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Table S1: Enzymatic activities of SKLB261 against recombinant human protein kinases. Table S2: IC50 values (microM) for inhibition of cell growth after treatment with SKLB261, gemcitabine, erlotinib, dasatinib, or sunitinib for 72 h. Table S3: Pharmacokinetic parameters for SKLB261 in Sprague−Dawley rats. Table S4: Analysis of statistical significance of animal survival after treatment with SKLB261 or other agents. Figure S1: Growth inhibition of pancreatic tumor cell lines after treatment with SKLB261, dasatinib, gemcitabine, erlotinib, or sunitinib. Figure S2: The effect of SKLB261 treatment on tumor weight and body weight of mice with human pancreatic tumor xenografts. Figure S3: Antitumor efficacy of SKLB261 in PANC-1 tumor xenografts. Figure S4: Effect of SKLB261 on tumor angiogenesis in vivo. Figure S5: The effect of SKLB261 on tumor angiogenesis after treatment for 3 days or 5 days. Figure S6: Anti-metastatic activities of SKLB261 against pancreatic cancer cells in vitro.

Anti-epidermal growth factor receptor (EGFR) treatment has been successfully applied in clinical cancer therapy. However, the clinical efficacy of first-generation reversible EGFR inhibitors, such as gefitinib and erlotinib, is limited by the development of drug-resistant mutations, including the gatekeeper T790M mutation and upregulation of alternative signaling pathways. Second-generation irreversible EGFR inhibitors that were designed to overcome the drug resistance due to the T790M mutation have thus far had limited success. Here, we report a novel reversible EGFR inhibitor, SKLB1206, which has potent activity against EGFR with gefitinib-sensitive and -resistant (T790M) mutations. In addition, SKLB1206 has also considerable inhibition potency against some other related oncokinases, including ErbB2, ErbB4, and VEGF receptor 2 (VEGFR2). SKLB1206 exhibited highly antiproliferative activity against a range of EGFR-mutant cell lines, including gefitinib-sensitive and -resistant cell lines, and EGFR or ErbB2-overexpressing cell lines. SKLB1206 also showed a potent antiangiogenesis effect in vitro, in a zebrafish embryonic angiogenesis assay, and in an alginate-encapsulate tumor cell assay. In vivo, oral administration of SKLB1206 showed complete tumor regression in gefitinib-sensitive HCC827 and PC-9 xenograft models and showed a considerable antitumor effect on the gefitinib-resistant H1975 model as well as other EGFR/ErbB2-overexpressing or -dependent tumor models including A431, LoVo, and N87 established in athymic mice. SKLB1206 also showed a very good oral bioavailability (50.1%). Collectively, these preclinical evaluations may support clinical development of SKLB1206 for cancers with EGFR-activating/resistance mutations or EGFR/ErbB2 overexpressed. Mol Cancer Ther; 11(4); 952–62. ©2012 AACR.

Table S1: Enzymatic activities of SKLB646 against recombinant human protein kinases, Related to Figure 1. Table S2: Inhibitory activities of SKLB646 or dasatinib against various TNBC cell lines together with characterizations of these cell lines, Related to Figure 1. Table S3: Inhibitory activities of SKLB646 against selected cancer cell lines and non-cancer cell lines, Related to Figure 1. Table S4: Pharmacokinetic parameters of SKLB646 in Sprague-Dawley rats, Related to Figure 6. Figure S1: A synthetic route for the target compound SKLB646, Related to Figure 1. Figure S2: The growth inhibition profile of HUVEC after treatment with different doses of SKLB646 or dasatinib for 72 hours, Related to Figure 4. Figure S3: Effects of SKLB646 treatment on weight of mice in human TNBC tumor xenografts models, Related to Figure 5. Figure S4: Quantitative analyses of the percentage of positive cells of Ki67 and C-CASP3 on tumor tissues of mice in human TNBC tumor xenograft models, Related to Figure 5. Figure S5: The proapoptosis effect of SKLB646 on tumor tissues of mice in human TNBC tumor xenograft models, Related to Figure 5. Supplementary Methods Supplementary Figure legends

Cancers resist targeted therapeutics by drug-escape signaling. Multitarget drugs co-targeting cancer and drug-escape mediators (DEMs) are clinically advantageous. DEM coverage may be expanded by drug combinations. This work evaluated to what extent the kinase DEMs (KDEMs) can be optimally co-targeted by drug combinations based on target promiscuities of individual drugs. We focused on 41 approved and 28 clinical trial small molecule kinase inhibitor drugs with available experimental kinome and clinical pharmacokinetic data. From the kinome inhibitory profiles of these drugs, drug combinations were assembled for optimally co-targeting an established cancer target (EGFR, HER2, ABL1, or MEK1) and 9-16 target-associated KDEMs at comparable potency levels as that against the cancer target. Each set of two-, three-, and four-drug combinations co-target 36-71%, 44-89%, 50-88%, and 27-55% KDEMs of EGFR, HER2, ABL1, and MEK1, respectively, compared with the 36, 33, 38, and 18% KDEMs maximally co-targeted by an existing drug or drug combination approved or clinically tested for the respective cancer. Some co-targeted KDEMs are not covered by any existing drug or drug combination. Our work suggested that novel drug combinations may be constructed for optimally co-targeting cancer and drug escape by the exploitation of drug target promiscuities.

Aberrant expression of protein arginine methyltransferases (PRMTs) has been implicated in a number of cancers, making PRMTs potential therapeutic targets. But it remains not well understood how PRMTs impact specific oncogenic pathways. We previously identified PRMTs as important regulators of cell growth in neuroblastoma, a deadly childhood tumor of the sympathetic nervous system. Here, we demonstrate a critical role for PRMT1 in neuroblastoma cell survival. PRMT1 depletion decreased the ability of murine neuroblastoma sphere cells to grow and form spheres, and suppressed proliferation and induced apoptosis of human neuroblastoma cells. Mechanistic studies reveal the prosurvival factor, activating transcription factor 5 (ATF5) as a downstream effector of PRMT1-mediated survival signaling. Furthermore, a diamidine class of PRMT1 inhibitors exhibited anti-neuroblastoma efficacy both in vitro and in vivo. Importantly, overexpression of ATF5 rescued cell apoptosis triggered by PRMT1 inhibition genetically or pharmacologically. Taken together, our findings shed new insights into PRMT1 signaling pathway, and provide evidence for PRMT1 as an actionable therapeutic target in neuroblastoma.

A-to-I RNA editing and m6A modification are two of the most prevalent types of RNA modifications controlling gene expression in mammals and play very important roles in tumorigenesis and tumor progression. However, the functional roles and correlations of these two RNA modifications remain to be further investigated in cancer. Herein, we show that ADAR1, an A-to-I RNA-editing enzyme, interacts with METTL3 and increases its protein level to promote the proliferation, migration and invasion of breast cancer cells through a mechanism connecting ADAR1, METTL3 and YTHDF1. We show that both ADAR1 and METTL3 are upregulated in breast cancer samples, and ADAR1 positively correlates with METTL3; ADAR1 edits METTL3 mRNA and changes its binding site to miR532-5p, leading to increased METTL3 protein, which further targets ARHGAP5, recognized by YTHDF1. Additionally, we show that loss of ADAR1 significantly inhibits breast cancer growth in vivo. Collectively, our findings identify the ADAR1–METTL3 axis as a novel, important pathway that connects A-to-I editing and m6A RNA modifications during breast cancer progression.

8-Chloro-adenosine (8-Cl-Ado) has been shown to exhibit its antitumor activity by inducing apoptosis in human lung cancer A549 and H1299 cells or autophagy in chronic lymphocytic leukemia, and MDA-MB-231 and MCF-7 breast cancer cells. Adenosine deaminases acting on RNA 1 (ADAR1) is tightly associated with cancer development and progression. The aim of this study was to investigate the role of ADAR1 in the proliferation of MDA-MB-231 and SK-BR-3 breast cancer cell lines after 8-Cl-Ado exposure and its possible mechanisms. After 8-Cl-Ado exposure, CCK-8 assay was performed to determine the cell proliferation; flow cytometry was used to analyze the cell cycle profiles and apoptosis; and the protein levels of ADAR1, p53, p21, and cyclin D1 were measured by western blotting. The results showed that the cell proliferation was greatly inhibited, G1 cell cycle was arrested, and apoptosis was induced after 8-Cl-Ado exposure. ADAR1 and cyclin D1 protein levels were dramatically decreased, while p53 and p21 levels were increased after 8-Cl-Ado exposure. Moreover, the cell growth inhibition was rescued, apoptosis was reduced, and p53 and p21 protein levels were downregulated, while cyclin D1 was upregulated when cells were transfected with plasmids expressing ADAR1 proteins. More importantly, RNA-binding domain of ADAR1 is critical to the cell growth inhibition of breast cancer cells exposed to 8-Cl-Ado. Together, 8-Cl-Ado inhibits the cell proliferation, induces G1 phase arrest and apoptosis at least by targeting ADAR1/p53/p21 signaling pathway. The findings may provide us with insights into the role of ADAR1 in breast cancer progression and help us better understand the effects of 8-Cl-Ado in the treatment of breast cancer.

Colorectal carcinoma (CRC) is the one of the most common cancers with considerable metastatic potential, explaining the need for new drug candidates that inhibit tumor metastasis. The signal transducers and activators of the transcription 3 (Stat3) signaling pathway has an important role in CRC and has been validated as a promising anticancer target for CRC therapy. In the present study, we report our findings on nifuroxazide, an antidiarrheal agent identified as an inhibitor of Stat3. Our studies showed that nifuroxazide decreased the viability of three CRC cell lines and induced apoptosis of cancer cells in a concentration-dependent manner. Moreover, western blot analysis demonstrated that the occurrence of its apoptosis was correlated with the activation of Bax and cleaved caspase-3, and decreased the expression of Bcl-2. In addition, nifuroxazide markedly impaired CRC cell migration and invasion by downregulating phosphorylated-Stat3

The clinical advantage of co-targeting cancer drug escape has been indicated by the percentage of these co-targeting drugs among all multi-target drugs in clinics and clinical trials. This clinical advantage needs to be further interrogated from such perspectives as the clinical impact of multi-target inhibition of drug-escape mediators. This impact may be reflected by drug sales data, that is, multi-target inhibition of higher number of drug-escape mediators favors the expanded coverage of drug-resistant patients leading to higher sales. We investigated whether this expectation is followed by the 25 FDA-approved anticancer kinase inhibitors, which were divided into 11 groups of comparable therapeutic mechanisms and approval years. We found 19 (76%) drugs to follow and 3 (12%) drugs not to follow this expectation. The remaining two (8%) and one (4%) drugs cannot be assessed due to insufficient data and incomparability. Therefore, drug sales strongly indicate the clinical advantage of multi-target inhibition of cancer drug escapes.

Human lung cancer H1299 (p53-null) cells often display enhanced susceptibility to chemotherapeutics comparing to A549 (p53-wt) cells. However, little is known regarding to the association of DNA damage-response (DDR) pathway heterogeneity with drug sensitivity in these two cells. We investigated the DDR pathway differences between A549 and H1299 cells exposed to 8-chloro-adenosine (8-Cl-Ado), a potential anticancer drug that can induce DNA double-strand breaks (DSBs), and found that the hypersensitivity of H1299 cells to 8-Cl-Ado is associated with its DSB overaccumulation. The major causes of excessive DSBs in H1299 cells are as follows: First, defect of p53-p21 signal and phosphorylation of SMC1 increase S phase cells, where replication of DNA containing single-strand DNA break (SSB) produces more DSBs in H1299 cells. Second, p53 defect and no available induction of DNA repair protein p53R2 impair DNA repair activity in H1299 cells more severely than A549 cells. Third, cleavage of PARP-1 inhibits topoisomerase I and/or topoisomerase I-like activity of PARP-1, aggravates DNA DSBs and DNA repair mechanism impairment in H1299 cells. Together, DDR pathway heterogeneity of cancer cells is linked to cancer susceptibility to DNA damage-based chemotherapeutics, which may provide aid in design of chemotherapy strategy to improve treatment outcomes.

The selection of the right drug targets is critically important for the successful and cost-effective development and clinical testing of drugs. A 2009 paper reported an in silico prospective prediction of the clinical potential of 156 targets of clinical trial drugs (all of these targets were without an approved drug at the time of the paper's publication). Eight years later, the assessment of the clinical status of these targets revealed impressive capability of the in silico method in prospectively predicting the clinical success of drug targets.

Lipase-catalyzed direct vinylogous Michael addition reactions of electron-deficient vinyl malononitriles to nitroalkenes are reported for the first time. A series of nitroalkenes reacting with vinyl malononitriles generate the corresponding products with moderate to high yields in the presence of Lipozyme® (immobilized lipase from Mucor miehei) with excellent diastereoselectivities in all reactions under optimized conditions. Docking studies were performed to further elucidate the differences between the various enzymes and substrates. Furthermore, we demonstrated the synthetic potential of the multi-functional products by performing reactions that employed the electron-deficient alkylidene double bond.

A fast large-scale synthesis of fluorescent carbon dots (CDs) has been developed in this work without high temperature or high pressure. Using benzenediols (catechol, resorcinol and hydroquinone) as the carbon precursor and sulfuric acid as the catalyst, three distinct CDs with strong and stable luminescence were prepared via a microwave-assisted method within 2 min. Characterizations through high-resolution transmission electron microscopy, X-ray diffraction, elemental analysis and infrared spectroscopy indicated the as-prepared CDs are dispersed spherical oxygenous carbon nanoparticles with 0.5–6 nm sizes. The structure differences caused by the isomer precursors were reflected in the chemical and fluorescent properties of CDs. The quantum yields of the three kinds of CDs derived from catechol, resorcinol and hydroquinone are 9.2%, 42.8% and 26.5%, respectively, and the fluorescence lifetimes of these CDs are on the nanosecond scale. The CDs derived from hydroquinone could easily penetrate into cells in a short time (30 min) and possess low cytotoxicity and good biocompatibility which may have great potential for bioimaging applications.

New CYP 119 T213G mutants were constructed and characterized. Introduction of the T213G mutation into the wild-type CYP 119 significantly enhances the turnover rate for the peroxide-dependent styrene epoxidation 4.4-fold to 346.2 min−1, and the double T213G/T214V mutant improves the ratio of the S- and R-enantiomers of the epoxide products 2- fold to 5.8. The molecular modelling and docking results support our initial design and experimental data.

Prediction of polypharmacology of known drugs and new molecules against selected multiple targets is highly useful for finding new therapeutic applications of existing drugs (drug repositioning) and for discovering multi-target drugs with improved therapeutic efficacies by collective regulations of primary therapeutic targets, compensatory signalling and drug resistance mechanisms. In this review, we describe recent progresses in exploration of in-silico methods for predicting polypharmacology of known drugs and new molecules by means of structure-based (molecular docking, binding- site structural similarity, receptor-based pharmacophore searching), expression-based (expression profile/signature similarity disease-drug and drug-drug networks), ligand-based (similarity searching, side-effect similarity, QSAR, machine learning), and fragment-based approaches that have shown promising potential in facilitating drug repositioning and the discovery of multi-target drugs.