Two distinct modes of cell death induced by doxorubicin: apoptosis and cell death through mitotic catastrophe accompanied by senescence-like phenotype

Mechanistic insights into carvedilol's potential protection against doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is an anthracycline chemotherapy drug widely employed in the treatment of various cancers, known for its potent antineoplastic properties but often associated with dose-dependent cardiotoxicity, limiting its clinical use. This review explores the complex molecular details that determine the heart-protective effectiveness of carvedilol in relation to cardiotoxicity caused by DOX. The harmful effects of DOX on heart cells could include oxidative stress, DNA damage, iron imbalance, disruption of autophagy, calcium imbalance, apoptosis, dysregulation of topoisomerase 2-beta, arrhythmogenicity, and inflammatory responses. This review carefully reveals how carvedilol serves as a strong protective mechanism, strategically reducing each aspect of cardiac damage caused by DOX. Carvedilol's antioxidant capabilities involve neutralizing free radicals and adjusting crucial antioxidant enzymes. It skillfully manages iron balance, controls autophagy, and restores the calcium balance essential for cellular stability. Moreover, the anti-apoptotic effects of carvedilol are outlined through the adjustment of Bcl-2 family proteins and activation of the Akt signaling pathway. The medication also controls topoisomerase 2-beta and reduces the renin-angiotensin-aldosterone system, together offering a thorough defense against cardiotoxicity induced by DOX. These findings not only provide detailed understanding into the molecular mechanisms that coordinate heart protection by carvedilol but also offer considerable potential for the creation of targeted treatment strategies intended to relieve cardiotoxicity caused by chemotherapy.

Photoactive metabolite mediated photodynamic therapy of Rhabdomyosarcoma cell lines using medicinal plants and Doxorubicin co-treatments

BACKGROUND

Medicinal plant-mediated combinational therapies have gained importance globally due to minimal side effects and enhanced treatment outcomes compared to single-drug modalities. We aimed to analyze the cytotoxic potential of each conventional treatment i.e., photodynamic therapy (PDT), chemotherapy (doxorubicin hydrochloride; Dox-HCl) with or without various concentrations of medicinal plant extracts (PE) on soft tissue cancer Rhabdomyosarcoma (RD) cell line.

METHODS

The Rhabdomyosarcoma (RD) cell line was cultured and treated with Photosensitizer (Photosense (AlPc4)), Chemo (Dox-HCl), and their combinations with different concentrations of each plant extract i.e., Thuja occidentalis, Moringa oleifera, Solanum surattense. For the source of illumination, a Diode laser (λ = 630 nm ± 1 nm, Pmax = 1.5 mW) was used. Photosensitizer uptake time (∼ 45 min) was optimized through spectrophotometric measurements (absorption spectroscopy). Drug response of each treatment arm was assessed post 24 h of administration using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5- 5-diphenyl-2 H- tetrazolium bromide (MTT) assay.

RESULTS

PE-mediated Chemo-Photodynamic therapy (PDT) exhibited synergistic effects (CI < 1). Moreover, Rhabdomyosarcoma culture pretreated with various plant extracts for 24 h exhibited significant inhibition of cell viability however most effective outcomes were shown by low and high doses of Moringa oleifera compared to other plant extracts. Post low doses treated culture with all plant extracts followed by PDT came up with more effectiveness when compared to all di-therapy treatments.

CONCLUSION

The general outcome of this work shows that the ethanolic plant extracts (higher doses) promote the death of cancerous cells in a dose-dependent way and combining Dox-HCl and photo-mediated photodynamic therapy can yield better therapeutic outcomes.

Research progress on morphology and mechanism of programmed cell death

Programmed cell death (PCD) is a basic process of life that is closely related to the growth, development, aging and disease of organisms and is one of the hotspots of life science research today. PCD is a kind of genetic control, autonomous and orderly important cell death that involves the activation, expression, and regulation of a series of genes. In recent years, with the deepening of research in this field, new mechanisms of multiple PCD pathways have been revealed. This article reviews and summarizes the multiple PCD pathways that have been discovered, analyses and compares the morphological characteristics and biomarkers of different types of PCD, and briefly discusses the role of various types of PCD in the diagnosis and treatment of different diseases, especially malignant tumors.

Transformer-based spatial-temporal detection of apoptotic cell death in live-cell imaging

Intravital microscopy has revolutionized live-cell imaging by allowing the study of spatial-temporal cell dynamics in living animals. However, the complexity of the data generated by this technology has limited the development of effective computational tools to identify and quantify cell processes. Amongst them, apoptosis is a crucial form of regulated cell death involved in tissue homeostasis and host defense. Live-cell imaging enabled the study of apoptosis at the cellular level, enhancing our understanding of its spatial-temporal regulation. However, at present, no computational method can deliver robust detection of apoptosis in microscopy timelapses. To overcome this limitation, we developed ADeS, a deep learning-based apoptosis detection system that employs the principle of activity recognition. We trained ADeS on extensive datasets containing more than 10,000 apoptotic instances collected both in vitro and in vivo, achieving a classification accuracy above 98% and outperforming state-of-the-art solutions. ADeS is the first method capable of detecting the location and duration of multiple apoptotic events in full microscopy timelapses, surpassing human performance in the same task. We demonstrated the effectiveness and robustness of ADeS across various imaging modalities, cell types, and staining techniques. Finally, we employed ADeS to quantify cell survival in vitro and tissue damage in mice, demonstrating its potential application in toxicity assays, treatment evaluation, and inflammatory dynamics. Our findings suggest that ADeS is a valuable tool for the accurate detection and quantification of apoptosis in live-cell imaging and, in particular, intravital microscopy data, providing insights into the complex spatial-temporal regulation of this process.

2D MOF-enhanced SPR detector based on tunable supramolecular probes for direct and sensitive detection of DOX in serum

Therapeutic drug monitoring of doxorubicin (DOX) is important to study pharmacokinetics in patients undergoing chemotherapy for reduction of side effects and improve patient survival by rationally controlling the dose of DOX. A fast and ultra-sensitive surface plasmon resonance (SPR) detector without sample pre-handling was developed for DOX monitoring. First, the two-dimensional metal-organic framework was modified on the Au film to enhance SPR, and then, the supramolecular probes with tunable cavity structure were self-assembled at the sensing interface for direct detection of DOX through specific host-guest interactions with a low detection limit of 60.24 pM. The precise monitoring of DOX in serum proved the possibility of clinical application with recoveries in the range 102.86-109.47%. The mechanisms of host-guest interactions between supramolecular and small-molecule drugs were explored in depth through first-principles calculations combined with SPR experiments. The study paves the way for designing facile and sensitive detectors and provides theoretical support and a new methodology for the specific detection of small molecules through calixarene cavity modulation.

Phytoconstituents from Piliostigma foveolatum (Dalzell) Thoth. leaves induce antiproliferative effect, apoptosis, and cell cycle arrest in Hop-62 cells

The study evaluated the therapeutic potential of ethanolic leaf extract of Piliostigma foveolatum (Dalzell) Thoth. (EEBF), its toluene, ethylacetate, methanol soluble fractions (viz. TFBF, EFBF, MFBF), and isolated phytoconstituents against lung cancer. Four compounds were isolated from MFBF by column chromatography and preparative HPLC. Structures were elucidated by IR, 13C-NMR, 1H-NMR, mass spectroscopy and identified as Quercetin, Kaempferol, Isorhamnetin, and ß-glucogallin. EEBF and its biofractions exhibited remarkable antiproliferative activity with GI50<85µg/mL, while isolated Quercetin, Kaempferol, Isorhamnetin, and ß-Glucogallin displayed GI50 values of 56.15 ± 1.16 μ M, 68.41 ± 3.98 μ M, 55.08 ± 0.57 μ M and 58.99 ± 12.39 μ M respectively. MFBF demonstrated significant apoptotic activity with 42.24 ± 0.57% cells in early and 4.61 ± 0.88% cells in late apoptosis comparable to standard Doxorubicin. Kaempferol exhibited 23.03 ± 0.37% cells in early and 2.11 ± 0.55% cells in late apoptosis, arresting Hop-62 cells in S-phase. In silico molecular docking, revealed that isolated constituents effectively bound to the same binding site of caspase-3 as Doxorubicin, highlighting their apoptotic mode of action.

Ultrasensitive two-photon probes for rapid detection of β-galactosidase during fruit softening and cellular senescence

Senescence is happening in every corner of the living organisms. β-galactosidase (β-gal) is one of the most important biomarkers during senescence in both plant and mammalian cells. Most β-gal fluorescent probes were focused on bio-imaging, only a few probes were developed for the detection of β-gal in fruit, and the probes that could detect β-gal in both fruits and living cells were even less. Here, two β-gal probes (TNap-βGal and TBNap-βGal) were synthesized, which can not only image the increase of β-gal during both fruits softening and cellular senescence, but also prove that bananas are not suitable for storage in refrigerator and the subsequent accumulation of β-gal still in lysosome of mammalian cells. In addition, TNap-βGal was successfully applied to two-photon imaging of endogenous β-gal in both hDPMSCs and tissues of human dental pulp for the first time.

Cellular senescence triggers intracellular acidification and lysosomal pH alkalinized via ATP6AP2 attenuation in breast cancer cells

Several chemotherapeutic drugs induce senescence in cancer cells; however, the mechanisms underlying intracellular pH dysregulation in senescent cells remain unclear. Adenosine triphosphatase H+ transporting accessory protein 2 (ATP6AP2) plays a critical role in maintaining pH homeostasis in cellular compartments. Herein, we report the regulatory role of ATP6AP2 in senescent breast cancer cells treated with doxorubicin (Doxo) and abemaciclib (Abe). A decline in ATP6AP2 triggers aberrant pH levels that impair lysosomal function and cause immune profile changes in senescent breast cancer cells. Doxo and Abe elicited a stable senescent phenotype and altered the expression of senescence-related genes. Additionally, senescent cells show altered inflammatory and immune transcriptional profiles due to reprogramming of the senescence-associated secretory phenotype. These findings elucidate ATP6AP2-mediated cellular pH regulation and suggest a potential link in immune profile alteration during therapy-induced senescence in breast cancer cells, providing insights into the mechanisms involved in the senescence response to anticancer therapy.

Intracellular FGF1 protects cells from apoptosis through direct interaction with p53

Fibroblast growth factor 1 (FGF1) acts by activating specific tyrosine kinase receptors on the cell surface. In addition to this classical mode of action, FGF1 also exhibits intracellular activity. Recently, we found that FGF1 translocated into the cell interior exhibits anti-apoptotic activity independent of receptor activation and downstream signaling. Here, we show that expression of FGF1 increases the survival of cells treated with various apoptosis inducers, but only when wild-type p53 is present. The p53-negative cells were not protected by either ectopically expressed or translocated FGF1. We also confirmed the requirement of p53 for the anti-apoptotic intracellular activity of FGF1 by silencing p53, resulting in loss of the protective effect of FGF1. In contrast, in p53-negative cells, intracellular FGF1 regained its anti-apoptotic properties after transfection with wild-type p53. We also found that FGF1 directly interacts with p53 in cells and that the binding region is located in the DBD domain of p53. We therefore postulate that intracellular FGF1 protects cells from apoptosis by directly interacting with p53.

Doxorubicin and other anthracyclines in cancers: Activity, chemoresistance and its overcoming

Anthracyclines have been important and effective treatments against a number of cancers since their discovery. However, their use in therapy has been complicated by severe side effects and toxicity that occur during or after treatment, including cardiotoxicity. The mode of action of anthracyclines is complex, with several mechanisms proposed. It is possible that their high toxicity is due to the large set of processes involved in anthracycline action. The development of resistance is a major barrier to successful treatment when using anthracyclines. This resistance is based on a series of mechanisms that have been studied and addressed in recent years. This work provides an overview of the anthracyclines used in cancer therapy. It discusses their mechanisms of activity, toxicity, and chemoresistance, as well as the approaches used to improve their activity, decrease their toxicity, and overcome resistance.

A hybrid breast cancer/mesenchymal stem cell population enhances chemoresistance and metastasis

Patients with triple-negative breast cancer remain at risk for metastatic disease despite treatment. The acquisition of chemoresistance is a major cause of tumor relapse and death, but the mechanisms are far from understood. We have demonstrated that breast cancer cells (BCCs) can engulf mesenchymal stem/stromal cells (MSCs), leading to enhanced dissemination. Here, we show that clinical samples of primary invasive carcinoma and chemoresistant breast cancer metastasis contain a unique hybrid cancer cell population coexpressing pancytokeratin and the MSC marker fibroblast activation protein-α. We show that hybrid cells form in primary tumors and that they promote breast cancer metastasis and chemoresistance. Using single-cell microfluidics and in vivo models, we found that there are polyploid senescent cells within the hybrid cell population that contribute to metastatic dissemination. Our data reveal that Wnt Family Member 5A (WNT5A) plays a crucial role in supporting the chemoresistance properties of hybrid cells. Furthermore, we identified that WNT5A mediates hybrid cell formation through a phagocytosis-like mechanism that requires BCC-derived IL-6 and MSC-derived C-C Motif Chemokine Ligand 2. These findings reveal hybrid cell formation as a mechanism of chemoresistance and suggest that interrupting this mechanism may be a strategy in overcoming breast cancer drug resistance.

Racial Disparity in Anthracycline-induced Cardiotoxicity in Breast Cancer Patients

Breast cancer has become the most common cancer in the US and worldwide. While advances in early detection and treatment have resulted in a 40% reduction in breast cancer mortality, this reduction has not been achieved uniformly among racial groups. A large percentage of non-metastatic breast cancer mortality is related to the cardiovascular effects of breast cancer therapies. These effects appear to be more prevalent among patients from historically marginalized racial/ethnic backgrounds, such as African American and Hispanic individuals. Anthracyclines, particularly doxorubicin and daunorubicin, are the first-line treatments for breast cancer patients. However, their use is limited by their dose-dependent and cumulative cardiotoxicity, manifested by cardiomyopathy, ischemic heart disease, arrhythmias, hypertension, thromboembolic disorders, and heart failure. Cardiotoxicity risk factors, such as genetic predisposition and preexisting obesity, diabetes, hypertension, and heart diseases, are more prevalent in racial/ethnic minorities and undoubtedly contribute to the risk. Yet, beyond these risk factors, racial/ethnic minorities also face unique challenges that contribute to disparities in the emerging field of cardio-oncology, including socioeconomic factors, food insecurity, and the inability to access healthcare providers, among others. The current review will address genetic, clinical, and social determinants that potentially contribute to this disparity.

Effect of an NGR Peptide on the Efficacy of the Doxorubicin Phospholipid Delivery System

This study is a continuation of an investigation into the effect of a targeted component, a peptide with an NGR, on the properties of the previously developed doxorubicin phospholipid delivery system. The NGR peptide has an affinity for aminopeptidase N (known as the CD13 marker on the membrane surface of tumor cells) and has been extensively used to target drug delivery systems. This article presents the results of a study investigating the physical properties of the phospholipid composition with and without the peptide chain: particle size, zeta potential, stability in fluids, and dependence of doxorubicin release from nanoparticles at different pH levels (5.0, 6.5, 7.4). The cytotoxic effect of the compositions has also been shown to depend on the dose of the drug used for incubation, the presence of the targeted component in the composition, and the time of incubation time of the substances. There was a significant difference in the cytotoxic effect on HT-1080 (CD13-positive) and MCF-7 (CD13-negative) cells. Cell death pathway analysis has shown that death occurred mainly by apoptosis. We also present data on the effect of doxorubicin embedded in phospholipid nanoparticles with the targeted peptide on DNA assessed by differential pulse voltammetry, the mechanism of action being electrostatic interactions. The interactions of native dsDNA with doxorubicin encapsulated in phospholipid nanoparticles with the targeted peptide were studied electrochemically by differential pulse voltammetry. Here, we have highlighted that the targeted peptide in the doxorubicin composition moved specific interaction of the drug with dsDNA from intercalative mode to electrostatic interactions.

PEG-liposomal doxorubicin as a potential agent for canine metastatic osteosarcoma - in vitro and ex ovo studies

Introduction

Appendicular osteosarcoma (OSA) is a highly aggressive and metastatic primary bone tumour in dogs. Standard therapy is amputation and adjuvant chemotherapy (e.g. with doxorubicin). Liposomal drug delivery may augment therapeutic efficacy and reduce negative side effects. Polyethylene glycol (PEG)-liposomal doxorubicin treats human metastatic cancers effectively. The study aimed was to evaluate PEG-liposomal doxorubicin's inhibitory effect on canine metastatic proliferation and migration in vitro. It also aimed to appraise the drug's extravasation inhibition in vivo using the human medicine-proven chick embryo chorioallantoic membrane ex ovo model.

Material and Methods

The canine D-17 OSA cell line was cultured and inoculated with decreasing concentrations of PEG-liposomal doxorubicin and conventional doxorubicin in a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) test of cell viability, proliferation and cytotoxicity. Flow cytometry with Annexin V and Draq 7 staining confirmed the MTT test results, indicating dead, early and late apoptotic, and live cells. The inhibitory effect of the two preparations on cancer cell migration was investigated with a wound-healing assay. Culture plates seeded with cells were prepared. The cell monolayer was scratched and images of cells migrating to the scratch were captured at 0 h, 12 h and 24 h. Also, embryos were removed from three-day-incubated fertilised chicken eggs. On the 12th day, labelled D-17 cells were injected into each embryo. Embryos in one group received 100 μL of phosphate-buffered saline as controls, those in another group 30 μg/mL of PEG-liposomal doxorubicin, and those in the last group 6 μg/mL of conventional doxorubicin. The effectiveness of the intravascular administration of the D-17 cells was confirmed under a microscope.

Results

PEG-liposomal doxorubicin inhibited the migration of canine OSA cells more effectively than conventional doxorubicin (P ≤ 0.05). The ex ovo model showed that both drugs had similar impacts on canine metastatic OSA.

Conclusion

The liposomal form of the drug may be considered a potentially effective compound in canine metastatic OSA; nevertheless, further in vivo studies are essential to confirm this hypothesis.

Peptide-Functionalized and Drug-Loaded Tomato Bushy Stunt Virus Nanoparticles Counteract Tumor Growth in a Mouse Model of Shh-Dependent Medulloblastoma

Sonic hedgehog medulloblastoma (SHH-MB) accounts for 25-30% of all MBs, and conventional therapy results in severe long-term side effects. New targeted therapeutic approaches are urgently needed, drawing also on the fields of nanoparticles (NPs). Among these, plant viruses are very promising, and we previously demonstrated that tomato bushy stunt virus (TBSV), functionalized on the surface with CooP peptide, specifically targets MB cells. Here, we tested the hypothesis that TBSV-CooP can specifically deliver a conventional chemotherapeutic drug (i.e., doxorubicin, DOX) to MB in vivo. To this aim, a preclinical study was designed to verify, by histological and molecular methods, if multiple doses of DOX-TBSV-CooP were able to inhibit tumor progression of MB pre-neoplastic lesions, and if a single dose was able to modulate pro-apoptotic/anti-proliferative molecular signaling in full-blown MBs. Our results demonstrate that when DOX is encapsulated in TBSV-CooP, its effects on cell proliferation and cell death are similar to those obtained with a five-fold higher dose of non-encapsulated DOX, both in early and late MB stages. In conclusion, these results confirm that CooP-functionalized TBSV NPs are efficient carriers for the targeted delivery of therapeutics to brain tumors.

Prolactin-induced protein (PIP) increases the sensitivity of breast cancer cells to drug-induced apoptosis

We have previously shown that high expression of prolactin-induced protein (PIP) correlates with the response of breast cancer (BC) patients to standard adjuvant chemotherapy (doxorubicin and cyclophosphamide), which suggests that the absence of this glycoprotein is associated with resistance of tumor cells to chemotherapy. Therefore, in the present study, we analyzed the impact of PIP expression on resistance of BC cells to anti-cancer drugs and its biological role in BC progression. Expression of PIP and apoptotic genes in BC cell lines was analyzed using real-time PCR and Western blotting. PIP was detected in BC tissue specimens using immunohistochemistry. The tumorigenicity of cancer cells was analyzed by the in vivo tumor growth assay. Apoptotic cells were detected based on caspase-3 activation, Annexin V binding and TUNEL assay. The interaction of PIP with BC cells was analyzed using flow cytometry. Using two cellular models of BC (i.e. T47D cells with the knockdown of the PIP gene and MDA-MB-231 cells overexpressing PIP), we found that high expression of PIP resulted in (1) increased sensitivity of BC cells to apoptosis induced by doxorubicin (DOX), 4-hydroperoxycyclophosphamide (4-HC), and paclitaxel (PAX), and (2) improved efficacy of anti-cancer therapy with DOX in the xenograft mice model. Accordingly, a clinical study revealed that BC patients with higher PIP expression were characterized by longer 5-year overall survival and disease-free survival. Subsequent studies showed that PIP up-regulated the expression of the following pro-apoptotic genes: CRADD, DAPK1, FASLG, CD40 and BNIP2. This pro-apoptotic activity is mediated by secreted PIP and most probably involves the specific surface receptor. This study demonstrates that a high expression level of PIP sensitizes BC cells to anti-cancer drugs. Increased sensitivity to chemotherapy is the result of pro-apoptotic activity of PIP, which is evidenced by up-regulation of specific pro-apoptotic genes. As high expression of PIP significantly correlated with a better response of patients to anti-cancer drugs, this glycoprotein can be a marker for the prognostic evaluation of adjuvant chemotherapy.

Induction of filamin-C and its involvement in the regulation of cellular senescence and apoptosis in Huh-7 hepatoma cells during arsenic trioxide exposure

Arsenic trioxide (ATO) is one of the most toxic inorganic arsenic compounds. In this study, we examined the effects of long-term (7 days) exposure to low dose (5 μM) ATO on a human hepatocellular carcinoma cell line, Huh-7. Along with apoptosis accompanied by secondary necrosis though GSDME cleavage, we observed enlarged and flattened cells adhering to the culture dish and surviving even after exposure to ATO. An increase in cyclin-dependent kinase inhibitor p21 levels as well as positive staining for senescence-associated β-galactosidase activity were observed in ATO-treated cells, indicating cellular senescence. Screening for both ATO-inducible proteins by MALDI-TOF-MS analysis and ATO-inducible genes by DNA microarray analysis showed a marked increase in filamin-C (FLNC), an actin cross-linking protein. Interestingly, the increase in FLNC was observed in both dead and surviving cells, suggesting that the upregulation of FLNC by ATO occurs in both apoptotic and senescent cells. Small interference RNA-mediated knock down of FLNC resulted in not only a reduction of senescence-associated enlarged morphology of the cells, but also an exacerbation of cell death. Taken together, these results suggest a regulatory role of FLNC in the execution of senescence as well as apoptosis during ATO exposure.

Silibinin induces immunogenic cell death in cancer cells and enhances the induced immunogenicity by chemotherapy

Introduction: Silibinin is a natural flavonoid compound known to induce apoptosis in cancer cells. Despite silibinin's safety and efficacy as an anticancer drug, its effects on inducing immunogenic cell death (ICD) are largely unknown. Herein, we have evaluated the stimulating effects of silibinin on ICD in cancer cells treated with silibinin alone or in combination with chemotherapy. Methods: The anticancer effect of silibinin, alone or in combination with doxorubicin or oxaliplatin (OXP), was assessed using the MTT assay. Compusyn software was used to analyze the combination therapy data. Western blotting was conducted to examine the level of STAT3 activity. Flow cytometry was used to analyze calreticulin (CRT) and apoptosis. The heat shock protein (HSP70), high mobility group box protein1 (HMGB1), and IL-12 levels were assessed by ELISA. Results: Compared to the negative control groups, silibinin induced ICD in CT26 and B16F10 cells and significantly enhanced the induction of this type of cell death by doxorubicin, and these changes were allied with substantial increases in the level of damage-associated molecular patterns (DAMPs) including CRT, HSP70, and HMGB1. Furthermore, conditioned media from cancer cells exposed to silibinin and doxorubicin was found to stimulate IL-12 secretion in dendritic cells (DCs), suggesting the link of this treatment with the induction of Th1 response. Silibinin did not augment the ICD response induced by OXP. Conclusion: Our findings showed that silibinin can induce ICD and it potentiates the induction of this type of cell death induced by chemotherapy in cancer cells.

Inhibition of Protein Disulfide Isomerase (PDIA1) Leads to Proteasome-Mediated Degradation of Ubiquitin-like PHD and RING Finger Domain-Containing Protein 1 (UHRF1) and Increased Sensitivity of Glioblastoma Cells to Topoisomerase II Inhibitors

Glioblastoma (GBM) is the most aggressive brain tumor, and the prognosis remains poor with current available treatments. PDIA1 is considered a promising therapeutic target in GBM. In this study, we demonstrate that targeting PDIA1 results in increased GBM cell death by topoisomerase II (Top-II) inhibitors resulting in proteasome-mediated degradation of the oncogenic protein UHRF1. Combination of the PDIA1 inhibitor, bepristat-2a, produces strong synergy with doxorubicin, etoposide, and mitoxantrone in GBM and other cancer cell lines. Our bioinformatics analysis of multiple datasets revealed downregulation of UHRF1, upon PDIA1 inhibition. In addition, PDIA1 inhibition results in proteasome-mediated degradation of UHRF1 protein. Interestingly, treatment of GBM cells with bepristat-2a results in increased apoptosis and resistance to ferroptosis. Our findings emphasize the importance of PDIA1 as a therapeutic target in GBM and present a promising new therapeutic approach using Top-II inhibitors for GBM treatment.

Amplification of anticancer efficacy by co-delivery of doxorubicin and lonidamine with extracellular vesicles

Chemotherapy is commonly used for the treatment of lung cancer, but strong side effects and low treatment efficacy limit its clinical application. Here, extracellular vesicles (EVs) as natural drug delivery carriers were used to load conventional anticancer drug doxorubicin (DOX) and a chemosensitizer lonidamine (LND). Two types of EVs with different sizes (16k EVs and 120k EVs) were prepared using different centrifugation forces. We found that co-delivery of DOX and LND with both EVs enhanced the cytotoxicity and reduced the dose of the anticancer drug significantly in vitro. Effective delivery of anti-cancer drugs to cancer cells was achieved by direct fusion of EVs with the plasma membrane of cancer cells. On the other hand, DOX and LND inhibited cancer cell proliferation by increasing DNA damage, suppressing ATP production, and accelerating ROS generation synergistically. DOX and LND loaded EVs were also applied to the mouse lung cancer model and exhibited significant anticancer activity. In vivo study showed that smaller EVs exhibited higher anticancer efficiency. In conclusion, the co-delivery of the anticancer drug and the chemosensitizer with EVs may have potential clinical applications for cancer therapy.

Targeting of non-apoptotic cancer cell death mechanisms by quercetin: Implications in cancer therapy

The ultimate goal of cancer treatment is to kill cancer cells, based on the use of various therapeutic agents, such as chemotherapy, radiotherapy, or targeted therapy drugs. Most drugs exert their therapeutic effects on cancer by targeting apoptosis. However, alterations in apoptosis-related molecules and thus assisting cells to evade death, eventually lead to tumor cell resistance to therapeutic drugs. The increased incidence of non-apoptotic cell death modes such as induced autophagy, mitotic catastrophe, senescence, and necrosis is beneficial to overcoming multidrug resistance mediated by apoptosis resistance in tumor cells. Therefore, investigating the function and mechanism of drug-induced non-apoptotic cell death modes has positive implications for the development of new anti-cancer drugs and therapeutic strategies. Phytochemicals show strong potential as an alternative or complementary medicine for alleviating various types of cancer. Quercetin is a flavonoid compound widely found in the daily diet that demonstrates a significant role in inhibiting numerous human cancers. In addition to direct pro-tumor cell apoptosis, both in vivo and in vitro experiments have shown that quercetin exerts anti-tumor properties by triggering diverse non-apoptotic cell death modes. This review summarized the current status of research on the molecular mechanisms and targets through which quercetin-mediated non-apoptotic mode of cancer cell death, including autophagic cell death, senescence, mitotic catastrophe, ferroptosis, necroptosis, etc.

Metabolomic Signatures in Doxorubicin-Induced Metabolites Characterization, Metabolic Inhibition, and Signaling Pathway Mechanisms in Colon Cancer HCT116 Cells

Doxorubicin (DOX) is a chemotherapeutic agent is used for various cancer cells. To characterize the chemical structural components and metabolic inhibition, we applied a DOX to HCT116 colon cancer cells using an independent metabolites profiling approach. Chemical metabolomics has been involved in the new drug delivery systems. Metabolomics profiling of DOX-applied HCT116 colon cancer cellular metabolisms is rare. We used 1H nuclear magnetic resonance (NMR) spectroscopy in this study to clarify how DOX exposure affected HCT116 colon cancer cells. Metabolomics profiling in HCT116 cells detects 50 metabolites. Tracking metabolites can reveal pathway activities. HCT116 colon cancer cells were evenly treated with different concentrations of DOX for 24 h. The endogenous metabolites were identified by comparison with healthy cells. We found that acetate, glucose, glutamate, glutamine, sn-glycero-3-phosphocholine, valine, methionine, and isoleucine were increased. Metabolic expression of alanine, choline, fumarate, taurine, o-phosphocholine, inosine, lysine, and phenylalanine was decreased in HCT116 cancer cells. The metabolic phenotypic expression is markedly altered during a high dose of DOX. It is the first time that there is a metabolite pool and phenotypic expression in colon cancer cells. Targeting the DOX-metabolite axis may be a novel strategy for improving the curative effect of DOX-based therapy for colon cancer cells. These methods facilitate the routine metabolomic analysis of cancer cells.

Membrane-Wrapped Nanoparticles for Enhanced Chemotherapy of Acute Myeloid Leukemia

This work reports the development of a biomimetic membrane-wrapped nanoparticle (MWNP) platform for targeted chemotherapy of acute myeloid leukemia (AML). Doxorubicin (DOX), a chemotherapeutic used to treat leukemias, lymphomas, and other cancers, was encapsulated in polymeric NPs that were coated with cytoplasmic membranes derived from human AML cells. The release rate of DOX from the MWNPs was characterized under both storage and physiological conditions, with faster release observed at pH 5.5 than pH 7.4. The system was then introduced to AML cell cultures to test the functionality of the released DOX cargo as compared to DOX delivered freely or via NPs coated with poly(ethylene glycol) (PEG). The MWNPs delivered DOX in an efficient and targeted manner, inducing up to 80% apoptosis in treated cells at a dose of 5 μM, compared to 15% for free DOX and 17% for DOX-loaded PEG-coated NPs at the same drug concentration. The mechanism of cell death was confirmed as DNA double-strand breaks through a γH2A.X assay, indicating that the released DOX retained its expected mechanism of action. These findings designate MWNPs as a robust drug delivery system with great potential for future development in treatments of AML and other blood cancers.

Evaluation of the cytotoxic, anticancer, and genotoxic activities of Acacia nilotica flowers and their effects on N-methyl-N-nitrosourea-induced genotoxicity in mice

Purpose

In this study, two main research objectives were examined: (1) the cytotoxic and anticancer activities of the aqueous methanol extract from Acacia nilotica flowers on three human cancer cells, namely lung A549, breast MCF-7, and leukemia THP-1 cells, and (2) the genotoxic effects of A. nilotica extract and its influence on DNA damage induced by N-methyl-N-nitrosourea (MNU) in mice.

Methods

Mice were orally treated with A. nilotica extract (200, 500, and 800 mg/kg for 4 days) with or without MNU (80 mg/kg intraperitoneally for 24 h).

Results

In vitro experiments showed that A549 cells were the most sensitive to A. nilotica extract among the tested cell lines. A. nilotica extract inhibited A549 cell proliferation by blocking the cell cycle at the G₂/M phase and accumulating apoptotic cells in the sub-G₀/G₁ phase in A549 cells. In vivo experiments showed that MNU induced positive and negative genotoxicity in bone marrow cells and spermatocytes, respectively. Negative genotoxicity was observed in A. nilotica extract-treated groups only. However, A. nilotica extract (800 mg/kg) remarkably increased comet tail formation in bone marrow cells. Unexpectedly, the absence of antigenotoxicity was observed in three cotreated groups with A. nilotica extract and MNU compared with the MNU-treated group. Astonishingly, cotreatment with MNU and A. nilotica extract at a dose above 200 mg/kg remarkably increased micronucleus and comet tail formation in bone marrow cells compared with the MNU-treated group.

Conclusions

A. nilotica extract possessed anticancer activity with relative genotoxic effects at high doses.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11033-022-07662-0.

The identification of the anthracycline aclarubicin as an effective cytotoxic agent for pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal types of cancer, mainly due to its delayed diagnosis and lack of effective therapeutic options. Therefore, it is imperative to find novel treatment options for PDAC. Here, we tested a series of conventional chemotherapeutics together with anthracycline compounds as single agents or in combination, determining their effectivity against established commercial and patient-derived, low-passage PDAC cell lines. Proliferation and colony formation assays were performed to determine the anticancer activity of anthracyclines; aclarubicin and doxorubicin, on commercial and patient-derived, low-passage PDAC cell lines. In addition, the effect of standard-of-care drugs gemcitabine and individual components of FOLFIRINOX were also investigated. To evaluate which mechanisms of cell death were involved in drug response, cleavage of poly(ADP-ribose)polymerase was evaluated by western blot. Aclarubicin showed superior antitumor activity compared to other anthracyclines and standard of care drugs (gemcitabine and individual components of FOLFIRINOX) in a patient-derived, low-passage PDAC cell line and in commercial cell lines. Importantly, the combination of gemcitabine and aclarubicin showed a synergistic effect at a dose range where the single agents by themselves were ineffective. In parallel, evaluation of the antitumor activity of aclarubicin demonstrated an apoptotic effect in all PDAC cell lines. Aclarubicin is cytotoxic for commercial and patient-derived low-passage PDAC cell lines, at doses lower than peak serum concentrations for patient treatment. Our findings support a (re)consideration of aclarubicin as a backbone of new combination regimens for pancreatic cancer patients.

A High-Throughput Screening Platform Identifies Novel Combination Treatments for Malignant Peripheral Nerve Sheath Tumors

Malignant peripheral nerve sheath tumors (MPNST) are soft-tissue sarcomas that are the leading cause of mortality in patients with Neurofibromatosis type 1 (NF1). Single chemotherapeutic agents have shown response rates ranging from 18% to 44% in clinical trials, so there is still a high medical need to identify chemotherapeutic combination treatments that improve clinical prognosis and outcome. We screened a collection of compounds from the NCATS Mechanism Interrogation PlatE (MIPE) library in three MPNST cell lines, using cell viability and apoptosis assays. We then tested whether compounds that were active as single agents were synergistic when screened as pairwise combinations. Synergistic combinations in vitro were further evaluated in patient-derived orthotopic xenograft/orthoxenograft (PDOX) athymic models engrafted with primary MPNST matching with their paired primary-derived cell line where synergism was observed. The high-throughput screening identified 21 synergistic combinations, from which four exhibited potent synergies in a broad panel of MPNST cell lines. One of the combinations, MK-1775 with Doxorubicin, significantly reduced tumor growth in a sporadic PDOX model (MPNST-SP-01; sevenfold) and in an NF1-PDOX model (MPNST-NF1-09; fourfold) and presented greater effects in TP53 mutated MPNST cell lines. The other three combinations, all involving Panobinostat (combined with NVP-BGT226, Torin 2, or Carfilzomib), did not reduce the tumor volume in vivo at noncytotoxic doses. Our results support the utility of our screening platform of in vitro and in vivo models to explore new therapeutic approaches for MPNSTs and identified that combination MK-1775 with Doxorubicin could be a good pharmacologic option for the treatment of these tumors.

Targeting tumor cell senescence and polyploidy as potential therapeutic strategies

Senescence is a unique state of growth arrest that develops in response to a plethora of cellular stresses, including replicative exhaustion, oxidative injury, and genotoxic insults. Senescence has been implicated in the pathogenesis of multiple aging-related pathologies, including cancer. In cancer, senescence plays a dual role, initially acting as a barrier against tumor progression by enforcing a durable growth arrest in premalignant cells, but potentially promoting malignant transformation in neighboring cells through the secretion of pro-tumorigenic drivers. Moreover, senescence is induced in tumor cells upon exposure to a wide variety of conventional and targeted anticancer drugs (termed Therapy-Induced Senescence-TIS), representing a critical contributing factor to therapeutic outcomes. As with replicative or oxidative senescence, TIS manifests as a complex phenotype of macromolecular damage, energetic dysregulation, and altered gene expression. Senescent cells are also frequently polyploid. In vitro studies have suggested that polyploidy may confer upon senescent tumor cells the ability to escape from growth arrest, thereby providing an additional avenue whereby tumor cells escape the lethality of anticancer treatment. Polyploidy in tumor cells is also associated with persistent energy production, chromatin remodeling, self-renewal, stemness and drug resistance - features that are also associated with escape from senescence and conversion to a more malignant phenotype. However, senescent cells are highly heterogenous and can present with variable phenotypes, where polyploidy is one component of a complex reversion process. Lastly, emerging efforts to pharmacologically target polyploid tumor cells might pave the way towards the identification of novel targets for the elimination of senescent tumor cells by the incorporation of senolytic agents into cancer therapeutic strategies.

The Beneficial Role of Physical Exercise on Anthracyclines Induced Cardiotoxicity in Breast Cancer Patients

The increase in breast cancer (BC) survival has determined a growing survivor population that seems to develop several comorbidities and, specifically, treatment-induced cardiovascular disease (CVD), especially those patients treated with anthracyclines. Indeed, it is known that these compounds act through the induction of supraphysiological production of reactive oxygen species (ROS), which appear to be central mediators of numerous direct and indirect cardiac adverse consequences. Evidence suggests that physical exercise (PE) practised before, during or after BC treatments could represent a viable non-pharmacological strategy as it increases heart tolerance against many cardiotoxic agents, and therefore improves several functional, subclinical, and clinical parameters. At molecular level, the cardioprotective effects are mainly associated with an exercise-induced increase of stress response proteins (HSP60 and HSP70) and antioxidant (SOD activity, GSH), as well as a decrease in lipid peroxidation, and pro-apoptotic proteins such as Bax, Bax-to-Bcl-2 ratio. Moreover, this protection can potentially be explained by a preservation of myosin heavy chain (MHC) isoform distribution. Despite this knowledge, it is not clear which type of exercise should be suggested in BC patient undergoing anthracycline treatment. This highlights the lack of special guidelines on how affected patients should be managed more efficiently. This review offers a general framework for the role of anthracyclines in the physio-pathological mechanisms of cardiotoxicity and the potential protective role of PE. Finally, potential exercise-based strategies are discussed on the basis of scientific findings.

Necroptosis as a Novel Facet of Mitotic Catastrophe

Mitotic catastrophe is a defensive mechanism that promotes elimination of cells with aberrant mitosis by triggering the cell-death pathways and/or cellular senescence. Nowadays, it is known that apoptosis, autophagic cell death, and necrosis could be consequences of mitotic catastrophe. Here, we demonstrate the ability of a DNA-damaging agent, doxorubicin, at 600 nM concentration to stimulate mitotic catastrophe. We observe that the inhibition of caspase activity leads to accumulation of cells with mitotic catastrophe hallmarks in which RIP1-dependent necroptotic cell death is triggered. The suppression of autophagy by a chemical inhibitor or ATG13 knockout upregulates RIP1 phosphorylation and promotes necroptotic cell death. Thus, in certain conditions mitotic catastrophe, in addition to apoptosis and autophagy, can precede necroptosis.

Quantification of long-term doxorubicin response dynamics in breast cancer cell lines to direct treatment schedules

While acquired chemoresistance is recognized as a key challenge to treating many types of cancer, the dynamics with which drug sensitivity changes after exposure are poorly characterized. Most chemotherapeutic regimens call for repeated dosing at regular intervals, and if drug sensitivity changes on a similar time scale then the treatment interval could be optimized to improve treatment performance. Theoretical work suggests that such optimal schedules exist, but experimental confirmation has been obstructed by the difficulty of deconvolving the simultaneous processes of death, adaptation, and regrowth taking place in cancer cell populations. Here we present a method of optimizing drug schedules in vitro through iterative application of experimentally calibrated models, and demonstrate its ability to characterize dynamic changes in sensitivity to the chemotherapeutic doxorubicin in three breast cancer cell lines subjected to treatment schedules varying in concentration, interval between pulse treatments, and number of sequential pulse treatments. Cell populations are monitored longitudinally through automated imaging for 600–800 hours, and this data is used to calibrate a family of cancer growth models, each consisting of a system of ordinary differential equations, derived from the bi-exponential model which characterizes resistant and sensitive subpopulations. We identify a model incorporating both a period of growth arrest in surviving cells and a delay in the death of chemosensitive cells which outperforms the original bi-exponential growth model in Akaike Information Criterion based model selection, and use the calibrated model to quantify the performance of each drug schedule. We find that the inter-treatment interval is a key variable in determining the performance of sequential dosing schedules and identify an optimal retreatment time for each cell line which extends regrowth time by 40%-239%, demonstrating that the time scale of changes in chemosensitivity following doxorubicin exposure allows optimization of drug scheduling by varying this inter-treatment interval.

Acquired chemoresistance is a common cause of treatment failure in cancer. The scheduling of a multi-dose course of chemotherapeutic treatment may influence the dynamics of acquired chemoresistance, and drug schedule optimization may increase the duration of effectiveness of a particular chemotherapeutic agent for a particular patient. Here we present a method for experimentally optimizing an in vitro drug schedule through iterative rounds of experimentation and computational analysis, and demonstrate the method’s ability to improve the performance of doxorubicin treatment in three breast carcinoma cell lines. Specifically, we find that the interval between drug exposures can be optimized while holding drug concentration and number of treatments constant, suggesting that this may be a key variable to explore in future drug schedule optimization efforts. We further use this method’s model calibration and selection process to extract information about the underlying biology of the doxorubicin response, and find that the incorporation of delays on both cell death and regrowth are necessary for accurate parameterization of cell growth data.

IMB5476, a novel microtubule inhibitor, induces mitotic catastrophe and overcomes multidrug resistance in tumors

IMB5046 is a nitrobenzoate microtubule inhibitor we reported previously. During screening of its structural analogues, we identified a novel compound IMB5476 with increased aqueous solubility. Here, its antitumor activity and the underlying mechanism were investigated. IMB5476 disrupted microtubule networks in cells and arrested cell cycle at G2/M phase. It inhibited purified tubulin polymerization in vitro. Competition assay indicated that it bound to tubulin at the colchicine pocket. Further experiments proved that it induced cell death by mitotic catastrophe and apoptosis. Notably, it was a poor substrate of P-glycoprotein and exhibited potent cytotoxicity against drug-resistant tumor cells. In addition, IMB5476 could inhibit angiogenesis in vitro. IMB5476 also inhibited the growth of drug-resistant KB_V200 xenografts in mice. Conclusively, our data reveal a novel nitrobenzoate microtubule inhibitor with improved aqueous solubility and can overcome multidrug resistance.

Survivin suppression heightens BZML-induced mitotic catastrophe to overcome multidrug resistance by removing therapy-induced senescent A549/Taxol cells

Mitotic catastrophe (MC) is a newly identified type of anticancer mechanism for multidrug resistance (MDR) prevention. However, the long cellular death process resulting from MC is not beneficial for anticancer treatment. BZML is a novel colchicine-binding site inhibitor which can overcome MDR by inducing MC; however, BZML-induced MC cells underwent a long cellular death process. Thus, to improve anticancer therapies based on drug-induced MC, BZML-induced MC was served as a model to further study the underlying molecular mechanisms in the process of MC. Here, BZML could induce p53-dependent senescence in A549/Taxol cells, a MDR cell line. This senescence was a secondary effect of MC in overcoming MDR. During MC, BZML-induced destruction of protein-degradation system contributed not only to an increase of p53 protein but also to the accumulation of survivin in nucleus of A549/Taxol cells. Importantly, the nuclear accumulation of survivin was not the inducer but the result of BZML-induced MC, and it promoted the survival of senescent cells. Moreover, it provided additional vulnerability and critical opportunities for sequentially applied therapies. Further, targeting survivin with YM155 accelerated the death of MC cells by timely eliminating therapy-induced senescent cells and strengthening the efficiency of BZML in overcoming MDR in A549/Taxol cells. Collectively, nuclear accumulation of survivin delayed cellular death during MC by promoting the survival of BZML-induced senescent A549/Taxol cells. Moreover, "one-two punch" approach to cancer treatment based on combination therapy with YM155 for survivin suppression might be a new strategy for potentiating MC to overcome MDR.

Targeted liposomal doxorubicin/ceramides combinations: the importance to assess the nature of drug interaction beyond bulk tumor cells

One of the major assets of anticancer nanomedicine is the ability to co-deliver drug combinations, as it enables targeting of different cellular populations and/or signaling pathways implicated in tumorigenesis and thus tackling tumor heterogeneity. Moreover, drug resistance can be circumvented, for example, upon co-encapsulation and delivery of doxorubicin and sphingolipids, as ceramides. Herein, the impact of short (C6) and long (C18) alkyl chain length ceramides on the nature of drug interaction, within the scope of combination with doxorubicin, was performed in bulk triple-negative breast cancer (TNBC) cells, as well as on the density of putative cancer stem cells and phenotype, including live single-cell tracking. C6- or C18-ceramide enabled a synergistic drug interaction in all conditions and (bulk) cell lines tested. However, differentiation among these two ceramides was reflected on the migratory potential of cancer cells, particularly significant against the highly motile MDA-MB-231 cells. This effect was supported by the downregulation of the PI3K/Akt pathway enabled by C6-ceramide and in contrast with C18-ceramide. The decrease of the migratory potential enabled by the targeted liposomal combinations is of high relevance in the context of TNBC, due to the underlying metastatic potential. Surprisingly, the nature of the drug interaction assessed at the level of bulk cancer cells revealed to be insufficient to predict whether a drug combination enables a decrease in the percentage of the master regulators of tumor relapse as ALDH^+/high putative TNBC cancer stem cells, suggesting, for the first time, that it should be extended further down to this level.

DNA damage independent inhibition of NF-κB transcription by anthracyclines

Anthracyclines are among the most used and effective anticancer drugs. Their activity has been attributed to DNA double-strand breaks resulting from topoisomerase II poisoning and to eviction of histones from select sites in the genome. Here, we show that the extensively used anthracyclines Doxorubicin, Daunorubicin, and Epirubicin decrease the transcription of nuclear factor kappa B (NF-κB)-dependent gene targets, but not interferon-responsive genes in primary mouse (Mus musculus) macrophages. Using an NMR-based structural approach, we demonstrate that anthracyclines disturb the complexes formed between the NF-κB subunit RelA and its DNA-binding sites. The anthracycline variants Aclarubicin, Doxorubicinone, and the newly developed Dimethyl-doxorubicin, which share anticancer properties with the other anthracyclines but do not induce DNA damage, also suppressed inflammation, thus uncoupling DNA damage from the effects on inflammation. These findings have implications for anticancer therapy and for the development of novel anti-inflammatory drugs with limited side effects for life-threatening conditions such as sepsis.

TPGS2000-DOX Prodrug Micelles for Improving Breast Cancer Therapy

Background

Doxorubicin (DOX) is an anthracycline antibiotic that inhibits the growth of several solid and hematologic malignant tumors. Increasing the targeting ability of DOX and reducing the multi-drug resistance (MDR) of tumor cells to DOX are major aims for researchers.

Purpose

In this study, to increase therapeutic efficiency, reduce the side effects and the MDR of tumor cells to DOX, D-alpha-tocopheryl polyethylene glycol 2000 succinate monoester (TPGS2000)-DOX prodrug micelles were developed by grafting DOX to TPGS2000 via an amide bond that release DOX in the slightly acidic conditions in tumor tissue.

Materials and Methods

The TPGS2000-DOX micelles were constructed using polyethylene glycol 12-hydroxy stearate (Solutol HS15) as the carrier. The in vitro drug release profile and dilution stability of the nanomicelles were determined. The in vitro cytotoxicity and distribution of the nanomicelles in the tumor cells were also investigated. Moreover, we explored the therapeutic outcomes using the MCF-7/ADR tumor-bearing murine model.

Results

The average particle size was approximately 30 nm with a narrow distribution, which was conducive for solid tumor accumulation. The results of in vivo imaging and in vitro cellular uptake assays demonstrated that the TPGS2000-DOX micelles increased the tumor-targeting ability and cellular uptake of DOX. The anticancer potential of TPGS2000-DOX micelles was higher than that of DOX, as revealed by in vitro cytotoxic assays with MCF-7/ADR cells and in vivo antitumor assays with MCF-7 tumor-bearing nude mice.

Conclusion

TPGS2000-DOX prodrug micelles reverse the MDR of tumor cells, achieve passive targeting by forming nanomicelles, and subsequently enhance the efficacy and reduce the toxicity of DOX.

A link between mitotic defects and mitotic catastrophe: detection and cell fate

Although the phenomenon of mitotic catastrophe was first described more than 80 years ago, only recently has this term been used to explain a mechanism of cell death linked to delayed mitosis. Several mechanisms have been suggested for mitotic catastrophe development and cell fate. Depending on molecular perturbations, mitotic catastrophe can end in three types of cell death, namely apoptosis, necrosis, or autophagy. Moreover, mitotic catastrophe can be associated with different types of cell aging, the development of which negatively affects tumor elimination and, consequently, reduces the therapeutic effect. The effective triggering of mitotic catastrophe in clinical practice requires induction of DNA damage as well as inhibition of the molecular pathways that regulate cell cycle arrest and DNA repair. Here we discuss various methods to detect mitotic catastrophe, the mechanisms of its development, and the attempts to use this phenomenon in cancer treatment.

Liposome-encapsulated anthraquinone improves efficacy and safety in triple negative breast cancer

Breast cancer is the most common cancer among women and a leading cause of death worldwide. Triple negative breast cancer (TNBC) is a highly aggressive subtype which is the most challenging to treat. Due to heterogeneity and a lack of specific molecular targets, small molecule-based chemotherapy is the preferred course of treatment. However, these drugs have high toxicity due to off-target effects on healthy tissues, and tumors may develop resistance. Here, we present a polyethylene glycol-modified nanoscale liposomal formulation (LipoRV) of a new anthraquinone derivative which has potent effects on multiple TNBC cell lines. LipoRV readily inhibited the cell cycle, induced cell apoptosis, and reduced long-term proliferative potential of TNBC cells. In a xenograft animal model, LipoRV successfully cleared tumors and demonstrated a good safety profile, without detrimental effects on biochemical markers. Finally, RNA sequencing of LipoRV-treated TNBC cells was carried out, indicating that LipoRV may have immunomodulatory properties. These findings demonstrate that a liposomal anthraquinone-based molecule has excellent promise for TNBC therapy in the future.

Ethyl acetate extract of Elephantopus mollis Kunth induces apoptosis in human gastric cancer cells

Background

Gastric cancer is one of the most leading causes of cancer death worldwide. Therefore, treatment studies have been being conducted, one of which is screening of novel agents from medicinal herbs. Elephantopus mollis Kunth (EM) belonging to Asteraceae family is a perennial herb with several therapeutic properties including anticancer activity. However, the effect of this species on gastric cancer has not been reported yet. In this study, cytotoxicity of different EM crude extracts was investigated on AGS gastric cancer cell line. Besides, the effects of extract on nuclear morphology, caspase-3 activation, and gene expression were also explored.

Results

The results showed that ethyl acetate extract exhibited a remarkably inhibitory ability (IC₅₀ = 27.5 μg/ml) on the growth of AGS cells, while causing less toxicity to normal human fibroblasts. The extract also induced apoptotic deaths in AGS cells as evidenced by cell shrinkage, formation of apoptotic bodies, nuclear fragmentation, caspase-3 activation, and the upregulation of BAK and APAF-1 pro-apoptotic genes related to mitochondrial signaling pathway. Specifically, BAK and APAF-1 mRNA expression levels showed 2.57 and 2.71-fold increases respectively.

Conclusions

The current study not only proved the anti-gastric cancer activity of EM ethyl acetate extract but also proposed its molecular mechanism. The extract could be a potential candidate for further investigation.

Study of synergistic effects of Ficus Carica leaves extract mediated chemo-photodynamic therapy on rhabdomyosarcoma cells

BACKGROUND

Chemotherapy for rhabdomyosarcoma (RD) is effective, but it has critical side effects and unavoidable challenges. Photodynamic therapy (PDT) is an approach to treating cancer with relatively moderate side effects. Plant products are a rich source of polyphenols, which have potent antioxidant and anticancer activities. Therefore, their research has become an emerging field in recent decades.

PURPOSE

This work aimed to evaluate the potential of hydrophobic extract of Ficus Carica (FC) to determine whether FC in the presence of low dose chemo and Aluminium Phthalocyanine (Photosense®) mediated photodynamic therapy synergistically enhances the treatment efficacy of RD cells.

METHOD

FC with and without combination with individual therapeutic modalities like photosense mediated photodynamic therapy, chemotherapy, and their combinations were studied for cell viability and morphological changes in invitro RD cells. A semiconductor diode laser (630 nm) was used as a light source in PDT. The cytotoxic effect of FC on cell viability and cellular morphological changes were investigated by MTT reagent and a camera attached to an inverted visible light microscope. The effect of FC, followed by di-combination with low dose chemo (doxorubicin-HCl, and dacarbazine), Photosense® mediated PDT and chemo-Photosense® mediated PDT (tri-combination) at 630 nm diode laser and 10 J/cm² fluency were also investigated by MTT reagent. The combination index method is used to identify the synergistic effect of combination therapy by using CompuSyn software based on the Chou-Talalay method.

RESULTS

The dose-dependent effect of FC on cell viability and cellular morphological changes were observed in the RD cell line. It was found that the pre incubation of FC potentiated the anticancer effect as a neoadjuvant agent for doxorubicin-HCl and decarbazine based chemotherapy, Photosense® mediated PDT and chemo-PDT (tri-combination) with synergistic effect (CI<1).

CONCLUSION

These results suggest a possible thread that the low dose combination of the aforementioned therapeutic modalities in the presence of FC remarkably enhances the treatment efficacy of RD in comparison with a single-agent treatment modality. The proposed sequence of FC with chemo and PDT might present better therapeutic outcomes in RD therapies and may provide result for RD metastasis. FC may also be used in the application of phyto-PDT to cancer in the future.

Dual targeting smart drug delivery system for multimodal synergistic combination cancer therapy with reduced cardiotoxicity

This study first reports the development of a smart drug delivery system (DDS) for multimodal synergistic cancer therapy combining chemo-photothermal-starvation approaches. A magnetic photothermal agent was synthesized by preparing iron oxide (IO) nanoparticles (NPs) with covalently attached indocyanine green (ICG) and glucose oxidase (GOx) (ICGOx@IO). Synthesized ICGOx@IO NPs were co-encapsulated with doxorubicin (Dox) and EGCG ((-)-epigallocatechin-3-gallate) inside PLGA (poly(lactic-co-glycolic acid)) NPs using multiple emulsion solvent evaporation method. Such formulation gave the advantage of triggered drug release by near-infrared (NIR) laser irradiation (808 nm at 1 W/cm²). RGD peptide was attached to the surface of PLGA NPs and the final hydrodynamic size was around 210 nm. Dual targeting by peptide and 240 mT external magnet significantly improved cellular uptake. Cellular uptake was observed using FACS, electron and optical microscopy. Dual targeting along with laser irradiation could reduce in vitro cell viability by 90 ± 2% (Dox-equivalent dose: 10 µg/ml) and complete tumor ablation was achieved in vivo due to synergetic therapeutic effect. Another attractive feature of the DDS was the significant reduction of cardiotoxicity of doxorubicin by EGCG. This new platform is thus expected to hold strong promise for future multimodal combination therapy of cancers. STATEMENT OF SIGNIFICANCE: Doxorubicin is one of the most studied and effective chemotherapeutic agents whose application is hindered due to its cardiotoxicity. In this study, we used (-)-Epigallocatechin-3-gallate (EGCG) to overcome that limitation. However, drug delivery to tumor sites with no/minimum accumulation in healthy organs is always challenging. Although peptide-based targeting is very popular, the effectiveness of receptor/ligand binding active targeting is sometimes questioned which motivated us to apply dual targeting approach. Multimodal therapies can exhibit synergistic effects and subsequently reduce the required dose of drug over monotherapy. We aimed to achieve chemo-photothermal-starvation combination therapy in this study and such achievement is yet to be reported. Our developed system also has the advantage of triggered drug release by near-infrared (NIR) laser irradiation.

Chlorogenic Acid Enhances Doxorubicin-Mediated Cytotoxic Effect in Osteosarcoma Cells

Despite the recurring outbreak of resistance mechanisms and adverse reactions, doxorubicin (Doxo) still remains the standard-of-care for several cancers, including osteosarcoma (OS). As an appealing source of phytochemical compounds, naturally occurring molecules have extensively been reported to overcome Doxo limitations in preclinical models. Unlike other dietary polyphenols, only few studies recognize chlorogenic acid (CGA) as a potential partner in combination therapy, while, conversely, its anticancer evidence is steadily growing, ultimately in OS. On this basis, herein we examine the cooperating effects between CGA and Doxo in U2OS and MG-63 human OS cells. With respect to Doxo alone, the concomitant administration of CGA further decreased cell viability and growth, promoting cell death potentially via apoptosis induction. Furthermore, a longer-lasting reduction in clonogenic potential deeply supported the CGA ability to improve Doxo efficacy in those cells. Remarkably, CGA treatment ameliorated Doxo-induced cytotoxicity in H9c2 rat cardiomyocyte cells instead. Although inactivation of p44/42 MAPK was detected in response to CGA plus Doxo, PD98059-mediated p44/42 MAPK impairment enhanced the combination outcome in OS cells. These findings firstly propose CGA as a promising chemosensitizer and cardioprotective agent in OS therapy, suggesting the p44/42 MAPK pathway as relevantly involved in CGA-mediated Doxo susceptibility.

Chemoprotective Effect of Daphnetin in Doxorubicin Treated Esophageal Cancer Stem Cell Xenograft Tumor Mouse

BACKGROUND

Chemotherapy drugs commonly used for cancer therapy, but chemotherapy has limitation due to side effects. Current studies suggest natural products are reducing the side effects of chemotherapy medicines. In this study, we examined the side effects of doxorubicin (Dox) in esophageal cancer cells (CSCs) derived tumors in vivo.

METHODS

Esophageal cancer cells (YMI) were treated in vitro with daphnetin (DAP) along with DOX. The MTT assay was used for estimating the cell viability and Annexin/7-AAD was used for the determination of apoptosis. Cell cycle arrest was conducted using the PI-staining method. The potential effect of DAP was evaluated by the estimation of oxidative stress such as total antioxidant capacity (TAC), malondialdehyde (MDA) and superoxide dismutase (SOD) and body weight in the xenograft mice.

RESULTS

DAP can protect Dox cell toxicity by suppressing cell apoptosis of ESCC. DAP arrest the cells as S-phase. In vivo experimental study showed that Dox simultaneously with DAP decreases the tumor size along with increased body weight in the nude mice compared to Dox alone treated group mice. Dox along with the DAP exhibited less systemic toxicity and reduced oxidative stress fraction circulation.

CONCLUSION

The result suggests that daphnetin may be used as an adjuvant therapy to reduce the systemic toxicity of chemotherapeutic agents, such as DOX, in stem cell treatment with ESCC cancer.

The Enhanced Efficacy of Intracellular Delivery of Doxorubicin/C6-Ceramide Combination Mediated by the F3 Peptide/Nucleolin System Is Supported by the Downregulation of the PI3K/Akt Pathway

Simple Summary

Targeted nanomedicine-based approaches that aim at the simultaneous delivery of synergistic drug combinations to multiple cellular populations are of high relevance for tackling heterogeneity on solid tumors. Considering that cancer stem cells (CSC) may originate from non-stem cancer cells, single-drug regimens targeting only one of these cell populations could enable tumors to evade treatments. As such, the identification of a common marker, such as nucleolin, might result in a therapeutic advantage. The results herein generated suggested a transversal role of nucleolin in the internalization of F3 peptide-targeted pegylated pH-sensitive liposomes into bulk ovarian cancer cells, including putative CSC-enriched ovarian cells. The intracellular delivery of a drug combination such as the one tested herein was relevant in the context of cell lines with higher intrinsic resistances to doxorubicin. The enhanced efficacy of the F3 peptide-targeted liposomal combination of doxorubicin/C6-ceramide was supported by the downregulation of the Akt pathway, within a specific range of basal level of expression.

Abstract

Targeting multiple cellular populations is of high therapeutic relevance for the tackling of solid tumors heterogeneity. Herein, the ability of pegylated and pH-sensitive liposomes, functionalized with the nucleolin-binding F3 peptide and containing doxorubicin (DXR)/C6-ceramide synergistic combination, to target, in vitro, ovarian cancer, including ovarian cancer stem cells (CSC), was assessed. The underlying molecular mechanism of action of the nucleolin-mediated intracellular delivery of C6-ceramide to cancer cells was also explored. The assessment of overexpression of surface nucleolin expression by flow cytometry was critical to dissipate differences identified by Western blot in membrane/cytoplasm of SKOV-3, OVCAR-3 and TOV-112D ovarian cancer cell lines. The former was in line with the significant extent of uptake into (bulk) ovarian cancer cells, relative to non-targeted and non-specific counterparts. This pattern of uptake was recapitulated with putative CSC-enriched ovarian SKOV-3 and OVCAR-3 sub-population (EpCAM^high/CD44^high). Co-encapsulation of DXR:C6-ceramide into F3 peptide-targeted liposomes improved cytotoxic activity relative to liposomes containing DXR alone, in an extent that depended on the intrinsic resistance to DXR and on the incubation time. The enhanced cytotoxicity of the targeted combination was mechanistically supported by the downregulation of PI3K/Akt pathway by C6-ceramide, only among the nucleolin-overexpressing cancer cells presenting a basal p-Akt/total Akt ratio lower than 1.

The lack of functional DNMT2/TRDMT1 gene modulates cancer cell responses during drug-induced senescence

Cellular senescence may be a side effect of chemotherapy and other anti-cancer treatments that may promote inflammation and paracrine secondary senescence in healthy tissues. DNMT2/TRDMT1 methyltransferase is implicated in the regulation of cellular lifespan and DNA damage response (DDR). In the present study, the responses to senescence inducing concentrations of doxorubicin and etoposide in different cancer cells with DNMT2/TRDMT1 gene knockout were evaluated, namely changes in the cell cycle, apoptosis, autophagy, interleukin levels, genetic stability and DDR, and 5-mC and NSUN1-6 levels. Moreover, the effect of azacytidine post-treatment was considered. Diverse responses were revealed that was based on type of cancer cells (breast and cervical cancer, osteosarcoma and glioblastoma cells) and anti-cancer drugs. DNMT2/TRDMT1 gene knockout in drug-treated glioblastoma cells resulted in decreased number of apoptotic and senescent cells, IL-8 levels and autophagy, and increased number of necrotic cells, DNA damage and affected DDR compared to drug-treated glioblastoma cells with unmodified levels of DNMT2/TRDMT1. We suggest that DNMT2/TRDMT1 gene knockout in selected experimental settings may potentiate some adverse effects associated with chemotherapy-induced senescence.

Understanding doxorubicin associated calcium remodeling during triple-negative breast cancer treatment: an in silico study

Aim:

Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer with high heterogeneity, rapid progression, and paucity of treatment options. The most effective chemotherapeutic drug used to treat TNBC is doxorubicin (Doxo) which is an anthracycline antibiotic. However, Doxo treatment alters cytosolic calcium dynamics leading to drug-resistance condition. The aim of this study is to capture the alterations in the activity of various calcium channels and pumps during Doxo treatment and their consequences on cytosolic calcium dynamics that ultimately result in drug resistance.

Methods:

In the present study, a mathematical model is proposed to capture the complex dynamical landscape of intracellular calcium during Doxo treatment. This study provides an insight into Doxo remodeling of calcium dynamics and associated drug-resistance effect. The model was first analyzed analytically and then explored through numerical simulation using techniques like global sensitivity analysis, parameter recalibration, etc.

Results:

The model is used to predict the potential combination therapy for Doxo that can overcome Doxo associated drug resistance. The results show targeting the dysregulated Ca²⁺ channels and pumps might provide efficient chemotherapy in TNBC. It was also observed that the indispensability of calcium influx rate is paramount in the Doxo drug resistance. Finally, three drugs were identified from existing literature that could be used as a combination therapy along with Doxo.

Conclusions:

The investigation highlights the importance of integrating the calcium signaling of various calcium regulating compounds for their effective anti-tumor effects deliverance along with chemotherapeutic agents. The results from this study might provide a new direction to the experimental biologists to explore different combination therapies with Doxo to enhance its anti-tumor effect.

Small Molecule Inhibitors Targeting Key Proteins in the DNA Damage Response for Cancer Therapy

DNA damage response (DDR) is a complicated interactional pathway. Defects that occur in subordinate pathways of the DDR pathway can lead to genomic instability and cancer susceptibility. Abnormal expression of some proteins in DDR, especially in the DNA repair pathway, are associated with the subsistence and resistance of cancer cells. Therefore, the development of small molecule inhibitors targeting the chief proteins in the DDR pathway is an effective strategy for cancer therapy. In this review, we summarize the development of small molecule inhibitors targeting chief proteins in the DDR pathway, particularly focusing on their implications for cancer therapy. We present the action mode of DDR molecule inhibitors in preclinical studies and clinical cancer therapy, including monotherapy and combination therapy with chemotherapeutic drugs or checkpoint suppression therapy.

Differential effects of cisplatin combined with the flavonoid apigenin on HepG2, Hep3B, and Huh7 liver cancer cell lines

The potential of apigenin (APG) to enhance cisplatin's (CDDP) chemotherapeutic efficacy was investigated in HepG2, Hep3B, and Huh7 liver cancer cell lines. The presence of 20 μM APG sensitized all cell lines to CDDP treatment (degree of sensitization based on the MTT assay: HepG2>Huh7>Hep3B). As reflected by sister chromatid exchange levels, the degree of genetic instability as well as DNA repair by homologous recombination differed among cell lines. CDDP and 20 μM APG cotreatment exhibited a synergistic genotoxic effect on Hep3B cells and a less than additive effect on HepG2 and Huh7 cells. Cell cycle delays were noticed during the first mitotic division in Hep3B and Huh7 cells and the second mitotic division in HepG2 cells. CDDP and CDDP + APG treatments reduced the clonogenic capacity of all cell lines; however, there was a discordance in drug sensitivity compared with the MMT assay. Furthermore, a senescence-like phenotype was induced, especially in Hep3B and Huh7 cells. Unlike CDDP monotherapy, the combined treatment exhibited a significant anti-invasive and anti-migratory action in all cancer cell lines. The fact that the three liver cancer cell lines responded differently, yet positively, to CDDP + APG cotreatment could be attributed to variations they present in gene expression. Complex mechanisms seem to influence cellular responses and cell fate.