Cisplatin-induced Cell Apoptosis Research Articles

Fibroblasts in metastatic lymph nodes confer cisplatin resistance to ESCC tumor cells via PI16

AbstractAlthough many studies have compared tumor fibroblasts (T-Fbs) and nontumor fibroblasts (N-Fbs), less is understood about the stromal contribution of metastatic lymph node fibroblasts (LN-Fbs) to the evolving microenvironment. Here, we explored the characteristics of LN-Fbs in esophageal squamous cell carcinoma (ESCC) and the interactions between fibroblasts and ESCC tumor cells in metastatic lymph nodes. Fibroblasts were isolated from tumor, nontumor and metastatic lymph node tissues from different patients with ESCC. Transcriptome sequencing was performed on the fibroblasts. Tumor growth and drug-resistance assays were carried out, and characteristics of T-Fbs, N-Fbs and LN-Fbs were determined. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to assay the culture medium of fibroblasts. The results demonstrated that fibroblasts derived from different tissues had different characteristics. Coculture with LN-Fbs conditioned medium inhibited ESCC tumor cell growth and induced chemoresistance in ESCC cells. LN-Fbs induced chemoresistance to cisplatin in ESCC cells by secreting PI16. Coculture with LN-Fbs conditioned medium decreased cisplatin-induced apoptosis in ESCC cells by regulating the p38 and JNK cell signaling pathways. Survival analyses showed that patients with high PI16 expression in Fbs of lymph nodes exhibited worse overall survival. We also examined PI16 expression in interstitial tissues in ESCC tumor samples of patients receiving platinum-based therapy postsurgery and found that high PI16 expression in tumor interstitial tissues was an independent prognostic factor for ESCC patients. In addition, an in vivo assay demonstrated that PI16 knockdown increased the sensitivity of ESCC cells to cisplatin. Our results suggest that fibroblasts in metastatic lymph nodes decrease apoptosis of ESCC cells via PI16, thereby providing a cisplatin-resistance niche and supporting ESCC tumor cells to survive in metastatic lymph nodes. PI16 is also a potential target for effectively blocking the chemoresistance niche signaling circuit in response to cisplatin.

The role of Her-2 in penile squamous cell carcinoma progression and cisplatin chemoresistance and potential for antibody-drug conjugate-based therapy

BackgroundCisplatin-based chemotherapy has been the first choice for advanced penile squamous cell carcinoma (PSCC) in the last decade, but its utility is limited by the low response rate, systemic toxicity, and chemoresistance, which contribute to a poor prognosis. There is no standard second-line therapy for advanced PSCC. Human epidermal growth factor receptor 2 (Her-2)-targeted antibody-drug conjugates (ADCs) are novel low-toxicity agents which have greatly improved clinical outcomes for several advanced cancers. We aimed to explore the expression pattern, clinical significance, and oncogenic roles of Her-2 and the therapeutic potential of Her-2-targeted ADCs in PSCC. MethodsHer-2 immunohistochemistry was performed for the largest single-centre PSCC cohort to date (367 patients). PSCC cell lines, cisplatin-resistant cell lines, subcutaneous xenograft, and footpad metastatic models were used to investigate the biological roles of Her-2 in PSCC progression. Cytotoxicity, apoptosis assays, and western blotting investigated the mechanism of Her-2 induced cisplatin-chemoresistance. The efficacy of Disitamab Vedotin (RC48), a Her-2-targeted ADC, was evaluated in PSCC. ResultsHer-2 was identified as an adverse prognostic indicator associated with advanced Tumor-Node-Metastasis (TNM) stages and poor survival with an immunohistochemical expression rate of approximately 47.7% (1+, 23.2%; 2+, 18.0%; 3+, 6.5%) in PSCC. Her-2 promotes cell proliferation, migration, invasion, tumour progression, and cisplatin resistance in PSCC. Mechanistically, Her-2 inhibits cisplatin-induced cell apoptosis by the activation of Akt phosphorylation at Ser473 and disrupts the balance between proapoptotic and antiapoptotic proteins. Meanwhile, cisplatin-resistant PSCC cells present aggressive oncogenic abilities and Her-2 upregulation. More importantly, RC48 displayed remarkable antitumor activities in both Her2-positive and cisplatin-resistant PSCC tumours. ConclusionOur study suggests that Her-2 is an available therapeutic biomarker for PSCC. Her-2-targeted ADC might have the potential to improve clinical outcomes in high-risk Her-2-positive advanced PSCC patients and provide precious second-line clinical choice for appropriate cisplatin-based chemoresistance patients.

The preventative effect of Baihe Gujin Pill on cisplatin-induced acute kidney injury by activating the PI3K/AKT and suppressing the NF-κB/MAPK pathways

Ethnopharmacological relevanceBaihe Gujin Pill (BHGJP) is a traditional Chinese medicine (TCM) derived from the “Collection of Medical Formulas”. BHGJP is applied to treat lung and kidney deficiency by nourishing yin and clearing heat. However, the role and preventative mechanism of BHGJP in cisplatin induced acute kidney injury (CIAKI) are poorly understood. Aim of the studyThe preventative effect of BHGJP on CIAKI by the in vitro and in vivo experiments based on network pharmacology was investigated. MethodsNetwork pharmacology was used to predict the protective effect of BHGJP on CIAKI. The effect and mechanism of BHGJP against CIAKI were detected and verified by the in vitro kidney cells 293T and HK-2 as well as the in vivo mice model established by a single injection of cisplatin. ResultsNetwork pharmacology predicted that BHGJP prevented CIAKI by regulating PI3K/AKT and NF-κB/MAPK signaling pathways. BHGJP could reverse the reduced cell viability of HK-2 and 293T cells caused by cisplatin without decreasing its cytotoxic effects on H460, H1299, and A549 cells. Meanwhile, BHGJP effectively controlled kidney injury in the CIAKI model. Moreover, cisplatin induced cell apoptosis and accumulation of reactive oxygen species (ROS) were downregulated after treatment with BHGJP. The changes of oxidative stress indexes of GSH, MDA, and SOD as well as the inflammatory factors of TNF-α, IL-6, and IL-1β in the CIAKI model were recovered to normal state when BHGJP treatment. Furthermore, BHGJP activated PI3K/AKT pathway and suppressed the NF-κB/MAPK pathway in the CIAKI model. ConclusionThe study found that BHGJP prevented CIAKI by inhibiting apoptosis, oxidative stress, and inflammation via regulating PI3K/AKT and NF-κB/MAPK pathways, providing new efficacy and clinical applications for BHGJP.

Her-2 promoting tumor progression and cisplatin resistance as a novel therapeutic target in penile squamous cell carcinoma.

67 Background: Cisplatin-based chemotherapy has been the first choice for advanced penile squamous cell carcinoma (PSCC) in the last decade, but remains challenging owing the unsatisfied response rates, frustrating systemic toxicity and chemoresistance leading to poor prognosis. There is no standard second-line therapy for advanced PSCC. Antibody-drug conjugates (ADC) were novel targeted and low-toxicity agents, of which Her-2 targeted ADCs widely used and have greatly improved clinical outcomes in breast, gastric and bladder cancers. We aimed to explore the expression pattern, clinical significance, oncogenic roles of Her-2 and the therapeutic potentiality of Her-2 target ADCs in PSCC. Methods: The immunohistochemical expression of Her-2 was detected in the largest single center cohort of 367 PSCC patients up to date. PSCC cell lines, cisplatin-resistant cell lines and animal models were established to investigated the biological roles of Her-2 in PSCC progression and cisplatin chemoresistance. Disitamab vedotin (RC48), an Her-2 targeted ADC drug, was used to evaluate the efficiency in PSCC. Results: Her-2 was an unfavourable prognostic indicator with around 47.7% immunohistochemical expression rate (1+, 23.2%; 2+, 18.0%; 3+, 6.5%) in PSCC. Her-2 positive immunohistochemical expression (2+/3+) was associated with advanced pT, pN stages, metastasis and poor overall survival (positive vs. negative, HR (95%Cl): 3.133 (2.120-4.631), p=0.000). Cellular and animal experiments confirmed that Her-2 promoted tumor progression, inhibited cisplatin-induced cell apoptosis via Akt pathways and increased cisplatin resistance in PSCC. Meanwhile, cisplatin-resistant PSCC cells up-regulated Her-2 expression. More importantly, Her-2 targeted ADCs Disitamab Vedotin displayed remarkable anti-tumor activities both in Her2-positive and cisplatin-resistant PSCC tumors. Conclusions: Our study suggested that Her-2 was an available therapeutic biomarker in PSCC. Targeting Her-2 ADCs might be a prospective option to improve clinical outcomes in high-risk Her-2 positive advanced PSCC patients and provided precious opportunity for cisplatin-based chemoresistance patients.

Adrenomedullin induces cisplatin chemoresistance in ovarian cancer through reprogramming of glucose metabolism.

The metabolic network of cancer cells has been reprogrammed - relying more on aerobic glycolysis to gain energy, which is an important reason for drug resistance. Expression of adrenomedullin (ADM) in ovarian cancer tissues is related to resistance to platinum-based drugs. In view of this, we intended to investigate the correlation between ADM and glucose metabolism reprogramming of tumor cells to clarify the possible mechanism of ADM-induced ovarian cancer cisplatin resistance through glucose metabolism reprogramming. Epithelial ovarian cancer (EOC) cell viability and apoptosis were determined. Different gene expression and protein levels were detected by real-time revere transcription polymerase chain reaction and western blotting. Oxygen consumption rate (OCR) and extracellular acidification rates (ECARs) were measured. ADM expression was upregulated in cisplatin-resistant EOC cells. ADM attenuated cisplatin-inhibited cell survival and cisplatin-induced apoptosis in sensitive EOC cells; knockdown of ADM enhanced cisplatin chemosensitivity of cisplatin-resistant EOC cells. ADM enhanced glycolysis in cisplatin-sensitive EOC cells; knockdown of ADM significantly inhibited glycolysis in cisplatin-resistant EOC cells. ADM significantly upregulated pyruvate kinase isozyme type M2 (PKM2) protein level, the key enzyme during glycolysis; PKM2 inhibitor significantly abolished the ADM-improved cell survival and ADM-inhibited apoptosis. ADM promoted proliferation and inhibited apoptosis of ovarian cancer cells through reprogramming of glucose metabolism, so as to promote cisplatin resistance. The study is expected to identify multidrug resistance markers of ovarian cancer and provide a target for the prevention and treatment of ovarian cancer, which is important for clinical translational research.

Inhibition of TMEM16A improves cisplatin-induced acute kidney injury via preventing DRP1-mediated mitochondrial fission.

Acute kidney injury (AKI) is associated with high morbidity and mortality. Our previous study has demonstrated that TMEM16A, a Ca2+-activated chloride channel, contributes to renal fibrosis progression in chronic kidney disease. However, whether TMEM16A isinvolved in AKI is still unknown. In this study, we established cisplatin AKI mice model and found that TMEM16A expression was upregulated in the injured kidney. In vivo knockdown of TMEM16A effectively prevented cisplatin-induced tubular cell apoptosis, inflammation and kidney function loss. Western blot and transmission electron microscopy (TEM) revealed that TMEM16A knockdown inhibited Drp1 translocation from the cytoplasm to mitochondria and prevented mitochondrial fission in tubular cells. Consistently, in cultured HK2 cells, knockdown or inhibition of TMEM16A by shRNA or its specific inhibitor suppressed cisplatin-induced mitochondrial fission and its associated energy dysfunction, ROS accumulation, and cell apoptosis via inhibiting Drp1 activation. Further investigation showed that genetic knockdown or pharmacological inhibition of TMEM16A inhibited cisplatin-induced Drp1 Ser-616 site phosphorylation through ERK1/2 signaling pathway, whereas overexpression of TMEM16A promoted this effect. Treatment with Drp1 or ERK1/2 inhibitor could efficiently prevent cisplatin-induced mitochondrial fission. Collectively, our data suggest that TMEM16A inhibition alleviated cisplatin-induced AKI by preventing tubular cell mitochondrial fission through the ERK1/2 / Drp1 pathway. Inhibition of TMEM16A may be a novel therapeutic strategy for AKI.

Tim-3 protects against cisplatin nephrotoxicity by inhibiting NF-κB-mediated inflammation

The impact of Tim-3 (T cell immunoglobulin and mucin domain-containing protein 3) on cisplatin-induced acute kidney injury was investigated in this study. Cisplatin-induced Tim-3 expression in mice kidney tissues and proximal tubule-derived BUMPT cells in a time-dependent manner. Compared with wild-type mice, Tim-3 knockout mice have higher levels of serum creatinine and urea nitrogen, enhanced TUNEL staining signals, more severe 8-OHdG (8-hydroxy-2’ -deoxyguanosine) accumulation, and increased cleavage of caspase 3. The purified soluble Tim-3 (sTim-3) protein was used to intervene in cisplatin-stimulated BUMPT cells by competitively binding to the Tim-3 ligand. sTim-3 obviously increased the cisplatin-induced cell apoptosis. Under cisplatin treatment conditions, Tim-3 knockout or sTim-3 promoted the expression of TNF-α (tumor necrosis factor-alpha) and IL-1β (Interleukin-1 beta) and inhibited the expression of IL-10 (interleukin-10). NF-κB (nuclear factor kappa light chain enhancer of activated B cells) P65 inhibitor PDTC or TPCA1 lowed the increased levels of creatinine and BUN (blood urea nitrogen) in cisplatin-treated Tim-3 knockout mice serum and the increased cleavage of caspase 3 in sTim-3 and cisplatin-treated BUMPT cells. Moreover, sTim-3 enhanced mitochondrial oxidative stress in cisplatin-induced BUMPT cells, which can be mitigated by PDTC. These data indicate that Tim-3 may protect against renal injury by inhibiting NF-κB-mediated inflammation and oxidative stress.

Dihydromyricetin attenuates cisplatin-induced acute kidney injury by reducing oxidative stress, inflammation and ferroptosis

BackgroundCisplatin is effective against various types of cancers. However, its clinical application is limited owing to its adverse effects, especially acute kidney injury (AKI). Dihydromyricetin (DHM), a flavonoid derived from Ampelopsis grossedentata, has varied pharmacological activities. This research aimed to determine the molecular mechanism for cisplatin-induced AKI. MethodsA murine model of cisplatin-induced AKI (22 mg/kg, I.P.) and a HK-2 cell model of cisplatin-induced damage (30 μM) were established to evaluate the protective function of DHM. Renal dysfunction markers, renal morphology and potential signaling pathways were investigated. ResultsDHM decreased the levels of renal function biomarkers (blood urea nitrogen and serum creatinine), mitigated renal morphological damage, and downregulated the protein levels of kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin. It upregulated the expression levels of antioxidant enzymes (superoxide dismutase and catalase expression), nuclear factor-erythroid-2-related factor 2 (Nrf2) and its downstream proteins, including heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic (GCLC) and modulatory (GCLM) subunits, thus eventually reducing cisplatin-induced reactive oxygen species (ROS) production. Moreover, DHM partially inhibited the phosphorylation of the active fragments of caspase-8 and -3 and mitogen-activated protein kinase and restored glutathione peroxidase 4 expression, which attenuated renal apoptosis and ferroptosis in cisplatin-treated animals. DHM also mitigated the activation of NLRP3 inflammasome and nuclear factor (NF)-κB, attenuating the inflammatory response. In addition, it reduced cisplatin-induced HK-2 cell apoptosis and ROS production, both of which were blocked by the Nrf2 inhibitor ML385. ConclusionsDHM suppressed cisplatin-induced oxidative stress, inflammation and ferroptosis probably through regulating of Nrf2/HO-1, MAPK and NF-κB signaling pathways.

Synergistic Effect of Anethole and Platinum Drug Cisplatin against Oral Cancer Cell Growth and Migration by Inhibiting MAPKase, Beta-Catenin, and NF-κB Pathways.

Cisplatin is a common drug used to treat patients with oral squamous cell carcinoma. However, cisplatin-induced chemoresistance poses a major challenge to its clinical application. Our recent study has shown that anethole possesses an anti-oral cancer effect. In this study, we examined the combined effect of anethole and cisplatin on oral cancer therapy. Gingival cancer cells Ca9-22 were cultured in the presence of various concentrations of cisplatin with or without anethole. The cell viability/proliferation and cytotoxicity were evaluated, respectively, by MTT, Hoechst staining, and LDH assay, while colony formation was measured by crystal violet. Oral cancer cell migration was evaluated by the scratch method. Apoptosis, caspase activity, oxidative stress, MitoSOX, and mitochondrial membrane potential (ΔΨm) levels were evaluated by flow cytometry, and the inhibition of signaling pathways was investigated by Western blot. Our results show that anethole (3 µM) potentiates cisplatin-induced inhibition of cell proliferation and decreases the ΔΨm on Ca9-22 cells. Furthermore, drug combination was found to inhibit cell migration and enhanced cisplatin cytotoxicity. The combination of anethole and cisplatin potentiates cisplatin-induced oral cancer cell apoptosis through the activation of caspase, while we also found anethole and cisplatin to enhance the cisplatin-induced generation of reactive oxygen species (ROS) and mitochondrial stress. In addition, major cancer signaling pathways were inhibited by the combination of anethole and cisplatin such as MAPKase, beta-catenin, and NF-κB pathways. This study reports that the combination of anethole and cisplatin might provide a beneficial effect in enhancing the cisplatin cancer cell-killing effect, thus lowering the associated side effects.

Madecassoside ameliorates cisplatin-induced nephrotoxicity by inhibiting activation of the mitogen activated protein kinase pathway.

Nephrotoxicity is a major side effect of cisplatin. Apoptosis, oxidative stress, inflammation, and the MAPK signaling pathway activation are concerned with the pathophysiology of cisplatin-induced acute kidney injury (AKI). Madecassoside (MA), an active constituent of Centella asiatica, has anti-oxidative and anti-inflammatory effects. The present research aim to investigate the underlying protective mechanisms of MA on cisplatin nephrotoxicity. Pretreatment of mice with MA markedly ameliorated cisplatin-induced renal tubular cell injury evidenced by the improvement of kidney function and kidney morphology and blocked upregulation of kidney injury biomarkers (kidney injury molecule 1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL)). Cisplatin-induced renal cell apoptosis, inflammation, and oxidative stress were also prevented by MA treatment. Consistent with the in vivo results, MA pretreatment attenuated cisplatin-induced renal cell apoptosis, oxidative stress, and inflammation. Transcriptome analysis using RNA-sequencing suggested that the MAPK signaling pathway was the most affected, and MA could inhibit cisplatin-induced MAPK signaling pathway activation in vivo and in vitro. In summary, MA treatment ameliorated cisplatin-induced renal tubular damage possibly by decreasing activation of the MAPK signaling pathway, suggesting its potential for the treatment of AKI.

Ellagic acid ameliorates cisplatin-induced acute kidney injury by regulating inflammation and SIRT6/TNF-α signaling

Despite cisplatin has been widely used in the treatment of various cancers, the noteworthy nephrotoxicity greatly constrained its clinical value. For this reason, finding novel targeted therapies to attenuate the nephrotoxicity of cisplatin should be pretty significant. Our previous study found that histone deacetylase sirtuin 6 (SIRT6) could be an ideal target for the treatment of cisplatin-induced acute kidney injury. In this study, we explored the protective effects of ellagic acid, a natural polyphenol compound that activates SIRT6, on cisplatin-induced nephrotoxicity. Pre-treatment of ellagic acid attenuated cytotoxicity of cisplatin in primary renal cells and TCMK-1 cells. Moreover, ellagic acid ameliorated renal dysfunction, apoptosis and fibrosis induced by cisplatin in mice. Furthermore, ellagic acid reduced nephrotoxicity-associated inflammatory factor interleukin (IL)-1β and IL-6 expression both in vitro and in vivo. Mechanistically, ellagic acid reversed cisplatin-reduced SIRT6 expression and diminished cisplatin-induced tumor necrosis factor (TNF)-α expression. And SIRT6 knockdown abrogated the protective effects of ellagic acid on cisplatin-induced cell apoptosis, indicating the renal-protective effects of ellagic acid are mainly dependent on ellagic acid-mediated SIRT6 activation. Our results provide preclinical rationale for using ellagic acid as a feasible and promising agent to ameliorate cisplatin-induced acute kidney injury, and support ellagic acid as a potential adjunctive therapy for future cancer treatment.

Abstract 1684: Plasminogen activator inhibitor-1 (PAI-1) promotes cisplatin resistance in ovarian cancer cells by inhibiting ROS-mediated apoptosis and ferroptosis

Abstract Resistance to platinum-based chemotherapy is one of major causes of therapy failure and tumor recurrence in ovarian cancer patients. However, the molecular mechanism of platinum resistance is not fully understood. Here, we compared gene expression between cisplatin-sensitive and -resistant ovarian cancer cells using gene expression microarray analysis and found the significantly up-regulated expression of SERPINE1 encoding plasminogen activator inhibitor-1 (PAI-1), a serine protease regulating the fibrinolysis and extracelluar matrix, in cisplatin-resistant ovarian cancer cells. The correlation of high PAI-1 expression with low cisplatin sensitivity was confirmed in ovarian cancer cells. PAI-1 overexpression in ovarian cancer cells significantly decreased the sensitivity to cisplatin, whereas PAI-1 down-regulation by SERPINE1 siRNA or PAI-1 inhibitor increased cisplatin sensitivity. PAI-1 inhibited cisplatin-induced apoptosis in ovarian cancer cells by suppressing reactive oxygen species (ROS) production and DNA damage. PAI-1 also decreased cisplatin-induced ferroptosis through the upregulation of GPX4 levels. Furthermore, Kaplan-Meier survival analysis using TGGA data demonstrated that high PAI-1 expression was significantly associated with shorter platinum-free survival of patients with ovarian cancer. Collectively, these results illustrate that PAI-1 promotes cisplatin resistance in ovarian cancer cells by inhibiting ROS-mediated apoptosis and ferroptosis, suggesting that targeting PAI-1 increases the sensitivity to cisplatin in ovarian cancer. Citation Format: Mi Jeong Kwon, Ha Yeong Chae, So Young Lee, Shin Ung Kang, Tae Woong Jung, Soo Youn Cho, Jinil Han, Hyojin Jeong, Chang Ohk Sung, Young Kee Shin. Plasminogen activator inhibitor-1 (PAI-1) promotes cisplatin resistance in ovarian cancer cells by inhibiting ROS-mediated apoptosis and ferroptosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1684.

Amelioration of Cisplatin-Induced kidney injury by Arabinogalactan based on network pharmacology and molecular docking

Cisplatin is the most widely used anticancer chemotherapy drug at present. However, its severe nephrotoxic side effects limit the clinical application. This study aimed to investigate the potential protective mechanism of arabinogalactan (AG) on acute kidney injury (AKI) induced by cisplatin in mice. Firstly, 105 potential targets of AG were predicted by using the SwissTargetPrediction database, 25,183 kidney disease targets were obtained by searching 5 disease databases, and 100 cross-target targets were obtained by drawing a Venn diagram. We constructed the “AG-Key target” interaction network and PPI protein interaction network of cross-targets and screened out 21 core targets. Through the GO and KEGG enrichment analysis of the core targets, we can found that the core targets involved a total of 1254 biological functions and 56 signaling pathways, including the apoptosis signaling pathway. By establishing an animal model in vivo, we found that pretreatment with AG at doses of 200 and 400 mg/kg could decrease the kidney index, such as serum creatinine (CRE), and blood urea nitrogen (BUN) levels induced by cisplatin, and reduce the kidney histopathology injury. Importantly, AG could inhibit the formation of metaldehyde (MDA) and 4-hydroxynonenal (4-HNE) in the kidney tissues and reduce the oxidative stress injury induced by cisplatin. Meanwhile, AG also restored the expression of anti-apoptotic proteins Bcl-2 and Bcl-xL and decreased the expression of pro-apoptotic proteins Bax and Bad in cisplatin-induced renal tissues. Finally, AG could further reduce cisplatin-induced kidney cell apoptosis.

Repurposing of triamterene as a histone deacetylase inhibitor to overcome cisplatin resistance in lung cancer treatment.

Cisplatin is the core chemotherapeutic drug used for first-line treatment of advanced non-small cell lung cancer (NSCLC). However, drug resistance is severely hindering its clinical efficacy. This study investigated the circumvention of cisplatin resistance by repurposing non-oncology drugs with putative histone deacetylase (HDAC) inhibitory effect. A few clinically approved drugs were identified by a computational drug repurposing tool called "DRUGSURV" and evaluated for HDAC inhibition. Triamterene, originally indicated as a diuretic, was chosen for further investigation in pairs of parental and cisplatin-resistant NSCLC cell lines. Sulforhodamine B assay was used to evaluate cell proliferation. Western blot analysis was performed to examine histone acetylation. Flow cytometry was used to examine apoptosis and cell cycle effects. Chromatin immunoprecipitation was conducted to investigate the interaction of transcription factors to the promoter of genes regulating cisplatin uptake and cell cycle progression. The circumvention of cisplatin resistance by triamterene was further verified in a patient-derived tumor xenograft (PDX) from a cisplatin-refractory NSCLC patient. Triamterene was found to inhibit HDACs. It was shown to enhance cellular cisplatin accumulation and potentiate cisplatin-induced cell cycle arrest, DNA damage, and apoptosis. Mechanistically, triamterene was found to induce histone acetylation in chromatin, thereby reducing the association of HDAC1 but promoting the interaction of Sp1 with the gene promoter of hCTR1 and p21. Triamterene was further shown to potentiate the anti-cancer effect of cisplatin in cisplatin-resistant PDX in vivo. The findings advocate further clinical evaluation of the repurposing use of triamterene to overcome cisplatin resistance.

Liraglutide abrogates nephrotoxic effects of chemotherapies

Acute kidney injury (AKI) is a common clinical complication. Cisplatin (Cis) is an effective chemotherapeutic drug; however, its acute nephrotoxicity often limits its application. The role of liraglutide (Lir), an agonist of the glucagon-like peptide-1 receptor (GLP-1R), has recently attracted increasing attention beyond glycemic regulation. This study showed that Lir significantly ameliorated Cis-induced kidney dysfunction and renal damage. However, this renoprotective effect was partially abolished in GLP-1R knockout (GLP-1R-/-) mice. Furthermore, we synthesized Lir metabolites, GLP-1 (9−37) and GLP-1 (28−37), and found that they also exerted reno-protective effects that were not impaired in GLP-1R-/- mice. We also demonstrated that Lir and its metabolites reduced cisplatin-induced apoptosis in human renal tubular epithelial cells (HK-2). After silencing GLP-1R expression in HK-2 cells with small interfering ribose nucleic acid (siRNA), the protective effect of Lir on HK-2 cells was inhibited, while the protective effects of GLP-1 (9−37) and GLP-1 (28−37) were not affected. Additionally, we demonstrated that Lir and its metabolites inhibited Cis-induced high-mobility group box 1 (HMGB1) nuclear-cytoplasmic translocation and release, and reduced inflammatory cytokines and HMGB1 receptor expression. The exogenous use of recombinant HMGB1 (rHMGB1) dramatically weakened the protective effects of Lir and its metabolites. In conclusion, our study shows that Lir significantly attenuated Cis-induced AKI through GLP-1R dependent and independent pathways, mediated by inhibiting nuclear-cytoplasmic translocation and release of HMGB1. Lir and its metabolites may be effective drugs for treating cisplatin-induced nephrotoxicity.

Glutathione metabolism rewiring protects renal tubule cells against cisplatin-induced apoptosis and ferroptosis

ABSTRACTRenal proximal tubular cells are highly vulnerable to different types of assaults during filtration and reabsorption, leading to acute renal dysfunction and eventual chronic kidney diseases (CKD). The chemotherapeutic drug cisplatin elicits cytotoxicity causing renal tubular cell death, but its executing mechanisms of action are versatile and elusive. Here, we show that cisplatin induces renal tubular cell apoptosis and ferroptosis by disrupting glutathione (GSH) metabolism. Upon cisplatin treatment, GSH metabolism is impaired leading to GSH depletion as well as the execution of mitochondria-mediated apoptosis and lipid oxidation-related ferroptosis through activating IL6/JAK/STAT3 signaling. Inhibition of JAK/STAT3 signaling reversed cell apoptosis and ferroptosis in response to cisplatin induction. Using a cisplatin-induced acute kidney injury (CAKI) mouse model, we found that inhibition of JAK/STAT3 significantly mitigates cisplatin nephrotoxicity with a reduced level of serum BUN and creatinine as well as proximal tubular distortion. In addition, the GSH booster baicalein also reclaims cisplatin-induced renal tubular cell apoptosis and ferroptosis as well as the in vivo nephrotoxicity. In conclusion, cisplatin disrupts glutathione metabolism, leading to renal tubular cell apoptosis and ferroptosis. Rewiring glutathione metabolism represents a promising strategy for combating cisplatin nephrotoxicity.

TRPM2 protects against cisplatin-induced acute kidney injury and mitochondrial dysfunction via modulating autophagy.

Background: Cisplatin is a widely used anti-tumor agent but its use is frequently limited by nephrotoxicity. Transient receptor potential melastatin 2 (TRPM2) is a non-selective cation channel which is generally viewed as a sensor of oxidative stress, and increasing evidence supports its link with autophagy, a critical process for organelle homeostasis. Methods: Cisplatin-induced cell injury and mitochondrial damage were both assessed in WT and Trpm2-knockout mice and primary cells. RNA sequencing, immunofluorescence staining, immunoblotting and flowcytometry were applied to interpret the mechanism of TRPM2 in cisplatin nephrotoxicity. Results: Knockout of TRPM2 exacerbates renal dysfunction, tubular injury and cell apoptosis in a model of acute kidney injury (AKI) induced by treatment with cisplatin. Cisplatin-caused tubular mitochondrial damage is aggravated in TRPM2-deficient mice and cells and, conversely, alleviated by treatment with Mito-TEMPO, a mitochondrial ROS scavenger. TRPM2 deficiency hinders cisplatin-induced autophagy via blockage of Ca2+ influx and subsequent up-regulation of AKT-mTOR signaling. Consistently, cisplatin-induced tubular mitochondrial damage, cell apoptosis and renal dysfunction in TRPM2-deficient mice are mitigated by treatment with a mTOR inhibitor. Conclusion: Our results suggest that the TRPM2 channel plays a protective role in cisplatin-induced AKI via modulating the Ca2+-AKT-mTOR signaling pathway and autophagy, providing novel insights into the pathogenesis of kidney injury.

Static Magnetic Fields Protect against Cisplatin-Induced Kidney Toxicity.

Cisplatin is one of the most widely used anti-cancer drugs that can effectively inhibit the growth of multiple types of cancer. However, its clinical application is limited by its severe side effects, especially kidney toxicity, caused by cisplatin-induced oxidative stress, inflammation and kidney cell apoptosis. Here, we found that moderate (a few hundred mT) quasi-uniform static magnetic fields (SMFs) could inhibit cisplatin-induced renal proximal tubular cell death, especially the vertically downward direction SMF. RNA-seq experiments demonstrate that SMFs induced differential gene expressions that are closely associated with oxidative stress, apoptosis, cytokine production, transmembrane transport and DNA repair. In vivo experiments show that SMFs can reduce cisplatin-induced kidney injury in cisplatin-administrated tumor-bearing mice by reducing oxidative stress, inflammation and cell apoptosis. Furthermore, high-dose cisplatin-induced acute nephrotoxicity can be effectively alleviated by SMF treatment of as little as one day, which significantly reduced the reactive oxygen species levels in kidneys and prolonged the mice's survival. Moreover, the concentration of cisplatin in the kidney was significantly attenuated in SMF-treated mice. Therefore, our study demonstrates the effects of moderate SMFs as a novel physical method to reduce oxidative stress, and revealed their future potential to be used against cisplatin-induced kidney toxicity in cancer treatment.

Kidney Mesenchymal stem cells alleviate cisplatin-induced kidney injury and apoptosis in rats

ObjectiveThis experiment was designed to demonstrate Mesenchymal stem cells (MSCs) derived from kidney can alleviate cisplatin-induced kidney injury and renal cell apoptosis through paracrine pathway. MethodsFirstly, MSCs were isolated from kidney of young rats, and their surface-specific markers were identified by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and immunofluorescence staining. Self-renewal ability of Kidney Mesenchymal Stem Cells (KMSCs) was observed by cell counting and 5-Bromo-2′-deoxyuridine (BrdU) fluorescence staining. KMSCs at logarithmic growth stage were traced and injected into rat through tail vein. ResultsThe results showed that KMSCs homed in the kidney tissues, decreased the secretion of inflammatory factors (CRP, TNFα, IL-1β, IL-6), and alleviated renal function. Hematoxylin and Eosin (H＆E), Masson and Periodic Acid-silver Methenamine (PASM) staining showed that KMSCs could alleviate pathological damage in rats. Terminal Deoxynucleotidyl Transferase mediated dUTP Nick-End Labeling (TUNEL) assay showed that KMSCs could reduce the apoptosis of rat kidney cells induced by cisplatin. Finally, Immunohistochemistry (IHC) results showed that cisplatin could induce higher expression of the pro-apoptotic protein Bax and lower expression of anti-apoptotic Bcl-2 in kidney tissues. However, KMSCs could reverse the pro-apoptotic effect of cisplatin on kidney cells and improve the survival rate of rats. ConclusionsIn conclusion, KMSCs were successfully isolated from kidney tissues, and KMSCs have therapeutic effects on rat kidney injury induced by cisplatin.

Memantine enhances the cisplatin-induced apoptosis in A2780 ovarian cancer cells via CyclinD1 and hTERT inhibition

Cisplatin is the first-line treatment for ovarian cancer. Therefore, the use of effective compounds with synergistic effects can be considered a new strategy. Memantine is an NMDA receptors blocker which is overexpressed in cancers, including ovarian cancer and thus can be an efficient adjunct in cancer treatment. In this study, the MTT test, Flow cytometry, and DAPI staining was used to examine the combined effect of cisplatin with memantine. A study on Cyclin D1 and hTERT expression levels were conducted by qRT-PCR, and also cell cycle study of treated cells was performed. Our findings demonstrated that memantine enhances cytotoxicity in A2780 ovarian cancer cells. Apoptosis was also enhanced in cells treated with the combination of memantine and cisplatin. Memantine reduced the expression of Cyclin D1 and hTERT in A2780 cells and decreased the number of cancer cells in the cell cycle's growth and division phase. Our study suggests that memantine can be considered a potent adjuvant in the treatment of ovarian cancer.