Cisplatin induces a mitochondrial-ROS response that contributes to cytotoxicity depending on mitochondrial redox status and bioenergetic functions

Advancements of ROS-based biomaterials for sensorineural hearing loss therapy

Sensorineural hearing loss (SNHL) represents a substantial global health challenge, primarily driven by oxidative stress-induced damage within the auditory system. Excessive reactive oxygen species (ROS) play a pivotal role in this pathological process, leading to cellular damage and apoptosis of cochlear hair cells, culminating in irreversible hearing impairment. Recent advancements have introduced ROS-scavenging biomaterials as innovative, multifunctional platforms capable of mitigating oxidative stress. This comprehensive review systematically explores the mechanisms of ROS-mediated oxidative stress in SNHL, emphasizing etiological factors such as aging, acoustic trauma, and ototoxic medication exposure. Furthermore, it examines the therapeutic potential of ROS-scavenging biomaterials, positioning them as promising nanomedicines for targeted antioxidant intervention. By critically assessing recent advances in biomaterial design and functionality, this review thoroughly evaluates their translational potential for clinical applications. It also addresses the challenges and limitations of ROS-neutralizing strategies, while highlighting the transformative potential of these biomaterials in developing novel SNHL treatment modalities. This review advocates for continued research and development to integrate ROS-scavenging biomaterials into future clinical practice, aiming to address the unmet needs in SNHL management and potentially revolutionize the treatment landscape for this pervasive health issue.

Cisplatin Exposure Dysregulates Insulin Secretion in Male and Female Mice

ARTICLE HIGHLIGHTS

Cancer survivors who receive cisplatin chemotherapy have an increased risk of type 2 diabetes, but the underlying mechanisms remain unclear. The aim of this study was to investigate whether cisplatin impacts β-cell health and function, thereby contributing to increased type 2 diabetes risk in cancer survivors. In vivo and in vitro cisplatin exposure dysregulated insulin secretion in male and female mice. In vitro cisplatin exposure reduced oxygen consumption, impaired β-cell exocytotic capacity, and altered expression of genes within the insulin secretion pathway in mouse islets. Understanding how chemotherapeutic drugs cause β-cell injury is critical for designing targeted interventions to reduce the risk of cancer survivors developing type 2 diabetes after treatment.

Unraveling the role of deubiquitinating enzymes on cisplatin resistance in several cancers

The use of platinum-based drugs in cancer treatment is one of the most common methods in chemotherapy. Especially, cisplatin induces cell death by interrupting DNA synthesis by binding to the DNA bases, thereby leading to the apoptosis via multiple pathways. However, the major hurdle in chemotherapy is drug resistance. To overcome drug resistance, the ubiquitin-proteasome system (UPS) has emerged as a potential therapeutic target. The UPS is a pivotal signaling pathway that regulates the majority of cellular proteins by attaching ubiquitin to substrates, leading to proteasomal degradation. Conversely, deubiquitinating enzymes (DUBs) remove tagged ubiquitin from the substrate and inhibit degradation, thereby maintaining proteostasis. Recently, studies have been conducted to identify the substrates of DUBs and investigated the cellular mechanisms, and now the development of therapeutics using DUB inhibitors is in clinical trials. However, the mechanism of the DUB response to cisplatin remains still unclear. In this review, we summarize the research reported on the function of DUBs responding to cisplatin.

Mitochondrial unfolded protein response-dependent β-catenin signaling promotes neuroendocrine prostate cancer

The mitochondrial unfolded protein response (UPRmt) maintains mitochondrial quality control and proteostasis under stress conditions. However, the role of UPRmt in aggressive and resistant prostate cancer is not clearly defined. We show that castration-resistant neuroendocrine prostate cancer (CRPC-NE) harbored highly dysfunctional oxidative phosphorylation (OXPHOS) Complexes. However, biochemical and protein analyses of CRPC-NE tumors showed upregulation of nuclear-encoded OXPHOS proteins and UPRmt in this lethal subset of prostate cancer suggestive of compensatory upregulation of stress signaling. Genetic deletion and pharmacological inhibition of the main chaperone of UPRmt heat shock protein 60 (HSP60) reduced neuroendocrine prostate cancer (NEPC) growth in vivo as well as reverted NEPC cells to a more epithelial-like state. HSP60-dependent aggressive NEPC phenotypes was associated with upregulation of β-catenin signaling both in cancer cells and in vivo tumors. HSP60 expression rendered enrichment of aggressive prostate cancer signatures and metastatic potential were inhibited upon suppression of UPRmt. We discovered that UPRmt promoted OXPHOS functions including mitochondrial bioenergetics in CRPC-NE via regulation of β-catenin signaling. Mitochondrial biogenesis facilitated cisplatin resistance and inhibition of UPRmt resensitizes CRPC-NE cells to cisplatin. Together, our findings demonstrated that UPRmt promotes mitochondrial health via upregulating β-catenin signaling and UPRmt represents viable therapeutic target for NEPC.

Anticancer therapy-induced peripheral neuropathy in solid tumors: diagnosis, mechanisms, and treatment strategies

Anticancer therapy-induced peripheral neuropathy (PN) is a common adverse event during the diagnosis and treatment of solid tumors. The drug class, cumulative dose, and individual susceptibility affect the incidence and severity of PN. Owing to the lack of specific biomarkers and imaging tests, the diagnostic criteria for PN remain unclear. Moreover, the available and effective clinical treatment strategies are very limited, and most of the current drugs focus on symptom management rather than fundamental reversal of the disease course. The morbidity mechanisms of PN are diverse, including direct neurotoxicity, mitochondrial dysfunction, and disruption of axonal transport. Here, we summarize the diagnosis, mechanisms, and neuroprotective strategies of PN and discuss potential intervention treatments.

Artemisinin alleviates cisplatin-induced damage in GC-1 spermatogonia through ER stress mechanisms

Artemisinin, a compound derived from Artemisia annua, is primarily utilized for malaria treatment. Its mechanism of action involves the rapid and effective inhibition of protein synthesis in malarial parasites. Recently, artemisinin has garnered extensive research attention for its anticancer, antioxidant, and anti-inflammatory properties, as well as its potential role as an adjuvant in cancer treatment. Cisplatin is a commonly used anticancer agent; however, its therapeutic benefits are accompanied by side effects that negatively impact male reproductive function. In this study, the mechanism of the protective effect of artemisinin against cisplatin-induced cytotoxicity was investigated. Type B mouse spermatogonia (GC-1 spg cells), derived from mouse testes, were treated with various concentrations of artemisinin (10-200 μM) to identify the optimal concentration for promoting cell proliferation. Cisplatin induced antiproliferative effects and apoptotic cell death in GC-1 spg cells, whereas the combination of cisplatin and artemisinin restored cell proliferation and reduced apoptosis. Treatment with cisplatin resulted in elevated levels of endoplasmic reticulum (ER) stress-related factors, such as Bip/GRP78, PDI, and Ero1-la, in GC-1 spg cells, while the combination with artemisinin effectively inhibited and reduced these levels. Additionally, cisplatin increased inflammatory markers, including COX2, iNOS, and NF-κB, which were subsequently decreased by artemisinin. This study evaluates artemisinin, a naturally derived compound, as a potential mitigator of side effects on male germ cells during cisplatin-based anticancer treatment. In conclusion, these findings suggest that artemisinin may serve as a supplement or functional agent in cancer therapy.

The Natural Antherea pernyi Sericin Protein Suppresses Gastric Cancer Formation by Inhibiting Cell Proliferation and Inducing Cell Apoptosis

Sericin, a natural macromolecular protein and the main component of silkworm cocoons, exhibits biocompatibility, excellent mechanical properties, and biodegradability. Previous research has confirmed that the sericin protein possesses anticancer properties. Gastric cancer (GC) poses a serious hazard to human health, with a low rate of early diagnosis and a poor prognosis. Investigating the safety and effectiveness of drugs for their used in treatment is imperative. In this study, we confirmed that Antherea pernyi sericin (APS) inhibited the proliferation, migration, and clonal formation of GC cells and caused apoptosis in the cells by regulating the expression of Bcl2 and Bax. Moreover, our data show that APS did not exhibit significant toxicity in normal gastric mucosal cells and mice. Furthermore, the results show that APS suppressed the proliferation of cisplatin-resistant GC cells and promoted cellular apoptosis; however, it had no synergistic effects with cisplatin. All the results indicated that APS exhibits antitumor activity against GC and is a prospective medicinal agent for the clinical treatment of GC, with minimal toxicity and adverse side effects. This research can provide a theoretical basis for sericin in the field of tumor treatment, especially for the application of natural macromolecular polypeptide drugs.

Spatio-temporal transcriptomic analysis reveals distinct nephrotoxicity, DNA damage, and regeneration response after cisplatin

Nephrotoxicity caused by drug or chemical exposure involves complex mechanisms as well as a temporal integration of injury and repair responses in different nephron segments. Distinct cellular transcriptional programs regulate the time-dependent tissue injury and regeneration responses. Whole kidney transcriptome analysis cannot dissect the complex spatio-temporal injury and regeneration responses in the different nephron segments. Here, we used laser capture microdissection of formalin-fixed paraffin embedded sections followed by whole genome targeted RNA-sequencing-TempO-Seq and co-expression gene-network (module) analysis to determine the spatial-temporal responses in rat kidney glomeruli (GM), cortical proximal tubules (CPT) and outer-medulla proximal tubules (OMPT) comparison with whole kidney, after a single dose of the nephrotoxicant cisplatin. We demonstrate that cisplatin induced early onset of DNA damage in both CPT and OMPT, but not GM. Sustained DNA damage response was strongest in OMPT coinciding with OMPT specific inflammatory signaling, actin cytoskeletal remodeling and increased glycolytic metabolism with suppression of mitochondrial activity. Later responses reflected regeneration-related cell cycle pathway activation and ribosomal biogenesis in the injured OMPT regions. Activation of modules containing kidney injury biomarkers was strongest in OMPT, with OMPT Clu expression highly correlating with urinary clusterin biomarker measurements compared the correlation of Kim1. Our findings also showed that whole kidney responses were less sensitive than OMPT. In conclusion, our LCM-TempO-Seq method reveals a detailed spatial mechanistic understanding of renal injury/regeneration after nephrotoxicant exposure and identifies the most representative mechanism-based nephron segment specific renal injury biomarkers.

KRAS mutants confer platinum resistance by regulating ALKBH5 posttranslational modifications in lung cancer

Constitutively active mutations of KRAS are prevalent in non-small cell lung cancer (NSCLC). However, the relationship between these mutations and resistance to platinum-based chemotherapy and the underlying mechanisms remain elusive. In this study, we demonstrate that KRAS mutants confer resistance to platinum in NSCLC. Mechanistically, KRAS mutants mediate platinum resistance in NSCLC cells by activating ERK/JNK signaling, which inhibits AlkB homolog 5 (ALKBH5) N6-methyladenosine (m6A) demethylase activity by regulating posttranslational modifications (PTMs) of ALKBH5. Consequently, the KRAS mutant leads to a global increase in m6A methylation of mRNAs, particularly damage-specific DNA-binding protein 2 (DDB2) and XPC, which are essential for nucleotide excision repair. This methylation stabilized the mRNA of these 2 genes, thus enhancing NSCLC cells' capability to repair platinum-induced DNA damage and avoid apoptosis, thereby contributing to drug resistance. Furthermore, blocking KRAS-mutant-induced m6A methylation, either by overexpressing a SUMOylation-deficient mutant of ALKBH5 or by inhibiting methyltransferase-like 3 (METTL3) pharmacologically, significantly sensitizes KRAS-mutant NSCLC cells to platinum drugs in vitro and in vivo. Collectively, our study uncovers a mechanism that mediates KRAS-mutant-induced chemoresistance in NSCLC cells by activating DNA repair through the modulation of the ERK/JNK/ALKBH5 PTM-induced m6A modification in DNA damage repair-related genes.

Effect of amifostine on apoptotic inflammatory makers in cisplatin induced brain damage in rats

OBJECTIVES

To lessen the negative effects of the medication, we assessed the neuroprotective impact of amifostine nanoparticles against the neurotoxicity generated by cisplatin.

METHODS

60 adult male albino Wistar rats were arranged into six groups. Group 1; received saline intraperitonealy (IP) and served as negative control. Group 2; received IP injection of silica nano-emulsion, Group 3 received cispatin for three consecutive days at the end of the study, Group 4 received amifostine intrapretonealy (IP) before cisplatin injection, Group 5 received silica nano-emulsion alone for one month, group 6 received silica nano-emulsion in combination with cisplatin for three consecutive days at the end of the study. Monocyte chemoattractant protein-1 (MCP-1) and glial fibrillary acidic protein (GFAP) were estimated by ELISA, butrylcholinesterase (BChE) by spectrophotometric method while caspase-3 as a marker of apoptosis by PCR.

RESULTS

The mean levels of brain GFAP, MCP-1, and caspase-3 in the cisplatin group were considerably higher than those in the control group. However, there was a drop in the average level of brain BChE activity. Additionally, the injection of (SiNPs@AMF + cisplatin) increased BChE activities while reducing GFAP, MCP-1, and caspase-3 levels, thereby reversing the negative effects of cisplatin on the brain tissue. On the other hand, the group treated with SiNPs@AMF + cisplatin showed improvement in overall brain structure and minimal pyknotic nuclei and apoptotic neurons were found.

CONCLUSIONS

These outcomes demonstrated amifostine's ability to lessen the histological changes brought on by cisplatin. To sum up, SiNPs@AMF may be a suitable and secure supplemental treatment agent to lessen cisplatin's toxicity in the brain and enhance the treatment's effects throughout chemotherapy.

Mitochondrial respiration in white adipose tissue is dependent on body mass index and tissue location in patients undergoing oncological or parietal digestive surgery

Adipose tissue (AT), is a major endocrine organ that plays a key role in health and disease. However, adipose dysfunctions, especially altered energy metabolism, have been under-investigated as white adipocytes have relatively low mitochondrial density. Nevertheless, recent studies suggest that mitochondria could play a major role in AT disorders and that AT mitochondrial activity could depend on adiposity level and location. This clinical study aimed to evaluate mitochondrial respiration and metabolism in human visceral (vAT) and subcutaneous (scAT) AT and their relationship with body mass index (BMI). This clinical study enrolled 67 patients (30 females/37 males) scheduled for digestive surgery without chemotherapy and parietal infection. BMI ranged from 15.4 to 51.9 kg·m-2 and body composition was estimated by computed tomographic images. Mitochondrial respiration was measured in situ in digitonin-permeabilized AT using high-resolution respirometry and a substrate/inhibitor titration approach. Protein levels of mitochondrial and lipid metabolism key elements were evaluated by Western blot. Maximal mitochondrial respiration correlated negatively with BMI (p < .01) and AT area (p < .001) regardless of the anatomical location. However, oxidative phosphorylation respiration was significantly higher in vAT (2.22 ± 0.15 pmol·sec-1·mg-1) than scAT (1.79 ± 0.17 pmol·sec-1·mg-1) (p < 0.001). In line with oxygraphy results, there were higher levels of mitochondrial respiratory chain complexes in low-BMI patients and vAT. Mitochondrial respiration decreased with increasing BMI in both scAT and vAT, without sex-associated difference. Mitochondrial respiration appeared to be higher in vAT than scAT. These differences were both qualitative and quantitative. Clinical Trials Registration IDNCT05417581.

The chiisanoside derivatives present in the leaves of Acanthopanax sessiliflorus activate autophagy through the LRP6/GSK3β axis and thereafter inhibit oxidative stress, thereby counteracting cisplatin-induced ototoxicity

Introduction

Cisplatin is extensively employed in the treatment of multiple solid malignant tumors. Nevertheless, side effects such as cisplatin-induced ototoxicity (CIO) pose obstacles to tumor therapy.The important natural product chiisanoside from Acanthopanax sessiliflorus has abundant activity against CIO.

Methods

In this study, 26 chiisanoside derivatives were screened, and compound 19 demonstrated significant protective activity against CIO damage. A cisplatin-induced HEI-OC1 cell injury model and a mouse ototoxicity model were established. The regulatory effects were revealed through transcriptome sequencing, and the protein expression levels were analyzed by molecular docking, ELISA, Western blotting, and immunofluorescence.

Results

It was found that compound 19 inhibited cell apoptosis, alleviated abnormal hearing and spiral ganglion damage. Transcriptome sequencing revealed its regulatory effects. Compound 19 treatment increased autophagy levels, thereby alleviating mitochondrial dysfunction and reducing the accumulation of reactive oxygen species (ROS).In-depth studies have found that the autophagy inhibitor 3-methyladenine (3-MA) weakens the regulatory effect of compound 19 on autophagy and inhibits the clearance of damaged cells, resulting in oxidative stress damage, apoptosis and necrosis. By knocking down LRP6, it was found that the protective effect of compound 19 was eliminated, the autophagy level was significantly reduced, oxidative stress and ROS production were induced, and apoptosis after cisplatin exposure was promoted. Finally, the inhibitor LiCl was used to suppress the expression of GSK3β. It was found that inhibiting GSK3β could protect cells from cisplatin-induced damage by activating autophagy.

Discussion

These findings suggest that compound 19 is capable of preventing ototoxicity by activating autophagy via the LRP6/GSK3β axis and consequently inhibiting oxidative stress, offering a new approach for treating CIO and sensorineural hearing loss.

Mitochondrial genome variability and metabolic alterations reveal new biomarkers of resistance in testicular germ cell tumors

Aim: Mutations in the mitochondrial (mt) genome contribute to metabolic dysfunction and their accumulation relates to disease progression and resistance development in cancer cells. This study explores the mutational status of the mt genome of cisplatin-resistant vs. -sensitive testicular germ cell tumor (TGCT) cells and explores its association with their respiration parameters, expression of respiratory genes, and preferences for metabolic pathways to reveal new markers of therapy resistance in TGCTs. Methods: Using Illumina sequencing with Twist Enrichment Panel, the mutations of mt genomes of sensitive 2102EP, H12.1, NTERA-2, T-cam and resistant 2102EP Cis, H12.1 ODM, 1411HP, 1777NRpmet, NTERA-2 Cis and T-cam Cis cell lines were identified. The mt respiration of the cells was assessed using high-resolution respirometry method (O2k-respirometer Oroboros) and the differential expression profiles of mt respiratory genes were determined using RT-qPCR. Associated preferences for metabolic pathways were compared using Glycolysis/OXPHOS assay. Results: In resistant TGCT cells, new mutations in mt genes MT-ND1-6, MT-RNR, MT-CO1-3, MT-ATP6, and MT-CYB were recognized. The respiratory rates of the 1777NRpmet cell line were the highest, while those of the 1411HP line the lowest; rates of the control and all other TGCT cell lines fell between these two lines. The statistically significant differences in gene expression of the respiratory genes were recorded only in NTERA-2 Cis and T-cam Cis cell lines. Sensitive cell lines NTERA-2 and 2102EP preferred oxidative phosphorylation (OXPHOS), while glycolysis was typical for resistant NTERA-2 Cis, 2102EP Cis and 1411HP cell lines. Metastatic 1777NRpmet cells seem to utilize both. An isogenic pair of cell lines H12.1 and H12.1ODM showed the opposite dependence, sensitive H12.1 preferring glycolysis, while resistant H12.1ODM OXPHOS. Conclusion: In summary, our study identified new mutations in mt genes of resistant TGCT cell lines that are associated with different mt respiration parameters, gene expression patterns and preferences for metabolic pathways, providing potential novel molecular biomarkers that distinguish the resistant TGCT phenotype or specify its histological classification.

Ruthenium Drug BOLD-100 Regulates BRAFMT Colorectal Cancer Cell Apoptosis through AhR/ROS/ATR Signaling Axis Modulation

Patients with class I V600EBRAF-mutant (MT) colorectal cancer exhibit a poor prognosis, and their response to combined anti-BRAF/EGFR inhibition remains limited. An unmet need exits for further understanding the biology of V600EBRAFMT colorectal cancer. We used differential gene expression of BRAFWT and MT colorectal cancer cells to identify pathways underpinning BRAFMT colorectal cancer. We tested a panel of molecularly/genetically subtyped colorectal cancer cells for their sensitivity to the unfolded protein response (UPR) activator BOLD-100. To identify novel combination strategies for BOLD-100, we performed RNA sequencing and high-throughput drug screening. Pathway enrichment analysis identified significant enrichment of the UPR and DNA repair pathways in BRAFMT colorectal cancer. We found that oncogenic BRAF plays a crucial role in mediating the response to BOLD-100. Using a systems biology approach, we identified V600EBRAFMT-dependent activation of the replication stress response kinase ataxia telangiectasia and Rad3-related (ATR) as a key mediator of resistance to BOLD-100. Further analysis identified acute increases in BRAFMT-dependent-reactive oxygen species levels following treatment with BOLD-100, which promoted ATR/CHK1 activation and apoptosis. Furthermore, activation of reactive oxygen species/ATR/CHK1 following BOLD-100 was mediated through the AhR transcription factor and CYP1A1. Importantly, pharmacological blockade of this resistance pathway with ATR inhibitors synergistically increased BOLD-100-induced apoptosis and growth inhibition in BRAFMT models. These results highlight a possible novel therapeutic opportunity for BRAFMT colorectal cancer. Implications: BOLD-100 induces BRAFMT-dependent replication stress, and targeted strategies against replication stress (e.g., by using ATR inhibitors) in combination with BOLD-100 may serve as a potential novel therapeutic strategy for clinically aggressive BRAFMT colorectal cancer.

Self-micellizing solid dispersion of thymoquinone with enhanced biopharmaceutical and nephroprotective effects

The present study was designed to develop a self-micellizing solid dispersion (SMSD) containing Thymoquinone (TQM), a phytonutrient obtained from Nigella sativa seeds, aiming to improve its biopharmaceutical and nephroprotective functions. The apparent solubility of TQM in polymer solutions was used to choose an appropriate amphiphilic polymer that could be used to make an SMSD system. Based on the apparent solubility, Soluplus® was selected as an appropriate carrier, and mixing with TQM, SMSD-TQM with different loadings of TQM (5-15%) was made by solvent evaporation and freeze-drying techniques, respectively, and the formulations were optimized. The optimized SMSD-TQM was evaluated in terms of particle size distribution, morphology, release characteristics, pharmacokinetic behavior, and nephroprotective effects in a rat model of acute kidney injury. SMSD-TQM significantly improved the dissolution characteristics (97.8%) of TQM in water within 60 min. Oral administration of SMSD-TQM in rats exhibited a 4.9-fold higher systemic exposure than crystalline TQM. In a cisplatin-induced (6 mg/kg, i.p.) acute kidney-damaged rat model, oral SMSD-TQM (10 mg/kg) improved the nephroprotective effects of TQM based on the results of kidney biomarkers and histological abnormalities. These findings suggest that SMSD-TQM might be efficacious in enhancing the nephroprotective effect of TQM by overcoming biopharmaceutical limitations.

Mechanisms underlying dose-limiting toxicities of conventional chemotherapeutic agents

Dose-limiting toxicities (DLTs) are severe adverse effects that define the maximum tolerated dose of a cancer drug. In addition to the specific mechanisms of each drug, common contributing factors include inflammation, apoptosis, ion imbalances, and tissue-specific enzyme deficiencies. Among various DLTs are bleomycin-induced pulmonary fibrosis, doxorubicin-induced cardiomyopathy, cisplatin-induced nephrotoxicity, methotrexate-induced hepatotoxicity, vincristine-induced neurotoxicity, paclitaxel-induced peripheral neuropathy, and irinotecan, which elicits severe diarrhea. Currently, specific treatments beyond dose reduction are lacking for most toxicities. Further research on cellular and molecular pathways is imperative to improve their management. This review synthesizes preclinical and clinical data on the pharmacological mechanisms underlying DLTs and explores possible treatment approaches. A comprehensive perspective reveals knowledge gaps and emphasizes the need for future studies to develop more targeted strategies for mitigating these dose-dependent adverse effects. This could allow the safer administration of fully efficacious doses to maximize patient survival.

Hesperidin activates Nrf2 to protect cochlear hair cells from cisplatin-induced damage

Cisplatin is widely employed in clinical oncology as an anticancer chemotherapy drug in clinical practice and is known for its severe ototoxic side effects. Prior research indicates that the accumulation of reactive oxygen species (ROS) plays a pivotal role in cisplatin's inner ear toxicity. Hesperidin is a flavanone glycoside extracted from citrus fruits that has anti-inflammatory and antioxidant effects. Nonetheless, the specific pharmacological actions of hesperidin in alleviating cisplatin-induced ototoxicity remain elusive. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is a critical mediator of the cellular oxidative stress response, is influenced by hesperidin. Activation of Nrf2 was shown to have a protective effect against cisplatin-induced ototoxicity. The potential of hesperidin to stimulate Nrf2 in attenuating cisplatin's adverse effects on the inner ear warrants further investigation. This study employs both in vivo and in vitro models of cisplatin ototoxicity to explore this possibility. Our results reveal that hesperidin mitigates cisplatin-induced ototoxicity by activating the Nrf2/NQO1 pathway in sensory hair cells, thereby reducing ROS accumulation, preventing hair cell apoptosis, and alleviating hearing loss.

Machine learning model identifies genetic predictors of cisplatin-induced ototoxicity in CERS6 and TLR4

BACKGROUND

Cisplatin-induced ototoxicity remains a significant concern in pediatric cancer treatment due to its permanent impact on quality of life. Previously, genetic association analyses have been performed to detect genetic variants associated with this adverse reaction.

METHODS

In this study, a combination of interpretable neural networks and Generative Adversarial Networks (GANs) was employed to identify genetic markers associated with cisplatin-induced ototoxicity. The applied method, BRI-Net, incorporates biological domain knowledge to define the network structure and employs adversarial training to learn an unbiased representation of the data, which is robust to known confounders. Leveraging genomic data from a cohort of 362 cisplatin-treated pediatric cancer patients recruited by the CPNDS (Canadian Pharmacogenomics Network for Drug Safety), this model revealed two statistically significant single nucleotide polymorphisms to be associated with cisplatin-induced ototoxicity.

RESULTS

Two markers within the CERS6 (rs13022792, p-value: 3 × 10-4) and TLR4 (rs10759932, p-value: 7 × 10-4) genes were associated with this cisplatin-induced adverse reaction. CERS6, a ceramide synthase, contributes to elevated ceramide levels, a known initiator of apoptotic signals in mouse models of inner ear hair cells. TLR4, a pattern-recognition protein, initiates inflammation in response to cisplatin, and reduced TLR4 expression has been shown in murine hair cells to confer protection from ototoxicity.

CONCLUSION

Overall, these findings provide a foundation for understanding the genetic landscape of cisplatin-induced ototoxicity, with implications for improving patient care and treatment outcomes.

Harnessing the synergy of nanosecond high-power microwave pulses and cisplatin to increase the induction of apoptosis in cancer cells through the activation of ATR/ATM and intrinsic pathways

The therapeutic application and dose of cisplatin are limited due to its toxicity to normal cells. Therefore, combination treatments might be the solution with a low dose of cisplatin. The combination effect of nanosecond pulsed high-power microwave (HPM) with cisplatin has not been investigated before. In this work, we aimed to investigate and assess the potential synergistic effects and most likely underlying mechanisms resulting from the combination of nanosecond pulsed HPM and cisplatin. Three cancer (SKOV3, H460, and MDA-MB231) and two normal (MRC5 and HGF) cell lines underwent separate treatments with HPM and cisplatin, as well as a combined treatment. A higher reduction of viability was observed in cancer cells using combination treatments following 24-h incubation. Cell death, membrane permeability, and intracellular reactive oxygen species (ROS) levels exhibit a noteworthy increase in response to combined 60 pulses of HPM (HPM60) and cisplatin (0.5 μM) treatments compared to control and individual treatments. Elevated γ-H2AX levels indicate DNA double-strand breaks in combined treatments. Additionally, upregulation of ATR/ATM, Chk1/Chk2, P53, and caspase 3/8, Bax, PARP, and Bcl2 confirms DNA damage and mitochondrial dysfunction, leading to apoptosis. Remarkably, half maximal inhibitory concentration (IC50) results showed that HPM60 and cisplatin (0.5 μM) resulted in 16 times higher cell death in SKOV3 and H460 cells compared to cisplatin alone. Moreover, the efficacy of this combined treatment led to an over 50 % decrease in the viability of cancer cells. On the other hand, normal cells (MRC5 and HGF) exhibited only a minor 3-5 % decrease in viability under the same treatment conditions. The obtained results elucidate the cellular mechanisms driving cell apoptosis/death, offering insights for potential advancements in cancer therapy through the combined application of nanosecond pulses of HPM and cisplatin. This serves as a first step for future investigations in this domain.

Cisplatin induces kidney damage through the down-regulation of Prx I by autophagic degradation

In this study, we investigated the potential role of PrxI in cis-diamminedichloroplatinum (cisplatin)-induced renal damage in mice. The anticancer drug cisplatin is a chemotherapeutic agent that is widely used to treat solid tumors. Cisplatin-induced nephrotoxicity is a serious dose-limiting side effect, primarily caused by oxidative stress. The oxidative stress further damages DNA, membranes, and mitochondria, and increases endoplasmic reticulum (ER) stress. Cisplatin produces reactive oxygen species (ROS) through Cytochrome P450 2E1 (CYP2E1) and localizes to the surface of the ER, where CYP2E1 is located. Among the six Prx isoforms, Prx I was selectively degraded in cisplatin-treated kidneys during severe renal function damage. Prx I degradation is blocked in mouse proximal tubular cells treated with 3-methyladenine, an autophagy inhibitor, and in MEF lacking ATG7. Moreover, increased ROS levels on the ER surface due to CYP2E1 overexpression further accelerated Prx I degradation. These results suggest that Prx I degradation is largely mediated through autophagy, which is promoted by cisplatin-induced ER stress. Ablation of Prx I exacerbated cisplatin-induced nephrotoxicity and significantly increased the abundance of oxidative stress, ER stress, and inflammatory markers in the kidney, indicating that Prx I plays a protective role against cisplatin-induced nephrotoxicity.

Synergistic anticancer activity of resveratrol with cisplatin and carboplatin in A549 lung adenocarcinoma cells

BACKGROUND

This study looked at the efficacy of combining the phytochemical resveratrol with the anticancer drugs cisplatin and carboplatin on lung adenocarcinoma cell lines.

MATERIALS AND METHODS

We used MTT assay and generation of Reactive Oxygen Species levels using molecular fluorogenic probe 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) to investigate the effects of resveratrol in combination with cisplatin and carboplatin on the proliferation and viability of cells and levels of reactive oxygen species (ROS).

RESULTS

Resveratrol has an anti-proliferative effect on A549 lung cancer cells, inhibiting cell proliferation in a dose and time-dependent manner. Resveratrol in conjunction with cisplatin and carboplatin inhibited cell proliferation synergistically. The combination therapy of cisplatin and carboplatin with Resveratrol showed enhanced growth inhibition of lung cancer cells in in-vitro with IC50 values of 15.09 ± 0.71 µM and IC50 values of 21.72 ± 1.9 µM, respectively. The present investigation also revealed the significant dose-dependent ROS generation in A549 cells by cisplatin, carboplatin, and their combination with resveratrol. Carboplatin treatment in combination with Resveratrol induced a higher generation of ROS (3.4-fold) when compared to carboplatin treatment (2.4-fold) at the highest concentration.

CONCLUSIONS

Our findings offered a basis for further research for assessing the potential of Resveratrol as a therapeutic agent to treat lung adenocarcinoma and whether it can be used as an adjuvant with drugs like cisplatin and carboplatin for improving their efficacies. However, the underlying processes of cell inhibition and cell death should be thoroughly investigated.

1,3-Disubstituted thiourea derivatives: Promising candidates for medicinal applications with enhanced cytotoxic effects on cancer cells

The distinct chemical structure of thiourea derivatives provides them with an advantage in selectively targeting cancer cells. In our previous study, we selected the most potent compounds, 2 and 8, with 3,4-dichloro- and 3-trifluoromethylphenyl substituents, respectively, across colorectal (SW480 and SW620), prostate (PC3), and leukemia (K-562) cancer cell lines, as well as non-tumor HaCaT cells. Our research has demonstrated their anticancer potential by targeting key molecular pathways involved in cancer progression, including caspase 3/7 activation, NF-κB (Nuclear Factor Kappa-light-chain-enhancer of activated B cells) activation decrease, VEGF (Vascular Endothelial Growth Factor) secretion, ROS (Reactive Oxygen Species) production, and metabolite profile alterations. Notably, these processes exhibited no significant alterations in HaCaT cells. The effectiveness of the studied compounds was also tested on spheroids (3D culture). Both derivatives 2 and 8 increased caspase activity, decreased ROS production and NF-κB activation, and suppressed the release of VEGF in cancer cells. Metabolomic analysis revealed intriguing shifts in cancer cell metabolic profiles, particularly in lipids and pyrimidines metabolism. Assessment of cell viability in 3D spheroids showed that SW620 cells exhibited better sensitivity to compound 2 than 8. In summary, structural modifications of the thiourea terminal components, particularly dihalogenophenyl derivative 2 and para-substituted analog 8, demonstrate their potential as anticancer agents while preserving safety for normal cells.

MitoTam induces ferroptosis and increases radiosensitivity in head and neck cancer cells

BACKGROUND AND PURPOSE

Radiotherapy (RT) is an integral treatment part for patients with head and neck squamous cell carcinoma (HNSCC), but radioresistance remains a major issue. Here, we use MitoTam, a mitochondrially targeted analogue of tamoxifen, which we aim to stimulate ferroptotic cell death with, and sensitize radioresistant cells to RT.

MATERIALS AND METHODS

We assessed viability, reactive oxygen species (ROS) production, disruption of mitochondrial membrane potential, and lipid peroxidation in radiosensitive (UT-SCC-40) and radioresistant (UT-SCC-5) HNSCC cells following MitoTam treatment. To assess ferroptosis specificity, we used the ferroptosis inhibitor ferrostatin-1 (fer-1). Also, total antioxidant capacity and sensitivity to tert-butyl hydroperoxide were evaluated to assess ROS-responses. 53BP1 staining was used to assess radiosensitivity after MitoTam treatment.

RESULTS

Our data revealed increased ROS, cell death, disruption of mitochondrial membrane potential, and lipid peroxidation following MitoTam treatment in both cell lines. Adverse effects of MitoTam on cell death, membrane potential and lipid peroxidation were prevented by fer-1, indicating induction of ferroptosis. Radioresistant HNSCC cells were less sensitive to the effects of MitoTam due to intrinsic higher antioxidant capacity. MitoTam treatment prior to RT led to superadditive residual DNA damage expressed by 53BP1 foci compared to RT or MitoTam alone.

CONCLUSION

MitoTam induced ferroptosis in HNSCC cells, which could be used to overcome the elevated antioxidant capacity of radioresistant cells and sensitize such cells to RT. Treatment with MitoTam followed by RT could therefore present a promising effective therapy of radioresistant cancers.

STATEMENT OF SIGNIFICANCE

Radiotherapy is applied in the treatment of a majority of cancer patients. Radioresistance due to elevated antioxidant levels can be overcome by promoting ferroptotic cell death combining ROS-inducing drug MitoTam with radiotherapy.

Pharmacokinetic predictions of ROS-mediated targets and genotoxin combinations via multiple ligand simultaneous docking and ROS evaluation in vitro using HepG2 cell lines

Although combination therapy is known for its high efficacy, reduced side effects and drug resistance, toxicity remains a major drawback. Some of the genes are likely to induce hepatotoxicity through ROS-mediated mechanisms when a drug is metabolized alone or in combination in the liver. To address this, we have developed a scientific approach to predict the toxicity of different genotoxin combinations and validate their interactions with various targets. The current study is an extensive study of our previous set of in vivo rat liver microarray data processed using R studio for their functional analysis. About five combinations of genotoxins such as CPT/ETP, CPT/CPL, ETP/CPL, CP/CPT and EES/CP along with their differential gene expression targeting Chemical carcinogenesis-ROS are chosen for this study. We aim to examine the binding affinity of different genotoxin combinations using in silico multiple ligand simultaneous docking (MLSD) and are then bio-evaluated for cytotoxicity in vitro using human hepatocellular carcinoma cell lines (HepG2) with the MTT assay. As a result, dose-response cytotoxicity with its strength of interactions and a significant variance in ROS levels in the treated cells is observed compared to their IC50 values. Out of 5 combinations such as CPT/CPL, ETP/CPL and EES/CP are found not only to be significantly cytotoxic but also induce oxidative stress specifically above their IC50 values with good and moderate binding interactions ensuring their toxicity. On the contrary, the safe combinations are found to be CTP/ETP and CP/CPT possibly with no and tolerable adverse effects standing as preliminary information for researchers in drug design and development.

Targeting mitochondria: a novel approach for treating platinum-resistant ovarian cancer

Ovarian cancer is a prevalent gynecologic malignancy with the second-highest mortality rate among gynecologic malignancies. Platinum-based chemotherapy is the first-line treatment for ovarian cancer; however, a majority of patients with ovarian cancer experience relapse and develop platinum resistance following initial treatment. Despite extensive research on the mechanisms of platinum resistance at the nuclear level, the issue of platinum resistance in ovarian cancer remains largely unresolved. It is noteworthy that mitochondrial DNA (mtDNA) exhibits higher affinity for platinum compared to nuclear DNA (nDNA). Mutations in mtDNA can modulate tumor chemosensitivity through various mechanisms, including DNA damage responses, shifts in energy metabolism, maintenance of Reactive Oxygen Species (ROS) homeostasis, and alterations in mitochondrial dynamics. Concurrently, retrograde signals produced by mtDNA mutations and their subsequent cascades establish communication with the nucleus, leading to the reorganization of the nuclear transcriptome and governing the transcription of genes and signaling pathways associated with chemoresistance. Furthermore, mitochondrial translocation among cells emerges as a crucial factor influencing the effectiveness of chemotherapy in ovarian cancer. This review aims to explore the role and mechanism of mitochondria in platinum resistance, with a specific focus on mtDNA mutations and the resulting metabolic reprogramming, ROS regulation, changes in mitochondrial dynamics, mitochondria-nucleus communication, and mitochondrial transfer.

Reactive oxygen species from non-thermal gas plasma (CAP): implication for targeting cancer stem cells

Cancer remains a major global health challenge, with the persistence of cancer stem cells (CSCs) contributing to treatment resistance and relapse. Despite advancements in cancer therapy, targeting CSCs presents a significant hurdle. Non-thermal gas plasma, also known as CAP, represents an innovative cancer treatment. It has recently gained attention for its often found to be selective, immunogenic, and potent anti-cancer properties. CAP is composed of a collection of transient, high-energy, and physically and chemically active entities, such as reactive oxygen species (ROS). It is acknowledged that the latter are responsible for a major portion of biomedical CAP effects. The dynamic interplay of CAP-derived ROS and other components contributes to the unique and versatile properties of CAP, enabling it to interact with biological systems and elicit various therapeutic effects, including its potential in cancer treatment. While CAP has shown promise in various cancer types, its application against CSCs is relatively unexplored. This review assesses the potential of CAP as a therapeutic strategy for targeting CSCs, focusing on its ability to regulate cellular states and achieve redox homeostasis. This is done by providing an overview of CSC characteristics and demonstrating recent findings on CAP's efficacy in targeting these cells. By contributing insights into the unique attributes of CSCs and the potential of CAP, this work contributes to an advanced understanding of innovative oncology strategies.

Potential role of heteroplasmic mitochondrial DNA mutations in modulating the subtype-specific adaptation of oral squamous cell carcinoma to cisplatin therapy

Cancer cells are constantly evolving to adapt to environmental changes, particularly during exposure to drug treatment. In this work, we aimed to characterize genetic and epigenetic changes in mitochondrial DNA (mtDNA) that may increase the resistance of oral squamous cell carcinoma (OSCC) to cisplatin. We first derived drug-resistant cells from two human OSCC cell lines, namely SAS and H103, by continual cisplatin treatments for about 4 months. To determine mtDNA changes induced by cisplatin, we performed nanopore sequencing and quantitative polymerase chain reaction analysis of mtDNA extracted from the cells pre- and post-treatment. We also assessed the mitochondrial functions of the cells and their capacity to generate intracellular reactive oxygen species (ROS). We found that in the cisplatin-resistant cells derived from SAS, there was a reduction in mtDNA content and significant enrichment of a m.3910G > C mutation in the MT-ND1 gene. However, such changes were not detected in cisplatin-resistant H103 cells. The cisplatin treatment also altered methylation patterns in both SAS and H103 cells and decreased their sensitivity to ROS-induced cytotoxicity. We suggest that the sequence alterations and epigenetic changes in mtDNA and the reduction in mtDNA content could be key drivers of cisplatin resistance in OSCC. These mtDNA alterations may participate in cellular adaptation that serves as a response to adverse changes in the environment, particularly exposure to cytotoxic agents. Importantly, the observed mtDNA changes may be influenced by the distinct genetic landscapes of various cancer subtypes. Overall, this study reveals significant insights into cisplatin resistance driven by complex mtDNA dynamics, particularly in OSCC. This underscores the need for targeted therapies tailored to the genetic profiles of individual OSCC patients to improve disease prognosis.

Direct targeting of mitochondria by cisplatin leads to cytotoxicity in zebrafish lateral-line hair cells

Cisplatin is a chemotherapy drug that causes permanent hearing loss by injuring cochlear hair cells. Hair cell mitochondria have emerged as potential mediators of hair cell cytotoxicity. Using in vivo live imaging of hair cells in the zebrafish lateral-line organ expressing a genetically encoded indicator of cumulative mitochondrial activity, we first demonstrate that greater redox history increases susceptibility to cisplatin. Next, we conducted time-lapse imaging to understand dynamic changes in mitochondrial homeostasis and observe elevated mitochondrial and cytosolic calcium that surge prior to hair cell death. Furthermore, using a localized probe that fluoresces in the presence of cisplatin, we show that cisplatin directly accumulates in hair cell mitochondria, and this accumulation occurs before mitochondrial dysregulation and apoptosis. Our findings provide evidence that cisplatin directly targets hair cell mitochondria and support that the mitochondria are integral to cisplatin cytotoxicity in hair cells.

Nano Spirulina platensis countered cisplatin-induced repro-toxicity by reversing the expression of altered steroid hormones and downregulation of the StAR gene

Cisplatin is a commonly utilized chemotherapy medication for treating different sarcomas and carcinomas. Its ability interferes with cancer cells' DNA repair pathways and postpones unfavorable outcomes in cancer patients. The current investigation's goal was to ascertain if nano Spirulina platensis (NSP) might shield rat testicles from cisplatin damage by assessing the expression of the StAR and SOD genes, sex hormones, 17ß-hydroxysteroid dehydrogenase(17ß-HSD), sperm profile picture, oxidative condition of testes, testicular histology, and DNA damage. Four equal and random groups of 28 adult male Wistar rats were created; the control group was given saline for 8 weeks. An extraction of NSP at a concentration of 2500 mg/kg body weight was administered orally for 8 weeks to the NSP group. For the first 4 weeks, the cisplatin group was intraperitoneally injected with 2 mg/kg/body weight of cisplatin, and for the next 4 weeks, they were given a dosage of 4 mg/kg/body weight. The cisplatin + NSP group was given both NSP and cisplatin. The results of the experiment showed that intake of NSP and cisplatin improved sperm profile; re-established the balance of oxidizing agents and antioxidant state; enhanced testicular histology; promoted the histometric parameters of seminiferous tubules including epithelial height, their diameter, and Johnsen's score, decreasing DNA breakage in testicular tissue; increased testosterone level; decreased 17ß-HSD concentration; and upregulated both the StAR and SOD gene expression in testicles compared to rats exposed to cisplatin alone. These results demonstrate that NSP is a promising agent for improving cisplatin-induced testicular injury and infertility.

Leveraging large-scale datasets and single cell omics data to develop a polygenic score for cisplatin-induced ototoxicity

BACKGROUND

Cisplatin-induced ototoxicity (CIO), characterized by irreversible and progressive bilateral hearing loss, is a prevalent adverse effect of cisplatin chemotherapy. Alongside clinical risk factors, genetic variants contribute to CIO and genome-wide association studies (GWAS) have highlighted the polygenicity of this adverse drug reaction. Polygenic scores (PGS), which integrate information from multiple genetic variants across the genome, offer a promising tool for the identification of individuals who are at higher risk for CIO. Integrating large-scale hearing loss GWAS data with single cell omics data holds potential to overcome limitations related to small sample sizes associated with CIO studies, enabling the creation of PGSs to predict CIO risk.

RESULTS

We utilized a large-scale hearing loss GWAS and murine inner ear single nuclei RNA-sequencing (snRNA-seq) data to develop two polygenic scores: a hearing loss PGS (PGSHL) and a biologically informed PGS for CIO (PGSCIO). The PGSCIO included only variants which mapped to genes that were differentially expressed within cochlear cells that showed differential abundance in the murine snRNA-seq data post-cisplatin treatment. Evaluation of the association of these PGSs with CIO in our target CIO cohort revealed that PGSCIO demonstrated superior performance (P = 5.54 × 10- 5) relative to PGSHL (P = 2.93 × 10- 3). PGSCIO was also associated with CIO in our test cohort (P = 0.04), while the PGSHL did not show a significant association with CIO (P = 0.52).

CONCLUSION

This study developed the first PGS for CIO using a large-scale hearing loss dataset and a biologically informed filter generated from cisplatin-treated murine inner ear snRNA-seq data. This innovative approach offers new avenues for developing PGSs for pharmacogenomic traits, which could contribute to the implementation of tailored therapeutic interventions. Further, our approach facilitated the identification of specific cochlear cells that may play critical roles in CIO. These novel insights will guide future research aimed at developing targeted therapeutic strategies to prevent CIO.

HEBP2 affects sensitivity to cisplatin and BCNU but not to paclitaxel in MDA-MB-231 breast cancer cells

Breast cancer has the highest incidence of all cancer types in women. Triple-negative breast cancer (TNBC) accounts for 15% of all breast cancer cases and is the most aggressive type, with a poor prognosis and limited treatment. Treatment failure in patients is largely due to resistance to chemotherapy. In this study, we aimed to identify the novel factors contributing to chemoresistance in TNBC using cisplatin and 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). We found that transactivation of the heme-binding protein 2 (HEBP2) gene was common in surviving colonies of cells after exposure to two types of chemotherapeutic agents, namely cisplatin and BCNU, from genome-scale transcriptional activation library screening in the TNBC cell line MDA-MB-231. Analysis of a public database (Proteogenomic Landscape of Breast Cancer, CPTAC) indicated that HEBP2 mRNA expression was elevated in TNBC tissues compared to that in non-TNBC tissues. HEBP2 facilitates necrotic cell death under oxidative stress; however, it is not yet known whether HEBP2 affects cancer cell survival following chemotherapy. Therefore, we investigated the effects of HEBP2 expression on the sensitivity to cisplatin and BCNU in MDA-MB-231 cells. Overexpression of HEBP2 significantly enhanced the viability of MDA-MB-231 cells in response to cisplatin and BCNU, but not methyl methanesulfonate (MMS) and paclitaxel. In contrast, CRISPR/Cas9-mediated HEBP2-knockout greatly reduced cell viability in response to cisplatin and BCNU, but not to MMS and paclitaxel, in MDA-MB-231 cells. Moreover, the exogenous introduction of HEBP2 restored the resistance of HEBP2-deficient cells to cisplatin and BCNU to wild-type levels. These findings suggest that HEBP2 may play a significant role in resistance to cisplatin and BCNU, which induce intrastrand and interstrand DNA crosslinks, but not to monoalkylating or microtubule-stabilizing agents in TNBC cells. The possibility exists that HEBP2 serves as a biomarker for predicting response or a therapeutic target for overcoming resistance to platinum-based and alkylating anticancer agents in TNBC.

Unravelling biochemical responses in the species Mytilus galloprovincialis exposed to the antineoplastics ifosfamide and cisplatin under different temperature scenarios

This study investigates the chronic impact of two of the most widely consumed antineoplastic drugs, Ifosfamide (IF) and Cisplatin (CDDP), on the bivalve species Mytilus galloprovincialis under current (17 °C) and predicted warming conditions (21 °C). Accompanying the expected increase in worldwide cancer incidence, antineoplastics detection in the aquatic environment is also expected to rise. Mussels were exposed to varying concentrations of IF (10, 100, 500 ng/L) and CDDP (10, 100, 1000 ng/L) for 28 days. Biochemical analyses focused on metabolic, antioxidant and biotransformation capacities, cellular damage, and neurotoxicity. Results showed temperature-dependent variations in biochemical responses. Metabolic capacity remained stable in mussels exposed to IF, while CDDP exposure increased it at 1000 ng/L for both temperatures. Antioxidant enzyme activities were unaffected by IF, but CDDP activated them, particularly at 21 °C. Biotransformation capacity was unchanged by IF but enhanced by CDDP. Nevertheless, cellular damage occurred at CDDP concentrations above 100 ng/L, regardless of temperature. Integrated biomarker responses highlighted CDDP's greater impact, emphasizing the critical role of temperature in shaping organismal responses and underscoring the complexity of environmental stressor interactions.

Resveratrol shields against cisplatin-induced ototoxicity through epigenetic lncRNA GAS5 modulation of miR-455-5p/PTEN pathway

BACKGROUND

Our previous research demonstrated that resveratrol counters DDP-induced ototoxicity by upregulating miR-455-5p, which targets PTEN. This study aimed to elucidate the underlying mechanisms involving GAS5 and DNA methyltransferase 1 (DNMT1) in resveratrol's protective action.

METHODS

A luciferase reporter assay and RNA immunoprecipitation (RIP) assay were employed to study the binding between GAS5 and miR-455-5p, as well as between miR-455-5p and PTEN. HEI-OC1 cells treated with DDP were transfected with vectors for GAS5, si-GAS5, DNMT1, si-DNMT1, and miR-455-5p mimics, as well as PTEN. Subsequently, they were treated with resveratrol and exposed to DDP, both separately and in combination. The distribution of CpG islands in the GAS5 promoter was identified using MethyPrimer, and methylation-specific PCR (MSP) was conducted to determine the methylation levels of GAS5. Chromatin immunoprecipitation (ChIP) was utilized to examine the interaction between DNMT1 and GAS5. The viability of HEI-OC1 cells, catalase (CAT) activity, apoptosis, and ROS levels were assessed using the CCK-8 assay, CAT assay, TUNEL staining, and flow cytometry, respectively. An in vivo mouse model was developed to measure auditory brainstem response (ABR) thresholds, while RT-qPCR and Western blot analysis were employed to evaluate molecular levels.

RESULTS

Our study discovered that GAS5 acts as a sponge for miR-455-5p, thereby increasing PTEN expression in DDP-treated HEI-OC1 cells. This process was reversed upon treatment with resveratrol. Importantly, DNMT1 promoted the methylation of the GAS5 promoter, leading to the suppression of GAS5 expression. This suppression enhanced the effectiveness of resveratrol in combating DDP-induced apoptosis and ROS in HEI-OC1 cells and amplified its protective effect against DDP's ototoxicity in vivo.

CONCLUSIONS

Our research emphasizes the significance of the DNMT1/GAS5/miR-455-5p/PTEN axis as a promising new route to boost resveratrol's effectiveness against DDP-induced ototoxicity.

Histamine deficiency exacerbates cisplatin-induced ferroptosis in cochlea hair cells of HDC knockout mice

Cisplatin (CDDP) is extensively utilized in the management of diverse types of cancers, but its ototoxicity cannot be ignored, and clinical interventions are not ideal. Histidine decarboxylase (HDC) is the exclusive enzyme for histamine synthesis. Anti-histamine receptor drugs are ubiquitously employed in the therapeutics of allergies and gastrointestinal diseases. Yet, the specific role of histamine and its signaling in the inner ear is not fully understood. This study utilized cisplatin treated mice and HEI-OC1 auditory hair cell line to establish a cisplatin-induced ototoxicity (CIO) model. Histidine decarboxylase knockout (HDC-/-) mice and histamine receptor 1 (H1R) antagonist were utilized to investigate the influence of HDC/histamine/H1R signaling on ototoxicity. The results identified HDC and H1R expression in mouse hair cells. Transcriptomics indicated that the expression levels of oxidative stress-related genes in the cochlea of HDC-/- mice increased. Furthermore, histamine deficiency or suppression of H1R signaling accelerated HC ferroptosis, a pivotal factor underlying the aggravation of CIO in vivo and in vitro, conversely, the supplementation of exogenous histamine reversed these deleterious effects. Mechanistically, this study revealed that the malfunction of HDC/histamine/H1R signaling induced upregulation of NRF2 expression, accompanied by the upregulation of ACSL4 and downregulation of GPX4 expression, which are major regulatory factors of ferroptosis. In summary, histamine deficiency may induce hair cell death by regulating the H1R pathway and exacerbate CIO. Our findings have indicated a potential therapeutic target for CIO.

Cisplatin Resistance and Metabolism: Simplification of Complexity

Cisplatin is one of the most well-known anti-cancer drugs and has demonstrated efficacy against numerous tumor types for many decades. However, a key challenge with cisplatin, as with any chemotherapeutic agent, is the development of resistance with a resultant loss of efficacy. This resistance is often associated with metabolic alterations that allow insensitive cells to divide and survive under treatment. These adaptations could vary greatly among different tumor types and may seem questionable and incomprehensible at first glance. Here we discuss the disturbances in glucose, lipid, and amino acid metabolism in cisplatin-resistant cells as well as the roles of ferroptosis and autophagy in acquiring this type of drug intolerance.

Evaluation of cytotoxic effect of siphonochilone from African ginger: an in vitro analysis

Plants provide a wide array of compounds that can be explored for potential anticancer properties. Siphonochilone, a furanoterpene that represents one of the main components of the African plant Siphonochilus aethiopicus, shows numerous health benefits. However, to date, its antiproliferative properties have not been tested. The aim of this study was to analyze the cytotoxic effects of siphonochilone on a panel of cancer cell lines and its underlying mechanism of action. Our results demonstrated that siphonochilone exhibited significant cytotoxic effects on pancreatic, breast, lung, colon, and liver cancer cell lines showing a IC50 ranging from 22 to 124 μM at 72 h of treatment and highlighting its cytotoxic effect against MCF7 and PANC1 breast and pancreas cancer cell lines (22.03 and 39.03 μM, respectively). Cell death in these tumor lines was mediated by apoptosis by the mitochondrial pathway, as evidenced by siphonochilone-induced depolarization of the mitochondrial membrane potential. In addition, siphonochilone treatment involves the generation of reactive oxygen species that may contribute to apoptosis induction. In this work, we described for the first time the cytotoxic properties of siphonochilone and provided data about the molecular processes of cell death. Although future studies will be necessary, our results support the interest in this molecule in relation to their clinical application in cancer, and especially in breast and pancreatic cancer.

DSB-induced oxidative stress: Uncovering crosstalk between DNA damage response and cellular metabolism

While that ROS causes DNA damage is well documented, there has been limited investigation into whether DNA damages and their repair processes can conversely induce oxidative stress. By generating a site-specific DNA double strand break (DSB) via I-SceI endonuclease expression in S. cerevisiae without damaging other cellular components, this study demonstrated that DNA repair does trigger oxidative stress. Deleting genes participating in the initiation of the resection step of homologous recombination (HR), like the MRX complex, resulted in stimulation of ROS. In contrast, deleting genes acting downstream of HR resection suppressed ROS levels. Additionally, blocking non-homologous end joining (NHEJ) also suppressed ROS. Further analysis identified Rad53 as a key player that relays DNA damage signals to alter redox metabolism in an HR-specific manner. These results suggest both HR and NHEJ can drive metabolism changes and oxidative stress, with NHEJ playing a more prominent role in ROS stimulation. Further analysis revealed a correlation between DSB-induced ROS increase and enhanced activity of NADPH oxidase Yno1 and various antioxidant enzymes. Deleting the antioxidant gene SOD1 induced synthetic lethality in HR-deficient mutants like mre11Δ and rad51Δ upon DSB induction. These findings uncover a significant interplay between DNA repair mechanisms and cellular metabolism, providing insights into understanding the side effects of genotoxic therapies and potentially aiding development of more effective cancer treatment strategies.

Enhancing ovarian cancer treatment with maleimide-modified Pt(IV) prodrug nanoparticles

The limitations of platinum in ovarian cancer therapy, such as poor solubility and significant side effects, often lead to suboptimal therapeutic outcome and mortality. In this study, we have developed a novel approach utilizing biodegradable polymeric nanoparticles as a drug delivery system (NDDS), loaded with advanced platinum (IV) (Pt(IV)) prodrugs. A key feature of our approach is the enhancement of nanoparticles with maleimide, a modification hypothesized to significantly boost tumor tissue accumulation. When tested in mouse models of orthotopic and peritoneal metastasis ovarian cancer, these maleimide-modified nanoparticles are anticipated to show preferential accumulation in tumor tissues, enhancing therapeutic efficiency and minimizing systemic drug exposure. Our findings demonstrate that the maleimide-modified Pt(IV)-loaded NDDSs significantly reduce tumor burden in comparison to traditional cisplatin therapy, while simultaneously reducing adverse side effects. This leads to markedly improved survival rates in models of peritoneal metastasis ovarian cancer, offering a promising new direction in the treatment of this challenging disease.

Is There a Mitochondrial Protection via Remote Ischemic Conditioning in Settings of Anticancer Therapy Cardiotoxicity?

PURPOSE OF REVIEW

To provide an overview of (a) protective effects on mitochondria induced by remote ischemic conditioning (RIC) and (b) mitochondrial damage caused by anticancer therapy. We then discuss the available results of studies on mitochondrial protection via RIC in anticancer therapy-induced cardiotoxicity.

RECENT FINDINGS

In three experimental studies in healthy mice and pigs, there was a RIC-mediated protection against anthracycline-induced cardiotoxicity and there was some evidence of improved mitochondrial function with RIC. The RIC-mediated protection was not confirmed in the two available studies in cancer patients. In adult cancer patients, RIC was associated with an adverse outcome. There are no data on mitochondrial function in cancer patients. Studies in tumor-bearing animals are needed to determine whether RIC does not interfere with the anticancer properties of the drugs and whether RIC actually improves mitochondrial function, ultimately resulting in improved cardiac function.

Metabolic profiling and combined therapeutic strategies unveil the cytotoxic potential of selenium-chrysin (SeChry) in NSCLC cells

Lung cancer ranks as the predominant cause of cancer-related mortalities on a global scale. Despite progress in therapeutic interventions, encompassing surgical procedures, radiation, chemotherapy, targeted therapies and immunotherapy, the overall prognosis remains unfavorable. Imbalances in redox equilibrium and disrupted redox signaling, common traits in tumors, play crucial roles in malignant progression and treatment resistance. Cancer cells, often characterized by persistent high levels of reactive oxygen species (ROS) resulting from genetic, metabolic, and microenvironmental alterations, counterbalance this by enhancing their antioxidant capacity. Cysteine availability emerges as a critical factor in chemoresistance, shaping the survival dynamics of non-small cell lung cancer (NSCLC) cells. Selenium-chrysin (SeChry) was disclosed as a modulator of cysteine intracellular availability. This study comprehensively characterizes the metabolism of SeChry and investigates its cytotoxic effects in NSCLC. SeChry treatment induces notable metabolic shifts, particularly in selenocompound metabolism, impacting crucial pathways such as glycolysis, gluconeogenesis, the tricarboxylic acid (TCA) cycle, and amino acid metabolism. Additionally, SeChry affects the levels of key metabolites such as acetate, lactate, glucose, and amino acids, contributing to disruptions in redox homeostasis and cellular biosynthesis. The combination of SeChry with other treatments, such as glycolysis inhibition and chemotherapy, results in greater efficacy. Furthermore, by exploiting NSCLC's capacity to consume lactate, the use of lactic acid-conjugated dendrimer nanoparticles for SeChry delivery is investigated, showing specificity to cancer cells expressing monocarboxylate transporters.

Cisplatin drives mitochondrial dysregulation in sensory hair cells

Cisplatin is a chemotherapy drug that causes permanent hearing loss by injuring cochlear hair cells. The mechanisms that initiate injury are not fully understood, but mitochondria have emerged as potential mediators of hair cell cytotoxicity. Using in vivo live imaging of hair cells in the zebrafish lateral-line organ expressing a genetically encoded indicator of cumulative mitochondrial activity, we first demonstrate that greater redox history increases susceptibility to cisplatin. Next, we conducted time-lapse imaging to understand dynamic changes in mitochondrial homeostasis and observe elevated mitochondrial and cytosolic calcium that surge prior to hair cell death. Furthermore, using a localized probe that fluoresces in the presence of cisplatin, we show that cisplatin directly accumulates in hair cell mitochondria, and this accumulation occurs before mitochondrial dysregulation and apoptosis. Our findings provide evidence that cisplatin directly targets hair cell mitochondria and support that the mitochondria are integral to cisplatin cytotoxicity in hair cells.

Effects of protocatechuic acid against cisplatin-induced neurotoxicity in rat brains: an experimental study

Aims/Objectives: Cisplatin (CIS) is widely used in the treatment of various malignant tumors. The aim of study is to determine the potential protective effects of protocatechuic acid (PCA) on the brain in neurotoxicity induced by CIS in rats.Materials and methods: Forty rats were divided into four groups: 1-Control group: 2- PCA group: PCA was administered orally at a dose of 100 mg/kg/day for 5 weeks. 3-CIS group: 5 mg/kg/week of CIS was administered intraperiteonally 4-PCA + CIS group: The rats were given PCA orally daily for 5 weeks and CIS of 5 mg/kg/week. The brain tissues were used for histopathological examinations and for total antioxidant capacity (TAC), total oxidative state (TOS), oxidative stress index (OSI), tumornecrosis factor-alpha (T NF-α), interleukin 6 (IL-6) Interleukin 1 beta (IL-1β), acetylcholinesterase (AChE), glutamate, gamma aminobutyric acid (GABA), dopamine analyzes in ELISA. WBC, RBC, hemoglobin and hematocrit levels were measured.Results: PCA + CIS group compared to CIS group TOS, OSI, T NF-α, IL-6, IL-1β, AChE, glutamate, WBC levels decreased significantly, while TAC and GABA levels increased statistically significant. With this study, P CA corrected the deterioration in the oxidant / antioxidant status, suppressed neuro-inflammation, decreased AChE activity, partially normalized neurotransmitters, and decreased the increased WBC count. Necrosis seen in the CIS group in histopathological examinations was never seen in the PCA + CIS group.Conclusions: PCA may provide therapeutic benefit when used in conjunction with CIS.

Efficacy and Mechanisms of Antioxidant Compounds and Combinations Thereof against Cisplatin-Induced Hearing Loss in a Rat Model

Cisplatin is an election chemotherapeutic agent used for many cancer treatments. Its cytotoxicity against neoplastic cells is mirrored by that taking place in healthy cells and tissues, resulting in serious adverse events. A very frequent one is ototoxicity, causing hearing loss which may permanently affect quality of life after successful oncologic treatments. Exacerbated oxidative stress is a main cytotoxic mechanism of cisplatin, including ototoxicity. Previous reports have shown antioxidant protection against cisplatin ototoxicity, but there is a lack of comparative studies on the otoprotectant activity and mechanism of antioxidant formulations. Here, we show evidence that a cocktail of vitamins A, C, and E along with Mg++ (ACEMg), previously shown to protect against noise-induced hearing loss, reverses auditory threshold shifts, promotes outer hair cell survival, and attenuates oxidative stress in the cochlea after cisplatin treatment, thus protecting against extreme cisplatin ototoxicity in rats. The addition of 500 mg N-acetylcysteine (NAC), which, administered individually, also shows significant attenuation of cisplatin ototoxicity, to the ACEMg formulation results in functional degradation of ACEMg otoprotection. Mg++ administered alone, as MgSO4, also prevents cisplatin ototoxicity, but in combination with 500 mg NAC, otoprotection is also greatly degraded. Increasing the dose of NAC to 1000 mg also results in dramatic loss of otoprotection activity compared with 500 mg NAC. These findings support that single antioxidants or antioxidant combinations, particularly ACEMg in this experimental series, have significant otoprotection efficacy against cisplatin ototoxicity. However, an excess of combined antioxidants and/or elevated doses, above a yet-to-be-defined "antioxidation threshold", results in unrecoverable redox imbalance with loss of otoprotectant activity.

Redox-Active Compounds in the Therapy of Drug-Resistant Murine Leukemia P388 Strains

The efficiency of combinations of cytostatics cisplatin and adriamycin with antioxidant sodium 3-(3'-tert-butyl-4-hydroxyphenyl)propyl thiosulfate (TS-13), and nitric oxide (NO) donor NaNO2 was evaluated on two drug-resistant strains of leukemia P388 with changed redox-status of cells. Simultaneous use of both NO donor and TS-13 in combinations with the cytostatics did not increase the efficiency of therapy. In addition, antioxidant activity of TS-13, NaNO2, and their combinations was studied by the method of luminol-dependent chemiluminescence on the model systems with the use of the homogenized cells of sensitive strain and two drug-resistant strains of leukemia P388. It was shown that TS-13 and NO donor produced opposite effects: TS-13 decreased, while NO donor increased the content of free radicals in the model system. Combinations of antioxidant TS-13 and NO donor should be used with consideration for the redox-status of tumor treated.

Cisplatin in the era of PARP inhibitors and immunotherapy

Platinum compounds such as cisplatin, carboplatin and oxaliplatin are widely used in chemotherapy. Cisplatin induces cytotoxic DNA damage that blocks DNA replication and gene transcription, leading to arrest of cell proliferation. Although platinum therapy alone is effective against many tumors, cancer cells can adapt to the treatment and gain resistance. The mechanisms for cisplatin resistance are complex, including low DNA damage formation, high DNA repair capacity, changes in apoptosis signaling pathways, rewired cell metabolisms, and others. Drug resistance compromises the clinical efficacy and calls for new strategies by combining cisplatin with other therapies. Exciting progress in cancer treatment, particularly development of poly (ADP-ribose) polymerase (PARP) inhibitors and immune checkpoint inhibitors, opened a new chapter to combine cisplatin with these new cancer therapies. In this Review, we discuss how platinum synergizes with PARP inhibitors and immunotherapy to bring new hope to cancer patients.

Chlorogenic acid co-administration alleviates cisplatin-induced peripheral neuropathy in rats

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is still an unresolved problem in cisplatin (CIS) use.

OBJECTIVES

This study investigates possible anti-neuropathic effect of chlorogenic acid (CGA) against CIS-induced CIPN in rats while also investigating the contribution of nitric oxide (NO) to this phenomenon.

METHODS

Initially, CGA (250-1000 μM) was tested by MTT assay on primary DRG neurons. Subsequently, CIPN was induced in Sprague-Dawley rats by 3 mg/kg intraperitoneal injections of CIS once/week for 5 weeks. CGA (100 mg/kg) was co-administered with CIS, both alone and in combination with l-arginine (LARG) or l-nitro-arginine-methyl-ester (LNAME), to elucidate the contribution of nitrergic system to anti-neuropathic effects. Mechanical allodynia, thermal hyperalgesia, and cold plate tests were performed to test CIPN. Rotarod, footprint analysis, and activitymeter were used to evaluate motor coordination and performance. Tumor necrosis factor alpha (TNF-α) was measured as a marker of inflammation. Histological evaluations of DRG and sciatic nerves (SNs) were performed utilizing toluidine blue staining. Two-way analysis of variance and Kruskal-Wallis following Tukey's test were used as statistical analysis.

RESULTS

Higher concentration of CGA (1000 μM) exhibited protective effect against in vitro neurotoxicity. Neither LARG nor LNAME exerted significant change in this effect. Co-administration of CGA alleviated histological abnormalities and neuropathic effects induced by CIS. Ameliorative effect of CGA was not changed in mechanical allodynia but attenuated in cold allodynia, and motor activity/coordination tests by LARG and LNAME. Neuropathic effects of CIS remained unchanged with LARG and LNAME in behavioral experiments.

CONCLUSION

The study identified CGA as candidate agent in mitigating CIPN. NO seems to play a modulatory role in this effect.

A G-quadruplex-binding platinum complex induces cancer mitochondrial dysfunction through dual-targeting mitochondrial and nuclear G4 enriched genome

BACKGROUND

G-quadruplex DNA (G4) is a non-canonical structure forming in guanine-rich regions, which play a vital role in cancer biology and are now being acknowledged in both nuclear and mitochondrial (mt) genome. However, the impact of G4-based targeted therapy on both nuclear and mt genome, affecting mt function and its underlying mechanisms remain largely unexplored.

METHODS

The mechanisms of action and therapeutic effects of a G4-binding platinum(II) complex, Pt-ttpy, on mitochondria were conducted through a comprehensive approaches with in vitro and in vivo models, including ICP-MS for platinum measurement, PCR-based genetic analysis, western blotting (WB), confocal microscope for mt morphology study, extracellular flux analyzer, JC1 and Annexin V apoptosis assay, flow cytometry and high content microscope screening with single-cell quantification of both ROS and mt specific ROS, as well as click-chemistry for IF study of mt translation. Decipher Pt-ttpy effects on nuclear-encoded mt related genes expression were undertaken via RNA-seq, Chip-seq and CUT-RUN assays.

RESULTS

Pt-ttpy, shows a highest accumulation in the mitochondria of A2780 cancer cells as compared with two other platinum(II) complexes with no/weak G4-binding properties, Pt-tpy and cisplatin. Pt-ttpy induces mtDNA deletion, copy reduction and transcription inhibition, hindering mt protein translation. Functional analysis reveals potent mt dysfunction without reactive oxygen species (ROS) induction. Mechanistic study provided first evidence that most of mt ribosome genes are highly enriched in G4 structures in their promoter regions, notably, Pt-ttpy impairs most nuclear-encoded mt ribosome genes' transcription through dampening the recruiting of transcription initiation and elongation factors of NELFB and TAF1 to their promoter with G4-enriched sequences. In vivo studies show Pt-ttpy's efficient anti-tumor effects, disrupting mt genome function with fewer side effects than cisplatin.

CONCLUSION

This study underscores Pt-ttpy as a G4-binding platinum(II) complex, effectively targeting cancer mitochondria through dual action on mt and nuclear G4-enriched genomes without inducing ROS, offering promise for safer and effective platinum-based G4-targeted cancer therapy.

Pharmacogenomic analysis in adrenocortical carcinoma reveals genetic features associated with mitotane sensitivity and potential therapeutics

Background

Adrenocortical carcinoma (ACC) is an aggressive endocrine malignancy with limited therapeutic options. Treating advanced ACC with mitotane, the cornerstone therapy, remains challenging, thus underscoring the significance to predict mitotane response prior to treatment and seek other effective therapeutic strategies.

Objective

We aimed to determine the efficacy of mitotane via an in vitro assay using patient-derived ACC cells (PDCs), identify molecular biomarkers associated with mitotane response and preliminarily explore potential agents for ACC.

Methods

In vitro mitotane sensitivity testing was performed in 17 PDCs and high-throughput screening against 40 compounds was conducted in 8 PDCs. Genetic features were evaluated in 9 samples using exomic and transcriptomic sequencing.

Results

PDCs exhibited variable sensitivity to mitotane treatment. The median cell viability inhibition rate was 48.4% (IQR: 39.3-59.3%) and -1.2% (IQR: -26.4-22.1%) in responders (n=8) and non-responders (n=9), respectively. Median IC50 and AUC were remarkably lower in responders (IC50: 53.4 µM vs 74.7 µM, P<0.0001; AUC: 158.0 vs 213.5, P<0.0001). Genomic analysis revealed CTNNB1 somatic alterations were only found in responders (3/5) while ZNRF3 alterations only in non-responders (3/4). Transcriptomic profiling found pathways associated with lipid metabolism were upregulated in responder tumors whilst CYP27A1 and ABCA1 expression were positively correlated to in vitro mitotane sensitivity. Furthermore, pharmacologic analysis identified that compounds including disulfiram, niclosamide and bortezomib exhibited efficacy against PDCs.

Conclusion

ACC PDCs could be useful for testing drug response, drug repurposing and guiding personalized therapies. Our results suggested response to mitotane might be associated with the dependency on lipid metabolism. CYP27A1 and ABCA1 expression could be predictive markers for mitotane response, and disulfiram, niclosamide and bortezomib could be potential therapeutics, both warranting further investigation.

Effects of pyrrolopyrimidine derivatives on cancer cells cultured in vitro and potential mechanism

In this study, the anticancer activities of some pyrrolopyrimidine derivatives were evaluated. Compound 3 is the most cytotoxic compound on MCF-7 cancer cells with an IC50 value of 23.42 µM. Also, compound 3 induced apoptosis and the ROS(+) cell population in MCF-7 cells. Moreover, it significantly reduced MMP-9 activity, having 42.16 ± 5.10% and 58.28 ± 1.96% inhibitory activities at 10 µM and 50 µM concentrations, respectively. Molecular docking results supported the activity, showing key hydrogen bonds with the binding site of MMP-9. Therefore, compound 3 might be a lead compound for the development of potent MMP-9 inhibitors.