Doxorubicin Action on Mitochondria: Relevance to Osteosarcoma Therapy?

The Role of Oxidative Stress in Tumorigenesis and Progression

Oxidative stress refers to the imbalance between the production of reactive oxygen species (ROS) and the endogenous antioxidant defense system. Its involvement in cell senescence, apoptosis, and series diseases has been demonstrated. Advances in carcinogenic research have revealed oxidative stress as a pivotal pathophysiological pathway in tumorigenesis and to be involved in lung cancer, glioma, hepatocellular carcinoma, leukemia, and so on. This review combs the effects of oxidative stress on tumorigenesis on each phase and cell fate determination, and three features are discussed. Oxidative stress takes part in the processes ranging from tumorigenesis to tumor death via series pathways and processes like mitochondrial stress, endoplasmic reticulum stress, and ferroptosis. It can affect cell fate by engaging in the complex relationships between senescence, death, and cancer. The influence of oxidative stress on tumorigenesis and progression is a multi-stage interlaced process that includes two aspects of promotion and inhibition, with mitochondria as the core of regulation. A deeper and more comprehensive understanding of the effects of oxidative stress on tumorigenesis is conducive to exploring more tumor therapies.

The known unknowns of mitochondrial carcinogenesis: de novo NUMTs and intercellular mitochondrial transfer

The translocation of mitochondrial DNA (mtDNA) sequences into the nuclear genome, resulted in the occurrence of nuclear sequences of mitochondrial origin (NUMTs) which can be detected in nearly all sequenced eukaryotes. However, de novo mtDNA insertions can contribute to the development of pathological conditions including cancer. Recent data indicate that de novo mtDNA translocation into chromosomes can occur due to genotoxic influence of DNA double-strand break-inducing environmental mutagens. This confirms the hypothesis of the involvement of genome instability in the occurrence of mtDNA fragments in chromosomes. Mounting evidence indicates that mitochondria can be transferred from normal cells to cancer cells and recover cellular respiration. These exchanged mitochondria can facilitate cancer progression and metastasis. This review article provides a comprehensive overview of the potential carcinogenicity of mtDNA insertions, and the relevance of mtDNA escape in cancer progression, metastasis, and treatment resistance in humans. Potential molecular targets involved in mtDNA escape and exchange of mitochondria that can be of possible clinical benefits are presented and discussed. Understanding these processes could lead to improved diagnostic approaches, novel therapeutic strategies, and a deeper understanding of the intricate relationship between mitochondria, nuclear DNA, and cancer biology.

Resveratrol may dose-dependently modulate nephrin and OTULIN levels in a doxorubicin-induced nephrotoxicity model

One of the most important side effects of Doxorubicin (DOX), a chemotherapeutic agent, is nephrotoxicity. The purpose of this study is to determine whether different doses of natural polyphenol Resveratrol (RSV) show antioxidative, anti-inflammatory or antiapoptotic effects in kidney tissue in DOX-induced nephrotoxicity and to detect how nephrin and OTULIN levels are affected in this process. A total of six equal groups made up of the 42 Sprague-Dawley rats utilized in the study (n = 7) were randomly assigned. Except for the control group (no treatment), all treatments were given intraperitoneally to the DOX (15 mg/kg), DOX + RSV I (15 mg/kg DOX+ 1 mg/kg/day RSV), DOX + RSV II (15 mg/kg DOX+ 5 mg/kg/day RSV), RSV I and RSV II groups. Kidney tissues taken from rats sacrificed on the fifteenth day were analyzed biochemically, histologically and immunohistochemically. Accordingly, it was determined that nephrin and OTULIN levels decreased in kidney tissue in DOX-induced nephrotoxicity. Furthermore, DOX caused oxidative stress, inflammation, and apoptosis, as well as histopathological changes in kidney tissue. However, it was observed that DOX-induced changes were regulated by RSV application. RSV was demonstrated to have antioxidant, anti-inflammatory and anti-apoptotic properties in dose-dependent DOX-induced nephrotoxicity. RSV may exert nephroprotective effects by modulating DOX-induced altered nephrin and OTULIN levels.

N-(2-hydroxy phenyl) acetamide ameliorate inflammation and doxorubicin-induced nephrotoxicity in rats

Doxorubicin (DOX) is an anthracyclin antibiotic used for the treatment of various cancers. Nephrotoxicity is among the serious side effects of DOX, therefore, DOX-induced nephrotoxic model has been widely used to study nephropathies. The objectives of this study is to investigate the possible anti-inflammatory and nephroprotective effects of salicylic acid derivative, N-(2-hydroxy phenyl) acetamide (NA-2), in a rat model of DOX-induced nephrotoxicity. The in vitro anti-inflammatory potential of NA-2 was manifested by whole blood oxidative burst and nitric oxide (NO) assays with no toxicity on normal human fibroblast (BJ) cells, human embryonic kidney (HEK-293) cells, and normal monkey kidney epithelial (Vero) cells. The in vivo study included five groups: Normal control, DOX (6 mg/kg DOX-i.v.via tail vein), NA-2 treated control-i.p., NA-2/DOX treated-i.p., and prednisolone/DOX treated. After 7 days of DOX administration, rats with urinary protein level of >50 mg/kg/day were selected. Treatment group rats received i.p. doses of NA-2 (10 mg/kg/day) for 3 weeks with weekly monitoring of urinary protein excretion and body weights. mRNA expression of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, monocyte chemoattractant protein (MCP)-1, and kidney injury molecule (KIM)-1 was analyzed by quantitative polymerase chain reaction (qPCR). Protein expressions were analyzed by immunohistochemistry. NA-2 attenuated DOX-induced changes in serum and urine levels, and improved inflammatory profile of the renal tissue. Histopathological findings revealed protective effects of NA-2 showing lesser lesions. We conclude that NA-2 is able to protect against DOX-induced renal damage functionally, biochemically and histopathologically with corresponding improvement in the kidney inflammatory profile.

Malignant transformation of an aneurysmal bone cyst of the femoral neck: A case report

Aneurysmal bone cyst (ABC) is a benign, distending, osteolytic and locally aggressive bone tumor that is mostly associated with trauma. Approximately 1% of bone tumors are ABCs, which are most prevalent in adolescents and are usually detected in the spine and long tubular bones. The diagnosis of ABC mainly relies on histopathology, malignant transformation is rare, and the chance of malignancy increases if there are multiple recurrences. Due to the rarity of reports of malignant transformation of ABCs into osteosarcoma, there is still considerable debate on the appropriate treatment strategy. The current paper presents a case of aneurysmal bone cyst malignant to osteosarcoma and the therapeutic measures to provide expertise for the diagnosis and treatment of ABCs that are malignant to osteosarcoma.

ADCK1 is a potential therapeutic target of osteosarcoma

We here showed that ADCK1 (AarF domain-containing kinase 1), a mitochondrial protein, is upregulated in human osteosarcoma (OS) tissues and OS cells. In primary and established OS cells, ADCK1 shRNA or CRISPR/Cas9-induced ADCK1 knockout (KO) remarkably inhibited cell viability, proliferation and migration, and provoked apoptosis activation. Conversely, ectopic ADCK1 overexpression exerted pro-cancerous activity by promoting OS cell proliferation and migration. ADCK1 depletion disrupted mitochondrial functions in OS cells and induced mitochondrial membrane potential reduction, ATP depletion, reactive oxygen species production. Significantly, ADCK1 silencing augmented doxorubicin-induced apoptosis in primary OS cells. mTOR activation is important for ADCK1 expression in OS cells. The mTOR inhibitors, rapamycin and AZD2014, as well as mTOR shRNA, potently decreased ADCK1 expression in primary OS cells. In nude mice, the growth of subcutaneous pOS-1 xenografts was largely inhibited when bearing ADCK1 shRNA or ADCK1 KO construct. Moreover, ADCK1 KO largely inhibited pOS-1 xenograft in situ growth in proximal tibia of nude mice. ADCK1 depletion, apoptosis activation and ATP reduction were detected in pOS-1 xenografts bearing ADCK1 shRNA or ADCK1 KO construct. Together, the mitochondrial protein ADCK1 is required for OS cell growth and is a novel therapeutic target of OS.

Cinobufagin inhibits tumor progression and reduces doxorubicin resistance by enhancing FOXO1-mediated transcription of FCGBP in osteosarcoma

ETHNOPHARMACOLOGICAL RELEVANCE

Cinobufagin (Huachansu), an aqueous extract from the dried skin of the toad Bufo bufo gargarizans Cantor (frog skin), is a biologically active ingredient of a traditional Chinese medicine cinobufacini that can treat multiple bone pathological conditions such as bone pain, bone tumors, and osteosarcoma.

AIM OF THE STUDY

The study aimed to explore the roles and molecular mechanisms of cinobufagin underlying osteosarcoma development and doxorubicin (ADR) resistance.

MATERIALS AND METHODS

Cell viability, migration, and invasion were examined by CCK-8, wound healing, and Transwell invasion assays, respectively. RNA sequencing analysis was performed in MNNG/HOS cells treated with or without cinobufagin. The relationships of cinobufagin, forkhead box O1 (FOXO1), and Fc fragment of IgG binding protein (FCGBP) were examined by luciferase reporter, immunofluorescence (IF), RT-qPCR, and chromatin immunoprecipitation (ChIP) assays together with weighted gene co-expression network analysis (WGCNA) analysis. Epithelial-mesenchymal transition (EMT) marker levels were examined through the Western blot assay. The function and molecular basis of cinobufagin in osteosarcoma were further investigated by mouse xenograft experiments.

RESULTS

Cinobufagin reduced cell viability, weakened ADR resistance, and inhibited cell migration/invasion/EMT in osteosarcoma cells. Cinobufagin enhanced FOXO1-mediated transcription of downstream genes including FCGBP. FCGBP knockdown partly abrogated the effect of cinobufagin on osteosarcoma cell development. Cinobufagin inhibited the growth of mouse osteosarcoma xenografts in vivo. Cinobufagin reduced the expression of Ki-67 and MMP9 and facilitated caspase-3 expression in osteosarcoma xenografts.

CONCLUSION

Cinobufagin suppressed tumor progression and reduced ADR resistance by potentiating FOXO1-mediated transcription of FCGBP in osteosarcoma.

Circ-LTBP1 is involved in doxorubicin-induced intracellular toxicity in cardiomyocytes via miR-107/ADCY1 signal

Although doxorubicin (DOX) is a broad-spectrum and anthracycline chemotherapeutic agent, cardiotoxicity limits its clinical application. Therefore, it is meant to prevent the clinical side effects of DOX. Human cardiomyocyte-like AC16 cells were treated with DOX to induce intracellular toxicity. AC16 cell viability was determined by Cell Counting Kit 8 and 5-ethynyl-2'-deoxyuridine assays. The tumor necrosis factor-α and interleukin-6 abundances were quantified by matched kits. The apoptosis rate was measured by flow cytometry. Western blot analysis was conducted to measure the protein expression levels in AC16 cells. Oxidative stress was analyzed by measuring superoxide dismutase and malondialdehyde production. The quantitative real-time polymerase chain reaction was conducted to assess the expression levels of circ-latent transforming growth factor-beta binding protein-1 (circ-LTBP1), microRNA-107 (miR-107), and Adenylate cyclase 1 (ADCY1) expression in AC16 cells. The interaction relationship among circ-LTBP1, miR-107, and ADCY1 was verified by dual-luciferase reporter and RNA immunoprecipitation assays. As a result, treatment with DOX induced the proliferation inhibition, inflammation, apoptosis, and oxidative stress in AC16 cells, which were rescued by circ-LTBP1 inhibition or miR-107 upregulation. MiR-107 was confirmed as a target of circ-LTBP1, and inhibition of circ-LTBP1-mediated effects on DOX-stimulated cells were abolished by downregulation of miR-107. Circ-LTBP1 mediated ADCY1 expression by sponging miR-107 in AC16 cells. The upregulation of miR-107 increased cell proliferation and inhibited inflammation, apoptosis, and oxidative stress in DOX-stimulated cells through downregulation of ADCY1. Circ-LTBP1 was found to enhance DOX-induced effects on proliferation inhibition, inflammation, apoptosis, and oxidative stress in AC16 cells through competitively sponging miR-107 and elevating ADCY1.

Schisandrin B suppresses osteosarcoma lung metastasis in vivo by inhibiting the activation of the Wnt/β‑catenin and PI3K/Akt signaling pathways

Osteosarcoma (OS) is the most common malignant bone tumor worldwide and is associated with a poor prognosis, often being accompanied by lung metastasis at an early stage. At present, there are several side-effects associated with the OS clinical treatment of OS, with the treatment effects often being unsatisfactory. Thus, there is an urgent need for the development of safe and effective novel drugs for the treatment of OS. Schisandrin B (Sch B) has been previously demonstrated to exhibit antitumor properties. The present study was focused on the effects of Sch B on OS cells (143B, MG63, Saos2 and U2OS) in vitro and in vivo, and also on its possible antitumor mechanisms. In cell experiments, it was revealed that Sch B inhibited OS cell proliferation, migration and invasion, and increased OS cell apoptosis. As regards its biosafety, no notable effects of Sch B on the vitality of normal cells were observed. Mechanistically, it was demonstrated that Sch B blocked OS cell proliferation in the G₁ phase. Subsequently, by using established animal models, it was revealed that Sch B significantly inhibited OS growth and lung metastasis in vivo. In summary, the results of the present study revealed that Sch B inhibited OS cell proliferation, migration and invasion, and promoted apoptosis via the inhibition of the Wnt/β-catenin and PI3K/Akt signaling pathways, without causing any noticeable toxic effects on healthy cells at the therapeutic concentrations used. These findings suggest that Sch B has potential for use as a novel agent for the clinical treatment of OS.

Regucalcin ameliorates Doxorubicin-induced cytotoxicity in Cos-7 kidney cells and translocates from the nucleus to the mitochondria

Doxorubicin (DOX) is a potent anti-cancer drug, which can have unwanted side-effects such as cardiac and kidney toxicity. A detailed investigation was undertaken of the acute cytotoxic mechanisms of DOX on kidney cells, using Cos-7 cells as kidney cell model. Cos-7 cells were exposed to DOX for a period of 24 hours over a range of concentrations and the LC50 was determined to be 7µM. Further investigations showed that cell death was mainly via apoptosis involving Ca2+ and caspase 9, in addition to autophagy. Regucalcin (RGN), a cytoprotective protein found mainly in liver and kidney tissues, was overexpressed in Cos-7 cells and shown to protect against DOX-induced cell death. Subcellular localization studies in Cos-7 cells showed RGN to be strongly correlated with the nucleus. However, upon treatment with DOX for 4 hours, which induced membrane blebbing in some cells, the localization appeared to be correlated more with the mitochondria in these cells. It is yet to be determined whether this translocation is part of the cytoprotective mechanism or a consequence of chemically-induced cell stress.

A modular, reversible sealing, and reusable microfluidic device for drug screening

Preclinical tests for evaluating potential drug candidates using conventional protocols can be exhaustive and high-cost processes. Microfluidic technologies that can speed up this process and allow fast screening of drugs are promising alternatives. This work presents the design, concept, and operational conditions of a simple, modular, and reversible sealing microdevice useful for drug screening. This microdevice allows for the operation of 4 parallel simultaneous conditions and can also generate a diffusive concentration gradient in sextuplicates. We used laminated polydimethylsiloxane (PDMS_LAM) and glass as building materials as proof of concept. The PDMS_LAM parts can be reused since they can be easily sterilized. We cultured MCF-7 (Michigan Cancer Foundation-7) breast cancer cells. Cells were exposed to a doxorubicin diffusive concentration gradient for 3 h. They were monitored by automated microscopy, and after data processing, it was possible to determine cell viability as a function of doxorubicin concentration. The reversible sealing enabled the recovery of the tested cells and image acquisition. Therefore, this microdevice is a promising tool for drug screening that allows assessing the cellular behavior in dynamic conditions and the recovery of cells for afterward processing and imaging.

MiR-325 Promotes Oxaliplatin-Induced Cytotoxicity Against Colorectal Cancer Through the HSPA12B/PI3K/AKT/Bcl-2 Pathway

BACKGROUND

Oxaliplatin is one of the most effective chemotherapeutic drugs used for the treatment of colorectal cancer (CRC). However, intervention that attenuates the resistance of oxaliplatin is still required in the treatment of CRC.

AIMS

To investigate the role of miR-325 in changing the oxaliplatin sensitivity to CRC cells.

METHODS

Expression of miR-325 in colorectal cancer tissues and cell lines was measured by using qRT-PCR analysis. Cytotoxicity of oxaliplatin to control or miR-325-overexpressed HT29 and SW480 cells was evaluated by CCK-8 assays. Luciferase reporter assay was used to confirm the regulation of miR-325 on HSPA12B. Flow cytometry was performed to detect the mitochondrial membrane potential and cell apoptosis.

RESULTS

Expression of miR-325 was decreased in colorectal cancer tissues and cell lines. However, overexpression of miR-325 can decrease the 50% inhibiting concentration of oxaliplatin to colorectal cancer cell lines HT29 and SW480. Mechanically, we confirmed that miR-325 targeted HSPA12B in colorectal cancer. Therefore, overexpression of miR-325 inhibited the phosphorylation of PI3K and AKT and decreased the expression of Bcl-2 to promote the oxaliplatin-induced mitochondrial apoptosis in colorectal cancer.

CONCLUSIONS

MiR-325 sensitizes the colorectal cancer cells to oxaliplatin-induced cytotoxicity through the HSPA12B/PI3K/AKT/Bcl-2 pathway.

Melittin inhibits lung metastasis of human osteosarcoma: Evidence of wnt/β-catenin signaling pathway participation

Melittin is a major active peptide component of bee venom that has been demonstrated to show anti-tumor effects. Osteosarcoma is a type of bone tumor with a high degree of malignancy, and metastasis is the main challenge of osteosarcoma therapy. This study aimed to investigate the role of melittin in the lung metastasis of osteosarcoma. 143 B cells were treated with different concentrations of melittin in vitro. Wound-healing and transwell assays were performed to determine the cell migration and invasion potential. Quantitative real-time PCR and Western blot experiments were performed to evaluate the expression levels of Wnt/β-catenin signaling pathway-related factors after treatment with melittin. The orthotopic implantation model and hematoxylin-eosin staining were used to investigate the effect of melittin treatment on tumor formation and lung metastasis. Immunohistochemical staining and Western blot experiments were performed to indicate the melittin-mediated expression changes in Wnt/β-catenin signaling pathway-related factors. The cell migration and invasion potential were observed to be inhibited in a dose-dependent manner upon treatment with melittin. Treatment with medium and high concentrations of melittin attenuated the mRNA and protein expression of LRP5, β-catenin, MMP-2, cyclin D, c-Myc, survivin, MMP-9, and VEGF genes in vitro. Melittin significantly inhibited the growth of tibia xenografts in nude mice and decreased the number of lung metastatic nodules. Consistent with the results observed in vitro, treatment with melittin at medium and high concentrations attenuated the expression of Wnt/β-catenin signaling pathway-related factors in vivo. In vitro, Wnt/β-catenin signaling pathway was involved in Melittin-mediated -migration and invasion potential of 143 B cells. Similarly, as observed in the in vivo experiments, Wnt/β-catenin signaling pathway was also associated with the role of melittin on lung metastasis of osteosarcomas.

Cold Atmospheric Plasma: A New Strategy Based Primarily on Oxidative Stress for Osteosarcoma Therapy

Osteosarcoma is the most common primary bone tumor, and its first line of treatment presents a high failure rate. The 5-year survival for children and teenagers with osteosarcoma is 70% (if diagnosed before it has metastasized) or 20% (if spread at the time of diagnosis), stressing the need for novel therapies. Recently, cold atmospheric plasmas (ionized gases consisting of UV-Vis radiation, electromagnetic fields and a great variety of reactive species) and plasma-treated liquids have been shown to have the potential to selectively eliminate cancer cells in different tumors through an oxidative stress-dependent mechanism. In this work, we review the current state of the art in cold plasma therapy for osteosarcoma. Specifically, we emphasize the mechanisms unveiled thus far regarding the action of plasmas on osteosarcoma. Finally, we review current and potential future approaches, emphasizing the most critical challenges for the development of osteosarcoma therapies based on this emerging technique.

Antioxidant and Anti-Inflammatory Effects of Crocin Ameliorate Doxorubicin-Induced Nephrotoxicity in Rats

Doxorubicin is a drug that belongs to the anthracycline antibiotics. Nephrotoxicity is one of the serious side effects of doxorubicin treatment. Crocin, which is one of the most bioactive components of saffron, has antioxidant, anti-inflammatory, and antitumor effects. The current study was aimed at investigating the possible protective effects of crocin against doxorubicin-induced nephrotoxicity to elucidate the underlying mechanism of this effect. The study included four groups, six rats in each group: normal control, crocin control, doxorubicin, and crocin/doxorubicin. Doxorubicin and crocin/doxorubicin groups received intraperitoneal injections of doxorubicin (3.5 mg/kg twice weekly for 3 weeks). Rats in the crocin control group and the crocin/doxorubicin group were treated with intraperitoneal injections of crocin (100 mg/kg body weight per day) for 3 weeks. Biomarkers of kidney function and oxidative stress as well as the abundance of mRNA for nuclear factor-κβ and inducible nitric oxide synthase were evaluated. In addition, the abundance of cyclooxygenase 2 and tumor necrosis factor α immunoreactivity was evaluated. Crocin treatment had renoprotective effects manifested by significant improvement in kidney function as well as a reduction in the abundance of biomarkers of oxidative stress markers and inflammatory mediators. In conclusion, crocin has a protective effect against doxorubicin-induced nephrotoxicity in rats by serving as an antioxidant and attenuating the expression of NF-κB, iNOS, COX2, and TNFα.

miR-520b Inhibits IGF-1R to Increase Doxorubicin Sensitivity and Promote Cell Apoptosis in Breast Cancer

Doxorubicin (DOX) is currently one of the most widely used and effective drugs for the treatment of breast cancer, but drug resistance in breast cancer often leads to poor efficacy. MicroRNAs (miRNAs) are involved in the development and progression of various tumors and increasing number of studies have confirmed that abnormal miR-520b expression is closely associated breast cancer. We analyzed the clinical features, including miR-520b, of 30 patients with breast cancer. Further, we analyzed the interaction between miR-520b and insulin-like growth factor 1 receptor (IGF-1R) in breast cancer cell. miR-520b expression was significantly increased in chemotherapy-sensitive patients and was positively correlated with the chemotherapeutic efficacy in breast cancer. Cell proliferation assay confirmed that miR-520b promotes DOX-induced breast cancer cell apoptosis by regulating the PI3K/AKT signaling pathway. Moreover, bioinformatics method and dual luciferase reporter assay demonstrated that miR-520b negatively regulates IGF-1R, and IGF-1R overexpression and enhanced activity are closely associated with tumor development, progression, metastasis, and chemotherapy resistance. Similarly, cell proliferation assay showed that IGF-1R is negatively correlated with the efficacy of DOX chemotherapy and affects cell apoptosis mediated by the PI3K/AKT signaling pathway. On the contrary, miR-520b can downregulate the expression of IGF-1R. miR-520b increases DOX sensitivity and promotes cell apoptosis in breast cancer by inhibiting IGF-1R expression by the PI3K/AKT signaling pathway.