[50th anniversary of cisplatin]

Management of Cisplatin-Induced Encephalopathy: A Case Report and Literature Review

Cisplatin is a cancer therapy drug commonly used. It is well-known for its antineoplastic properties, as well as for its numerous adverse effects, particularly its neurotoxicity. Symptoms associated with a central nervous system injury are unusual but can present a diagnostic challenge. Here, we report a case of a 62-year-old patient who was diagnosed with undifferentiated nasopharyngeal carcinoma. Cisplatin-based chemotherapy was administrated. Five days following the second cycle of treatment, the patient presented neurological disorders. A full biological workup and brain imaging were requested and revealed no abnormalities. The diagnosis of cisplatin encephalopathy was then suspected. Twenty days after cessation of cisplatin therapy, the neurological symptoms began to improve. Based on our case and a review of the literature, cisplatin-induced encephalopathy remains unusual. Its diagnosis is based on a combination of clinical, biological, and radiological criteria and requires the exclusion of other etiologies for neurological disorders in a patient being treated for cancer. Treatment is symptomatic and depends on stopping cisplatin therapy. These neurological adverse effects are often transitory and disappear without major repercussions.

Nicorandil attenuates cisplatin-induced acute kidney injury in rats via activation of PI3K/AKT/mTOR signaling cascade and inhibition of autophagy

Cisplatin is a highly effective antitumor agent, but its clinical use is limited due to critical adverse reactions including acute kidney injury (AKI). Nicorandil is an approved antianginal agent decreasing ischemia by potassium channel opening. The aim of this study was to investigate the nephroprotective effects of nicorandil and the possible role of activating PI3K/AKT/mTOR pathway in ameliorating cisplatin-induced AKI. Forty male Wistar rats were randomly allocated in 4 groups (n = 10). Group I: rats received the vehicle and served as control. Group II: rats received a single dose of cisplatin (7 mg/kg, i.p) on the 10th day of the experiment and served as AKI group. Group III: rats received cisplatin as in group II and nicorandil (3 mg/kg/day, p.o) for 14 days. Group IV: rats received cisplatin and nicorandil as in group III as well as wortmannin (15 μg/kg, i.v) for 14 days. Nicorandil exhibited obvious nephroprotective effects via the activation of PI3K/AKT/mTOR pathway. Moreover, nicorandil succeed to reduce the expression of the autophagy markers beclin-1 and LC-3II/I. In parallel, nicorandil showed anti-inflammatory and antiapoptotic effects via inhibition of NF-κB inflammatory pathway and depression of Bax/Bcl-2 ratio. Wortmannin, the PI3K inhibitor, was used to demonstrate the proposed pathway. Our study showed the nephroprotective effects of nicorandil in cisplatin-induced AKI in rats via activation of PI3K/AKT/mTOR signaling cascade, inhibition of autophagy, anti-inflammatory, anti-apoptotic, anti-oxidant activities. Thus, nicorandil could represent a promising renoprotective agent in cancer patients treated with cisplatin.

Lysine demethylase 5B (KDM5B): A key regulator of cancer drug resistance

Chemoresistance, a roadblock in the chemotherapy process, has been impeding its effective treatment. KDM5B, a member of the histone demethylase family, has been crucial in the emergence and growth of malignancies. More significantly, KDM5B has recently been linked closely to cancer's resistance to chemotherapy. In this review, we explain the biological properties of KDM5B, its function in the emergence and evolution of cancer treatment resistance, and our hopes for future drug resistance-busting combinations involving KDM5B and related targets or medications.

Advance in integrating platinum-based chemotherapy with radiotherapy for locally advanced nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant tumor characterized by the malignant transformation of nasopharyngeal epithelial cells. It is highly sensitive to radiation therapy, making radiotherapy the primary treatment modality. However, 60-80% of patients are initially diagnosed with locally advanced NPC (LA-NPC), where radiotherapy alone often fails to achieve desirable outcomes. Therefore, combining radiotherapy with chemotherapy has emerged as an effective strategy to optimize treatment for LA-NPC patients. Among the various chemotherapy regimens, concurrent chemoradiotherapy (CCRT) using platinum-based drugs has been established as the most commonly utilized approach for LA-NPC patients. The extensive utilization of platinum drugs in clinical settings underscores their therapeutic potential and emphasizes ongoing efforts in the development of novel platinum-based complexes for anticancer therapy. The aim of this review is to elucidate the remarkable advances made in the field of platinum-based therapies for nasopharyngeal carcinoma, emphasizing their transformative impact on patient prognosis.

Triphenylphosphonium-functionalized N-heterocyclic carbene platinum complexes [(NHC-TPP+)Pt] induce cell death of human glioblastoma cancer stem cells

A growing body of experimental and clinical evidence suggests that rare cell populations, known as cancer stem cells (CSCs), play an important role in the development and therapeutic resistance of several cancers, including glioblastoma. Elimination of these cells is therefore of paramount importance. Interestingly, recent results have shown that the use of drugs that specifically disrupt mitochondria or induce mitochondria-dependent apoptosis can efficiently kill cancer stem cells. In this context, a novel series of platinum(II) complexes bearing N-heterocyclic carbene (NHC) of the type [(NHC)PtI2(L)] modified with the mitochondria targeting group triphenylphosphonium were synthesized. After a complete characterization of the platinum complexes, the cytotoxicity against two different cancer cell lines, including a cancer stem cell line, was investigated. The best compound reduced the cell viability of both cell lines by 50% in the mM range, with an approximately 300-fold higher anticancer activity on the CSC line compared to oxaliplatin. Finally, mechanistic studies showed that the triphenylphosphonium functionalized platinum complexes significantly altered mitochondrial function and also induced atypical cell death.

Methylene Blue Induces Antioxidant Defense and Reparation of Mitochondrial DNA in a Nrf2-Dependent Manner during Cisplatin-Induced Renal Toxicity

Cisplatin is a platinum-based cytostatic drug that is widely used for cancer treatment. Mitochondria and mtDNA are important targets for platinum-based cytostatics, which mediates its nephrotoxicity. It is important to develop therapeutic approaches to protect the kidneys from cisplatin during chemotherapy. We showed that the exposure of mitochondria to cisplatin increased the level of lipid peroxidation products in the in vitro experiment. Cisplatin caused strong damage to renal mtDNA, both in the in vivo and in vitro experiments. Cisplatin injections induced oxidative stress by depleting renal antioxidants at the transcriptome level but did not increase the rate of H₂O₂ production in isolated mitochondria. Methylene blue, on the contrary, induced mitochondrial H₂O₂ production. We supposed that methylene blue-induced H₂O₂ production led to activation of the Nrf2/ARE signaling pathway. The consequences of activation of this signaling pathway were manifested in an increase in the expression of some antioxidant genes, which likely caused a decrease in the amount of mtDNA damage. Methylene blue treatment induced an increase in the expression of genes that were involved in the base excision repair (BER) pathway: the main pathway for mtDNA reparation. It is known that the expression of these genes can also be regulated by the Nrf2/ARE signaling pathway. We can assume that the protective effect of methylene blue is related to the activation of Nrf2/ARE signaling pathways, which can activate the expression of genes related to antioxidant defense and mtDNA reparation. Thus, the protection of kidney mitochondria from cisplatin-induced damage using methylene blue can significantly expand its application in medicine.

A significantly non-toxic novel Cobalt(III) Schiff base complex induces apoptosis via G2-M cell cycle arrest in human breast cancer cell line MCF-7

AIMS

Metal complexes have ignited considerable interest in the field of chemotherapy after the serendipitous discovery of cisplatin but the severe toxicity of these platinum-based drugs compelled researchers to search for newer, more effective lesser toxic anticancer drugs.

MATERIALS AND METHODS

Structural analysis is done by different physicochemical techniques including X-ray single crystallography. Toxicity study has been done in normal Swiss albino mice. MTT assay assessed cell viability. Apoptosis, cell cycle arrest, and cell proliferation were assessed by FACS using Annexin V-PI, PI, and CFSE staining respectively. Western blot quantifies protein expression. While cell migration was studied by wound healing assay.

KEY FINDINGS

One-pot synthesis of a novel mononuclear cobalt(III)-Schiff base complex (1) (>99 % purity) and its complete characterization have been done. Cell viability assay showed that 1 (IC₅₀ = 16.81 ± 1.33 μM) exhibits cytotoxicity at much lower concentration in comparison to oxaliplatin (IC₅₀ = 31.4 ± 0.69 μM) against MCF-7 cells for 24 h of therapy without being overly toxic to human PBMCs (IC₅₀ ≥ 60 μM). Additional in vitro studies demonstrated that 1 induces apoptosis via G2-M cell cycle arrest and reduces cell proliferation as well as cell migration in MCF-7 cells. In vivo subacute toxicity (28 days) and systemic chronic toxicity (40 days) studies were carried out in normal Swiss albino mice showed 1 is significantly nontoxic to the host.

SIGNIFICANCE

The readily synthesizable, significantly nontoxic cobalt complex with appreciable anticancer activity implies that it might be an effective chemotherapeutic agent for new-age anti-tumor medication.

Cisplatin Chemotherapy and Cochlear Damage: Otoprotective and Chemosensitization Properties of Polyphenols

Significance: Cisplatin is an important component of treatment regimens for different cancers. Notwithstanding that therapeutic success often results from partial efficacy or stabilizing the disease, chemotherapy failure is driven by resistance to drug treatment and occurrence of side effects, such as progressive irreversible ototoxicity. Cisplatin's side effects, including ototoxicity, are often dose limiting. Recent Advances: Cisplatin ototoxicity results from several mechanisms, including redox imbalance caused by reactive oxygen species production and lipid peroxidation, activation of inflammation, and p53 and its downstream pathways that culminate in apoptosis. Considerable efforts in research have targeted development of molecular interventions that can be concurrently administered with cisplatin or other chemotherapies to reduce side effect toxicities while preserving or enhancing the antineoplastic effects. Evidence from studies has indicated some polyphenols, such as curcumin, can help to regulate redox signaling and inflammatory effects. Furthermore, polyphenols can exert opposing effects in different types of tissues, that is, normal cells undergoing stressful conditions versus cancer cells. Critical Issues: This review article summarizes evidence of curcumin antioxidant effect against cisplatin-induced ototoxicity that is converted to a pro-oxidant activity in cisplatin-treated cancer cells, thus providing an ideal chemosensitivity combined with otoprotection. Polyphenols can modulate the adaptive responses to stress in the cisplatin-exposed cochlea. These adaptive effects can result from the interaction/cross talk between the cell's defenses, inflammatory molecules, and the key signaling molecules of signal transducers and activators of transcription 3 (STAT-3), nuclear factor κ-B (NF-κB), p53, and nuclear factor erythroid 2-related factor 2 (Nrf-2). Future Directions: We provide molecular evidence for alternative strategies for chemotherapy with cisplatin addressing the otoprotection and chemosensitization properties of polyphenols. Antioxid. Redox Signal. 36, 1229-1245.

The Rationale for "Laser-Induced Thermal Therapy (LITT) and Intratumoral Cisplatin" Approach for Cancer Treatment

Cisplatin is one of the most widely used anticancer drugs in the treatment of various types of solid human cancers, as well as germ cell tumors, sarcomas, and lymphomas. Strong evidence from research has demonstrated higher efficacy of a combination of cisplatin and derivatives, together with hyperthermia and light, in overcoming drug resistance and improving tumoricidal efficacy. It is well known that the antioncogenic potential of CDDP is markedly enhanced by hyperthermia compared to drug treatment alone. However, more recently, accelerators of high energy particles, such as synchrotrons, have been used to produce powerful and monochromatizable radiation to induce an Auger electron cascade in cis-platinum molecules. This is the concept that makes photoactivation of cis-platinum theoretically possible. Both heat and light increase cisplatin anticancer activity via multiple mechanisms, generating DNA lesions by interacting with purine bases in DNA followed by activation of several signal transduction pathways which finally lead to apoptosis. For the past twenty-seven years, our group has developed infrared photo-thermal activation of cisplatin for cancer treatment from bench to bedside. The future development of photoactivatable prodrugs of platinum-based agents injected intratumorally will increase selectivity, lower toxicity and increase efficacy of this important class of antitumor drugs, particularly when treating tumors accessible to laser-based fiber-optic devices, as in head and neck cancer. In this article, the mechanistic rationale of combined intratumor injections of cisplatin and laser-induced thermal therapy (CDDP-LITT) and the clinical application of such minimally invasive treatment for cancer are reviewed.

Solasonine induces apoptosis of the SGC-7901 human gastric cancer cell line in vitro via the mitochondria-mediated pathway

Solasonine, a steroidal glycoalkaloid isolated from the herbal plant Solanum nigrum Linn., has shown active against multiple human cancers; however, there is little knowledge on the activity of solasonine against gastric cancer until now. This study aimed to examine the effect of solasonine on the biological behaviours of human gastric cancer SGC‐7901 cells. The results showed that solasonine suppressed SGC‐7901 cell proliferation in a dose‐dependent manner. Solasonine treatment mainly induced the cell cycle arrest at G2 phase in SGC‐7901 cells. Treatment with solasonine resulted in significant down‐regulation of Bcl‐2 and Caspase‐3 protein expression and reduced Bax and Bcl‐xL protein expression in SGC‐7901 cells. Solasonine shows a comparable inhibitory effect on the proliferation of human gastric cancer SGC‐7901 cells with cisplatin, and solasonine induces of SGC‐7901 cell apoptosis through triggering the endoplasmic reticulum stress pathway and the mitochondrial pathway. Our data indicate that solasonine may be a promising agent for the treatment of gastric cancer.

Bioactivity and Development of Small Non-Platinum Metal-Based Chemotherapeutics

Countless expectations converge in the multidisciplinary endeavour for the search and development of effective and safe drugs in fighting cancer. Although they still embody a minority of the pharmacological agents currently in clinical use, metal-based complexes have great yet unexplored potential, which probably hides forthcoming anticancer drugs. Following the historical success of cisplatin and congeners, but also taking advantage of conventional chemotherapy limitations that emerged with applications in the clinic, the design and development of non-platinum metal-based chemotherapeutics, either as drugs or prodrugs, represents a rapidly evolving field wherein candidate compounds can be fine-tuned to access interactions with druggable biological targets. Moving in this direction, over the last few decades platinum family metals, e.g., ruthenium and palladium, have been largely proposed. Indeed, transition metals and molecular platforms where they originate are endowed with unique chemical and biological features based on, but not limited to, redox activity and coordination geometries, as well as ligand selection (including their inherent reactivity and bioactivity). Herein, current applications and progress in metal-based chemoth are reviewed. Converging on the recent literature, new attractive chemotherapeutics based on transition metals other than platinum—and their bioactivity and mechanisms of action—are examined and discussed. A special focus is committed to anticancer agents based on ruthenium, palladium, rhodium, and iridium, but also to gold derivatives, for which more experimental data are nowadays available. Next to platinum-based agents, ruthenium-based candidate drugs were the first to reach the stage of clinical evaluation in humans, opening new scenarios for the development of alternative chemotherapeutic options to treat cancer.

The Employment of Genera Vaccinium, Citrus, Olea, and Cynara Polyphenols for the Reduction of Selected Anti-Cancer Drug Side Effects

Cancer is one of the most widespread diseases globally and one of the leading causes of death. Known cancer treatments are chemotherapy, surgery, radiation therapy, targeted hormonal therapy, or a combination of these methods. Antitumor drugs, with different mechanisms, interfere with cancer growth by destroying cancer cells. However, anticancer drugs are dangerous, as they significantly affect both cancer cells and healthy cells. In addition, there may be the onset of systemic side effects perceived and mutagenicity, teratogenicity, and further carcinogenicity. Many polyphenolic extracts, taken on top of common anti-tumor drugs, can participate in the anti-proliferative effect of drugs and significantly reduce the side effects developed. This review aims to discuss the current scientific knowledge of the protective effects of polyphenols of the genera Vaccinium, Citrus, Olea, and Cynara on the side effects induced by four known chemotherapy, Cisplatin, Doxorubicin, Tamoxifen, and Paclitaxel. In particular, the summarized data will help to understand whether polyphenols can be used as adjuvants in cancer therapy, although further clinical trials will provide crucial information.

Fish Collagen Peptides Protect against Cisplatin-Induced Cytotoxicity and Oxidative Injury by Inhibiting MAPK Signaling Pathways in Mouse Thymic Epithelial Cells

Thymic epithelial cells (TECs) account for the most abundant and dominant stromal component of the thymus, where T cells mature. Oxidative- or cytotoxic-stress associated injury in TECs, a significant and common problem in many clinical settings, may cause a compromised thymopoietic capacity of TECs, resulting in clinically significant immune deficiency disorders or impairment in the adaptive immune response in the body. The present study demonstrated that fish collagen peptides (FCP) increase cell viability, reduce intracellular levels of reactive oxygen species (ROS), and impede apoptosis by repressing the expression of Bax and Bad and the release of cytochrome c, and by upregulating the expression of Bcl-2 and Bcl-xL in cisplatin-treated TECs. These inhibitory effects of FCP on TEC damage occur via the suppression of ROS generation and MAPK (p38 MAPK, JNK, and ERK) activity. Taken together, our data suggest that FCP can be used as a promising protective agent against cytotoxic insults- or ROS-mediated TEC injury. Furthermore, our findings provide new insights into a therapeutic approach for the future application of FCP in the prevention and treatment of various types of oxidative- or cytotoxic stress-related cell injury in TECs as well as age-related or acute thymus involution.

Molecular mechanisms associated with chemoresistance in esophageal cancer

Esophageal cancer (EC) is one of the most incident and lethal tumors worldwide. Although surgical resection is an important approach in EC treatment, late diagnosis, metastasis and recurrence after surgery have led to the management of adjuvant and neoadjuvant therapies over the past few decades. In this scenario, 5-fluorouracil (5-FU) and cisplatin (CISP), and more recently paclitaxel (PTX) and carboplatin (CBP), have been traditionally used in EC treatment. However, chemoresistance to these agents along EC therapeutic management represents the main obstacle to successfully treat this malignancy. In this sense, despite the fact that most of chemotherapy drugs were discovered several decades ago, in many cases, including EC, they still represent the most affordable and widely employed treatment approach for these tumors. Therefore, this review summarizes the main mechanisms through which the response to the most widely chemotherapeutic agents used in EC treatment is impaired, such as drug metabolism, apoptosis resistance, cancer stem cells (CSCs), cell cycle, autophagy, energetic metabolism deregulation, tumor microenvironment and epigenetic modifications.

The influence of acute kidney disease on the clinical outcomes of patients who received cisplatin, carboplatin, and oxaliplatin

Background and Aims

Cisplatin (CDDP) is used as the first line of treatment for some tumors, but its use may be restricted due to its nephrotoxicity. Carboplatin (CARBO) and oxaliplatin (OXA) are less nephrotoxic alternatives to CDDP. This study has the objective to determine the incidence of acute kidney disease after chemotherapy with CDDP, CARBO, or OXA.

Methods

A clinical study of a retrospective cohort of patients who underwent treatment with CDDP, CARBO, or OXA from January‐December 2016. Acute kidney Disease (AKD) was defined as elevated serum creatinine (sCR) levels before and up to 3 months after chemotherapy. Morbidities, type of tumor, and treatment data were recorded.

Results

A total of 212 patients aged 55.5 ± 14.0 years were evaluated. Among the comorbidities, 30% had arterial hypertension (AH) and 11% had diabetes, and 18% were treated with CDDP, 41% with CARBO, and 41% with OXA. There was no difference in sCR levels before and after chemotherapy regardless of the chemotherapy used. The prevalence of eGFRs <60 mL/min after chemotherapy was higher in patients with AH and cardiovascular disease (CVD). The incidence of post‐chemotherapy AKD was 7.0% (n = 13) and the mortality rate was 38.2%. Survival was lower in patients with AKD (P = .012).

Conclusions

There was a low incidence of AKD among the patients regardless of the chemotherapy used, but the patients with AKD had shorter survival. In addition, the reduction in eGFR after chemotherapy was greater in patients with AH and CVD.

Cisplatin combined with capecitabine-induced chemotherapy for local nasopharyngeal carcinoma can improve the quality of life and reduce toxic and side effects

Background

This study was designed to probe into the effect of cisplatin combined with capecitabine on nasopharyngeal carcinoma (NPC).

Methods

A total of 136 NPC patients treated for the first time in our hospital from January 2016 to March 2017 were collected and divided into two groups: A and B. Among them, 66 in group A were treated with cisplatin intravenous drip, while 70 in group B were treated with capecitabine on the basis of group A. The efficacy, toxic and side effects, and quality of life of the two groups were observed.

Results

The short-term efficacy of group B was better than that of group A (p<0.05). The toxic and side effects of group B were lower than that of group A (p<0.05). The quality of life in group B was higher than that in group A (p<0.05).

Conclusions

Cisplatin combined with capecitabine-induced chemotherapy for local NPC can improve the quality of life and reduce the toxic and side effects.

Investigation of differentially expressed gene profile for cisplatin-treated lung cancer patients

The purpose of the study was to establish a comprehensive differential gene profile for lung cancer patients treated with cisplatin compared with control patients without any chemotherapy drug treatment. The RNA sequencing data and miRNA sequencing data of 108 lung cancer patients treated with cisplatin only and 232 lung cancer patients treated without any chemotherapeutic drugs, were analyzed using differential expression, protein-protein interaction, and immune cell infiltration ratio analysis. Compared with control patients, the cisplatin-treated patients demonstrated 336 differentially expressed genes, which included 48 upregulated genes and 288 downregulated genes. Meanwhile, 12 differentially expressed miRNAs (DEMs), including 7 upregulated miRNAs and 5 downregulated miRNAs showed a differentially expressed pattern. With further instigation, five miRNAs (hsa-miR-548ah, hsa-miR-466, hsa-miR-552, hsa-miR-371a, and hsa-miR-4445) were suggested to be the key targets in the cisplatin-treated patients. At the same time, we also found a significant correlation between the cisplatin treatment and six immune checkpoints including programmed cell death ligand. This study helped us better understand the potential targets and underline molecular mechanisms for cisplatin treatment and provided references to eliminate existing side effects in the future.

Curcumin-cisplatin chemotherapy: A novel strategy in promoting chemotherapy efficacy and reducing side effects

The efficacy of chemotherapy in cancer therapy is limited due to resistance, treatment selectivity, and severe adverse effects. Immunotherapy, chemotherapy, targeted therapy, radiation, and surgery are the most common therapeutic strategies for treatment, with chemotherapy being the most successful. Nonetheless, these treatments exhibit poor effectiveness due to toxicity and resistance. Therefore, combination therapies of natural products may be used as an effective and novel strategy to overcome such barriers. Cisplatin is a platinum-based chemotherapy agent, and when administered alone, it can lead to severe adverse effects and resistance mechanism resulting in therapeutic failure. Curcumin is a polyphenolic compound extracted from turmeric (Curcuma longa) exhibiting anticancer potential with minimal adverse effects. The combination therapy of curcumin and cisplatin is a novel strategy to mitigate/attenuate cisplatin-related adverse effects and improve the barrier of resistance reducing unwanted effects. However, there are uncertainties on the efficacy of curcumin, and more in depth and high-quality studies are needed. This review aims to explain the adverse effects related to individual cisplatin delivery, the positive outcome of individual curcumin delivery, and the combination therapy of curcumin and cisplatin from nano platform as a novel strategy for cancer therapy.

Effects of Rapamycin Combined with Cisplatin on Tumor Necrosis Factor TNF-α in MG-63 Cells

Rapamycin (RAPA) and cisplatin (CDDP) are used as clinical drugs in the treatment of various tumors, but there are few studies on the combination of RAPA and CDDP. Tumor necrosis factor α (TNF-α) plays an important role in tumorigenesis and development. This study is to explore the effects of RAPA combined with CDDP on the expression of TNF-α in osteosarcoma MG-63 cells. MG-63 cells were routinely cultured and divided into a control group, a RAPA group (20 μM), a CDDP group (20 μM), and a RAPA + CDDP group (20 μM + 20 μM). The four groups were treated with drugs for 24 and 48 h, respectively. Real-time polymerase chain reaction (PCR), Western blot (WB), and immunocytochemistry (ICC) were adopted to detect the expression of TNF-α gene and protein. The results of PCR showed that both the separate drug use and drug combination could significantly lower the relative expression quantity of TNF-α gene (*P < 0.5), but the combination was more effective (*P < 0.5); the expression quantity of TNF-α gene in the RAPA + CDDP group at 48 h was much lower than that at 24 h (***P < 0.001). The results of WB showed that both the separate drug use and drug combination could significantly lower the relative expression quantity of TNF-α protein, and the combination was more effective than separate drug use (*P < 0.05) and more effective at 48 h (***P < 0.001); the expression quantity of TNF-α protein in the same group at 48 h was much lower than that at 24 h (*P < 0.05). The results of ICC showed that both the separate drug use and drug combination could significantly lower the relative expression quantity of TNF-α protein, and the combination was more effective than separate drug use (**P < 0.01) and more effective at 48 h (***P < 0.001); the expression quantity of TNF-α protein in the same group at 48 h was much lower than that at 24 h (**P < 0.01). RAPA combined with CDDP can significantly reduce the expression of TNF-α in MG-63 cells, which is time dependent.

The Role of Tumour Metabolism in Cisplatin Resistance

Cisplatin is a chemotherapy drug commonly used in cancer treatment. Tumour cells are more sensitive to cisplatin than normal cells. Cisplatin exerts an antitumour effect by interfering with DNA replication and transcription processes. However, the drug-resistance properties of tumour cells often cause loss of cisplatin efficacy and failure of chemotherapy, leading to tumour progression. Owing to the large amounts of energy and compounds required by tumour cells, metabolic reprogramming plays an important part in the occurrence and development of tumours. The interplay between DNA damage repair and metabolism also has an effect on cisplatin resistance; the molecular changes to glucose metabolism, amino acid metabolism, lipid metabolism, and other metabolic pathways affect the cisplatin resistance of tumour cells. Here, we review the mechanism of action of cisplatin, the mechanism of resistance to cisplatin, the role of metabolic remodelling in tumorigenesis and development, and the effects of common metabolic pathways on cisplatin resistance.

Retinal toxicities of systemic anticancer drugs

Newer anticancer drugs have revolutionized cancer treatment in the last decade, but conventional chemotherapy still occupies a central position in many cancers, with combination therapy and newer methods of delivery increasing their efficacy while minimizing toxicities. We discuss the retinal toxicities of anticancer drugs with an emphasis on the mechanism of toxicity. Uveitis is seen with the use of v-raf murine sarcoma viral oncogene homolog B editing anticancer inhibitors as well as immunotherapy. Most of the cases are mild with only anterior uveitis, but severe cases of posterior uveitis, panuveitis, and Vogt-Koyanagi-Harada-like disease may also occur. In the retina, a transient neurosensory detachment is observed in almost all patients on mitogen-activated protein kinase kinase (MEK) inhibitors. Microvasculopathy is often seen with interferon α, but vascular occlusion is a more serious toxicity caused by interferon α and MEK inhibitors. Crystalline retinopathy with or without macular edema may occur with tamoxifen; however, even asymptomatic patients may develop cavitatory spaces seen on optical coherence tomography. A unique macular edema with angiographic silence is characteristic of taxanes. Delayed dark adaptation has been observed with fenretinide. Interestingly, this drug is finding potential application in Stargardt disease and age-related macular degeneration.

Curcumin in Osteosarcoma Therapy: Combining With Immunotherapy, Chemotherapeutics, Bone Tissue Engineering Materials and Potential Synergism With Photodynamic Therapy

Osteosarcoma is a dominating malignant bone tumor with high mortality due to pulmonary metastases. Furthermore, because of the cancer cell erosion and surgery resection, osteosarcoma always causes bone defects, which means dysfunction and disfigurement are seldom inevitable. Although various advanced treatments (e.g. chemotherapy, immunotherapy, radiotherapy) are coming up, the 5-year survival rate for osteosarcoma with metastases is still dismal. In line with this, the more potent treatments for osteosarcoma are in high demand. Curcumin, a perennial herb, has been reportedly applied in the therapy of various types of tumors via different mechanisms. In vitro, it has also been reported that curcumin can inhibit the proliferation of osteosarcoma cell lines and can be used to repair bone defects. This seems curcumin is a promising candidate in osteosarcoma treatment. However, due to its congenital property like hydrophobicity, and low bioavailability, affecting its anticancer effect, clinical applications of curcumin are highly limited. To enhance its performance in cancer therapies, some synergist approaches with curcumin have emerged. The present review presents some prospective ones (i.e. combinations with immunotherapy, chemotherapeutics, bone tissue engineering, and biomaterials) applied in osteosarcoma treatment. Additionally, with the advancements of photodynamic therapy in cancer therapy, this review also prospects the combination of curcumin with photodynamic therapy in osteosarcoma treatment.

Arene Ruthenium(II) Complexes Bearing the κ-P or κ-P,κ-S Ph2P(CH2)3SPh Ligand

Neutral [Ru(η⁶-arene)Cl₂{Ph₂P(CH₂)₃SPh-κP}] (arene = benzene, indane, 1,2,3,4-tetrahydronaphthalene: 2a, 2c and 2d) and cationic [Ru(η⁶-arene)Cl(Ph₂P(CH₂)₃SPh-κP,κS)]X complexes (arene = mesitylene, 1,4-dihydronaphthalene; X = Cl: 3b, 3e; arene = benzene, mesitylene, indane, 1,2,3,4-tetrahydronaphthalene, and 1,4-dihydronaphthalene; X = PF₆: 4a-4e) complexes were prepared and characterized by elemental analysis, IR, ¹H, ¹³C and ³¹P NMR spectroscopy and also by single-crystal X-ray diffraction analyses. The stability of the complexes has been investigated in DMSO. Complexes have been assessed for their cytotoxic activity against 518A2, 8505C, A253, MCF-7 and SW480 cell lines. Generally, complexes exhibited activity in the lower micromolar range; moreover, they are found to be more active than cisplatin. For the most active ruthenium(II) complex, 4b, bearing mesitylene as ligand, the mechanism of action against 8505C cisplatin resistant cell line was determined. Complex 4b induced apoptosis accompanied by caspase activation.

Gigantol inhibits proliferation and enhances DDP-induced apoptosis in breast-cancer cells by downregulating the PI3K/Akt/mTOR signaling pathway

AIMS

Gigantol is a bibenzyl compound isolated from orchids of the genus Dendrobium. Gigantol has been demonstrated to possess various pharmacologic (including anticancer) effects. Cisplatin (DDP) has been used and studied as the first-line agent for breast cancer (BC) treatment. Often, its efficacy is jeopardized due to intolerance and organ toxicity. We investigated if gigantol could enhance the anticancer effects of DDP in BC cells and its underlying mechanism of action.

MAIN METHODS

The potential pathway of gigantol in BC cells was detected by network-pharmacology and molecular-docking studies. The proliferation and apoptosis of BC cell lines were measured by the MTT assay, colony formation, Hoechst-33342 staining, and flow cytometry. Protein expression was measured by western blotting.

KEY FINDINGS

Gigantol could inhibit proliferation of BC cells and enhance DDP-induced apoptosis. According to the results of western blotting, gigantol reinforced DDP-induced anticancer effects through downregulation of the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway in BC cells. The effects were consistent with those of the pathway inhibitor LY294002.

SIGNIFICANCE

Our data might provide new insights into the underlying antitumor effect of gigantol in BC cells. This enhancement effect in the combination of gigantol and DDP may provide many therapeutic benefits in clinical treatment regimens against BC.

Simultaneously target of normal and stem cells-like gastric cancer cells via cisplatin and anti-CD133 CAR-T combination therapy

CD133 + cancer stem cells mediate chemoresistance in multiple aggressive cancers, and anti-CD133 chimeric antigen receptor T (CAR-T) cells are designed to selectively target cisplatin-resistant gastric cancer stem cells in this investigation. The relative CD133 expression was detected in gastric cancer patients before and after cisplatin treatment. Anti-CD133 CAR-T cells were incubated with cisplatin-exposed CD133⁺ BGC-823 cells to evaluate the killing efficacy. At the same time, the canonical T cell activation markers were assayed by fluorescence-activated cell sorting, and the functional cytokine profile was detected with enzyme-linked immunosorbent assays. In addition to the percentage of CD133 positive stem cell-like cells, the volume and weight of subcutaneous tumors in BGC-823, KATO III and MKN-28 xenograft models were measured to evaluate the anti-tumor activity of cisplatin and anti-CD133 CAR-T combination strategy. After cisplatin treatment, both human samples and BGC-823 cells showed up-regulated CD133 expression. Anti-CD133 CAR-T cells exhibited pronounced killing efficiency against cisplatin-exposed CD133⁺ BGC-823 cells with up-regulated activation markers and cytotoxicity cytokine production. Moreover, cisplatin and anti-CD133 CAR-T combination treatment inhibited tumor progression in three different xenograft models with diminished CD133 positive stem cell-like cell infiltration. These results indicate that cisplatin and anti-CD133 CAR-T combination strategy can simultaneously target normal and stem cell-like gastric cancer cells to improve the treatment outcome.

Effects of different combined regimens of cisplatin, metformin, and quercetin on nasopharyngeal carcinoma cells and subcutaneous xenografts

Cisplatin, metformin, and quercetin are all reliable anticancer drugs. However, it is unclear how effective their different combination regimens are on the growth of nasopharyngeal carcinoma cell line Sune-1 and subcutaneous xenograft in nude mice. This study evaluated the effects of single-drug, two-drug, and three-drug simultaneous or sequential combined application of these drugs on the growth of Sune-1 cells and subcutaneous xenograft tumors in nude mice. The results showed that the different combination regimens of cisplatin, metformin and quercetin all had significant inhibitory effects on the proliferation of Sune-1 cells and the growth of subcutaneous xenografts in nude mice (P < 0.01), and the inhibition rate of the three drugs simultaneous combined application was significant Higher than the two-drug combination or single-drug application (P < 0.05), the contribution level of each drug in the three-drug combination application from high to low were cisplatin > metformin > quercetin. In summary, our results indicate that the simultaneous combination of cisplatin, metformin, and quercetin may synergistically inhibit the growth of Sune-1 cells and subcutaneous xenografts in nude mice through their different anticancer mechanisms, which may be clinically refractory and provide reference for chemotherapy of patients with recurrent nasopharyngeal carcinoma.

Small Molecule Regulators of Ferroptosis

Ferroptosis is a dedicated mode of cell death involving iron, reactive oxygen species and lipid peroxidation. Involved in processes such as glutathione metabolism, lysosomal iron retention or interference with lipid metabolism, leading either to activation or inhibition of ferroptosis. Given the implications of ferroptosis in diseases such as cancer, aging, Alzheimer and infectious diseases, new molecular mechanisms underlying ferroptosis and small molecules regulators that target those mechanisms have prompted a great deal of interest. Here, we discuss the current scenario of small molecules modulating ferroptosis and critically assess what is known about their mechanisms of action.

MicroRNA-31 weakens cisplatin resistance of medulloblastoma cells via NF-κB and PI3K/AKT pathways

BACKGROUND

Medulloblastoma (MB) is a malignant intracranial tumor. Cisplatin is a broad-spectrum antitumor drug. It is important to study the cisplatin resistance of MB cells for the treatment of MB. In this article, we preliminarily studied the cisplatin resistance of microRNA (miR)-31 and the possible mechanism in DAOY and UW228 cells, laying a theoretical foundation for clinical treatment of MB.

METHODS

Following anti-miR-31 and pre-miR-31 transfections, cell viability, BrdU, CyclinD1, and apoptosis levels of DAOY and UW228 cell were detected by CCK8, BrdU, and western blot. Meanwhile, migration, invasion, and western blot assay were respectively used to detect the functions of miR-31 migration and invasion. miR-31 levels were changed by cell transfection and detected by RT-qPCR. Furthermore, the related-proteins of pathways were also detected by western blot.

RESULTS

Anti-miR-31 increased DAOY and UW228 cells viability, BrdU⁺ numbers, and expression of CyclinD1. The migration/invasion rate and expression levels of MMP-9 and vimentin after anti-miR-31 transfection were increased. Furthermore, anti-miR-31 enhanced cells' cisplatin resistance and triggered PI3K/AKT and NF-κB pathways. Pre-miR-31 played opposite roles and promoted the apoptosis.

CONCLUSION

miR-31 regulated cell growth, migration, invasion and cisplatin resistance of MB cells via PI3K/AKT and NF-κB pathways.

Effects of GPR81 silencing combined with cisplatin stimulation on biological function in hypopharyngeal squamous cell carcinoma

Hypopharyngeal squamous cell carcinoma (HSCC) is a malignant tumor found in the head and neck region. Lactate receptor 1, also known as G protein‑coupled receptor81 (GPR81), has been reported to play a vital role in cancer growth and metabolism. However, the function of GPR81 in HSCC remains largely unknown. The present study investigated the effect of GPR81 on cell survival and GPR81‑mediated energy metabolism under cisplatin treatment in HSCC. GPR81 knockdown reduced the proliferation and invasion of the human HSCC cell line FaDu. Furthermore, GPR81 silencing combined with cisplatin treatment increased the expression of translocase of outer mitochondrial membrane 20 at the mRNA and protein levels (P<0.05). mRNA and protein expression of phosphofructokinase 1 in mRNA appeared to be downregulated in GPR81 knockdown FaDu cells treated with cisplatin, although this was not statistically significant. GPR81 silencing and cisplatin challenge showed no significant upregulation compared with the control, but significant downregulation in mRNA and protein levels compared with the shRNA‑scramble group. Apoptosis was measured by flow cytometry with annexin V and 7‑aminoactinomycin D. GPR81 silencing and cisplatin led to an increased apoptotic rate. Moreover, absence of GPR81 combined with cisplatin exposure increased caspase‑3 expression and decreased Bcl‑2 levels. The results of the present study suggested that GPR81 and cisplatin sensitivity played an important role in HSCC growth and metabolism.

Beta-Blockers and Cancer: Where Are We?

Cancer is one of the leading causes of death worldwide. After diagnosis, cancer treatment may involve radiotherapy, chemotherapy, and surgery. Several of the approaches used to treat cancer also attack normal cells and, thus, there is the need for more effective treatments that decrease the toxicity to normal cells and increase the success rates of treatment. The use of beta-blockers in cancer has been studied for their antagonist action on the adrenergic system through inhibition of beta-adrenergic receptors. Besides regulating processes such as blood pressure, heart rate, and airway strength or reactivity, beta-blockers block mechanisms that trigger tumorigenesis, angiogenesis, and tumor metastasis. This study presents a literature review of the available studies addressing cancer treatments and beta-blockers. Overall, data suggest that propranolol may be used as a complement for the treatment of several types of cancer due to its ability to improve cancer outcomes by decreasing cancer cell proliferation rates. Nonetheless, additional in vitro studies should be performed to fully understand the protective role of BBs in cancer patients.

Hesperetin reverses P‑glycoprotein‑mediated cisplatin resistance in DDP‑resistant human lung cancer cells via modulation of the nuclear factor‑κB signaling pathway

Lung cancer is the leading cause of cancer-associated mortality worldwide. Cisplatin (DDP) is a first-line chemotherapeutic drug for the treatment of lung cancer; however, the majority of patients develop resistance to DDP. P-glycoprotein (P-gp), also referred to as multidrug resistance (MDR) protein 1, is associated with an MDR phenotype, which results in failure of cancer chemotherapy; thus, identifying effective MDR pump inhibitors may improve the outcomes of patients who develop resistance to treatment. Hesperetin is a derivative of hesperidin, which is extracted from tangerine peel and exhibits multiple antitumor properties. In the present study, human lung adenocarcinoma A549 and A549/DDP cells were treated with different concentrations of hesperetin and DDP, respectively. Furthermore, rhodamine 123 efflux assays, Cell Counting Kit-8 assays, immunofluorescence, reverse transcription-quantitative PCR and western blot analysis were used to elucidate the mechanisms underlying the effects of hesperetin On A549/DDP cells. Additionally, a xenograft model of lung cancer in nude mice was established to explore the effects of hesperetin on A549/DDP cell growth in vivo. The results demonstrated that hesperetin sensitized A549/DDP cells to DDP. In vivo, hesperetin pretreatment significantly inhibited tumor growth. Mechanistically, hesperetin markedly decreased the expression of P-gp and increased the intracellular accumulation of the P-gp substrate, rhodamine 123, in A549/DDP cells. In addition, pretreatment of A549/DDP cells with hesperetin significantly inhibited nuclear factor (NF)-κB (p65) activity and its nuclear translocation. Taken together, the results of the present study suggest that hesperetin reversed P-gp-mediated MDR by decreasing P-gp expression in A549/DDP cells, which was associated with inhibition of the NF-κB signaling pathway. These findings may provide the basis for the use of hesperetin clinically to reverse MDR.

Platinum Derivatives Effects on Anticancer Immune Response

Along with surgery and radiotherapy, chemotherapeutic agents belong to the therapeutic arsenal in cancer treatment. In addition to their direct cytotoxic effects, these agents also impact the host immune system, which might enhance or counteract their antitumor activity. The platinum derivative compounds family, mainly composed of carboplatin, cisplatin and oxaliplatin, belongs to the chemotherapeutical arsenal used in numerous cancer types. Here, we will focus on the effects of these molecules on antitumor immune response. These compounds can induce or not immunogenic cell death (ICD), and some strategies have been found to induce or further enhance it. They also regulate immune cells' fate. Platinum derivatives can lead to their activation. Additionally, they can also dampen immune cells by selective killing or inhibiting their activity, particularly by modulating immune checkpoints' expression.

Knockdown of long non-coding RNA LINC00152 increases cisplatin sensitivity in ovarian cancer cells

Drug resistance severely limits the effectiveness of chemotherapeutic treatment in ovarian cancer. The present study aimed to investigate the role of long non-coding RNA LINC00152 (LINC00152) in the cisplatin resistance of ovarian cancer. The expression level of LINC00152 was significantly increased in the ovarian cancer CoC1 and CoC1/DDP cell lines compared with the normal ovarian IOSE-80 cell line. To further investigate the function of LINC00152, small interfering RNAs (siRNAs) targeting LINC00152 were transfected into COC1 and COC1/DDP cells, which were subsequently treated with varying concentrations of cisplatin. The results revealed that LINC00152 silencing increased the apoptotic rates and enhanced the chemosensitivity of CoC1 and CoC1/DDP cells to cisplatin. Furthermore, downregulation of LINC00152 significantly decreased Bcl-2, and increased Bax and cleaved caspase-3 expression levels. Additionally, LINC00152 silencing decreased the expression of multidrug resistance-associated gene 1 (MDR1), multidrug resistance-associated protein 1 (MRP1) and glutathione S-transferase π (GSTπ). Collectively, the data demonstrated that LINC00152 knockdown increased the chemosensitivity of epithelial ovarian cancer cells to cisplatin by increasing apoptosis and decreasing the expression levels of MDR1, MRP1 and GSTπ.

FOXO3a from the Nucleus to the Mitochondria: A Round Trip in Cellular Stress Response

Cellular stress response is a universal mechanism that ensures the survival or negative selection of cells in challenging conditions. The transcription factor Forkhead box protein O3 (FOXO3a) is a core regulator of cellular homeostasis, stress response, and longevity since it can modulate a variety of stress responses upon nutrient shortage, oxidative stress, hypoxia, heat shock, and DNA damage. FOXO3a activity is regulated by post-translational modifications that drive its shuttling between different cellular compartments, thereby determining its inactivation (cytoplasm) or activation (nucleus and mitochondria). Depending on the stress stimulus and subcellular context, activated FOXO3a can induce specific sets of nuclear genes, including cell cycle inhibitors, pro-apoptotic genes, reactive oxygen species (ROS) scavengers, autophagy effectors, gluconeogenic enzymes, and others. On the other hand, upon glucose restriction, 5′-AMP-activated protein kinase (AMPK) and mitogen activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) -dependent FOXO3a mitochondrial translocation allows the transcription of oxidative phosphorylation (OXPHOS) genes, restoring cellular ATP levels, while in cancer cells, mitochondrial FOXO3a mediates survival upon genotoxic stress induced by chemotherapy. Interestingly, these target genes and their related pathways are diverse and sometimes antagonistic, suggesting that FOXO3a is an adaptable player in the dynamic homeostasis of normal and stressed cells. In this review, we describe the multiple roles of FOXO3a in cellular stress response, with a focus on both its nuclear and mitochondrial functions.

Combinations of the antioxidants sulforaphane or curcumin and the conventional antineoplastics cisplatin or doxorubicin as prospects for anticancer chemotherapy

Drugs used in clinical oncology have narrow therapeutic indices with adverse toxicity often involving oxidative damage. Chemoresistance to these conventional antineoplastics is usually mediated by oxidative stress-upregulated pathways such as those of nuclear factor-kappa B (NF-κB) and hypoxia-inducible factor-1 alpha (HIF-1α). Accordingly, the use of antioxidants in combinational approaches has begun to be considered for fighting cancer because of both the protective role against adverse effects and the ability to sensitize chemoresistant cancer cells. Nuclear factor erythroid 2-related factor 2 (Nrf2) has been identified as a mediator of the cytoprotection but it is not regularly associated with tumor chemosensitization. However, some Nrf2 inducers could be exerting cytoprotective and chemosensitizing roles through a simple integrated mechanism in which the cellular level of reactive oxygen species is controlled, thus inhibiting the oxidative damage in non-target tissues and the tumor chemoresistance mediated by NF-κB or HIF-1α. As examples to show the general idea of this antioxidant combination chemotherapy, this review explores the preclinical information available for four combinations, each composed by a paradigmatic oncological drug (cisplatin or doxorubicin) and a recognized antioxidant (sulforaphane or curcumin). The issues for translating these outcomes to clinical trials are briefly discussed.

Outcome Definition Influences the Relationship Between Genetic Polymorphisms of ERCC1, ERCC2, SLC22A2 and Cisplatin Nephrotoxicity in Adult Testicular Cancer Patients

Although previous research identified candidate genetic polymorphisms associated with cisplatin nephrotoxicity, varying outcome definitions potentially contributed to the variability in the effect size and direction of this relationship. We selected genetic variants that have been significantly associated with cisplatin-induced nephrotoxicity in more than one published study (SLC22A2 rs316019; ERCC1 rs11615 and rs3212986; ERCC2 rs1799793 and rs13181) and performed a replication analysis to confirm associations between these genetic polymorphisms and cisplatin nephrotoxicity using various outcome definitions. We included 282 germ cell testicular cancer patients treated with cisplatin from 2009-2014, aged >17 years recruited by the Canadian Pharmacogenomics Network for Drug Safety. Nephrotoxicity was defined using four grading tools: (1) Common Terminology Criteria for Adverse Events (CTCAE) v4.03 for acute kidney injury (AKI) or CTCAE-AKI; (2) adjusted cisplatin-induced AKI; (3) elevation of serum creatinine; and (4) reduction in the estimated glomerular filtration rate (eGFR). Significant associations were only found when using the CTCAE v4.03 definition: genotype CA of the ERCC1 rs3212986 was associated with decreased risk of cisplatin nephrotoxicity (ORadj = 0.24; 95% CI:0.08-0.70; p= 0.009) compared to genotype CC. In contrast, addition of allele A at SLC22A2 rs316019 was associated with increased risk (ORadj = 4.41; 95% CI:1.96-9.88; p < 0.001) while genotype AC was associated with a higher risk of cisplatin nephrotoxicity (ORadj = 5.06; 95% CI:1.69-15.16; p= 0.004) compared to genotype CC. Our study showed that different case definitions led to variability in the genetic risk ascertainment of cisplatin nephrotoxicity. Therefore, consensus on a set of clinically relevant outcome definitions that all such studies should follow is needed.

PINK1/Parkin-mediated mitophagy is activated in cisplatin nephrotoxicity to protect against kidney injury

Cisplatin is a widely used chemotherapeutic drug with notorious toxicity in the kidneys, which involves mitochondrial dysfunction and damage in renal tubular cells. Mitophagy is a form of selective autophagy that removes damaged or dysfunctional mitochondria to maintain cellular homeostasis. In this study, we have used mouse and cell models to examine the role and regulation of mitophagy in cisplatin nephrotoxicity. Cisplatin treatment was associated with the activation of autophagy and mitophagy. Rapamycin, a pharmacological inhibitor of mTOR, stimulated autophagy and mitophagy, and alleviated the development of cisplatin nephrotoxicity. PINK1 and Parkin were increased in kidney tissues during cisplatin treatment of mice. In PINK1 or Parkin gene knockout mouse models, both basal and cisplatin-induced mitophagy in kidneys were defective. Compared with wild-type littermates, PINK1 and Parkin knockout mice showed more severe renal functional loss, tissue damage, and apoptosis during cisplatin treatment. The results suggest that PINK1/Parkin-mediated mitophagy is activated in cisplatin nephrotoxicity and has a protective role against kidney injury.

CIP2A Promotes Proliferation, Invasion and Chemoresistance to Cisplatin in Renal Cell Carcinoma

CIP2A is a well-known oncoprotein whose expression is elevated in multiple human solid tumor types. However, its role in renal cell carcinoma (RCC) development is poorly understood. Thus, in our present study, we used the renal cancer cell lines 786-O, A498 and CAKI-1 and the renal epithelial cell line HK-2 to clarify the function of CIP2A in RCC. We found that CIP2A expression is much higher in the RCC cells than in the normal renal epithelial cell. Lentivirus covered coding region CIP2A cDNA sequence and CIP2A siRNA were used to up and down regulate CIP2A expression in vitro. We found that overexpression of CIP2A promoted G1/S transition and cell proliferation. In addition, up-regulation of CIP2A significantly enhanced the invasion and migration capabilities of the cells. Furthermore, CIP2A promoted epithelial-mesenchymal transformation (EMT) and chemoresistance to cisplatin in RCC cells. Taken together, our findings demonstrate that CIP2A plays an important role in proliferation, invasion and chemoresistance to cisplatin in RCC cells. CIP2A may serve as an ideal molecular target for RCC therapeutics.

KDM5B demethylates H3K4 to recruit XRCC1 and promote chemoresistance

Chemotherapy is the main treatment for human cancers including gastric cancer. However, in response to chemotherapeutic drugs, tumor cells can develop drug resistance by reprogramming intracellular metabolic and epigenetic networks to maintain their intrinsic homeostasis. Previously, we have established cisplatin-resistant gastric cancer cells as a drug resistant model, and elucidated the XRCC1 as the core DNA repair mechanism of drug resistance. This study investigated the regulation of XRCC1 by lysine demethylase 5B (KDM5B) in drug resistance. We found that the methylation level of H3K4 decreased significantly in drug-resistant cells. The chemical inhibitor of H3K4 demethylases, JIB-04, restored the methylation of H3K4 and blocked the co-localization of XRCC1 and γH2AX, eventually improved drug sensitivity. We further found that the expression level of KDM5B increased significantly in drug-resistant cells. Knockdown of KDM5B increased the methylation level of H3K4 and blocked the localization of XRCC1 to the DNA damage site, leads to increased drug sensitivity. In the sensitive cells, overexpression of KDM5B suppressed H3K4 methylation levels, which resulted to resistance to cisplatin. Moreover, we found that the posttranslational modification of KDM5B is responsible for its high expression in drug-resistant cells. Through mass spectrometry screening and co-immunoprecipitation validation, we found that the molecular chaperone HSP90 forms a complex with KDM5B in drug resistance cells. Interestingly, HSP90 inhibitor 17-AAG induced KDM5B degradation in a time-and-dose-dependent manner, indicating that HSP90 protected KDM5B from protein degradation. Targeting inhibition of HSP90 and KDM5B reversed drug resistance both in vitro and in vivo. Taken together, molecular chaperon HSP90 interacted with KDM5B to protect it from ubiquitin-dependent proteasomal degradation. Increased KDM5B demethylated H3K4 and facilitated the recruitment of XRCC1 to repair damaged DNA. Therefore, inhibition of HSP90 or KDM5B represented a novel approach to reverse chemoresistance in human cancers.

TAK1 mediates excessive autophagy via p38 and ERK in cisplatin-induced acute kidney injury

The ability of cisplatin (cis‐diamminedichloroplatinum II) toxicity to induce acute kidney injury (AKI) has attracted people's attention and concern for a long time, but its molecular mechanisms are still widely unknown. We found that the expression of transforming growth factor‐β (TGF‐β)‐activated kinase 1 (TAK1) could be increased in kidneys of mice administrated with cisplatin. Autophagy is an evolutionarily conserved catabolic pathway and is involved in various acute and chronic injuries. Moreover, p38 MAPK (mitogen‐activated protein kinase) and ERK regulate autophagy in response to various stimuli. Therefore, our hypothesis is that cisplatin activates TAK1, which phosphorylates p38 and ERK, leading to excessive autophagy of tubular epithelial cells and thus exacerbating kidney damage. Here, BALB/c mice were intraperitoneally injected with a TAK1 inhibitor and were then administrated with sham or cisplatin at 20 mg/kg by intraperitoneal injection. Compared with mice in the vehicle cisplatin group, mice intraperitoneally injected with a TAK1 inhibitor were found to have lower serum creatinine and less tubular damage following cisplatin‐induced AKI. Furthermore, inhibition of TAK1 reduced p38 and Erk phosphorylation, decreased expression of LC3II and reversed the down‐regulation of P62 expression induced by cisplatin. The hypothesis was verified with tubular epithelial cells administrated with cisplatin in vitro. Finally, p38 inhibitor or ERK inhibitor abated autophagy activation and cell viability reduction in tubular epithelial cells treated with cisplatin plus TAK1 overexpression vector. Taken together, our results show that cisplatin activates TAK1, which phosphorylates p38 and ERK, leading to excessive autophagy of tubular epithelial cells that exacerbates kidney damage.