Platinum-induced kidney damage: Unraveling the DNA damage response (DDR) of renal tubular epithelial and glomerular endothelial cells following platinum injury

Persisting blood-brain barrier disruption following cisplatin treatment in a mouse model of chemotherapy-associated cognitive impairment

Chemotherapy-related cognitive impairment, commonly referred to as "chemobrain," significantly affects cancer survivors' quality of life, yet its underlying mechanisms remain unclear. Most chemotherapeutic agents cannot cross the blood-brain barrier (BBB), yet they cause central nervous system side effects, suggesting alternative pathways of toxicity. Given that these drugs interact with the cerebrovascular endothelium at their highest concentrations, it is logical to hypothesize that endothelial damage contributes to these effects. Our recent studies demonstrated that paclitaxel-induced cognitive impairment in a mouse model results in a partial BBB disruption and subsequent neuroinflammation, mediated by chemotherapy-induced endothelial senescence. In this pilot study, we used two-photon microscopy to assess BBB permeability in mice receiving a clinically relevant cisplatin regimen, evaluating the leakage of fluorescent dextran tracers of varying molecular weights. Two months post-treatment, cisplatin-treated mice exhibited significantly increased BBB permeability to smaller molecular tracers (40 kDa, 3 kDa, and 0.3 kDa) compared to controls, indicating sustained BBB disruption. These results align with our findings for paclitaxel and suggest that chemotherapy-induced endothelial damage and senescence play a central role in cognitive impairments. Interventions targeting endothelial health could mitigate these long-term effects, improving cognitive outcomes for cancer survivors.

Hybrid Molecules Containing Methotrexate, Vitamin D, and Platinum Derivatives: Synthesis, Characterization, In Vitro Cytotoxicity, In Silico ADME Docking, Molecular Docking and Dynamics

Designing hybrid-based drugs is one promising strategy for developing effective anticancer drugs that explore combination therapy to enhance treatment efficacy, overcome the development of drug resistance, and lower treatment duration. Bisphosphonates and Vitamin D are commonly administered drugs for the treatment of bone diseases and the prevention of bone metastases. Platinum-based and methotrexate are widely used anticancer drugs in clinics. However, their use is hampered by adverse side effects. Hybrid-based compounds containing either bisphosphonate, vitamin D, platinum-based, or methotrexate were synthesized and characterized using FTIR, 1H-,31P, 13C-NMR, and UHPLC-HRMS which confirmed their successful synthesis. The hydroxyapatite bone binding assay revealed a promising percentage binding affinity of the bisphosphonate hybrid compounds. In vitro cytotoxicity assays on MCF-7 and HT-29 cell lines revealed a promising cytotoxic effect of hybrid 19 at 50 and 100 μg/mL on HT-29 and hybrid 15 on MCF-7 at 100 μg/mL. Molecular docking and dynamics simulation analysis revealed a binding affinity of -9.70 kcal/mol for hybrid 15 against Human 3 alpha-hydroxysteroid dehydrogenase type 3, showing its capability to inhibit Human 3 alpha-hydroxysteroid dehydrogenase type 3. The Swiss ADME, ProTox-II, GUSAR (General Unrestricted Structure-Activity Relationships), and molecular docking and dynamics studies revealed that these compounds are promising anticancer compounds.

DNA damage caused by chemotherapy has duality, and traditional Chinese medicine may be a better choice to reduce its toxicity

Background

DNA damage induced by chemotherapy has duality. It affects the efficacy of chemotherapy and constrains its application. An increasing number of studies have shown that traditional Chinese medicine (TCM) is highly effective in reducing side-effects induced by chemotherapy due to its natural, non-toxic and many sourced from food. Recent advancements have demonstrated survival rates are improved attributable to effective chemotherapy. DNA damage is the principal mechanism underlying chemotherapy. However, not all instances of DNA damage are beneficial. Chemotherapy induces DNA damage in normal cells, leading to side effects. It affects the efficacy of chemotherapy and constrains its application.

Objectives

This review aims to summarize the dual nature of DNA damage induced by chemotherapy and explore how TCM can mitigate chemotherapy-induced side effects.

Results

The review summarized the latest research progress in DNA damage caused by chemotherapy and the effect of alleviating side effects by TCM. It focused on advantages and disadvantages of chemotherapy, the mechanism of drugs and providing insights for rational and effective clinical treatment and serving as a basis for experiment. In this review, we described the mechanisms of DNA damage, associated chemotherapeutics, and their toxicity. Furthermore, we explored Chinese herb that can alleviate chemotherapy-induced side-effects.

Conclusion

We highlight key mechanisms of DNA damage caused by chemotherapeutics and discuss specific TCM herbs that have shown potential in reducing these side effects. It can provide reference for clinical and basic research.

Roles of DNA damage in renal tubular epithelial cells injury

The prevalence of renal diseases including acute kidney injury (AKI) and chronic kidney disease (CKD) is increasing worldwide. However, the pathogenesis of most renal diseases is still unclear and effective treatments are still lacking. DNA damage and the related DNA damage response (DDR) have been confirmed as common pathogenesis of acute kidney injury and chronic kidney disease. Reactive oxygen species (ROS) induced DNA damage is one of the most common types of DNA damage involved in the pathogenesis of acute kidney injury and chronic kidney disease. In recent years, several developments have been made in the field of DNA damage. Herein, we review the roles and developments of DNA damage and DNA damage response in renal tubular epithelial cell injury in acute kidney injury and chronic kidney disease. In this review, we conclude that focusing on DNA damage and DNA damage response may provide valuable diagnostic biomarkers and treatment strategies for renal diseases including acute kidney injury and chronic kidney disease.

In Vitro and In Vivo Nephroprotective Effects of Nelumbo nucifera Seedpod Extract against Cisplatin-Induced Renal Injury

Cisplatin has been considered a chemotherapeutic drug for treating human tumors, and one of the noteworthy side effects of cisplatin is nephrotoxicity. Amelioration of cisplatin-induced nephrotoxicity is necessary. Lotus seedpod extract (LSE) mainly composed of quercetin-3-glucuronide has been revealed for antioxidant and anti-tumor effects. However, the effects of LSE on cisplatin-induced nephrotoxicity are still unknown. This study aims to explore the in vitro and in vivo protective effect and possible mechanism of LSE on cisplatin-induced nephrotoxicity. Results showed that co-treatment of LSE with cisplatin raised the viability of rat renal tubular epithelial NRK-52E cells and decreased oxidative stress and cell apoptosis when compared to the cells treated with cisplatin alone. The molecular mechanisms analyzed found that LSE could reduce the expressions of apoptotic factors, including Bax, Bad, t-Bid, and caspases. In the in vivo study, LSE improved the cisplatin-induced levels of serum markers of kidney function, glomerular atrophy, and the degree of apoptosis in the kidneys. This is the first study to display that LSE prevents cisplatin-induced nephrotoxicity by reducing oxidative stress and apoptosis. Thus, LSE could be a novel and natural chemoprotective agent for cisplatin chemotherapy in the future.

Improvement of Kiteplatin Efficacy by a Benzoato Pt(IV) Prodrug Suitable for Oral Administration

Kiteplatin, [PtCl₂(cis-1,4-DACH)] (DACH = diaminocyclohexane), contains an isomeric form of the oxaliplatin diamine ligand trans-1R,2R-DACH and has been proposed as a valuable drug candidate against cisplatin- and oxaliplatin-resistant tumors, in particular, colorectal cancer. To further improve the activity of kiteplatin, it has been transformed into a Pt(IV) prodrug by the addition of two benzoato groups in the axial positions. The new compound, cis,trans,cis-[PtCl₂(OBz)₂(cis-1,4-DACH)] (1; OBz = benzoate), showed cytotoxic activity at nanomolar concentration against a wide panel of human cancer cell lines. Based on these very promising results, the investigation has been extended to the in vivo activity of compound 1 in a Lewis Lung Carcinoma (LLC) model and its suitability for oral administration. Compound 1 resulted to be remarkably stable in acidic conditions (pH 1.5 to mimic the stomach environment) undergoing a drop of the initial concentration to ~60% of the initial one only after 72 h incubation at 37 °C; thus resulting amenable for oral administration. Interestingly, in a murine model (2·10⁶ LLC cells implanted i.m. into the right hind leg of 8-week old male and female C57BL mice), a comparable reduction of tumor mass (~75%) was observed by administering compound 1 by oral gavage and the standard drug cisplatin by intraperitoneal injection, thus indicating that, indeed, there is the possibility of oral administration for this dibenzoato prodrug of kiteplatin. Moreover, since the mechanism of action of Pt(IV) prodrugs involves an initial activation by chemical reduction to cytotoxic Pt(II) species, the reduction of 1 by two bioreductants (ascorbic acid/sodium ascorbate and glutathione) was investigated resulting to be rather slow (not complete after 120 h incubation at 37 °C). Finally, the neurotoxicity of 1 was evaluated using an in vitro assay.

DNA damage is overcome by TRIP13 overexpression during cisplatin nephrotoxicity

Cisplatin is a commonly used chemotherapeutic agent to treat a wide array of cancers that is frequently associated with toxic injury to the kidney due to oxidative DNA damage and perturbations in cell cycle progression leading to cell death. In this study, we investigated whether thyroid receptor interacting protein 13 (TRIP13) plays a central role in the protection of the tubular epithelia following cisplatin treatment by circumventing DNA damage. Following cisplatin treatment, double-stranded DNA repair pathways were inhibited using selective blockers to proteins involved in either homologous recombination or non-homologous end joining. This led to increased blood markers of acute kidney injury (AKI) (creatinine and neutrophil gelatinase–associated lipocalin), tubular damage, activation of DNA damage marker (γ-H2AX), elevated appearance of G2/M blockade (phosphorylated histone H3 Ser10 and cyclin B1), and apoptosis (cleaved caspase-3). Conditional proximal tubule–expressing Trip13 mice were observed to be virtually protected from the cisplatin nephrotoxicity by restoring most of the pathological phenotypes back toward normal conditions. Our findings suggest that TRIP13 could circumvent DNA damage in the proximal tubules during cisplatin injury and that TRIP13 may constitute a new therapeutic target in protecting the kidney from nephrotoxicants and reduce outcomes leading to AKI.

Metal complexes against breast cancer stem cells

With the highest incidence, breast cancer is the leading cause of cancer deaths among women in the world. Tumor metastasis is the major contributor of high mortality in breast cancer, and the existence of cancer stem cells (CSCs) has been proven to be the cause of tumor metastasis. CSCs are a small proportion of tumor cells, and they are associated with self-renewal and tumorigenic potential. Given the significance of CSCs in tumor initiation, expansion, relapse, resistance, and metastasis, studies should investigate and discover effective anticancer agents that can not only inhibit the proliferation of differentiated tumor cells but also reduce the tumorigenic capability of CSCs. Thus, new therapies must be discovered to treat and prevent this severely hazardous disease of human beings. The success of platinum complexes in cancer treatment has laid the basic foundation for the utilization of metal complexes in the treatment of malignant cancers, in particular the highly aggressive triple-negative breast cancer. Importantly, metal complexes currently have diverse and versatile competences in the therapeutic targeting of CSCs. The anti-CSC properties provide a strong impetus for the development of novel metal-based compounds for the targeting of CSCs and treatment of chemotherapy-resistant and relapsed tumors. In this review, we provide the latest advances in metal complexes including platinum, ruthenium, osmium, iridium, manganese, cobalt, nickel, copper, zinc, palladium, and tin complexes against breast CSCs obtained over the past decade, with pertinent literature including those published until 2021.

In Vitro Nephrotoxicity Studies of Established and Experimental Platinum-Based Compounds

Cisplatin is one of the most commonly used drugs for the treatment of various solid cancers. However, its efficacy is restricted by severe side effects, especially dose-limiting nephrotoxicity. New platinum-based compounds are designed to overcome this limitation. Previous investigations showed that the platinum(IV)–nitroxyl complex PN149 is highly cytotoxic in various tumor cell lines. In the present study, investigations with PN149 were extended to normal human kidney tubule epithelia. Coincident with higher intracellular platinum accumulation, the cytotoxicity of PN149 in the proximal tubule epithelial cell line ciPTEC was more pronounced compared to the established platinum chemotherapeutics cisplatin, carboplatin and oxaliplatin. Quantitative gene expression profiling revealed the induction of ROS-inducible and anti-oxidative genes, suggesting an oxidative stress response by PN149. However, in contrast to cisplatin, no pro-inflammatory response was observed. Genes coding for distinct DNA damage response factors and genes related to apoptosis were up-regulated, indicating the activation of the DNA damage response system and induction of the apoptotic cascade by PN149. Altogether, a comparable transcriptional response was observed for PN149 and the platinum chemotherapeutics. However, the lack of inflammatory activity, which is a possible cause contributing to toxicity in human renal proximal tubule epithelia, might indicate the reduced nephrotoxic potential of PN149.

Effects of 5-HT₃ receptor antagonists on cisplatin-induced kidney injury

Nausea, vomiting, and renal injury are the common adverse effects associated with cisplatin. Cisplatin is excreted via the multidrug and toxin release (MATE) transporter, and the involvement of the MATE transporter in cisplatin‐induced kidney injury has been reported. The MATE transporter is also involved in the excretion of ondansetron, but the effects of 5‐HT₃ receptor antagonists used clinically for cisplatin‐induced renal injury have not been elucidated. Therefore, the aim of this study was to investigate the effects of 5‐HT₃ receptor antagonists in a mouse model of cisplatin‐induced kidney injury and to validate the results using medical big data analysis of more than 1.4 million reports and a survey of 3000 hospital medical records. The concomitant use of a first‐generation 5‐HT₃ receptor antagonist (ondansetron, granisetron, or ramosetron) significantly increased cisplatin accumulation in the kidneys and worsened renal damage. Conversely, the concomitant use of palonosetron had no effect on renal function compared with the use of cisplatin alone. Furthermore, an analysis of data from the US Food and Drug Administration Adverse Event Reporting System and retrospective medical records revealed that the combination treatment of cisplatin and a first‐generation 5‐HT₃ receptor antagonist significantly increased the number of reported renal adverse events compared with the combination treatment of cisplatin and a second‐generation 5‐HT₃ receptor antagonist. These results suggest that compared with the first‐generation antagonists, second‐generation 5‐HT₃ receptor antagonists do not worsen cisplatin‐induced acute kidney injury. The findings should be validated in a prospective controlled trial before implementation in clinical practice.

Targeting of radioactive platinum-bisphosphonate anticancer drugs to bone of high metabolic activity

Platinum-based chemotherapeutics exhibit excellent antitumor properties. However, these drugs cause severe side effects including toxicity, drug resistance, and lack of tumor selectivity. Tumor-targeted drug delivery has demonstrated great potential to overcome these drawbacks. Herein, we aimed to design radioactive bisphosphonate-functionalized platinum (^195mPt-BP) complexes to confirm preferential accumulation of these Pt-based drugs in metabolically active bone. In vitro NMR studies revealed that release of Pt from Pt BP complexes increased with decreasing pH. Upon systemic administration to mice, Pt-BP exhibited a 4.5-fold higher affinity to bone compared to platinum complexes lacking the bone-seeking bisphosphonate moiety. These Pt-BP complexes formed less Pt-DNA adducts compared to bisphosphonate-free platinum complexes, indicating that in vivo release of Pt from Pt-BP complexes proceeded relatively slow. Subsequently, radioactive ^195mPt-BP complexes were synthesized using ^195mPt(NO₃)₂(en) as precursor and injected intravenously into mice. Specific accumulation of ^195mPt-BP was observed at skeletal sites with high metabolic activity using micro-SPECT/CT imaging. Furthermore, laser ablation-ICP-MS imaging of proximal tibia sections confirmed that ^195mPt BP co-localized with calcium in the trabeculae of mice tibia.

Evaluation of mutagenic activity of platinum complexes in somatic cells of Drosophila melanogaster

Cisplatin, carboplatin, and oxaliplatin are some of the most often used alkylating chemotherapeutic agents. In view of the paucity of data on the genotoxicity of oxaliplatin, this study compares the mutagenic activity of cisplatin (0.006, 0.012, 0.025, 0.05 mM), carboplatin (0.1, 0.2, 0,5, 1.0 mM), and oxaliplatin (0.1, 0.2, 0,5, 1.0 mM) using the somatic mutation and recombination test (SMART) in Drosophila melanogaster. Standard and high-bioactivation crosses of the drosophilid were used, which present basal and high levels of cytochrome P450 (CYP450) metabolization enzymes, respectively. All concentrations of cisplatin and carboplatin induced lesions in genetic material in both crosses, while oxaliplatin was mutagenic only to high bioactivation flies treated with 0.1, 0.5 and 1 mM of the compound. No significant differences were observed between genotoxicity values of cisplatin and carboplatin. However, CYP450 enzymes may have affected the mutagenic action of oxaliplatin. Carboplatin induced mainly mutation events, while cisplatin triggered mostly mutation and recombination events when low and high doses were used. Most events induced by oxaliplatin were generated by somatic recombination. Important differences were observed in genotoxic potential of platinum chemotherapeutic compounds, possibly due to the origin and type of the lesions induced in DNA and the repair mechanisms involved.

Anemoside B4 attenuates nephrotoxicity of cisplatin without reducing anti-tumor activity of cisplatin

BACKGROUND

Cisplatin is a highly effective chemotherapeutic agent commonly used in the treatment of a wide variety of malignancies. However, its clinical usage is severely limited by its serious side effects, especially nephrotoxicity. Anemoside B4, is a major saponins, rich in root of Pulsatilla chinensis (Bunge), has anti-inflammation in vitro. However, the antioxidant or anti-inflammatory effects of anemoside B4 in cisplatin-induced nephrotoxicity have not been clearly demonstrated.

PURPOSE

In this study, we investigated whether anemoside B4 exhibits protective effects against cisplatin-induced nephrotoxicity involving antioxidant or anti-apoptosis effects.

METHOD

To clarify it, the effects of anemoside B4 on HEK 293 cell viability was measured by CCK8 kits, intracellular antioxidant capacity including glutathione reduced (GSH), catalase (CAT) were estimated using chemical kits, apoptosis rate and intracellular reactive oxygen species (ROS) was analyzed by flow cytometry, apoptosis protein was measured by western blotting. In vivo model of cisplatin-induced mice acute renal failure was performed to evaluate the properties of anemoside B4. Besides, to evaluate the effect of anemoside B4 on the anti-tumor activity of cisplatin, S₁₈₀ xenograft models were used.

RESULTS

Anemoside B4 potently increased cisplatin-treated HEK 293T cells viability on the concentration and time manners and inhibited cells apoptosis, as demonstrated by the decreased cleaved PARP protein expressions. Anemoside B4 decreased reactive oxygen species (ROS) content and improved superoxide dismutase (SOD) activity. In vivo experiment showed that pretreatment with anemoside B4 effectively adjusted body weight and kidney index, and reduced cisplatin-elevated blood urea nitrogen (BUN) and creatinine (CREA) levels, as well as ameliorated the histopathological damage. Further studies showed that anemoside B4 did not reduce antitumor activity of cisplatin in murine S₁₈₀ cancer xenograft tumor models. In addition, anemoside B4 per set showed low toxicity in mice.

CONCLUSION

The strong antioxidant and anti-apoptosis effects of anemoside B4 may provide therapeutic potential for cisplatin-induced nephrotoxicity without compromising its therapeutic efficiency.

Multiple Targets of 3-Dehydroxyceanothetric Acid 2-Methyl Ester to Protect Against Cisplatin-Induced Cytotoxicity in Kidney Epithelial LLC-PK1 Cells

Chronic exposure to cisplatin, a potent anticancer drug, causes irreversible kidney damage. In this study, we investigated the protective effect and mechanism of nine lupane- and ceanothane-type triterpenoids isolated from jujube (Ziziphus jujuba Mill., Rhamnaceae) on cisplatin-induced damage to kidney epithelial LLC-PK1 cells via mitogen-activated protein kinase (MAPK) and apoptosis pathways. Cisplatin-induced LLC-PK1 cell death was most significantly reduced following treatment with 3-dehydroxyceanothetric acid 2-methyl ester (3DC2ME). Additionally, apoptotic cell death was significantly reduced. Expression of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p38 was markedly suppressed by 3DC2ME, indicating inhibition of the MAPK pathway. Treatment with 3DC2ME also significantly reduced expression of active caspase-8 and -3, Bcl-2-associated X protein (Bax), and B cell lymphoma 2 (Bcl-2), indicating the inhibition of apoptosis pathways in the kidneys. We also applied the network pharmacological analysis and identified multiple targets of 3DC2ME related to MAPK signaling pathway and apoptosis.

Poly(alkylidenimine) Dendrimers Functionalized with the Organometallic Moiety [Ru(η⁵-C₅H₅)(PPh₃)₂]⁺ as Promising Drugs Against Cisplatin-Resistant Cancer Cells and Human Mesenchymal Stem Cells

Here and for the first time, we show that the organometallic compound [Ru(η⁵-C₅H₅)(PPh₃)₂Cl] (RuCp) has potential to be used as a metallodrug in anticancer therapy, and further present a new approach for the cellular delivery of the [Ru(η⁵-C₅H₅)(PPh₃)₂]⁺ fragment via coordination on the periphery of low-generation poly(alkylidenimine) dendrimers through nitrile terminal groups. Importantly, both the RuCp and the dendrimers functionalized with [Ru(η⁵-C₅H₅)(PPh₃)₂]⁺ fragments present remarkable toxicity towards a wide set of cancer cells (Caco-2, MCF-7, CAL-72, and A2780 cells), including cisplatin-resistant human ovarian carcinoma cell lines (A2780cisR cells). Also, RuCp and the prepared metallodendrimers are active against human mesenchymal stem cells (hMSCs), which are often found in the tumor microenvironment where they seem to play a role in tumor progression and drug resistance.

Pretreatment with taurine prevented brain injury and exploratory behaviour associated with administration of anticancer drug cisplatin in rats

The neurotoxicity associated with cisplatin treatment is one of the major side effects compromising the efficacy of the anti-cancer treatment. The present study investigated the possible protective effects of taurine, an intracellular amino acid, on cisplatin-induced brain injury and exploratory behaviour using five groups of ten female rats each. Group I received drinking water only. Group II orally received taurine alone at 200 mg/kg whereas Group III received cisplatin alone intraperitoneally at 10 mg/kg. Groups IV and V were treated with taurine at 100 and 200 mg/kg respectively for sixteen consecutive days and a single intraperitoneal injection of cisplatin on day 13 to induce neurotoxicity. Endpoint analyses using video-tracking software revealed that cisplatin administration alone caused neurobehavioral deficits evinced by marked decrease in the total distance travelled, average speed, total time mobile, total mobile episode, number of crossing and absolute turn angle. Furthermore, cisplatin alone significantly suppressed brain antioxidant defense mechanisms, elevated nitric oxide and lipid peroxidation levels whereas it increased acetylcholinesterase activity in the treated rats. However, rats pretreated with taurine exhibited significant improvement in behavioural performance and brain antioxidant status with concomitant decrease in acetylcholinesterase activity and oxidative stress indices when compared with cisplatin alone group. Histologically, taurine pretreatment prevented cisplatin-induced neuronal death in the cerebral and cerebellar cortices, caudo-putamen and hippocampus as well as abrogated cisplatin-mediated decrease in the dendritic arborization and mean diameter of the somata of pyramidal neurons in the treated rats. In conclusion, taurine may be a possible protective supplement to reduce cisplatin-induced side-effects including neurotoxicity in patients undergoing cisplatin treatment.

Cisplatin resistance in cell models: evaluation of metallomic and biological predictive biomarkers to address early therapy failure

Cisplatin, one of the most extensively used metallodrugs in cancer treatment, presents the important drawback of patient resistance. This resistance is the consequence of different processes including those preventing the formation of DNA adducts and/or their quick removal. Thus, a tool for the accurate detection and quantitation of cisplatin-induced adducts might be valuable for predicting patient resistance. To prove the validity of such an assumption, highly sensitive plasma mass spectrometry (ICP-MS) strategies were applied to determine DNA adduct levels and intracellular Pt concentrations. These two metal-relative parameters were combined with an evaluation of biological responses in terms of genomic stability (with the Comet assay) and cell cycle progression (by flow cytometry) in four human cell lines of different origins and cisplatin sensitivities (A549, GM04312, A2780 and A2780cis), treated with low cisplatin doses (5, 10 and 20 μM for 3 hours). Cell viability and apoptosis were determined as resistance indicators. Univariate linear regression analyses indicated that quantitation of cisplatin-induced G-G intra-strand adducts, measured 1 h after treatment, was the best predictor for viability and apoptosis in all of the cell lines. Multivariate linear regression analyses revealed that the prediction improved when the intracellular Pt content or the Comet data were included in the analysis, for all sensitive cell lines and for the A2780 and A2780cis cell lines, respectively. Thus, a reliable cisplatin resistance predictive model, which combines the quantitation of adducts by HPLC-ICP-MS, and their repair, with the intracellular Pt content and induced genomic instability, might be essential to identify early therapy failure.

Therapeutic potential of the phosphino Cu(I) complex (HydroCuP) in the treatment of solid tumors

[Cu(thp)₄][PF₆] (HydroCuP) is a phosphino copper(I) complex highly soluble and stable in physiological media that has been developed as a possible viable alternative to platinum-based drugs for anticancer therapy. HydroCuP potently inhibited the growth of human cancer cells derived from solid tumors by inducing endoplasmatic reticulum (ER) stress thus leading to cell death through paraptosis with a preferential efficacy against cancer rather than non-cancer cells. Aim of the present study was to assess the therapeutic potential of HydroCuP in vivo, in syngenic and xenograft murine models of solid tumors by triggering the Unfolded Protein Response (UPR) pathway. With respect to platinum drugs, HydroCuP induced a markedly higher reduction of tumor growth associated with minimal animal toxicity. In human colorectal cancer xenografts, chemotherapy with HydroCuP was extremely effective in both oxaliplatin-sensitive and resistant models. The favorable in vivo tolerability of HydroCuP was also correlated to an encouraging biodistribution profile. Additionally, no signs of drug-related neurotoxicity and nephrotoxicity were observed. Altogether, these results demonstrate that HydroCuP appears worth of further investigation to evaluate its therapeutic activity towards a broad spectrum of solid malignancies.

The Protective Effect of Naringenin-Oxime on Cisplatin-Induced Toxicity in Rats

The aim of this study is to examine the protective effect of naringenin-oxime (NOX) on cisplatin-induced major organ toxicity and DNA damage in rats. Thirty-five male Wistar albino rats were equally split into five groups as follows: control (i.p., 0.1 ml of saline), Cis administration (i.p., 7 mg/kg b.w.), NOX treatment (i.p., 20 mg/kg b.w., daily for ten days), Cis + NOX20, and Cis + NOX40 combination (i.p., 20 and 40 mg/kg b.w., daily for ten days). Serum and peripheral blood mononuclear leukocytes (PBMC) were obtained from blood. Malondialdehyde, glutathione, total antioxidant and oxidant status, and catalase were measured in serum, liver, and kidney, and oxidative stress index was calculated. In parallel, paraoxonase and arylesterase activities were tested in liver and serum. We used 8-OHdOG as a marker for DNA damage in serum via ELISA and in PMBC via comet assay. Treatment with Cis elevated the levels of serum biochemical parameters, oxidative stress, and DNA damage. Pretreatments of NOX restored biochemical and oxidative stress parameters in serum, renal, and liver tissues (p < 0.01) and reduced 8-OHdG level, a finding further supported by comet assay in PBMC. Observations of the present study support the fact that treatment with NOX prevents Cis-induced hepatotoxicity, nephrotoxicity, and genotoxicity by restoring antioxidant system.

MiR-30c regulates cisplatin-induced apoptosis of renal tubular epithelial cells by targeting Bnip3L and Hspa5

As a common anticancer drug, cisplatin has been widely used for treating tumors in the clinic. However, its side effects, especially its nephrotoxicity, noticeably restrict the application of cisplatin. Therefore, it is imperative to investigate the mechanism of renal injury and explore the corresponding remedies. In this study, we showed the phenotypes of the renal tubules and epithelial cell death as well as elevated cleaved-caspase3- and TUNEL-positive cells in rats intraperitoneally injected with cisplatin. Similar cisplatin-induced cell apoptosis was found in HK-2 and NRK-52E cells exposed to cisplatin as well. In both models of cisplatin-induced apoptosis in vivo and in vitro, quantitative PCR data displayed reductions in miR-30a-e expression levels, indicating that miR-30 might be involved in regulating cisplatin-induced cell apoptosis. This was further confirmed when the effects of cisplatin-induced cell apoptosis were found to be closely correlated with alterations in miR-30c expression, which were manipulated by transfection of either the miR-30c mimic or miR-30c inhibitor in HK-2 and NRK-52E cells. Using bioinformatics tools, including TargetScan and a gene expression database (Gene Expression Omnibus), Adrb1, Bnip3L, Hspa5 and MAP3K12 were predicted to be putative target genes of miR-30c in cisplatin-induced apoptosis. Subsequently, Bnip3L and Hspa5 were confirmed to be the target genes after determining the expression of these putative genes following manipulation of miR-30c expression levels in HK-2 cells. Taken together, our current experiments reveal that miR-30c is certainly involved in regulating the renal tubular cell apoptosis induced by cisplatin, which might supply a new strategy to minimize cisplatin-induced nephrotoxicity.

Ameliorative Effect of Coenzyme Q10 and/or Candesartan on Carboplatin-Induced Nephrotoxicity: Roles of Apoptosis, Transforming Growth Factor-Β1, Nuclear Factor Kappa-B And The Nrf2/HO-1 Pathway

Background:

Carboplatin is a drug that is used for treatment of many types of cancer. However, it may produce serious nephrotoxicity. Candesartan is angiotensin II receptor antagonist employed mainly for control of hypertension. Coenzyme Q10 (CoQ10) is a fat-soluble substance which was proven to have potent antioxidant and anti-inflammatory properties.

Aim:

Our aim was to study the effects of candesartan and/or CoQ10 on carboplatin-induced nephrotoxicity in mice.

Methods:

Sixty mice were divided into 6 equal groups: Control untreated; carboplatin; carboplatin + candesartan; carboplatin + CoQ10; carboplatin + carboxymethyl cellulose; and carboplatin + candesartan + CoQ10 group. Kidney weight/body weight ratio, blood urea, serum creatinine, creatinine clearance, urinary N-acetyl beta-D-glucosaminidase (NAG), gamma glutamyl transpeptidase (GGT) and the urinary albumin excretion rate (UAER) were determined. Renal tissue catalase (CAT), glutathione reductase (GR), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), heme oxygenase-1 (HO-1), transforming growth factor beta-1 (TGF-β1), tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) were also determined, along with mitochondrial complex I activity. In addition, portions of the kidney were subjected to histopathological and immunohistochemical examination.

Results:

Candesartan and/or CoQ10 induced significant improvement of renal and mitochondrial functions with significant increase in tissue CAT, GR, Nrf2 and HO-1 content associated with significant decrease in the kidney weight/body weight ratio, tissue TGF-β1, TNF-α and IL-6 and alleviation of the histopathological and immunohistochemical changes as compared to carboplatin alone group. These effects were more significant in candesartan/CoQ10 combination group compared to either candesartan or CoQ10 alone.

Conclusion:

Candesartan/CoQ10 combination might represent a beneficial therapeutic modality for amelioration of carboplatin-induced nephrotoxicity.

Pharmacological comparison of a nonhuman primate and a rat model of oxaliplatin-induced neuropathic cold hypersensitivity

Oxaliplatin is a first‐line treatment for colorectal cancer. However, shortly following treatment, cold‐evoked hypersensitivity appears in the extremities and over time, the pain is such that oxaliplatin dosing may need to be markedly reduced or even terminated. There is currently a lack of efficacious treatments for oxaliplatin‐induced peripheral neuropathy, which is due in part to the difficulty in translating findings obtained from preclinical rodent models of chemotherapy‐induced peripheral neuropathy. Nonhuman primates (NHP) are phylogenetically closer to humans than rodents and may show drug responses that parallel those of humans. A significant decrease in tail withdrawal latency to 10°C water (“cold hypersensitivity”) was observed beginning 3 days after intravenous infusion of oxaliplatin (5 mg/kg) in Macaca fascicularis. A single treatment of duloxetine (30 mg/kg, p.o.) ameliorated oxaliplatin‐induced cold hypersensitivity, whereas pregabalin (30 mg/kg, p.o.) and tramadol (30 mg/kg, p.o.) did not. By contrast, in rats, no significant cold hypersensitivity, or increased responsiveness to acetone applied to the hind paws, was observed 3 days after the first injection of oxaliplatin (5 mg/kg, i.p., once per day, two injections). Therefore, rats were tested after six treatments of oxaliplatin, 17 days after the first treatment. All analgesics (30 mg/kg, p.o.) significantly ameliorated cold hypersensitivity in rats. The activity of analgesics in the oxaliplatin‐treated macaques parallel clinical findings. The current results indicate that the NHP could serve as a bridge species to improve translatability of preclinical findings into clinically useful treatments for oxaliplatin‐induced peripheral neuropathy.

Lovastatin prevents cisplatin-induced activation of pro-apoptotic DNA damage response (DDR) of renal tubular epithelial cells

The platinating agent cisplatin (CisPt) is commonly used in the therapy of various types of solid tumors. The anticancer efficacy of CisPt largely depends on the formation of bivalent DNA intrastrand crosslinks, which stimulate mechanisms of the DNA damage response (DDR), thereby triggering checkpoint activation, gene expression and cell death. The clinically most relevant adverse effect associated with CisPt treatment is nephrotoxicity that results from damage to renal tubular epithelial cells. Here, we addressed the question whether the HMG-CoA-reductase inhibitor lovastatin affects the DDR of renal cells by employing rat renal proximal tubular epithelial (NRK-52E) cells as in vitro model. The data show that lovastatin has extensive inhibitory effects on CisPt-stimulated DDR of NRK-52E cells as reflected on the levels of phosphorylated ATM, Chk1, Chk2, p53 and Kap1. Mitigation of CisPt-induced DDR by lovastatin was independent of the formation of DNA damage as demonstrated by (i) the analysis of Pt-(GpG) intrastrand crosslink formation by Southwestern blot analyses and (ii) the generation of DNA strand breaks as analyzed on the level of nuclear γH2AX foci and employing the alkaline comet assay. Lovastatin protected NRK-52E cells from the cytotoxicity of high CisPt doses as shown by measuring cell viability, cellular impedance and flow cytometry-based analyses of cell death. Importantly, the statin also reduced the level of kidney DNA damage and apoptosis triggered by CisPt treatment of mice. The data show that the lipid-lowering drug lovastatin extensively counteracts pro-apoptotic signal mechanisms of the DDR of tubular epithelial cells following CisPt injury.

DNA damage response in cisplatin-induced nephrotoxicity

Cisplatin and its derivatives are widely used chemotherapeutic drugs for cancer treatment. However, they have debilitating side effects in normal tissues and induce ototoxicity, neurotoxicity, and nephrotoxicity. In kidneys, cisplatin preferentially accumulates in renal tubular cells causing tubular cell injury and death, resulting in acute kidney injury (AKI). Recent studies have suggested that DNA damage and the associated DNA damage response (DDR) are an important pathogenic mechanism of AKI following cisplatin treatment. Activation of DDR may lead to cell cycle arrest and DNA repair for cell survival or, in the presence of severe injury, kidney cell death. Modulation of DDR may provide novel renoprotective strategies for cancer patients undergoing cisplatin chemotherapy.