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VEGFR-2 is an attractive target for the development of anti-tumor drugs and plays a crucial role in tumor angiogenesis. This study reports a series of novel thiophene-3-carboxamide derivatives based on PAN-90806 as VEGFR-2 inhibitors, among which compound 14d exhibits excellent anti-proliferative activity against HCT116, MCF7, PC3, and A549 cell lines, and has effective VEGFR-2 inhibitory activity with an IC 50 value of 191.1 nM. Additionally, CETSA results indicated that VEGFR-2 was a relevant target of compound 14d in the cell lines, and compound 14d could also inhibit VEGFR-2 protein phosphorylation in A549 cell line. Furthermore, compound 14d inhibited colony formation, cell migration, and HUVECs tube formation in a dose-dependent manner. The mechanism by which 14d induced cancer cell death involves blocking the cell cycle, increasing ROS production, inducing apoptosis, and dose-dependently reducing the levels of phosphorylated ERK and MEK. Molecular docking and molecular dynamics simulations had shown that compound 14d could stably bind to the active site of VEGFR-2. These results confirmed that compound 14d might be a promising lead compound for anti-angiogenesis., 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 © 2024 Elsevier Inc. All rights reserved.)

In this study, 2-benzyl-10a-(1 H -pyrrol-2-yl)-2,3-dihydropyrazino[1,2- a ]indole-1,4,10(10a H )-trione (DHPITO), a previously identified inhibitor against hepatocellular carcinoma cells, is shown to exert its cytotoxic effects by suppressing the proliferation and growth of CRC cells. An investigation of its molecular mechanism confirmed that the cytotoxic activity of DHPITO is mediated through the targeting of microtubules with the promotion of subsequent microtubule polymerisation. With its microtubule-stabilising ability, DHPITO also consistently arrested the cell cycle of the CRC cells at the G2/M phase by promoting the phosphorylation of histone 3 and the accumulation of EB1 at the cell equator, reduced the levels of CRC cell migration and invasion, and induced cellular apoptosis. Furthermore, the compound could suppress both tumour size and tumour weight in a CRC xenograft model without any obvious side effects. Taken together, the findings of the present study reveal the antiproliferative and antitumour mechanisms through which DHPITO exerts its activity, indicating its potential as a putative chemotherapeutic agent and lead compound with a novel structure.

The constitutive activation of ERK1/2 (RAF-MEK-ERK) signaling pathway has been widely observed in many types of tumors, and the blockade of ERK1/2 signaling pathway has been proved to reduce tumor growth. Therefore, ERK1/2 signaling pathway has become an interesting therapeutic target for cancer therapy. Despite the successful development of BRAF and MEK inhibitors in clinic treatment, resistance often appears to re-enhance ERK1/2 signaling. Here we report the design, synthesis, biological activity of a series of novel pyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione derivatives based on compound 1. Among them, the target compound N-(3-chlorophenyl)-2-((1,3-dimethyl-7-(4-methylpiperazin-1-yl)-2,4-dioxo-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidin-5-yl)amino)acetamide (14m) exhibited excellent antiproliferative activity towards MCF-7, A375, SK-MEL-2 and SK-HEP-1 cells, with low cytotoxicity in C28/I2 cells. Tumor spheroid assay demonstrated the superior potency of 14m in inhibiting the growth of SK-HEP-1 spheroidal models. The mechanism of 14m to induce cancer cell death was shown to suppress cell migrations, induce cell apoptosis, decrease the levels of phosphorylated ERK and MEK in a dose-dependent manner and increase ROS production., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

The development of cancer treatments requires continuous exploration and improvement, in which the discovery of new drugs for the treatment of cancer is still an important pathway. In this study, based on the molecular hybridization strategy, a new structural framework with an N -aryl- N '-arylmethylurea scaffold was designed, and 16 new target compounds were synthesized and evaluated for their antiproliferative activities against four different cancer cell lines A549, MCF7, HCT116, PC3, and human liver normal cell line HL7702. The results have shown seven compounds with 1-methylpiperidin-4-yl groups having excellent activities against all four cancer cell lines, and they exhibited scarcely any activities against HL7702. Among them, compound 9b and 9d showed greatly excellent activity against the four kinds of cells, and the IC 50 for MCF7 and PC3 cell lines were even less than 3 μM.

A docking study of a novel series of benzofuran derivatives with ERα was conducted. In this study, we report the synthesis of a novel series of benzofuran derivatives and evaluation of their anticancer activity in vitro against MCF-7 human breast cancer cells, as well as their potential toxicity to ER-independent MDA-MB-231 breast cancer cells, human renal epithelial HEK-293 cells, and human immortal keratinocytes (HaCaT cells) by using the MTT colorimetric assay. The screening results indicated that the target compounds exhibited anti-breast cancer activity. The target compound 2-benzoyl-3-methyl-6-[2-(morpholin-4-yl)ethoxy]benzofuran hydrochloride (4e) exhibited excellent activity against anti-oestrogen receptor-dependent breast cancer cells and low toxicity. The preliminary structure-activity relationships of the target benzofuran derivatives have been summarised. In conclusion, the novel benzofuran scaffold may be a promising lead for the development of potential oestrogen receptor inhibitors., Competing Interests: Declaration of Competing Interest All authors declare that there are no conflicts of interest associated with the publication of this manuscript., (Copyright © 2020 Elsevier Inc. All rights reserved.)

To discover new antiproliferative agents with high efficacy and selectivity, a new series of 1-aryl-3-{4-[(pyridin-2-ylmethyl)thio]phenyl}urea derivatives ( 7a - 7t ) were designed, synthesized and evaluated for their antiproliferative activity against A549, HCT-116 and PC-3 cancer cell lines in vitro. Most of the target compounds demonstrated significant antiproliferative effects on all the selective cancer cell lines. Among them, the target compound, 1-[4-chloro-3-(trifluoromethyl)phenyl]-3-{4-{{[3-methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methyl}thio}phenyl}urea ( 7i ) was identified to be the most active one against three cell lines, which was more potent than the positive control with an IC 50 value of 1.53 ± 0.46, 1.11 ± 0.34 and 1.98 ± 1.27 μM, respectively. Further cellular mechanism studies confirmed that compound 7i could induce the apoptosis of A549 cells in a concentration-dependent manner and elucidated compound 7i arrests cell cycle at G1 phase by flow cytometry analysis. Herein, the studies suggested that the 1-aryl-3-{4-[(pyridin-2-ylmethyl)thio]phenyl}urea skeleton might be regarded as new chemotypes for designing effective antiproliferative agents.

Based on the analysis of epidermal growth factor receptor (EGFR) complexes with gefitinib with molecular docking, the scaffold-hopping strategy, combination of the active substructures, and structural optimization of EGFR inhibitors, a novel series of benzo[4,5]imidazo[2,1- b ]thiazole derivatives was designed, synthesized, and evaluated for antitumor activity in human cancer cell lines and cellular toxicity against human normal cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay and EGFR inhibitory activities in vitro. Some target compounds such as 2-(benzo[4,5]imidazo[2,1- b ]thiazol-3-yl)-N-(2-hydroxyphenyl)acetamide ( D04 ) and 2-(benzo[4,5]imidazo[2,1- b ]thiazol-3-yl)-N-(naphthalen-1-yl)acetamide ( D08 ) have shown significant antitumor activity against the EGFR high-expressed human cell line HeLa. All the target compounds showed hardly any antitumor activity against the EGFR low-expressed human cell line HepG2, and nearly no cellular toxicity against the human normal cell lines HL7702 and human umbilical vein endothelial cell lines (HUVEC). The inhibitory activities against EGFR kinase in vitro of the three target compounds were greatly consistent with the anti-proliferative activities. The preliminary structure⁻activity relationships of the target compounds were summarized. Conclusively, the novel benzo[4,5]imidazo[2,1- b ]thiazole derivatives as novel potential EGFR inhibitors may be used as the potential lead compounds for the development of antitumor agents.

A fluorescent 2,7-dimethoxy-substituted calix[4]carbazole (1) is facilely synthesized. The spectral behaviors of both the guest-induced switchable conformation of 1 and its abilities serving as the stabilizer and molecular carrier of curcumin are investigated. UV-vis, fluorescence and NMR spectral results show that upon binding to curcumin, the 1,3-alternate conformation of 1 is converted to be the cone one. The relative high association constant (6.4×10 6 M -1 ) of 1 binding to curcumin enables it to stabilize the curcumin, to suppress its degradation, and to sustainably deliver it into the EYPC vesicles within 20h. Moreover, the cytotoxicity assay shows that 1 does not interfere the antiproliferative activities of curcumin. All these properties endow 1 the potential capability of serving as the molecular drug carrier. Our current result may pave the way looking for more efficient fluorescent calixcarbazoles and thereof spectral utilities., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A sulfated 1,4-β-d-galactoglucan (B86-III) with 1,6-branches was isolated and identified from Antrodia cinnamomea. The repeating unit of B86-III was proposed based on one-dimensional 1D ( 1 H, 13 C and DEPT-135) and 2D (DQF-COSY, TOCSY, HSQC and HMBC) NMR spectra. The conformation of the sugars was hypothesized to be a rare boat form instead of a 4 C 1 chair form. The sulfate substitutions were suggested to be on the C-2 and C-3 positions, resulting in the following structure: B86-III inhibited the viability of H1975 lung cancer cells via cell apoptosis, including the activation of caspase 3 and PARP. Transforming growth factor β receptor (TGFR) and its downstream signaling FAK and Slug are involved in lung tumorigenesis. B86-III downregulated TGFR I protein levels and inhibited FAK phosphorylation, resulting in inhibition of Slug expression and migration. This study is the first to characterize sulfated polysaccharides with a rare boat-form conformation and identify the mechanism of inhibition lung cancer cell., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A sulfated polysaccharide of edible mushroom Antrodia cinnamomea (SPS) has been identified as a novel immunomodulatory agent. We examined the anti-cancer effects of SPS by conducting a series of in vitro studies. We found that SPS inhibits the growth of A549 and LLC1 lung cancer cells via the induction of cell cycle arrest and activation of caspase 3 and PARP. By contrast, we found that a non-sulfated polysaccharide of A. cinnamomea (NSPS) does not inhibit lung cancer cell viability. Moreover, NSPS does not induce changes in cell cycle distribution or activate apoptosis-related molecules in both A549 and LLC1 cells. High expression of transforming growth factor β (TGFβ) and TGFβ receptors (TGFRs) is correlated with lung tumorigenesis. SPS suppresses TGFβ-induced intracellular signaling events, including phosphorylation of Smad2/3, FAK, Akt, and cell migration. By contrast, non-sulfated polysaccharide (NSPS) does not exhibit the similar biological functions in both A549 and LLC1 cells. Mechanistically, we demonstrated SPS effectively reduces TGFR protein levels via induction of proteasome-dependent degradation pathway. Our study is the first to identify the pivotal role of SPS in the induction of TGFR degradation and activation of Caspase 3 and PARP, which leads to suppress viability and migration of lung cancer cells., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A series of novel hybrid compounds between benzofuran and N-aryl piperazine have been designed and prepared. These derivatives were evaluated for their in vitro anti-tumor activity against a panel of human tumor cell lines by MTT assay. The results demonstrated that amide derivatives were more bioactive than sulfonamide compounds in general, and that chloro or trifluoromethyl substituent was vital for modulating cytotoxic activity. In particular, compound 13 was found to be the most potent compound against 4 strains human tumor cell lines, and exhibited cytotoxic activity selectively against Hela (0.03μM)., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Our previous study demonstrated that promoter methylation of human mutL homolog 1 (hMLH1) is involved in determining sensitivity to cisplatin in NSCLC A549/DDP cell line, The present study was designed to determine whether DNA methylation of hMLH1 affects the prognosis of non-small cell lung cancer patients who received cisplatin-based adjuvant chemotherapy. Methylation status of hMLH1 was examined by nested methylation-specific PCR (nested MSP) in 84 archived NSCLC surgically resected tissue specimens from patients receiving cisplatin-based adjuvant chemotherapy. Univariate and multivariate analysis were used to investigate the relationship between hMLH1 methylation status and the clinical prognosis of the patients mentioned above. In the cohort of 84 NSCLC cases, 80 tissue samples were successfully amplified by nested MSP. Among them, 36 samples (45%) were identified to be methylated. Moreover, hMLH1 methylation was not associated with age, gender, smoking status, T stage, histology and differentiation, but correlated with lymphatic metastasis (P=0.021). Multivariate logistic regression analysis showed that hMLH1 methylation may function as a significant independent prognostic factor for tumor recurrence in NSCLC patients treated with adjuvant cisplatin (HR 3.114, 95% CI 1.032-9.399; P=0.044). However, Kaplan-Meier method (P=0.093) and multivariate Cox regression analysis (P=0.598) revealed that hMLH1 methylation was not associated with the survival of these patients. To conclude, the cisplatin-based adjuvant chemotherapy is more beneficial for NSCLC patients without hMLH1 methylation. hMLH1 methylation may have a potential to become a biomarker of individualized therapy for NSCLC patients.

RAD51 recombinase plays a critical role for cancer cell proliferation and survival. Targeting RAD51 is therefore an attractive strategy for treating difficult-to-treat cancers, e.g. triple negative breast cancers which are often resistant to existing therapeutics. To this end, we have designed, synthesized and evaluated a panel of new RAD51 inhibitors, denoted IBR compounds. Among these compounds, we have identified a novel small molecule RAD51 inhibitor, IBR120, which exhibited a 4.8-fold improved growth inhibition activity in triple negative human breast cancer cell line MBA-MD-468. IBR120 also inhibited the proliferation of a broad spectrum of other cancer cell types. Approximately 10-fold difference between the IC50 values in normal and cancer cells were observed. Moreover, IBR120 was capable of disrupting RAD51 multimerization, impairing homologous recombination repair, and inducing apoptotic cell death. Therefore, these novel RAD51 inhibitors may serve as potential candidates for the development of pharmaceutical strategies against difficult-to-treat cancers., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Treatment of recurrent and metastatic cervical cancer remains a challenge, especially in developing countries, which lack efficient screening programs. In recent years, artemisinin and its derivatives, such as dihydroartemisinin (DHA), which were traditionally used as anti-malarial agent, have been shown to inhibit tumor growth with low toxicity to normal cells. In this study, we investigated mechanisms underlying the anti-tumor effect of DHA in cervical cancer. We evaluated the role of DHA on the expression of bcl-2 and Raf kinase inhibitor protein (RKIP), which is a suppressor of metastasis. The MTT assay was used to compare the proliferation of untreated and DHA-treated Hela and Caski cervical cancer cells. Flow cytometry was used to determine the percentage of cells at each stage of the cell cycle in untreated and DHA-treated cells. We used RT-PCR and western blots to determine the expression of bcl-2 and RKIP mRNA and proteins. We evaluated the effect of DHA treatment in nude mice bearing Hela or Caski tumors. DHA-treated cells showed a time- and dose-dependent inhibition of proliferation and a significant increase in apoptosis. The expression of RKIP was significantly upregulated and the expression of bcl-2 was significantly downregulated in DHA-treated cells compared with control cells. DHA treatment caused (1) a significant inhibition of tumor growth and (2) a significant increase in the apoptotic index in nude mice bearing Hela or Caski tumors. Our data suggest that DHA inhibits cervical cancer growth via upregulation of RKIP and downregulation of bcl-2.

Estrogen receptors (ERs) are members of a superfamily of ligand-modulated nuclear receptors, which have been associated with an increased risk of cardiovascular diseases and breast cancer. Based on molecular docking studies, 1,4-dihydrothieno[3',2':5,6]thiopyrano[4,3-c]pyrazole-3-carboxamide derivatives as estrogen receptor inhibitors with a new scaffold , have been synthesized and tested for the antitumor activity on the ER expressing (ER dependent) human MCF-7 breast cancer cell line. According to the biological activity evaluation, compound 6a demonstrated the most potent antiproliferative activity (relative inhibitory rate: 100%). Several of these compounds exhibited moderate antitumor activity and worthy of further modification to obtain more potent anticancer candidate drugs.

RAD51 recombinase activity plays a critical role for cancer cell proliferation and survival, and often contributes to drug-resistance. Abnormally elevated RAD51 function and hyperactive homologous recombination (HR) rates have been found in a panel of cancers, including breast cancer and chronic myeloid leukaemia (CML). Directly targeting RAD51 and attenuating the deregulated RAD51 activity has therefore been proposed as an alternative and supplementary strategy for cancer treatment. Here we show that a newly identified small molecule, IBR2, disrupts RAD51 multimerization, accelerates proteasome-mediated RAD51 protein degradation, reduces ionizing radiation-induced RAD51 foci formation, impairs HR, inhibits cancer cell growth and induces apoptosis. In a murine imatinib-resistant CML model bearing the T315I Bcr-abl mutation, IBR2, but not imatinib, significantly prolonged animal survival. Moreover, IBR2 effectively inhibits the proliferation of CD34(+) progenitor cells from CML patients resistant to known BCR-ABL inhibitors. Therefore, small molecule inhibitors of RAD51 may suggest a novel class of broad-spectrum therapeutics for difficult-to-treat cancers., (Copyright © 2013 The Authors. Published by John Wiley and Sons, Ltd on behalf of EMBO.)

The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay is a widely accepted cytotoxicity assay which can produce inaccurate results due to possible interference with the antioxidant property of anthocyanins. Alternative methods to the MTT assay, such as BrdU (DNA-based) and CellTiter-Glo (ATP-based) assays were evaluated to assess anthocyanin cytotoxicity, derived from blackberry in LNCaP, MCF-7 and MDA-MB-453 cell lines. The standard cell counting method was the reference assay. Greater correlation of cell viability values following anthocyanin exposure was obtained from multiple cell lines with the alternative assays when compared with cell counting. MTT and cell counting results were not always correlated, albeit this was a function of cell type. In particular, poor correlations between cell counting and MTT procedures used to assess cytotoxicity of anthocyanins were observed in the MDA-MB-453 cell lines. Comparison of cytotoxicity derived from alternative assays and the MTT assays with the cell counting method was dependent on the assay procedure and the cell type. The LC(50) of blackberry crude extract ranged from 0.4 to 9.4 mg/mL between assays and across all cell lines, whereas a semi-purified anthocyanin extract was not cytotoxic. Cytotoxicity evaluation of polyphenolic-rich extracts using BrdU and CellTiter-Glo assays as alternatives to the MTT method is recommended.

This study was conducted to investigate the chemical antioxidant and bioactive properties of the water (WF) and ethyl acetate fractions (EAF) derived from dandelion (Taraxacum officinale) flower extract (DFE). HPLC analysis showed the presence of both luteolin and luteolin 7-glucoside in the DFE, which contributed to noted in vitro antioxidant and Caco-2 cell cytotoxic activities. Both WF and EAF of DFE exhibited free radical scavenging activities in a stable 2,2-diphenyl-1-picrylhydrazyl radical model and reduced the breakage of supercoiled DNA strand induced by both non-site-specific and site-specific hydroxyl radical. Oxidation of structured phosphatidylcholine liposome induced by peroxyl radical was reduced in the presence of both EAF and WF. EAF had greater (p < 0.05) affinity to scavenge peroxyl radical than WF, as measured by the formation of conjugated diene. At low concentration, prooxidant activity of both fractions was observed in Cu(2+)-induced structured liposome and hLDL oxidation models, thus indicating that the reducing power of the DFE had resulted in generation of reactive cuprous ion. However, at high concentrations the EAF did not promote oxidation in the presence of Cu(2+), suggesting that the free radical scavenging activity of this fraction was sufficient to minimize the potential oxidative mechanism attributed to the metal ion reducing activity associated with prooxidant activity.

RAD51 recombinase plays a critical role for cancer cell proliferation and survival. Targeting RAD51 is therefore an attractive strategy for treating difficult-to-treat cancers, e.g. triple negative breast cancers which are often resistant to existing therapeutics. To this end, we have designed, synthesized and evaluated a panel of new RAD51 inhibitors, denoted IBR compounds. Among these compounds, we have identified a novel small molecule RAD51 inhibitor, IBR120, which exhibited a 4.8-fold improved growth inhibition activity in triple negative human breast cancer cell line MBA-MD-468. IBR120 also inhibited the proliferation of a broad spectrum of other cancer cell types. Approximately 10-fold difference between the IC50 values in normal and cancer cells were observed. Moreover, IBR120 was capable of disrupting RAD51 multimerization, impairing homologous recombination repair, and inducing apoptotic cell death. Therefore, these novel RAD51 inhibitors may serve as potential candidates for the development of pharmaceutical strategies against difficult-to-treat cancers.

Fish bone fermented using Monascus purpureus (FBF) has total phenols and functional amino acids that contribute to its anti-oxidant and anti-inflammatory properties. Colorectal cancer, one of the most prevalent cancers and the third largest cause of death worldwide, has become a serious threat to global health. This study investigates the anti-cancer effects of FBF (1, 2.5 or 5 mg/mL) on the cell growth and molecular mechanism of HCT-116 cells. The HCT-116 cell treatment with 2.5 or 5 mg/mL of FBF for 24 h significantly decreased cell viability (p < 0.05). The S and G2/M phases significantly increased by 88–105% and 25–43%, respectively (p < 0.05). Additionally, FBF increased the mRNA expression of caspase 8 (38–77%), protein expression of caspase 3 (34–94%), poly (ADP-ribose) polymerase (PARP) (31–34%) and induced apoptosis (236–773%) of HCT-116 cells (p < 0.05). FBF also increased microtubule-associated protein 1B light chain 3 (LC3) (38–48%) and phosphoinositide 3 kinase class III (PI3K III) (32–53%) protein expression, thereby inducing autophagy (26–52%) of HCT-116 cells (p < 0.05). These results showed that FBF could inhibit HCT-116 cell growth by inducing S and G2/M phase arrest of the cell cycle, apoptosis and autophagy. Thus, FBF has the potential to treat colorectal cancer. [ABSTRACT FROM AUTHOR]

Elevating cancer cell intracellular ROS production has been proven to be effective for cancer therapies. In this work, a series of 1,3-diphenylpyrimidine-2,4(1H,3H)-dione derivatives were designed and synthesized, of which the target compound XS23, N-(2,6-dioxo-1,3-di-m-tolyl-1,2,3,6-tetrahydropyrimidin-4-yl)-N-(3-morpholinopropyl)-2-phenylacetamide, exhibited excellent antitumor cell proliferative activity against multiple tumor cell lines. In the study of the antitumor mechanism of XS23, we confirmed that it can inhibit tumor cell migration and proliferation in a concentration-dependent manner in A375 cells. Besides, 5 μM of XS23 could induce 18% early cell apoptosis and 4.68% late cell apoptosis in A375 cells. XS23 can also dose-dependently and time-dependently increase cleaved the caspase-9 protein expression in A375 cells and increase the intracellular ROS level of A375 cells up to 175-fold compared with the negative control after 12 h, implying that XS23 can induce cancer cell apoptosis by elevating ROS production. [ABSTRACT FROM AUTHOR]

Cervical cancer is one of the primary causes of cancer‑associated mortality worldwide. Due to the increasing incidence of cervical cancer, multiple treatment options are required. Initial responses to chemotherapy and surgical interventions are generally positive, however patients often experience relapse and tumor recurrence. Currently, the effects of cucurbitacins on different types of cancer are being investigated, as they exhibit a wide variety of bioactivities. The anticancer activity of the cucurbitacin 23,24‑dihydrocucurbitacin B against a panel of human cervical cancer cell lines was investigated in the current study. Cell viability was determined using an MTT assay and apoptosis was detected using DAPI staining. The proportion of apoptotic cells, cell cycle distribution, mitochondrial membrane potential (ΔΨm) and reactive oxygen species (ROS) levels were estimated using flow cytometry. Protein expression was determined using western blot analysis. The results of the current study indicated that 23,24‑dihydrocucurbitacin B inhibited the viability of human cervical cancer cell lines and had an IC50 of 40‑60 µM. However, its cytotoxic effects were much less pronounced in normal epithelial fr2 and HerEpiC cells, where it had an IC50 of 125 µM. The underlying mechanisms of this were further studied and the results demonstrated that 23,24‑dihydrocucurbitacin B induced apoptosis in HeLa cells and caused ROS‑mediated shifts in the ΔΨm. Additionally, it caused the cell cycle arrest of HeLa cells at the G2/M checkpoint. The phosphoinositide 3 kinase/protein kinase B/mechanistic target of rampamycin (PI3K/AKT/mTOR) cascade may serve an important role in cancer tumorigenesis, progression and resistance to chemotherapy. The results indicated that 23,24‑dihydrocucurbitacin B significantly decreased the expression of important proteins in the PI3K/Akt/mTOR cascade. Taken together, these results suggest that 23,24‑dihydrocucurbitacin B may be novel method of treating cervical cancer. [ABSTRACT FROM AUTHOR]

An efficient partial synthesis of 25-acetoxy-3α-hydroxyolean-12-en-28-oic acid (1), starting from oleanolic acid (2), has been developed in an efficient manner (13 steps, 21% yield), employing a photochemical reaction of nitrite 8 for the introduction of C-25 substituting group as the key step. Based on the comparison of its spectral data with those reported for compound 1 isolated from Liquidamber styraciflua, we found the structure in that paper was incorrectly assigned, and should be revised as 3α-acetoxy-25-hydroxyolean-12-en-28-oic acid (15). [ABSTRACT FROM AUTHOR]

Abstract: Blocking human thymidylate kinase (TMPK) function has a chemosensitization effect in anticancer treatment. However, a rapid and sensitive TMPK activity assay method suitable for inhibitor screening has been lacking. We have designed a luciferase-coupled TMPK assay in which luminescence emission is proportional to the magnitude of TMPK inhibition. The advantages of using this new method over the conventional nicotinamide adenine dinucleotide (reduced form, NADH)-coupling method in screening inhibitor include low cost, low limit in detecting inhibitory signal, more accurate, and devoid of interference due to compound absorbance at 340nm. [Copyright &y& Elsevier]

Based on the analysis of epidermal growth factor receptor (EGFR) complexes with gefitinib with molecular docking, the scaffold-hopping strategy, combination of the active substructures, and structural optimization of EGFR inhibitors, a novel series of benzo[4,5]imidazo[2,1-b]thiazole derivatives was designed, synthesized, and evaluated for antitumor activity in human cancer cell lines and cellular toxicity against human normal cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay and EGFR inhibitory activities in vitro. Some target compounds such as 2-(benzo[4,5]imidazo[2,1-b]thiazol-3-yl)-N-(2-hydroxyphenyl)acetamide (D04) and 2-(benzo[4,5]imidazo[2,1-b]thiazol-3-yl)-N-(naphthalen-1-yl)acetamide (D08) have shown significant antitumor activity against the EGFR high-expressed human cell line HeLa. All the target compounds showed hardly any antitumor activity against the EGFR low-expressed human cell line HepG2, and nearly no cellular toxicity against the human normal cell lines HL7702 and human umbilical vein endothelial cell lines (HUVEC). The inhibitory activities against EGFR kinase in vitro of the three target compounds were greatly consistent with the anti-proliferative activities. The preliminary structure–activity relationships of the target compounds were summarized. Conclusively, the novel benzo[4,5]imidazo[2,1-b]thiazole derivatives as novel potential EGFR inhibitors may be used as the potential lead compounds for the development of antitumor agents. [ABSTRACT FROM AUTHOR]

Cisplatin is a highly effective anti-cancer chemotherapeutic agent; however, its clinical use is severely limited by serious side effects, of which nephrotoxicity is the most important. In this study, we investigated whether Qiong-Yu-Gao (QYG), a popular traditional Chinese medicinal formula described 840 years ago, exhibits protective effects against cisplatin-induced renal toxicity. Using a mouse model of cisplatin-induced renal dysfunction, we observed that pretreatment with QYG attenuated cisplatin-induced elevations in blood urea nitrogen and creatinine levels, ameliorated renal tubular lesions, reduced apoptosis, and accelerated tubular cell regeneration. Cisplatin-mediated elevations in tumor necrosis factor alpha (TNF-α) mRNA, interleukin-1 beta (IL-1β) mRNA, and cyclooxygenase-2 (COX-2) protein in the kidney were also significantly suppressed by QYG treatment. Furthermore, QYG reduced platinum accumulation in the kidney by decreasing the expression of copper transporter 1 and organic cation transporter 2. An in vivo study using implanted Lewis lung cancer cells revealed that concurrent administration of QYG and cisplatin did not alter the anti-tumor activity of cisplatin. Our findings suggest that the traditional Chinese medicinal formula QYG inhibits cisplatin toxicity by several mechanisms that act simultaneously, without compromising its therapeutic efficacy. Therefore, QYG may be useful in the clinic as a protective agent to prevent cisplatin-induced nephrotoxicity. [ABSTRACT FROM AUTHOR]

[Display omitted] Auristatins-glucuronide conjugates designed targeting the β-Glucuronidase in tumor microenvironment were synthesized and evaluated on stabilities, the release of auristatins and the antitumor activities in this study. Conjugates 20 and 21 showed remarkable stabilities in phosphate buffer and bovine serum solution, and excellent selectivity between the in vitro antiproliferative activities against β-glucuronidase pretreated and untreated cancer cells (IC 50 = 5.7 nM ∼ 9.7 nM, IC 50 (-Enz) > 1 μM). Furthermore, conjugate 20 showed potent antitumor efficacy in HCT-116 xenograft mouse model without inducing side effects. [ABSTRACT FROM AUTHOR]