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.

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.

Ciprofloxacin and Levofloxacin as Potential Drugs in Genitourinary Cancer Treatment-The Effect of Dose-Response on 2D and 3D Cell Cultures

Introduction: Introducing new drugs for clinical application is a very difficult, long, drawn-out, and costly process, which is why drug repositioning is increasingly gaining in importance. The aim of this study was to analyze the cytotoxic properties of ciprofloxacin and levofloxacin on bladder and prostate cell lines in vitro. Methods: Bladder and prostate cancer cell lines together with their non-malignant counterparts were used in this study. In order to evaluate the cytotoxic effect of both drugs on tested cell lines, MTT assay, real-time cell growth analysis, apoptosis detection, cell cycle changes, molecular analysis, and 3D cultures were examined. Results: Both fluoroquinolones exhibited a toxic effect on all of the tested cell lines. In the case of non-malignant cell lines, the cytotoxic effect was weaker, which was especially pronounced in the bladder cell line. A comparison of both fluoroquinolones showed the advantage of ciprofloxacin (lower doses of drug caused a stronger cytotoxic effect). Both fluoroquinolones led to an increase in late apoptotic cells and an inhibition of cell cycle mainly in the S phase. Molecular analysis showed changes in BAX, BCL2, TP53, and CDKN1 expression in tested cell lines following incubation with ciprofloxacin and levofloxacin. The downregulation of topoisomerase II genes (TOP2A and TOP2B) was noticed. Three-dimensional (3D) cell culture analysis confirmed the higher cytotoxic effect of tested fluoroquinolone against cancer cell lines. Conclusions: Our results suggest that both ciprofloxacin and levofloxacin may have great potential, especially in the supportive therapy of bladder cancer treatment. Taking into account the low costs of such therapy, fluoroquinolones seem to be ideal candidates for repositioning into bladder cancer therapeutics.

Repositioning of fluoroquinolones from antibiotic to anti-cancer agents: An underestimated truth

Increasing development costs and higher failure rate in clinical trials has reduced the repertoire of newer drugs in the market for clinical use. The most appropriate approach to end the search for newer drugs is "Repositioning", as it requires less time and money to explore new indication of existing drug or failed drug. In the past, several drugs have been repositioned for different indication but the full potential remains unharnessed. With rise in cancer prevalence and treatment costs, it is imperative to search for newer drugs and the use of repositioning approach may help us. Fluoroquinolones has been used as antibiotics for over four decades now, but recent research highlighted their use as pharmacological compounds with multifaceted implication. Repositioning of fluoroquinolones into anti-cancer molecule seems to be a highly plausible option owing to their profound immunomodulatory, pro-apoptotic, anti-proliferative and anti-metastatic potential. The present review provides a comprehensive account of the recent and past explorations pertaining to the anti-cancer activity of fluoroquinolones and also discusses the various approaches that are being considered to remodel them for the treatment of cancer.

Epirubicin suppresses proliferative and metastatic potential by downregulating transforming growth factor-β-induced expression in urothelial carcinoma

Transforming growth factor‐β‐induced (TGFΒI) is considered to be a vital gene in several carcinomas. In this study we determined the effect of TGFBI on the proliferative and metastatic potential of human urothelial carcinoma (UC) cells as well as its mRNA and protein expression, which were detected by RT‐PCR and western blot, respectively. UC cell proliferation was analyzed by WST‐1 assay and Hoechst 33258 staining. The effect of TGFBI on UC cell metastasis was analyzed using adhesion, migration and invasion assays. We found that TGFBI increased the proliferation of UC cells. Moreover, TGFBI enhanced the adhesion, migration and invasion of UC cells by upregulating MMP‐2, MMP‐9 and calpain‐2 expression. We evaluated the effect of Epirubicin (EPI) on the regulation of TGFBI expression and found that TGFBI acts as a downstream target of EPI and is suppressed by EPI in UC cells. EPI is more effective in inhibiting the proliferation and metastasis of UC cells with high TGFBI expression. This study demonstrates that TGFBI might lead to tumorigenesis and progression of UC and those cells with high TGFBI expression may be vulnerable to relapse. EPI could prove to be a therapeutic option in patients with high TGFBI expressing UC cells.

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

Background

Pancreatic cancer, one of the most dreadful gastrointestinal tract malignancies, with the current chemotherapeutic drugs has posed a major impediment owing to poor prognosis and chemo-resistance thereby suggesting critical need for additional drugs as therapeutics in combating the situation. Fluoroquinolones have shown promising and significant anti-tumor effects on several carcinoma cell lines.

Methods

Previously, we reported growth inhibitory effects of fourth generation fluoroquinolone Gatifloxacin, while in the current study we have investigated the anti-proliferative and apoptosis-inducing mechanism of older generation fluoroquinolones Moxifloxacin and Ciprofloxacin on the pancreatic cancer cell-lines MIA PaCa-2 and Panc-1. Cytotoxicity was measured by MTT assay. Apoptosis induction was evaluated using annexin assay, cell cycle assay and activation of caspase-3, 8, 9 were measured by western blotting and enzyme activity assay.

Results

Herein, we found that both the fluoroquinolones suppressed the proliferation of pancreatic cancer cells by causing S-phase arrest and apoptosis. Blockade in S-phase of cell cycle was associated with decrease in the levels of p27, p21, CDK2, cyclin-A and cyclin-E. Herein we also observed triggering of extrinsic as well as intrinsic mitochondrial apoptotic pathway as suggested by the activation of caspase-8, 9, 3, and Bid respectively. All this was accompanied by downregulation of antiapoptotic protein Bcl-xL and upregulation of proapoptotic protein Bak. Our results strongly suggest the role of extracellular-signal-regulated kinases (ERK1/2), but not p53, p38 and c-JUN N-terminal kinase (JNK) in fluoroquinolone induced growth inhibitory effects in both the cell lines. Additionally, we also found both the fluoroquinolones to augment the apoptotic effects of broad spectrum anticancer drug Cisplatin via ERK.

Conclusion

The fact that these fluoroquinolones synergize the effect of cisplatin opens new insight into therapeutic index in treatment of pancreatic cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1560-y) contains supplementary material, which is available to authorized users.

Preclinical optimization of a broad-spectrum anti-bladder cancer tri-drug regimen via the Feedback System Control (FSC) platform

Therapeutic outcomes of combination chemotherapy have not significantly advanced during the past decades. This has been attributed to the formidable challenges of optimizing drug combinations. Testing a matrix of all possible combinations of doses and agents in a single cell line is unfeasible due to the virtually infinite number of possibilities. We utilized the Feedback System Control (FSC) platform, a phenotype oriented approach to test 100 options among 15,625 possible combinations in four rounds of assaying to identify an optimal tri-drug combination in eight distinct chemoresistant bladder cancer cell lines. This combination killed between 82.86% and 99.52% of BCa cells, but only 47.47% of the immortalized benign bladder epithelial cells. Preclinical in vivo verification revealed its markedly enhanced anti-tumor efficacy as compared to its bi- or mono-drug components in cell line-derived tumor xenografts. The collective response of these pathways to component drugs was both cell type- and drug type specific. However, the entire spectrum of pathways triggered by the tri-drug regimen was similar in all four cancer cell lines, explaining its broad spectrum killing of BCa lines, which did not occur with its component drugs. Our findings here suggest that the FSC platform holdspromise for optimization of anti-cancer combination chemotherapy.

Effects of two low-shrinkage composites on dental stem cells (viability, cell damaged or apoptosis and mesenchymal markers expression)

To investigate the effects of new two low-shrinkage composites SDR(®) and Venus(®)Bulk Fill on the cell viability, cellular damage and expression of mesenchymal markers on dental stem cells. Specimens from two low-shrinkage composites were eluted with culture medium for 24 h. After 24 h of incubation, cytotoxicity of elutes were evaluated by MTT assay; apoptosis was determined using the DNA-specific fluorochrome Hoechst 33342 and the mesenchymal stem cells markers expression was analyzed by immunofluorescence staining. After 24 h of cell exposure to each extract media, dental stem cells expressed MSCs markers. The interaction among the material and cell line was not significantly correlated [F(1,60) = 2.251, P = 0.39], whereas statistically significant differences among cells lines were observed [F(1,60) = 9.157, P = 0.004], being dental pulp stem cells more resistant that periodontal ligament stem cells. Also, we did not find any significant effect between the tested materials [F(1,60) = 0.090, P = 0.765]. Furthermore, a very low proportion of exposed cells showed condensed or fragmented nuclei, typical of apoptotic cells at 24 h. The results suggest that SDR(®) and Venus(®) Bulk fill and should be considered when selecting an appropriate resin-based dental restorative material.