The Anticancer Effect of a Novel Quinoline Derivative 91b1 through Downregulation of Lumican.

Quinoline derivatives have been reported to possess a wide range of pharmaceutical activities. Our group previously synthesized a series of quinoline compounds, in which compound 91b1 showed a significant anticancer effect. The purpose of this study was to evaluate the anticancer activity of compound 91b1 in vitro and in vivo, and screen out its regulated target. A series of cancer cell lines and nontumor cell lines were treated with compound 91b1 by MTS cytotoxicity assay and cell-cycle assay. In vivo anticancer activity was evaluated by a xenografted model on nude mice. Target prediction of 91b1 was assessed by microarray assay and confirmed by pancancer analysis. Relative expression of the target gene Lumican was measured by qRT-PCR. 91b1 significantly reduced tumor size in the nude mice xenograft model. Lumican was downregulated after 91b1 treatment. Lumican was proven to increase tumorigenesis in vivo, as well as cancer cell migration, invasion, and proliferation in vitro. The results of this study suggest that the anticancer activity of compound 91b1 probably works through downregulating the gene Lumican.

GAEC1 drives colon cancer progression.

Gene amplified in esophageal cancer 1 (GAEC1) expression and copy number changes are frequently associated with the pathogenesis of colorectal carcinomas. The current study aimed to identify the pathway and its transcriptional factors with which GAEC1 interacts within colorectal cancer, to gain a better understanding of the mechanics by which this gene exercises its effect on colorectal cancer. Two colonic adenocarcinoma cell lines (SW48 and SW480) and a nonneoplastic colon epithelial cell line (FHC) were transfected with GAEC1 to assess the oncogenic potential of GAEC1 overexpression. Multiple in vitro assays, including cell proliferation, wound healing, clonogenic, apoptosis, cell cycle, and extracellular flux, were performed. Western blot analysis was performed to identify potential gene-interaction partners of GAEC1 in vitro. Results showed that the overexpression of GAEC1 significantly increased cell proliferation, migration, and clonogenic potential ( P < 0.05) of colonic adenocarcinoma. Furthermore, GAEC1 portrayed its ability to influence mitochondrial respiration changes. The observations were in tandem with a significant increase in the expression of phosphorylated protein kinase B, forkhead box O3, and matrix metallopeptidase 9. Thus, GAEC1 has a role in regulating gene pathways, potentially in the Akt pathway. This could help in developing targeted therapies in the future.

The design, synthesis and evaluation of selenium-containing 4-anilinoquinazoline hybrids as anticancer agents and a study of their mechanism.

Inhibition of tubulin polymerization is one of the significant strategies in the treatment of cancer. Inspired by the excellent antitumor activity of EP128495 and the beneficial biological activities of selenium compounds, a series of new selenium-containing 4-anilinoquinazoline hybrids were synthesized and evaluated as tubulin polymerization inhibitors. An anti-proliferative activity assay showed that most of the compounds inhibited human sensitive cancer cells at low nanomolar concentrations. A mechanism study revealed that the optimal compound 5a disrupted microtubule dynamics, decreased the mitochondrial membrane potential and arrested HeLa cells in the G2/M phase, finally resulting in cellular apoptosis.

Overexpression of microRNA-1288 in oesophageal squamous cell carcinoma.

PURPOSE: This study aims to examine the expression profiles miR-1288 in oesophageal squamous cell carcinoma (ESCC). The cellular implications and target interactions of ESCC cells following miR-1288 overexpression was also examined. METHODS: In total, 120 oesophageal tissues (90 primary ESCCs and 30 non-neoplastic tissues) were recruited for miR-1288 expression analysis using qRT-PCR. An exogenous miR-1288 mimic and its inhibitor were used to explore the in-vitro effects of miR-1288 on ESCC cells by performing cell proliferation, colony formation, cell invasion and migration assays. Localisation and modulatory changes of various miR-1288 regulated proteins such as FOXO1, p53, TAB3, BCL2 and kRAS was examined using immunofluorescence and western blot. RESULTS: Overexpression of miR-1288 was more often noted in ESCC tissues when compared to non-neoplastic oesophageal tissues. High expression was often noted in high grade carcinomas and with metastases. Patients with high levels of miR-1288 expression showed a slightly better survival compared to patients with low miR-1288 levels. Furthermore, overexpression of miR-1288 showed increased cell proliferation and colony formation, improved cell migration and enhanced cell invasion properties in ESCC cells. In addition, miR-1288 overexpression in ESCC cells showed repression of cytoplasmic tumour suppressor FOXO1 protein expression. Inversely, inhibition of miR-1288 expression exhibited remarkable upregulation of FOXO1 protein, while expressions of other tested proteins remain unchanged. CONCLUSIONS: Up regulation of miR-1288 expression in ESCC tissues and miR-1288 induced oncogenic features of ESCC cells in-vitro indicates the oncogenic roles of miR-1288 in ESCCs. Overexpression of miR-1288 play a key role in the pathogenesis of ESCCs and its modulation may have potential therapeutic value in patients with ESCC.

Preparation of 8-hydroxyquinoline derivatives as potential antibiotics against Staphylococcus aureus.

This work describes the preparation of quinoline compounds as possible anti-bacterial agents. The synthesized quinoline derivatives show anti-bacterial activity towards Staphylococcus aureus. It is interesting to observe that the synthetic 5,7-dibromo-2-methylquinolin-8-ol (4) shows a similar minimum inhibitory concentration of 6.25µg/mL as compared to that of methicillin (3.125µg/mL) against Staphylococcus aureus.

The puzzling issue of 'vehicle-treated control' when using ethanol as drug carrier for MCF-7 cells.

Ethanol has been commonly used as a vehicle for drug discovery purpose in vitro. The human breast cancer MCF-7 estrogen dependent cell line is a common in vitro model used for hormonal therapy study. However, special precaution is suggested when ethanol is used in pharmacological tests as solvent in order to evaluate the biological activity of potential drugs especially concerning about the MCF-7. Ethanol was shown to stimulate the proliferation of this estrogen receptor positive cell line. Here, we have further demonstrated that the dose responsive stimulatory effect of ethanol on the MCF-7 cells after pre-incubating the breast carcinoma cells with phenol red-free medium and stripped fetal bovine serum. Our findings open a discussion for the evaluation of ethanol as solvent for drug discovery and screening when using MCF-7 cells as a testing model.

Downregulation of chemokine (C­C motif) ligand 5 induced by a novel 8­hydroxyquinoline derivative (91b1) suppresses tumor invasiveness in esophageal carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a particularly aggressive form of cancer with high mortality. In the present study, a novel 8­hydroxyquinoline derivative (91b1) was investigated for its anticancer activities in ESCC along with its associated mechanisms. The in vitro cytotoxic effect of 91b1 were evaluated across five ESCC cell lines using MTS assay, with cisplatin serving as a comparative standard. Changes in gene expression profile were identified by cDNA microarray and further validated by qualitative PCR and immunostaining. Additionally, protein levels of the most notably downregulated target in archival ESCC samples were also studied. 91b1 demonstrated comparable anticancer effect with cisplatin. Notably, chemokine ligand 5 (Ccl5) was identified as the most substantially downregulated gene, with its suppression at both mRNA and protein expression in ESCC cells, exhibiting a dose­dependent manner. The recombinant human protein of CCL5 enhanced the invasion of ESCC cells using the Transwell assay. The upregulation of CCL5 protein was also detected in 50% of ESCC cell lines. CCL5 was also overexpressed in 76.9% of ESCC specimens. The overall results indicated that 91b1 could effectively induce anticancer effect on ESCC cells through downregulating CCL5 expression with suppression of tumor invasion. Overall, these findings suggested that 91b1 effectively inhibited ESCC cell proliferation and tumor invasion by downregulating CCL5 expression, highlighting its potential as a therapeutic agent for ESCC treatment.

In vivo antitumour activity of amphiphilic silicon(IV) phthalocyanine with axially ligated rhodamine B.

We explore the possible cellular cytotoxic activity of an amphiphilic silicon(IV) phthalocyanine with axially ligated rhodamine B under ambient light experimental environment as well as its in vivo antitumour potential using Hep3B hepatoma cell model. After loading into the Hep3B hepatoma cells, induction of cellular cytotoxicity and cell cycle arrest were detected. Strong growth inhibition of tumour xenograft together with significant tumour necrosis and limited toxicological effects exerted on the nude mice could be identified.

Tumor suppressor dual-specificity phosphatase 6 (DUSP6) impairs cell invasion and epithelial-mesenchymal transition (EMT)-associated phenotype.

Suppressive effects of DUSP6 in tumorigenesis and EMT-associated properties were observed. Dual-specificity phosphatase (DUSP6) is a MAP kinase phosphatase (MKP) negatively regulating the activity of ERK, one of the major molecular switches in the MAPK signaling cascade propagating the signaling responses during malignancies. The impact of DUSP6 in EMT and its contribution to tumor dissemination has not yet been characterized. Due to differences in tumor microenvironments affecting cell signaling during cancer progression, DUSP6 may play varying roles in tumor development. We sought to examine the potential role of DUSP6-mediated tumorigenesis and EMT-associated properties in two aerodigestive tract cancers, namely, esophageal squamous cell carcinoma (ESCC) and nasopharyngeal carcinoma (NPC). Significant loss of DUSP6 was observed in 100% of 11 ESCC cell lines and 71% of seven NPC cell lines. DUSP6 expression was down-regulated in 40% of 30 ESCC tumor tissues and 75% of 20 NPC tumor tissues compared to their respective normal counterparts. Suppressive effects of DUSP6 in tumor formation and cancer cell mobility are seen in in vivo tumorigenicity assay and in vitro colony formation, three-dimensional Matrigel culture, cell migration and invasion chamber tests. Notably, overexpression of DUSP6 impairs EMT-associated properties. Furthermore, tissue microarray analysis reveals a clinical association of DUSP6 expression with better patient survival. Taken together, our study provides a novel insight into understanding the functional impact of DUSP6 in tumorigenesis and metastasis of ESCC and NPC.

Development of phyllanthin containing microcapsules and their improved biological activity towards skin cells and Staphylococcus aureus.

Chitosan based microcapsule which encapsulated with phyllanthin was developed by simple coacervation. The composition and surface morphology of phyllanthin containing microcapsules were analyzed by Fourier Transform Infrared spectroscopy and Scanning Electron Microscopy, respectively. The release of phyllanthin from the microcapsules was found to be more than 60% after 120 h. In vitro biological assays demonstrated that these phyllanthin containing microcapsules showed a stronger anti-oxidation potential on both human fibroblasts and keratinocytes as well as a better growth inhibitory activity towards Staphylococcus aureus.

Chimeric antigen receptor T cells applied to solid tumors.

Chimeric antigen receptor T cell (CAR-T) therapy is novel tumor immunotherapy that enables autologous T to express synthetic receptors to specifically recognize the surface tumor-associated antigens for exerting subsequent antitumor effects, and eliminating the resistance, metastases and recurrence of cancer. Although CAR T cells have exhibited success in eradicating hematologic malignancies, their applications to solid tumors has not yet been achieved due to obstacles such as the immune-suppressor tumor microenvironment and lack of tumor specific target antigens. In this review, we presented advancements in the development of CAR T cell therapy in solid tumors, and offered a brief summary of the challenges, as well as novel engineering and pharmaceutical interventions to overcome these barriers. Looking forward, we discussed the latest studies which are expected to reach the clinicals in the next few years, including CRISPR screens-based CAR modification and CAR T cells driven from progenitor-like T cells. Collectively, this review may inspire researchers and clinicians to develop clinical available strategies of CAR T cell therapies in solid tumor.

The preparation of 2,6-disubstituted pyridinyl phosphine oxides as novel anti-cancer agents.

A series of 2,6-dimethoxylpyridinyl phosphine oxides have been synthesized and examined for their antitumor activity. 2,6-Dimethoxy-3-phenyl-4-diphenylphosphinoylpyridine 2 has been employed as the lead compound for this study. We found out that the presence of phosphine oxide on the 2,6-dimethoxylpyridine ring is important for the antitumor activity; the presence of bromine on this core leads to a further enhancement of its antitumor activity. This is the first reported work on the antitumor activity of the 2,6-dimethoxy-3,5-dibromopyridinyl phosphine oxide 5b towards MDAMB-231 breast cancer and SKHep-1 hepatoma cell lines.

FAM134B promotes esophageal squamous cell carcinoma in vitro and its correlations with clinicopathologic features.

Family with sequence similarity 134, member B (FAM134B) is an autophagy regulator of endoplasmic reticulum first discovered to be involved in the pathogenesis of esophageal squamous cell carcinoma (ESCC). The present study examined the functional behavior of FAM134B in cancer cells and the association of FAM134B expression with clinicopathologic factors in patients with ESCC. Expression at both the mRNA and protein levels was investigated using real-time polymerase chain reaction and immunohistochemistry. The results were correlated with the clinical and pathological features of the patients. In addition, in vitro functional assays were used to investigate the roles of FAM134B in ESCC cells in response to gene silencing with shRNA lentiviral particles. Overexpression of FAM134B mRNA and protein was present in 31.2% (n = 29/93) and 36.6% (n = 41/112), respectively, in tumors, whereas downregulation occurred in 39.8% (n = 37/93) and 63.4% (n = 71/112), respectively. Expression of FAM134B protein in ESCC correlated with histologic grade (P = .002) and pathologic stage (P = .012). In vitro suppression of FAM134B in ESCC induced significant reductions of cell proliferation and colony formation (P < .05). In addition, suppression of FAM134B caused reduction of wound healing, migration, and invasion capacities of ESCC. To conclude, FAM134B could play crucial roles in the initiation and progression of ESCC, and FAM134B protein expression has potential predictive value. Therefore, development of strategies targeting FAM134B could have therapeutic value in the management of patients with ESCC.

Development of a Novel Quinoline Derivative as a P-Glycoprotein Inhibitor to Reverse Multidrug Resistance in Cancer Cells.

Multidrug resistance (MDR) is one of conventional cancer chemotherapy's limitations. Our group previously synthesized a series of quinoline-based compounds in an attempt to identify novel anticancer agents. With a molecular docking analysis, the novel compound 160a was predicted to target p-glycoprotein, an MDR candidate. The purpose of this study is to evaluate 160a's MDR reversal effect and investigate the underlying mechanism at the molecular level. To investigate 160a's inhibitory effect, we used a series of parental cancer cell lines (A549, LCC6, KYSE150, and MCF-7), the corresponding doxorubicin-resistant cell lines, an MTS cytotoxicity assay, an intracellular doxorubicin accumulation test, and multidrug resistance assays. The Compusyn program confirmed, with a combination index (CI) value greater than 1, that 160a combined with doxorubicin exerts a synergistic effect. Intracellular doxorubicin accumulation and transported calcein acetoxymethyl (AM) (a substrate for p-glycoprotein) were both increased when cancer cells with MDR were treated with compound 160a. We also showed that compound 160a's MDR reversal effect can persist for at least 1 h. Taken together, these results suggest that the quinoline compound 160a possesses high potential to reverse MDR by inhibiting p-glycoprotein-mediated drug efflux in cancer cells with MDR.

In vitro cytotoxicity of (-)-EGCG octaacetate on MDAMB-231 and SKHep-1 human carcinoma cells: a pharmacological consideration on prodrug design.

Esterification of acetate with generic pharmaceutical compound has been commonly employed to produce ester prodrug for improving its potency when compared with the mother compound. Acetate, on the other hand, has been recognized to have inhibitory effect on the respiratory biochemistry. Here we demonstrate that acetate at a concentration of 400 microM exhibited significant growth inhibitory activity on two human cancer cell lines, the MDAMB-231 breast cancer and the SKHep-1 hepatoma cell lines. To establish the ester prodrug with multi-acetate ester conjugates as our experimental model, one molecule of (-)-epigallocatechin gallate was required to conjugate with eight molecules of acetate forming the corresponding (-)-epigallocatechin gallate octaacetate prodrug. Chemical structure of this epigallocatechin gallate octaacetate ester prodrug was confirmed by both 13C and 1H nuclear magnetic resonance spectra and mass spectrometry. Further cytotoxic assay using both MDAMB-231 and SKHep-1 human carcinoma cell lines showed that acetate at a concentration of 400 microM exhibits an additional cytotoxic effect with (-)-epigallocatechin gallate at a concentration of 50 microM, although the additional effect was not as high as (-)-epigallocatechin gallate octaacetate ester prodrug alone at a concentration of 50 microM. Our results thus raise a pharmacological consideration of using multi-acetate conjugate as the ester prodrug where the release of free acetate by esterase could be part of the explanation for the improved in vitro cytotoxicity.

Synthesis and anti-cancer activity of benzothiazole containing phthalimide on human carcinoma cell lines.

Phthalic anhydride is a highly toxic substance, facing, however, the problem of hydrolysis. In fact, it is rapidly hydrolyzed in aqueous medium, generating phthalic acid as the final product, which is almost harmless to viable cells. Here we describe the 'one pot' condensation reaction for the synthesis of phthalic imide derivative (benzothiazole containing phthalimide), exhibiting in vitro cytotoxic potential on human cancer cell lines. We further demonstrated that both caspase-dependent and -independent pathways are involved in our novel benzothiazole containing phthalimide induced apoptosis on cancer cells.

Expression of Insulin-Like Growth Factor Binding Protein-5 (IGFBP5) Reverses Cisplatin-Resistance in Esophageal Carcinoma.

Cisplatin (CDDP) is one of the front-line chemotherapeutic drugs used in the treatment of esophageal squamous cell carcinoma (ESCC). Occurrence of resistance to CDDP has become one of the main challenges in cancer therapy. In this study, the gene expression profile of CDDP-resistant ESCC cells was investigated and molecular approaches were explored in an attempt to reverse the CDDP resistance. A CDDP-resistant SLMT-1/CDDP1R cell line was established from SLMT-1 cells by subculturing in the medium containing an increasing concentration of CDDP (0.1⁻1µg/mL). Mitochondrial (MTS) cytotoxicity assay, cell proliferation assay and cell morphology were used to assess the acquisition of cisplatin-resistance. The most differentially expressed gene in SLMT-1/CDDP1R cells was identified by cDNA microarray analysis compared with the parental SLMT-1 cells and validated by quantitative real-time polymerase chain reaction (qPCR). Association between expression of the most differentially expressed target gene to cisplatin-resistance was verified by RNA interference. An attempt to reversecisplatin-resistance phenotypes was made by using the vector expressing the most downregulated target gene in the CDDP-resistant cells. A CDDP-resistant ESCC cell line, SLMT-1/CDDP1R, was established with 2.8-fold increase CDDP-resistance (MTS50 = 25.8 µg/mL) compared with the parental SLMT-1 cells. cDNA microarray analysis revealed that IGFBP5 showed the highest level of downregulation in SLMT-1/CDDP1R cells compared with the parental SLMT-1 cells. Suppression of IGFBP5 mediated by IGFBP5-targeting siRNA in parental SLMT-1 cells confirmed that IGFBP5 suppression in ESCC cells would induce CDDP-resistance. More importantly, upregulation of IGFBP5 using IGFBP5 expression vector reduced cisplatin-resistance in SLMT-1/CDDP1R cells by 41%. Thus, our results demonstrated that IGFBP5 suppression is one of the mechanisms for the acquisition of cisplatin-resistance in ESCC cells. Cisplatin-resistance phenotype can be reversed by increasing the expression level of IGFBP5. The overall findings of this study thus offered a new direction for reversing the CDDP resistance in ESCC and possibly in other cancer types with further investigations in future.

Targeting DNA Binding for NF-κB as an Anticancer Approach in Hepatocellular Carcinoma.

Quinoline core has been shown to possess a promising role in the development of anticancer agents. However, the correlation between its broad spectrum of bioactivity and the underlying mechanism of actions is poorly understood. The present study, with the use of bioinformatics approaches, reported a series of designed molecules which integrated quinoline core and sulfonyl moiety, with the objective of evaluating the substituent and linker effects on anticancer activities and associated mechanistic targets. We identified potent compounds (1h, 2h, 5 and 8) exhibiting significant anticancer effects towards liver cancer cells (Hep3B) with the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) relative values of cytotoxicity below 0.40, a value in the range of doxorubicin positive control with the value of 0.12. Bulky substituents and the presence of bromine atom, as well as the presence of sulfonamide linkage, are likely the favorable structural components for molecules exerting a strong anticancer effect. To the best of our knowledge, our findings obtained from chemical synthesis, in vitro cytotoxicity, bioinformatics-based molecular docking analysis (similarity ensemble approach, SEA),and electrophoretic mobility shift assay provided the first evidence in correlation to the anticancer activities of the selected compound 5 with the modulation on the binding of transcription factor NF-κB to its target DNA. Accordingly, compound 5 represented a lead structure for the development of quinoline-based NF-κB inhibitors and this work added novel information on the understanding of the mechanism of action for bioactive sulfonyl-containing quinoline compounds against hepatocellular carcinoma.

Stabilization of G-quadruplex DNA and down-regulation of oncogene c-myc by quindoline derivatives.

Stabilization of G-quadruplex structures in the promoter region of certain oncogenes is an emerging field in anticancer drug design. Human c-myc gene is one of these oncogenes, and G-quadruplexes have been proven to be the transcriptional controller of this gene. In the present study, the interaction of quindoline derivatives with G-quadruplexes in c-myc was investigated. The experimental results indicated that these derivatives have the ability to induce/stabilize the G-quadruplexes in c-myc, which lead to down-regulation of the c-myc in the Hep G2 cell line. It was found that derivatives with terminal amino groups in their side chains would selectively bind to the isomers with the double nucleotide loops in the absence of K+. Molecular modeling studies revealed the binding mode between the derivatives and the G-quadruplexes is end-stacking at the 3'-position, and the positively charged side chain on the quindoline derivatives may contribute to the selectivity to certain loop isomers of topological quadruplexes as well as the improved stabilization action.

Paradoxical proliferative potential of iron (II) sulphate on cancer cells after the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay.

There are several scientific approaches for the determination of cellular growth influences of known or novel substances under in vitro conditions, among which colourimetric absorption measurement is considered to be one of the convenient methods. [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] (MTS) assay is one of the commonly used colourimetric absorption assays based on the ability of dehydrogenase from viable cells to produce the brown soluble formazan detectable at 490 nm. Here we have tested the possible growth influence of iron (II) sulphate on two human cancer cell lines, the K562 chronic myelogenous leukaemia and T47D breast carcinoma cells, based on the MTS assay. We found that iron (II) sulphate possessed an inhibitory effect when added at 16- to 125-microM concentrations, but iron (II) sulphate became growth stimulatory when its concentration was further increased to 1000 microM. In addition, a dose-dependent increase in absorbance at the same wavelength was observed when we repeated the experiments without the addition of MTS and phenazine methosulfate. When we further repeated the cell growth determinations using adenosine triphosphate content assay for K562 and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for T47D, iron (II) sulphate showed a consistent dose-dependent growth inhibitory effect. Morphological investigation after methylene blue staining clearly demonstrated that iron (II) sulphate, at a concentration of 1000 microM, is cytotoxic to T47D cells. Interestingly, a consistent increment for the absorbance at 490 nm was further observed with increased iron (II) sulphate concentration either in the presence or absence of MTS even in a cell-free environment. Thus we conclude that iron (II) sulphate is actually growth inhibitory and even cytotoxic at high concentrations towards the K562 and T47D cancer cells and the paradoxical proliferative activity of iron (II) sulphate on these two cancer cell lines using the MTS assay was solely due to the oxidation of initial pale green iron (II) to brownish iron (III) during incubation in the aqueous condition.