Role of Small Molecule Targeted Compounds in Cancer: Progress, Opportunities, and Challenges

Formulation and development of ACUPA-targeting PEGylated nanoliposomes for treatment of prostate cancer

A promising strategy for improving the effectiveness, specificity and safety of cancer treatment is targeted medication delivery. Prostate-specific membrane antigen (PSMA) is an effective biomarker for tracking and treating prostate cancer. In this study, we developed a PSMA-targeted drug delivery system by modifying PEGylated liposomal doxorubicin (PLD) with 2-(3-((S)-5-amino-1-carboxypentyl) ureido) pentanedioic acid (ACUPA), a small-molecule PSMA inhibitor, to enhance tumor targeting and therapeutic outcomes. The physicochemical characterization of ACUPA-functionalized PLD (ACUPA-PLD) confirmed successful conjugation, with a slight increase in particle size and a minor decrease in surface charge compared to unmodified PLD. In vitro studies demonstrated that ACUPA-PLD exhibited significantly enhanced cellular uptake and cytotoxicity in PSMA-expressing LNCaP prostate cancer cells compared to non-targeted PLD, whereas PSMA-negative PC3 cells showed no significant difference in uptake or cytotoxicity. Flow cytometry and fluorescence-based assays confirmed PSMA-mediated internalization of ACUPA-PLD. In vivo biodistribution studies in a LNCaP xenograft nude mouse model revealed that ACUPA-PLD accumulated preferentially in tumor tissues. Pharmacokinetic analysis indicated that ACUPA functionalization slightly reduced the half-life of PLD without significantly altering its clearance profile. Chemotherapy studies demonstrated that ACUPA-PLD exhibited superior tumor growth inhibition compared to non-targeted PLD, supporting the potential of ACUPA-mediated targeting to improve the therapeutic index of liposomal chemotherapy. These findings suggest that ACUPA-functionalized liposomes represent a promising approach for PSMA-targeted prostate cancer therapy.

Structural optimization and pharmacological evaluation of diphenyl amine esters as anti-hepatocellular carcinoma agents by targeting TAR RNA-binding protein 2

Hepatocellular Carcinoma (HCC), a leading cause of cancer-related death in the world, urgently requires novel therapeutic strategies and drug targets. The TRBP-Dicer complex plays a critical role in miRNA biosynthesis, which can be regulated by small molecules to exert anti-cancer effects. This study presented the structural modification of the natural product (-)-Gomisin M1(GM), resulting in the synthesis of 37 derivatives with a diphenyl amine ester scaffold. Several of these derivatives exhibited enhanced modulation of miRNA biogenesis compared to GM. Notably, derivative 13j displayed improved binding affinity to TRBP and greater efficacy in modulating miRNA biosynthesis, as well as anti-HCC activity in vitro and in vivo. Further investigation revealed that 13j induced apoptosis and pyroptosis while inhibiting the epithelial-to-mesenchymal transition process in HCC cells. In terms of druggability, 13j possesses favorable drug-likeness and a promising safety profile. These findings provide a promising scaffold with potent activity and low toxicity, offering a foundation for the development of miRNA-based therapeutic strategies for HCC.

Reshaping the landscape of locoregional treatments for breast cancer liver metastases: A novel, intratumoral, p21-targeted percutaneous therapy increases survival in BALB/c mice inoculated with 4T1 triple negative breast cancer cells in the liver

Patients with disseminated metastatic disease from breast cancer are likely to have liver involvement in >50% of cases at some point during disease progression. These patients have a poor prognosis; and, when treated with the standard of care systemic therapy they have a median survival of <9-months. Increasing survival in breast cancer patients will likely require the administration of better therapies that are specifically targeted to treat distant metastases. One approach to increasing treatment efficacy for breast cancer liver metastases is through the application locoregional therapies. Locoregional therapies are an appealing interventional approach for breast cancer patients with liver metastases since these tumor lesions are accessible via minimally invasive procedures that can be administered using either ultrasound or CT imaging. Current locoregional therapies to treat breast cancer liver metastases are non-specific and have not produced significant increases in survival. The goal of this study was to design and test a targeted locoregional therapeutic intervention for breast cancer liver metastases. The lead candidate, a fixed-dose small-molecule drug called MBC-005, was tested in vitro and then the efficacy was evaluated in a BALB/c mouse liver metastases model. A novel formulation of N-allyl noroxymorphone hydrochloride incorporated into an alginate-based gel overcomes many of the limitations associated with the administration of small-molecule drugs, which include solubility, off-target toxicity, and enzymatic degradation. In vitro results demonstrated that MBC-005 mediated its anti-tumorigenic effect through a p21-dependent mechanism via a novel molecular pathway, in which N-allyl noroxymorphone component of MBC-005 stimulated the opioid growth factor receptor to increase p21 expression. Intratumoral administration of MBC-005 increased survival 3.9-fold in mice and significantly decreased tumor volume 4-fold. While many cytotoxic therapies increase p21 expression as a response to DNA damage, MBC-005 increased p21 expression independent cytotoxic DNA damage. MBC-005 did not induce off-target toxicity; and, as such, would be amenable to multiple rounds of administration. Nevertheless, it is notable that the positive effects of MBC-005 treatment on increasing survival and decreasing tumor volume in mice was achieved using a single dose.

Evernic Acid: A Low-Toxic and Selective Alternative to Chemotherapeutic Agents in the Treatment of Ovarian Cancer

Evernic acid (EA) has emerged as a potential therapeutic agent with its low toxicity and anticancer properties. In this study, the anticancer effect of EA on ovarian cancer cell lines and normal ovarian surface epithelial cells (OSE) was evaluated. The antiproliferative effect of EA was evaluated by xCELLigence Real-Time Cell analysis, colony formation assay, and acridine orange and DAPI staining methods. Genotoxicity analysis was performed by comet assay. The effect of EA on cell migration was analyzed by wound healing assay. The potential of EA to induce apoptosis was also determined by evaluating the changes in gene and protein expression levels by qRT-PCR and Western blot analysis, respectively. EA was found to be a promising potential therapeutic agent for ovarian cancer without showing significant cytotoxic effect on normal cells. Furthermore, EA decreased the ability of ovarian cancer cells for migration, increased the rate of apoptosis by inhibiting BIRC5 and activating CASP3, triggered cell cycle arrest in the G2/M phase, and caused a decrease in mitochondrial membrane potential and genotoxic effects. The results have shown that EA could be an effective candidate molecule for ovarian cancer treatment.

A promising future for breast cancer therapy with hydroxamic acid-based histone deacetylase inhibitors

Histone deacetylases (HDACs) play a critical role in chromatin remodelling and modulating the activity of various histone proteins. Aberrant HDAC functions has been related to the progression of breast cancer (BC), making HDAC inhibitors (HDACi) promising small-molecule therapeutics for its treatment. Hydroxamic acid (HA) is a significant pharmacophore due to its strong metal-chelating ability, HDAC inhibition properties, MMP inhibition abilities, and more. They were found to increase the efficacy of the approved drugs when used in combination. In this review we presented bioinformatic analysis using available data from the Cancer Genome Atlas and Genotype-Tissue Expression databases, outlined the recent advancements in the application of HA-based HDACi for BC during preclinical investigation and clinical trials, tried to offer the rationale for targeting HDAC in BC with HA-based HDACi, summarised the challenges faced in the successful clinical application of HDACi, and proposed potential strategies to address these challenges, aiming to enhance treatment outcomes in BC. Abbreviations: ABCG2, ATP-binding cassette super-family G member 2; ABC, ATP-binding cassette; ADP, Adenosine diphosphate; APC, Antigen presenting cell; AML, Acute myeloid leukemia; ARH1, Aplysia ras homolog 1; BCRP, Breast cancer resistance protein; BRCA, Breast invasive carcinoma; Bax, B-cell lymphoma associated X; CK5, Cytokeratin 5; CK14, Cytokeratin 14; CK17, Cytokeratin 17; CoRESTMiDAC, Co-repressor for element-1-silencing transcription factor; CRM1, Chromosomal maintenance 1; CTCL, Cutaneous T-cell lymphoma; DNMT, DNA methyltransferase; DFS, Disease-free survival; ER, Oestrogen receptor; EMT, Epithelial-mesenchymal transition; FGFR1, Fibroblast growth factor receptor 1; GEPIA, Gene Expression Profiling Interactive Analysis; GTEx, Genotype tissue expression; HAT, Histone acetylase; HDAC, Histone deacetylase; HDF, Human dermal fibroblast; HER2, Human epidermal growth factor receptor 2; HDLP, Histone deacetylase-like protein; Hsp90, Heat shock protein 90; HSF1, Heat shock factor 1; HeLa, Henrietta Lacks; HER1, Human epidermal growth factor receptor 1; IARC, International Agency for Research on Cancer; IL-10, Interleukin-10; KAP1, KRAB associated protein 1; MDM2, Mouse double minute 2 homolog; MDR, Multidrug resistance; MCF-7, Michigan cancer foundation-7; MEF-2, Myocyte enhancer factor-2MMP- Matrix metalloproteinase; NAD, Nicotinamide adenine dinucleotide; NuRD, Nucleosome remodelling and deacetylation; NF- κ B, Nuclear factor kappa light chain enhancer of activated B cell; NES, Nuclear export signal; NLS, Nuclear localization signal; NCoR, Nuclear receptor corepressor; NCT, National clinical trial; OS, Overall survival; PR, Progesterone receptor; PI3K, Phosphoinositide 3-kinase; PAX3, Paired box gene 3; P-gp, P-glycoprotein; ROS, Reactive oxygen species; SIRT, Sirtuin; SMRT, Silencing mediator for retinoid and thyroid receptor; STAT3, Signal transducer and activator of transcription-3; SAR, Structure-activity relationship; SHP1, Src homology region 2 domain-containing phosphatase 1; SAHA, Suberoylanilide hydroxamic acid; SMEDDS, Self micro emulsifying drug delivery system; TNBC, Triple-negative breast cancer; TSA, Trichostatin A; ZBG, Zinc binding group.

Journey of PROTAC: From Bench to Clinical Trial and Beyond

Proteolysis-targeting chimeras (PROTACs) represent a transformative advancement in drug discovery, offering a method to degrade specific intracellular proteins. Unlike traditional inhibitors, PROTACs are bifunctional molecules that target proteins for elimination, enabling the potential treatment of previously "undruggable" proteins. This concept, pioneered by Crews and his team, introduced the use of small molecules to link a target protein to an E3 ubiquitin ligase, inducing ubiquitination and subsequent degradation of the target protein. By promoting protein degradation rather than merely inhibiting function, PROTACs present a novel therapeutic strategy with enhanced specificity and effectiveness, especially in areas such as cancer and neurodegenerative diseases. Since their initial discovery, the field of PROTAC research has rapidly expanded with numerous PROTACs now designed to target a wide range of disease-relevant proteins. The substantial research, investment, and collaboration across academia and the pharmaceutical industry reflect the growing interest in PROTACs. This Review discusses the journey of PROTACs from initial discovery to clinical trials, highlighting advancements and challenges. Additionally, recent developments in fluorescent and photogenic PROTACs, used for real-time tracking of protein degradation, are presented, showcasing the evolving potential of PROTACs in targeted therapy.

Design, Synthesis, and Evaluation of Trihalomethyl Ketone Derivatives of Neocarzilin A as Improved Antimetastatic Agents

Vesicle Amine Transport-1 (VAT1) is a protein that is overexpressed in many cancers, including breast cancer, glioblastoma, and angiosarcoma. High VAT1 expression correlates with poor overall survival, and genetic knockout models of VAT1 indicate potent antimigratory activity, suggesting that VAT1 is a promising antimetastasis target. Recently, the natural product neocarzilin A (NCA) from Streptomyces carzinostaticus was reported to be the first validated small-molecule inhibitor of VAT1, having strong activity in metastasis models of angiosarcoma and breast cancer. While knockdown of VAT1 has no effect on cell viability, NCA has significant cytotoxicity, suggesting that NCA is not selective for VAT1. Additionally, NCA has poor aqueous solubility, making in vivo administration of NCA challenging and thus limiting its therapeutic potential. Here, we report the design, synthesis, bioactivity, and pharmacokinetics of novel NCA derivatives with improved drug-like properties. Specifically, we have developed derivatives with altered warheads, replacing chlorines on the trichloroketone with fluorines. Using a modified synthetic route, we accessed NCA derivatives with greater than 25-fold improvements in solubility and 30-fold improvements in the antimigratory to antiproliferative bioactivity ratio. The two best derivatives, along with the parent, were analyzed for oral bioavailability, with the two more soluble derivatives showing greatly improved bioavailability. Overall, these studies have resulted in the development of VAT1 inhibitors with improved properties, which will enable further study of the pharmacological inhibition of VAT1 as an antimetastatic strategy. Additionally, these studies provide insights into novel trihalomethyl ketone warheads and identify chlorodifluoroketone as a potent and selective new warhead.

Reshaping the Landscape of Locoregional Treatments for Breast Cancer Liver Metastases: A novel, intratumoral, p21-targeted percutaneous therapy increases survival in BALB/c mice inoculated with 4T1 triple negative breast cancer cells in the liver

Patients with disseminated metastatic disease from breast cancer are likely to have liver involvement in >50% of cases at some point during disease progression. These patients have a poor prognosis; and, when treated with the standard of care systemic therapy they have a median survival of <9-months. Increasing survival in breast cancer patients will likely require the administration of better therapies that are specifically targeted to treat distant metastases. One approach to increasing treatment efficacy for breast cancer liver metastases is through the application locoregional therapies. Locoregional therapies are an appealing interventional approach for breast cancer patients with liver metastases since these tumor lesions are accessible via minimally invasive procedures that can be administered using either ultrasound or CT imaging. Current locoregional therapies to treat breast cancer liver metastases are non-specific and have not produced significant increases in survival. The goal of this study was to design and test a targeted locoregional therapeutic intervention for breast cancer liver metastases. The lead candidate, a fixed-dose small-molecule drug called MBC-005, was tested in vitro and then the efficacy was evaluated in a BALB/c mouse liver metastases model. A novel formulation of N-allyl noroxymorphone hydrochloride incorporated into an alginate-based gel overcomes many of the limitations associated with the administration of small-molecule drugs, which include solubility, off-target toxicity, and enzymatic degradation. In vitro results demonstrated that MBC-005 mediated its anti-tumorigenic effect through a p21-dependent mechanism via a novel molecular pathway, in which N-allyl noroxymorphone component of MBC-005 stimulated the opioid growth factor receptor to increase p21 expression. Intratumoral administration of MBC-005 increased survival 3.9-fold in mice and significantly decreased tumor volume 4-fold. While many cytotoxic therapies increase p21 expression as a response to DNA damage, MBC-005 increased p21 expression independent cytotoxic DNA damage. MBC-005 did not induce off-target toxicity; and, as such, would be amenable to multiple rounds of administration. Nevertheless, it is notable that the positive effects of MBC-005 treatment on increasing survival and decreasing tumor volume in mice was achieved using a single dose.

Developing new anticancer agents: Design, synthesis, biological evaluation and in silico study of several functionalized pyrimidine-5-carbonitriles as small molecules modulators targeting breast cancer

Committed to our growing effort addressed toward the development of potent anti-breast cancer candidates, new 4-hydrazinylpyrimidine-5-carbonitriles featuring a morpholinyl or piperidinyl moiety at the position-2 and derivatized with various functionalities at the hydrazinyl group were designed through structure optimization, and their antiproliferative potency against two human breast cancer (BC) cell lines, relative to the reference drug 5-FU, was evaluated. Compounds showing remarkable cytotoxic activity versus the hormone dependent MCF-7 cell line (IC50 = 1.62 ± 0.06 µM- 9.88 ± 0.38 µM) and the non-hormone dependent MDA-MB-231 cell line (IC50 = 3.26 ± 0.14 µM-12.93 ± 0.55 µM) were further tested by multiple assays for clarification of their potential activity. Promising derivatives revealing low damage to healthy cells were subject to enzymatic inhibitory assessment against ARO and EGFR and their activities compared to letrozole and erlotinib respectively. Compounds 3c, 6a as well as compounds 4c, 4d proved to be good inhibitors of the ARO and EGFR enzymes respectively. Active compounds were also evaluated for their underlying mode of action by further investigation for CDK, Hsp90, PI3K inhibition and compared to normal MCF-10A cells and assessed for their enhancement of the caspase 9 levels. Additionally, cell cycle analysis and apoptotic induction were performed. They demonstrated remarkable activities in the previous assays and emanated as leads as anti-breast cancer candidates. Eventually, molecular docking analysis revealed that hit compounds 3c, 4c, 4d, and 6a could bind favorably to the proposed in silico models of various protein-ligand interactions. Therefore, our promising top candidates, by demonstrating appreciable anti-breast cancer activities, present valuable prospects for optimization, potency enhancement and future application.

Development of natural product-based targeted protein degraders as anticancer agents

Targeted protein degradation (TPD) has emerged as a powerful approach for eliminating cancer-causing proteins through an "event-driven" pharmacological mode. Proteolysis-targeting chimeras (PROTACs), molecular glues (MGs), and hydrophobic tagging (HyTing) have evolved into three major classes of TPD technologies. Natural products (NPs) are a primary source of anticancer drugs and have played important roles in the development of TPD technology. NPs potentially expand the toolbox of TPD by providing a variety of E3 ligase ligands, protein of interest (POI) warheads, and hydrophobic tags (HyTs). As a promising direction in the TPD field, NP-based degraders have shown great potential for anticancer therapy. In this review, we summarize recent advances in the development of NP-based degraders (PROTACs, MGs and HyTing) with anticancer applications. Moreover, we put forward the challenges while presenting potential opportunities for the advancement of future targeted protein degraders derived from NPs.

Application of Fluorescence- and Bioluminescence-Based Biosensors in Cancer Drug Discovery

Recent advances in drug discovery have established biosensors as indispensable tools, particularly valued for their precision, sensitivity, and real-time monitoring capabilities. The review begins with a brief overview of cancer drug discovery, underscoring the pivotal role of biosensors in advancing cancer research. Various types of biosensors employed in cancer drug discovery are then explored, with particular emphasis on fluorescence- and bioluminescence-based technologies such as FRET, TR-FRET, BRET, NanoBRET, and NanoBiT. These biosensors have enabled breakthrough discoveries, including the identification of Celastrol as a novel YAP-TEAD inhibitor through NanoBiT-based screening, and the development of TR-FRET assays that successfully identified Ro-31-8220 as a SMAD4R361H/SMAD3 interaction inducer. The integration of biosensors in high throughput screening and validation for cancer drug compounds is examined, highlighting successful applications such as the development of LATS biosensors that revealed VEGFR as an upstream regulator of the Hippo signaling pathway. Real-time monitoring of cellular responses through biosensors has yielded invaluable insights into cancer cell signaling pathways, as demonstrated by NanoBRET assays detecting RAF dimerization and HiBiT systems monitoring protein degradation dynamics. The review addresses challenges linked to biosensor applications, such as maintaining stability in complex tumor microenvironments and achieving consistent sensitivity in HTS applications. Emerging trends are discussed, including integrating artificial intelligence and advanced nanomaterials for enhanced biosensor performance. In conclusion, this review offers a comprehensive analysis of fluorescence- and bioluminescence-based biosensor applications in the dynamic cancer drug discovery field, presenting quantitative evidence of their impact and highlighting their potential to revolutionize targeted cancer treatments.

Targeting APC/C Ubiquitin E3-Ligase Activation with Pyrimidinethylcarbamate Apcin Analogues for the Treatment of Breast Cancer

Activation of the ubiquitin ligase APC/C by the protein Cdc20 is an essential requirement for proper cell division in higher organisms, including humans. APC/C is the ultimate effector of the Spindle Assembly Checkpoint (SAC), the signalling system that monitors the proper attachment of chromosomes to microtubules during cell division. Defects in this process result in genome instability and cancer. Interfering with APC/C substrate ubiquitylation in cancer cells delays mitotic exit, which induces cell death. Therefore, impairing APC/C function represents an opportunity for the treatment of cancer and malignancies associated with SAC dysregulation. In this study, we report a new class of pyrimidinethylcarbamate apcin analogues that interfere with APC/C activity in 2D and 3D breast cancer cells. The new pyrimidinethylcarbamate apcin analogues exhibited higher cytotoxicity than apcin in all breast cancer cell subtypes investigated, with much lower cytotoxicity observed in fibroblasts and RPE-1 cells. Further molecular rationalisation of apcin and its derivatives was conducted using molecular docking studies. These structural modifications selected from the in silico studies provide a rational basis for the development of more potent chemotypes to treat highly aggressive breast cancer and possibly other aggressive tumour types of diverse tissue origins.

Novel oxadiazole-thiadiazole derivatives: synthesis, biological evaluation, and in silico studies

In the search for new anticancer agents, we synthesized a new series of thiazole derivatives carried on thiadiazole-oxadiazole hybrid. Final compounds (5a-5i) were analyzed via 1H NMR, 13C NMR, and HRMS. The pharmacokinetic profile of the targeted compounds was predicted via in silico calculations. Their anticancer properties were determined using MTT method against MCF7 and A549 cell lines. Compounds 5a, 5b and 5c were found more active against MCF7 cells than A549 cells while they were not cytotoxic on L929 healthy cells. Generally, it can be summarized that acetamide moiety has a pivotal role in anticancer activity. For further studies, their aromatase inhibitory activity was evaluated. After determination all these features, the binding modes of the active compounds and the stability and relation of the ligand-enzyme complex were investigated using molecular docking and molecular dynamics simulation studies, respectively. In vitro and in silico studies suggest two important structure-activity relationship (SAR) points that at least one azole ring is essential, and if there is approximately 8.0 ± 0.5 Å distance between the H-bond rich zone of ligand and the heteroaryl ring system of ligand has a major impact on aromatase inhibitory activity. Compounds with small group substitution on thiazole are found potentially may be used for the treatment of anti-breast cancer orally.Communicated by Ramaswamy H. Sarma.

Current status and trends in small nucleic acid drug development: Leading the future

Small nucleic acid drugs, composed of nucleotides, represent a novel class of pharmaceuticals that differ significantly from conventional small molecule and antibody-based therapeutics. These agents function by selectively targeting specific genes or their corresponding messenger RNAs (mRNAs), further modulating gene expression and regulating translation-related processes. Prominent examples within this category include antisense oligonucleotides (ASO), small interfering RNAs (siRNAs), microRNAs (miRNAs), and aptamers. The emergence of small nucleic acid drugs as a focal point in contemporary biopharmaceutical research is attributed to their remarkable specificity, facile design, abbreviated development cycles, expansive target spectrum, and prolonged activity. Overcoming challenges such as poor stability, immunogenicity, and permeability issues have been addressed through the integration of chemical modifications and the development of drug delivery systems. This review provides an overview of the current status and prospective trends in small nucleic acid drug development. Commencing with a historical context, we introduce the primary classifications and mechanisms of small nucleic acid drugs. Subsequently, we delve into the advantages of the U.S. Food and Drug Administration (FDA) approved drugs and mainly discuss the challenges encountered during their development. Apart from researching chemical modification and delivery system that efficiently deliver and enrich small nucleic acid drugs to target tissues, promoting endosomal escape is a critical scientific question and important research direction in siRNA drug development. Future directions in this field will prioritize addressing these challenges to facilitate the clinical transformation of small nucleic acid drugs.

Opportunities and Challenges of Small Molecule Inhibitors in Glioblastoma Treatment: Lessons Learned from Clinical Trials

Glioblastoma (GBM) is the most prevalent central nervous system tumour (CNS). Patients with GBM have a dismal prognosis of 15 months, despite an intensive treatment schedule consisting of surgery, chemoradiation and concurrent chemotherapy. In the last decades, many trials have been performed investigating small molecule inhibitors, which target specific genes involved in tumorigenesis. So far, these trials have been unsuccessful, and standard of care for GBM patients has remained the same since 2005. This review gives an overview of trials investigating small molecule inhibitors on their own, combined with chemotherapy or other small molecule inhibitors. We discuss possible resistance mechanisms in GBM, focussing on intra- and intertumoral heterogeneity, bypass mechanisms and the influence of the tumour microenvironment. Moreover, we emphasise how combining inhibitors can help overcome these resistance mechanisms. We also address strategies for improving trial outcomes through modifications to their design. In summary, this review aims to elucidate different resistance mechanisms against small molecule inhibitors, highlighting their significance in the search for novel therapeutic combinations to improve the overall survival of GBM patients.

MLASM: Machine learning based prediction of anticancer small molecules

Cancer, being the second leading cause of death globally. So, the development of effective anticancer treatments is crucial in the field of medicine. Anticancer peptides (ACPs) have shown promising therapeutic potential in cancer treatment compared to traditional methods. However, the process of identifying ACPs through experimental means is often time-intensive and expensive. To overcome this issue, we employed a machine learning-based approach for the first time to develop an anticancer model using small molecules. Anticancer small molecules (ACSMs) are compounds that have been developed to target and inhibit cancer cells. In this study, we used 10,000 compounds to develop the machine learning models using five algorithms such as, Random Forest (RF), Light gradient boosting machine (LightGBM), K-nearest neighbors (KNN), Decision tree (DT) and Extreme Gradient Boosting (XGB). The developed models were evaluated using the test set and top three models were identified (RF, LightGBM and XGB). Furthermore, to validate the predictive performance of our models, we have performed external validation using an FDA approved anticancer compounds/drugs. Following this analysis, we found that our LightGBM model correctly predicted 9 compounds as active. However, RF and XGB exhibited some limitations by predicting 8 and 7 compounds as active out of 10, respectively. These results demonstrate that, when compared to RF and XGB, the LightGBM model showcase robust prediction capabilities, achieving a superior accuracy of 79% with an AUC of 0.88. These findings provide promising insights into the potential of our approach for predicting anticancer small molecules, highlighting the role of machine learning in advancing cancer treatment research.

Complex Interplay between DNA Damage and Autophagy in Disease and Therapy

Cancer, a multifactorial disease characterized by uncontrolled cellular proliferation, remains a global health challenge with significant morbidity and mortality. Genomic and molecular aberrations, coupled with environmental factors, contribute to its heterogeneity and complexity. Chemotherapeutic agents like doxorubicin (Dox) have shown efficacy against various cancers but are hindered by dose-dependent cytotoxicity, particularly on vital organs like the heart and brain. Autophagy, a cellular process involved in self-degradation and recycling, emerges as a promising therapeutic target in cancer therapy and neurodegenerative diseases. Dysregulation of autophagy contributes to cancer progression and drug resistance, while its modulation holds the potential to enhance treatment outcomes and mitigate adverse effects. Additionally, emerging evidence suggests a potential link between autophagy, DNA damage, and caretaker breast cancer genes BRCA1/2, highlighting the interplay between DNA repair mechanisms and cellular homeostasis. This review explores the intricate relationship between cancer, Dox-induced cytotoxicity, autophagy modulation, and the potential implications of autophagy in DNA damage repair pathways, particularly in the context of BRCA1/2 mutations.

Recent Update on Nanocarrier(s) as the Targeted Therapy for Breast Cancer

Despite ongoing advances in cancer therapy, the results for the treatment of breast cancer are not satisfactory. The advent of nanotechnology promises to be an essential tool to improve drug delivery effectiveness in cancer therapy. Nanotechnology provides an opportunity to enhance the treatment modality by preventing degradation, improving tumour targeting, and controlling drug release. Recent advances have revealed several strategies to prevent cancer metastasis using nano-drug delivery systems (NDDS). These strategies include the design of appropriate nanocarriers loaded with anti-cancer drugs that target the optimization of physicochemical properties, modulate the tumour microenvironment, and target biomimetic techniques. Nanocarriers have emerged as a preferential approach in the chemotropic treatment for breast cancer due to their pivotal role in safeguarding the therapeutic agents against degradation. They facilitate efficient drug concentration in targeted cells, surmount the resistance of drugs, and possess a small size. Nevertheless, these nanocarrier(s) have some limitations, such as less permeability across the barrier and low bioavailability of loaded drugs. To overcome these challenges, integrating external stimuli has been employed, encompassing infrared light, thermal stimulation, microwaves, and X-rays. Among these stimuli, ultrasound-triggered nanocarriers have gained significant attention due to their cost-effectiveness, non-invasive nature, specificity, ability to penetrate tissues, and capacity to deliver elevated drug concentrations to intended targets. This article comprehensively reviews recent advancements in different nanocarriers for breast cancer chemotherapy. It also delves into the associated hurdles and offers valuable insights into the prospective directions for this innovative field.

Anti-proliferation evaluation of new derivatives of indole-6-carboxylate ester as receptor tyrosine kinase inhibitors

Aim: The main goal was to create two new groups of indole derivatives, hydrazine-1-carbothioamide (4a and 4b) and oxadiazole (5, and 6a-e) that target EGFR (4a, 4b, 5) or VEGFR-2 (6a-e). Materials & methods: The new derivatives were characterized using various spectroscopic techniques. Docking studies were used to investigate the binding patterns to EGFR/VEGFR-2, and the anti-proliferative properties were tested in vitro. Results: Compounds 4a (targeting EGFR) and 6c (targeting VEGFR-2) were the most effective cytotoxic agents, arresting cancer cells in the G2/M phase and inducing the extrinsic apoptosis pathway. Conclusion: The results of this study show that compounds 4a and 6c are promising cytotoxic compounds that inhibit the tyrosine kinase activity of EGFR and VEGFR-2, respectively.

Spatial multimodal analysis of transcriptomes and metabolomes in tissues

We present a spatial omics approach that combines histology, mass spectrometry imaging and spatial transcriptomics to facilitate precise measurements of mRNA transcripts and low-molecular-weight metabolites across tissue regions. The workflow is compatible with commercially available Visium glass slides. We demonstrate the potential of our method using mouse and human brain samples in the context of dopamine and Parkinson's disease.

Matairesinoside, a novel inhibitor of TMEM16A ion channel, loaded with functional hydrogel for lung cancer treatment

The incidence and mortality rates of lung cancer have remained high for several decades, necessitating the discovery of new drugs and the development of effective treatment strategies. This study identified matairesinoside (MTS) as a potent inhibitor of TMEM16A, a novel drug target for lung cancer. Molecular simulation combined with site-directed mutagenesis experiments confirmed the key binding sites of MTS and TMEM16A. Cell experiments demonstrated that MTS significantly inhibited the growth, migration, and invasion of lung cancer cells, while inducing apoptosis. Gene knockdown and overexpression studies further revealed that TMEM16A is the target for MTS in regulating lung cancer cell growth. Western blot analysis elucidated the signaling transduction network involved in MTS-mediated regulation of lung cancer. Building upon these findings, a biodegradable self-healing functional hydrogel was developed to load MTS, aiming to enhance therapeutic efficacy and minimize side effects in vivo. Animal experiments demonstrated that the hydrogel/MTS formulation exhibited satisfactory inhibitory effects on lung cancer and mitigated the side effects associated with direct MTS injection. This study identified MTS as a potential candidate for anti-lung cancer therapy with well-defined pharmacological mechanisms. Moreover, the targeted drug delivery system utilizing the hydrogel/MTS platform offers a promising approach for lung cancer treatment.

The therapeutic potential of natural metabolites in targeting endocrine-independent HER-2-negative breast cancer

Breast cancer (BC) is a heterogenous disease, with prognosis and treatment options depending on Estrogen, Progesterone receptor, and Human Epidermal Growth Factor Receptor-2 (HER-2) status. HER-2 negative, endocrine-independent BC presents a significant clinical challenge with limited treatment options. To date, promising strategies like immune checkpoint inhibitors have not yielded breakthroughs in patient prognosis. Despite being considered archaic, agents derived from natural sources, mainly plants, remain backbone of current treatment. In this context, we critically analyze novel naturally-derived drug candidates, elucidate their intricate mechanisms of action, and evaluate their pre-clinical in vitro and in vivo activity in endocrine-independent HER-2 negative BC. Since pre-clinical research success often does not directly correlate with drug approval, we focus on ongoing clinical trials to uncover current trends. Finally, we demonstrate the potential of combining cutting-edge technologies, such as antibody-drug conjugates or nanomedicine, with naturally-derived agents, offering new opportunities that utilize both traditional cytotoxic agents and new metabolites.

tRNA-derived fragments: Key determinants of cancer metastasis with emerging therapeutic and diagnostic potentials

Metastasis is a significant clinical challenge responsible for cancer mortality and non-response to treatment. However, the molecular mechanisms driving metastasis remain unclear, limiting the development of efficient diagnostic and therapeutic approaches. Recent breakthroughs in cancer biology have discovered a group of small non-coding RNAs called tRNA-derived fragments (tRFs), which play a critical role in the metastatic behavior of various tumors. tRFs are produced from cleavage modifications of tRNAs and have different functional classes based on the pattern of these modifications. They perform post-transcriptional regulation through microRNA-like functions, displacing RNA-binding proteins, and play a role in translational regulation by inducing ribosome synthesis, translation initiation, and epigenetic regulation. Tumor cells manipulate tRFs to develop and survive the tumor mass, primarily by inducing metastasis. Multiple studies have demonstrated the potential of tRFs as therapeutic, diagnostic, and prognostic targets for tumor metastasis. This review discusses the production and function of tRFs in cells, their aberrant molecular contributions to the metastatic environment, and their potential as promising targets for anti-metastasis treatment strategies.

A combined approach of structure-based virtual screening and NMR to interrupt the PD-1/PD-L1 axis: Biphenyl-benzimidazole containing compounds as novel PD-L1 inhibitors

Immunotherapy has emerged as a game-changing approach for cancer treatment. Although monoclonal antibodies (mAbs) targeting the programmed cell death protein 1/programmed cell death protein 1 ligand 1 (PD-1/PD-L1) axis have entered the market revolutionizing the treatment landscape of many cancer types, small molecules, although presenting several advantages including the possibility of oral administration and/or reduced costs, struggled to enter in clinical trials, suffering of water insolubility and/or inadequate potency compared with mAbs. Thus, the search for novel scaffolds for both the design of effective small molecules and possible synergistic strategies is an ongoing field of interest. In an attempt to find novel chemotypes, a virtual screening approach was employed, resulting in the identification of new chemical entities with a certain binding capability, the most versatile of which was the benzimidazole-containing compound 10. Through rational design, a small library of its derivatives was synthesized and evaluated. The homogeneous time-resolved fluorescence (HTRF) assay revealed that compound 17 shows the most potent inhibitory activity (IC50 ) in the submicromolar range and notably, differently from the major part of PD-L1 inhibitors, exhibits satisfactory water solubility properties. These findings highlight the potential of benzimidazole-based compounds as novel promising candidates for PD-L1 inhibition.

Cellaca® PLX image cytometer as an alternative for immunophenotyping, GFP/RFP transfection efficiencies, and apoptosis analysis

Cell and gene therapy is a fast-growing field for cancer therapeutics requiring reliable instrumentation and technologies. Key parameters essential for satisfying Chemistry Manufacturing and Controls criteria standards are routinely performed using flow cytometry. Recently, image cytometry was developed for cell characterization and cell-based assays but had not yet demonstrated sufficient sensitivity for surface marker detection. We developed the Cellaca® PLX image cytometry system and the respective methodologies required for immunophenotyping, GFP and RFP transfection/transduction efficiencies, and cell health analyses for routine cell characterization. All samples tested were compared directly to results from the CytoFLEX flow cytometer. PBMCs were stained with T-cell surface markers for immunophenotyping, and results show highly comparable CD3, CD4, and CD8 populations (within 5 %). GFP- or RFP-expressing cell lines were analyzed for transfection/transduction efficiencies, and the percentage positive cells and respective viabilities were equivalent on both systems. Staurosporine-treated Jurkat cells were stained for apoptotic markers, where annexin V and caspase-3 positive cells were within 5 % comparing both instruments. The proposed system may provide a complementary tool for performing routine cell-based experiments with improved efficiency and sensitivity compared to prior image cytometers, which may be significantly valuable to the cell and gene therapy field.

Solubilizer Tag Effect on PD-L1/Inhibitor Binding Properties for m-Terphenyl Derivatives

Although heavily studied, the subject of anti-PD-L1 small-molecule inhibitors is still elusive. Here we present a systematic overview of the principles behind successful anti-PD-L1 small-molecule inhibitor design on the example of the m-terphenyl scaffold, with a particular focus on the neglected influence of the solubilizer tag on the overall affinity toward PD-L1. The inhibitor developed according to the proposed guidelines was characterized through its potency in blocking PD-1/PD-L1 complex formation in homogeneous time-resolved fluorescence and cell-based assays. The affinity is also explained based on the crystal structure of the inhibitor itself and its costructure with PD-L1 as well as a molecular modeling study. Our results structuralize the knowledge related to the strong pharmacophore feature of the m-terphenyl scaffold preferential geometry and the more complex role of the solubilizer tag in PD-L1 homodimer stabilization.

Strategic and Innovative Roles of lncRNAs Regulated by Naturally-derived Small Molecules in Cancer Therapy

In the field of precision and personalized medicine, the next generation sequencing method has begun to take an active place as genome-wide screening applications in the diagnosis and treatment of diseases. Studies based on the determination of the therapeutic efficacy of personalized drug use in cancer treatment in the size of the transcriptome and its extension, lncRNA, have been increasing rapidly in recent years. Targeting and/or regulating noncoding RNAs (ncRNAs) consisting of long noncoding RNAs (lncRNAs) are promising strategies for cancer treatment. Within the scope of rapidly increasing studies in recent years, it has been shown that many natural agents obtained from biological organisms can potentially alter the expression of many lncRNAs associated with oncogenic functions. Natural agents include effective small molecules that provide anti-cancer effects and have been used as chemotherapy drugs or in combination with standard anti-cancer drugs used in routine treatment. In this review, it was aimed to provide detailed information about the potential of natural agents to regulate and/or target non-coding RNAs and their mechanisms of action to provide an approach for cancer therapy. The discovery of novel anti-cancer targets and subsequent development of effective drugs or combination strategies that are still needed for most cancers will be promising for cancer treatment.

Improving targeted small molecule drugs to overcome chemotherapy resistance

BACKGROUND

Conventional cancer treatments face the challenge of therapeutic resistance, which causes poor treatment outcomes. The use of combination therapies can improve treatment results in patients and is one of the solutions to overcome this challenge. Chemotherapy is one of the conventional treatments that, due to the non-targeted and lack of specificity in targeting cancer cells, can cause serious complications in the short and long-term for patients by damaging healthy cells. Also, the employment of a wide range of strategies for chemotherapy resistance by cancer cells, metastasis, and cancer recurrence create serious problems to achieve the desired results of chemotherapy. Accordingly, targeted therapies can be used as a combination treatment with chemotherapy to both cause less damage to healthy cells, which as a result, they reduce the side effects of chemotherapy, and by targeting the factors that cause therapeutic challenges, can improve the results of chemotherapy in patients.

RECENT FINDINGS

Small molecules are one of the main targeted therapies that can be used for diverse targets in cancer treatment due to their penetration ability and characteristics. However, small molecules in cancer treatment are facing obstacles that a better understanding of cancer biology, as well as the mechanisms and factors involved in chemotherapy resistance, can lead to the improvement of this type of major targeted therapy.

CONCLUSION

In this review article, at first, the challenges that lead to not achieving the desired results in chemotherapy and how cancer cells can be resistant to chemotherapy are examined, and at the end, research areas are suggested that more focusing on them, can lead to the improvement of the results of using targeted small molecules as an adjunctive treatment for chemotherapy in the conditions of chemotherapy resistance and metastasis of cancer cells.

Sonosensitive Cavitation Nuclei-A Customisable Platform Technology for Enhanced Therapeutic Delivery

Ultrasound-mediated cavitation shows great promise for improving targeted drug delivery across a range of clinical applications. Cavitation nuclei-sound-sensitive constructs that enhance cavitation activity at lower pressures-have become a powerful adjuvant to ultrasound-based treatments, and more recently emerged as a drug delivery vehicle in their own right. The unique combination of physical, biological, and chemical effects that occur around these structures, as well as their varied compositions and morphologies, make cavitation nuclei an attractive platform for creating delivery systems tuned to particular therapeutics. In this review, we describe the structure and function of cavitation nuclei, approaches to their functionalization and customization, various clinical applications, progress toward real-world translation, and future directions for the field.

Targeting Breast Cancer Signaling via Phytomedicine and Nanomedicine

BACKGROUND

The development of breast cancer (BC) and how it responds to treatment have both been linked to the involvement of inflammation. Chronic inflammation is critical in carcinogenesis, leading to elevated DNA damage, impaired DNA repair machinery, cell growth, apoptosis, angiogenesis, and invasion. Studies have found several targets that selectively modulate inflammation in cancer, limit BC's growth, and boost treatment effectiveness. Drug resistance and the absence of efficient therapeutics for metastatic and triple-negative BC contribute to the poor outlook of BC patients.

SUMMARY

To treat BC, small-molecule inhibitors, phytomedicines, and nanoparticles are conjugated to attenuate BC signaling pathways. Due to their numerous target mechanisms and strong safety records, phytomedicines and nanomedicines have received much attention in studies examining their prospects as anti-BC agents by such unfulfilled demands.

KEY MESSAGES

The processes involved in the affiliation across the progression of tumors and the spread of inflammation are highlighted in this review. Furthermore, we included many drugs now undergoing clinical trials that target cancer-mediated inflammatory pathways, cutting-edge nanotechnology-derived delivery systems, and a variety of phytomedicines that presently address BC.

Comparison of the Effects of DOTA and NOTA Chelators on 64Cu-Cudotadipep and 64Cu-Cunotadipep for Prostate Cancer

BACKGROUND

This study compared the effects of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) as 64Cu-chelating agents in newly developed prostate-specific membrane antigen (PSMA) target compounds, 64Cu-cudotadipep and 64Cu-cunotadipep, on pharmacokinetics.

METHODS

The in vitro stability of the chelators was evaluated using human and mouse serum. In vitro PSMA-binding affinity and cell uptake were compared using human 22Rv1 cells. To evaluate specific PSMA-expressing tumor-targeting efficiency, micro-positron emission tomography (mcroPET)/computed tomography (CT) and biodistribution analysis were performed using PSMA+ PC3-PIP and PSMA- PC3-flu tumor xenografts.

RESULTS

The serum stability of DOTA- or NOTA-conjugated 64Cu-cudotadipep and 64Cu-cunotadipep was >97%. The Ki value of the NOTA derivative, cunotadipep, in the in vitro affinity binding analysis was higher (2.17 ± 0.25 nM) than that of the DOTA derivative, cudotadipep (6.75 ± 0.42 nM). The cunotadipep exhibited a higher cellular uptake (6.02 ± 0.05%/1 × 106 cells) compared with the cudotadipep (2.93 ± 0.06%/1 × 106 cells). In the biodistribution analysis and microPET/CT imaging, the 64Cu-labeled NOTA derivative, 64Cu-cunotadipep, demonstrated a greater tumor uptake and lower liver uptake than the DOTA derivative.

CONCLUSIONS

This study indicates that the PSMA-targeted 64Cu-cunotadipep can be applied in clinical practice owing to its high diagnostic power for prostate cancer.

The role of chromatin remodeler SMARCA4/BRG1 in brain cancers: a potential therapeutic target

The chromatin remodeler SMARCA4/BRG1 is a key epigenetic regulator with diverse roles in coordinating the molecular programs that underlie brain tumour development. BRG1 function in brain cancer is largely specific to the tumour type and varies further between tumour subtypes, highlighting its complexity. Altered SMARCA4 expression has been linked to medulloblastoma, low-grade gliomas such as oligodendroglioma, high-grade gliomas such as glioblastoma and atypical/teratoid rhabdoid tumours. SMARCA4 mutations in brain cancer predominantly occur in the crucial catalytic ATPase domain, which is associated with tumour suppressor activity. However, SMARCA4 is opposingly seen to promote tumourigenesis in the absence of mutation and through overexpression in other brain tumours. This review explores the multifaceted interaction between SMARCA4 and various brain cancer types, highlighting its roles in tumour pathogenesis, the pathways it regulates, and the advances that have been made in understanding the functional relevance of mutations. We discuss developments made in targeting SMARCA4 and the potential to translate these to adjuvant therapies able to enhance current methods of brain cancer treatment.

Cancer chemotherapy and beyond: Current status, drug candidates, associated risks and progress in targeted therapeutics

Cancer is an abnormal state of cells where they undergo uncontrolled proliferation and produce aggressive malignancies that causes millions of deaths every year. With the new understanding of the molecular mechanism(s) of disease progression, our knowledge about the disease is snowballing, leading to the evolution of many new therapeutic regimes and their successive trials. In the past few decades, various combinations of therapies have been proposed and are presently employed in the treatment of diverse cancers. Targeted drug therapy, immunotherapy, and personalized medicines are now largely being employed, which were not common a few years back. The field of cancer discoveries and therapeutics are evolving fast as cancer type-specific biomarkers are progressively being identified and several types of cancers are nowadays undergoing systematic therapies, extending patients' disease-free survival thereafter. Although growing evidence shows that a systematic and targeted approach could be the future of cancer medicine, chemotherapy remains a largely opted therapeutic option despite its known side effects on the patient's physical and psychological health. Chemotherapeutic agents/pharmaceuticals served a great purpose over the past few decades and have remained the frontline choice for advanced-stage malignancies where surgery and/or radiation therapy cannot be prescribed due to specific reasons. The present report succinctly reviews the existing and contemporary advancements in chemotherapy and assesses the status of the enrolled drugs/pharmaceuticals; it also comprehensively discusses the emerging role of specific/targeted therapeutic strategies that are presently being employed to achieve better clinical success/survival rate in cancer patients.

Not all benzimidazole derivatives are microtubule destabilizing agents

In recent years, microtubule-targeting agents (MTAs) have gained considerable interest in developing novel small-molecule anticancer drugs. MTAs demonstrate anticancer activity either as microtubule-stabilizing agents (paclitaxel) or microtubule-destabilizing agents (nocodazole). FDA-approved drugs containing a benzimidazole ring (nocodazole, albendazole, mebendazole, etc.) are well-known microtubule-destabilizing agents. Thus, most recent research on benzimidazole scaffold-based MTAs focuses on developing microtubule-destabilizing agents. However, there is no report on the benzimidazole scaffold-based microtubule-stabilizing agent. Here, we present the benzimidazole derivatives NI-11 and NI-18 that showed a profound anticancer activity as microtubule-stabilization agents. About twenty benzimidazole analogues were synthesized with excellent yield (80.0% ∼ 98.0%) and tested for their anticancer activity using two cancer cell lines (A549, MCF-7) and one normal cell line (MRC-5). NI-11 showed IC₅₀ values of 2.90, 7.17, and 16.9 µM in A549, MCF-7, and MRC-5 cell lines. NI-18 showed IC₅₀ values of 2.33, 6.10, and 12.1 µM in A549, MCF-7, and MRC-5 cell lines. Thus, NI-11 and NI-18 demonstrated selectivity indexes of 5.81 and 5.20, respectively, which are much higher than the currently available anticancer agents. NI-11 and NI-18 inhibited the cancer cell motility and migration, induced the early phase apoptosis. Both of these comounds were found to show an upregulation of DeY-α-tubulin and downregulation of Ac-α-tubulin expressions in cancer cells. Eventhough the reported benzimidazole scaffold-based commercially available drugs are known to be microtubule-destabilizing agents, the analogues NI-11 and NI-18 were found to have microtubule-stabilizing activity. The in vitro tubulin polymerization assay and the immunofluorescence assay results indicate that the NI-11 and NI-18 exhibit anticancer activity by stabilizing the microtubule network.

Dietary Oncopharmacognosy as a Crosswalk between Precision Oncology and Precision Nutrition

While diet and nutrition are modifiable risk factors for many chronic and infectious diseases, their role in cancer prevention and control remains under investigation. The lack of clarity of some diet-cancer relationships reflects the ongoing debate about the relative contribution of genetic factors, environmental exposures, and replicative errors in stem cell division as determinate drivers of cancer risk. In addition, dietary guidance has often been based upon research assuming that the effects of diet and nutrition on carcinogenesis would be uniform across populations and for various tumor types arising in a specific organ, i.e., that one size fits all. Herein, we present a paradigm for investigating precision dietary patterns that leverages the approaches that led to successful small-molecule inhibitors in cancer treatment, namely understanding the pharmacokinetics and pharmacodynamics of small molecules for targeting carcinogenic mechanisms. We challenge the scientific community to refine the paradigm presented and to conduct proof-in-concept experiments that integrate existing knowledge (drug development, natural products, and the food metabolome) with developments in artificial intelligence to design and then test dietary patterns predicted to elicit drug-like effects on target tissues for cancer prevention and control. We refer to this precision approach as dietary oncopharmacognosy and envision it as the crosswalk between the currently defined fields of precision oncology and precision nutrition with the goal of reducing cancer deaths.

Therapeutic potential of tumor treating fields for malignant brain tumors

BACKGROUND

Malignant brain tumors are among the most threatening diseases of the central nervous system, and despite increasingly updated treatments, the prognosis has not been improved. Tumor treating fields (TTFields) are an emerging approach in cancer treatment using intermediate-frequency and low-intensity electric field and can lead to the development of novel therapeutic options.

RECENT FINDINGS

A series of biological processes induced by TTFields to exert anti-cancer effects have been identified. Recent studies have shown that TTFields can alter the bioelectrical state of macromolecules and organelles involved in cancer biology. Massive alterations in cancer cell proteomics and transcriptomics caused by TTFields were related to cell biological processes as well as multiple organelle structures and activities. This review addresses the mechanisms of TTFields and recent advances in the application of TTFields therapy in malignant brain tumors, especially in glioblastoma (GBM).

CONCLUSIONS

As a novel therapeutic strategy, TTFields have shown promising results in many clinical trials, especially in GBM, and continue to evolve. A growing number of patients with malignant brain tumors are being enrolled in ongoing clinical studies demonstrating that TTFields-based combination therapies can improve treatment outcomes.

Drug Delivery Systems for Localized Cancer Combination Therapy

With over 2 million cancer cases and over 600,000 cancer-associated deaths predicted in the U.S. for 2022, this life-debilitating disease continuously impacts the lives of people across the nation every day. Therapeutic treatment options for cancer have historically involved chemotherapies to eradicate tumors with cytotoxic mechanisms which can negatively affect the efficacy versus toxicity ratio of treatment. With a need for more directed and therapeutically active options, targeted small-molecule inhibitors and immunotherapies have since emerged to mitigate treatment-associated toxicities. However, aggressive tumors can employ a wide range of defense mechanisms to evade monotherapy treatment altogether, resulting in the recurrence of therapeutically resistant tumors. Therefore, many clinical routines have included combination therapy in which anticancer agents are combined to provide a synergistic attack on tumors. Even with this approach, maximizing the efficacy of cancer treatment is contingent upon the dose of drug that reaches the site of the tumor, so often therapy is administered at the site of a tumor via localized delivery platforms. Commonly used platforms for localized drug delivery include polymeric wafers, nanofibrous scaffolds, and hydrogels where drug combinations can be loaded and delivered synchronously. Attaining synergistic activity from these localized systems is dependent on proper material selection and fabrication methods. Herein, we describe these important considerations for enhancing the efficacy of cancer combination therapy through biodegradable, localized delivery systems.

Quiescent Cancer Cells-A Potential Therapeutic Target to Overcome Tumor Resistance and Relapse

Quiescent cancer cells (QCCs) are nonproliferating cells arrested in the G0 phase, characterized by ki67^low and p27^high. QCCs avoid most chemotherapies, and some treatments could further lead to a higher proportion of QCCs in tumors. QCCs are also associated with cancer recurrence since they can re-enter a proliferative state when conditions are favorable. As QCCs lead to drug resistance and tumor recurrence, there is a great need to understand the characteristics of QCCs, decipher the mechanisms that regulate the proliferative-quiescent transition in cancer cells, and develop new strategies to eliminate QCCs residing in solid tumors. In this review, we discussed the mechanisms of QCC-induced drug resistance and tumor recurrence. We also discussed therapeutic strategies to overcome resistance and relapse by targeting QCCs, including (i) identifying reactive quiescent cancer cells and removing them via cell-cycle-dependent anticancer reagents; (ii) modulating the quiescence-to-proliferation switch; and (iii) eliminating QCCs by targeting their unique features. It is believed that the simultaneous co-targeting of proliferating and quiescent cancer cells may ultimately lead to the development of more effective therapeutic strategies for the treatment of solid tumors.

Targeted Lymphoma Therapy Using a Gold Nanoframework-Based Drug Delivery System

Precision nanomedicine can be employed as an alternative to chemo- or radiotherapy to overcome challenges associated with the often narrow therapeutic window of traditional treatment approaches, while safely inducing effective, targeted antitumor responses. Herein, we report the formulation of a therapeutic nanocomposite comprising a hyaluronic acid (HA)-coated gold nanoframework (AuNF) delivery system and encapsulated IT848, a small molecule with potent antilymphoma and -myeloma properties that targets the transcriptional activity of nuclear factor kappa B (NF-κB). The porous AuNFs fabricated via a liposome-templated approach were loaded with IT848 and surface-functionalized with HA to formulate the nanotherapeutics that were able to efficiently deliver the payload with high specificity to myeloma and lymphoma cell lines in vitro. In vivo studies characterized biodistribution, pharmacokinetics, and safety of HA-AuNFs, and we demonstrated superior efficacy of HA-AuNF-formulated IT848 vs free IT848 in lymphoma mouse models. Both in vitro and in vivo results affirm that the AuNF system can be adopted for targeted cancer therapy, improving the drug safety profile, and enhancing its efficacy with minimal dosing. HA-AuNF-formulated IT848 therefore has strong potential for clinical translation.

Prospective role of PD-1/PD-L1 immune checkpoint inhibitors in GI cancer

One of the mechanisms by which tumor cells can evade the immune system is over activation of the programmed cell death protein-1 (PD-1) / programmed death-ligand 1 (PD-L1) pathway. The binding of PD-1 to its ligand PD-L1 can trigger an inhibitory signal for reducing T-cell proliferation, inhibiting the anticancer effect of T cells, and limiting the anti-tumor immunity of effectors T cell responses to protect tissues from immune-mediated tissue damage in the tumor microenvironment (TME). PD-1/PD-L1 immune checkpoint inhibitors have created a new pattern in cancer immunotherapy and can increase T cell- surveillance; therefore, the development of better clinical application of PD-1/PD-L1 inhibitors can significantly enhance antitumor immunity and prolong survival in GI cancer patients.

A potent bioactive fraction against colon cancer from Plectranthus vettiveroides

Aim

This study was designed to investigate the anticancer efficacy of the organic leaf extracts of the plant, Plectranthus vettiveroides (P. vettiveroides), and to analyze the molecular mechanism of the anticancer activity.

Methods

The leaf extracts were prepared by polarity-graded serial extraction of the dried leaf powder. The cytotoxic effect of the extracts was analyzed by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The most active ethyl acetate extract was subjected to bioactivity-guided fractionation by column chromatography, which yielded a cytotoxic fraction designated as the P. vettiveroides fraction (PVF). The anticancer property of PVF was confirmed further by clonogenic assay. The mechanism of PVF-induced cell death was analyzed by flow cytometry and fluorescence microscopy. Additionally, the effects of PVF on apoptotic and cell survival pathways were analyzed using western immunoblot analysis.

Results

A bioactive fraction PVF, was isolated from the ethyl acetate leaf extract. PVF showed significant anticancer activity against colon cancer cells, whilst normal cells were comparatively less affected. PVF induced strong apoptotic stimuli in colorectal carcinoma cell line HCT116, involving both extrinsic and intrinsic pathways. Investigation into the molecular mechanism of anticancer activity of PVF in HCT116 cells revealed that the fraction activates the pro-apoptotic pathway via tumor suppressor protein 53 (p53) and inhibits the anti-apoptotic pathway by regulating phosphatidylinositol 3-kinase (PI3K) signaling.

Conclusions

The findings of this study demonstrate, with mechanism-based evidence, the chemotherapeutic potential of a bioactive fraction PVF, derived from the leaves of the medicinal plant P. vettiveroides against colon cancer.

Pharmacomicrobiomics in Anticancer Therapies: Why the Gut Microbiota Should Be Pointed Out

Anticancer treatments have shown a variable therapeutic outcome that may be partly attributable to the activity of the gut microbiota on the pathology and/or therapies. In recent years, microbiota-drug interactions have been extensively investigated, but most of the underlying molecular mechanisms still remain unclear. In this review, we discuss the relationship between the gut microbiota and some of the most commonly used drugs in oncological diseases. Different strategies for manipulating the gut microbiota layout (i.e., prebiotics, probiotics, antibiotics, and fecal microbiota transplantation) are then explored in order to optimize clinical outcomes in cancer patients. Anticancer technologies that exploit tumor-associated bacteria to target tumors and biotransform drugs are also briefly discussed. In the field of pharmacomicrobiomics, multi-omics strategies coupled with machine and deep learning are urgently needed to bring to light the interaction among gut microbiota, drugs, and host for the development of truly personalized precision therapies.

LC-MS/MS-Based Metabolomic Profiling of Constituents from Glochidion velutinum and Its Activity against Cancer Cell Lines

This study aimed to establish the phytochemical profile of Glochidion velutinum and its cytotoxic activity against prostate cancer (PC-3) and breast cancer (MCF-7) cell lines. The phytochemical composition of G. velutinum leaf extract and its fractions was established with the help of total phenolic and flavonoid contents and LC-MS/MS-based metabolomics analysis. The crude methanolic extract and its fractions were studied for pharmacological activity against PC-3 and MCF-7 cell lines using the MTT assay. The total phenolic content of the crude extract and its fractions ranged from 44 to 859 µg GAE/mg of sample whereas total flavonoid contents ranged from 20 to 315 µg QE/mg of sample. A total of forty-eight compounds were tentatively dereplicated in the extract and its fractions. These phytochemicals included benzoic acid derivatives, flavans, flavones, O-methylated flavonoids, flavonoid O- and C-glycosides, pyranocoumarins, hydrolysable tannins, carbohydrate conjugates, fatty acids, coumarin glycosides, monoterpenoids, diterpenoids, and terpene glycosides. The crude extract (IC50 = 89 µg/mL), the chloroform fraction (IC50 = 27 µg/mL), and the water fraction (IC50 = 36 µg/mL) were found to be active against the PC-3 cell line. However, the crude extract (IC50 = 431 µg/mL), the chloroform fraction (IC50 = 222 µg/mL), and the ethyl acetate fraction (IC50 = 226 µg/mL) have shown prominent activity against breast cancer cells. Moreover, G. velutinum extract and its fractions presented negligible toxicity to normal macrophages at the maximum tested dose (600 µg/mL). Among the compounds identified through LC-MS/MS-based metabolomics analysis, epigallocatechin gallate, ellagic acid, isovitexin, and rutin were reported to have anticancer activity against both prostate and breast cancer cell lines and might be responsible for the cytotoxic activities of G. velutinum extract and its bioactive fractions.

The emerging role of radical chemistry in the amination transformation of highly strained [1.1.1]propellane: Bicyclo[1.1.1]pentylamine as bioisosteres of anilines

Bicyclo[1.1.1]pentylamines (BPCAs), emerging as sp3-rich surrogates for aniline and its derivatives, demonstrate unique structural features and physicochemical profiles in medicinal and synthetic chemistry. In recent years, compared with conventional synthetic approaches, the rapid development of radical chemistry enables the assembly of valuable bicyclo[1.1.1]pentylamines scaffold directly through the amination transformation of highly strained [1.1.1]propellane. In this review, we concisely summarize the emerging role of radical chemistry in the construction of BCPAs motif, highlighting two different and powerful radical-involved strategies including C-centered and N-centered radical pathways under appropriate conditions. The future direction concerning BCPAs is also discussed at the end of this review, which aims to provide some inspiration for the research of this promising project.

Improving cancer immunotherapy by rationally combining oncolytic virus with modulators targeting key signaling pathways

Oncolytic viruses (OVs) represent a new class of multi-modal immunotherapies for cancer, with OV-elicited antitumor immunity being key to their overall therapeutic efficacy. Currently, the clinical effectiveness of OV as monotherapy remains limited, and thus investigators have been exploring various combinations with other anti-cancer agents and demonstrated improved therapeutic efficacy. As cancer cells have evolved to alter key signaling pathways for enhanced cell proliferation, cancer progression and metastasis, these cellular and molecular changes offer promising targets for rational cancer therapy design. In this regard, key molecules in relevant signaling pathways for cancer cells or/and immune cells, such as EGFR-KRAS (e.g., KRAS^G12C), PI3K-AKT-mTOR, ERK-MEK, JAK-STAT, p53, PD-1-PD-L1, and epigenetic, or immune pathways (e.g., histone deacetylases, cGAS-STING) are currently under investigation and have the potential to synergize with OV to modulate the immune milieu of the tumor microenvironment (TME), thereby improving and sustaining antitumor immunity. As many small molecule modulators of these signaling pathways have been developed and have shown strong therapeutic potential, here we review key findings related to both OV-mediated immunotherapy and the utility of small molecule modulators of signaling pathways in immuno-oncology. Then, we focus on discussion of the rationales and potential strategies for combining OV with selected modulators targeting key cellular signaling pathways in cancer or/and immune cells to modulate the TME and enhance antitumor immunity and therapeutic efficacy. Finally, we provide perspectives and viewpoints on the application of novel experimental systems and technologies that can propel this exciting branch of medicine into a bright future.