxic activity against cancer cells. Methods: Human bladder non-cancer (SV-HUC1) and cancer cells (T24 and 5637) were used to assess differential cytotoxic activity of pMPO. pMPO was combined with associated reagents, including H2O2, NaCl, and L-proline and glycine for 45 minutes to support the generation of singlet oxygen. MTS assay was used to assessed cell viability at day 3 post-treatment. Non-cancer and cancer cells were labeled with GFP and mCherry, respectively, via infection with lentivirus and cultured in tandem to allow for simultaneous treatment of both cell types. After the treatment, flow cytometry and microscopy were used to monitor the growth of the cells. Results: No cytotoxicity was noted when SV-HUC1 cells were cultured with individual reagents pMPO, NaCl, L-Proline, or Glycine, and limited cytotoxicity was observed with H2O2. Notably, cell viability was nearly maximally preserved for SV-HUC1 cells. The combination of pMPO with associated reagents resulted in killing of 5637 and T24 cells, with tumoricidal activity maintained across increasing tumor cell density, with cell viability preserved for SV-HUC1 cells. Within the cell co-culture system, simultaneous treatment of both cell types with the pMPO treatment resulted in selective killing of tumor cells and preservation of SV-HUC1 cells. Mechanistic studies confirm specificity of pMPO binding to tumor cells, and further, high levels of expression of gammaH2AX and phospho-ATM in 5637 and T24 cells following treatment. Conclusion: pMPO demonstrates selective and efficient killing of bladder cancer cells with minimal cytotoxicity against non-cancer urothelial cells. Given its reliance on direct surface contact with tumor cells for activity, pMPO may be developed as an intravesical therapy for treatment of non-muscle invasive bladder cancers. Acknowledgements: This work was partially supported by Mayo funds provided to Dr. Haojie Huang. Citation Format: Junnan Liu, Robert C. Allen, Jackson T. Stephens, Paras Shah, Haojie Huang. Investigation of anti-tumor activity of porcine myeloperoxidase for urothelial carcinoma of the bladder [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 2029.

Abstract 2362: Preclinical efficacy and safety of M9140, a novel antibody-drug conjugate (ADC) with topoisomerase 1 (TOP1) inhibitor payload targeting carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5)-expressing colorectal tumors

Abstract Background: M9140 is the first clinical-stage TOP1 inhibitor payload ADC directed against CEACAM5, which is expressed in colorectal cancer (CRC) and other cancer indications. M9140 is composed of a CEACAM5-specific antibody conjugated to eight, highly stable and hydrophilic ß-glucuronide-exatecan linker-payloads. After linker cleavage, the highly potent and membrane permeable TOP1 inhibitor exatecan is released. Methods: M9140 potency was tested in viability assays using cancer cell lines with different levels of CEACAM5 expression. Potency shift viability assays were conducted using two CRC cell lines, with zosuquidar used as multidrug resistance-1 (MDR-1) inhibitor. The M9140 bystander effect was assessed in co-culture experiments with CEACAM5-negative and -positive cancer cells. Antitumor efficacy and safety were evaluated in patient-derived xenograft (PDX) mouse models and in cynomolgus monkeys, respectively. Results: M9140 demonstrated specific binding to CEACAM5 and selective killing of target-positive cancer cells with potencies between 0.09 nM and 0.62 nM. A potent bystander effect of M9140 was demonstrated in co-culture experiments indicating the potential to treat tumors with heterogeneous target expression. Unlike other ADC payloads such as monomethyl auristatin E (MMAE) and the maytansine derivative DM4, exatecan potency was not affected by MDR-1 inhibition, indicating that this drug efflux resistance mechanism may not be relevant for exatecan. A single treatment with 10 mg/kg M9140 caused strong antitumor effects in all 14 CRC PDX models tested, with tumor stasis in 10 models and tumor regression in four models as the best response. The TOP1 inhibitor-based ADC M9140 caused strong antitumor efficacy with a tumor volume reduction of 74% and 88% as best response in two CRC PDX models where a maytansine-based CEACAM5 ADC was not effective. In cynomolgus monkeys, M9140 showed dose-dependent hematolymphoid and intestinal effects, consistent with exatecan payload, with no indication of any other toxicities such as interstitial lung disease (ILD) or ocular toxicity. Conclusions: M9140 demonstrated high potency, strong antitumor activity, and bystander effect in preclinical models. The side effect profile in monkeys was favorable and in line with the expected toxicity of exatecan. Notably, ILD and ocular toxicity, which are known adverse effects of deruxtecan and maytansine-based ADCs respectively, were absent. A first-in-human study to evaluate the safety, tolerability, pharmacokinetics, and preliminary clinical activity of M9140 in advanced solid tumors is ongoing (NCT05464030). Citation Format: Sabine Raab-Westphal, Felix Hart, Willem Sloot, Min Shan, Nicolas Rasche, Christiane Amendt, Jan Anderl. Preclinical efficacy and safety of M9140, a novel antibody-drug conjugate (ADC) with topoisomerase 1 (TOP1) inhibitor payload targeting carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5)-expressing colorectal tumors [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 2362.

Carboxymethyl-sagocellulose-stabilized Fe3O4 nanoparticles with 5-fluorouracil as photothermal agents for tumor ablation

BackgroundThere is a continuous growth of interest in the development of nano-drug delivery systems that could combine therapy and diagnosis of cancer.ResultsNovel multifunctional superparamagnetic iron oxide nanoparticles (SPIONs, chemically Fe3O4) conjugated with carboxymethyl sagocellulose (CMSC), and 5-fluorouracil (Fe3O4-CMSC-5FU) were synthesized. The conjugated nanoparticles have the magnetic properties of the SPIONs, which allows the nanoparticles to be localized at the target area by applying an external magnetic field. SPIONs generate heat upon exposure to laser lights, resulting in a photothermic effect. The drug-loading efficiency of 5-FU into the SPIONs-CMSC conjugated nanoparticles was 70 to 84% w/w which could release the drug at intracellular pH (5.4) of cancer cells and resist drug release at pH 7.2. In vivo studies using mice models confirmed the nanoparticles could efficiently deliver 5-FU only to the cancer cells and the anticancer effect was enhanced by laser-induced hyperthermia.ConclusionsThe combination of targeted delivery of 5-FU with photothermal therapy (PTT) looks promising for selective killing of cancer cells. Furthermore, SPIONs are an excellent contrasting agent for use in computerized tomography (CT) imaging for determining the tumor location and monitoring the progress of the therapy. The focus of this work was the oncological application of multifunctional Fe3O4-CMSC-5FU nanoparticle conjugates, with an emphasis on therapeutic, diagnostic and prognostic purposes.

γ-glutamyl transpeptidase activatable NIR photosensitizer for visualization and selective killing of liver cancer cells

Photodynamic therapy (PDT) is a treatment model that involves using light sources to excite photosensitizers (PSs), generating reactive oxygen species. This method is considered a potential treatment for tumors. However, the non-selective toxicity of traditional PSs to both tumors and normal tissues hinders the advancement of PDT. This lack of selectivity is a major obstacle in the development of effective PDT. The activatable PS can only function in a specific environment, which enhances the selectivity and safety of PDT. In this paper, we focus on GGT (γ-glutamyltranspeptidase) overexpressed in liver cancer as the biological target. We designed and synthesized the activatable PS BrCy-Glu by modifying the substrate of GGT (l-glutamic acid) onto the brominated hemicyanine PS (BrCy-OH). The intramolecular charge transfer (ICT) effect of BrCy-Glu is inhibited, which leads to low fluorescence quantum yield and singlet oxygen yield. However, in the presence of GGT, it can undergo selective hydrolysis and be converted into BrCy-OH through a series of elimination reactions. This process is accompanied by a significant increase in fluorescence quantum yield and singlet oxygen yield. In vitro studies demonstrate that BrCy-Glu is suitable for precise fluorescence identification of liver cancer and selective eradication of cancer cells under light conditions.

NQO-1 activatable NIR photosensitizer for visualization and selective killing of breast cancer cells

The diagnosis and treatment of breast cancer is of immense importance in improving patient outcomes. The biological marker NAD(P)H:quinone oxidoreductase 1 was utilized to design BrCyS-Q, a near-infrared activatable photosensitizer for breast cancer. BrCyS-Q was successfully employed to diagnose breast cancer cells using fluorescence and photodynamic inhibition. The findings of this research may offer novel insights for the diagnosis and treatment of clinical breast cancer via photodynamic therapy.

Abstract C128: PT-112, a novel immunogenic cell death inducer, causes ribosomal biogenesis inhibition and organelle stress in cancer cells

Abstract PT-112 is a novel immunogenic small molecule under Phase 2 development in metastatic castration-resistant prostate cancer and thoracic malignancies. PT-112 has been shown to release damage-associated molecular patterns, essential immune signaling components of immunogenic cell death (ICD), and to elicit anticancer immune responses. In addition, PT-112 causes mitochondrial and endoplasmic reticulum (ER) stress in vitro. Here, we sought to elucidate early molecular effects of PT-112 that culminate in cancer cell death. We assessed nucleolar protein phenotypes in human prostate cancer cells treated with PT-112 using antibody labeling, followed by confocal microscopy. We also conducted nascent RNA sequencing in human cancer cells (non-small cell lung, prostate, and renal cell carcinoma) following 1- and 6-hour PT-112 treatment. We then performed an analysis using Enrichr across multiple databases to identify biological pathways linked to clusters of differentially expressed genes (p ≤ 0.001) in PT-112-treated cells. Pathways affected by PT-112 (p ≤ 0.05) were sorted by statistical significance.  In prostate cancer cells, PT-112 caused changes in nucleolar protein labeling. The most pronounced effect, observed after 8 or more hours of treatment, was rapid NPM1 relocation from nucleoli to nucleoplasm, a hallmark of nucleolar stress and disruption of ribosomal biogenesis (RiBi). PT-112 also induced gene expression changes in the treated cancer cell lines, resulting in statistically significant repression of pathways related to RiBi, ribosomal RNA (rRNA) processing and translation. Notably, a pattern across these pathways was the reduced expression of many ribosomal genes, consistent with RiBi inhibition. Additional analysis identified oncogenic pathways such as Myc and NF-κB significantly inhibited by PT-112. The degree of pathway suppression increased with treatment time. These results demonstrate that PT-112 rapidly causes nucleolar stress and RiBi inhibition, suggesting these are central to PT-112-induced cancer cell death. This mechanism could also explain the selective killing of cancer cells by PT-112, given that aberrant nucleolar size and number as well as ribosomal activity in cancer cells make them more sensitive to these drug effects. The broad consequences of impaired ribosome production and downstream protein translation may explain PT-112’s anticancer and immunogenic effects. Additionally, these disruptions have been reported to cause an increase in free ribosomal proteins and changes in nucleolar protein localization, which have been shown to induce ER stress and shuttle pro-apoptotic proteins to the mitochondria. These additional consequences of RiBi inhibition and nucleolar stress may contribute to or drive previously observed PT-112-induced cancer organelle stress and ICD. While further validation of these findings is needed, this work deepens our understanding of PT-112’s mechanism of action. Present findings, together with demonstrated clinical activity of PT-112, position it as a promising small molecule cancer immunotherapy. Citation Format: Christina Y. Yim, Maria T. Congenie, Hannah L. Johnson, Maureen G. Mancini, Fabio Stossi, Michael A. Mancini, Joey Azofeifa, Matthew R. Price, Johan Baeck, Tyler D. Ames. PT-112, a novel immunogenic cell death inducer, causes ribosomal biogenesis inhibition and organelle stress in cancer cells [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr C128.

Abstract B109: MTHFD1/2 inhibitor TH9619 targets the DNA damage response and causes cancer-specific folate trapping with an unprecedented therapeutic window

Abstract The MTHFD2 protein is consistently the most overexpressed enzyme when comparing cancer and normal cells and tissue. The protein regulates formate release from mitochondria and generation of nucleotides required for rapid cell growth. An additional role of MTHFD2 in DNA repair and genomic stability in cancer cells is also emerging. The MTHFD2 has been validated genetically as an anti-cancer target by numerous laboratories, but the enzyme has been notoriously difficult to target. Here, we describe first-in-class nanomolar MTHFD2 inhibitors, with protein co-crystal structures demonstrating binding in the active site of MTHFD2 and engaging with the target in cells and tumours. Because of the structural resemblance between MTHFD1, all MTHFD2 inhibitors were also found to inhibit MTHFD1, but no other folate-binding protein, kinases or other proteins. Here, we report that MTHFD1/2 inhibitors (MTHFD1/2i) reduce replication fork speed and induce replication stress, followed by S phase arrest, apoptosis and efficient killing of cancer cells in vitro and in vivo. Mechanistically, we find MTHFD1/2i prevent thymidine production leading to the misincorporation of uracil into DNA and replication stress. We show that TH9619 targets the nuclear MTHFD2 but not mitochondrial MTHFD2. Because of this, MTHFD1/2i lead to a unique folate trap, accumulation of 10-formyl-tetrahydrofolate, which depletes cells of tetrahydrofolate leading to thymidylate depletion and selective killing of MTHFD2-expressing cancer cells. Importantly, the folate trap is not generated in non-transformed cells that do not express MTHFD2. We also show that MTHFD1/2i target the DNA damage response (DDR), and the combined effect of targeting the DDR and generating a cancer-specific folate trap explains the unique > 1000-fold therapeutic index generated by these inhibitors. Furthermore, we show efficient haematological and solid cancer targeting in vitro and in vivo. Excitingly, we find potent anti-cancer efficacy and complete responses at low doses in vivo while demonstrating tolerability at 1000x fold higher doses, altogether underscoring the novelty of our approach. In conclusion, MTHFD1/2 inhibitors will offer a major new DDR inhibitor attack on cancer soon to be tested in clinical trials Citation Format: Petra Martilla, Alanna C Green, Nicole Kiweler, Christina Chalkiadaki, Elisée Wiita, Victoria Cookson, Antoine Lesur, Kim Eiden, François Bernhardin, Maeve Long, Ann-Sofie Jemth, Oliver Mortusewicz, Evert Homan, Nadilly Bonagas, Louise Ramos, Kumar Sanjiv, Emilio Guillén Mancina, Therese Pham, Ana Slipicevic, Martin Henriksson, Johannes Meiser, Thomas Helleday. MTHFD1/2 inhibitor TH9619 targets the DNA damage response and causes cancer-specific folate trapping with an unprecedented therapeutic window [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B109.

Lectin-anticancer peptide fusion demonstrates a significant cancer-cell-selective cytotoxic effect and inspires the production of "clickable" anticancer peptide in Escherichia coli.

Targeted killing of tumor cells while protecting healthy cells is the pressing priority in cancer treatment. Lectins that target a specific glycan marker abundant in cancer cells can be valuable new tools for selective cancer cell killing. The lectin Shiga-like toxin 1 B subunit (Stx1B) is an example that specifically binds globotriaosylceramide (CD77 or Gb3), which is overexpressed in certain cancers. In this study, a human lactoferricin-derived synthetic retro di-peptide R-DIM-P-LF11-215 with antitumor efficacy was fused to the lectin Stx1B to selectively target and kill Gb3+ cancer cells. We produced lectin-peptide fusion proteins in Escherichia coli, isolated them by Gb3-affinity chromatography, and assessed their ability to selectively kill Gb3+ cancer cells in a Calcein AM assay. Furthermore, to expand the applications of R-DIM-P-LF11-215 in developing therapeutic bioconjugates, we labeled R-DIM-P-LF11-215 with the unique reactive non-canonical amino acid Nε -((2-azidoethoxy)carbonyl)-L-lysine (AzK) at a selected position by amber stop codon suppression. The R-DIM-P-LF11-215 20AzK and the unlabeled R-DIM-P-LF11-215 parent peptide were produced as GST-fusion proteins for soluble expression in E. coli for the first time. We purified both variants by size-exclusion chromatography and analyzed their peptide masses. Finally, a cyanin 3 fluorophore was covalently conjugated to R-DIM-P-LF11-215 20AzK by strain-promoted alkyne-azide cycloaddition. Our results showed that the recombinant lectin-peptide fusion R-DIM-P-LF11-215-Stx1B killed >99% Gb3+ HeLa cells while Gb3-negative cells were unaffected. The peptides R-DIM-P-LF11-215 and R-DIM-P-LF11-215 20AzK were produced recombinantly in E. coli in satisfactory amounts and were tested functional by cytotoxicity and cell-binding assays, respectively.

Advances in Polatuzumab Vedotin-PIIQ Therapy: A Review of Treatment Efficacy in Diffuse Large B Cell Lymphoma and High-Grade B Cell Lymphoma.

Polatuzumab vedotin (PV) is an antibody-drug conjugate that has shown promising results in the treatment of diffuse B-cell lymphoma (DLBCL) and high-grade B-cell lymphoma (HGBCL). This abstract summarizes the current understanding of PV's use in these malignancies based on available clinical data. Multiple clinical trials have evaluated PV as a part of combination therapy regimens in relapsed/refractory DLBCL and HGBCL. The pivotal Phase II study, GO29365, demonstrated that PV in combination with bendamustine and rituximab (BR) significantly improved progression-free survival and overall survival compared to BR alone in patients with relapsed/refractory DLBCL who ineligible for stem cell transplantation were. Subsequently, the US Food and Drug Administration granted accelerated approval to PV in this setting. PV's mechanism of action involves targeting CD79b, a cell surface receptor expressed in B-cell malignancies, and delivering the cytotoxic agent monomethyl auristatin E to CD79b-expressing cells. This approach enhances the selective killing of cancer cells while sparing normal cells. The safety profile of PV is generally manageable, with adverse events including infusion-related reactions, cytopenia, peripheral neuropathy, and infections. Overall, PV has emerged as a valuable treatment option for patients with relapsed/refractory DLBCL and HGBCL, offering improved outcomes when combined with appropriate chemotherapy regimens. Ongoing research and clinical trials are further exploring PV's potential in various treatment settings, including frontline therapy and in combination with other novel agents.

Albumin Nanoparticles Surface Decorated with a Tumor-Homing Peptide Help in Selective Killing of Triple-Negative Breast Cancer Cells.

In this article, we describe a method of delivery of doxorubicin using a novel tumor-homing peptide-based albumin nanoparticle system to triple-negative breast cancer cells (TNBC). The absence and reduced expression of the hormone (estrogen, progesterone) and HER2 (human epidermal growth factor 2) receptors, respectively, render TNBC patients nonsusceptible to different available targeted therapies. These peptide-modified nanoparticles could be taken up by TNBC cells more effectively than their bare counterparts. The drug-loaded peptide-modified nanoparticles achieved an optimal but crucial balance between cell killing in cancerous cells and cell survival in the noncancerous ones. This appears to be because of different routes of entry and subsequent fate of the bare and peptide-modified nanoparticles in cancerous and noncancerous cells. In a TNBC mouse model, the peptide-modified system fared better than the free drug in mounting an antitumor response while not being toxic systemically.

A novel fluorescent dye selectively images and kills cancer stem cells by targeting mitochondria: Evidence from a cell line‑based zebrafish xenograft model.

Numerous agents such as near-infrared dyes that are characterized by specialized cancer imaging and cytotoxicity effects have key roles in cancer diagnosis and therapy via molecularly targeting special biological tissues, organelles and processes. In the present study, a novel fluorescent compound was demonstrated to inhibit cancer cell proliferation in a zebrafish model with slight in vivo toxicity. Further studies demonstrated selective staining of cancer cells and even putative cancer stem cells via accumulation of the dye in the mitochondria of cancer cells, compared with normal cells. Moreover, this compound was also used to image cancer cells in vivo using a zebrafish model. The compound displayed no apparent toxicity to the host animal. Overall, the data indicated that this compound was worthy of further evaluation due to its low toxicity and selective cancer cell imaging and killing effects. It could be a useful tool in cancer research.

Reconstituting Low-Density Lipoprotein with NIR-Absorbing Organic Photothermal Agents for Targeted Killing of Cancer Cells.

Photothermal therapy (PTT) systems typically do not possess intrinsic tumor-targeting capability, resulting in indiscriminate thermal damage to both cancer and normal cells. Herein, a low-density lipoprotein (LDL)-based nanosystem (denoted as MTTQ@LDL) is reported for targeted photothermal killing of cancer cells. Such a nanosystem is fabricated by reconstituting the lipophilic core of LDL with an organic photothermal agent MTTQ. The reconstitution process improves the supramolecular photothermal effects of MTTQ assemblies, which contributes to the significantly enhanced photothermal conversion efficiency (41.3%vs. 16.2%). MTTQ@LDL can actively target LDL receptor-overexpressed cancer cells via receptor-mediated endocytosis, enabling the selective killing of cancer cells over normal cells (98%vs. 7%) post-NIR irradiation. Reconstituted LDL can serve as a promising platform for targeted delivery of functional materials, holding great promise in tumor eradication in vivo.

Alum-tuned hyaluronic acid-based hydrogel with immune checkpoint inhibition for immunophoto therapy of cancer

Alum-crosslinked hyaluronic acid-dopamine (HD) hydrogel containing indocyanine green (ICG) with anti-programmed cell death-1 (PD-1) antibody (Ab) administration was developed for immunophoto therapy of cancer. Alum modulates the rheological characteristics of hydrogel for enabling syringe injection, shear-thinning feature, and slower biodegradation. In addition, alum in HD-based hydrogel provided CD8+ T cell-mediated immune responses for cancer therapy. ICG in the hydrogel under near-infrared (NIR) light exposure may induce hyperthermia and generate singlet oxygen for selective cancer cell killing. HD/alum/ICG hydrogel injection with NIR laser irradiation elevated PD-1 level in CD8+ T cells. Administration of PD-1 Ab aiming at highly expressed PD-1 in T cells may amplify the anticancer efficacies of HD/alum/ICG hydrogel along with NIR laser. HD/alum/ICG hydrogel with NIR light may have both CD8+ T cell-linked immune responses and ICG-related photodynamic/photothermal effects. Additional injection of immune checkpoint inhibitor can ultimately suppress primary and distant tumor growth by combination with those therapeutic actions.

Micromagnetic Approach to the Metastability of a Magnetite Nanoparticle and Specific Loss Power as Function of the Easy-Axis Orientation

Magnetic nanoparticles (MNPs) have attracted a great interest in nanomedical research. MNPs exhibit many important properties. In particular, magnetic hyperthermia for selective killing of cancer cells is one of them. In hyperthermia treatment, MNPs act as nano-heaters when they are under the influence of an alternating magnetic field (AMF). In this work, micromagnetic simulations have been used to investigate the magnetization dynamics of a single-domain nanoparticle of magnetite in an external AMF. Special attention is paid to the circumstances dealing with a dynamic phase transition (DPT). Moreover, we focus on the influence of the orientation of the magnetic easy-axis of the MNP on the dynamic magnetic properties. For amplitudes of the external AMF above a certain critical value, the system is not able to follow the magnetic field and it is found in a dynamically ordered phase, whereas for larger amplitudes, the state corresponds to a dynamically disordered phase and the magnetization follows the external AMF. Our results suggest that the way the order-disorder DPT takes place and both the metastable lifetime as well as the specific loss power (SLP) are strongly dependent on the interplay between the orientation of the magnetic easy-axis and the amplitude of the external AMF.

Synergistic Effect of Simultaneous Testosterone Reduction and Selective Killing of Prostate Cancer Cells with Oral Bioavailable Curcumin Capsules May Ensure a Significant Drop in PSA Levels from Abnormally High Levels Due to Confirmed Metastasized Prostate Cancer

In this century there have been 1000s of Pubmed listed publications making multiple claims about the potential health benefits of curcumin found in the curry spice, turmeric. A baby boomer male who was diagnosed with benign prostate hyperplasia (BPH), later after difficulty in urination, constriction of Urethra was treated with urethral catheterization. A year after BPH diagnosis, the PSA rose to 64 ng/ml and bone biopsy revealed prostate cancer cells, at which time a simultaneous combination treatment of Lupron depot and turmeric capsules from a pharmacy, containing curcumin was administered. 6 months after the combination treatment, the PSA level have remained well below average normal, around 0.3 ng/ml and the urination difficulties were resolved. While the noninvasive treatment without surgical removal of the prostate gland, has worked quite exceptionally for the time being, this report and review should be of broad interest for those who are involved in timely care of patients with enlarged prostate due to BPH, prostatitis, prostate cancer, and metastasized prostate cancer.