Anticancer efficacy triggered by synergistically modulating the homeostasis of anions and iron: Design, synthesis and biological evaluation of dual-functional squaramide-hydroxamic acid conjugates.

Targeting the homeostasis of anions and iron has emerged as a promising therapeutic approach for the treatment of cancers. However, single-targeted agents often fall short of achieving optimal treatment efficacy. Herein we designed and synthesized a series of novel dual-functional squaramide-hydroxamic acid conjugates that are capable of synergistically modulating the homeostasis of anions and iron. Among them, compound 16 exhibited the most potent antiproliferative activity against a panel of selected cancer cell lines, and strong in vivo anti-tumor efficacy. This compound effectively elevated lysosomal pH through anion transport, and reduced the levels of intracellular iron. Compound 16 could disturb autophagy in A549 cells and trigger robust apoptosis. This compound caused cell cycle arrest at the G1/S phase, altered the mitochondrial function and elevated ROS levels. The present findings clearly demonstrated that synergistic modulation of anion and iron homeostasis has high potentials in the development of promising chemotherapeutic agents with dual action against cancers.

Safety, tolerability, pharmacokinetics, and antitumor activity of adavosertib in Japanese patients with advanced solid tumors: A phase I, open-label study.

INTRODUCTION: We aimed to assess the safety, pharmacokinetic profile, and antitumor activity of adavosertib monotherapy in Japanese patients with advanced solid tumors. MATERIALS AND METHODS: This was a single-center, open-label, phase I study with two consecutive cohorts (250 mg and 200 mg cohorts). Patients received adavosertib at 250 mg or 200 mg, orally once daily for 5 days on and 2 days off for Weeks 1 and 2 of a 21-day cycle. RESULTS: Dose-limiting toxicities (Grade 3 febrile neutropenia) occurred in 2/6 patients in the 250 mg cohort. None of the three patients in the 200 mg cohort developed dose-limiting toxicities. The most frequent treatment-emergent adverse event was nausea (250 mg: 83.3 %; 200 mg: 100.0 %). Median time to peak drug concentration was 4.03 and 2.08 h after the first dose and 2.82 and 1.90 h after multiple dosing in the 250 and 200 mg cohorts, respectively; respective mean terminal elimination half-lives were 7.36 and 7.30 h (first dose) and 10.55 and 8.88 h (multiple dosing). Systemic exposure increased in a slightly more than dose-proportional manner. No RECIST v1.1 response was observed. Disease control rate was 0 % and 33.3 % in the 250 and 200 mg cohorts, respectively. One patient (33.3 %) in the 200 mg cohort showed a best overall response of stable disease at ≥ 8 weeks; the rest showed progressive disease. CONCLUSIONS: Adavosertib 200 mg once daily was well tolerated in this patient population and no safety concerns were raised. Exposure increased in a slightly more than dose-proportional manner and limited antitumor activity was shown. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04462952.

Improving In Vivo Tumor Accumulation and Efficacy of Platinum Antitumor Agents by Electronic Tuning of the Kinetic Lability.

The impact of kinetic lability or reactivity on in vitro cytotoxicity, stability in plasma, in vivo tumor and tissue accumulation, and antitumor efficacy of functional platinum(II) (Pt) anticancer agents containing a O˄O ß-diketonate leaving ligand remain largely unexplored. To investigate this, we synthesized Pt complexes [(NH3 )2 Pt(L1-H)]NO3 and [(DACH)Pt(L1-H)]NO3 (L1=4,4,4-trifluoro-1-ferrocenylbutane-1,3-dione, DACH=1R,2R-cyclohexane-1,2-diamine) containing an electron deficient [L1-H]- O˄O leaving ligand and [(NH3 )2 Pt(L2-H)]NO3 and [(DACH)Pt(L2-H)]NO3 (L2=1-ferrocenylbutane-1,3-dione) containing an electron-rich [L2-H]- O˄O leaving ligand. While all four complexes have comparable lipophilicity, the presence of the electron-withdrawing CF3 group was found to dramatically enhance the reactivity of these complexes toward nucleophilic biomolecules. In vitro cellular assays revealed that the more reactive complexes have higher cellular uptake and higher anticancer potency as compared to their less reactive analogs. But the scenario is opposite in vivo, where the less reactive complex showed improved tissue and tumor accumulation and better anticancer efficacy in mice bearing ovarian xenograft when compared to its more reactive analog. Finally, in addition to demonstrating the profound but contrasting impact of kinetic lability on in vitro and in vivo antitumor potencies, we also described the impact of kinetic lability on the mechanism of action of this class of promising antitumor agents.

Design and synthesis of sulfonamides incorporating a biotin moiety: Carbonic anhydrase inhibitory effects, antiproliferative activity and molecular modeling studies.

Sulfonamides constitute an important class of classical carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. Herein we have accomplished the conjugation of biotin with an ample number of sulfonamide motifs with the aim of testing them in vitro as inhibitors of the human carbonic anhydrase (hCA) isoforms I and II (cytosolic isozymes), as well as hCA IX and XII (transmembrane, tumor-associated enzymes). Most of these newly synthesized compounds exhibited interesting inhibition profiles, with activities in the nanomolar range. The presence of a 4-F-C6H4 moiety, also found in SLC-0111, afforded an excellent selectivity towards the tumor-associated hypoxia-induced hCA isoform XII with an inhibition constant (KI) of 4.5 nM. The 2-naphthyl derivative was the most potent inhibitor against hCA IX (KI = 6.2 nM), 4-fold stronger than AAZ (KI = 25 nM) with very good selectivity. Some compounds were chosen for antiproliferative activity testing against a panel of 3 human tumor cell lines, one compound showing anti-proliferative activity on glioblastoma, triple-negative breast cancer, and pancreatic carcinoma cell lines.

Optimization of L-glutaminase production by Monascus ruber URM 8542 isolated from ice cream industrial effluent.

L-glutaminase is a hydrolytic enzyme with wide biotechnological applications. Mostly, these enzymes are employed in the feed industry for flavor enhancement and acrylamide mitigation. Also, L-glutaminase may have antiviral and antineoplastic effects making it a good choice for pharmaceutical applications. In this study, the strain Monascus ruber URM 8542 was identified through classical and molecular taxonomy using partial sequencing of ß-tubulin and calmodulin genes. Subsequently, the optimal culture conditions were evaluated by submerged fermentation (L-glutamine 10 g.L- 1) for L-glutaminase excretion. The isolate was identified as M. ruber URM 8542 which showed significant extracellular enzyme production with a yield of 11.4 times in relation to the specific activity of intracellular L-glutaminase. Regarding the optimization experiments, several factors such as L-glutamine concentration, temperature, and pH were compared using a full factorial design (23). The concentrations greater than 1% proved to be significantly better for glutaminase production (R2 = 0.9077). Additionally, the L-glutaminase was optimally active at pH 7.0 and 30 ºC. The L-glutaminase was remarkably stable across an alkaline pH range (7.0-8.0) and had a thermal stability ranging from 30 ºC to 60 ºC for 1 h. Taken together, these findings suggest that the L-glutaminase produced by M. ruber is a promising candidate for pharmacological application, although further studies need to be performed. To the best of our knowledge, this is the first report of L-glutaminase production by Monascus ruber.

Cyclic anthraquinone derivatives, unique G-quadruplex binders, selectively induce cancer cell apoptosis and inhibit tumor growth.

Cyclic anthraquinone derivatives (cAQs), which link two side chains of 1,5-disubstituted anthraquinone as a threading DNA intercalator, have been developed as G-quartet (G4) DNA-specific ligands. Among the cAQs, cAQ-mBen linked through the 1,3-position of benzene had the strongest affinity for G4 recognition and stabilization in vitro and was confirmed to bind to the G4 structure in vivo, selectively inhibiting cancer cell proliferation in correlation with telomerase expression levels and triggering cell apoptosis. RNA-sequencing analysis further indicated that differentially expressed genes regulated by cAQ-mBen were profiled with more potential quadruplex-forming sequences. In the treatment of the tumor-bearing mouse model, cAQ-mBen could effectively reduce tumor tissue and had less adverse effects on healthy tissue. These results suggest that cAQ-mBen can be a potential cancer therapeutic agent as a G4 binder.

Electrochemical detection of genetic damage caused by the interaction of novel bifunctional anthraquinone-temozolomide antitumor hybrids with DNA modified electrode.

In this work, novel potential anthraquinone-temozolomide (TMZ) antitumor hybrids N-(2-((9,10-dioxo-9,10-dihydroanthracen-1-yl)amino)ethyl)-3-methyl-4-oxo-3,4-dihydroimidazo [5, 1-d][1,2,3,5]tetrazine-8-carboxamide (C-1) and 2-(9,10-dioxo-9,10-dihydroanthracen-1-yl)amino) ethyl-3-methyl-4-oxo-3,4-dihydroimidazo[5,1-d][1,2,3,5]tetrazine-8-carboxylate (C-9) were designed and synthesized successfully. The electrochemical behaviors of C-1 (C-9) involved the reversible processes of 9,10-anthraquinone ring, the irreversible reduction and oxidation processes of TMZ ring. Electrochemical biosensors were constructed with ctDNA, poly (dG) and poly (dA) modifying the surface of glassy carbon electrode (GCE) to evaluate the DNA oxidative damage caused by the interaction of C-1 (C-9) with DNA. Anthracycline skeleton and TMZ ring in C-1 (C-9) could exhibit bifunctional effects with both intercalating and alkylation modes toward DNA strands. The DNA biosensor had good practicability in mouse serum. The results of gel electrophoresis further demonstrated that C-1 (C-9) could effectively intercalated into ctDNA and disrupt plasmid conformation. Finally, anthraquinone-TMZ hybrid C-1 possessed high cytotoxicity toward A549 and GL261 cells, which could be a novel and optimal candidate for the clinic antitumor treatment.

Rethinking Biosynthesis of Aclacinomycin A.

Aclacinomycin A (ACM-A) is an anthracycline antitumor agent widely used in clinical practice. The current industrial production of ACM-A relies primarily on chemical synthesis and microbial fermentation. However, chemical synthesis involves multiple reactions which give rise to high production costs and environmental pollution. Microbial fermentation is a sustainable strategy, yet the current fermentation yield is too low to satisfy market demand. Hence, strain improvement is highly desirable, and tremendous endeavors have been made to decipher biosynthesis pathways and modify key enzymes. In this review, we comprehensively describe the reported biosynthesis pathways, key enzymes, and, especially, catalytic mechanisms. In addition, we come up with strategies to uncover unknown enzymes and improve the activities of rate-limiting enzymes. Overall, this review aims to provide valuable insights for complete biosynthesis of ACM-A.

Electrochemical detection of the oxidative damage of a potential pyrimido[5,4-g]pteridine-derived antitumor agent toward DNA.

In this work, we design and synthesize 2,2'-(7,9-dimethyl-2,4,6,8-tetraoxo-6,7,8,9-tetrahydropyrimido[5,4-g]pteridine-1,3(2H,4H)-diyl)bis(N,N-bis(2-chloroethyl)acetamide) (PT-MCA) as a novel DNA intercalator and potential antitumor agent. Electrochemical analysis reveals the redox process of PT-MCA on the electrode surface. The bioelectrochemical sensors are obtained by modifying the surface of GCE with calf thymus DNA (ctDNA), poly (dG), poly (dA), and G-quadruplex, respectively. The DNA oxidative damage induced by PT-MCA is investigated by comparing the peak intensity change of dGuo and dAdo and monitoring the peaks of the oxidation products of guanine and/or adenine (8-oxoGua and/or 2,8-oxoAde). UV-vis absorption and fluorescence spectra and gel electrophoresis are further employed to understand the intercalation of PT-MCA into DNA base pairs. Moreover, PT-MCA is proved to exhibit stronger anti-proliferation activity than mitoxantrone against both 4T1 and B16-F10 cancer cells. At last, the oxidative damage of PT-MCA toward ctDNA is not interfered by the coexistence of ions and also can be detected in real serums.

Heterostructures with Built-in Electric Fields for Long-lasting Chemodynamic Therapy.

Sustained signal activation by hydroxyl radicals (⋅OH) has great significance, especially for tumor treatment, but remains challenging. Here, a built-in electric field (BIEF)-driven strategy was proposed for sustainable generation of ⋅OH, thereby achieving long-lasting chemodynamic therapy (LCDT). As a proof of concept, a novel Janus-like Fe@Fe3 O4 -Cu2 O heterogeneous catalyst was designed and synthesized, in which the BIEF induced the transfer of electrons in the Fe core to the surface, reducing ≡Cu2+ to ≡Cu+ , thus achieving continuous Fenton-like reactions and ⋅OH release for over 18 h, which is approximately 12 times longer than that of Fe3 O4 -Cu2 O and 72 times longer than that of Cu2 O nanoparticles. In vitro and in vivo antitumor results indicated that sustained ⋅OH levels led to persistent extracellular regulated protein kinases (ERK) signal activation and irreparable oxidative damage to tumor cells, which promoted irreversible tumor apoptosis. Importantly, this strategy provides ideas for developing long-acting nanoplatforms for various applications.

Discovery of Novel 3,11-Bispeptide Ester Arenobufagin Derivatives with Potential in Vivo Antitumor Activity and Reduced Cardiotoxicity.

Arenobufagin, one of the bufadienolides isolated from traditional Chinese medicine Chan'su, exhibits potent antitumor activity. However, serious toxicity and small therapeutic window limits its drug development. In the present study, to our knowledge, novel 3,11-bispeptide ester arenobufagin derivatives have been firstly designed and synthesized on the base of our previous discovery of active 3-monopeptide ester derivative. The in vitro antiproliferative activity evaluation revealed that the moiety at C3 and C11 hydroxy had an important influence on cytotoxic activity and selectivity. Compound ZM350 notably inhibited tumor growth by 58.8 % at a dose 10 mg/kg in an A549 nude mice xenograft model. Therefore, compound ZM350 also presented a concentration-dependent apoptosis induction and low inhibitory effect against both hERG potassium channel and Cav1.2 calcium channel. Our study suggests that novel 3,11-bispeptide ester derivatives will be a potential benefit to further antitumor agent development of arenobufagin.

Two distinct rotations of bithiazole DNA intercalation revealed by direct comparison of crystal structures of Co(III)•bleomycin A2 and B2 bound to duplex 5'-TAGTT sites.

Bleomycins constitute a family of anticancer natural products that bind DNA through intercalation of a C-terminal tail/bithiazole moiety and hydrogen-bonding interactions between the remainder of the drug and the minor groove. The clinical utility of the bleomycins is believed to result from single- and double-strand DNA cleavage mediated by the HOO-Fe(III) form of the drug. The bleomycins also serve as a model system to understand the nature of complex drug-DNA interactions that may guide future DNA-targeted drug discovery. In this study, the impact of the C-terminal tail on bleomycin-DNA interactions was investigated. Toward this goal, we determined two crystal structures of HOO-Co(III)•BLMA2 "green" (a stable structural analogue of the active HOO-Fe(III) drug) bound to duplex DNA containing 5'-TAGTT, one in which the entire drug is bound (fully bound) and a second with only the C-terminal tail/bithiazole bound (partially bound). The structures reported here were captured by soaking HOO-Co(III)•BLMA2 into preformed host-guest crystals including a preferred DNA-binding site. While the overall structure of DNA-bound BLMA2 was found to be similar to those reported earlier at the same DNA site for BLMB2, the intercalated bithiazole of BLMB2 is "flipped" 180˚ relative to DNA-bound BLMA2. This finding highlights an unidentified role for the C-terminal tail in directing the intercalation of the bithiazole. In addition, these analyses identified specific bond rotations within the C-terminal domain of the drug that may be relevant for its reorganization and ability to carry out a double-strand DNA cleavage event.

Pyrazole derivatives as potent EGFR inhibitors: synthesis, biological evaluation and in silico and biodistribution study.

Aim: Synthesis of pyrazole derivatives as EGFR inhibitors. Materials & methods: Cytotoxicity and EGFR inhibitory effect were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and EGFR kits, respectively. The biodistribution of radioiodinated compound nanoparticles in tumor-bearing mice was studied. Results: The IC50 values of compound 4a against HepG2 cells and EGFR were 0.15 ± 0.03 and 0.31 ± 0.008 µM, respectively, while those of erlotinib were 0.73 ± 0.04 and 0.11 ± 0.008 µM, respectively. The binding scores of compound 4a and erlotinib to EGFR were -9.52 and -10.23 Kcal/mol, respectively. The maximum tumor uptake of radioiodinated compound after intravenous nanoparticle injection was 6.7 ± 0.3% radioactivity/g. Conclusion: Compound 4a is a promising antitumor agent with a potential EGFR inhibitory effect.

Synthesis of Acetogenin Analogs Comprising Pyrimidine Moieties Linked by Amine Bonds and Their Inhibitory Activity against Human Cancer Cell Lines.

Here, we synthesized three acetogenin analogs containing pyrimidine moieties linked by amine bonds, which represent the skeleton structure of pyrimidifen, a mitochondrial complex I-inhibiting insecticide. Replacing the pyrimidine moiety linked by the amine bond remarkably enhanced growth-inhibitory activity of the analogs against several human cancer cell lines. Moreover, these analogs selectively and potently inhibited the growth of these human cancer cell lines regardless of the pyrimidine substituents. Furthermore, COMPARE analyses suggested that these analogs inhibited cancer growth by inhibiting mitochondrial complex I. Our study provides insights into the design of acetogenin analogs as novel antitumor agents.

Discovery and SAR Study of Quinoxaline-Arylfuran Derivatives as a New Class of Antitumor Agents.

A novel class of quinoxaline-arylfuran derivatives were designed, synthesized, and preliminarily evaluated for their antiproliferative activities in vitro against several cancer cell lines and normal cells. The representative derivative QW12 exerts a potent antiproliferative effect against HeLa cells (IC50 value of 10.58 µM), through inducing apoptosis and triggering ROS generation and the accumulation of HeLa cells in vitro. Western blot analysis showed that QW12 inhibits STAT3 phosphorylation (Y705) in a dose-dependent manner. The BLI experiment directly demonstrated that QW12 binds to the STAT3 recombination protein with a KD value of 67.3 µM. Furthermore, molecular docking investigation showed that QW12 specifically occupies the pY+1 and pY-X subpocket of the SH2 domain, thus blocking the whole transmission signaling process. In general, these findings indicated that the study of new quinoxaline-aryfuran derivatives as inhibitors of STAT3 may lead to new therapeutic medical applications for cancer in the future.

SAR Study and Molecular Mechanism Investigation of Novel Naphthoquinone-furan-2-cyanoacryloyl Hybrids with Antitumor Activity.

A series of novel naphthoquinone-furan-2-cyanoacryloyl hybrids were designed; they were synthesized and preliminarily evaluated for their anti-proliferative activities in vitro against several cancer cell lines and normal cells. The most potent compound, 5c, inhibited the proliferation of HeLa cells (IC50 value of 3.10 ± 0.02 µM) and colony survival, and it induced apoptosis while having relatively weaker effects on normal cells. Compound 5c also triggered ROS generation and accumulation, thus partially contributing to the observed cell apoptosis. A Western blotting analysis demonstrated that compound 5c inhibited the phosphorylation of STAT3. Furthermore, a biolayer interferometry (BLI) analysis confirmed that compound 5c had a direct effect on STAT3, with a KD value of 13.0 µM. Molecular docking showed that 5c specifically occupied the subpockets in the SH2 domain, thereby blocking the whole transmission signaling process. Overall, this study provides an important structural reference for the development of effective antitumor agents.

Design, synthesis, and evaluation of fluoroquinolone derivatives as microRNA-21 small-molecule inhibitors.

MicroRNA-21 (miRNA-21) is highly expressed in various tumors. Small-molecule inhibition of miRNA-21 is considered to be an attractive novel cancer therapeutic strategy. In this study, fluoroquinolone derivatives A1-A43 were synthesized and used as miRNA-21 inhibitors. Compound A36 showed the most potent inhibitory activity and specificity for miRNA-21 in a dual-luciferase reporter assay in HeLa cells. Compound A36 significantly reduced the expression of mature miRNA-21 and increased the protein expression of miRNA-21 target genes, including programmed cell death protein 4 (PDCD4) and phosphatase and tensin homology deleted on chromosome ten (PTEN), at 10 µM in HeLa cells. The Cell Counting Kit-8 assay (CCK-8) was used to evaluate the antiproliferative activity of A36; the results showed that the IC50 value range of A36 against six tumor cell lines was between 1.76 and 13.0 µM. Meanwhile, A36 did not display cytotoxicity in BEAS-2B cells (lung epithelial cells from a healthy human donor). Furthermore, A36 significantly induced apoptosis, arrested cells at the G0/G1 phase, and inhibited cell-colony formation in HeLa cells. In addition, mRNA deep sequencing showed that treatment with A36 could generate 171 dysregulated mRNAs in HeLa cells, while the expression of miRNA-21 target gene dual-specificity phosphatase 5 (DUSP5) was significantly upregulated at both the mRNA and protein levels. Collectively, these findings demonstrated that A36 is a novel miRNA-21 inhibitor.

Design and synthesis of N-(1-(6-(substituted phenyl)-pyridazin-3-yl)-piperidine-3-yl)-amine derivatives as JMJD6 inhibitors.

JMJD6 is a member of the JmjC domain-containing family and has been identified as a promising therapeutic target for treating estrogen-induced and triple-negative breast cancer. To develop novel anti-breast cancer agents, we synthesized a class of N-(1-(6-(substituted phenyl)-pyridazine-3-yl)-piperidine-3-yl)-amine derivatives as potential JMJD6 inhibitors. Among them, the anti-cancer compound A29 was an excellent JMJD6 binder (KD = 0.75 ± 0.08 µM). It could upregulate the mRNA and protein levels of p53 and its downstream effectors p21 and PUMA by inhibiting JMJD6. Besides, A29 displayed potent anti-proliferative activities against tested breast cancer cells by the induction of cell apoptosis and cell cycle arrest. Significantly, A29 also promoted a remarkable reduction in tumor growth, with a TGI value of 66.6% (50 mg/kg, i.p.). Taken together, our findings suggest that A29 is a potent JMJD6 inhibitor bearing a new scaffold acting as a promising drug candidate for the treatment of breast cancer.

Identification of Novel 4'-O-Demethyl-epipodophyllotoxin Derivatives as Antitumor Agents Targeting Topoisomerase II.

C4 variation of 4'-O-demethyl-epipodophyllotoxin (DMEP) is an effective approach to optimize the antitumor spectra of this compound class. Accordingly, two series of novel DMEP derivatives were synthesized, and as expected, the antitumor spectra of these derivatives varied with different C4 substituents. Notably, most compounds showed significant inhibition against the etoposide (2)-resistant KBvin cells. Four of the compounds (11, 18, 27 and 28) induced protein-linked DNA break (PLDB) levels higher than those of GL-331 (6) and 2, and are assumed to be topoisomerase II (topo II) poisons more potent than 6 and 2. Compound 28, a potent topo II poison highly effective against KBvin cells, was further evaluated with a panel of tumor cells and was most active against HepG2. This compound also exhibited apparent in vivo antitumor efficacy in hepatoma 22 (H22) mouse model. The results indicated that C4 derivation of DMEP is a feasible approach to identify potent topo II inhibitors with optimized antitumor profiles.

Design,synthesis,and evaluation of fluoroquinolone derivatives as microRNA-21 small-molecule inhibitors / 药物分析学报

MicroRNA-21(miRNA-21)is highly expressed in various tumors.Small-molecule inhibition of miRNA-21 is considered to be an attractive novel cancer therapeutic strategy.In this study,fluoroquinolone de-rivatives Al-A43 were synthesized and used as miRNA-21 inhibitors.Compound A36 showed the most potent inhibitory activity and specificity for miRNA-21 in a dual-luciferase reporter assay in HeLa cells.Compound A36 significantly reduced the expression of mature miRNA-21 and increased the protein expression of miRNA-21 target genes,including programmed cell death protein 4(PDCD4)and phos-phatase and tensin homology deleted on chromosome ten(PTEN),at 10 uM in HeLa cells.The Cell Counting Kit-8 assay(CCK-8)was used to evaluate the antiproliferative activity of A36;the results showed that the IC50 value range of A36 against six tumor cell lines was between 1.76 and 13.0 μM.Meanwhile,A36 did not display cytotoxicity in BEAS-2B cells(lung epithelial cells from a healthy human donor).Furthermore,A36 significantly induced apoptosis,arrested cells at the G0/G1 phase,and inhibited cell-colony formation in HeLa cells.In addition,mRNA deep sequencing showed that treatment with A36 could generate 171 dysregulated mRNAs in HeLa cells,while the expression of miRNA-21 target gene dual-specificity phosphatase 5(DUSP5)was significantly upregulated at both the mRNA and protein levels.Collectively,these findings demonstrated that A36 is a novel miRNA-21 inhibitor.