309 research outputs found
Novel quinazoline-based sulfonamide derivative (3D) induces apoptosis in colorectal cancer by inhibiting JAK2–STAT3 pathway
Introduction: Colorectal cancer (CRC) is a major worldwide health problem owing to its high
prevalence and mortality rate. Developments in screening, prevention, biomarker, personalized
therapies and chemotherapy have improved detection and treatment. However, despite these
advances, many patients with advanced metastatic tumors still succumb to the disease. New
anticancer agents are needed for treating advanced stage CRC as most of the deaths occur due to
cancer metastasis. A recently developed novel sulfonamide derivative 4-((2-(4-(dimethylamino)
phenyl)quinazolin-4-yl)amino)benzenesulfonamide (3D) has shown potent antitumor effect;
however, the mechanism underlying the antitumor effect remains unknown.
Materials and methods: 3D-mediated inhibition on cell viability was evaluated by MTT and
real-time cell proliferation was measured by xCelligence RTDP instrument. Western blotting
was used to measure pro-apoptotic, anti-apoptotic proteins and JAK2-STAT3 phosphorylation.
Flow cytometry was used to measure ROS production and apoptosis.
Results: Our study revealed that 3D treatment significantly reduced the viability of human CRC
cells HT-29 and SW620. Furthermore, 3D treatment induced the generation of reactive oxygen
species (ROS) in human CRC cells. Confirming our observation, N-acetylcysteine significantly
inhibited apoptosis. This is further evidenced by the induction of p53 and Bax; release of cytochrome
c; activation of caspase-9, caspase-7 and caspase-3; and cleavage of PARP in 3D-treated cells. This
compound was found to have a significant effect on the inhibition of antiapoptotic proteins Bcl2 and
BclxL. The results further demonstrate that 3D inhibits JAK2–STAT3 pathway by decreasing the
constitutive and IL-6-induced phosphorylation of STAT3. 3D also decreases STAT3 target genes
such as cyclin D1 and survivin. Furthermore, a combination study of 3D with doxorubicin (Dox)
also showed more potent effects than single treatment of Dox in the inhibition of cell viability.
Conclusion: Taken together, these findings indicate that 3D induces ROS-mediated apoptosis
and inhibits JAK2–STAT3 signaling in CRC
Carbonic anhydrase inhibitors targeting metabolism and tumor microenvironment
The tumor microenvironment is crucial for the growth of cancer cells, triggering particular biochemical and physiological changes, which frequently influence the outcome of anticancer therapies. The biochemical rationale behind many of these phenomena resides in the activation of transcription factors such as hypoxia-inducible factor 1 and 2 (HIF-1/2). In turn, the HIF pathway activates a number of genes including those involved in glucose metabolism, angiogenesis, and pH regulation. Several carbonic anhydrase (CA, EC 4.2.1.1) isoforms, such as CA IX and XII, actively participate in these processes and were validated as antitumor/antimetastatic drug targets. Here, we review the field of CA inhibitors (CAIs), which selectively inhibit the cancer-associated CA isoforms. Particular focus was on the identification of lead compounds and various inhibitor classes, and the measurement of CA inhibitory on-/off-target effects. In addition, the preclinical data that resulted in the identification of SLC-0111, a sulfonamide in Phase Ib/II clinical trials for the treatment of hypoxic, advanced solid tumors, are detailed
Metabolomic profile, anti-trypanosomal potential and molecular docking studies of <i>Thunbergia grandifolia</i>
Trypanosomiasis is a protozoan disease transmitted via Trypanosoma brucei. This study aimed to examine the metabolic profile and anti-trypanosomal effect of methanol extract of Thunbergia grandifolia leaves. The liquid chromatography-high resolution electrospray ionisation mass spectrometry (LC-HRESIMS) revealed the identification of fifteen compounds of iridoid, flavonoid, lignan, phenolic acid, and alkaloid classes. The extract displayed a promising inhibitory activity against T. brucei TC 221 with MIC value of 1.90 μg/mL within 72 h. A subsequent in silico analysis of the dereplicated compounds (i.e. inverse docking, molecular dynamic simulation, and absolute binding free energy) suggested both rhodesain and farnesyl diphosphate synthase as probable targets for two compounds among those dereplicated ones in the plant extract (i.e. diphyllin and avacennone B). The absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiling of diphyllin and avacennone were calculated accordingly, where both compounds showed acceptable drug-like properties. This study highlighted the antiparasitic potential of T. grandifolia leaves
Development of novel isatin thiazolyl-pyrazoline hybrids as promising antimicrobials in MDR pathogens
Microbial Multidrug Resistance (MDR) is an emerging global crisis. Derivatization of natural or synthetic
scaffolds is among the most reliable strategies to search for and obtain novel antimicrobial agents for
the treatment of MDR infections. Here, we successfully manipulated the synthetically flexible isatin
moieties to synthesize 22 thiazolyl-pyrazolines hybrids, and assessed their potential antimicrobial
activities in vitro against various MDR pathogens, using the broth microdilution calorimetric XTT
reduction method. We chose 5 strains to represent the major MDR microorganisms, viz: Methicillin
resistant S. aureus (MRSA), and Vancomycin-resistant E. faecalis (VRE) as Gram-positive bacteria;
Carbapenem-resistant K. pneumonia (CRKP), and Extended-spectrum beta-lactamase E. coli (ESBL-E), as
Gram-negative bacteria; and Fluconazole-resistant C. albicans (FRCA), as a yeast-like unicellular fungus.The cytotoxicity of compounds 9f and 10h towards mammalian lung fibroblast (MRC-5) cells demonstrated their potential satisfactory safety margin as represented by their relatively high IC50 values. The target compounds showed promising anti-MDR activities, suggesting they are potential leads for further development and in vivo studies
Novel thiazolidinone/thiazolo[3,2-a] benzimidazolone-isatin conjugates as apoptotic anti-proliferative agents towards breast cancer: One-pot synthesis and in vitro biological evaluation
In connection with our research program on the development of new isatin-based anticancer candidates, herein we report the synthesis of two novel series of thiazolidinone-isatin conjugates (4a-n) and thiazolo[3,2-a]benzimidazolone-isatin conjugates (7a-d), and in vitro evaluation of their antiproliferative activity towards two breast cancer cell lines; triple negative MDA-MB-231, and MCF-7. Compounds 4m and 7b emerged as the most active congeners against MDA-MB-231 cells (IC50= 7.6 ± 0.5 and 13.2 ± 1.1 µM, respectively). Compounds 4m and 7b were able to provoke apoptosis in MDA-MB-231 cells, evidenced by the up-regulation of Bax and down-regulation of Bcl-2, besides boosting caspase-3 levels. Hybrid 4m induced a fourfold increase in the percentage of cells at Sub-G1, with concurrent arrest in G2-M phase by 2.5-folds. Furthermore, hybrid 4m resulted in a sixfold increase in the percentage of annexin V-FITC positive apoptotic MDA-MB-231 cells as compared with the control. Moreover, the cytotoxic activities of the active conjugates were assessed towards two nontumorigenic cell lines (breast MCF-10A and lung WI-38) where both conjugates 4m and 7b displayed mean tumor selectivity index: 9.6 and 13.9, respectively. Finally, several ADME descriptors were predicted for the active conjugates via a theoretical kinetic study
Canal Transportation and Centring Ratio of Paediatric vs Regular Files in Primary Teeth
Background: During mechanical preparation of the primary root canal, the original anatomy of the tooth should be preserved and the instrument should be perfectly balanced centrally into the canal space for reducing the probability of canal transportation. The aim of this research was to compare canal transportation and canal centring ability in primary root canals using ProTaper Next (Dentsply Mailfair,), AF baby (Fanta), and Kidzo Elephant (Endostar, Poldent Sp.) files. Materials and methods: Eighteen root canals were randomly divided into 3 experimental groups (n = 6 in each group). Instrumentation was performed using ProTaper Next, Fanta AF baby, and Kidzo Elephant files in groups 1, 2, and 3, respectively. During the instrumentation procedure, the irrigation of 2 mL of 1.5% sodium hypochlorite between each file was done, followed by 5 mL of 17% ethylenediaminetetraacetic acid as a final irrigating solution. Cone-beam computed tomography images were obtained before and after instrumentation. Each group was evaluated for transportation and centring ratios. Results: On comparing all the tested groups within each root canal level canal transportation, the results revealed a statistically nonsignificant difference in the buccolingual direction (P > 0.05). Meanwhile, in the mesiodistal direction, group 1 showed a statistically highly significant difference compared to groups 2 and 3 at the cervical level (P 0.05). Regarding the centring ability comparison of the 3 groups within each root canal level, there was a statistically nonsignificant difference amongst all groups (P > 0.05) in both buccolingual and mesiodistal directions. Conclusions: The ProTaper Next regular rotary file and the paediatric rotary files showed no difference in canal transportation and centring ability in the buccolingual direction, while in the mesiodistal direction at the cervical root canal level, the ProTaper Next showed high transportation liability
Design, Synthesis and Antitubercular Activity of Certain Nicotinic Acid Hydrazides
Three series of 6-aryl-2-methylnicotinohydrazides 4a–i, N′-arylidene-6-(4-bromophenyl)-2-methylnicotino hydrazides 7a–f, and N′-(un/substituted 2-oxoindolin-3-ylidene)-6-(4-fluorophenyl)-2-methylnicotinohydrazides 8a–c were synthesized and evaluated for their potential in vitro antimycobacterial activity against M. tuberculosis. The results showed that isatin hydrazides 8a–c are remarkably more active than the parent hydrazide 4c. Hydrazides 8b and 8c exhibited the highest activity among all the tested compounds (MIC = 12.5 and 6.25 µg/mL, respectively). Compounds 8b and 8c were also devoid of apparent cytotoxicity to HT-29, PC-3, A549, HepG2 and MCF-7 cancer cell lines. Besides, 8b and 8c showed good drug-likeness scores of 0.62 and 0.41, respectively. Those two isatin hydrazides could offer an excellent framework for future development to obtain more potent antitubercular agents. The SAR study suggested that lipophilicity of the synthesized derivatives is a crucial element that accounts for their antimycobacterial activity. Finally, a theoretical kinetic study was established to predict the ADME of the active derivatives
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