Anticancer Research Articles

CD40 agonist on patient-derived xenograft mice for the treatment of B-cell acute lymphoblastic leukemia

Abstract Purpose: Cluster of differentiation 40 (CD40) is expressed on B-cell acute lymphoblastic leukemia (B-ALL) cases. However, the effect of CD40 activation on B-ALL cells has never been tested in vivo. Experimental Design: The aim of our preclinical study was to investigate the therapeutic potential of a CD40 agonist in the treatment of B-ALL using patient-derived xenograft (PDX) mouse models. Results: Intravenous administration of the CD40 agonist significantly impeded B-ALL cell proliferation and growth in vivo, accompanied by rapid activation of the extracellular signal-regulated kinase (ERK) pathway, leading to the induction of apoptosis and disruption of cell cycle progression. Co-treatment with a specific inhibitor of ERK further demonstrated that CD40 stimulation induced the pro-apoptosis of B-ALL cells in an ERK-dependent manner. Proteomic analysis revealed alterations in key signaling pathways associated with B-ALL expansion and maintenance. Moreover, the CD40 agonist markedly reduced the frequency of leukemia-initiating cells and leukemia development in PDX mice. Our study showed that the CD40 agonist can be associated with chemotherapeutic agents such as vincristine and dexamethasone, and this combination showed improved effectiveness. Additionally, the CD40 agonist was more effective on pre-B-ALL (EGIL B-III) that expressed CD40, than on common B-ALL (EGIL B-II) that lacked CD40 expression. Conclusion: These findings suggest that CD40 agonists are promising immunotherapeutic candidates for pediatric B-ALL, warranting further clinical investigations to improve patient outcomes in CD40-expressing B-ALL.

The Effectiveness of Steroids and Antioxidants in the Management of Cisplatin-induced Ototoxicity: A Comprehensive Systematic Review of the Literature and Network Meta-Analysis

Abstract Background: Cisplatin efficacy in cancer therapy is hindered by dose-dependent toxicities, including ototoxicity. Its mechanisms involve cochlear damage and oxidative stress. Gender and age affect susceptibility, with limited treatment options for adults. Objective: To assess the effectiveness of steroids compared to antioxidants (AOs) in preventing and managing cisplatin-induced ototoxicity. Materials and Methods: Data were collected from multiple sources including Medline, CENTRAL, PubMed, and Springer Nature Journals. Adults and pediatrics with the clinical diagnosis of cisplatin-induced ototoxicity, interventional studies (including single-arm studies) were included. Studies with a focus on chemotherapy agents other than cisplatin were excluded. Results: The study encompassed 10 randomized controlled trials spanning 2004–2023 across Canada, Israel, The Netherland, Spain, Turkey, Greece, Italy, and Iran. It aimed to evaluate interventions for preventing cisplatin-induced ototoxicity, including intratympanic injections and oral dietary supplements. Based on the results of this systematic review, thiosulfate-hyaluronate gel showed a 1.3 dB reduction in hearing loss; dexamethasone injections had minimal efficacy; L-N-acetylcysteine (L-NAC) offered significant otoprotection with daily infusion; and transtympanic L-NAC showed no significant benefit. Salicylate usage yielded no decrease in hearing loss. AO dietary supplements showed no difference in results between groups. However, based on the network meta-analysis results, it appears that steroids perform best in reducing cisplatin-induced ototoxicity at higher frequencies (8000 Hz), followed by placebo and then AO. Conclusion: A further molecular and targeted therapy is needed to target the cyto/ototoxic activity and further prevent such deterioration in hearing and promote chemotherapy regime without ototoxic effects.

Abstract A024: Assessing Mitondiral Priming in Leukemia Using BH3 Complex Specific Antibodies (PRIMABS): Prediciting Patient Response to Apoptosis Inducing Drugs

Abstract Diagnostic tools for cancer therapy that enable oncologists to inform patients about the likely benefits of their treatment versus toxicity will empower patients to make evidence-based decisions about the management of their disease, and in some cases, their last phase of life. Here we provide a novel approach that measures key drug response features of individual cancer cells with the potential for providing prognostic/predictive diagnostic utility for practicing precision medicine. Most cancer treatments work though activation of the cell suicide program of apoptosis. This process is tightly regulated by the BCL-2 family of proteins whose members either prevent or promote cell death. The relative levels of, and the specific interactions between the pro-survival and pro-apoptotic family members that dictates the fate of all cells and determines their propensity to undergo apoptosis. Cells that more readily die in response to various stimuli are referred to as “primed”. Hence, the degree of priming of a tumor sample can be predictive of responses to anti-cancer drugs and can be established using a technique called “BH3 profiling”. The relevance of this method has been demonstrated but it has had only limited application. To address this limitation a unique panel of antibody-based reagents that are mitochondrial PRIMing state detecting Antibodies (PRIMABS), have been developed by our lab, as a novel approach to implementing personalized medicine and developing predicative diagnostic tests. These antibodies enable the degree of tumor cell priming to be determined directly, unlike BH3 profiling which is an indirect measure. The key innovation lies in the approach taken to determine the presence (or absence) of the critical pro-survival : pro-apoptotic protein complexes , as these are the principal determinants of cell priming.. Such PRIMAB reagents have hitherto not been available. Here we provide data outlining the methodology development as well as evidence demonstrating feasibility of PRIMABTM Dx platform for predicting AML and CLL patient response in retrospective studies. Our platform provides a PD biomarker that will become a clinical predictor of cancer cell response to treatments tat are intended to induce apopstosis in tumor cells. The PRIMABTM -DX platform will enable heretofore hard to achieve clinical applicability of priming measurements. This will be significant due to the important prognostic implications of PRIMAB-DxTM readouts and will provide insights into drug resistance and sensitivity mechanisms and lead to new treatment options for cancer patients. Citation Format: Michael Cardone. Assessing Mitondiral Priming in Leukemia Using BH3 Complex Specific Antibodies (PRIMABS): Prediciting Patient Response to Apoptosis Inducing Drugs [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr A024.

Abstract PR004: Second generation RNA Polymerase I inhibitor PMR-116 targets ribsomal RNA synthesis to potently treat a broad spectrum of malignancies

Abstract Purpose and rational for the study: The purpose of the study was to develop novel 2nd generation ribosomal RNA synthesis inhibitors for cancer treatment. Ribosome biogenesis (RiBi) is essential for cell growth and proliferation. Transcription of ribosomal RNA genes by Pol I is a critical step in RiBi and is tightly regulated by tumor suppressors and oncoproteins. Indeed, the ability of the potent oncoprotein, MYC, to drive RiBi is necessary for its oncogenic activity (Bywater et al., Cancer Cell, 2011). These data suggested that targeting RiBi, might be a promising strategy to treat malignancies, especially those driven by MYC. To test this, we developed the 1st small molecule inhibitor of Pol I transcription, CX-5461 (Drgyin et al., Cancer Research 2011). While CX-5461 has shown promising activity in pre-clinical studies (Bywater et al., Cancer Cell, 2011; Rebello et al., Clin Cancer Res., 2016; Hein et al., Blood, 2017) and in early Phase trials (Khot et al., Cancer Discovery, 2019; Hilton et al., Nat Commun. 2022) its mechanism of action remains controversial with evidence of off-target activity inducing DNA damage through inhibition of TOPO2a (Cameron et al., Biomedicines, 2024; Koh et al., Nature Genetics, 2024). Thus, to determine if selective inhibition of Pol I transcription in the absence of DNA damage can be used to therapeutical treat cancer in vivo, we developed a series of more selective 2nd generation Pol I inhibitors with our lead compound being PMR-116. Methods and summary of data: We demonstrate that PMR-116 is selective for inhibition of Pol I over Poll II transcription and functions by stalling the Pol I complex at the rDNA promoter. PMR-116, exhibits improved drug-like properties and pharmacokinetics compared to 1st generation CX-5461. As a single agent PMR-116 efficiently treats a range of pre-clinical models of hematologic and solid tumors including lymphoma, AML, hepatocellular carcinoma and prostate cancer. MYC expression positively correlates with sensitivity to PMR-116 in human cancer cell lines and high MYC tumors in vivo are exceptionally sensitive to PMR-116. In contrast to CX-5461, the therapeutic response to PMR-116 occurs in the absence of DNA damage suggesting that DNA damage is not an obligatory response to Pol I transcription inhibition but rather an off-target effect of the 1st generation drug. Small molecule drug combination screens in AML cells demonstrate that PMR-116 works synergistically to reduce cell viability with a range of drugs including carfilzomib and quisinostat used for treatment of hematologic malignancies. Conclusions: Our data establishes inhibition of RNA polymerase I as a bone fide therapeutic target for cancer therapy and demonstrated that PMR-116 is a promising new broad- spectrum anti-cancer drug particularly for those tumors driven by MYC, which are highly refractory to standard therapies. Based on these data we have launched a Phase I clinical trial of PMR-116 in patients with advanced solid tumors (CTRN12620001146987). Citation Format: Rita Ferreira, Katherine M. Hannan, Konstantin Panov, Thejanni Udumanne, Amee J George, Zaka Yuen, Perlita Poh, Eric Kusnadi, Alisee Huglo, Mitchell Lawrence, Mustapha Haddach, Denis Drygin, Luc Furic, Ross D Hannan, Nadine Hein. Second generation RNA Polymerase I inhibitor PMR-116 targets ribsomal RNA synthesis to potently treat a broad spectrum of malignancies [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr PR004.

Abstract I005: Exploiting the immunoregulatory effect of double-stranded RNAs for cancer therapeutics

Abstract Introns are found in all eukaryotes and are one of the defining characteristics of eukaryotes. After transcription, pre-mRNAs undergo splicing, and introns are excised in the lariat structure. Since excised introns are degraded quickly after debranching, they have been considered as byproducts of gene expression, and their post-splicing role in the cells remains unclear. Here, we find that the inhibition of intron debranching process by depleting a debranching enzyme, DBR1, results in hyperactivation of protein kinase R (PKR) due to accumulation of intron lariat-derived transposable elements (TEs) that can adopt double-stranded secondary structure. Through in vitro PKR-binding assay, we show that PKR strongly binds to intron lariat RNAs harboring TEs, especially inverted Alu repeats. Interestingly, these TE-containing lariat RNAs are retained in the nucleus, but are released to the cytosol during mitosis, where they activate PKR, resulting in aberrant mitotic progression and apoptosis. We further exploit the lariat RNA-PKR interaction during mitosis and show that DBR1 depletion and anti-mitotic chemotherapy drugs can synergistically induce cancer cell death both in vitro and in vivo. Lastly, we perform docking simulation-based screening of DBR1-inhibitory small molecules. Collectively, our findings underscore the significance of intron turnover in avoiding innate immune activation and further suggest a potential strategy to enhance the efficacy of anti-mitotic drugs by targeting intron processing. Citation Format: Keonyong Lee, Jayoung Ku, Tria Asri Widowati, Namwook Kim, Soo Young Park, Han Suk Ryu,Yoosik Kim. Exploiting the immunoregulatory effect of double-stranded RNAs for cancer therapeutics [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr I005.

Abstract B016: RNA demethylase ALKBH5 drives medulloblastoma growth and progression

Abstract Introduction: Medulloblastoma (MB) is the most common malignant childhood brain tumor. It accounts for 20% of all childhood cancer deaths. MB are very fast-growing tumors, which spreads to central nervous system through cerebrospinal fluid, leading to leptomeningeal metastases that occurs up to 66% in brain cancer patients. Despite the progress in treating MB, the 5-year survival rate for high-risk MB remains poor with high recurrence. Moreover, the quality of life for those kids who do survive is substantially reduced due to the high toxicity associated with the high radiation exposure and multiple drug chemotherapy they must endure at such an early age. Therefore, it is critical to identify novel factors and understand previously undefined mechanisms that drive MB growth and progression, so that safe and viable therapeutics can be developed for treating MB. In this study, we tested the hypothesis that epigenetic changes, specifically mRNA demethylation mediated by the RNA demethylase ALKBH5, play an important role in MB growth and tumor progression, and hence approaches aimed at inhibiting ALKBH5 activity could prove clinical utility for MB patients. Methods: Medulloblastoma cell lines (HD-MB03, D556, D425 and DAOY) were purchased from the ATCC. MB cancer stem cells (MB-CSC) were stained Aldefluor sorted by Flow cytometry and cultured in stem cell medium. MB cells were transfected either with ALKBH5 overexpression (OE) plasmid or siRNA (KD). These OE/KD MB cells were analyzed for cell viability, migration, invasion, colony formation, cell cycle, apoptosis assays, RNA sequencing, RT-qPCR, western blotting, RNA immunoprecipitation, and in vivo tumor xenograft study. Results: Our results revealed that MB cells are highly dependent on ALKBH5 for their survival. Using multiple MB cell lines with or without ALKBH5 depletion, we discovered that of ALKBH5 inhibited both short and long-term growth of MB cells. In addition, knockdown of ALKBH5 inhibited the migration of MB cells. ALKBH5 silenced MB cells showed increased apoptosis. Importantly, we show that ALKBH5 silencing suppressed the self-renewal/proliferation of MB stem cells (including medullosphere formation). ALKBH5 knockdown HDMB03-GFP-luciferase cells injected into mouse showed reduced tumor growth compared to the control. RNA sequencing analysis of ALKBH5 depleted MB cells showed alterations in several metabolism related pathways. Further, ALKBH5-depletion led to significantly decreased levels of cancer stem cell marker proteins including Nanog, OCT4 and SOX9. These are significant findings as MB stem cells are considered to be the major source of MB initiation, maintenance, relapse and render MB cells resistant to radiation. Conclusion: Collectively, our study results suggest that RNA demethylase ALKBH5 may play an important role in MB growth and progression by supporting MB cancer (tumor initiating) stem cells (MB-CSC) and ALKBH5 serves as a novel therapeutic target for MB. Citation Format: Panneerdoss Subbarayalu, Daisy Medina, Pitta Prabhakar, Shahad Abdulsahib, Saif Nirzhor, Desiree Denman, Santosh Timilsina, Deepika Singh, Phat Do, Krishna Evani, Dhiya Billa, Esha Reddy, Peter Houghton, Yogesh Gupta, Yidong Chen, Suryavathi Viswanadhapalli, Ratna Vadlamudi, Andrew Brenner, Manjeet Rao. RNA demethylase ALKBH5 drives medulloblastoma growth and progression [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr B016.

Progress in the study of toxic effects of drugs on the male reproductive system

This paper provides a comprehensive summary of the toxic effects of drugs on the male reproductive system, with a special focus on the mechanisms of testicular and sperm damage caused by chemotherapeutic agents, antibiotics, and immunosuppressants. Drug-induced reproductive toxicity usually manifests through multiple pathways including direct injury, interference with hormone regulation, oxidative stress, and DNA damage. These mechanisms can lead to impaired spermatogenesis, decreased testicular function, and long-term infertility, thereby seriously affecting male reproductive health. Specifically, chemotherapeutic drugs, such as cisplatin and cyclophosphamide, have been widely documented to cause direct damage to the testes, leading to significant decreases in sperm quantity and quality. Antibiotics and nonsteroidal anti-inflammatory drugs also negatively affect reproductive function by affecting mitochondrial function and inducing oxidative stress in the testicular cells. Although important advances have been made in recent years in the study of drug-induced reproductive toxicity, further exploration is needed to assess the variability of individual responses to drugs and develop long-term protective measures. Future research should focus on developing accurate toxicity assessment methods, customized therapeutic regimens, and enhanced fertility protection strategies, such as the use of antioxidants and methods for the cryopreservation of testes and sperm. Interdisciplinary collaboration will provide new solutions for balancing disease treatment and fertility preservation, especially in the use of high-risk drugs, such as anticancer therapies, where achieving both efficacy and reproductive health will be an important clinical challenge.

Microfluidic Fabrication of Oleosin-Coated Liposomes as Anticancer Drug Carriers with Enhanced Sustained Drug Release

Microfluid-derived liposomes (M-Lipo) exhibit great potential as drug and functional substance carriers in pharmaceutical and food science. However, the low liposome membrane stability, attributed to the liquid core, limits their application range. Oleosin, a natural surfactant protein, can improve the stability of the lipid nanoparticle membrane against various environmental stresses, such as heat, drying, and pH change; in addition, it can enable sustained drug release. Here, we proposed the fabrication of oleosin-coated M-Lipo (OM-Lipo) through self-assembly on a microfluidic chip and the evaluation of its anticancer drug (carmustine) delivery efficiency. Nanoparticle characterization revealed that the oleosin coating slightly lowered the membrane potential of M-Lipo and greatly improved their dispersibility. Additionally, the in vitro drug release profile showed that the oleosin coating improved the sustained release of the hydrophobic drug from the phospholipid bilayer in body temperature. Our results suggest that OM-Lipo has sufficient potential in various fields, based on its easy production, excellent stability, and biocompatibility.

The Potential of Plant Polysaccharides and Chemotherapeutic Drug Combinations in the Suppression of Breast Cancer

Breast cancer is the most common cancer affecting women worldwide. The associated morbidity and mortality have been on the increase while available therapies for its treatment have not been totally effective. The most common treatment, chemotherapy, sometimes has dangerous side effects because of non-specific targeting, in addition to poor therapeutic indices, and high dose requirements. Consequently, agents with anticancer effects are being sought that can reduce the side effects induced by chemotherapy while increasing its cytotoxicity to cancer cells. This is possible using natural compounds that are safe and biologically active. There are many reports on plant polysaccharides due to their bioactive and anticancer properties. The use of plant polysaccharide together with a conventional cytotoxic drug may offer wide benefits in cancer therapy, producing synergistic effects, thereby reducing drug dose and, so, its associated side effects. In this review, we highlight an overview of the use of plant polysaccharides and chemotherapeutic drugs in breast cancer preclinical studies, including their mechanisms of anticancer activities. The findings emphasize the potential of plant polysaccharides to improve chemotherapeutic outcomes in breast cancer, paving the way for more effective and safer treatment strategies.

OncoSexome: the landscape of sex-based differences in oncologic diseases

Abstract The NIH policy on sex as biological variable (SABV) emphasized the importance of sex-based differences in precision oncology. Over 50% of clinically actionable oncology genes are sex-biased, indicating differences in drug efficacy. Research has identified sex differences in non-reproductive cancers, highlighting the need for comprehensive sex-based cancer data. We therefore developed OncoSexome, a multidimensional knowledge base describing sex-based differences in cancer (https://idrblab.org/OncoSexome/) across four key topics: antineoplastic drugs and responses (SDR), oncology-related biomarkers (SBM), risk factors (SRF) and microbial landscape (SML). SDR covers sex-based differences in 2051 anticancer drugs; SBM describes 12 551 sex-differential biomarkers; SRF illustrates 350 sex-dependent risk factors; SML demonstrates 1386 microbes with sex-differential abundances associated with cancer development. OncoSexome is unique in illuminating multifaceted influences of biological sex on cancer, providing both external and endogenous contributors to cancer development and describing sex-based differences for the broadest oncological classes. Given the increasing global research interest in sex-based differences, OncoSexome is expected to impact future precision oncology practices significantly.

Repurposing of erythropoietin as a neuroprotective agent against methotrexate-induced neurotoxicity in rats

Background: Methotrexate (MTX) is a cytotoxic drug that can trigger neurotoxicity via enhancing oxidative stress, apoptosis, and inflammation. On the other hand, erythropoietin (EPO) functions as an antioxidant, anti-apoptotic, and anti-inflammatory agent, in addition to its hematopoietic effects. Aim: The present study was developed to examine the neuroprotective impact of EPO against MTX-provoked neurotoxicity in rats. Methods: Chemo fog was elicited in Wistar rats via injection of one dosage of MTX (20 mg/kg, i.p) on the sixth day of the study. EPO was injected at 500 IU/kg/day, i.p for 10 successive days. Results: MTX triggered memory and learning impairment as evidenced by Morris water maze, passive avoidance, and Y-maze cognitive tests. In addition, MTX induced oxidative stress as evident from the decline in hippocampal Nrf2 and HO-1 levels. MTX brought about apoptosis, as demonstrated by the elevation in p53, caspase-3, and Bax levels, as well as the decrease in Bcl2 levels. MTX also decreased Beclin-1, an autophagy-related marker, and increased P62 expression. In addition, MTX downregulated Sirt-1/AKT/FoxO3a pathway and increased miRNA-34a gene expression. Moreover, MTX increased acetylcholinesterase activity and reduced neurogenesis. EPO administration remarkably counteracted MTX-induced molecular and behavioral disorders in rat hippocampi. Conclusion: Our findings impart preclinical indication for repurposing of EPO as a promising neuroprotective agent through modulating miRNA-34a, autophagy, and the Sirt-1/FoxO3a signaling pathway.

The versatile NDI-based compounds: emerging anticancer and antimicrobial agents

The versatile NDI-based compounds: emerging anticancer and antimicrobial agents

Halogen‐based quinazolin‐4(3H)‐one derivatives as MCF‐7 breast cancer inhibitors: Current developments and structure–activity relationship

AbstractCurrently, cancer is a serious health challenge with predominance beyond restrictions. Breast cancer remains one of the major contributors to cancer‐related morbidity and mortality in women. Chemotherapy continues to be crucial in the treatment of all variants of cancer. Several antitumor drugs are presently in different phases of clinical trials, whereas many more have been approved for clinical use. However, these drugs have the potential to cause adverse effects, and certain individuals may become resistant to them, which would eventually reduce the drug's efficacy. Therefore, it is essential to discover, develop, and improve newer anticancer drug molecules that could potentially inhibit proliferative pathways. In recent years, quinazolinone derivatives, more specifically halogen‐substituted 4(3H)‐quinazolinone, have drawn attention as a promising new class of chemotherapeutic agents. In addition, these molecules showed significant inhibition in micromolar ranges when tested in vitro against the MCF‐7 cell line. Therefore, this study aims to emphasize the intriguing versatility of halogen atoms, providing an in‐depth summary and highlighting recent developments in the anticancer properties of halogenated 4(3H)‐quinazolinones. It also features a detailed discussion of the structure–activity relationship (SAR) of various functional groups and their interaction with amino acid residues utilizing molecular docking studies. The intent is to foster novel discoveries that can inspire innovative investigations in this domain. Hence, this study simplifies the drug design and development strategies by prolonging the array of pharmacologically active candidates.

Transarterial Chemoembolization in Locally Advanced Rectal Cancer: A Systematic Review

Background: Locally advanced rectal cancer (LARC) presents a significant treatment challenge. Transarterial chemoembolization (TACE) has emerged as a potential adjunctive treatment, offering targeted delivery of chemotherapeutic agents to the tumor site, minimizing systemic exposure. This systematic review aims to assess the current literature on this novel technique and evaluate the safety and efficacy profile of TACE in treating this complex cohort of patients. Methods: A comprehensive literature search was conducted across multiple databases, including PubMed, EMBASE, and Cochrane Library, to identify studies evaluating TACE in LARC. Inclusion criteria encompassed clinical trials, cohort studies, and case series reporting on outcomes such as tumor response rate, overall survival (OS), progression-free survival (PFS), and treatment-related adverse events. Results: A total of eight studies involving 543 patients met the inclusion criteria. The studies varied in design, with five prospective and three retrospective studies. A higher prevalence of male participants (68.7%) was noted, with a median age of 60.3 years. The studies primarily evaluated the efficacy and safety of TACE in LARC treatment. Pathological response rates, tumor reduction, and survival outcomes varied across studies, with TACE showing promise in reducing tumor size, improving survival, and controlling metastasis. Major complications were rare, reported in 6.0% of cases. Conclusions: TACE is a promising therapeutic option for patients with LARC, demonstrating favorable tumor response rates and manageable toxicity profiles. Further large-scale, randomized controlled trials are warranted to confirm these findings and better define the role of TACE in the multimodal treatment of LARC.

IL-13Rα2 Is Involved in Resistance to Doxorubicin and Survival of Osteosarcoma Patients

Background/Objectives: Interleukin 13 receptor alpha 2 (IL-13Rα2) is a receptor with a high affinity for IL-13 and is involved in the progression of human cancers. However, studies on the role of IL-13Rα2 in osteosarcoma are limited. Therefore, this study aimed to investigate the expression and roles of IL-13Rα2 in the progression of osteosarcoma. Methods: This study evaluated the roles of IL-13Rα2 in osteosarcomas by evaluating tumor tissues from 37 human osteosarcomas and osteosarcoma cells. Results: Immunohistochemical positivity of IL-13Rα2 was an independent indicator of shorter overall survival and relapse-free survival of 37 osteosarcoma patients and 26 subpopulations of patients who received adjuvant chemotherapy with multivariate analysis. In U2OS and KHOS/NP osteosarcoma cells, overexpression of IL-13Rα2 significantly increased proliferation, migration, and invasion of cells, all of which decreased with knockdown of IL-13Rα2. Overexpression of IL-13Rα2 increased expression of TGF-β, snail, cyclin D1, and BCL2 but decreased BAX, and knockdown of IL-13Rα2 caused a decrease in expression of these molecules. In addition, both in vitro and in vivo, proliferation of osteosarcoma cells increased, and apoptosis decreased with overexpression of IL-13Rα2 under treatment with doxorubicin. Knockdown of IL-13Rα2 sensitized osteosarcoma cells to the cytotoxic effect of doxorubicin. Conclusions: The results of this study suggest that the expression of IL13Rα2 might be used as a potential prognostic indicator in osteosarcoma patients. Furthermore, it is observed that IL13Rα2 influences the resistance to the chemotherapeutic agent doxorubicin. Therefore, a therapeutic trial targeting IL13Rα2 might be a new therapeutic strategy for osteosarcoma, especially those highly expressing IL13Rα2.

Preparation and Evaluation of pH-Sensitive Chitosan/Alginate Nanohybrid Mucoadhesive Hydrogel Beads: An Effective Approach to a Gastro-Retentive Drug Delivery System

Background: Despite extensive research over the decades, cancer therapy is still a great challenge because of the non-specific delivery of chemotherapeutic agents, which could be overcome by limiting the distribution of chemotherapeutic agents toward cancer cells. Objective: To reduce the cytolytic effects against cancer cells, graphene oxide (GO) nanoparticles (NPs) can load anticancer medicines and genetic tools. Methodology: During the current study, folic-acid-conjugated graphene oxide (Fa-GO) hybrid mucoadhesive chitosan (CS)-based hydrogel beads were fabricated through an “ion-gelation process”, which allows for regulated medication release at malignant pH. Results: The fabricated chitosan–alginate (SA-CS) hydrogel beads were examined using surface morphology, optical microscopy, XRD, FTIR, and homogeneity analysis techniques. The size analysis indicated that the size of the Fa-GO was up to 554.2 ± 95.14 nm, whereas the beads were of a micrometer size. The folic acid conjugation was confirmed by NMR. The results showed that the craggy edges of the graphene oxide were successfully encapsulated in a polymeric matrix. The mucoadhesive properties were enhanced with the increase in the CS concentration. The nanohybrid SA-CS beads exhibited good swelling properties, and the drug release was 68.29% at pH 5.6 during a 24 h investigation. The accelerated stability study, according to ICH guidelines, indicated that the hydrogel beads have a shelf-life of more than two years. Conclusions: Based on the achieved results, it can be concluded that this novel gastro-retentive delivery system may be a viable and different way to improve the stomach retention of anticancer agents and enhance their therapeutic effectiveness.

Leveraging homologous recombination deficiency for sarcoma

Abstract Background Homologous recombination deficiency (HRD) in tumors correlates with poor prognosis and metastases development. Determining HRD is of major clinical relevance as it can be treated with PARP inhibitors (PARPi). HRD remains poorly investigated in sarcoma, a rare and heterogeneous cancer of mesenchymal origin. Objective We aimed (i) to investigate predictive biomarkers of HRD in several independent sarcoma cohorts using a cross-functional strategy by combining genomic, transcriptomic and phenotypic approaches and (ii) to evaluate the therapeutic potential of PARPi and DNA damage response (DDR)-based therapies ex vivo. Materials and methods We performed a comprehensive genomic and transcriptomic characterization of sarcoma using datasets from The Cancer Genome Atlas (TCGA) and Therapeutically Applicable Research to Generate Effective Treatments (TARGET), and our own bone and soft tissue sarcoma cohorts. We evaluated PARP1/2 and WEE1 inhibition ex vivo in patient-derived sarcoma cell models as monotherapy and in combination with chemotherapeutic agents to identify synergistic effects. Results Firstly, we identified genomic traits of HRD in a subset of sarcomas associated with molecular alterations in homologous recombination repair (HRR) pathway genes and high chromosomal instability. Secondly, we identified and validated distinct SARC-HRD transcriptional signatures that predicted sensitivity to PARPi. Finally, we showed functional defects in HRR in sarcoma cells that were associated with functional dependency towards PARPi and WEE1i and support the clinical use of RAD51 as a predictive biomarker for PARPi sensitivity. Conclusion We provide a personalized oncological approach to potentially improve the treatment of sarcoma patients. We encourage the evaluation of gene expression signatures to enhance the identification of patients who might benefit from DDR-based therapies.

Abstract B070: Dissecting EV dynamics in the sequestration of doxorubicin from breast cancer cells

Abstract Background: Extracellular vesicles (EVs) are one of the three main analytes sought for in liquid biopsy development. EVs are released by all cell types including cancer cells and play a crucial role in cell-cell communication. Breast cancer cells have been shown to utilize EVs as a mechanism to sequester chemotherapeutic agents, thereby conferring resistance to treatment. This study investigates the role of EVs in doxorubicin (DOX) resistance in MDA-MB-231 breast cancer cells. Method: MDA-MB-231 cells were exposed to increasing dose of anthracycline for 6 and 12 months. Resistance was confirmed by cytotoxicity assay and western blot. Resistant and parent cells were labeled for immunohistochemistry and their EVs were isolated via ultracentrifugation. EVs were analysed using nanoscale flow cytometry and sent for mass spectrophotometry. Result: Using nanoscale flow cytometry, we optimized a method to detect DOX-carrying EVs based on the intrinsic fluorescence of the drug. We found that DOX-resistant cells exhibited lower intracellular DOX accumulation and higher expression of the EV marker CD63 compared to their parental counterparts. Conclusion: These results suggest that chemoresistant breast cancer cells may alter their EV production machinery to evade the lethal effects of DOX. Understanding this mechanism could lead to novel strategies to overcome chemoresistance in breast cancer. Citation Format: Sina Halvaei, Jing Xu, Suganthi Chittaranjan, Sharon Gorski, Karla Williams. Dissecting EV dynamics in the sequestration of doxorubicin from breast cancer cells [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B070.

Targeting Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2): Latest Insights on Synthetic Strategies

Vascular endothelial growth factor receptor 2 (VEGFR-2) is a crucial mediator of angiogenesis, playing a pivotal role in both normal physiological processes and cancer progression. Tumors harness VEGFR-2 signaling to promote abnormal blood vessel growth, which is a key step in the metastasis process, making it a valuable target for anticancer drug development. While there are VEGFR-2 inhibitors approved for therapeutic use, they face challenges like drug resistance, off-target effects, and adverse side effects, limiting their effectiveness. The quest for new drug candidates with VEGFR-2 inhibitory activity often starts with the selection of key structural motifs present in molecules currently used in clinical practice, expanding the chemical space by generating novel derivatives bearing one or more of these moieties. This review provides an overview of recent advances in the development of novel VEGFR-2 inhibitors, focusing on the synthesis of new drug candidates with promising antiproliferative and VEGFR-2 inhibition activities, organizing them by relevant structural features.

Green Synthesis of Silver Nanoparticles Using Doxycycline: Evaluation of Antimicrobial Potential and Organ-specific Toxicity

Silver nanoparticles (Ag-NPs) have wide applicability as antimicrobial, biomedical, and anti-cancer drug delivery systems. This study aimed to synthesize Ag-NPs using green methodology to assess their antimicrobial properties and toxicity. Ag-NPs were prepared using doxycycline, an antibiotic serving as a reducing and capping agent. The synthesized Ag-NPs were characterized by ultraviolet-visible spectrophotometry, X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectrometry. The antimicrobial efficacy of doxycycline-mediated Ag-NPs was assessed on Candida species in vitro and for toxicity in male albino mice in vivo. The Ag-NPs showed a surface plasmon resonance at 411 nm, indicating a 90 nm average size and spherical shape. Toxicity was tested on mouse organs (liver, kidney, spleen, heart and stomach) using three Ag-NP doses (50, 100, 200 mg/kg) over 14 days. The synthesized Ag-NPs produced large inhibition zones against two well-known fungal species, C. albicans and C. tropicalis, demonstrating their antimicrobial potential. The Ag-NPs showed varying degrees of toxicity in different mouse organs, depending on the administered dose, with more pronounced adverse effects observed at higher concentrations. Periodic administration of Ag-NPs at low-dose volumes holds promise as a safe approach to their use as antimicrobial agents. Low-dose Ag-NPs are minimally toxic and show strong antimicrobial efficacy.