Immune checkpoint blockade therapy has revolutionized cancer treatment, yet its clinical efficacy remains limited to a subset of patients with specific tumor types. The present review provides a comprehensive analysis of T cell‑mediated antitumor immunity from both local and systemic perspectives, with particular emphasis on CD8+ T cells as primary effectors. The review discusses how the complex trafficking between the tumor microenvironment (TME), surrounding lymphoid tissues and peripheral circulation creates multiple opportunities for tumors to evade immune surveillance. Within the TME, T‑cell exclusion mechanisms, antigen specificity and the spectrum of T‑cell exhaustion states, from progenitor exhausted T cells to terminally exhausted T‑cell phenotypes, are reviewed. Beyond the local TME, the crucial roles of tumor‑draining lymph nodes and tertiary lymphoid structures in maintaining sustainable antitumor immunity, as well as the significance of circulating T cells as both biomarkers and therapeutic targets, are analyzed. This systemic perspective provides insights into the dynamic nature of antitumor immunity and suggests potential strategies for next‑generation immunotherapies, including combination approaches targeting multiple immune compartments to achieve optimal therapeutic outcomes.

Triple‑negative breast cancer (TNBC) is a lethal subtype of breast cancer with a poor prognosis and limited existing treatment options. The immune checkpoint inhibitor, anti‑programmed death ligand 1 (PD‑L1), has recently emerged as a promising alternative in treating TNBC. PD‑L1 is critical in tumor immune evasion and is therefore a key target for cancer immunotherapy. Although anti‑PD‑L1 therapy is effective in breast cancer based on clinical trials, the relationship between PD‑L1 expression levels and treatment response remains unclear. To investigate this, a 4T1 breast cancer cell line that stably overexpressed PD‑L1 was established and was used to create a tumor model in mice. Mice were treated with anti‑PD‑L1 antibodies, and tumor growth was compared between the control and treated groups. PD‑L1 overexpressing tumors did not exhibit an antitumor response to anti‑PD‑L1 therapy compared with the control tumors. Additionally, immune cell infiltration and activation were significantly altered, as shown by immunohistochemical staining and bulk RNA sequencing. In PD‑L1‑overexpressing tumors that did not respond to treatment, immune cell markers and antitumor immune pathways were downregulated. These results demonstrated that excessive PD‑L1 expression creates an immunosuppressive tumor microenvironment, which impairs the efficacy of anti‑PD‑L1 therapy. The present study suggests that excessive PD‑L1 expression reduces the effectiveness of antitumor immunotherapy, and that PD‑L 1 expression levels are essential in predicting the response to antitumor immunotherapy.

Acute myeloid leukemia (AML), originating from myeloid hematopoietic stem/progenitor cells, is a malignant hematological disorder. Resistance to current treatments, especially in FLT3-ITD AML cases, urgently demands the development of novel therapeutics. In this study, we pinpointed fostamatinib, an orally delivered small molecule SYK inhibitor for chronic immune thrombocytopenia (ITP), as a promising candidate for drug repurposing. It effectively inhibited FLT3-ITD+ AML cell proliferation and induced leukemic cell apoptosis. Network pharmacology analysis further deciphered the associated pharmacological mechanism related to the PI3K-AKT signaling pathway. Moreover, fostamatinib downregulated the expression of immune checkpoints such as PD-L1 and CD47. Overall, this study provided a conceptual foundation for evaluating the advantages of drug repurposing in AML drug development.

The efficacy of regorafenib or fruquintinib in combination with PD-1/PD-L1 inhibitors for metastatic colorectal cancer (mCRC) treatment has not been elucidated. This study aims to systematically evaluate the efficacy and safety of this combination therapy.

Canine oral papillomatosis, caused by canine papilloma virus 1, is a benign condition primarily affecting young or immunosuppressed dogs. While most cases regress spontaneously, severe cases often require surgical intervention due to extensive lesions and associated discomforts. However, surgical excision is associated with a high risk of recurrence, necessitating adjuvant therapies. This report presents the case of a 1-year-old German Shepherd with severe oral papilloma unresponsive to prior treatments, managed through surgical excision followed by topical mitomycin C (MMC) application. MMC, applied intraoperatively and during follow-up, effectively prevented recurrence over a 1-year period. This case demonstrates the potential of MMC as an effective adjuvant therapy for severe canine oral papillomatosis, providing a novel approach in veterinary medicine.

Withanolides are a class of naturally occurring C-28 ergostane steroidal lactones with an abundance of biological activities, and their members are promising candidates for antineoplastic drug development. The ADMET properties of withanolides are still largely unknown, and in silico predictions can play a crucial role highlighting these characteristics for drug development, shortening time and resources spent on the development of a drug lead. In this work, ADMET properties of promising antitumoral withanolides were assessed. Each chemical structure was submitted to the prediction tools: SwissADME, pkCSM-pharmacokinetics, admetSAR v2.0, and Molinspiration Cheminformatics. The results indicate a good gastrointestinal absorption rate, inability to cross the blood-brain barrier, CYP3A4 metabolization, without inhibition of other P450 cytochromes, high interaction with nuclear receptors, and a low toxicity. It was also predicted for the inhibition of pharmacokinetics transporters and some ecotoxicity. This demonstrates a viability for oral drug development, with low probabilities of side effects.

Aminosteroid derivative RM-581 stands out as an anticancer agent, supported by positive in vitro and in vivo studies on resistant cancers of the breast, prostate, and pancreas. A synthetic route has already been developed to obtain aminosteroid RM-581 in small quantities (scale of milligrams to a few grams). However, this route has significant limitations in view of its transposition to scaling up to larger quantities to support late preclinical and clinical trials. Among the problems are the use of toxic reagents, the moderate overall yield, and the need for multiple purifications through chromatographic columns. The development of a new synthetic route has therefore been explored. Starting from commercially available estrone, 2,4-dibromo-estrone was rapidly formed, followed by the regioselective introduction of a nitro group at the C2 position and by the methylation of phenol at the C3 position. The 4-bromo-2-nitro-3-O-methylestrone was then reduced to 2-amino-3-O-methylestrone and the primary amine was used to form the piperazine ring. Once the cyclization step was carried out, the last two steps were identical to the first synthetic route previously reported, i.e., introducing an ethynyl group at the C-17α position and then adding the quinoline-proline side chain with an N-acylation, assisted by a peptide coupling reagent. Importantly, no purification by chromatography was necessary during the whole sequence of reactions and only a final silica gel filtration, followed by recrystallization, led to RM-581 at a very high level of purity. The structure was also fully characterized by 2D NMR analysis.

Colorectal cancer (CRC) remains a major global health challenge, necessitating the development of more effective and environmentally sustainable treatments. This study presents a novel green synthetic protocol for 1,3,5-triazine derivatives with anticancer potential, employing both microwave-assisted and ultrasound-assisted methods. The synthesis was optimized using 4-chloro-N-(2-chlorophenyl)-6-(morpholin-4-yl)-1,3,5-triazin-2-amine as the key intermediate, with sodium carbonate, TBAB, and DMF providing optimal yields under microwave conditions. To enhance sustainability, a modified sonochemical method was also developed, enabling efficient synthesis in aqueous media with a minimal use of organic solvents. A series of nine morpholine-functionalized derivatives were synthesized and evaluated for cytotoxic activity against SW480 and SW620 colorectal cancer cell lines. Compound 11 demonstrated superior antiproliferative activity (IC₅₀ = 5.85 µM) compared to the reference drug 5-fluorouracil, while compound 5 showed promising dual-line activity. In silico ADME analysis supported the drug likeness of the synthesized compounds, and biomimetic chromatography analysis confirmed favorable physicochemical properties, including lipophilicity and membrane affinity. These results underscore the potential of the developed protocol to produce bioactive triazine derivatives through an efficient, scalable, and environmentally friendly process, offering a valuable strategy for future anticancer drug development.

Cisplatin (CIS) is a widely used chemotherapeutic agent that is highly effective against various cancers. However, its clinical application is frequently limited by its substantial nephrotoxic side effects. The gastrin-releasing peptide receptor (GRPR), a critical regulator in inflammatory diseases, has been identified as a promising therapeutic target. Our previous studies have demonstrated that the GRPR antagonists PD176252 and RH-1402 can mitigate CIS-induced nephrotoxicity through anti-inflammatory mechanisms. Based on these findings, we designed and synthesized a series of 2-arylpropanoic acid-L-tryptophan derivatives to enhance the therapeutic effects. Among these compounds, 3m exhibited superior renal protection by significantly improving mouse renal tubular epithelial cell (mRTEC) viability from 50.2 ± 2.6% to 80.5 ± 3.9%, surpassing PD176252 (70.8 ± 1.4%) and RH-1402 (73.9 ± 3.7%). Moreover, compound 3m markedly reduced the expression of kidney injury molecule-1 (KIM-1) and inflammatory cytokines [Tumor Necrosis Factor-α (TNF-α), Interleukin-6 (IL-6), Monocyte Chemoattractant Protein-1 (MCP-1)]. Finally, molecular docking results revealed that 3m exhibited a high binding affinity for GRPR. Computational predictions using SwissADME further indicated that 3m possesses favorable drug-like properties, thereby supporting its potential as a promising candidate for mitigating CIS-induced nephrotoxicity.

Flavonoids and chalcones, widely recognised for their diverse biological activities, have garnered attention due to their potential therapeutic applications. This review discusses fluorinated flavonoids and chalcones, focusing on their prospective anti-inflammatory, antidiabetic, anticancer, antiosteoporotic, cardioprotective, neuroprotective, hepatoprotective, antimicrobial, and antiparasitic applications. The enhanced biological activities of fluorinated derivatives, particularly the antibacterial, antiviral, and anticancer properties, are attributed to the introduction of fluorine groups, which increase lipophilicity and metabolic stability. Key findings indicate that fluorinated flavonoids and chalcones exhibit synergistic effects with antibiotics, inhibit bacterial efflux pumps, and reveal potent antiviral and anticancer properties. However, challenges such as cytotoxicity and structural optimisation have to be addressed. The synthesis of fluorinated flavonoids and chalcones is discussed, with emphasis on various synthetic methods such as condensation and cyclisation reactions starting from fluorinated precursors, as well as fluorination strategies, including the use of molecular fluorine or fluorinating agents. Fluorinated flavonoids and chalcones represent candidates for therapeutic development and have the potential to overcome drug resistance. However, further studies are necessary to adjust their pharmacological profiles.

The Fabaceae family is known for the presence of isoflavones-phytoestrogens with potential chemopreventive effects against hormone-dependent cancers. This study aimed to optimize isoflavones extraction using a fractional factorial design and to quantitatively and qualitatively analyze 32 Fabaceae species native to Polish flora by HPLC-UV-VIS to indicate new, rich plant sources of isoflavones. The optimal extraction method was a 60 min reflux with 50% methanol and a plant material-to-solvent ratio of 1:125. The highest isoflavone levels were found in Trifolium medium (26.70 mg/g d.m.), Genista tinctoria (19.65 mg/g d.m.), and Trifolium pratense (12.56 mg/g d.m.). The obtained extracts were further evaluated for cytotoxic and antiproliferative activity against MCF7 and MDA-MB-231 human breast cancer cells. Genista tinctoria showed the highest cytotoxicity against MCF7, while Cytisus scoparius and Ononis arvensis were most effective against MDA-MB-231 at a dose of 500 µg/mL. The extracts were also characterized by varied, potent antioxidant properties, important in chemoprevention. A strong correlation was observed between isoflavone content and cytotoxic and antiproliferative activity exclusively in the estrogen receptor-positive MCF7 cell line. Importantly, the tested extracts demonstrated no toxic effects on normal human liver (HepG2), thyroid (Nthy-ori 3-1), or breast (MCF10A) cells, indicating a favorable safety profile.

Cervical cancer remains a major threat to women's health, with advanced cases often exhibiting recurrence and metastasis due to cancer stem cells driving therapy resistance. This study evaluated fenbendazole (FBZ), a repurposed veterinary anthelmintic, for its antitumor activity dual targeting cervical cancer cells (CCCs) and cervical cancer stem cells (CCSCs). CD133+CD44+ CCSCs were isolated from HeLa and C-33 A cell lines via immunomagnetic sorting and validated for stemness. Cell proliferation, cell cycle and apoptosis, and protein expression were detected by MST assay, flow cytometry, and Western blot analysis, respectively. FBZ dose-dependently inhibited proliferation, induced G2/M arrest, and triggered apoptosis in both CCCs and CCSCs. Mechanistically, FBZ upregulated cyclin B1 and phosphorylation of cdc25C-Ser198, while downregulating Wee1, phosphorylation of CDK1, and phosphorylation of cdc25C-Ser216, collectively enforcing G2/M blockade. In vivo, FBZ (100 mg/kg) significantly suppressed tumor growth in xenograft models without weight loss, contrasting with cisplatin-induced toxicity. Survival analysis revealed 100% survival in FBZ-treated mice versus 40% in cisplatin and 0% in untreated controls. These findings demonstrate FBZ's unique ability to simultaneously target bulk tumor cells and therapy-resistant CCSCs via cell cycle disruption, supported by its preclinical safety and efficacy, positioning it as a promising therapeutic candidate for cervical cancer.

Galaxamide, an N-methylated cyclo-pentapeptide containing five D-leucines isolated from Galaxaura filamentosa, has shown significant antitumor activity. This unique cyclo-pentapeptide offered a fresh skeleton for structural modifications. Herein, galaxamide and its 23 analogs (Gala01~Gala24) were designed and synthesized by substituting D-leucine with various proteinogenic amino acids or altering the amino acid configuration using the "3 + 2" strategy, and the in vitro antitumor activity of these cyclopeptides was studied utilizing the CCK-8 assay against two human tumor cell lines (A549 and K562) and one human normal cell line (293T). The total yields of galaxamide and its analogs reached 9.7% and 9.1-16.0%, respectively. CCK-8 assays demonstrated that these compounds showed broad-spectrum antitumor activity, with Gala04 exhibiting outstanding activity against K562 cells (IC50 = 4.2 µM). The anticancer efficacy of galaxamide analogs against tumor cell lines was significantly influenced by the quantity of D-leucines and the D-leucine position.

N-(2-chloro-5-(3-(pyridin-4-yl)-1H-pyrazolo [3,4-b]pyridin-5-yl)pyridin-3-yl)-4-fluorobenzenesulfonamide, namely, FD274, is a promising 7-azaindazole-based PI3K inhibitor candidate with high antitumor efficacy against acute myeloid leukemia and reduced cardiotoxicity in the zebrafish model. To advance its clinical translation, in this work, we conducted comprehensive assessments of the cardiotoxicity of FD274 and preliminarily investigated its synergistic antitumor effects with an FLT3 inhibitor, Gilteritinib. The cardiotoxicity profile of FD274, as well as its bioisostere FD268 (positive control), was evaluated using the C57BL/6 mouse model and the H9C2 cell line. The cardiotoxicity of FD274 after a consecutive 20-day treatment period was further assessed in an HL-60 xenograft mouse model. The synergistic cytotoxicity of FD274 with Gilteritinib was evaluated in the HL-60 cell line and the FLT3-ITD cell line MV-4-11. FD274 demonstrated lower adverse effects associated with cardiac dysfunction, oxidative stress, and myocardial injury in the C57BL/6 mouse model and in the H9C2 cell line as compared with FD268. Its negligible adverse effect was further validated in the HL-60 xenograft mice after the 20-day treatment process. Moreover, FD274 demonstrated a synergistic pro-apoptotic effect with Gilteritinib in both HL-60 and MV-4-11 cells. Our findings confirmed the low cardiotoxicity of FD274 and its great potential for combination therapy with Gilteritinib, warranting further development.

In this study, twenty-four new furoxan and seco-coumarin hybrids were synthesized, and their antiproliferative activities against four breast cancer cells (MCF-7/ADR, MCF-7, MDA-MB-231, and MDA-MB-468) were evaluated. Among them, compound 9e exhibited significant toxicity against MCF-7/ADR cells compared to MCF-7 cells, with a 1401-fold increase, indicating its high collateral sensitivity. Meanwhile, 9e exhibited relatively lower toxicity to normal cell lines and improved solubility compared to the previous active compound, 4A93, which features a coumarin integrity core. Preliminary pharmacological studies revealed that 9e might be a potential P-glycoprotein substrate, which enters the lysosomes of MCF-7/ADR to release effective concentrations of nitric oxide, producing reactive oxygen species and inducing apoptosis. Moreover, laser confocal microscopy and Western Blot experiments showed that 9e could induce autophagy in MCF-7/ADR cells. Additionally, the anti-tumor activity of compound 9e could be inhibited by the ferroptosis inhibitor Fer-1. These results suggest that the remarkable antiproliferative potency of these hybrids in MCF-7/ADR may be related to multiple anticancer mechanisms. As a novel nitric oxide donor, compound 9e was used to explore the potential development of an anti-tumor candidate with special pharmacological mechanisms to overcome multidrug resistance in breast cancer.

The use of plant extracts and the compounds isolated from them for the treatment of cancer is an area of active research, given their therapeutic potential. This work focused on evaluating the literature related to the antiproliferative activity of extracts obtained from plants of the genus Tabebuia and molecules isolated in vitro or in vivo. For the search, MeSH and DECS terms were employed in the PubMed, Scopus, and SciELO databases. Research has shown that plant extracts derived from plants of the genus Tabebuia exhibit potential applications in the search for new molecules with antiproliferative activity. Among the isolated molecules, the most evaluated correspond to β-lapachone (naphthoquinone); however, molecules with antiproliferative potential belonging to groups such as iridoids, flavonoids, quinones, furanonaphthoquinones, triterpenes, and polysaccharides have also been isolated and reported. Additionally, synthesized molecules have been evaluated on the basis of the modifications made to the structures of molecules isolated from the plant extracts to increase their activity, aiming to develop more potent antitumor agents for future clinical use.

Photodynamic therapy (PDT) is a minimally invasive technique-used for the local eradication of neoplastic cells-that exploits the interaction of light, oxygen, and a photo-responsive drug called photosensitizer (PS) for the local generation of lethal ROS. Push-pull chromophores, that bear electron donor (D) and acceptor (A) groups linked through a π-electron bridge, are characterized by a non-homogeneous charge distribution in their excited state, with charge transfer from one extremity of the chain to the other one (Internal Charge Transfer-ICT). This phenomenon has a direct impact on the photophysical features of the push-pull compounds, as the bathochromic shift of the emission maxima and intersystem crossing (ISC) of the excited state are directly connected with the production of reactive oxygen species (ROS). In continuing our research regarding the synthesis and use of oligophenylene ethynylenes (OPEs) in PDT, two new push-pull glycosyl OPE-NOF and OPE-ONF-featuring electron-donor N,N-dimethylamino (N) and dimetoxyaryl (O) and acceptor tetrafluoroaryl (F) moieties on the OPE chain-have been efficiently prepared. The interchanged position of the D groups onto the conjugated skeleton was aimed to tune and optimize the push-pull effect, while the introduction of glucoside terminations was directed to give biocompatibility and bioaffinity to the chromophores. OPE-NOF, OPE-ONF, and the synthetic intermediates were fully characterized, and their photophysical properties were investigated by using UV-Vis absorption and emission spectroscopy. OPE-NOF showed a strong charge-transfer character and high PDT effect on HeLa cancer cells when irradiated with non-harmful blue light, causing massive cancer cell death.

Quercetin (QUE) is a bioactive flavonoid that is naturally present in various fruits and possesses many pharmacological activities. Despite its health benefits, the bioavailability of quercetin is relatively low due to its crystalline form and hydrophobic structure. An approach to overcoming these drawbacks is its incorporation into amorphous polymer matrices. PLA and PLA/PEG fibrous materials loaded with QUE were obtained by electrospinning. The XRD analysis revealed a visible decrease in the crystallinity of QUE after its incorporation into PLA and PLA/PEG fibers. The obtained fibrous materials and, especially, the PLA/PEG mat loaded with the flavonoid exhibited high antioxidant activity due to the better wettability and higher release rate of the bioactive compound. Moreover, the PLA/QUE and PLA/PEG/QUE mats possessed antibacterial properties against Staphylococcus aureus and Pseudomonas aeruginosa. Furthermore, the antitumor activity of the prepared mats was tested against SH-4 cancer cells and HaCaT keratinocytes. The obtained results reveal that the QUE-loaded fibrous mats exhibited high anticancer activity against cancer cells but lower toxicity to normal keratinocytes. The combined antioxidant, antibacterial and in vitro antitumor activities render these novel PLA-based materials loaded with QUE promising candidates for wound dressing applications and for application in local tumor treatment.

Leukemia is a malignant tumor of the hematopoietic system. Approximately 15% of adult leukemias are chronic myeloid leukemias (CMLs), and this incidence increases annually. The BCR-ABL oncoprotein drives the initiation, promotion, and progression of CML. Although tyrosine kinase inhibitors (TKIs) are first-line therapies for CML, BCR-ABL-mediated drug resistance limits their clinical efficacy and patient prognosis. Perillaldehyde (PAE), a monoterpene and primary volatile oil from perilla, is a promising small-molecule candidate for degrading BCR-ABL and has potential medical applications. The molecular mechanism showed that PAE regulated the expression of autophagy- and apoptosis-related proteins in K562 cells. Confocal laser observation showed that PAE damaged the mitochondrial membrane potential and induced ROS generation. Further evaluations indicated that PAE targeted HSP70 and inactivated the phosphorylation of BCR-ABL, thereby inhibiting its downstream proteins. This study may produce a lead compound for CML therapy as PAE may be an effective treatment for further exploration.

This study focuses on the extraction, characterization, and biological evaluation of diterpenes from green coffee beans, specifically, cafestol and kahweol. These compounds, known for their potential health benefits, were isolated via optimized extraction and saponification processes. Separation was achieved using silver nitrate-impregnated silica gel, and structural elucidation was performed through advanced 1D and 2D NMR techniques, including HSQC, HMBC, and (IN)ADEQUATE. Due to kahweol's instability, the research prioritized cafestol for the synthesis of rhodamine B conjugates. Initial ester-linked conjugates proved unstable, prompting the development of more robust derivatives through amide linkage strategies and further functionalization via acetylation and oxidation reactions. Some oxidation methods led to furan ring cleavage, impacting structural integrity. Selected compounds were tested for cytotoxicity using SRB assays on human tumor cell lines (MCF7, A2780) and non-malignant fibroblasts (NIH 3T3). While the parent diterpenes and many derivatives showed minimal activity, several cafestol-rhodamine B conjugates demonstrated notable cytotoxic effects. Compound 6, in particular, exhibited selective activity against cancer cells with reduced toxicity toward non-malignant cells.