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Targeting the lysine residue of protein kinases to develop covalent inhibitors is an emerging hotspot. Herein, we have reported an approach to develop lysine-targeted covalent inhibitors of PI3Kδ by in situ interaction upgradation of the H-bonding to covalent bonding. Several warhead groups were introduced and screened in situ, leading to lysine-targeted covalent inhibitors bearing aromatic esters with high bioactivity and PI3Kδ selectivity. Compound A11 bearing phenolic ester was finally optimized to show a long duration of action in SU-DHL-6 cells by multiple assays. Docking simulation and further protein mass spectrometry confirmed that A11 bound to PI3Kδ by covalent-bonding interactions with Lys779. Furthermore, A11 exhibited potently antitumor efficacy without obvious toxicity in the SU-DHL-6 and Pfeiffer xenograft mouse models. This study identified A11 to be a much more effective antitumor agent in vitro and in vivo as a lysine-targeted covalent inhibitor, and it also provided a practical approach for the development of lysine-targeted covalent inhibitors.

Aim: In our study compounds with pyrido[3,2- d ]pyrimidine and pyrido[3,4- d ]pyrimidine were designed, synthesized and evaluated for their biological activity against hematologic tumors. Methods: The biological activity of compounds was evaluated by ADP-Glo Luminescence assay, MTT [3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide] assay, western blotting and flow cytometry, respectively. Results: Compounds A1 , A5 and A7 containing pyrido[3,2- d ]pyrimidine inhibited phosphoinositide 3-kinase-δ (PI3Kδ) at subnanomolar levels and had good δ-isoform selectivity. A1 , A5 and A7 showed significant inhibitory effects against SU-DHL-6 cells and effectively inhibited Akt phosphorylation in a good concentration-dependent manner. A7 induced apoptosis and caused cell cycle arrest in SU-DHL-6 cells. Docking studies showed that A1 , A5 and A7 bound tightly to PI3Kδ through key hydrogen bonding interactions. Conclusion: This study suggests that employing pyrido[3,2- d ]pyrimidine can facilitate the design of novel potent and selective PI3Kδ inhibitors.

The clinical use of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) in the treatment of non-small cell lung cancer was limited by the drug resistance caused by EGFR C797S mutation. Therefore, in order to overcome the drug resistance, we designed and synthesized a series of 2-aminopyrimidine derivatives as EGFR C797S -TKIs. Among these compounds, compounds A5 and A13 showed significant anti-proliferative activity against the KC-0116 (EGFR del19/T790M/C797S ) cell line with high selectivity. A5 inhibited EGFR phosphorylation and induced apoptosis of KC-0116 cell, arrested KC-0116 cell at G2/M phase. Molecular docking results showed that A5 and brigatinib bind to EGFR in a similar pattern. In addition to forming two important hydrogen bonds with Met793 residue, A5 also formed a hydrogen bond with Lys745 residues, which may play an important role for the potent inhibitory activity against EGFR del19/T790M/C797S . Based on these results, A5 turned out to be effective reversible EGFR C797S -TKIs which can be further developed., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

As oncogene c-MYC is abnormally expressed during TNBC pathogenesis, stabilizing its promoter G-quadruplex (G4), which may thus inhibit c-MYC expression and promote DNA damage, may be a potential anti-TNBC strategy. However, large quantities of potential G4-forming sites exist in the human genome, which represents a potential drug selectivity problem. In order to achieve better recognition for c-MYC G4, we herein presented a new approach of designing small-molecule ligands by linking tandem aromatic rings with the c-MYC G4 selective binding motifs. Thus, a series of non-fused, conformation-tunable imidazole-biphenyl analogs were designed and synthesized. Among them, the optimal ligand appeared more effective on stabilizing c-MYC G4 than other types of G4s possibly through an adaptive, multi-site binding mode involved of end-stacking, groove-binding and loop-interacting. Then, the optimal ligand exerted good inhibitory activity on c-MYC expression and induced remarkable DNA damage, leading to the occurrence of G2/M phase arrest, apoptosis and autophagy. Furthermore, the optimal ligand exhibited potent antitumor effects in a TNBC xenograft tumor model. To sum up, this work offers new insights for the development of selective c-MYC G4 ligands against TNBC., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Aim: ZCJ14, a gefitinib analog, exhibited prominent anti-cancer effect both in vitro and in vivo. The present study aims to investigate the inhibitory effects of ZCJ14 on human cancer cells, and explored its possible mechanism of action., Main Methods: The inhibitory effect of ZCJ14 on human-derived tumor cells in vitro was mainly measured by MTT and colony formation assays. The nude mouse xenograft models were established to figure out the inhibitory effect of ZCJ14 on solid tumors in vivo. Western blotting assays were used to detect the phosphorylation level of EGFR down-streaming proteins and the proteomic technique was used to study the proteome alterations of cancer cells triggered by ZCJ14., Key Findings: ZCJ14 inhibited the proliferation of A549 (lung cancer), HCT116 (colorectal cancer) and MCF-7 (breast cancer) cells in vitro with 48 h IC 50 values of 0.83, 0.85 and 0.92 μM, respectively. It suppressed the growth of A549, NCI-H1975, NCI-H1299 and MCF-7, HCT116 tumors in mouse xenograft models, and had almost no toxicity. At the same dose, the inhibitory effect of ZCJ14 on solid tumors was better than the corresponding positive drugs. ZCJ14 does not exert anti-tumor effects through inhibition of EGFR pathway, but by enhancing steroid biosynthesis and inhibiting ubiquitin-mediated proteolysis., Significance: Based on the excellent anti-tumor effect of ZCJ14 on human tumor cell lines, it can be used as an effective anti-tumor drug candidate. In addition, the results of proteomic study in this paper can provide clues for further study of the anti-tumor mechanism of ZCJ14., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

MicroRNA-21 is a carcinogenic microRNA, whose overexpression arises in a variety of tumor tissues. Hence, microRNA-21 a prospective target for cancer treatment, and regulation of microRNA-21 by small molecule inhibitors is deemed as a promising approach for tumor therapy. In this work, to discover potent microRNA-21 inhibitor, series of 4-(N-norfloxacin-acyl)aminobenzamides were designed and synthesized, and their inhibitory effects were appraised by utilizing dual luciferase reporter assays. The results indicated that compound A7 was the most efficient microRNA-21 small molecule inhibitor. What's more, A7 suppressed the migration of Hela cells and the colony formation of Hela and HCT-116 cells as well as promoted apoptosis of Hela cells. In the mechanism study, results of RT-qPCR certified that A7 could reduce the level of mature microRNA-21 via disrupting its expression at the transcriptional level of its primary form "pri-miR-21", which was distinct from most previous inhibitors directly binding with pre-miR-21. Noticeably, Western blotting and RT-qPCR uncovered A7 could upregulate the expression PTEN, EGR1 and SLIT2, which are the downstream functional targets of microRNA-21. These findings demonstrated that A7 was a promising microRNA-21 small molecule inhibitor and 4-(N-norfloxacin-acyl) aminobenzamide can serve as a new scaffold for discovery of potent microRNA-21 inhibitor., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Introduction: Chromosomal translocations involving the mixed-lineage leukemia (MLL, KMT2A, MLL1) genes result in the production of MLL fusion proteins, which cause abnormal transcriptional regulation leading to acute leukemia (AL). Menin (MEN1) protein is essential for MLL to regulate the expression of related target genes. High-affinity interactions between the amino terminus of MLL proteins and Menin proteins are required to mediate the oncogenic transformation of MLL fusion proteins. Therefore, inhibition of Menin and MLL interaction is a potential therapeutic strategy for MLL rearrangement (MLL-r) leukemia and can provide a new choice for treatment of other diseases. Therefore, researchers have made great efforts to explore small-molecule Menin-MLL interaction inhibitors., Areas Covered: This review is to provide an overview of the patented Menin-MLL protein-protein interaction inhibitors from 2014 to 2021., Expert Opinion: Menin-MLL interaction inhibitors have therapeutic potential in the treatment of acute leukemia, such as AML and ALL. SNDX-5613 and KO-539 have been granted orphan drug designation by the FDA for treatment of refractory/relapsed leukemia and AML, respectively. In addition, they are undergoing clinical evaluation for other indications. It is clear that Menin-MLL interaction inhibitors have promising benefits in the clinical treatment of leukemia and other diseases.

Drug resistance caused by epidermal growth factor receptor (EGFR) mutation has largely limited the clinical use of EGFR tyrosine kinase inhibitors (EGFR-TKIs) for the treatment of non-small-cell lung cancer (NSCLC). Herein, to overcome the intractable problem of drug resistance, proteolysis targeting chimeras (PROTACs) targeting EGFR mutants were developed by optimizing covalent EGFR ligands. Covalent or reversible covalent pyrimidine- or purine-containing PROTACs were designed, synthesized, and evaluated. As a consequence, covalent PROTAC CP17 , with a novel purine-containing EGFR ligand, was discovered as a highly potent degrader against EGFR L858R/T790M and EGFR del19 , reaching the lowest DC 50 values among all reported EGFR-targeting PROTACs. Furthermore, CP17 exhibited excellent cellular activity against the H1975 and HCC827 cell lines with high selectivity. Mechanism investigation indicated that the lysosome was involved in the degradation process. Importantly, the covalent binding strategy was proven to be an effective approach for the design of PROTACs targeting EGFR L858R/T790M , which laid the practical foundation for further development of potent EGFR-targeting PROTACs.

Purpose: The overall response of cisplatin-based chemotherapy in bladder urothelial carcinoma (BUC) remains unsatisfactory due to the complex pathological subtypes, genomic difference, and drug resistance. The genes that associated with cisplatin resistance remain unclear. Herein, we aimed to identify the cisplatin resistance associated genes in BUC. EXPERIMENTAL DESIGN: The cytotoxicity of cisplatin was evaluated in six bladder cancer cell lines to compare their responses to cisplatin. The T24 cancer cells exhibited the lowest sensitivity to cisplatin and was therefore selected to explore the mechanisms of drug resistance. We performed genome-wide CRISPR screening in T24 cancer cells in vitro, and identified that the gene heterogeneous nuclear ribonucleoprotein U (HNRNPU) was the top candidate gene related to cisplatin resistance. Epigenetic and transcriptional profiles of HNRNPU-depleted cells after cisplatin treatment were analyzed to investigate the relationship between HNRNPU and cisplatin resistance. In vivo experiments were also performed to demonstrate the function of HNRNPU depletion in cisplatin sensitivity., Results: Significant correlation was found between HNRNPU expression level and sensitivity to cisplatin in bladder cancer cell lines. In the high HNRNPU expressing T24 cancer cells, knockout of HNRNPU inhibited cell proliferation, invasion, and migration. In addition, loss of HNRNPU promoted apoptosis and S-phase arrest in the T24 cells treated with cisplatin. Data from The Cancer Genome Atlas (TCGA) demonstrated that HNRNPU expression was significantly higher in tumor tissues than in normal tissues. High HNRNPU level was negatively correlated with patient survival. Transcriptomic profiling analysis showed that knockout of HNRNPU enhanced cisplatin sensitivity by regulating DNA damage repair genes. Furthermore, it was found that HNRNPU regulates chemosensitivity by affecting the expression of neurofibromin 1 (NF1)., Conclusions: Our study demonstrated that HNRNPU expression is associated with cisplatin sensitivity in bladder urothelial carcinoma cells. Inhibition of HNRNPU could be a potential therapy for cisplatin-resistant bladder cancer., (© 2022. The Author(s).)

Cancer immunotherapy is a strategy that is moving to the frontier of cancer treatment in the current decade. In this study, we show evidence that 3-(2-nitrophenyl) propionic acid-paclitaxel nanoparticles (NPPA-PTX NPs), act as immunogenic cell death (ICD) inducers, stimulating an antitumor response which results in synergistic antitumor activity by combining anti-PD-L1 antibody (aPD-L1) in vivo . To investigate the antitumor immunity induced by NPPA-PTX NPs, the expression of both ICD marker calreticulin (CRT) and high mobility group box 1 (HMGB1) were analyzed. In addition, the antitumor activity of NPPA-PTX NPs combined with aPD-L1 in vivo was also investigated. The immune response was also measured through quantitation of the infiltration of T cells and the secretion of pro-inflammatory cytokines. The results demonstrate that NPPA-PTX NPs induce ICD of MDA-MB-231 and 4T1 cells through upregulation of CRT and HMGB1, reactivating the antitumor immunity via recruitment of infiltrating CD3+, CD4+, CD8+ T cells, secreting IFN-γ, TNF-α, and the enhanced antitumor activity by combining with aPD-L1. These data suggest that the combined therapy has a synergistic antitumor activity and has the potential to be developed into a novel therapeutic regimen for cancer patients.

Mixed lineage leukemia (MLL) gene rearrangements are associated with acute leukemia. The protein menin is regarded as a critical oncogenic cofactor of the resulting MLL fusion proteins in acute leukemia. A direct interaction between menin and the MLL amino terminal sequences is necessary for MLL fusion protein-mediated leukemogenesis. Thus, inhibition of the interaction between menin and MLL has emerged as a novel therapeutic strategy. Recent improvements in structural biology and chemical reactivity have promoted the design and development of selective and potent menin-MLL interaction inhibitors. In this Perspective, different classes of menin-MLL interaction inhibitors are comprehensively summarized. Further research potential, challenges, and opportunities in the field are also discussed.

Selenium (Se) is an essential micronutrient of organism and has important function. It participates in the functions of selenoprotein in several manners. In recent years, Se has attracted much attention because of its therapeutic potential against several diseases. Many natural and synthetic organic Se-containing compounds were studied and explored for the treatment of cancer and other diseases. Studies have showed that incorporation of Se atom into small molecules significantly enhanced their bioactivities. In this paper, according to different applications and structural characteristics, the research progress and therapeutic application of Se-containing compounds are reviewed, and more than 110 Se-containing compounds were selected as representatives which showed potent activities such as anticancer, antioxidant, antifibrolytic, antiparasitic, antibacterial, antiviral, antifungal and central nervous system related effects. This review is expected to provide a basis for further study of new promising Se-containing compounds., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

The angucylines are a family of aromatic polyketides featuring a tetracyclic benz[a]anthraquinone skeleton. This class of polycyclic aromatic polyketides are exclusively associated with actinomycetes and can undergo many modifications such as oxidation, ring cleavage, glycosylation and dimerization. Here we report the discovery of a new ether-linked benz[a]anthraquinone heterodimer, named mycolatone (1), from a grasshopper-derived actinomycete, Amycolatopsis sp. HCa1. The structure of mycolatone (1) was determined by comprehensive two-dimensional NMR analysis, high-resolution electrospray ionization mass spectrometry and biogenetic consideration. This new heterodimeric molecule is structurally derived from the dimerization of two tetracyclic angucylines, 2-hydroxy-5-O-methyltetragomycin and PD116779, through an ether bond between C-8 and C-8'. This new structural feature enrich the structural diversity of angucylines. Additionally, the surface tension activity and cytotoxic activities of 1 against human cervical cancer cell line (Hela), human gastric adenocarcinoma cell line (SGC-7901) and human lung adenocarcinoma cell line (SPC-A-1) were evaluated., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Despite remarkable clinical achievements, camptothecin (CPT) still suffers from poor solubility and severe toxicity. Therefore, it is necessary to redevelop CPT derivatives as supplementary antitumor agents with good water solubility and small side effects. In this work, 27 camptothecin derivatives were synthesized and screened for their cytotoxicity against A549 (lung) and HCT-116 (colon) cancer cell lines. Among them, compound B7, 7-ethyl-10-(2-oxo-2-(4-methylpiperidin-1-yl)ethoxy)camptothecin,was demonstrated in vitro to be a more potent antitumor agent than SN-38 by comparison of their inhibitory activities against cell proliferation and colony formation and interference effect on process of cell cycle and cell apoptosis. Additionally, a molecular docking model revealed that B7 can interact with the topoisomerase I-DNA complex, and that the solubility of B7 reached 5.73 μg/mL in water. Moreover, B7 significantly inhibited tumor growth in an A549 xenograft model at dosages of 0.4 and 2.0 mg/kg, and exhibited minimum lethal doses comparable to those of irinotecan. These results indicated that B7, with improved solubility, enhanced activity and acceptable acute toxicity, can be used as a lead compound for the development of novel anticancer agents., (© 2020 Wiley-VCH GmbH.)

Epidermal growth factor receptor (EGFR) is an important therapeutic target for the treatment of non-small cell lung cancer. A number of efficacious EGFR tyrosine kinase inhibitors have been developed. However, acquired drug resistance largely encumbered their clinical practicability. Therefore, there is an urgent need to develop new therapeutic regime. Herein, we designed and synthesized a set of EGFR-targeting small molecule PROTACs which showed promising efficacy. In particular, VHL-recruiting compound P3 showed potent anti-proliferative activity against HCC827 and H1975 cell lines with IC 50 values of 0.83 and 203.01 nM, respectively. Furthermore, both EGFR del19 and EGFR L858R/T790M could be significantly induced to be degraded under treatment of P3 with DC 50 values of 0.51 and 126.2 nM, respectively. Compound P3 was able to dramatically suppress EGFR pathway signal transduction. Moreover, compound P3 could significantly induce cell apoptosis, arrest cell cycle and suppress cell colony formation. In addition, we identified that ubiquitination was indispensable in the degradation process, and found that the degradation was related to autophagy. Our work would provide an alternative approach for development of potentially effective EGFR degraders and give a new clue for investigation of PROTAC-induced protein degradation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

The PI3K pathway is aberrantly activated in many cancers and plays a critical role in tumour cell proliferation and survival, making it a rational therapeutic target. In the present study, the effects and the underlying mechanism of a new PI3K inhibitor, W941, were investigated in non-small-cell lung cancer (NSCLC). The results of this study showed that W941 inhibited the growth of A549 and Hcc827 cells with IC 50 values of 0.12 and 0.23 μM, respectively, and that W941 markedly inhibited the growth of A549 xenograft tumours in a nude mouse model without decreasing body weight. Western blotting assays showed that W941 inhibited the phosphorylation of downstream proteins in the PI3K pathway (AKT, mTOR, p70S6K and 4EBP1) in both A549 and Hcc827 cells. In addition, after W941 treatment, a dose-dependent increase in the ratio of the LC3-II/I ratio was observed. When cells were pre-treated with chloroquine or bafilomycin A1, W941 increased the LC3-II/I ratio, suggesting that W941 acted as an autophagy inducer. Moreover, autophagy blockers enhanced apoptosis after W941 treatment, indicating that W941-induced autophagy actually protected the cells against its cytotoxicity. Our findings suggest that the combination of a PI3K inhibitor with an autophagy inhibitor might be a novel option for NSCLC treatment.

Topoisomerases are interesting targets for drug discovery. In the present study, we attached saturated carbon atoms to the 10-position of camptothecin and synthesized 10 new camptothecin derivatives from 10-HCPT or SN-38. The activities of new compounds were evaluated both in vitro and in vivo. The most promising compound F10, 7-ethyl-10-(2-oxo-2-(piperidin-1-yl)ethoxy)camptothecin, inhibited cancer cells growth with the IC 50 of 0.002, 0.003, 0.011 and 0.081 μM on Raji, HCT116, A549 and Lovo cells, respectively. Meanwhile, oral administration of F10 remarkably suppressed the HCT116-xenograft tumor growth in the nude-mice model at the dosage of 0.5, 2.0 and 8.0 mg/kg in vivo. Intraperitoneal administration of F10 can completely inhibit Raji-xenograft tumor growth in established NPG mouse model at 2.0 and 4.0 mg/kg. In addition, the minimum lethal doses of F10 and SN-38 in mice by intravenous administration were 80 and 40 mg/kg (or 0.155, 0.102 mmol/kg), respectively. The solubility of F10 reached 9.86 μg/mL in a buffer solution of pH 4.5. The oral bioavailability of F10 achieved 22.4% in mice. The molecular docking model revealed that F10 can interact with topoisomerase I-DNA complex. Our findings indicate that F10 is a new orally-oavailable antitumor agent with potent anticancer effect. Furthermore, attaching a ring hydrophobic moiety to the 10-position of camptothecin provides a favorable approach in the optimization of camptothecin., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Epidermal growth factor receptor (EGFR), a member of the HER family, is closely related to the development of multiple cancers. Herein, we report the discovery of small molecule EGFR degraders based on the proteolysis targeting chimera (PROTAC) strategy. In the present study, 13 EGFR degraders containing pyrido[3,4-d] pyrimidine moiety were designed and synthesized. Promising PROTACs 2 and 10 induced degradation of EGFR in HCC827 cells with the DC 50 values of 45.2 and 34.8 nM, respectively. Cellular protein-controlling machinery ubiquitin proteasome system (UPS) was involved in the degradation process. Furthermore, the degraders 2 and 10 could significantly induce the apoptosis of HCC827 cells and arrest the cells in G 1 phase. These findings demonstrated that compounds 2 and 10 could serve as effective EGFR del19 -targeting degraders in HCC827 cells. v., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Targeting L858R/T790M/C797S mutant EGFR is a major challenge in the new-generation EGFR tyrosine kinase inhibitors development for conquering drug resistant NSCLC. In this study, a series of novel 9-heterocyclyl substituted 9H-purine derivatives were designed as EGFR L858 R/T790 M/C797S tyrosine kinase inhibitors. Among these compounds, D4, D9, D11 and D12 showed significantly potent anti-proliferation and EGFR L858 R/T790 M/C797S inhibition activity. In particular, the most potent compound D9 showed anti-proliferation against HCC827 and H1975 cell lines with the IC 50 values of 0.00088 and 0.20 μM, respectively. And D9 inhibited the EGFR L858 R/T790 M/C797S with an IC 50 value of 18 nM. Furtherly, D9 could significantly suppress the EGFR phosphorylation, induce the apoptosis, arrest cell cycle at G0/G1, and inhibit colony formation in HCC827 cell line by a concentration-dependent manner. Molecular docking indicated that the introduction of a cyclopropylsulfonamide group in D9 led to the formation of additional two hydrogen bonds with mutant Ser797 which played key roles in generating efficient EGFR L858 R/T790 M/C797S inhibitory activity. These findings strongly indicated that 9-heterocyclyl substituted 9H-purine derivatives were promising L858R/T790M/C797S mutant EGFR-TKIs. The introduction of extra hydrogen bond interaction with mutant Ser797 is efficient method for the design of the fourth-generation EGFR-TKIs., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Ruthenium complexes have stood out by several mononuclear complexes which have entered into clinical trials, such as imidazolium [trans-RuCl4(1H-imidazole)(DMSO-S)] (NAMI-A) and ([Ru(II)(4,4'-dimethyl-2,2'-bipyridine)2-(2(2'-,2'':5'',2'''-terthiophene)-imidazo[4,5-f] [1,10]phenanthroline)] 2+) (TLD-1433), opening a new avenue for developing promising ruthenium-based anticancer drugs alternative to Cisplatin. Polynuclear ruthenium complexes were reported to exhibit synergistic and/or complementary effects: the enhanced DNA structural recognition and DNA binding as well as in vitro anticancer activities. This review overviews some representative polynuclear ruthenium complexes acting as DNA structural probes, DNA binders and in vitro anticancer agents, which were developed during last decades. These complexes are reviewed according to two main categories of homo-polynuclear and hetero-polynuclear complexes, each of which is further clarified into the metal centers linked by rigid and flexible bridging ligands. The perspective, challenges and future efforts for investigations into these exciting complexes are pointed out or suggested., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Near-IR-emitting and/or efficiently photodynamic water-soluble Ru(II) complexes that hold great application potentials as photodynamic therapy and/or photodetection agents for cancers have been poorly explored. In this paper, the solvatochromism, calf thymus DNA binding, and singlet oxygen generation properties of a known ruthenium(II) complex of visible-emitting [Ru(bpy) 2 (dtdpq)](ClO 4 ) 2 ( Ru1 ) and a new homoleptic complex of near-IR-emitting [Ru(dtdpq) 3 ](ClO 4 ) 2 ( Ru2 ) (bpy = 2,2'-bipyridine, dtdpq = 2,3-bis(thiophen-2-yl)pyrazino[2,3- f ][1,10]phenanothroline) in water are reported. Moreover, DNA photocleavage, singlet oxygen generation in HeLa cells, cellular uptake/localization, and in vitro photodynamic therapy for cancer cells of water-soluble Ru1 are described in detail. The results show that Ru1 acted as potent photodynamic cancer therapy and mitochondrial imaging agents. Ru2 exhibited very strong solvatochromism from a visible emission maximum at 588 nm in CH 2 Cl 2 to the near-IR region at 700 nm in water and singlet oxygen generation yield in water (23%) and DNA binding properties (intercalative DNA binding constant on the order of 10 6 M -1 ) comparable to those of Ru1 , which should make Ru2 attractive for the aforementioned applications of Ru1 if the water solubility of Ru2 can be improved enough for the studies above.

Phosphoinositide 3-kinases (PI3Ks) are regarded as promising targets for treatment of various cancers due to their roles in regulating cell proliferation, differentiation, migration, and survival. Here we report our efforts to develop potent and orally bioavailable PI3K inhibitors for the treatment of cancers. The alkylsulfonamide-containing quinazoline derivatives A1-A18 significantly inhibited PI3Kα, and cell proliferation among HCT-116, MCF-7 and SU-DHL-6 cell lines. The optimal compound A1 displayed potent inhibitory activity against PI3Kα (IC 50  = 4.5 nM), PI3Kβ (IC 50  = 4.5 nM), PI3Kγ (IC 50  = 4.5 nM), PI3Kδ (IC 50  = 4.5 nM) and significantly inhibited the growth of HCT-116, MCF-7 and SU-DHL-6 cell lines with IC 50 values of 0.82 µM, 0.99 µM and 0.19 µM, respectively. Western blot analysis demonstrated A1 significantly suppressed the phosphorylation of AKT S473 in a dose-dependent manner. Furthermore, A1 could markedly inhibit cancer growth at the dose of 25 mg/kg in nude mouse HCT-116 xenograft model in vivo without causing significant weight loss or toxicity., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Small-molecule targeted antitumor drugs are considered to be a promising treatment that can improve the efficacy and reduce side effects. PI3K/Akt signaling pathway is constantly activated in various cancers. We recently synthesized a series of novel compounds of PI3K/Akt pathway inhibitors and found the most effective analog to be W934. In this study, we explored the in-vitro and in-vivo antitumor effects of W934 on A549 non-small-cell lung cancer cells and HCT116 colorectal cancer cells. In-vitro assays showed that W934 caused an inhibition of PI3Kα kinase. W934 can significantly suppress the viability of A549 and HCT116 cells with IC50 values of 0.25 and 0.23 μmol/l, respectively. Besides, the inhibitory effects on cell migration, invasion and apoptosis were also observed after treatment of W934 for the indicated hours. According to the cell cycle analysis, W934 caused an inhibition of G0-G1 phase progression and correspondingly decreased the percentage of cells in S and G2-M phases. Results of western blotting indicated that W934 concentration dependently suppressed the activation of the PI3K/Akt pathway. Meanwhile, the in-vivo effect was studied in an A549 xenograft mouse model. Oral administration of W934 inhibited the tumor growth in a dose-dependent manner. Hereby, W934 might be considered as a potential therapeutic drug candidate for non-small-cell lung cancer treatment.

In present study, we described the synthesis and biological evaluation of a new class of EGFR inhibitors containing 2,9-disubstituted 8-phenylthio/phenylsulfinyl-9H-purine scaffold. Thirty-one compounds were synthesized. Among them, compound C9 displayed the IC 50 of 29.4 nM against HCC827 cell line and 1.9 nM against EGFR L858R . Compound C12 showed moderate inhibitory activity against EGFR L858R/T790M/C797S (IC 50  = 114 nM). Western bolt assay suggested that compound C9 significantly inhibited EGFR phosphorylation. In vivo test, compound C9 remarkably exhibited inhibitory effect on tumor growth at 5.0 mg/kg by oral administration in established nude mouse HCC827 xenograft model. These results indicate that the 2,9-disubstituted 8-phenylsulfinyl/phenylsulfinyl-9H-purine derivatives can act as potent EGFR(L858R) inhibitors and effective anticancer agents. Additionally, optimization of compound C12 may result in discovering the fourth-generation EGFR-TKIs., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Targeting acquired drug resistance is the major challenge in the treatment of EGFR-driven non-small cell lung cancer (NSCLC). In this study, a novel class of compounds containing pyrido[3,4-d]pyrimidine scaffold was designed as new generation EGFR-TKIs to overcome this challenge. The most promising compound B30 inhibited HCC827 and H1975 cells growth with the IC 50 values of 0.044 μM and 0.40 μM, respectively. Meanwhile, B30 displayed potent inhibitory activity against the EGFR L858R (IC 50  = 1.1 nM) and EGFR L858R/T790M/C797S (IC 50  = 7.2 nM). B30 could suppress EGFR phosphorylation in a dose-dependent manner in HCC827 cell line and significantly induce the apoptosis of HCC827 cells. Molecular docking indicated that the hydroxyl in B30 could form additional hydrogen bond with mutant Ser797. These findings strongly support our assumption that 2,4,6-trisubstitued pyrido[3,4-d] pyrimidine derivatives can serve as EGFR-TKIs. The predicted hydrogen bond interaction formed by a small molecule inhibitor with mutant Ser797 is available to design the fourth-generation EGFR-TKIs., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Icaritin (ICT) displays numerous pharmacological activities for the treatment of various cancers, osteoporosis, inflammation, and angiocardiopathy. The absorption, distribution, metabolism, and excretion of ICT still remain unknown. ICT was administered to rats at 2 mg/kg for intravenous injection or 40 mg/kg for oral route. Major metabolite of ICT was identified using quadrupole time-of-flight (Q-TOF), and ICT and its major metabolite were quantified in plasma, tissues, urine, faeces, and bile by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). A total of 24 metabolites of ICT in plasma were identified and mono C-7 glucuronide glucuronidated icaritin (GICT) was the major metabolite of ICT after oral administration. The absolute bioavailability of ICT was 4.33% although ICT was rapidly absorbed into the blood. For oral administration, concentrations of GICT at various time points was 6.38-8.81-fold higher than those of ICT, and the area under the curve (AUC) of GICT was about 8-fold higher than that of ICT, while AUC values of ICT and GICT were almost equal for intravenous injection. Approximately 65.7% ICT and 42.7% GICT were distributed in liver and kidney, respectively. Unabsorbed ICT was mainly excreted as the parent form in faeces with at least 60% of administered dose during 24 h, whereas absorbed ICT was predominantly excreted as GICT from urine with 2.74% of administered dose accounting for 63.28% of absorbed drug. ICT was rapidly absorbed into the blood although a large amount of ICT remained unabsorbed, and then rapidly and mainly metabolized to GICT. ICT mainly distributed in liver, while GICT predominantly distributed in kidney. Absorbed ICT and GICT were predominantly excreted via urine, and unabsorbed ICT was mainly excreted as the parent form in faeces. Copyright © 2017 John Wiley & Sons, Ltd., (Copyright © 2017 John Wiley & Sons, Ltd.)

B-Raf kinase has been identified as an important target in recent cancer treatment. In order to discover structurally diverse and novel B-Raf inhibitors (BRIs), a virtual screening of BRIs against ZINC database was performed by using a combination of pharmacophore modelling, molecular docking, 3D-QSAR model and binding free energy (ΔG bind ) calculation studies in this work. After the virtual screening, six promising hit compounds were obtained, which were then tested for inhibitory activities of A375 cell lines. In the result, five hit compounds show good biological activities (IC 50 <50μM). The present method of virtual screening can be applied to find structurally diverse inhibitors, and the obtained five structurally diverse compounds are expected to develop novel BRIs., (Copyright © 2017. Published by Elsevier Ltd.)

A series of 4,6-disubstituted quinazoline derivatives as potential PI3K inhibitors were designed and synthesized. All compounds exhibited significant anti-proliferative activities against HCT-116 and MCF-7 cell lines, and compounds A7, A9, and A11 displayed the most potent anti-proliferative activity against the HCT-116. Further PI3K inhibitory activity evaluation showed that compound A7 displayed high potency against PI3K enzymes. The in vivo anti-tumor study showed compound A7 can efficaciously inhibit tumor growth in a mice S-180 model. These results suggest that our designed compounds can serve as potent PI3K inhibitors and effective antitumor agents., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In present study, 4-anilinoquinazolines scaffold, arylurea and tertiary amine moiety were combined to design, synthesize gefitinib analogs and discover novel anticancer agents. A series of 4-anilinoquinazoline derivatives (1, 2, 3 and 4) bearing arylurea and tertiary amine moiety at its 6-position were synthesized. Their antiproliferative activities in vitro were evaluated via MTT assay against A431 cell and A549 cell. The SAR of the title compounds was discussed. The compounds 2d, 2i and 2j with potent antiproliferative activities were evaluated their inhibitory activity against EGFR-TK. Compound 2j displayed potent inhibitory activity against EGFR-TK. In addition, compound 2j, at 50 mg/kg, can completely inhibit cancer growth in established nude mouse A549 xenograft model in vivo. These results suggest that the 4-anilinoquinazoline derivatives bearing diarylurea and tertiary amino moiety at its 6-position can serve as anticancer agents and EGFR inhibitors., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In present study, a series of N-(2-methoxy-5-(3-substituted quinazolin-4(3H)-one-6-yl)-pyridin-3-yl)phenylsulfonamide were synthesized. Their antiproliferative activities in vitro were evaluated via MTT assay against HCT116 and MCF-7 cancer cell lines. The SAR of title compounds was discussed. The compounds (S)-C5 and (S)-C8 displayed potent inhibitory activity against PI3Ks and mTOR, especially against PI3Kα. In addition, compound (S)-C5 can efficaciously inhibit tumor growth in a mice S-180 model. These findings suggest that our designed compounds can serve as potent PI3K inhibitors and effective anticancer agents., (Copyright © 2015. Published by Elsevier Ltd.)

As a PI3K and mTOR dual inhibitor, N-(2-chloro-5-(2-acetylaminobenzo[d]thiazol-6-yl)pyridin-3-yl)-4-fluorophenylsulfonamide displays toxicity when orally administrated. In the present study, alkylurea moiety replaced the acetamide group in the compound and a series of 1-alkyl-3-(6-(2,3-disubstituted pyridin-5-yl)benzo[d]thiazol-2-yl)urea derivatives were synthesized. The antiproliferative activities of the synthesized compounds in vitro were evaluated against HCT116, MCF-7, U87 MG and A549 cell lines. The compounds with potent antiproliferative activity were tested for their acute oral toxicity and inhibitory activity against PI3Ks and mTORC1. The results indicate that the compound attached a 2-(dialkylamino)ethylurea moiety at the 2-positeion of benzothiazole can retain the antiproliferative activity and inhibitory activity against PI3K and mTOR. In addition, their acute oral toxicity reduced dramatically. Moreover, compound 2f can effectively inhibit tumor growth in a mice S180 homograft model. These findings suggest that 1-(2-dialkylaminoethyl)-3-(6-(2-methoxy-3-sulfonylaminopyridin-5-yl)benzo[d]thiazol-2-yl)urea derivatives can serve as potent PI3K inhibitors and anticancer agents with low toxicity., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In the present study, a series of m-(4-morpholinoquinazolin-2-yl)benzamides were designed, synthesized and characterized. The antiproliferative activities of the synthesized compounds were evaluated against two human cell lines (HCT-116 and MCF-7). Compounds with IC50 values below 4 μM were further evaluated against U-87 MG and A549 cell lines. Among these evaluated compounds, compound T10 displayed a remarkable antiproliferative effect in vitro. The hoechst staining assay showed that compound T10 caused morphological changes. The cell cycle and apoptosis assay further indicated that compound T10 can arrest HCT-116 cells in G2/M and G0/G1 phase and induce apoptosis. PI3K enzyme assays indicated that compounds T7 and T10 selectively inhibit PI3Kα. A Western bolt assay further suggested that compound T10 can block the PI3K/Akt/mTOR pathway. Moreover, compound T10 inhibited tumor growth on a mice S180 homograft model. These findings directly identify m-(4-morpholinoquinazolin-2-yl)benzamide derivatives as novel anticancer agents., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

The fragment of 2-substituted-3-sulfonylaminobenzamide has been proposed to replace the fragment of 2-substituted-3-sulfonylaminopyridine in PI3K and mTOR dual inhibitors to design novel anticancer agents based on bioisostere. The combination of the fragment of 2-substituted-3-sulfonylaminobenzamide with the fragment of 2-aminobenzothiazole or 2-aminothiazolo[5,4-b]pyridine, or 2-amino[1,2,4]triazolo[1,5-a]pyridine produced the novel structures of anticancer agents. As a result, nineteen target compounds were synthesized and characterized. Their antiproliferative activities in vitro were evaluated via MTT assay against four human cancer cell lines including HCT-116, A549, MCF-7 and U-87 MG. The SAR of target compounds was preliminarily discussed. Compound 1g with potent antiproliferative activity was examined for its effect on the AKT and p-AKT(473). The anticancer effect of 1g was evaluated in established nude mice HCT-116 xenograft model. The results suggested that compound 1g can block PI3K/AKT/mTOR pathway and significantly inhibit tumor growth. These findings strongly support our assumption that the fragment of benzamide can replace the pyridine ring in some PI3K and mTOR dual inhibitor to design novel anticancer agents., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

2-Substituted-3-sulfonamino-5-(quinazolin-6-yl or quinolin-6-yl)benzamides have been proposed as novel structures of PI3K inhibitors and anticancer agents based on bioisostere. In the present study, 2-substituted-3-sulfonamino-5-(4-morpholinoquinazolin-6-yl)benzamides and 2-methoxy-3-sulfonamino-5-(4-morpholinoquinolin-6-yl)benzamides were synthesized. Their antiproliferative activities in vitro were evaluated via MTT assay against four human cancer cell lines, including A549, HCT-116, U-87 MG and KB. The SAR of the title compounds was preliminarily discussed. Compound 1a with potent antiproliferative activity was tested for its inhibitory activity against PI3K and mTOR and its effect on the AKT and p-AKT(473). The anticancer effect of 1a was evaluated in established nude mice U-87 MG xenograft model. The results suggest that compound 1a can significantly inhibit PI3K/AKT/mTOR pathway and tumor growth. These findings strongly support the assumption that title compounds are potent PI3K inhibitors and anticancer agents., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

2-Aryl-8-hydroxy (or methoxy)-isoquinolin-1(2H)-one has been proposed as a novel scaffold of EGFR inhibitor based on scaffold hoping. In the present study, a series of 2-aryl-8-hydroxy (or methoxy)-isoquinolin-1(2H)-one derivatives were synthesized. Their antiproliferative activities in vitro were evaluated via MTT assay against two human cancer cell lines, including A431 and A549. The SAR of the title compounds was preliminarily discussed. The compounds with ideal inhibition were evaluated through ELISA-based EGFR-TK assay. Compound 6c showed the best activity against A431 and EGFR tyrosine kinase. These findings suggest that title compounds are EGFR inhibitors with novel structures., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Antibacterial peptides (ABPs) with cancer-selective toxicity have received much more attention as alternative chemotherapeutic agents in recent years. However, the basis of their anticancer activity remains unclear. The modification of cell surface glycosylation is a characteristic of cancer cells. The present study investigated the effect of glycosylation, in particular sialic acid, on the anticancer activity of ABPs. We showed that aurein 1.2, buforin IIb and BMAP-28m exhibited selective cytotoxicity toward MX-1 and MCF-7 breast cancer cells. The binding activity, cytotoxicity and apoptotic activity of ABPs were enhanced by the presence of O-, N-glycoproteins, gangliosides and sialic acid on the surface of breast cancer cells. Among N-, O-glycoproteins and ganglioside, O-glycoproteins almost had the strongest effect on the binding and cytotoxicity of the three peptides. Further, up-regulation of hST6Gal1 in CHO-K1 cells enhanced the susceptibility of cells to these peptides. Finally, the growth of MX-1 xenograft tumors in mice was significantly suppressed by buforin IIb treatment, which was associated with induction of apoptosis and inhibition of vascularization. These data demonstrate that the three peptides bind to breast cancer cells via an interaction with surface O-, N-glycoproteins and gangliosides. Sialic acids act as key glycan binding sites for cationic ABP binding to glycoproteins and gangliosides. Therefore, glycosylation in breast cancer cells plays an important role in the anticancer activity of ABPs, which may partly explain their cancer-selective toxicity. Anticancer ABPs with cancer-selective cytotoxicity will be promising candidates for anticancer therapy in the future., (Copyright © 2013 Elsevier Inc. All rights reserved.)

A series of [1,2,4]triazolo[1,5-a]pyridinylpyridines were synthesized and characterized. Their antiproliferative activities in vitro were evaluated by MTT against three human cancer cell lines including HCT-116, U-87 MG and MCF-7 cell lines. The SAR of target compounds was preliminarily discussed. The compounds 1c and 2d with potent antiproliferative activities were tested for their effects on the AKT and p-AKT(473). The anticancer effect of 1c was evaluated in mice bearing sarcoma S-180 model. The results suggest that the title compounds are potent anticancer agents., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

A series of conjugates of 5-Fluorouracil (5-FU) and emodin were synthesized by coupling trimethyl emodin with N(1), N(3) dialkylated 5-FU. The 5-FU moiety contained various substituents at the N(3)-position were linked to the 2-position of trimethyl emodin via a methylene linkage. Their cytotoxicity against three cancer cell lines and one noncancerous cell were studied. The results revealed that some of conjugates exhibited better or comparable in vitro antitumor activity to 5-FU and emodin and low toxicity in the normal cell. The structure-activity relationship study showed N(3)-aromatic substituent was important for their cytotoxic activity., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Some cationic antibacterial peptides exhibit a broad spectrum of cytotoxic activity against cancer cells, which could provide a new class of anticancer drugs. In the present study, the anticancer activity of ABP-CM4, an antibacterial peptide from Bombyx mori, against leukemic cell lines THP-1, K562 and U937 was evaluated, and the cytotoxicity compared with the effects on non-cancerous mammalian cells, including peripheral blood mononuclear cells (PBMCs), HEK-293 and erythrocytes. ABP-CM4 reduced the number of viable cells of the leukemic cell lines after exposure for 24h. The reduction was concentration dependent, and the IC50 values ranged from 14 to 18 microM. Conversely, ABP-CM4, even at 120 microM, exhibited no cytotoxicity toward HEK-293 or PBMCs, indicating that there was no significant effect on these two types of non-cancer cells. ABP-CM4 at a concentration of 200 microM had no hemolytic activity on mammalian erythrocytes. Together, these results suggested a selective cytotoxicity in leukemia cells. Flow cytometry demonstrated that the binding activity of ABP-CM4 to leukemia cells was much higher than that to HEK-293 or PBMCs, and there was almost no binding to erythrocytes. FITC-labeled ABP-CM4 molecules were examined under a confocal microscope and found to be concentrated at the surface of leukemia cells and changes of the cell membrane were determined by a cell permeability assay, which led us to the conclusion that ABP-CM4 could act at the cell membrane for its anticancer activity on leukemia cells. Collectively, our results indicated that ABP-CM4 has the potential for development as a novel antileukemic agent., (Copyright 2010 Elsevier Inc. All rights reserved.)

Human interferon alpha2b (IFN-alpha2b) is a pleiotropic cytokine used for the treatment of various cancers. Antibacterial peptide CM4 is a small peptide that can strongly inhibit many kinds of bacteria, fungi, and tumor cells, but it does no harm to normal cells. Here, we describe a protein expression system for the production of IFN-alpha2b/CM4 fusion protein in insoluble form in Escherichia coli, coupled to an efficient dialysis refolding and histidine-tag purification protocol. The expressed IFN-alpha2b/CM4 fusion protein not only displays significantly improved antitumor activity, but also retains the antibacterial-antifungal activity of CM4., (Copyright 2009 Elsevier GmbH. All rights reserved.)