KB Cells Research Articles

Ecofriendly Curcumin-Conjugated Copper Oxide Nanoparticles: Targeted Cytotoxicity and Apoptosis in Oral Carcinoma KB Cells

Ecofriendly Curcumin-Conjugated Copper Oxide Nanoparticles: Targeted Cytotoxicity and Apoptosis in Oral Carcinoma KB Cells

Biofilm targeting with chitosan-based nanohydrogel containing Quercus infectoria G. Olivier extract against Streptococcus mutans: new formulations of a traditional natural product.

Biofilm formation has a crucial role in the cariogenic virulence of Streptococcus mutans, which leads to resistance to common antibacterials. The antimicrobial resistance crisis has led to increased research about traditional natural products. Quercus infectoria extract (QI extract) and nano hydrogels containing QI extract (QI-NH) and tannic acid (TA-NH) were evaluated against this pathogen. QI extract was analyzed by HPLC and the physiological characteristics of nanohydrogels were assessed by SEM, FTIR, zeta potential, DLS and determination of release kinetics and encapsulation efficiency. Determination of MIC and MBC of the material and their anti-biofilm effect was done by the microtiter method and on the extracted tooth surface. The properties of extracts and nano hydrogels in the expression of genes codifying glucosyltransferases (gtfB, gtfC and gtfD) and glucan binding protein B (gbpB) were quantified. Their toxicity was tested by the MTT method against the KB cell line. According to HPLC, 55.18% of QI extract contained TA. The encapsulation efficiency of QI-NH and TA-NH was equal to 60% and 80%, respectively. SEM and FTIR exhibited that QI extract and TA were successfully entrapped in the networks resulting from the chemical bonding of chitosan and TPP. The average size of QI-NH and TA-NH was 70.45 and 58.43nm, and their zeta potential was 6.17 ± 2.58 and 0.25 ± 0.03 mv, respectively. PDI < 0.3 of nano hydrogels indicated the favorable polydispersity of nanohydrogels. MIC of QI extract, QI-NH and TA-NH were 937.5, 30 and 10µg/ml, respectively. Also their MBIC50 was 35.1, 2.1 and 0.95µg/ml, respectively, and the extracts and nano hydrogels restrained the biofilm maturation on enamel. The pivotal genes of S. mutans in biofilm formation were significantly less expressed by treatment with QI-NH and TA-NH than others. Based on the MTT test, QI-NH had less acute toxicity than QI extract and TA-NH. IC50 of QI-NH was calculated as 775.4µg/ml, while it was equal to 3.12µg/ml for chlorhexidine as a common antibacterial agent. QI-NH, a new formulation derived from traditional anti-caries, can be a safe and efficient option to combat dental biofilm.

Antioxidant and anticancer activities of hesperetin and its novel formulations in KB cells.

This study aimed to formulate the hesperetin nanostructured lipid carriers (NLCs) containing oro-mucosal gel for its activity assessment on the KB cell line. NLCs were prepared with glyceryl monostearate, oleic acid, and lecithin using a modified constant-temperature emulsification technique. The particle size analysis, in vitro drug release studies, etc., of prepared NLCs were evaluated. The formulated gels were analyzed with respect to spreadability, extrudability, swelling index, texture analysis, etc. The particle size, polydispersity index, zeta potential, and drug entrapment of nanocarriers were recorded to be 221.733 ± 61.536nm, 0.381 ± 0.091, - 51.433 ± 4.143mV, and 89.29%, respectively. The optimized NLCs in 24h released 87.14 ± 6.62% of the drug. The round shape of NLCs was noticed with scanning electron microscopy. The pH, spreadability, extrudability, swelling index, content uniformity, and drug release studies of hesperetin NLCs-containing gel (HNG) were found to be 6.81 ± 0.04, 2.49 ± 0.04cm.mg/s, 539.04 ± 32.88g/cm2, 4.27 ± 0.47, 107.98 ± 1.93%, and 90.17 ± 6.67% (in 48h), respectively. The developed formulations showed promising in vitro anticancer and antioxidant activities. HNP results authorize that the formulation may be beneficial for the treatment of oral cancer.

Eco-friendly synthesis of betanin-conjugated zinc oxide nanoparticles: antimicrobial efficacy and apoptotic pathway activation in oral cancer cells.

Phytochemical-based synthesis of nanoparticles (NPs) is an eco-friendly approach with various biomedical applications. Betanin, a natural pigment in beetroot, has antioxidant, anti-inflammatory, and antimicrobial properties. When conjugated with zinc oxide nanoparticles (ZnO NPs), these properties are enhanced. This study aimed to synthesize betanin-ZnO nanoparticles (BE-ZnO-NPs) and evaluate their biological potential. BE-ZnO-NPs were synthesized and characterized using UV-Visible spectroscopy, FTIR, FE-SEM, HR-TEM, EDX, XRD, DLS, and zeta potential analysis. In silico studies assessed interactions with oral pathogen proteins, and antibacterial activity was tested against Enterococcus faecalis, Candida albicans, Staphylococcus aureus and Streptococcus mutans. Antioxidant potential and cytotoxicity on KB cells were evaluated through scavenging assays, MTT assay, and qRT-PCR. Betanin synthesized ZnO NPs UV-Vis results showed surface plasmon resonance at 388 nm, and FTIR confirmed betanin role as a capping agent. FE-SEM and TEM revealed particles of 37 nm. EDX confirmed zinc content, and XRD showed a hexagonal structure. Zeta potential was -3.3 mV, and DLS indicated a size of 38.73 nm. In silico analysis showed strong binding to E. faecalis (-8.0 Kcal/mol). BE-ZnO-NPs demonstrated antibacterial activity at 100 µg/mL, with inhibition zones of 18 ± 0.14 mm for E. faecalis and 14 ± 0.18 mm for S. mutans. In contrast, BE demonstrated antibacterial activity at 100 µg/mL, with zone of inhibition of 10.6 ± 0.14 mm for E. faecalisand 11.4 ± 0.18 mm for S. mutans.Antioxidant assays revealed dose-dependent scavenging activity. Cytotoxicity showed an IC50 of 24.29 µg/mL, with qRT-PCR indicating apoptosis through the BCL2/BAX/P53 pathway. BE-ZnO-NPs exhibited significant antibacterial and antioxidant activities and demonstrated the ability to induce apoptosis in oral cancer cells via the BCL-2/BAX/P53 signalling pathway. These findings highlight the potential of BE-ZnO-NPs as promising antimicrobial agents for tooth infections and as therapeutic agents for oral tumour treatment.

Madecassic acid analogues with a five-membered A-ring and their cytotoxic activity

The structural modification of madecassic acid focused on the contraction of the six-membered A-ring to a five-membered ring, combined with the dehydration of 6-OH to form a new double bond and formation of the esterification or amidation at C-28. The synthesised structures were identified based on the analysis of their NMR and EIS-MS data. Eighteen new madecassic acid analogues were tested in vitro for their cytotoxicity against three cancer cell lines, including human mouth carcinoma (KB), human hepatocellular carcinoma (HepG2), and human lung carcinoma (A549) using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. Among them, compounds 5 and 12 exhibited potent and selective cytotoxic activity in KB and HepG2 cell lines, with IC50 values ranging from 3.57 to 6.32 µM. The results also indicated that analogues with a 5-membered A-ring containing an α,β-unsaturated aldehyde esterified at C-23 showed a decrease in their cytotoxic activity compared to precursors in the tested cancer cells.

Synergistic Action of Rutin-Coated Zinc Oxide Nanoparticles: Targeting Biofilm Formation Receptors of Dental Pathogens and Modulating Apoptosis Genes for Enhanced Oral Anticancer Activity.

Oral diseases are often associated with bacterial and fungal pathogens such as Staphylococcus aureus, Streptococcus mutans, Enterococcus faecalis, and Candida albicans. This research explored a novel approach to addressing these pathogens by synthesizing zinc oxide nanoparticles (ZnO NPs) coated with rutin (RT), a plant-derived compound. The synthesized ZnO-RT NPs were comprehensively characterized using UV-Vis spectrophotometer, SEM, and EDAX techniques to confirm their structural composition. The antioxidant potential was assessed through free radical scavenging assays. Additionally, the antimicrobial activity of ZnO-RT NPs was evaluated using a zone of inhibition assay against oral pathogens. Molecular docking studies with the Autodock tool were performed to elucidate the interactions between RT and the receptors of oral pathogens. The findings demonstrated that ZnO-RT NPs exhibited robust free radical scavenging activity. Furthermore, they showed significant antimicrobial activity with a minimal inhibitory concentration of 40 μg/mL against oral pathogens. ZnO-RT NPs also displayed dose-dependent anticancer effects on human oral cancer cells at concentrations of 10, 20, 40, and 80 μg/mL. Mechanistic insights into the anticancer activity on KB cells revealed the upregulation of apoptotic genes. This study underscores the promising potential of ZnO-RT NPs for dental applications due to their strong antioxidant, anticancer, and antimicrobial properties. These nanoparticles offer a hopeful prospect for addressing oral pathogen challenges and enhancing overall oral health.

Virtual screening and lead optimization of Desmostachya bipinnata-derived FGFR inhibitors for oral squamous cell carcinoma management

BackgroundOral cancer remains a major global health challenge with limited therapeutic options, highlighting the need for novel treatments. Phytochemicals derived from Desmostachya bipinnata (Db), a plant used in traditional Chinese medicine for its anti-inflammatory and analgesic properties, have demonstrated potential anti-cancer effects. However, their mechanisms of action, particularly in targeting Fibroblast Growth Factor Receptor (FGFR) in oral cancer, are not well characterized. ObjectiveThis study aimed to leverage in-silico drug design methodologies to identify bioactive compounds from Db with potential FGFR-inhibiting activity for the treatment of oral cancer. MethodologyAn MTT assay was conducted using KB cell lines to evaluate cytotoxic effects, while thirty-eight phytochemicals from Db were screened through in silico approaches for their pharmacokinetics, toxicity, and drug-likeness. Molecular docking studies were performed to assess binding affinities to the FGFR protein. The biological activity and toxicity of the compounds were predicted to prioritize candidates for further investigation. ResultsFourteen compounds were identified as promising candidates based on their drug-like properties, favourable pharmacokinetic profiles, significant FGFR binding affinities, and predicted anti-cancer activity. These compounds also demonstrated potential for oral bioavailability and central nervous system penetration, supporting their candidacy for further drug development. Notably, the traditional use of Desmostachya bipinnata in TCM emphasizes its role in enhancing overall vitality and immune function, which may synergize with the identified FGFR-inhibiting properties in the context of oral cancer treatment ConclusionThe phytochemicals from Desmostachya bipinnata exhibit significant potential as FGFR-targeted therapeutic agents for oral cancer. Further experimental validation and optimization of these lead compounds could contribute to the development of novel, effective treatments for oral cancer and related conditions

New Cytotoxic Sesquiterpene Lactones from the Leaves of Tithonia Diversifolia and their Apoptosis Effect Evaluation in KB Cancer Cells.

From the leaves of Tithonia diversifolia, nine sesquiterpenoids (1-9), including two new ones (tagitinin J (1) and tagitinin K (2)) were isolated and structurally determined. Their chemical structures were elucidated by extensive analyses of the HRESIMS and NMR spectral data, as well as comparison with the literature. All of the isolated compounds (except compounds 7-9) significantly exhibited cytotoxic activity against four human cancer cell lines (KB, HepG2, A549 and MCF7), with IC50 values ranging from 0.29-17.0 μM, which were in the same range as the positive control ellipticine or even lower. Further, the apoptosis induction effects of two new compounds 1 and 2 were also investigated and reported. While compound 2 did not induce the apoptosis in KB cells at test concentrations, compound 1 was found to possess anti-proliferative activity through concentration-dependently inducing cell cycle arrest at S phase, morphological changes, activation of caspase 3, and an increase in the early-stage apoptosis of KB cells at a concentration of 7.26 μM.

Chemical Composition, Anti-microbial, and Cytotoxic Activities of Essential Oil from Magnolia bidoupensis Q. N. Vu leaves, an Endemic Species to the Central Highlands of Vietnam.

An analysis was conducted on the essential oil extracted from the leaves of Magnolia bidoupensis utilizing GC-MS, revealing thirty-three constituents that account for 98.9% of the essential oil. The main components included pogostol (22.4%), δ-selinene (16.2%), and α-amorphene (14.7%). Bioassays were then performed to evaluate the oil's biological activity. The essential oil exhibited antimicrobial activity against all tested microorganisms (six bacterial strains and one fungal strain) using the minimum inhibitory concentration (MIC) method. Additional cytotoxicity tests were conducted on KB, HepG2, MCF-7, and A549 cancer cell lines using the MTT method. The essential oil exhibited strong cytotoxic effects on all four cell lines, with IC50 values ranging from 1.37 ± 0.05 μg/mL (KB) to 2.40 ± 0.06 μg/mL (A549).

Polyprenylated Benzoylphloroglucinols Isolated from Garcinia Species and Their Cytotoxic Effects on Cancer Cell Lines.

Polyprenylated benzoylphloroglucinols (PPBPs) make up a group of complex natural products with anticancer potentials that are mainly distributed in Garcinia plants. As part of our intensive exploration on new bioactive substances from this genus, we report two undescribed PPBPs, picrorhizones I (1) and J (2), along with four known analogues (3-6) from the stem bark of Garcinia picrorhiza and Garcinia gracilis. The new structures were elucidated on the basis of spectroscopic analysis, particularly 1D and 2D NMR and HRESIMS, whereas the absolute configurations were determined by a combination of ECD and NMR calculations coupled with a DP4+ probability analysis. Being the least class in genus Garcinia, picrorhizone I possesses a type-A structure with the position of a benzoyl moiety attaching to one of the bridgehead carbons of a bicyclo[3.3.1]nonane skeleton, which differs from its major type-B counterparts. This work also represents the first report on the occurrence of PPBPs in G. gracilis. The cytotoxic evaluation of the isolated compounds revealed that isogarcinol (4) and garciyunnanin L (5) significantly inhibited the growth of KB and Hela S3 cancer cells with IC50 values lower than 10 μM, while 5 was also strongly active against the Hep G2 cancer cell line with an IC50 value of 8.02 μM. Among the B-class derivatives bearing a lavandulyl side chain, cyclization of the moiety in the bicyclic phloroglucinol skeleton enhanced the cytotoxic properties on cancer cells.

Potential of Silymarin and Metformin Co-Loaded Nanostructured Lipid Carriers Containing Mucoadhesive Thermogel on KB Cells of Oral Cancer

Potential of Silymarin and Metformin Co-Loaded Nanostructured Lipid Carriers Containing Mucoadhesive Thermogel on KB Cells of Oral Cancer

Cytotoxic prenylated xanthone derivatives from the twigs of Garcinia cowa

A new prenylated xanthone, kaennacowanol D (1), was isolated from the twigs of Garcinia cowa together with 22 known analogs. The structure of the new metabolite was elucidated by extensive spectroscopic analysis, particularly using HRMS and NMR. Kaennacowanol D is the first example of a natural xanthone containing a levulinyl group incorporated at the terminal prenyl unit via ester bond. Cytotoxic evaluation of the isolated compounds on human cancer cells showed that jacareubin (13), 2-prenylisojacareubin (17), nigrolineaxanthone E (23) were significantly active against KB and Hela S3 cell lines with IC50 values ranging from 1.78 to 9.52 µM, while 17 and 23 also suppressed the growth of MCF-7, Hep G2, and HT-29 cells with IC50 values lower than 10 µM.

Investigating the Anticancer Potential of Biochanin A in KB Oral Cancer Cells Through the NFκB Pathway.

Squamous cell carcinoma (SCC) is a malignancy primarily affecting squamous cells. Its development is linked to multiple risk factors, such as alcohol and tobacco consumption, human papillomavirus (HPV) infection, and Epstein-Barr Virus (EBV) infection. Biochanin A (BCA), a phytoestrogen extracted from red clover, has been extensively researched for its therapeutic properties. It spans antioxidant activity, anti-inflammatory effects, neuroprotection, cardioprotection, and anticancer potential in different bodily systems. However, its impact on oral cancer remains unexplored. Therefore, this investigation aims to assess the potential anticancer effects of BCA, specifically on KB oral cancer cells. This study utilized KB cells to evaluate the impact of BCA on various cellular parameters, including cell viability, apoptosis, intracellular ROS production, mitochondrial membrane potential, and cell migration. BCA treatment induced several notable effects on KB cells, including reduced cell viability, altered morphology suggestive of apoptosis, heightened oxidative stress, and alterations in mitochondrial membrane potential. Moreover, BCA treatment demonstrated an inhibitory effect on cell migration. The study further investigated the impact of BCA on antioxidant enzyme activities and lipid peroxidation, revealing decreased antioxidant enzyme activities and increased lipid peroxidation across different BCA concentrations (IC50 and IC90). Immunocytochemistry and qRT-PCR analyses unveiled that BCA treatment at varying doses (IC50 and IC90) downregulated the expression of nuclear factor-κB (NF-κB) subunits p50 and p65, pivotal players in cancer progression. In summary, this study sheds light on the promising potential of BCA as an anticancer therapeutic agent for treating oral cancer. Its demonstrated ability to induce apoptosis, perturb cellular functions, and modulate gene expression within cancer cells underscores its significance. Nonetheless, further research, particularly following animal studies, is imperative to comprehensively grasp the breadth of BCA's effects and its viability for clinical applications.

Chemical Composition, Anti-Microbial, and Cytotoxic Activities of Essential Oils from Blumea densiflora var. hookeri (C.B. Clarke ex Hook.f.) C.C. Chang & Y.Q. Tseng Leaves from Vietnam.

The essential oil from the leaves of Blumea densiflora var. hookeri was analyzed using GC-MS, and bioassays were performed. GC-MS identified thirty-four constituents, representing 79.1 % of the oil composition. The major compounds identified in the oil were (E)-caryophyllene (15.3 %), viridiflorol (5.5 %), trans-dauca-4(11),7-diene (4.6 %), spathulenol (4.4 %), and isolongifolan-7-α-ol (4.3 %). The antimicrobial activity of the oil was assessed to determine its efficacy against six bacterial strains and one fungal strain using minimum inhibitory concentration (MIC) methods. The essential oil demonstrated antimicrobial activity against all tested microorganisms. A cytotoxicity assay was performed on KB and A549 cancer cell lines using the MTT method. The essential oil displayed strong cytotoxic effects on both cell lines, with IC50 values of 1.40±0.05 μg/mL for KB and 1.72±0.04 μg/mL for A549.

Synergistic Action of Vanillic Acid-Coated Titanium Oxide Nanoparticles: Targeting Biofilm Formation Receptors of Dental Pathogens and Modulating Apoptosis Genes for Enhanced Oral Anticancer Activity.

The prevalence of bacterial and fungal infections is caused byS. aureus, S. mutans, E. faecalis, and Candida albicans are often associated with dental illnesses. In the present study, a unique strategy was used to combat these diseases by fabricatingtitanium dioxide nanoparticles (TiO2 NPs) conjugated with the plant-based molecule vanillic acid (VA).Molecular modeling investigations were performed to better understand the interactions among vanillic acid and dental pathogen receptors using the Autodock program. The findings indicated that VA-TiO2 NPs exhibited strong free radical scavenging activity. Additionally, they showed excellent antibacterial action towards dental pathogens, with a minimum inhibition level of 60 μg/mL. Furthermore, at doses of 15 μg/mL, 30 μg/mL, 60 μg/mL, and 120 μg/mL, VA-TiO2 NPs demonstrated concentration-dependent apoptotic impacts on human oral carcinoma cells. Apoptotic gene over-expression was identified by the molecular perspectives that revealed the anticancer mechanism of VA-TiO2 NPs on KB cells. This study highlights the promising suitability of VA-TiO2 NPs for dental applications due to their robust antioxidant, anticancer, and antimicrobial characteristics. These nanoparticles present an evident prospect for addressing oral pathogen challenges and improving overall oral health.

In Vitro Evaluation of Natural Extracts as Potential Anticancer Agents: A Study on KB Cell Lines

In Vitro Evaluation of Natural Extracts as Potential Anticancer Agents: A Study on KB Cell Lines

11-Azaartemisinin derivatives bearing halogenated aromatic moieties: Potent anticancer agents with high tumor selectivity

While artemisinin and its derivatives, including 11-azaartemisinin-based compounds, have shown promising anticancer activity, the integration of halogens into aromatic structures can amplify drug potency, metabolic stability, and selectivity. Herein, we present the synthesis of new novel 11-azaartemisinin derivatives bearing halogenated aromatic moieties connected via 1,2,3‐triazole bridges and evaluate their anticancer activities against three human tumor cell lines: epidermoid carcinoma (KB), hepatocellular carcinoma (HepG2), and human lung adenocarcinoma (A549). Among the synthesized compounds, six of them (8c-h) displayed good to excellent antiproliferative activity in the low micromolar range across all three human cancer cell lines. In general, the m-bromide (8c) and m-iodide (8d) compounds exhibited superior anticancer activities compared to their o- and p-analogs, as well as the m-chloride and m-fluoride compounds. The most promising m-Br compound (8c) displayed 50 % inhibition of KB, HepG2, and A549 cell growth at concentrations of 7.7, 42.5, and 15.5 μM, respectively. Notably, the m-Br compound (8c) exhibited approximately 32-, 6-, and 16-fold lower activity in normal cells (Hek293) compared to KB, HepG2, and A549 tumor cells, respectively, indicating a significant tumor-selectivity.

Boehmeria Nivea Extract (BNE-RRC) Reverses Epithelial-Mesenchymal Transition and Inhibits Anchorage-Independent Growth in Tumor Cells.

The epithelial-mesenchymal transition (EMT) phenotype, identified as a significant clinical indicator in regard to cancer, manifests as a biological process wherein cells transition from having epithelial to mesenchymal characteristics. Physiologically, EMT plays a crucial role in tissue remodeling, promoting healing, repair, and responses to various types of tissue damage. This study investigated the impact of BNE-RRC on oral cancer cells (KB) and revealed its significant effects on cancer cell growth, migration, invasion, and the EMT. BNE-RRC induces the epithelial-like morphology in KB cells, effectively reversing the EMT to a mesenchymal-epithelial transition (MET). Extraordinarily, sustained culturing of cancer cells with BNE-RRC for 14 days maintains an epithelial status even after treatment withdrawal, suggesting that BNE-RRC is a potential therapeutic agent for cancer. These findings highlight the promise of BNE-RRC as a comprehensive therapeutic agent for cancer treatment that acts by inhibiting cancer cell growth, migration, and invasion while also orchestrating a reversal of the EMT process. In this study, we propose that BNE-RRC could be an effective agent for cancer treatment.

Dual inhibition of topoisomerase II and microtubule of podophyllotoxin derivative 5p overcomes cancer multidrug resistance

Compound 5p is a 4β-N-substituted podophyllotoxin derivative, which exhibited potent activity toward drug-resistant K562/A02 cells and decreased MDR-1 mRNA expression. Here, we further investigated its detail mechanism and tested its antitumor activity. 5p exerted catalytic inhibition of topoisomerase IIα, and didn’t show the inhibitor of topoisomerase I. 5p exhibited the inhibitory effect on microtubule polymerization. 5p showed potent anti-proliferation against breast cancer, oral squamous carcinoma, and their drug-resistant cell lines, with resistance index of 0.61 and 0.86, respectively. 5p downregulated the expression levels of P-gp in KBV200 cells and BCRP in MCF7/ADR cells in dose-dependent manner. Moreover, 5p induced KB and KBV200 cells arrest at G2/M phase by up-regulating the expression of γ-H2AX, p-Histone H3 and cyclin B1. 5p induced apoptosis and pyroptosis by increased the expression levels of cleaved-PARP, cleaved-caspase3, N-GSDME as well as LDH release in KB and KBV200 cells. In addition, 5p efficiently impaired tumor growth in KB and KBV200 xenograft mice. Conclusively, this work elucidated the dual inhibitor of topoisomerase II and microtubule of 5p and its mechanism of overcoming the multidrug resistance, indicating that 5p exerts the antitumor potentiality.

Synthesis and Preclinical Evaluation of [18F]AlF-NOTA-Asp2-PEG2-Folate as a Novel Folate-Receptor-Targeted Tracer for PET Imaging.

Recently, the folate receptor (FR) has become an exciting target for the diagnosis of FR-positive malignancies. Nevertheless, suboptimal invivo pharmacokinetic properties, particularly high uptake in the renal and hepatobiliary systems, are important limiting factors for the clinical translation of most FR-based radiotracers. In this study, we developed a novel 18F-labeled FR-targeted positron emission tomography (PET) tracer [18F]AlF-NOTA-Asp2-PEG2-Folate modified with a hydrophilic linker (-Asp2-PEG2) to optimize its pharmacokinetic properties and conducted a comprehensive preclinical assessment. The [18F]AlF-NOTA-Asp2-PEG2-Folate was manually synthesized within 30 min with a non-decay-corrected radiochemical yield of 16.3 ± 2.0% (n = 5). Among KB cells, [18F]AlF-NOTA-Asp2-PEG2-Folate exhibited high specificity and affinity for FR. PET/CT imaging and biodistribution experiments in KB tumor-bearing mice showed decent tumor uptake (1.7 ± 0.3% ID/g) and significantly decreased uptake in kidneys and liver (22.2 ± 2.1 and 0.3 ± 0.1% ID/g at 60 min p.i., respectively) of [18F]AlF-NOTA-Asp2-PEG2-Folate, compared to the known tracer [18F]AlF-NOTA-Folate (78.6 ± 5.1 and 5.3 ± 0.5 % ID/g at 90 min p.i., respectively). The favorable properties of [18F]AlF-NOTA-Asp2-PEG2-Folate, including its efficient synthesis, decent tumor uptake, relatively low renal uptake, and rapid clearance from most normal organs, portray it as a promising PET tracer for FR-positive tumors.