Moxifloxacin and ciprofloxacin induces S-phase arrest and augments apoptotic effects of cisplatin in human pancreatic cancer cells via ERK activation

New series of fluoroquinolone derivatives as potential anticancer Agents: Design, Synthesis, in vitro biological Evaluation, and Topoisomerase II Inhibition

A series of fluoroquinolone analogs (II, IIIa-g) derived from Ciprofloxacin hydrazide were designed, and synthesized. The NCI-60 Human Tumor Cell Line Screening assay indicated that compounds II, IIIb, and IIIf are the most potent among the series and were further selected for five-dose evaluation, where they exhibited potent cytotoxicity with mean GI50 values of 3.30, 2.45, and 9.06 µM, respectively, where they reduced the cell proliferation of most of the tested cell lines with IC50 values significantly lower than the reference drug Etoposide. A selectivity study demonstrated the high selective cytotoxicity of IIIf towards cancerous cells over normal mammalian Vero cells, presenting it as a potent and selective antitumor agent. Cell cycle analysis revealed that treatment with II, IIIb, or IIIf induced cell cycle arrest at the G2/M phase in MCF-7 cells. Topoisomerase II enzyme inhibition assay showed that the three tested compounds are potent topo II inhibitors where compound II (IC50 = 51.66 µM) displayed more potent inhibitory activity compared to the well-known topo II inhibitor Etoposide (IC50 = 58.96 µM), while compounds IIIb and IIIf showed comparable activity to the reference drug. Molecular modeling study suggested that the topoisomerase inhibitory activity may be attributed to the binding to the Merbarone binding site and chelation with Mg2+.

Synergistic Potential of Antibiotics with Cancer Treatments

Intratumoral microbiota, the diverse community of microorganisms residing within tumor tissues, represent an emerging and intriguing field in cancer biology. These microbial populations are distinct from the well-studied gut microbiota, offering novel insights into tumor biology, cancer progression, and potential therapeutic interventions. Recent studies have explored the use of certain antibiotics to modulate intratumoral microbiota and enhance the efficacy of cancer therapies, showing promising results. Antibiotics can alter intratumoral microbiota's composition, which may have a major role in promoting cancer progression and immune evasion. Certain bacteria within tumors can promote immunosuppression and resistance to therapies. By targeting these bacteria, antibiotics can help create a more favorable environment for chemotherapy, targeted therapy, and immunotherapy to act effectively. Some bacteria within the tumor microenvironment produce immunosuppressive molecules that inhibit the activity of immune cells. The combination of antibiotics and other cancer therapies holds significant promise for creating a synergistic effect and enhancing the immune response against cancer. In this review, we analyze several preclinical studies that have been conducted to demonstrate the synergy between antibiotics and other cancer therapies and discuss possible clinical implications.

In Silico Evaluation of Some Computer-Designed Fluoroquinolone-Glutamic Acid Hybrids as Potential Topoisomerase II Inhibitors with Anti-Cancer Effect

Background/Objectives: Fluoroquinolones (FQs) are topoisomerase II inhibitors with antibacterial activity, repositioned recently as anti-cancer agents. Glutamic acid (GLA) is an amino acid that affects human metabolism. Since an anti-cancer mechanism of FQs is human topoisomerase II inhibition, it is expected that FQ-GLA hybrids can act similarly. Methods: We designed 27 hypothetical hybrids of 6 FQs and GLA through amide bonds at the 3- and 7-position groups of FQs or via ethylenediamine/ethanolamine linkers at the carboxyl group of the FQ. Hydroxamic acid derivatives were also theoretically formulated. Computational methods were used to predict their physicochemical, pharmacokinetic, or toxicological properties and their anti-cancer activity. For comparison, etoposide was used as an anti-cancer agent inhibiting topoisomerase II. Molecular docking assessed whether the hybrids could interact with the human topoisomerase II beta in the same binding site and interaction sites as etoposide. Results: All the hybrids acted as potential topoisomerase II inhibitors, demonstrating possible anti-cancer activity on several cancer cell lines. Among all the proposed hybrids, MF-7-GLA would be the ideal candidate as a lead compound. The hybrid OF-3-EDA-GLA and the hydroxamic acid derivatives also stood out. Conclusions: Both FQs and GLA have advantageous structures for obtaining hybrids with favourable properties. Improvements in the hybrids' structure could lead to promising results.

Drug repurposing of fluoroquinolones as anticancer agents in 2023

Drug developers are currently focusing on investigating alternative strategies, such as "drug repositioning", to address issues associated with productivity, regulatory obstacles, and the steadily rising cost of pharmaceuticals. Repositioning is the best strategy to stop searching for new drugs because it takes less time and money to investigate new indications for already approved or unsuccessful drugs. Although there are several potent Topo II inhibitors available on the market as important drugs used in the therapy of many types of cancer, more may be required in the future. The current inhibitors have drawbacks including acquired resistance and unfavorable side effects such as cardiotoxicity and subsequent malignancy. A substantial body of research documented the cytotoxic potential of experimental fluoroquinolones (FQs) on tumor cell lines and their remarkable efficacy against eukaryotic Topo II in addition to optimized physical and metabolic characteristics. The FQ scaffold has a unique ability to potentially resolve every major issue associated with traditional Topo II inhibitors while maintaining a highly desirable profile in crucial drug-likeness parameters; therefore, there is a significant chance that FQs will be repositioned as anticancer candidates. This review offers a summary of the most recent research on the anticancer potential of FQs that was published in 2023. Along with discussing structural activity relationship studies and the mechanism underlying their antiproliferative activity, this review aims to provide up-to-date information that will spur the development of more potent FQs as viable cancer treatment candidates.

Unveiling the Anticancer Potential of a New Ciprofloxacin-Chalcone Hybrid as an Inhibitor of Topoisomerases I & II and Apoptotic Inducer

The current study has yielded promising results in the evaluation of a new ciprofloxacin-chalcone hybrid (CP derivative) for its anticancer activity as potential Topoisomerases (Topo) I and II inhibitors. The in vitro results showed that the CP derivative significantly suppressed the growth of HCT-116 and LOX IMVI cells, with IC50 values of 5.0 μM and 1.3 μM, respectively, outperforming Staurosporine, which had IC50 values of 8.4 μM and 1.6 μM, respectively. Flow cytometry analysis revealed that the new CP derivative triggered apoptosis and cell cycle arrest at the G2/M phase, associated with the up-regulation of pro-apoptotic genes (Bax and Caspase 9) and downregulation of the anti-apoptotic gene (Bcl-2). Further investigations showed that the CP derivative inhibited Topo I and II enzymes, as expected molecular targets; docking studies further supported its dual inhibitory action on Topo I and II. These findings suggest that the ciprofloxacin-chalcone hybrid could be a promising lead compound for developing new anticancer therapy.

Modulation of Long Non-coding RNA FAS-AS1/FAS/Caspase3 Axis in Endometriosis: A Cross-sectional Study

Background

An increasing number of studies have demonstrated that excessive proliferation and apoptosis play a pivotal role in the development of endometriosis.

Aim

The aim of the study was to evaluate the expression of long non-coding RNA (lncRNA) FAS-AS1, FAS, soluble Fas (sFas) and caspase-3 in patients with different stages of endometriosis.

Setting and Design

The design of the study was a cross-sectional study.

Materials and Methods

The relative expression of lncRNA FAS-AS1 and FAs gene was evaluated by the quantitative real-time polymerase chain reaction in 60 ectopic endometrial samples from women with endometriosis in relation to 85 normal endometrial tissues from healthy women, whereas the protein level of sFAs in the peritoneal fluid samples and cleaved caspase-3 in ectopic and normal endometrial tissue samples were determined using the enzyme-linked immunosorbent assay and western blot, respectively. Furthermore, in silico analyses were performed to investigate protein-protein interactions as well as molecular function and cellular location of selected proteins.

Statistical Analysis Used

The student's t-test was used to analyse the difference between the means of the two groups.

Results

The expression of FAS and sFas increased in endometriosis tissues as compared to the control group (P < 0.05). However, lncRNA FAS-AS1 and cleaved caspase-3 decreased in ectopic endometrial tissues compared to normal endometrial tissues and low lncRNA FAS-AS1 expression was correlated with disease stages. In addition, the in silico analysis revealed the importance of FAS/caspase3 in the biological processes involved in the development of endometriosis.

Conclusion

The current study suggests that lncRNA FAS-AS1 may function as an ectopic endometriotic suppressor. Moreover, the results showed that severity of endometriosis is also closely correlated with the expression of lncRNA FAS-AS1 and sFAS.

Ciprofloxacin Accelerates Angiotensin-II-Induced Vascular Smooth Muscle Cells Senescence Through Modulating AMPK/ROS pathway in Aortic Aneurysm and Dissection

Aortic aneurysm and dissection (AAD) is a cardiovascular disease that poses a severe threat to life and has high morbidity and mortality rates. Clinical and animal-based studies have irrefutably shown that fluoroquinolones, a commonly prescribed antibiotic for treating infections, significantly increase the risk of AAD. Despite this, the precise mechanism by which fluoroquinolones cause AAD remains unclear. Therefore, this study aims to investigate the molecular mechanism and role of Ciprofloxacin definitively-a type of fluoroquinolone antibiotic-in the progression of AAD. Aortic transcriptome data were collected from GEO datasets to detect the genes and pathways expressed differently between healthy donors and AAD patients. Human primary Vascular Smooth Muscle Cells (VSMCs) were isolated from the aorta. After 72 h of exposure to 110ug/ml Ciprofloxacin or 100 nmol/L AngII, either or combined, the senescent cells were identified through SA-β-gal staining. MitoTracker staining was used to examine the morphology of mitochondria in each group. Cellular Reactive Oxygen Species (ROS) levels were measured using MitoSox and DCFH-DA staining. Western blot assay was performed to detect the protein expression level. We conducted an analysis of transcriptome data from both healthy donors and patients with AAD and found that there were significant changes in cellular senescence-related signaling pathways in the latter group. We then isolated and identified human primary VSMCs from healthy donors (control-VSMCs) and patients' (AAD-VSMCs) aortic tissue, respectively. We found that VSMCs from patients exhibited senescent phenotype as compared to control-VSMCs. The higher levels of p21 and p16 and elevated SA-β-gal activity demonstrated this. We also found that pretreatment with Ciprofloxacin promoted angiotensin-II-induced cellular senescence in control-VSMCs. This was evidenced by increased SA-β-gal activity, decreased cell proliferation, and elevation of p21 and p16 protein levels. Additionally, we found that Angiotensin-II (AngII) induced VSMC senescence by promoting ROS generation. We used DCFH-DA and mitoSOX staining to identify that Ciprofloxacin and AngII pretreatment further elevated ROS levels than the vehicle or alone group. Furthermore, JC-1 staining showed that mitochondrial membrane potential significantly declined in the Ciprofloxacin and AngII combination group compared to others. Compared to the other three groups, pretreatment of Ciprofloxacin plus AngII could further induce mitochondrial fission, demonstrated by mitoTracker staining and western blotting assay. Mechanistically, we found that Ciprofloxacin impaired the balance of mitochondrial fission and fusion dynamics in VSMCs by suppressing the phosphorylation of AMPK signaling. This caused mitochondrial dysfunction and ROS generation, thereby elevating AngII-induced cellular senescence. However, treatment with the AMPK activator partially alleviated those effects. Our data indicate that Ciprofloxacin may accelerate AngII-induced VSMC senescence through modulating AMPK/ROS signaling and, subsequently, hasten the progression of AAD.

Licochalcone D exhibits cytotoxicity in breast cancer cells and enhances tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis through upregulation of death receptor 5

Anticancer strategies using natural products or derivatives are promising alternatives for cancer treatment. Here, we showed that licochalcone D (LCD), a natural flavonoid extracted from Glycyrrhiza uralensis Fisch, suppressed the growth of breast cancer cells, and was less toxic to MCF-10A normal breast cells. LCD-induced DNA damage, cell cycle arrest, and apoptosis in breast cancer cells. Furthermore, LCD potentiated tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced cytotoxicity. Mechanistically, LCD was revealed to reduce survival protein expression and to upregulate death receptor 5 (DR5) expressions. Silencing DR5 blocked the ability of LCD to sensitize cells to TRAIL-mediated apoptosis. LCD increased CCAAT/enhancer-binding protein homologous protein (CHOP) expression in breast cancer cells. Knockdown of CHOP attenuated DR5 upregulation and apoptosis triggered by cotreatment with LCD and TRAIL. Furthermore, LCD suppressed the phosphorylation of extracellular signal-regulated kinase and promoted the phosphorylation of c-Jun amino-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). Pretreatment with JNK inhibitor SP600125 or p38 MAPK inhibitor SB203580 abolished the upregulation of DR5 and CHOP, and also attenuated LCD plus TRAIL-induced cleavage of poly(ADP-ribose) polymerase. Overall, our results show that LCD exerts cytotoxic effects on breast cancer cells and arguments TRAIL-mediated apoptosis by inhibiting survival protein expression and upregulating DR5 in a JNK/p38 MAPK-CHOP-dependent manner.

Antibiotic use during radical surgery in stage I-III colorectal cancer: correlation with outcomes?

AIMS

Accumulating evidence indicates that the use of antibiotics (ATBs) in cancer patients is potentially correlated with patient prognosis. Interestingly, the use of these agents is not uncommon in colorectal cancer (CRC) patients during surgery; however, their prognostic value in the clinic has never been addressed.

MATERIALS AND METHODS

Data on ATB use during surgery, including the cumulative defined daily dose (cDDD) and the number of categories, were collected. Differences in the clinical data between the low and high cDDD subgroups and between subgroups with ≤ 4 and >4 categories. Additionally, the disease-free survival (DFS) and overall survival (OS) among these subgroups and the specific categories were compared. Finally, a Cox proportional hazard model was used to validate the risk factors for the outcome.

RESULTS

The number of categories, rather than the cDDD, was a significant predictor of both DFS (P = 0.043) and OS (P = 0.039). Patients with obstruction are more likely to have a high cDDD, whereas older patients are more likely to have multiple categories. There were no significant differences in the DFS (log rank = 1.36, P = 0.244) or OS (log rank = 0.40, P = 0.528) between patients in the low- and high-cDDD subgroups, whereas patients with ≤ 4 categories had superior DFS (log rank = 9.92, P = 0.002) and OS (log rank = 8.30, P = 0.004) compared with those with >4 categories. Specifically, the use of quinolones was harmful to survival (DFS: log rank = 3.67, P = 0.055; OS: log rank = 5.10, P = 0.024), whereas the use of macrolides was beneficial to survival (DFS: log rank = 12.26, P < 0.001; OS: log rank = 9.77, P = 0.002). Finally, the number of categories was identified as an independent risk factor for both DFS (HR = 2.05, 95% CI: 1.35-3.11, P = 0.001) and OS (HR = 1.82, 95% CI: 1.14-2.90, P = 0.012).

CONCLUSIONS

The cDDD of ATBs during surgery in stage I-III CRC patients did not correlate with outcome; however, patients in multiple categories or a specific category are likely to have inferior survival. These results suggest that particular caution should be taken when selecting ATBs for these patients in the clinic.

Differences in nature killer cell response and interference with mitochondrial DNA induced apoptosis in moxifloxacin environment

OBJECTIVES

As antibiotics become more prevalent, accuracy and safety are critical. Moxifloxacin (MXF) have been reported to have immunomodulatory effects on a variety of immune cells and even anti-proliferative and pro-apoptotic effects, but the mechanism of action is not fully clear.

METHODS

Peripheral blood mononuclear cells (PBMC) from experimental groups of healthy adults (n = 3) were treated with MXF (10ug/ml) in vitro for 24 h. Single-cell sequencing was performed to investigate differences in the response of each immune cell to MXF. Flow cytometry determined differential gene expression in subsets of most damaged NK cells. Pseudo-time analysis identified drivers that influence MXF-stimulated cell differentiation. Detection of mitochondrial DNA and its involvement in the mitochondrial respiratory chain pathway clarifies the origin of MXF-induced stress injury.

RESULTS

Moxifloxacin-environmental NK cells are markedly reduced: a new subset of NK cells emerges, and immediate-early-response genes in this subset indicate the presence of an early activation response. The inhibitory receptor-dominant subset shows enhanced activation, leading to increased expression of cytokines and chemokines. The near-mature subset showed greater cytotoxicity and the most pronounced cellular damage. CD56bright cells responded by antagonizing the regulation of activation and inhibitory signals, demonstrating a strong cleavage capacity. The severe depletion of mitochondrial genes was focused on apoptosis induced by the mitochondrial respiratory chain complex.

CONCLUSION

NK cells exhibit heightened sensitivity to the MXF environment. Different NK subsets upregulate the expression of cytokines and chemokines through different activation pathways. Concurrently, MXF induces impairment of the mitochondrial oxidative phosphorylation system, culminating in apoptosis.

Modulatory effect of ciprofloxacin, a broad spectrum antibacterial drug, on mPT pore using rat model with estradiol benzoate-induced endometrial hyperplasia

Mitochondrial permeability transition (mPT) pore has become a motive for drug evolvement pertinent to dysregulated apoptosis situations. Some chemical compounds impede tumor/cancer via the inception of mPT pore opening. Ciprofloxacin has been demonstrated to hinder growth and effect apoptosis in some cancer cells. However, using a rat model, this study investigated its effect on mitochondrial-mediated cell death via mPT pore opening and estradiol benzoate (EB)-induced endometrial hyperplasia. Mitochondria were isolated using differential centrifugation. The opening of the pore, cytochrome c release (CCR), mitochondrial ATPase (mATPase) activity, mitochondrial lipid peroxidation (mLPO), caspases 3 and 9 levels, and hepatic DNA fragmentation were determined. Histological evaluation of hepatic and uterine sections and immunoexpression levels of Bax, caspase 3, and anti-apoptotic Bcl-2 levels were quantified. The results show that ciprofloxacin caused mPT pore opening, CCR, mATPase activity, effected mLPO, caspases 3 and 9 activations, and hepatic DNA fragmentation. The histology of the liver section showed moderate to marked disseminated congestion at 100 mg/kg, while higher doses showed severe hepatic damage. Severe EH was detected in the EB-treated rats which was attenuated by ciprofloxacin in the treatment group. The Bax and caspase expressions were upregulated by ciprofloxacin while anti-apoptotic Bcl-2 was downregulated. Ciprofloxacin induces mitochondrial-mediated cell death via mPT pore opening and mitigates EB-induced EH in rat models via Bax/caspase/Bcl-2 signaling pathway.

Overcoming Microbiome-Acquired Gemcitabine Resistance in Pancreatic Ductal Adenocarcinoma

Gastrointestinal cancers (GICs) are one of the most recurrent diseases in the world. Among all GICs, pancreatic cancer (PC) is one of the deadliest and continues to disrupt people's lives worldwide. The most frequent pancreatic cancer type is pancreatic ductal adenocarcinoma (PDAC), representing 90 to 95% of all pancreatic malignancies. PC is one of the cancers with the worst prognoses due to its non-specific symptoms that lead to a late diagnosis, but also due to the high resistance it develops to anticancer drugs. Gemcitabine is a standard treatment option for PDAC, however, resistance to this anticancer drug develops very fast. The microbiome was recently classified as a cancer hallmark and has emerged in several studies detailing how it promotes drug resistance. However, this area of study still has seen very little development, and more answers will help in developing personalized medicine. PC is one of the cancers with the highest mortality rates; therefore, it is crucial to explore how the microbiome may mold the response to reference drugs used in PDAC, such as gemcitabine. In this article, we provide a review of what has already been investigated regarding the impact that the microbiome has on the development of PDAC in terms of its effect on the gemcitabine pathway, which may influence the response to gemcitabine. Therapeutic advances in this type of GIC could bring innovative solutions and more effective therapeutic strategies for other types of GIC, such as colorectal cancer (CRC), due to its close relation with the microbiome.

Ciprofloxacin and Norfloxacin Hybrid Compounds: Potential Anticancer Agents

BACKGROUND

The concept of utilizing drug repurposing/repositioning in the development of hybrid molecules is an important strategy in drug discovery. Fluoroquinolones, a class of antibiotics, have been reported to exhibit anticancer activities. Although anticancer drug development is achieving some positive outcomes, there is still a need to develop new and effective anticancer drugs. Some limitations associated with most of the available anticancer drugs are drug resistance and toxicity, poor bio-distribution, poor solubility, and lack of specificity, thereby reducing their therapeutic outcomes.

OBJECTIVES

Fluoroquinolones, a known class of antibiotics, have been explored by hybridizing them with other pharmacophores and evaluating their anticancer activity in silico and in vitro. Hence, this review provides an update on new anticancer drugs containing fluoroquinolones moiety, Ciprofloxacin and Norfloxacin between 2020 and 2023, their structural relationship activity, and the future strategies to develop potent chemotherapeutic agents.

METHODS

Fluoroquinolones were mostly hybridized via the N-4 of the piperazine ring on position C-7 with known pharmacophores characterized, followed by biological studies to evaluate their anticancer activity.

RESULTS

The hybrid molecules displayed promising and interesting anticancer activities. Factors such as the nature of the linker, the presence of electron-withdrawing groups, nature, and position of the substituents influenced the anticancer activity of the synthesized compounds.

CONCLUSION

The hybrids were selective towards some cancer cells. However, further in vivo studies are needed to fully understand their mode of action.

Carvacrol-Fabricated Chitosan Nanoparticle Synergistic Potential with Topoisomerase Inhibitors on Breast and Cervical Cancer Cells

Breast and cervical cancers are the most common heterogeneous malignancies in women. Chemotherapy with conventional drug delivery systems having several limitations along with development of multidrug resistance compelled us to seek out targeted therapeutics. Nanoparticles are suitable substitutes to circumvent multidrug resistance for the targeted treatment of cancer. The current study was aimed to investigate the anticancer effect of carvacrol-loaded chitosan nanoparticles with topoisomerase inhibitors. The average size of carvacrol-loaded chitosan nanoparticles was found to be 80 nm with 24.7 mV ζ-potential, and maximum absorbance was observed at 275 nm. Among all drug combinations, the carvacrol nanoparticles with the doxorubicin combination group exerted greater dose-dependent growth inhibition of both MCF-7 and HeLa cells as compared to single carvacrol nanoparticles and doxorubicin. Combination index values of carvacrol nanoparticles and the doxorubicin combination group showed a strong synergistic effect as they were found to be between 0.2 and 0.4, 0.31 for MCF-7 and 0.34 for HeLa cells. The carvacrol nanoparticles in combination with doxorubicin on MCF-7 cells reduced the dose 16.32-fold for carvacrol nanoparticles and 4.09-fold for doxorubicin at 6.23 μg/mL IC50, while on HeLa cells, this combination reduced the dose 13.18-fold for carvacrol nanoparticles and 3.83-fold for doxorubicin at 9.33 μg/mL IC50. As the dose reduction values were greater than 1, they indicated favorable dose reduction. It was concluded that the combination of carvacrol-loaded chitosan nanoparticles with topoisomerase inhibitors may represent an innovative and promising strategy to improve the efficacy, resistance, and targeted delivery of chemotherapeutics in cancer.

The tale of antibiotics beyond antimicrobials: Expanding horizons

Antibiotics had proved to be a godsend for mankind since their discovery. They were once the magical solution to the vexing problem of infection-related deaths. German scientist Paul Ehrlich had termed salvarsan as the silver bullet to treatsyphilis.As time passed, the magic of newly discovered silver bullets got tarnished with raging antibiotic resistance among bacteria and associated side-effects. Still, antibiotics remain the primary line of treatment for bacterial infections. Our understanding of their chemical and biological activities has increased immensely with advancement in the research field. Non-antibacterial effects of antibiotics are studied extensively to optimise their safer, broad-range use. These non-antibacterial effects could be both useful and harmful to us. Various researchers across the globe including our lab are studying the direct/indirect effects and molecular mechanisms behind these non-antibacterial effects of antibiotics. So, it is interesting for us to sum up the available literature. In this review, we have briefed the possible reason behind the non-antibacterial effects of antibiotics, owing to the endosymbiotic origin of host mitochondria. We further discuss the physiological and immunomodulatory effects of antibiotics. We then extend the review to discuss molecular mechanisms behind the plausible use of antibiotics as anticancer agents.

Effect of four fluoroquinolones on the viability of bladder cancer cells in 2D and 3D cultures

Introduction

The anticancer properties of fluoroquinolones and the high concentrations they achieve in urine may help in bladder cancer therapy. This study aimed to analyze the properties of 4 fluoroquinolones as potential candidates for supportive treatment of bladder cancer.

Methods

Comparative analyses were performed on the cytotoxic effects of norfloxacin, enrofloxacin, moxifloxacin, and ofloxacin on normal and cancer urothelial cell lines. In 2D culture, the cytotoxic properties of fluoroquinolones were evaluated using MTT assay, real-time cell growth analysis, fluorescence and light microscopy, flow cytometry, and molecular analysis. In 3D culture, the properties of fluoroquinolones were tested using luminescence assays and confocal microscopy.

Results and Discussion

All tested fluoroquinolones in 2D culture decreased the viability of both tested cell lines in a dose- and timedependent manner. Lower concentrations did not influence cell morphology and cytoskeletal organization. In higher concentrations, destruction of the actin cytoskeleton and shrinkage of the nucleus was visible. Flow cytometry analysis showed cell cycle inhibition of bladder cancer cell lines in the G2/M phase. This influence was minimal in the case of normal urothelium cells. In both tested cell lines, increases in the number of late apoptotic cells were observed. Molecular analysis showed variable expression of studied genes depending on the drug and concentration. In 3D culture, tested drugs were effective only in the highest tested concentrations which was accompanied by caspase 3/7 activation and cytoskeleton degradation. This effect was hardly visible in non-cancer cell lines. According to the data, norfloxacin and enrofloxacin had the most promising properties. These two fluoroquinolones exhibited the highest cytotoxic properties against both tested cell lines. In the case of norfloxacin, almost all calculated LC values for bladder cancer cell lines were achievable in the urine. Enrofloxacin and norfloxacin can be used to support chemotherapy in bladder cancer patients.

Characterization of LTr1 derived from cruciferous vegetables as a novel anti-glioma agent via inhibiting TrkA/PI3K/AKT pathway

Malignant glioma is the most fatal, invasive brain cancer with limited treatment options. Our previous studies show that 2-(indol-3-ylmethyl)-3,3'-diindolylmethane (LTr1), a major metabolite of indole-3-carbinol (I3C) derived from cruciferous vegetables, produces anti-tumour effect against various tumour cell lines. In this study we characterized LTr1 as a novel anti-glioma agent. Based on screening 134 natural compounds and comparing the candidates' efficacy and toxicity, LTr1 was selected as the lead compound. We showed that LTr1 potently inhibited the viability of human glioma cell lines (SHG-44, U87, and U251) with IC50 values of 1.97, 1.84, and 2.03 μM, respectively. Furthermore, administration of LTr1 (100,300 mg· kg-1 ·d-1, i.g. for 18 days) dose-dependently suppressed the tumour growth in a U87 xenograft nude mouse model. We demonstrated that LTr1 directly bound with TrkA to inhibit its kinase activity and the downstream PI3K/AKT pathway thus inducing significant S-phase cell cycle arrest and apoptosis in SHG-44 and U87 cells by activating the mitochondrial pathway and inducing the production of reactive oxygen species (ROS). Importantly, LTr1 could cross the blood-brain barrier to achieve the therapeutic concentration in the brain. Taken together, LTr1 is a safe and promising therapeutic agent against glioma through inhibiting TrkA/PI3K/AKT pathway.

N-Acylated Ciprofloxacin Derivatives: Synthesis and In Vitro Biological Evaluation as Antibacterial and Anticancer Agents

A novel series of N-acylated ciprofloxacin (CP) conjugates 1-21 were synthesized and screened as potential antimicrobial agents. Conjugates 1 and 2 were 1.25-10-fold more potent than CP toward all Staphylococci (minimal inhibitory concentration 0.05-0.4 μg/mL). Most of the chloro- (3-7), bromo- (8-11), and CF₃-alkanoyl (14-16) derivatives expressed higher or comparable activity to CP against selected Gram-positive strains. A few CP analogues (5, 10, and 11) were also more effective toward the chosen clinical Gram-negative rods. Conjugates 5, 10, and 11 considerably influenced the phases of the bacterial growth cycle over 18 h. Additionally, compounds 2, 4-7, 9-12, and 21 exerted stronger tuberculostatic action against three Mycobacterium tuberculosis isolates than the first-line antitubercular drugs. Amides 1, 2, 5, 6, 10, and 11 targeted gyrase and topoisomerase IV at 2.7-10.0 μg/mL, which suggests a mechanism of antibacterial action related to CP. These findings were confirmed by molecular docking studies. In addition, compounds 3 and 15 showed high antiproliferative activities against prostate PC3 cells (IC₅₀ 2.02-4.8 μM), up to 6.5-2.75 stronger than cisplatin. They almost completely reduced the growth and proliferation rates in these cells, without a cytotoxic action against normal HaCaT cell lines. Furthermore, derivatives 3 and 21 induced apoptosis/necrosis in PC3 cells, probably by increasing the intracellular ROS amount, as well as they diminished the IL-6 level in tumor cells.

Design and synthesis of novel cytotoxic fluoroquinolone analogs through topoisomerase inhibition, cell cycle arrest, and apoptosis

To exploit the advantageous properties of approved drugs to hasten anticancer drug discovery, we designed and synthesized a series of fluoroquinolone (FQ) analogs via functionalization of the acid hydrazides of moxifloxacin, ofloxacin, and ciprofloxacin. Under the NCI-60 Human Tumor Cell Line Screening Assay, (IIIf) was the most potent among moxifloxacin derivatives, whereas (VIb) was the only ofloxacin derivative with significant effects and ciprofloxacin derivatives were devoid of activity. (IIIf) and (VIb) were further selected for five-dose evaluation, where they showed potent growth inhibition with a mean GI₅₀ of 1.78 and 1.45 µM, respectively. (VIb) elicited a more potent effect reaching sub-micromolar level on many cell lines, including MDA-MB-468 and MCF-7 breast cancer cell lines (GI₅₀ = 0.41 and 0.42 µM, respectively), NSCLC cell line HOP-92 (GI₅₀ = 0.50 µM) and CNS cell lines SNB-19 and U-251 (GI₅₀ = 0.51 and 0.61 µM, respectively). (IIIf) and (VIb) arrested MCF-7 cells at G1/S and G1, respectively, and induced apoptosis mainly through the intrinsic pathway as shown by the increased ratio of Bax/Bcl-2 and caspase-9 with a lesser activation of the extrinsic pathway through caspase-8. Both compounds inhibited topoisomerase (Topo) with preferential activity on type II over type I and (VIb) was marginally more potent than (IIIf). Docking study suggests that (IIIf) and (VIb) bind differently to Topo II compared to etoposide. (IIIf) and (VIb) possess high potential for oral absorption, low CNS permeability and low binding to plasma proteins as suggested by in silico ADME calculations. Collectively, (IIIf) and (VIb) represent excellent lead molecules for the development of cytotoxic agents from quinolone scaffolds.

Anticancer activity and metabolic alteration in colon and prostate cancer cells by novel moxifloxacin conjugates with fatty acids

The positive and pro-economic trend in the management of cancer treatment is the search for the antineoplastic potential of known, widely used and safe drugs with a different clinical purpose. A good candidate seems to be moxifloxacin with broad-spectrum antibacterial activity, which as the member of the fourth generation fluoroquinolone is known to affect not only bacterial but also eukaryotic DNA topoisomerases, however at high concentration. Due to the fact that the modification of parent drug with lipid component can improve anticancer potential by increasing of bioavailability, selectivity, and cytotoxic efficiency, we evaluated the mechanisms of cytotoxic activity of novel moxifloxacin conjugates with fatty acids and verified metabolic profile in SW480, SW620 and PC3 cell lines. Our study revealed that cytotoxic potential of moxifloxacin conjugates was stronger than free moxifloxacin, moreover, they remained non-toxic to normal HaCaT cells. PC3 were more sensitive to MXF conjugates than colon cancer cells. The most promising cytotoxic activity exhibited conjugate 4m and 16m with oleic and stearic acid reducing viability of PC3 and SW620 cells. Tested conjugates activated caspases 3/7 and induced late-apoptosis, mainly in PC3 and SW620 cells. However, the most pronounced inhibition of NF-κB activation and IL-6 secretion was observed in SW480. Metabolomic analysis indicated influence of the moxifloxacin conjugates on intensity of lipid derivatives with the most successful metabolite profile in PC3. Our findings suggested the cytotoxic potential of moxifloxacin conjugates, especially with oleic and stearic acid can be beneficial in oncological therapy, including their possible anti-inflammatory and known antibacterial effect.

Ciprofloxacin exacerbates dysfunction of smooth muscle cells in a microphysiological model of thoracic aortic aneurysm

Ciprofloxacin use may be associated with adverse aortic events. However, the mechanism underlying the effect of ciprofloxacin on the progression of thoracic aortic aneurysm (TAA) is not well understood. Using an in vitro microphysiological model, we treated human aortic smooth muscle cells (HASMCs) derived from patients with bicuspid aortic valve- or tricuspid aortic valve-associated (BAV- or TAV-associated) TAAs with ciprofloxacin. TAA C57BL/6 mouse models were utilized to verify the effects of ciprofloxacin exposure. In the microphysiological model, real-time PCR, Western blotting, and RNA sequencing showed that ciprofloxacin exposure was associated with a downregulated contractile phenotype, an upregulated inflammatory reaction, and extracellular matrix (ECM) degradation in the normal HASMCs derived from the nondiseased aorta. Ciprofloxacin induced mitochondrial dysfunction in the HASMCs and further increased apoptosis by activating the ERK1/2 and P38 mitogen-activated protein kinase pathways. These adverse effects appeared to be more severe in the HASMCs derived from BAV- and TAV-associated TAAs than in the normal HASMCs when the ciprofloxacin concentration exceeded 100 μg/mL. In the aortic walls of the TAA-induced mice, ECM degradation and apoptosis were aggravated after ciprofloxacin exposure. Therefore, ciprofloxacin should be used with caution in patients with BAV- or TAV-associated TAAs.

In Vitro Anticancer Activity of Novel Ciprofloxacin Mannich Base in Lung Adenocarcinoma and High-Grade Serous Ovarian Cancer Cell Lines via Attenuating MAPK Signaling Pathway

Novel drugs are desperately needed in order to combat a significant challenge due to chemo-therapeutic resistance and bad prognosis. This research aimed to assess the anticancer activity of a newly synthesized ciprofloxacin Mannich base (CMB) on ovarian cancer (OVCAR-3) and lung cancer (A-549) cell lines and to investigate probable involved molecular mechanisms. The cytotoxic and pro-apoptotic impact of CMB on both cell lines was investigated using MTT assay, Annexin V assay, and cell cycle analysis, as well as caspase-3 activation. Western blotting was carried out to evaluate downstream targets of the MAPK pathway, while qRT PCR was used to evaluate the gene expression pattern of the p53/Bax/Bcl2 pathway. CMB treatment showed significantly reduced cell proliferation in both OVCAR-3 and A-549 cells with half maximum inhibitory concentration (IC₅₀) = 11.60 and 16.22 µg/mL, respectively. CMB also induced apoptosis, S phase cell cycle arrest, and up-regulated expression of p53, p21, and Bax while down-regulated Bcl2 expression. CMB also halted cell proliferation by deactivating the MAPK pathway. In conclusion, CMB may be regarded as a potential antiproliferative agent for lung and ovarian cancers due to anti-proliferative and pro-apoptotic actions via inhibition of the MAPK pathway and p53/Bax/Bcl2.

Design, synthesis, and biological evaluation of novel ciprofloxacin derivatives as potential anticancer agents targeting topoisomerase II enzyme

A series of novel ciprofloxacin (CP) derivatives substituted at the N-4 position with biologically active moieties were designed and synthesised. 14 compounds were 1.02- to 8.66-fold more potent than doxorubicin against T-24 cancer cells. Ten compounds were 1.2- to 7.1-fold more potent than doxorubicin against PC-3 cancer cells. The most potent compounds 6, 7a, 7b, 8a, 9a, and 10c showed significant Topo II inhibitory activity (83-90% at 100 μM concentration). Compounds 6, 8a, and 10c were 1.01- to 2.32-fold more potent than doxorubicin. Compounds 6 and 8a induced apoptosis in T-24 (16.8- and 20.1-fold, respectively compared to control). This evidence was supported by an increase in the level of apoptotic caspase-3 (5.23- and 7.6-fold, sequentially). Both compounds arrested the cell cycle in the S phase in T-24 cancer cells while in PC-3 cancer cells the two compounds arrested the cell cycle in the G1 phase. Molecular docking simulations of compounds 6 and 8a into the Topo II active site rationalised their remarkable Topo II inhibitory activity.

Increased MARCKS Activity in BRAF Inhibitor-Resistant Melanoma Cells Is Essential for Their Enhanced Metastatic Behavior Independent of Elevated WNT5A and IL-6 Signaling

Treatment of melanoma with a BRAF inhibitor (BRAFi) frequently initiates development of BRAFi resistance, leading to increased tumor progression and metastasis. Previously, we showed that combined inhibition of elevated WNT5A and IL-6 signaling reduced the invasion and migration of BRAFi-resistant (BRAFi-R) melanoma cells. However, the use of a combined approach per se and the need for high inhibitor concentrations to achieve this effect indicate a need for an alternative and single target. One such target could be myristoylated alanine-rich C-kinase substrate (MARCKS), a downstream target of WNT5A in BRAFi-sensitive melanoma cells. Our results revealed that MARCKS protein expression and activity are significantly elevated in PLX4032 and PLX4720 BRAFi-R A375 and HTB63 melanoma cells. Surprisingly, neither WNT5A nor IL-6 contributed to the increases in MARCKS expression and activity in BRAFi-R melanoma cells, unlike in BRAFi-sensitive melanoma cells. However, despite the above findings, our functional validation experiments revealed that MARCKS is essential for the increased metastatic behavior of BRAFi-R melanoma cells. Knockdown of MARCKS in BRAFi-R melanoma cells caused reductions in the F-actin content and the number of filopodia-like protrusions, explaining the impaired migration, invasion and metastasis of these cells observed in vitro and in an in vivo zebrafish model. In our search for an alternative explanation for the increased activity of MARCKS in BRAFi-R melanoma cells, we found elevated basal activities of PKCα, PKCε, PKCι, and RhoA. Interestingly, combined inhibition of basal PKC and RhoA effectively impaired MARCKS activity in BRAFi-R melanoma cells. Our results reveal that MARCKS is an attractive single antimetastatic target in BRAFi-R melanoma cells.

RETRACTED: hsa-miR-23a~27a~24-2 cluster members inhibit aggressiveness of breast cancer cells by commonly targeting NCOA1, NLK and RAP1B

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. The corresponding author notified the journal of three examples of image duplication within the published article (two in Figure 3D and one in Figure 4A), and requested a corrigendum. As per journal policy when considering corrigendum requests, the journal requested the authors to provide source data relating to these affected figures. The editorial team noticed 12 additional suspected image duplications within the supplied source data and the corresponding author was informed. Upon submission of revised source data, the editorial team noticed two new suspected image duplications. The editorial team have concerns about the provenance of the data and therefore the Editor-in-Chief decided to retract the article.

Computational evidence based perspective on the plausible repositioning of fluoroquinolones for COVID-19 treatment

The coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has become a serious global healthcare crisis, so there is an emergence of identifying efficacious therapeutic options. In a setting where there is an unavailability of definitive medication along with the constant eruption of vaccine-related controversies, the drug-repositioning approach seems to be an ideal step for the management of COVID-19 patients. Fluoroquinolones (FQs) are commonly prescribed antibiotics for the treatment of genitourinary tract and upper respiratory tract infections, including severe community-acquired pneumonia. Research over the years has postulated multifaceted implications of FQs in various pathological conditions. Previously, it has been reported that few, but not all FQs, possess strong antiviral activity with an unknown mechanism of action. Herein, an interesting perspective is discussed on repositioning possibilities of FQs for the SARS-CoV-2 infections based on the recent in silico evidential support. Noteworthy, FQs possess immunomodulatory and bactericidal activity which could be valuable for patients dealing with COVID-19 related complications. Conclusively, the current perspective could pave the way to initiate pre-clinical testing of FQs against several strains of SARS-CoV-2.

Interaction between moxifloxacin and Mcl-1 and MITF proteins: the effect on growth inhibition and apoptosis in MDA-MB-231 human triple-negative breast cancer cells

Background

Microphthalmia-associated transcription factor (MITF) activates the expression of genes involved in cellular proliferation, DNA replication, and repair, whereas Mcl-1 is a member of the Bcl-2 family of proteins that promotes cell survival by preventing apoptosis. The objective of the present study was to verify whether the interaction between moxifloxacin (MFLX), one of the fluoroquinolones, and MITF/Mcl-1 protein, could affect the viability, proliferation, and apoptosis in human breast cancer using both in silico and in vitro models.

Methods

Molecular docking analysis (in silico), fluorescence image cytometry, and Western blot (in vitro) techniques were applied to assess the contribution of MITF and Mcl-1 proteins in the MFLX-induced anti-proliferative and pro-apoptotic effects on the MDA-MB-231 breast cancer cells.

Results

We indicated the ability of MFLX to form complexes with MITF and Mcl-1 as well as the drug’s capacity to affect the expression of the tested proteins. We also showed that MFLX decreased the viability and proliferation of MDA-MB-231 cells and induced apoptosis via the intrinsic death pathway. Moreover, the analysis of the cell cycle progression revealed that MFLX caused a block in the S and G2/M phases.

Conclusions

We demonstrated for the first time that the observed effects of MFLX on MDA-MB-231 breast cancer cells (growth inhibition and apoptosis induction) could be related to the drug’s ability to interact with MITF and Mcl-1 proteins. Furthermore, the presented results suggest that MITF and Mcl-1 proteins could be considered as the target in the therapy of breast cancer.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s43440-022-00407-7.

Drug repurposing: An emerging strategy in alleviating skin cancer

Skin cancer is one of the most common forms of cancer. Several million people are estimated to have affected with this condition worldwide. Skin cancer generally includes melanoma and non-melanoma with the former being the most dangerous. Chemotherapy has been one of the key therapeutic strategies employed in the treatment of skin cancer, especially in advanced stages of the disease. It could be also used as an adjuvant with other treatment modalities depending on the type of skin cancer. However, there are several shortfalls associated with the use of chemotherapy such as non-selectivity, tumour resistance, life-threatening toxicities, and the exorbitant cost of medicines. Furthermore, new drug discovery is a lengthy and costly process with minimal likelihood of success. Thus, drug repurposing (DR) has emerged as a new avenue where the drug approved formerly for the treatment of one disease can be used for the treatment of another disease like cancer. This approach is greatly beneficial over the de novo approach in terms of time and cost. Moreover, there is minimal risk of failure of repurposed therapeutics in clinical trials. There are a considerable number of studies that have reported on drugs repurposed for the treatment of skin cancer. Thus, the present manuscript offers a comprehensive overview of drugs that have been investigated as repurposing candidates for the efficient treatment of skin cancers mainly melanoma and its oncogenic subtypes, and non-melanoma. The prospects of repurposing phytochemicals against skin cancer are also discussed. Furthermore, repurposed drug delivery via topical route and repurposed drugs in clinical trials are briefed. Based on the findings from the reported studies discussed in this manuscript, drug repurposing emerges to be a promising approach and thus is expected to offer efficient treatment at a reasonable cost in devitalizing skin cancer.

Quinolones as a Potential Drug in Genitourinary Cancer Treatment-A Literature Review

Quinolones, broad-spectrum antibiotics, are frequently prescribed by urologists for many urological disorders. The mechanism of their bactericidal activity is based on the inhibition of topoisomerase II or IV complex with DNA, which consequently leads to cell death. It has been observed that these antibiotics also act against the analogous enzymes present in eukaryotic cells. Due to their higher accumulation in urine and prostate tissue than in serum, these drugs seem to be ideal candidates for application in genitourinary cancer treatment. In this study, an extensive literature review has been performed to collect information about concentrations achievable in urine and prostate tissue together with information about anticancer properties of 15 quinolones. Special attention was paid to the application of cytotoxic properties of quinolones for bladder and prostate cancer cell lines. Data available in the literature showed promising properties of quinolones, especially in the case of urinary bladder cancer treatment. In the case of prostate cancer, due to low concentrations of quinolones achievable in prostate tissue, combination therapy with other chemotherapeutics or another method of drug administration is necessary.

New 1,2,3-triazole linked ciprofloxacin-chalcones induce DNA damage by inhibiting human topoisomerase I& II and tubulin polymerization

A series of novel 1,2,3-triazole-linked ciprofloxacin-chalcones 4a-j were synthesised as potential anticancer agents. Hybrids 4a-j exhibited remarkable anti-proliferative activity against colon cancer cells. Compounds 4a-j displayed IC₅₀s ranged from 2.53-8.67 µM, 8.67-62.47 µM, and 4.19-24.37 µM for HCT116, HT29, and Caco-2 cells; respectively, whereas the doxorubicin, showed IC₅₀ values of 1.22, 0.88, and 4.15 µM. Compounds 4a, 4b, 4e, 4i, and 4j were the most potent against HCT116 with IC₅₀ values of 3.57, 4.81, 4.32, 4.87, and 2.53 µM, respectively, compared to doxorubicin (IC₅₀ = 1.22 µM). Also, hybrids 4a, 4b, 4e, 4i, and 4j exhibited remarkable inhibitory activities against topoisomerase I, II, and tubulin polymerisation. They increased the protein expression level of γH2AX, indicating DNA damage, and arrested HCT116 in G2/M phase, possibly through the ATR/CHK1/Cdc25C pathway. Thus, the novel ciprofloxacin hybrids could be exploited as potential leads for further investigation as novel anticancer medicines to fight colorectal carcinoma.

Ceftazidime and cefepime antagonize 5-fluorouracil's effect in colon cancer cells

Background

Drug-drug interaction (DDI), which can occur at the pharmacokinetics and/or the pharmacodynamics (PD) levels, can increase or decrease the therapeutic or adverse response of a drug itself or a combination of drugs. Cancer patients often receive, along their antineoplastic agents, antibiotics such as ß-lactams to treat or prevent infection. Despite the narrow therapeutic indices of antibiotics and antineoplastic agents, data about their potential interaction are insufficient. 5-fluorouracil (5-FU), widely used against colon cancer, is known for its toxicity and large intra- and inter- individual variability. Therefore, knowledge about its interaction with antibiotics is crucial.

Methods

In this study, we evaluated at the PD levels, against HCT-116 colon cancer cells, DDI between 5-FU and several ß-lactams (ampicillin, benzypenicillin, piperacillin, meropenem, flucloxacillin, ceftazidime (CFT), and cefepime (CFP)), widely used in intensive care units. All drugs were tested at clinically achieved concentrations. MTT assay was used to measure the metabolic activity of the cells. Cell cycle profile and apoptosis induction were monitored, in HCT-116 and DLD-1 cells, using propidium iodide staining and Caspase-3/7 activity assay. The uptake of CFT and CFP by the cells was measured using LC-MS/MS method.

Results

Our data indicate that despite their limited uptake by the cells, CFT and CFP (two cephalosporins) antagonized significantly 5-FU-induced S-phase arrest (DLD-1 cells) and apoptosis induction (HCT-116 cells). Remarkably, while CFP did not affect the proliferation of colon cancer cells, CFT inhibited, at clinically relevant concentrations, the proliferation of DLD-1 cells via apoptosis induction, as evidenced by an increase in caspase 3/7 activation. Unexpectedly, 5-FU also antagonized CFT’s induced cell death in DLD-1 cells.

Conclusion

This study shows that CFP and CFT have adverse effects on 5-FU’s action while CFT is a potent anticancer agent that inhibits DLD-1 cells by inducing apoptotic cell death. Further studies are needed to decipher the mechanism(s) responsible for CFT’s effects against colon cancer as well as the observed antagonism between CFT, CFP, and 5-FU with the ultimate aim of translating the findings to the clinical settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-09125-4.

Nitric Oxide Photo-Donor Hybrids of Ciprofloxacin and Norfloxacin: A Shift in Activity from Antimicrobial to Anticancer Agents

The potential anticancer effect of fluoroquinolone antibiotics has been recently unveiled and related to their ability to interfere with DNA topoisomerase II. We herein envisioned the design and synthesis of novel Ciprofloxacin and Norfloxacin nitric oxide (NO) photo-donor hybrids to explore the potential synergistic antitumor effect exerted by the fluoroquinolone scaffold and NO eventually produced upon light irradiation. Anticancer activity, evaluated on a panel of tumor cell lines, showed encouraging results with IC50 values in the low micromolar range. Some compounds displayed intense antiproliferative activity on triple-negative and doxorubicin-resistant breast cancer cell lines, paving the way for their potential use to treat aggressive, refractory and multidrug-resistant breast cancer. No significant additive effect was observed on PC3 and DU145 cells following NO release. Conversely, antimicrobial photodynamic experiments on both Gram-negative and Gram-positive microorganisms displayed a significant killing rate in Staphylococcus aureus, accounting for their potential effectiveness as selective antimicrobial photosensitizers.

In vitro inhibition and molecular docking of a new ciprofloxacin-chalcone against SARS-CoV-2 main protease

Background/Aim

SARS‐CoV‐2 is one of the coronavirus families that emerged at the end of 2019. It infected the respiratory system and caused a pandemic worldwide. Fluoroquinolones (FQs) have been safely used as antibacterial agents for decades. The antiviral activity of FQs was observed. Moreover, substitution on the C‐7 position of ciprofloxacin enhanced its antiviral activity. Therefore, this study aims to investigate the antiviral activity of 7‐(4‐(N‐substituted‐carbamoyl‐methyl)piperazin‐1yl)‐chalcone in comparison with ciprofloxacin against SARS‐CoV‐2 main protease (M^pro).

Materials and methods

Vero cells were infected with SARS‐CoV‐2. After treatment with ciprofloxacin and the chalcone at the concentrations of 1.6, 16, 160 nmol/L for 48 h, SARS‐CoV‐2 viral load was detected using real‐time qPCR, SARS‐CoV‐2 infectivity was determined using plaque assay, and the main protease enzyme activity was detected using in vitro 3CL‐protease inhibition assay. The activity of the chalcone was justified through molecular docking within SARS‐CoV‐2 M^pro, in comparison with ciprofloxacin.

Results

The new chalcone significantly inhibited viral load replication where the EC50 was 3.93 nmol/L, the plaque formation ability of the virus was inhibited to 86.8% ± 2.47. The chalcone exhibited a significant inhibitory effect against SARS‐CoV‐2 M^pro in vitro in a dose‐dependent manner. The docking study into SARS‐CoV‐2 M^pro active site justified the importance of adding a substitution to the parent drug. Additionally, the assessment of the drug‐likeness properties indicated that the chalcone might have acceptable ADMET properties.

Conclusion

The new chalcone might be useful and has new insights for the inhibition of SARS‐CoV‐2 M^pro.

Synergistic inhibitory effects of the oxyresveratrol and dacarbazine combination against melanoma cells

Various therapies have been developed to target malignant melanoma, which is associated with a high mortality rate worldwide. Although dacarbazine (DTIC) is employed for treating melanoma, it is associated with several side effects. Hence, patients with melanoma are co-treated with additional drugs to mitigate the side effects of DTIC. In the present study, synergistic therapeutic effects of the DTIC/oxyresveratrol (ORT) combination were examined using the human malignant melanoma WM-266-4 cell line. Treatment with ORT and DTIC inhibited the proliferation of WM-266-4 cells. Compared with those in the ORT- and DTIC-treated groups, the proportion of cells arrested at the S phase, as well as apoptotic rates, were increased in the ORT and DTIC co-treatment group. In WM-266-4 cells, synergistic proliferation-inhibitory activities of the ORT/DTIC combination were assessed based on cell viability and migration, antioxidant capacity, cytokine production, cell cycle arrest, apoptotic rate and protein expression through WST-1 assay, wound healing assay, flow cytometry and western blotting. Furthermore, the expression levels of proteins, including NOTCH, involved in the pathogenesis of solid cancers, such as melanoma, were examined. Overall, the ORT/DTIC combination synergistically promoted cell cycle arrest at the S phase and the apoptosis of WM-266-4 cells. Thus, this combination treatment may serve as a novel therapeutic strategy for treating malignant melanoma.

Antiproliferative properties of 7,8-Ethylene Diamine Chelator-Lipophilic Fluoroquinolone Derivatives Against colorectal cancer Cell Lines

BACKGROUND

Cancer is one of the most overwhelming diseases nowadays. It is considered the second cause of death after cardiovascular diseases. Due to the diversity of its types, stages, and genetic origin, there is no available drug to treat all cancers. Serious side effects and resistance to existing drugs are other problems in this struggle against cancer. In such quest, fluoroquinolones (FQs) offer a future promise as antiproliferative compounds due to safety, low cost, and lack of resistance.

OBJECTIVES

Therefore, this work aims at developing lipophilic FQs and screening their antiproliferative activity against colorectal cancer.

METHODS

Nine prepared FQs were investigated for antiproliferative activity utilizing in vitro SRB method. In comparison to the antiproliferative agent cisplatin, the assessment of antiproliferative activities of these novel FQs in a panel of colorectal cancer cell (crc) lines (HT29, HCT116, SW620, CACO2, SW480) and normal periodontal ligament fibroblasts for safety examination was performed. Antibacterial activity (MIC) was conducted against Staphylococcus aureus and Escherichia coli standard strains using the broth double dilution method. Antioxidant properties were suspected as the mechanism of antiproliferative activity; thus, a DPPH test was performed to analyze the radical scavenging potency of FQs compared to ascorbic acid as a reference agent. FQs compounds 3-5(a-c) were prepared, characterized and their structure was confirmed using spectroscopy techniques.

RESULTS

All compounds manifested good to excellent antiproliferative activity on HT29, HCT116, and SW620 with high safety index. The reduced series 4a, 4b, and 4c exerted excellent micro to nanomolar antiproliferative activities on HT29, HCT116, and SW620, which were stronger than the reference cisplatin against all cells. The reduced group of compounds 4(a-c) revealed higher potency vs. both nitro and triazolo groups. On cell lines HT29, HCT116, and SW620 reduced 4a with 7,8-ethylene diamine substitution revealed the highest antiproliferative efficacy (IC50 value) approaching nanomolar affinity with higher safety vs. cisplatin. The most active compound, 4a, exhibited significant potency against HCT116 and SW620 with IC50 0.6 and 0.16 µM, respectively. Novel FQs (4a, 4b, and 4c) also showed strong radical scavenging activity with IC50 values (µM) 0.06, 23, and 7.99, respectively. Exquisitely 4a revealed a similar pattern of activity to doxorubicin, indicating a similar mechanism of action. Strong antiproliferative and weak antibacterial activities of series 4 endorse that their mechanism involves eukaryotic topoisomerase II inhibition. This work has revealed novel FQs with excellent anticancer activity against 5 colorectal cancer (HT29, HCT116, SW620, CACO2, SW480) cell lines with a potential chelation mechanism due to 7,8-ethylene diamine chelator bridge.

CONCLUSIONS

The new FQs have confirmed that more lipophilic compounds could be more active as hypothesized. The p-halogenated aniline, N1-Butyl group in addition to 3-COOH, 8-NH2 are all essential requirements for strong antiproliferative FQ of our FQ scaffold. This work emphasizes the role of C-8 amino as part of ethylene diamine group as an essential requirement for antiproliferative FQs for the first time in the literature, entailing its role toward potential antneoplastic FQs.

Selective toxicity of antibacterial agents-still a valid concept or do we miss chances and ignore risks?

BACKGROUND

Selective toxicity antibacteribiotics is considered to be due to interactions with targets either being unique to bacteria or being characterized by a dichotomy between pro- and eukaryotic pathways with high affinities of agents to bacterial- rather than eukaryotic targets. However, the theory of selective toxicity oversimplifies the complex modes of action of antibiotics in pro- and eukaryotes.

METHODS AND OBJECTIVE

This review summarizes data describing multiple modes of action of antibiotics in eukaryotes.

RESULTS

Aminoglycosides, macrolides, oxazolidinones, chloramphenicol, clindamycin, tetracyclines, glycylcyclines, fluoroquinolones, rifampicin, bedaquillin, ß-lactams inhibited mitochondrial translation either due to binding to mitosomes, inhibition of mitochondrial RNA-polymerase-, topoisomerase 2ß-, ATP-synthesis, transporter activities. Oxazolidinones, tetracyclines, vancomycin, ß-lactams, bacitracin, isoniazid, nitroxoline inhibited matrix-metalloproteinases (MMP) due to chelation with zinc and calcium, whereas fluoroquinols fluoroquinolones and chloramphenicol chelated with these cations, too, but increased MMP activities. MMP-inhibition supported clinical efficacies of ß-lactams and daptomycin in skin-infections, and of macrolides, tetracyclines in respiratory-diseases. Chelation may have contributed to neuroprotection by ß-lactams and fluoroquinolones. Aminoglycosides, macrolides, chloramphenicol, oxazolidins oxazolidinones, tetracyclines caused read-through of premature stop codons. Several additional targets for antibiotics in human cells have been identified like interaction of fluoroquinolones with DNA damage repair in eukaryotes, or inhibition of mucin overproduction by oxazolidinones.

CONCLUSION

The effects of antibiotics on eukaryotes are due to identical mechanisms as their antibacterial activities because of structural and functional homologies of pro- and eukaryotic targets, so that the effects of antibiotics on mammals are integral parts of their overall mechanisms of action.

Down-regulation of Survivin and Bcl-2 concomitant with the activation of caspase-3 as a mechanism of apoptotic death in KG1a and K562 cells upon exposure to a derivative from ciprofloxacin family

Ciprofloxacin derivatives belong to a family of antibiotics called fluoroquinolones. Recently, these compounds have been recommended for the treatment of cancer. In the present study, we assessed the cytotoxicity of several new synthetic ciprofloxacin derivatives and the apoptosis-inducing activity of the most efficient derivative in two human myeloid leukemia K562 and KG1-a cell lines. Among the prepared ciprofloxacin derivatives, 1-cyclopropyl-7-(4-(2-((3,7-dimethyloct-6-en-1-yl)oxy)-2-oxoethyl)piperazin-1-yl)-6-fluoro-4-oxo-1,4dihydroquinoline-3-carboxylic acid (4-DMOCP) was more active compound with IC50 of 19.56 and 22.13 μM for K562 and KG1-a, respectively. Apoptotic activity of the 4-DMOCP was examined morphologically through Hoechst 33258 staining, Annexin V/PI double staining, and caspase-3 activity assays. Changes in the expression level of some apoptosis-related genes and protein, including Bcl-2, Bax, Survivin, p53, Caspase-8 and Caspase-9 were evaluated by the real-time quantitative PCR (qRT PCR) and western blotting. The qRT PCR analysis showed that 4-DMOCP induces apoptosis in both cell lines via the down-regulation of Survivin and Bcl2, up-regulation of caspase-8 and -9, as well as a time-dependent increase in the Bax/Bcl2 transcripts. The mRNA level of p53 was also increased in both cell lines. In addition, western blot analysis revealed that treatment with the compound, down-regulated the protein expression levels of Bcl2 and Survivin and up-regulated the protein level of Bax in both cell lines. These findings suggest that these new compounds can be good candidates for the treatment of acute and chronic myeloid leukemia.

Novel urea linked ciprofloxacin-chalcone hybrids having antiproliferative topoisomerases I/II inhibitory activities and caspases-mediated apoptosis

A novel series of urea-linked ciprofloxacin (CP)-chalcone hybrids 3a-j were synthesized and screened by NCI-60 cancer cell lines as potential cytotoxic agents. Interestingly, compounds 3c and 3j showed remarkable antiproliferative activities against both colon HCT-116 and leukemia SR cancer cells compared to camptothecin, topotecan and staurosporine with IC₅₀ = 2.53, 2.01, 17.36, 12.23 and 3.1 μM for HCT-116 cells, respectively and IC₅₀ = 0.73, 0.64, 3.32, 13.72 and 1.17 μM for leukemia SR cells, respectively. Also, compounds 3c and 3j exhibited inhibitory activities against Topoisomerase (Topo) I with % inhibition = 51.19% and 56.72%, respectively, compared to camptothecin (% inhibition = 60.05%) and Topo IIβ with % inhibition = 60.81% and 60.06%, respectively, compared to topotecan (% inhibition = 71.09%). Furthermore, compound 3j arrested the cell cycle of leukemia SR cells at G2/M phase. It induced apoptosis both intrinsically and extrinsically via activation of proteolytic caspases cascade (caspases-3, -8, and -9), release of cytochrome C from mitochondria, upregulation of proapoptotic Bax and down-regulation of Bcl-2 protein level. Thus, the new ciprofloxacin derivative 3j could be considered as a potential lead for further optimization of antitumor agent against leukemia and colorectal carcinoma.

Uncovering New Drug Properties in Target-Based Drug-Drug Similarity Networks

Despite recent advances in bioinformatics, systems biology, and machine learning, the accurate prediction of drug properties remains an open problem. Indeed, because the biological environment is a complex system, the traditional approach—based on knowledge about the chemical structures—can not fully explain the nature of interactions between drugs and biological targets. Consequently, in this paper, we propose an unsupervised machine learning approach that uses the information we know about drug–target interactions to infer drug properties. To this end, we define drug similarity based on drug–target interactions and build a weighted Drug–Drug Similarity Network according to the drug–drug similarity relationships. Using an energy-model network layout, we generate drug communities associated with specific, dominant drug properties. DrugBank confirms the properties of 59.52% of the drugs in these communities, and 26.98% are existing drug repositioning hints we reconstruct with our DDSN approach. The remaining 13.49% of the drugs seem not to match the dominant pharmacologic property; thus, we consider them potential drug repurposing hints. The resources required to test all these repurposing hints are considerable. Therefore we introduce a mechanism of prioritization based on the betweenness/degree node centrality. Using betweenness/degree as an indicator of drug repurposing potential, we select Azelaic acid and Meprobamate as a possible antineoplastic and antifungal, respectively. Finally, we use a test procedure based on molecular docking to analyze Azelaic acid and Meprobamate’s repurposing.

Molecular Screening for Nigericin Treatment in Pancreatic Cancer by High-Throughput RNA Sequencing

Objectives: Nigericin, an antibiotic derived from Streptomyces hygroscopicus, has been proved to exhibit promising anti-cancer effects on a variety of cancers. Our previous study investigated the potential anti-cancer properties in pancreatic cancer (PC), and demonstrated that nigericin could inhibit the cell viabilities in concentration- and time-dependent manners via differentially expressed circular RNAs (circRNAs). However, the knowledge of nigericin associated with long non-coding RNA (lncRNA) and mRNA in pancreatic cancer (PC) has not been studied. This study is to elucidate the underlying mechanism from the perspective of lncRNA and mRNA.

Methods: The continuously varying molecules (lncRNAs and mRNAs) were comprehensively screened by high-throughput RNA sequencing.

Results: Our data showed that 76 lncRNAs and 172 mRNAs were common differentially expressed in the nigericin anti-cancer process. Subsequently, the bioinformatics analyses, including Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, coding and non-coding co-expression network, cis- and trans-regulation predictions and protein-protein interaction (PPI) network, were applied to annotate the potential regulatory mechanisms among these coding and non-coding RNAs during the nigericin anti-cancer process.

Conclusions: These findings provided new insight into the molecular mechanism of nigericin toward cancer cells, and suggested a possible clinical application in PC.

Ciprofloxacin promotes polarization of CD86+CD206‑ macrophages to suppress liver cancer

Gut microbiota can promote tumor development by producing toxic metabolites and inhibiting the function of immune cells. Previous studies have demonstrated that gut microbiota can reach the liver through the circulation and promote the occurrence of liver cancer. Ciprofloxacin, an effective broad‑spectrum antimicrobial agent, can promote cell apoptosis and regulate the function of immune cells. As an important part of the tumor microenvironment, macrophages play an important role in tumor regulation. The present study demonstrated that the treatment of macrophages with ciprofloxacin was able to promote the production of interleukin‑1β, tumor necrosis factor‑α and the polarization of CD86+CD206‑ macrophages, while inhibiting the polarization of CD86‑CD206+ macrophages. This transformation may help macrophages promote tumor cell apoptosis, inhibit tumor cell proliferation, reduce metastasis and downregulate the phosphoinositide 3‑kinase/AKT signaling pathway in liver cancer cell lines. In vivo experiments demonstrated that macrophages treated with ciprofloxacin inhibited the growth of subcutaneous implanted tumors in nude mice. In conclusion, the findings of the present study indicated that ciprofloxacin may inhibit liver cancer by upregulating the expression of CD86+CD206‑ macrophages. This study further revealed the biological mechanism underlying the potential value of ciprofloxacin in antitumor therapy and provided new targets for the treatment of liver cancer.

The dual roles of calycosin in growth inhibition and metastatic progression during pancreatic cancer development: A "TGF-β paradox"

BACKGROUND

Calycosin is a bioactive isoflavonoid of the medicinal plant Astragalus membranaceus that exhibits a wide range of pharmacological properties. In the present study, we have attempted to explore the anti-tumorigenic potential of calycosin in pancreatic cancer.

METHODS

MTT assay was used to determine cancer cell viability. Cell cycle analysis and detection of apoptosis were performed using flow cytometry. A wound healing assay was employed to study the migratory activity of cancer cells. Western blotting and RT-PCR were used to explore the mechanism by assessing the target proteins and genes. An orthotopic tumor xenograft mouse model was also used to study the drug effects in vivo.

RESULTS

Calycosin inhibited the growth of pancreatic cancer cells by inducing p21^Waf1/Cip1-induced cell cycle arrest and caspase-dependent apoptosis. Alternatively, it also promoted MIA PaCa-2 cell migration by eliciting epithelial-mesenchymal transition (EMT) and matrix metalloproteinase activation. In vivo study has confirmed that calycosin would provoke the pro-invasive and angiogenic drive and subsequent EMT in pancreatic tumors. Further mechanistic study suggests that induction of the Raf/MEK/ERK pathway and facilitated polarization of M2 tumor-associated macrophage in the tumor microenvironment both contribute to the pro-metastatic potential of calycosin. These events appear to be associated with increased expression of TGF-β1 at both transcriptional and post-translational levels, which may explain the paradoxical drug actions since TGF-β has been implicated to play dual roles as both tumor suppressor and tumor promoter in pancreatic cancer development.

CONCLUSION

Findings of this study provide innovative insights about the impact of calycosin in pancreatic cancer progression through induction of cell cycle arrest and apoptosis while possessing certain tumor-promoting property by modulation of the tumor microenvironment.

BAF45D knockdown decreases cell viability, inhibits colony formation, induces cell apoptosis and S-phase arrest in human pancreatic cancer cells

Pancreatic cancer, an extremely aggressive malignancy, is resistant to chemo- or radiotherapy. The rapid progression of pancreatic cancer without distinctive clinical sign makes early diagnosing and/or treating very difficult. BAF45D, a member of the d4 domain family, is involved in oncogenic processes. However, the role of BAF45D in pancreatic tumorigenesis is largely unclear. Our goal is to examine BAF45D protein expression after lentivirus-mediated Baf45d RNAi and explore the effects of BAF45D knockdown on cell proliferation, cell apoptosis, and cell cycle of human pancreatic cancer cells. Here our results showed that Baf45d RNAi downregulated BAF45D protein levels and decreased cell viability, increased cell apoptosis, and decreased colony formation in BxPC-3 cells. Moreover, BAF45D knockdown induced S-phase arrest in BxPC-3 cells. Our results here suggest that BAF45D may play a crucial role in tumorigenic properties of human pancreatic cancer cells.

LncRNA MEG3 influences the proliferation and apoptosis of psoriasis epidermal cells by targeting miR-21/caspase-8

Background

It was reported that microRNA-21(miR-21) was differentially expressed in the keratinocytes of psoriasis patients, and it may influence the apoptosis and proliferation of cells. The role of lncRNA maternally expressed gene3 (MEG3), a competing endogenous RNAs of miR-21, in the progression of psoriasis remains unclear. We aimed to unfold the influence of MEG3 and miR-21 on the proliferation and apoptosis of psoriasis epidermal cells.

Methods

50μg/L TNF-α was used to treat HaCaTs and NHEKs cells for 24 h, and then different experiments were conducted. qRT-PCR were applied for measuring the mRNA level of MEG3, miR-2, and caspase-8, and the protein expression of caspase-8 was measured with western blotting. Flow cytometry was used for assessing apoptosis. Cell proliferation was detected using MTT and colony formation assays. Dual luciferase reporter assay was applied for confirming the binding site between MEG3 and miR-21, miR-21 and Caspase-8.

Results

A cell model for in vitro studying the role of MEG3 in psoriasis pathophysiology was established using HaCaT and HHEKs. MEG3 was significantly down-regulated in HaCaT, HHEKs, and psoriatic skin samples. MEG3 inhibits proliferation and promotes apoptosis of Activated-HaCaT (Act-HaCaT) and Activated-HHEKs (Act- HHEK) by regulating miR-21, and the binding site between MEG3 and miR-21 was identified. We also found that miR-21 could inhibit the level of caspase-8 and identified the binding site between caspase-8 and miR-21. Some down-stream proteins of caspase-8, Cleaved caspase-8, cytc, and apaf-1 were regulated by miR-21 and MEG3.

Conclusion

MEG3/miR-21 axis may regulate the expression of caspase-8, and further influence the proliferation and apoptosis of psoriasis keratinocyte, Act-HaCaT and Act- HHEK. Therefore, our findings may provide a new thought for the study of pathogenesis and treatment of psoriasis.