Synthesis and biological activity of new phthalimides as potential anti-inflammatory agents

An Efficient Synthesis of 1-(1,3-Dioxoisoindolin-2-yl)-3-aryl Urea Analogs as Anticancer and Antioxidant Agents: An Insight into Experimental and In Silico Studies

The present investigation reports the efficient multistep synthesis of 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7a-f) in good yields. All the 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7a-f) were characterized by spectroscopic techniques. Five among the six compounds were tested against 56 cancer cell lines at 10 µM as per the standard protocol. 1-(4-Bromophenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7c) exhibited moderate but significant anticancer activity against EKVX, CAKI-1, UACC-62, MCF7, LOX IMVI, and ACHN with percentage growth inhibitions (PGIs) of 75.46, 78.52, 80.81, 83.48, 84.52, and 89.61, respectively. Compound 7c was found to exhibit better anticancer activity than thalidomide against non-small cell lung, CNS, melanoma, renal, prostate, and breast cancer cell lines. It was also found to exhibit superior anticancer activity against melanoma cancer compared to imatinib. Among the tested compounds, the 4-bromosubstitution (7c) on the phenyl ring demonstrated good anticancer activity. Docking scores ranging from -6.363 to -7.565 kcal/mol were observed in the docking studies against the molecular target EGFR. The ligand 7c displayed an efficient binding against the EGFR with a docking score of -7.558 kcal/mol and displayed an H-bond interaction with Lys745 and the carbonyl functional group. Compound 7c demonstrated a moderate inhibition of EGFR with an IC50 of 42.91 ± 0.80 nM, in comparison to erlotinib (IC50 = 26.85 ± 0.72 nM), the standard drug. The antioxidant potential was also calculated for the compounds (7a-f), which exhibited good to low activity. 1-(2-Methoxyphenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7f) and 1-(4-Methoxyphenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7d) demonstrated significant antioxidant activity with IC50 values of 15.99 ± 0.10 and 16.05 ± 0.15 µM, respectively. The 2- and 4-methoxysubstitutions on the N-phenyl ring showed good antioxidant activity among the series of compounds (7a-f). An in silico ADMET prediction studies showed the compounds' adherence to Lipinski's rule of five: they were free from toxicities, including mutagenicity, cytotoxicity, and immunotoxicity, but not for hepatotoxicity. The toxicity prediction demonstrated LD50 values between 1000 and 5000 mg/Kg, putting the compounds either in class IV or class V toxicity classes. Our findings might create opportunities for more advancements in cancer therapeutics.

Insights into the advances in therapeutic drugs for neuroinflammation-related diseases

Studies have shown that neurodegenerative diseases such as AD and PD are related to neuroinflammation. Neuroinflammation is a common inflammatory condition that can lead to a variety of dysfunction in the body. At present, it is no medications specifically approved to prevent or cure neuroinflammation, so even though many drugs can temporarily control the neurological symptoms of neuroinflammation, but no one can reverse the progress of neuroinflammation, let al.one completely cure neuroinflammation. Therefore, it is urgent to develop new drug development for neuroinflammation treatment. In this review, we highlight the therapeutic advancement in the field of neurodegenerative disorders, by focusing on the impact of neuroinflammation treatment has on these conditions, and the effective drugs for the treatment of neuroinflammation and neurodegenerative diseases and their latest research progress are reviewed according to the related signaling pathway, as well as the prospect of their clinical application is also discussed. The purpose of this review is to enable specialists to better understand the mechanisms underlying neuroinflammation and anti-inflammatory drugs, promote the development of therapeutic drugs for neuroinflammation and neurodegenerative diseases, and further provide therapeutic references for clinical neurologists.

Spectroscopic and Theoretical Analysis of the Interaction between Plasma Proteins and Phthalimide Analogs with Potential Medical Application

One of the groups of organic compounds with potential use in medicine and pharmacy is phthalimide derivatives. They are characterized by a wide range of properties such as antibacterial, antifungal, and anti-inflammatory. In this study, we focused on research on four phthalimide derivatives with proven non-toxicity, which are cyclooxygenase inhibitors. With the use of molecular docking study and spectroscopic methods, such as fluorescence, circular dichroism, and FT-IR spectroscopies, we analyzed the way the tested compounds interact with plasma proteins. Among the many proteins present in the plasma, we selected three: albumin, α1-acid glycoprotein, and gamma globulin, which play significant roles in the human body. The obtained results showed that all tested compounds bind to the analyzed proteins. They interact most strongly with albumin, which is a transport protein. However, interactions with serum albumin and orosomucoid do not cause significant changes in their structures. Only in the case of gamma globulins significant changes were observed in protein secondary structure.

Antimicrobial Agents Based on Metal Complexes: Present Situation and Future Prospects

The rise in antimicrobial resistance is a cause of serious concern since the ages. Therefore, a dire need to explore new antimicrobial entities that can combat against the increasing threat of antibiotic resistance is realized. Studies have shown that the activity of the strongest antibiotics has reduced drastically against many microbes such as microfungi and bacteria (Gram-positive and Gram-negative). A ray of hope, however, was witnessed in early 1940s with the development of new drug discovery and use of metal complexes as antibiotics. Many new metal-based drugs were developed from the metal complexes which are potentially active against a number of ailments such as cancer, malaria, and neurodegenerative diseases. Therefore, this review is an attempt to describe the present scenario and future development of metal complexes as antibiotics against wide array of microbes.

The in vitro anti-inflammatory activity of N-antipyrine-3,4-dichloromaleimide derivatives is due to an immunomodulatory effect on cytokines environment

BACKGROUND AND AIM

Inflammation is the immune response to a harmful stimulus, and its purpose is to destroy foreign agents so that the affected site can be repair. When uncontrolled or unresolved, inflammation can lead to significant tissue damage. Many classes of compounds are used today as anti-inflammatory drugs. However, there is an ongoing demand for new, more effective molecules with higher safety margins. In this regard, the anti-inflammatory effect of six synthetic compounds of N-antipyrine-3,4-dichloromaleimide was evaluated.

METHODS

RAW 264.7 cells were used to evaluate the cytotoxicity and the anti-inflammatory activity, by measuring the effect of these molecules on nitric oxide, IL-1β, IL-6, MCP-1 (CCL2), TNF-α, INF-γ, IL-4, and IL-13 levels, as well as under NF-κB activation.

RESULTS

Some of the tested compounds showed significant cytotoxicity (CC50 < 100 µM). Subsequently, the potential of nitric oxide (NO) inhibition as screening for potential anti-inflammatory action was evaluated. Three of the compounds tested showed a promising profile (1, 3, and 5). When the effect of these compounds was evaluated on the production of IL-1β, IL-6, MCP-1 (CCL2), TNF-α, and INF-γ, only N-antipyrine-3,4-dichloromaleimide (1) and N-antipyrine-3-chloro-4-(3,4-dichloroaniline) maleimide (3) showed significant inhibition profiles. These two compounds were also able to increase the production of cytokines known for having an anti-inflammatory profile (IL-4 and IL-13) and inhibit the phosphorylation of the p-p65 NF-κB subunit significantly.

CONCLUSION

In conclusion, these two compounds present a significant and unusual anti-inflammatory mechanism (increasing the production of anti-inflammatory mediators). They are therefore considered promising prototypes for the development of new anti-inflammatory drugs with immunomodulatory characteristics.

New phthalimide analog ameliorates CCl4 induced hepatic injury in mice via reducing ROS formation, inflammation, and apoptosis

The present study aimed, for the first time, to examine the biochemical effects of new phthalimide analog, 2-[2-(2-Bromo-1-ethyl-1H-indol-3-yl) ethyl]-1H-isoindole-1,3(2H)-dione, compared to thalidomide drug against liver injury induced in mice. Carbon tetrachloride was intraperitoneal injected in mice for 6 consecutive weeks at a dose of 0.4 mL/kg twice a week for liver injury induction. Histopathological examination, levels of malondialdehyde, nitric oxide, and antioxidant enzymes were determined. Additionally, the protein levels of vascular endothelial growth factor, proliferating cell nuclear protein, tumor necrosis factor-alfa, nuclear factor kappa B-p65, B-cell lymphoma-2, and cysteine-aspartic acid protease-3 were determined. Results revealed that the treatment with phthalimide analog improved the detected liver damage and presented an obvious antioxidant activity through decreasing malondialdehyde and nitric oxide levels accompanied by increasing the levels of the antioxidant enzymes. Furthermore, the analog exhibited an effective inhibitory activity towards the studied protein expressions in liver tissues. Moreover, the B-cell lymphoma-2 protein level was increased while the cysteine-aspartic acid protease-3 level was suppressed after the treatment with phthalimide analog. Together, these results propose that phthalimide analog can ameliorate carbon tetrachloride-induced liver injury in mice through its potent inhibition mediating effect in oxidative stress, inflammation, and apoptosis mechanisms.

A New N-Substituted 1H-Isoindole-1,3(2H)-Dione Derivative-Synthesis, Structure and Affinity for Cyclooxygenase Based on In Vitro Studies and Molecular Docking

Isoindoline-1,3-dione derivatives constitute an important group of medicinal substances. In this study, nine new 1H-isoindole-1,3(2H)-dione derivatives and five potential pharmacophores were obtained in good yield (47.24–92.91%). The structure of the new imides was confirmed by the methods of elemental and spectral analysis: FT–IR, H NMR, and MS. Based on the obtained results of ESI–MS the probable path of the molecules decay and the hypothetical structure of the resulting pseudo-molecular ions have been proposed. The physicochemical properties of the new phthalimides were determined on the basis of Lipiński’s rule. The biological properties were determined in terms of their cyclooxygenase (COX) inhibitory activity. Three compounds showed greater inhibition of COX-2, three compounds inhibited COX-1 more strongly than the reference compound meloxicam. From the obtained results, the affinity ratio COX-2/COX-1 was calculated. Two compounds had a value greater than that of meloxicam. All tested compounds showed oxidative or nitrosan stress (ROS and RNS) scavenging activity. The degree of chromatin relaxation outside the cell nucleus was lower than the control after incubation with all test compounds. The newly synthesized phthalimide derivatives showed no cytotoxic activity in the concentration range studied (10–90 µM). A molecular docking study was used to determined interactions inside the active site of cyclooxygenases.

Design of molecular hybrids of phthalimide-triazole agents with potent selective MCF-7/HepG2 cytotoxicity: Synthesis, EGFR inhibitory effect, and metabolic stability

This study reports an efficient and convenient click chemistry synthesis of a novel series of phthalimide scaffold linked to 1,2,3 triazole ring and terminal lipophilic fragments. Structures of newly synthesized compounds were well characterized by different spectroscopic tools. In vitro MTT cytotoxicity assay was performed comparing the cytotoxic effects of newly synthesized compounds to staurosporine using three different types: human liver cancer cell line (HepG2), Michigan cancer foundation-7 (MCF-7) and human colorectal carcinoma cell line (HCT116). The initial screening showed excellent to moderate anticancer activity for these newly synthesized compounds with high degree of cell line selectivity with micromolar (µM) half maximal inhibitory concentration (IC₅₀) values against tumor cells. The SAR analysis of these derivatives confirmed the role of molecular fragments including phthalimide, linker, triazole, and terminal tails in correlation to activity. In addition, enzymatic inhibitory assay against wild type EGFR was performed for the most active compounds to get more details about their mechanism of action. In order to further explore their binding affinities, molecular docking simulation was studied against EGFR site. The results obtained from molecular docking study and those obtained from cytotoxic screening were correlated. One of the most prominent analogs is (6f) with terminal disubstituted ring and amide linker showed selective MCF-7 cytotoxicity profile with IC₅₀ 0.22 µM and 79 nM to EGFR target. Extensive structure activity relationship (SAR) analyses were also carried out. The pharmacokinetic profile of (6f) was studied showing good metabolic stability and long duration behavior. This design offered a potent selective anticancer phthalimide-triazole leads for further optimization in cancer drug discovery.

Synthesis of 4-(3-oxo-3-phenylpropyl)morpholin-4-ium chloride analogues and their inhibitory activities of nitric oxide production in lipopolysaccharide-induced BV2 cells

Based on our previous report that 3-morpholino-1-phenylpropan-1-one 2, one of the fluoxetine's simplified morpholino analogue, inhibited nitric oxide (NO) production, in this paper, various substituted benzene analogues with morpholine hydrochloride of 2 were synthesized and their inhibitory effects on NO production in lipopolysaccharide (LPS)-induced BV2 cells were tested. Among the synthesized compounds, 2-trifluoromethyl analogue 16n (IC₅₀ = 8.6 μM) showed a significantly higher inhibitory activity than that of the parent compound 2a (IC₅₀ > 50 μM) and suppressed NO production dose-dependently without cytotoxicity. Compound 16n also inhibited iNOS expression in LPS-induced BV2 cells at 2, 10 and 20 μM concentrations. These results suggest that compound 16n inhibited NO production by suppressing the expression of iNOS and can be used as a lead structure for developing new inhibitor of NO production.

Development of a caffeic acid–phthalimide hybrid compound for NADPH oxidase inhibition

NADPH oxidases are pharmacological targets for the treatment of inflammation-based diseases. This work presents the synthesis and study of a caffeic acid/phthalimide hybrid compound (C2) as a potential inhibitor of NADPH oxidases. Throughout the study, we have compared compound C2 with its precursor caffeic acid (C1). The redox properties were compared using three different antioxidant methodologies and showed that C2 was slightly less effective than C1, a well-established and robust antioxidant. However, C2 was three-fold more effective than albumin (used as a model protein). This chemical feature was decisive for the higher efficiency of C2 as an inhibitor of the release of superoxide anions by stimulated neutrophils and enzymatic activity of cell-free NADPH oxidase. Docking simulation studies were performed using the crystal structure of the recombinant dehydrogenase domain of the isoform NOX5 of C. stagnale, which retains the FAD cofactor (PDB: 5O0X). Considering that C2 could bind at the FAD redox site of NOX5, studies were conducted by comparing the interactions and binding energies of C1 and C2. The binding energies were −50.30 (C1) and −74.88 (C2) (kJ mol⁻¹), which is in agreement with the higher efficacy of the latter as an NADPH oxidase inhibitor. In conclusion, incorporating the phthalimide moiety into caffeic acid was decisive for its effectiveness as an NADPH oxidase inhibitor.

The incorporation of the phthalimide moiety into caffeic acid was decisive for its effectiveness as an NADPH oxidase inhibitor.

New Antimicrobial Strategies Based on Metal Complexes

Traditional organic antimicrobials mainly act on specific biochemical processes such as replication, transcription and translation. However, the emergence and wide spread of microbial resistance is a growing threat for human beings. Therefore, it is highly necessary to design strategies for the development of new drugs in order to target multiple cellular processes that should improve their efficiency against several microorganisms, including bacteria, viruses or fungi. The present review is focused on recent advances and findings of new antimicrobial strategies based on metal complexes. Recent studies indicate that some metal ions cause different types of damages to microbial cells as a result of membrane degradation, protein dysfunction and oxidative stress. These unique modes of action, combined with the wide range of three-dimensional geometries that metal complexes can adopt, make them suitable for the development of new antimicrobial drugs.

Molecular Hybrids of N-Phthaloylglycyl Hydrazide and Hydrazinecarbothioamide with Anti-inflammatory and Anti-oxidant Activities

BACKGROUND

Oxidative stress due to high levels of reactive organic species is the cause of the progression of inflammation in various diseases. The molecules possessing both anti-inflammatory and antioxidant activity can be the promising key to treat inflammatory diseases. Phthalimide and hydrazinecarbothioamide are anti-inflammatory and anti-oxidant pharmacophores.

OBJECTIVE

Molecular hybrids possessing above two pharmacophores were designed. A series of N-phenyl substituted 2-(2-(1,3-dioxoisoindolin-2-yl)acetyl)-N-phenylhydrazine-1-carbothioamide (CGS compounds) was synthesized and evaluated for biological activities.

METHODS

N-phthaloylglycyl hydrazide was reacted with unsubstituted/substituted phenyl isothiocyanates to yield CGS compounds. Synthesized compounds were evaluated for in vivo anti-inflammatory activity in carrageenan rat paw edema model, and in vitro anti-oxidant activity by DPPH assay. Levels of TNF-α and oxidative stress at the site of inflammation were measured. The genetic algorithm-PLS regression based QSAR model correlating the effect of N-phenyl substituent on the anti-inflammatory activity was developed. Further, the interaction of the active compound in the TNF-α binding pocket was studied by in silico docking.

RESULTS

Compound containing the 2-OCH3, 4-NO2 (CGS-5); 4-CF3 (CGS-9); 4-NO2 (CGS-3) showed significant anti-inflammatory activity (percentage inhibition of paw edema after 3 hour = 58.24, 50.38, 40.05, respectively) and potent anti-oxidant activity (IC50 =0.045, 0.998, 0.285 μg/ml, respectively). Reduced levels of TNF- α and increased levels of GSH were observed for the above three compounds. Descriptors for QSAR model identified by GA-PLS were WPSA1, Weta1unity, WDunity, SC3, VC5, MlogP, and WTPT3. The identified model was highly predictive, and value of root mean square error of prediction for internal (leave one out) and external validation was: 1.579, 1.325.

CONCLUSION

Molecular hybrids of phthalimide and hydrazinecarbothioamide were synthesized. Some of the compounds possessed promising anti-inflammatory and anti-oxidant activities.

Design, synthesis and bioevaluation of novel 6-substituted aminoindazole derivatives as anticancer agents

In the present study, a series of 6-substituted aminoindazole derivatives were designed, synthesized, and evaluated for bio-activities. The compounds were initially designed as indoleamine 2,3-dioxygenase 1 (IDO1) inhibitors based on the structural feature of five IDO1 inhibitors, which are currently on clinical trials, and the important anticancer activity of the indazole scaffold. One of them, compound N-(4-fluorobenzyl)-1,3-dimethyl-1H-indazol-6-amine (36), exhibited a potent anti-proliferative activity with an IC₅₀ value of 0.4 ± 0.3 μM in human colorectal cancer cells (HCT116). This compound also remarkably suppressed the IDO1 protein expression. In the cell-cycle studies, the suppressive activity of compound 36 in HCT116 cells was related to the G2/M cell cycle arrest. Altogether, the current findings demonstrate that compound 36 would be promising for further development as a potential anticancer agent.

In the present study, a series of 6-substituted aminoindazole derivatives were designed, synthesized, and evaluated for bio-activities.

The phthalimide analogues N-3-hydroxypropylphthalimide and N-carboxymethyl-3-nitrophthalimide exhibit activity in experimental models of inflammatory and neuropathic pain

BACKGROUND

Phthalimide analogues devoid of the glutarimide moiety exhibit multiple biological activities, thus making them candidates for the treatment of patients with different diseases, including those with inflammatory and painful disorders. In the present study, the activities of five phthalimide analogues devoid of the glutarimide moiety (N-hydroxyphthalimide, N-hydroxymethylphthalimide, N-3-hydroxypropylphthalimide, N-carboxy-3-methylphthalimide, N-carboxymethyl-3-nitrophthalimide) were evaluated in experimental models of acute and chronic inflammatory and neuropathic pain.

METHODS

The phthalimide analogues were administered per os (po) in Swiss mice or Wistar rats. Nociceptive response induced by formaldehyde and mechanical allodynia induced by chronic constriction injury (CCI) of the sciatic nerve or intraplantar (ipl) injection of complete Freund's adjuvant (CFA) were used as experimental models of pain.

RESULTS

N-carboxymethyl-3-nitrophthalimide (700 mg/kg, -1 h) inhibited the second phase of the nociceptive response induced by the intraplantar injection of formaldehyde in mice. N-3-hidroxypropylphthalimide (546 mg/kg, -1 h) inhibited both phases of the nociceptive response induced by formaldehyde. Treatment of rats with N-carboxymethyl-3-nitrophthalimide (700 mg/kg) or N-3-hydroxypropylphthalimide (546 mg/kg) inhibited the mechanical allodynia induced by CCI of the sciatic nerve or ipl injection of CFA in rats. Intraperitoneal administration of the opioid antagonist naltrexone (10 mg/kg, -1.5 h) attenuated the antinociceptive activity of N-carboxymethyl-3-nitrophthalimide (700 mg/kg) in the model of nociceptive response induced by formaldehyde.

CONCLUSIONS

N-3-hydroxypropylphthalimide and N-carboxymethyl-3-nitrophthalimide, two phthalimide analogues devoid of the glutarimide moiety, exhibited activities in different experimental models of pain, including models of chronic inflammatory and neuropathic pain.

The Potential Impacts of Tylophora Alkaloids and their Derivatives in Modulating Inflammation, Viral Infections, and Cancer

Cancer chemotherapies or antitumor agents mainly remain the backbone of current treatment based on killing the rapidly dividing cancer cell such as tylophora alkaloids and their analogues which have also demonstrated anticancer potential through diverse biological pathways including regulation of the immune system. The introduction of durable clinically effective monoclonal antibodies, however, unmasked a new era of cancer immunotherapies. Therefore, the understanding of cancer pathogenesis will provide new possible treatment options, including cancer immunotherapy and targeted agents. Combining cytotoxic agents and immunotherapies may offer several unique advantages that are complementary to and potentially synergistic with biologic modalities. Herein, we highlight the dynamic mechanism of action of immune modulation in cancer and the immunological aspects of the orally active antitumor agents tylophora alkaloids and their analogues. We also suggest that future cancer treatments will rely on the development of combining tumor-targeted agents and biologic immunotherapies.

Circular RNAs in Cancer

Circular RNAs (circRNAs) are a class of single-stranded closed RNA molecules that are formed by precursor mRNA back-splicing or skipping events of thousands of genes in eukaryotes as covalently closed continuous loops. High-throughput sequencing and bioinformatics approaches have uncovered the broad expression of circRNAs across species. Their high stability, abundance, and evolutionary conservation among species points to their distinct properties and diverse cellular functions as efficient microRNAs and protein sponges; they also play important roles in modulating transcription and splicing. Additionally, most circRNAs are aberrantly expressed in pathological conditions and in a tissue-specific manner such as development and progression of cancer. Herein, we highlight the characteristics, functions, and mechanisms of action of circRNAs in cancer; we also provide an overview of recent progress in the circRNA field and future application of circRNAs as cancer biomarkers and novel therapeutic targets.

The Role of Platelets in the Tumor-Microenvironment and the Drug Resistance of Cancer Cells

Besides the critical functions in hemostasis, thrombosis and the wounding process, platelets have been increasingly identified as active players in various processes in tumorigenesis, including angiogenesis and metastasis. Once activated, platelets can release bioactive contents such as lipids, microRNAs, and growth factors into the bloodstream, subsequently enhancing the platelet⁻cancer interaction and stimulating cancer metastasis and angiogenesis. The mechanisms of treatment failure of chemotherapeutic drugs have been investigated to be associated with platelets. Therefore, understanding how platelets contribute to the tumor microenvironment may potentially identify strategies to suppress cancer angiogenesis, metastasis, and drug resistance. Herein, we present a review of recent investigations on the role of platelets in the tumor-microenvironment including angiogenesis, and metastasis, as well as targeting platelets for cancer treatment, especially in drug resistance.

BMP4 Upregulation Is Associated with Acquired Drug Resistance and Fatty Acid Metabolism in EGFR-Mutant Non-Small-Cell Lung Cancer Cells

Lung cancer is the leading cause of cancer-associated deaths worldwide. In particular, non-small-cell lung cancer (NSCLC) cells harboring epidermal growth factor receptor (EGFR) mutations are associated with resistance development of EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment. Recent findings suggest that bone morphogenetic proteins (BMPs) and microRNAs (miRNAs) might act as oncogenes or tumor suppressors in the tumor microenvironment. In this study, for the first time, we identified the potential roles of BMPs and miRNAs involved in EGFR-TKI resistance by analyzing datasets from a pair of parental cells and NSCLC cells with acquired EGFR-TKI resistance. BMP4 was observed to be significantly overexpressed in the EGFR-TKI-resistant cells, and its mechanism of action was strongly associated with the induction of cancer cell energy metabolism through the modulation of Acyl-CoA synthetase long-chain family member 4. In addition, miR-139-5p was observed to be significantly downregulated in the resistant NSCLC cells. The combination of miR-139-5p and yuanhuadine, a naturally derived antitumor agent, synergistically suppressed BMP4 expression in the resistant cells. We further confirmed that LDN-193189, a small molecule BMP receptor 1 inhibitor, effectively inhibited tumor growth in a xenograft nude mouse model implanted with the EFGR-TKI-resistant cells. These findings suggest a novel role of BMP4-mediated tumorigenesis in the progression of acquired drug resistance in EGFR-mutant NSCLC cells.

Discovery of Pyrazolo[4,3-c]quinolines Derivatives as Potential Anti-Inflammatory Agents through Inhibiting of NO Production

The synthesis and anti-inflammatory effects of certain pyrazolo[4,3-c]quinoline derivatives 2a–2r are described. The anti-inflammatory activities of these derivatives were evaluated by means of inhibiting nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Among them, 3-amino-4-(4-hydroxyphenylamino)-1H-pyrazolo[4,3-c]-quinoline (2i) and 4-(3-amino-1H-pyrazolo[4,3-c]quinolin-4-ylamino)benzoic acid (2m) exhibited significant inhibition of LPS-stimulated NO production with a potency approximately equal to that of the positive control, 1400 W. Important structure features were analyzed by quantitative structure–activity relationship (QSAR) analysis to give better insights into the structure determinants for predicting the inhibitory effects on the accumulation of nitric oxide for RAW 264.7 cells in response to LPS. In addition, our results indicated that their anti-inflammatory effects involve the inhibition of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) protein expression. Further studies on the structural optimization are ongoing.

Targeting Nicotinamide N-Methyltransferase and miR-449a in EGFR-TKI-Resistant Non-Small-Cell Lung Cancer Cells

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are used clinically as target therapies for lung cancer patients, but the occurrence of acquired drug resistance limits their efficacy. Nicotinamide N-methyltransferase (NNMT), a cancer-associated metabolic enzyme, is commonly overexpressed in various human tumors. Emerging evidence also suggests a crucial loss of function of microRNAs (miRNAs) in modulating tumor progression in response to standard therapies. However, their precise roles in regulating the development of drug-resistant tumorigenesis are still poorly understood. Herein, we established EGFR-TKI-resistant non-small-cell lung cancer (NSCLC) models and observed a negative correlation between the expression levels of NNMT and miR-449a in tumor cells. Additionally, knockdown of NNMT suppressed p-Akt and tumorigenesis, while re-expression of miR-449a induced phosphatase and tensin homolog (PTEN), and inhibited tumor growth. Furthermore, yuanhuadine, an antitumor agent, significantly upregulated miR-449a levels while critically suppressing NNMT expression. These findings suggest a novel therapeutic approach for overcoming EGFR-TKI resistance to NSCLC treatment.