Evaluation of Arsenic Trioxide Potential for Lung Cancer Treatment: Assessment of Apoptotic Mechanisms and Oxidative Damage

Arsenic trioxide-induced cytotoxicity in A549 cells: The role of necroptosis

INTRODUCTION

Lung cancer is one of the deadliest cancers globally. Arsenic trioxide (ATO) is still present as a highly effective drug in treating acute promyelocytic leukemia (APL). Chemotherapy resistance is one of the major problems in cancer therapy. Necroptosis, can overcomes resistance to apoptosis, and can promote cancer treatment. This study examines the necroptosis pathway in A549 cancer cells exposed to ATO.

METHODS

We used the MTT test to determine the ATO effects on the viability of A549 cells at three different time intervals. Also, the reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were performed in three-time intervals. The effect of ATO on apoptosis was evaluated by Annexin V / PI staining and, the RIPK1 and MLKL gene expression were measured by Real-Time PCR.

RESULTS

The ATO has dose and time-dependent cytotoxic effects, so at 24, 48, and 72 h, the IC50 doses were 33.81 '11.44 '2.535 µM respectively. A 50 μM ATO is the most appropriate to increase the MMP loss significantly at all three times. At 24 and 48 h after exposure of cells to ATO, the ROS levels increased. The RIPK1 gene expression increased significantly compared to the control group at concentrations of 50 and 100 μM; however, MLKL gene expression decreased.

CONCLUSIONS

The A549 cells, after 48 h exposure to ATO at 50 and 100 μM, induces apoptosis and necroptosis. Due to the reduced expression of MLKL, it can be concluded that ATO is probably effective in the metastatic stage of cancer cells.

125I seed implantation enhances arsenic trioxide-induced apoptosis and anti-angiogenesis in lung cancer xenograft mice

BACKGROUND AND PURPOSE

Arsenic trioxide (ATO) exerts anticancer effects on lung cancer. However, the clinical use of ATO is limited due to its systemic toxicity and resistance of lung cancer cells. The present study aimed to investigate the effects of ATO, alone and in combination with ¹²⁵I seed implantation on tumor growth and proliferation in lung cancer xenograft mice, and investigate the possible molecular mechanisms.

METHODS

The transmission electron microscope observed the tumor ultrastructure of lung cancer xenograft mice. The proliferation index of Ki-67 and the number and morphology of tumor microvessels were detected with immunohistochemical staining. The protein and mRNA expression were examined by western blot and real-time PCR assay.

RESULTS

The in vivo results demonstrated that ATO combined with ¹²⁵I seed significantly inhibited tumor growth and proliferation, as well as promoted apoptosis, and decreased the Ki-67 index and microvessel density in lung cancer xenograft mice. Moreover, ATO combined with ¹²⁵I seed decreased the protein and mRNA expression levels of HIF-1α, VEGF, and BCL-2, and increased those of BAX and P53.

CONCLUSIONS

ATO combined with ¹²⁵I seed significantly inhibited tumor growth and proliferation in lung cancer, which may be accomplished by inhibiting tumor angiogenesis and inducing apoptosis.

Olaparib synergizes with arsenic trioxide by promoting apoptosis and ferroptosis in platinum-resistant ovarian cancer

Poly (ADP-ribose) polymerase (PARP) inhibitors are efficacious in treating platinum-sensitive ovarian cancer (OC), but demonstrate limited efficiency in patients with platinum-resistant OC. Thus, further investigations into combined strategies that enhance the response to PARP inhibitors (PARPi) in platinum-resistant OC are required. The present study aimed to investigate the combined therapy of arsenic trioxide (ATO) with olaparib, a common PARPi, and determine how this synergistic cytotoxicity works in platinum-resistant OC cells. Functional assays demonstrated that the combined treatment of olaparib with ATO significantly suppressed cell proliferation and colony formation, and enhanced DNA damage as well as cell apoptosis in A2780-CIS and SKOV3-CIS cell lines. Results of the present study also demonstrated that a combination of olaparib with ATO increased lipid peroxidation and eventually triggered ferroptosis. Consistently, the combined treatment synergistically suppressed tumor growth in mice xenograft models. Mechanistically, ATO in combination with olaparib activated the AMPK α pathway and suppressed the expression levels of stearoyl-CoA desaturase 1 (SCD1). Collectively, results of the present study demonstrated that treatment with ATO enhanced the effects of olaparib in platinum-resistant OC.

Montelukast ameliorated pemetrexed-induced cytotoxicity in hepatocytes by mitigating endoplasmic reticulum (ER) stress and nucleotide oligomerization domain-like receptor protein 3 (NLRP3) activation

Pemetrexed (PEM) is an effective chemotherapeutic drug used for the treatment of clinical non-small-cell lung cancer (NSCLC) and is reported to induce severe hepatotoxicity. Exploring potential drugs which could counteract the side effects of PEM is of great clinical interest. Here, we aim to examine the beneficial effects of Montelukast, a novel anti-asthma drug, against PEM-induced cytotoxicity in hepatocytes, and to explore the underlying mechanism. We found that Montelukast reduces cytotoxicity of PEM in hepatocytes, confirmed by its increasing cell viability and reducing lactate dehydrogenase (LDH) release. In addition, Montelukast attenuated PEM-induced oxidative stress by reducing mitochondrial reactive oxygen species (ROS), increasing reduced glutathione (GSH), and downregulating NADPH oxidase 4 (NOX-4) expression. Importantly, Montelukast suppressed PEM-induced activation of the nucleotide oligomerization domain-like receptor protein 3 (NLRP3) inflammasome and mitigated endoplasmic reticulum (ER) stress by reducing NLRP3, growth arrest, and DNA damage-inducible protein 34 (GADD34), CEBP-homologous protein (CHOP), and also blocking the eukaryotic initiation factor 2 (eIF-2α)/activating transcription factor 4 (ATF4) signaling pathway. Lastly, we found that Montelukast inhibited the transcriptional activity of nuclear factor kappa-B (NF-κB). Montelukast exerted a protective action against PEM-induced cytotoxicity in hepatocytes by mitigating ER stress and NLRP3 activation.

F-box protein FBXO41 plays vital role in arsenic trioxide-mediated autophagic death of cancer cells

Arsenic trioxide (ATO), a potent anti-neoplastic drug, is known to prevent cancer cell growth through induction of autophagic cell death. However, importance of cellular factors in ATO-mediated autophagic cell death is poorly understood. In this study, using biochemical and immunofluorescence techniques, we show that F-box protein FBXO41 plays a critical role in anti-proliferative activity of ATO. Our study reveals the importance of FBXO41 in induction of autophagic death of cancer cells by ATO. Further, we show that the autophagic cell death induced by FBXO41 is distinct and independent of apoptosis and necrosis, showing that FBXO41 may play vital role in inducing autophagic death of apoptosis resistant cancer cells. Overall, our study elucidates the importance of FBXO41 in ATO induced autophagic cell death to prevent cancer progression, which could be explored to develop promising cancer therapeutic strategy.

Arsenic compound sensitizes homologous recombination proficient ovarian cancer to PARP inhibitors

The poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors show survival benefits in ovarian cancer patients with BRCA1/2 mutation or homologous recombination (HR) deficiency, but only limited efficacy in HR-proficient ones. Another drug, arsenic trioxide (ATO) or arsenic drug (RIF), exerts antitumor effects via inducing DNA damage. Here, we investigated the combined therapeutic effects of the PARP inhibitors and the arsenic compound in HR-proficient ovarian cancer. The combined treatment of niraparib, olaparib, or fluazolepali with ATO showed a significant suppression in tumor cell viability and colony formation. The drug treatment also induced synergistic inhibition of cell proliferation and DNA damage, and acceleration of cell apoptosis in two HR-proficient ovarian cancer cell lines SKOV3 and CAOV3, either by simultaneous or sequential administration. The mechanism underlying these synergistic effects were reflected by the significantly increased ratio of cleaved-PARP/total PARP and decreased ratio of p-AKT/total AKT. Consistently, the combination of olaparib with RIF synergistically reduced the tumor growth in mouse xenograft models. In conclusion, the arsenic compound greatly sensitizes HR-proficient ovarian cancer cells to the PARP inhibitors, and our findings provide an evidence for the clinical treatment development of this combination in HR-proficient ovarian cancer patients.

Paradoxical effects of arsenic in the lungs

High levels (> 100 ug/L) of arsenic are known to cause lung cancer; however, whether low (≤ 10 ug/L) and medium (10 to 100 ug/L) doses of arsenic will cause lung cancer or other lung diseases, and whether arsenic has dose-dependent or threshold effects, remains unknown. Summarizing the results of previous studies, we infer that low- and medium-concentration arsenic cause lung diseases in a dose-dependent manner. Arsenic trioxide (ATO) is recognized as a chemotherapeutic drug for acute promyelocytic leukemia (APL), also having a significant effect on lung cancer. The anti-lung cancer mechanisms of ATO include inhibition of proliferation, promotion of apoptosis, anti-angiogenesis, and inhibition of tumor metastasis. In this review, we summarized the role of arsenic in lung disease from both pathogenic and therapeutic perspectives. Understanding the paradoxical effects of arsenic in the lungs may provide some ideas for further research on the occurrence and treatment of lung diseases.

Deoxynivalenol-induced cell apoptosis monitoring using a cytochrome c-specific fluorescent probe based on a photoinduced electron transfer reaction

Deoxynivalenol (DON) is considered a mycotoxin that is toxic to the agricultural environment and human body. It is necessary to study the pathophysiological mechanism of DON toxicity at the cellular level. Cytochrome c (Cyt c), as an important biomarker of DON-induced apoptosis that may lead to a bipartite 'point-of-no return' event, is of great significance to be detected using cell imaging. Herein, we synthesized a DON-deactivated emission fluorescent probe, the molecularly imprinted polymer-coated quantum dots (CdTe@MIP), for monitoring the Cyt c level with a photoinduced electron transfer strategy. The CdTe@MIP probe can be easily loaded into cells and perform well due to its great sensitivity and selectivity and its fluorescence was gradually quenched with the increasing concentration (0-10 μM) and incubation time (0-7.5 h) of DON. Cell imaging results of apoptosis induced by DON was consistent with that of the cell counting kit-8 assay and flow cytometry technique. The developed method can be used to monitor DON-induced apoptosis and provide an early-warning system for the contaminant toxicity.

How does elevated water temperature affect fish brain? (A neurophysiological and experimental study: Assessment of brain derived neurotrophic factor, cFOS, apoptotic genes, heat shock genes, ER-stress genes and oxidative stress genes)

Water temperature is one of the most important environmental factors affecting the growth and survival of fish. Increased water temperature became a global problem and it is estimated that there will be an increase in water temperature due to global climate change. The physiological mechanism for the effects of high water temperature on the fish brain is not fully known. In the present study, fish were exposed to different temperatures (10 °C/15 °C/20 °C/25°) and brain tissues were sampled 2 h-4h-6h-8h per hour respectively and then we investigated transcriptional changes of BDNF, cFOS, apoptotic genes (caspase 3, Bax, Bcl2), heat shock genes (Hsp70 and Hsp 90) ER-Stress genes (grp78, atf6, and ire1) and oxidative stress genes (CAT, SOD, and GPx) and also immunoflourescence changes of BDNF and cFOSin rainbow trout brain. The results indicated that high temperature stress lead to physiological changes in the fish brain by causing a decrease in mRNA expression levels of CAT, SOD, GPx and Bcl2 and by causing an increase in mRNA expression of BDNF, cFOS, apoptotic genes (caspase 3, Bax), heat shock genes (Hsp70 and Hsp 90) ER-Stress genes (grp78, atf6, and ire1). This study will provide important information to elucidate the physiological mechanisms related to the effects of high water temperature on the fish brain.

An observational study on acceptability, palatability, and safety of Ayurveda immunity booster kit for the prevention of COVID-19 in frontline workers in Jaipur, India

Background

National Institute of Ayurveda, Jaipur, India, had distributed Ayurveda immunity booster kit (AIBK) (prepared at own pharmacy and comprising Chyawanprasha - 300 g, Vyadhi Kshamatva Kwatha - 300 g, and Vyadhi Kshamatva capsule - 30 g) for 15 days among the health-care workers, sanitation workers, and security and police staff engaged in the containment zones for prevention of COVID-19.

Aim

The aim of present study was to explore the medication that may be effective in prevention of the COVID -19. Hence, this study was done to assess the compliance of these medicines and their effects in the prevention of COVID-19.

Methods

One thousand seven hundred and fourteen frontline workers were provided with the AIBK for 15 days from April 24, 2020, to June 27, 2020. Data of frontline workers who had participated in AIBK and completed the treatment regimen with 2 weeks of follow-up after treatment with complete available data for safety, palatability, efficacy, and compliance were included in the study. Any adverse event needing hospitalization or medication, drug compliance and palatability, and appearance of the symptoms of COVID-19 or testing positive for COVID-19 were the outcome measures.

Results

Out of 1714 participants, 1003 participants were found to be eligible for this analysis. The median age of these participants was 39 years (range, 19-70), and males accounted for 90.1% (904 of 1003). A total of 7.5% of participants (75 of 1003) reported having adverse events after taking the study treatment. None of the participants reported any serious adverse effects after the administration of the AIBK. The acceptability of the AIBK was as high as 97.4%. None of the participants reported positive for COVID-19 results or COVID-19 symptoms up to 2 weeks of follow-up after completion of the study treatment.

Conclusion

The acceptability of AIBK is good and indicates its role in the prevention of COVID-19-like illness, hence further randomized control trials or cohort studies can be done to assess the mechanism of action and efficacy of AIBK as the preventive strategy in COVID-19.

Anticancer and antibacterial potential of robust Ruthenium(II) arene complexes regulated by choice of α-diimine and halide ligands

Several complexes of general formula [Ru(halide)(η⁶-p-cymene)(α-diimine)]⁺, in the form of nitrate, triflate and hexafluorophosphate salts, including a newly synthesized iodide compound, were investigated as potential anticancer drugs and bactericides. NMR and UV-Vis studies evidenced remarkable stability of the complexes in water and cell culture medium. In general, the complexes displayed strong cytotoxicity against A2780 and A549 cancer cell lines with IC₅₀ values in the low micromolar range, and one complex (RUCYN) emerged as the most promising one, with a significant selectivity compared to the non-cancerous HEK293 cell line. A variable affinity of the complexes for BSA and DNA binding was ascertained by spectrophotometry/fluorimetry, circular dichroism, electrophoresis and viscometry. The performance of RUCYN appears associated to enhanced cell internalization, favored by two cyclohexyl substituents, rather than to specific interaction with the evaluated biomolecules. The chloride/iodide replacement, in one case, led to increased cellular uptake and cytotoxicity at the expense of selectivity, and tuned DNA binding towards intercalation. Complexes with iodide or a valproate bioactive fragment exhibited the best antimicrobial profiles.

Exploration of the hepatoprotective effect and mechanism of magnesium isoglycyrrhizinate in mice with arsenic trioxide‑induced acute liver injury

Arsenic trioxide (ATO)-induced hepatotoxicity limits the therapeutic effect of acute myelogenous leukemia treatment. Magnesium isoglycyrrhizinate (MgIG) is a natural compound extracted from licorice and a hepatoprotective drug used in liver injury. It exhibits anti-oxidant, anti-inflammatory and anti-apoptotic properties. The aim of the present study was to identify the protective action and underlying mechanism of MgIG against ATO-induced hepatotoxicity. A total of 50 mice were randomly divided into five groups (n=10/group): Control; ATO; MgIG and high- and low-dose MgIG + ATO. Following continuous administration of ATO for 7 days, the relative weight of the liver, liver enzyme, histological data, antioxidant enzymes, pro-inflammatory cytokines, cell apoptosis and changes in Kelch-like ECH-associated protein 1/nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2) signaling pathway were observed. MgIG decreased liver injury, decreased the liver weight and liver index, inhibited oxidative stress and decreased the activity of glutathione, superoxide dismutase and catalase, production of reactive oxygen species and levels of pro-inflammatory cytokines, including IL-1β, IL-6 and TNF-α. Western blotting showed a decrease in Bax and caspase-3. There was decreased cleaved caspase-3 expression and increased Bcl-2 expression. MgIG notably activated ATO-mediated expression of Keap1 and Nrf2 in liver tissue. MgIG administration was an effective treatment to protect the liver from ATO-induced toxicity. MgIG maintained the level of Nrf2 in the liver and protected the antioxidative defense system to attenuate oxidative stress and prevent ATO-induced liver injury.

The protective role of autophagy against arsenic trioxide-induced cytotoxicity and ROS-dependent pyroptosis in NCTC-1469 cells

Arsenic trioxide (As2O3) is widely used in traditional Chinese medicine to treat tumors. This study investigated the effect of As(III) on pyroptosis in murine hepatocytes in vitro and how this relates to autophagy. NCTC1469-cells were treated with As(III) alone (6, 12 and 18 μM) or in combination with N-acetylcysteine (NAC,1 mM), 3-methyladenine (3-MA, 5 mM) or rapamycin (Rapa,100 nM) for 24 h. The results showed that As(III)-treatment reduced cell viability in a dose-dependent manner, but induced lactic dehydrogenase (LDH) activity. As(III)-treatment also resulted in increased intracellular reactive oxygen species (ROS) levels and decreased mitochondrial membrane potential (MMP), therefore promoting pyroptosis. Moreover, As(III)-treatment upregulated the expression of autophagy and pyroptosis-related genes (LC3-A, LC3-B, P62, Beclin-1, Atg5, Caspase-1, Gasdermin D, IL-18, IL-1β) and downregulated the expression of m-TOR, NLRP3, ASC genes. Meanwhile the accumulation of light chain 3-B/A (LC3B/LC3A), autophagy-related gene 5 (Atg-5), Bcl-2-interacting protein (Beclin-1), Caspase-1, Gasdermin D, interleukin-1β (IL-1β), IL-18 and poptosis-associated speck-like protein (ASC) proteins were upregulated while nucleotide binding and oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) was downregulated in all As(III)-treatment groups. Furthermore, the inhibition of autophagy by 3-MA aggravated AsIII-induced pyroptosis and cytotoxicity. However, NAC or Rapa markedly alleviated the abovementioned phenomenon under As(III) stress. In addition, we speculate that the protective mechanism of NAC on As(III)-induced pyroptosis in hepatocytes mainly include the elimination of ROS because of the chelation of As(III) in the culture medium. In conclusion, these results provide new insight into the mechanisms underlying AsIII-induced cytotoxicity and pyroptosis in hepatocytes in vitro.

Nitrogen and fluorine co-doped green fluorescence carbon dots as a label-free probe for determination of cytochrome c in serum and temperature sensing

As an important biomarker, the analysis of cytochrome c (Cyt c) plays a crucial role in cell-apoptosis or even cancer diagnosis. This work develops a label-free probe for Cyt c using the nitrogen and fluorine co-doped carbon dots (N, F-CDs) which were facile prepared through solvothermal method with 3, 4-difluorophenylhydrazine as precursor. The N, F-CDs have an average diameter of 3.4 nm, and can form a quite stable colloidal solution. The N, F-CDs show bright yellow-green fluorescence, excitation/emission wavelengths 475/530 nm, and a relatively high fluorescence quantum yield of 16.9%. Interestingly, the N, F-CDs indicate a linear and reversible variation of emission intensity with a sensitivity of -1.11% per ℃ in the temperature range from 25 to 60 ℃. Inner filter effect (IFE) between N, F-CDs and Cyt c turns the fluorescence of N, F-CDs from "on" to "off". The sensor possesses the excellent anti-interference ability towards the main components of plasma. Under optimum conditions, there is a linear relationship between fluorescence intensity function (F₀-F) and the concentration of Cyt c in the range of 0.5-25 μΜ with a limit of detection (LOD) (S/N = 3) of 0.25 μM. Finally, the developed method has been successfully used to detect Cyt c in human serum sample with satisfactory recoveries in a range of 93.14-110.40%.

A highly sensitive fluorescent biosensor for the detection of cytochrome c based on polydopamine nanotubes and exonuclease I amplification

A novel fluorescence method for the detection of Cyt c was developed based on PDANTs and exonuclease I amplification.

Arsenic trioxide as a novel anti-glioma drug: a review

Arsenic trioxide has shown a strong anti-tumor effect with little toxicity when used in the treatment of acute promyelocytic leukemia (APL). An effect on glioma has also been shown. Its mechanisms include regulation of apoptosis and autophagy; promotion of the intracellular production of reactive oxygen species, causing oxidative damage; and inhibition of tumor stem cells. However, glioma cells and tissues from other sources show different responses to arsenic trioxide. Researchers are working to enhance its efficacy in anti-glioma treatments and reducing any adverse reactions. Here, we review recent research on the efficacy and mechanisms of action of arsenic trioxide in the treatment of gliomas to provide guidance for future studies.

Long non-coding RNA ROR confers arsenic trioxide resistance to HepG2 cells by inhibiting p53 expression

Arsenic trioxide is an effective drug in the treatment of hematologic malignancies, but it has no obvious therapeutic effect on liver cancer. Long non-coding RNA ROR is a newly found long-noncoding RNA that has been reported to get involved in the regulation of chemo-resistance in multiple cancers. However, whether and how long non-coding RNA ROR gets involved in the resistance to arsenic trioxide in liver cancer has not been explored. In this study, We found that cellular apoptosis was increased by arsenic trioxide in liver cancer HepG2 cells; P53 expression was also increased by arsenic trioxide at both mRNA level and protein level, indicating that P53-dependent apoptosis is the main mechanism for arsenic trioxide to induce cytotoxicity in liver cancer HepG2 cells. Meanwhile, we found an obvious increase in the level of long non-coding RNA ROR in arsenic trioxide-treated HepG2 cells. By measuring the level of reactive oxygen species, glutathione, superoxide dismutase, and malondialdehyde, the product of lipid peroxidation, we further demonstrated that oxidative stress was a potential factor for both the activation of P53 expression and the increase in long non-coding RNA ROR expression. Through the knock-down of long non-coding RNA ROR by siRNA, we revealed that the activated long non-coding RNA ROR ameliorated arsenic trioxide-induced apoptosis by inhibiting P53 expression. Together, our study reported that long non-coding RNA ROR conferred arsenic trioxide resistance to liver cancer cells through inhibiting P53 expression, and long non-coding RNA ROR might be a novel sensitizing target for liver cancer treatment.

Trace Elements in Human Nutrition (II) - An Update

The dietary requirement for an essential trace element is an intake level which meets a specified criterion for adequacy and thereby minimizes risk of nutrient deficiency or excess. Disturbances in trace element homeostasis may result in the development of pathologic states and diseases. This article is an update of a review article “Trace Elements in Human Nutrition-A Review” previously published in 2013. The previous review was updated to emphasis in detail the importance of known trace elements so far in humans’ physiology and nutrition and also to implement the detailed information for practical and effective management of trace elements’ status in clinical diagnosis and health care situations. Although various classifications for trace elements have been proposed and may be controversial, this review will use World Health Organization( WHO) classification as previously done. For this review a traditional integrated review format was chosen and many recent medical and scientific literatures for the new findings on bioavailability, functions, and state of excess/deficiency of trace elements were assessed. The results indicated that for the known essential elements, essentiality and toxicity are unrelated and toxicity is a matter of dose or exposure. Little is known about the essentiality of some of the probably essential elements. In regard to toxic heavy metals, a toxic element may nevertheless be essential. In addition, the early pathological manifestations of trace elements deficiency or excess are difficult to detect until more specific pathologically relevant indicators become available. Discoveries and many refinements in the development of new techniques and continual improvement in laboratory methods have enabled researchers to detect the early pathological consequences of deficiency or excess of trace elements. They all are promises to fulfill the gaps in the present and future research and clinical diagnosis of trace elements deficiencies or intoxications. However, further investigations are needed to complete the important gaps in our knowledge on trace elements, especially probably essential trace elements’ role in health and disease status.

An extracellular pH-driven targeted multifunctional manganese arsenite delivery system for tumor imaging and therapy

Expanding the use of arsenic trioxide (ATO, As2O3) in cancer chemotherapy has received extensive attention in recent years owing to its remarkable efficacy in treating acute promyelocytic leukemia (APL). To date, the use of ATO for clinical treatment of solid tumors is still limited by its poor biocompatibility and severe toxic side effects. To address these limitations, here we developed a pH-low insertion peptide (pHLIP) modified ATO-based multifunctional drug-delivery system (DDS), which is termed MnAs@SiO2-pHLIP. With the coating of pHLIP, MnAs@SiO2-pHLIP could efficiently target the acidic tumor microenvironment, resulting in high intracellular accumulation of the DDS. As a "smart" nanoparticle (NP) platform, the DDS could controllably discharge the loaded ATO in response to acidic environments, which promotes the apoptosis of cancer cells. The features of controlled release capacity and the outstanding targeting ability contribute to better anticancer efficacy and less toxicity towards normal tissues compared with free ATO. It is worth noting that the acidic tumor microenvironment would also trigger the release of manganese ions (Mn2+) that brighten the T1 signal, which is exploited for real-time monitoring via contrast-enhanced magnetic resonance imaging (MRI). These multifunctional features, as demonstrated by both in vitro and in vivo experiments, could potentially expand the use of ATO to the treatment of solid tumors. We believe that MnAs@SiO2-pHLIP could serve as an auspicious agent for cancer theranostics and find tremendous applications in cancer management.

Kochia scoparia seed extract suppresses VEGF-induced angiogenesis via modulating VEGF receptor 2 and PI3K/AKT/mTOR pathways

Context: Kochia scoparia (L.) Schrad (Amaranthaceae), known as a traditional medicine in China, Japan and Korea, is reported to have various biological activities. However, K. scoparia seed extract (KSE) functional roles on angiogenesis and prostate cancer inhibition have not been elucidated. Objective: This study elucidates the effects of KSE on vascular endothelial growth factor (VEGF)-induced angiogenesis in human umbilical vein endothelial cells (HUVECs) and inhibition of proliferation in prostate cancer cells. Materials and methods: HUVECs were treated with 10-20 µg/mL of KSE and 20-50 ng/mL of VEGF for 12-72 h. Anti-angiogenesis properties of KSE were determined by wound healing, trans-well, tube formation, rat aortic ring assay and western blotting. Prostate cancer and normal cells were incubated with 10-250 µg/mL of KSE for 24 h, and cell viability was measured by SRB assay. Phenolic compounds in KSE were analyzed using a HPLC-PDA system. Results: IC₅₀ for cell viability of HUVECs, LNCaP, PC-3, RC-58T and RWPE-1 by KSE were 30.64, 89.25, 123.41, 141.62 and >250 µg/mL, respectively. Treatment with KSE (20 µg/mL) significantly suppressed VEGF-induced migration, invasion and capillary-like structure formation of HUVECs and microvessel sprouting from rat aortic rings. In addition, KSE down-regulated PI3K/AKT/mTOR levels and phosphorylation of VEGF receptor 2 in HUVECs. 3-OH-tyrosol (1.63 mg/g) and morin hydrate (0.17 mg/g) were identified in KSE. Conclusions: KSE inhibits angiogenesis in HUVECs as well as proliferation in human prostate cancer cells, suggesting KSE may be useful herbal medicine for preventing progression of prostate cancer and angiogenesis.

Arsenic trioxide inhibits angiogenesis in vitro and in vivo by upregulating FoxO3a

Arsenic trioxide (As₂O₃) has been used clinically for the treatment of acute promyelocytic leukemia and some solid tumors. However, the mechanisms of its anti-tumor effects are still elusive. Angiogenesis is a key process for tumor initiation, and increasing evidence has supported the role of anti-angiogenesis caused by arsenic in tumor suppression, although the detailed mechanism is not well understood. In the present study, we found that As₂O₃ significantly inhibited the angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro, and this was mediated by the upregulation of FoxO3a. Knockdown of FoxO3a could restore the angiogenic ability of HUVECs. Moreover, vascular endothelial cell-specific knockout of FoxO3a in mice could disrupt the anti-angiogenesis effect of As₂O₃ and endow the tumors with resistance to As₂O₃ treatments. Our results revealed a new mechanism by which As₂O₃ suppresses angiogenesis and tumor growth.

Traditional Chinese medicine-combination therapies utilizing nanotechnology-based targeted delivery systems: a new strategy for antitumor treatment

Cancer is a major public health problem, and is now the world’s leading cause of death. Traditional Chinese medicine (TCM)-combination therapy is a new treatment approach and a vital therapeutic strategy for cancer, as it exhibits promising antitumor potential. Nano-targeted drug-delivery systems have remarkable advantages and allow the development of TCM-combination therapies by systematically controlling drug release and delivering drugs to solid tumors. In this review, the anticancer activity of TCM compounds is introduced. The combined use of TCM for antitumor treatment is analyzed and summarized. These combination therapies, using a single nanocarrier system, namely codelivery, are analyzed, issues that require attention are determined, and future perspectives are identified. We carried out a systematic review of >280 studies published in PubMed since 1985 (no patents involved), in order to provide a few basic considerations in terms of the design principles and management of targeted nanotechnology-based TCM-combination therapies.

A candidate for lung cancer treatment: arsenic trioxide

Arsenic trioxide (ATO), a highly effective drug in treating acute promyelocytic leukemia with low toxicity, demonstrates a significant effect on lung cancer. The anti-cancer mechanisms of ATO include inhibition of cancer stem-like cells, induction of apoptosis, anti-angiogenesis, sensitization of chemotherapy and radiotherapy, anti-cancer effects of hypoxia, and immunoregulation properties. In addition, some studies have reported that different lung cancers respond differently to ATO. It was concluded on numerous studies that the rational combination of administration and encapsulation of ATO have promising potentials in increasing drug efficacy and decreasing adverse drug effects. We reviewed the efficacy of ATO in the treatment of lung cancer in recent years to provide some views for further study.

State of the science review of the health effects of inorganic arsenic: Perspectives for future research

Human exposure to inorganic arsenic (iAs) is a global health issue. Although there is strong evidence for iAs-induced toxicity at higher levels of exposure, many epidemiological studies evaluating its effects at low exposure levels have reported mixed results. We comprehensively reviewed the literature and evaluated the scientific knowledge on human exposure to arsenic, mechanisms of action, systemic and carcinogenic effects, risk characterization, and regulatory guidelines. We identified areas where additional research is needed. These priority areas include: (1) further development of animal models of iAs carcinogenicity to identify molecular events involved in iAs carcinogenicity; (2) characterization of underlying mechanisms of iAs toxicity; (3) assessment of gender-specific susceptibilities and other factors that modulate arsenic metabolism; (4) sufficiently powered epidemiological studies to ascertain relationship between iAs exposure and reproductive/developmental effects; (5) evaluation of genetic/epigenetic determinants of iAs effects in children; and (6) epidemiological studies of people chronically exposed to low iAs concentrations.

The crosstalk between trace elements with DNA damage response, repair, and oxidative stress in cancer

DNA damage response (DDR) is a regulatory system responsible for maintaining genome integrity and stability, which can sense and transduce DNA damage signals. The severity of damage appears to determine DDRs, which can include damage repair, cell-cycle arrest, and apoptosis. Furthermore, defective components in DNA damage and repair machinery are an underlying cause for the development and progression of various types of cancers. Increasing evidence indicates that there is an association between trace elements and DDR/repair mechanisms. In fact, trace elements seem to affect mediators of DDR. Besides, it has been revealed that oxidative stress (OS) and trace elements are associated with cancer development. In this review, we discuss the role of some critical trace elements in the risk of cancer. In addition, we provide a brief introduction on DDR and OS in cancer. Finally, we will further review the interactions between some important trace elements including selenium, zinc, chromium, cadmium, and arsenic, and DDR, and OS in cancer.

A review of arsenic exposure and lung cancer

As a well-established human carcinogen, arsenic has increased the risk of lung cancer over the past decades. Wide exposure to arsenic in the environment has attracted the attention of scientists. Its carcinogenicity at early life stages has been observed in certain animal studies already, yet current evidence is insufficient to extrapolate this to humans. Although the mechanisms of lung cancer induced by arsenic remain unclear, most of them are related to the biotransformation of arsenic, which would further provide target sites for precaution and therapy. This review comprehensively summarizes current studies associated to arsenic exposure and lung cancer and the mechanism of its carcinogenesis in lung cancer in three sections, namely, epidemiological studies, experimental studies, and mechanistic studies. In addition, prevention and treatment strategies as well as directions for future studies are discussed.

Arsenic trioxide induces the apoptosis and decreases NF-κB expression in lymphoma cell lines

Lymphoma is a type of cancer that develops from certain immune system cells. Arsenic trioxide (ATO) has attracted wide attention owing to its antitumor activities. However, the role of ATO in tumorigenesis and progression remains to be investigated. In the present study, the antitumor function of ATO was investigated in in lymphoma Raji and Jurkat cell lines and the effect of ATO on nuclear factor (NF)-κB expression levels. A Cell Counting kit-8 assay was used to assess cellular proliferation and the degree of cell apoptosis was measured by flow cytometric analysis; these assays demonstrated that ATO inhibited proliferation and promoted the apoptosis of Raji and Jurkat cells in a dose- and time-dependent manner. Western blot analysis revealed that ATO treatment affected the expression of apoptosis-associated proteins by downregulating the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2) and upregulating the pro-apoptotic protein Bcl-2-associatedX and the degree of caspase-3 cleavage. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis showed that the mRNA and protein expression levels of NF-κB were downregulated significantly following treatment with 2 µM ATO for 24, 48 and 72 h in the two cell lines. Additionally, immunofluorescence staining indicated that NF-κB expression diminished following ATO treatment in a time-dependent manner. These data indicated that ATO inhibited the proliferation of lymphoma cells by inducing cell apoptosis, which may be associated with the inhibition of the NF-κB signaling pathway. The findings of the present study may lay the foundation for developing a personalized medicine strategy using ATO via targeting of the NF-κB signaling pathway in lymphoma.

The different effects of natural pyrethrins and beta-cypermethrin on human hepatocyte QSG7701 cells by ROS-mediated oxidative damage

With the widespread use of natural pyrethrins and pyrethroids to defend pest insects, people had the sustained interest in the potential risk to environment and human health. However, the research about natural pyrethrins and beta-cypermethrin induction of cytotoxicity is still seldom. This study is about the cytotoxic effects of these on human non-target cells in vitro. The cytotoxic effect of natural pyrethrins and beta-cypermethrin on QSG7701 cells were researched by using various bioassays in vitro. The results suggested that with the natural pyrethrin concentration increased, the viability of QSG7701 cells were inhibited increasingly, and the IC₅₀ value as calculated was approximately 42.54 and 18.68 μg/mL after the cells were treated 24 and 48 h. The proliferative potential of QSG7701 cells treated with 40 μg/mL natural pyrethrins 6 and 12 h was decreased by 67.44 and 94.74%, dramatic enhancement ROS, collapse of mitochondrial membrane potential, DNA exhibit severity of impairment, and chromatin DNA condensation. However, beta-cypermethrin has lower toxicity than natural pyrethrins. The IC₅₀ values of beta-cypermethrin were all > 80 μg/mL, and the colony formation expression was decreased by 15.26 and 19.09%, which implied that natural pyrethrins are more significantly cytotoxic and potentially genotoxic to human hepatocyte cells.

Protective effects of timosaponin BII on oxidative stress damage in PC12 cells based on metabolomics

Peroxide and oxygen free radicals are some of the causes of oxidative stress in brain tissue, and could lead to the change of brain structure and function. In addition, oxidative damage is one of the most important causes of the aging of the vast majority of tissues. The aim of this study is to investigate the protective effect of timosaponin BII on oxidative stress damage of PC12 induced by H₂ O₂ using metabolomics based on the UHPLC-Q-TOF-MS technique. Partial least-squares discriminant analysis method was used to identify 35 metabolites as decisive marker compounds in a preliminary interpretation of the mechanism of the antioxidative effect of timosaponin BII. The majority of these metabolites are involved in the glutathione metabolism, amino acid metabolism, sphingolipid and glycerophospholipid metabolism. Our results suggest that timosaponin BII demonstrates systematic antioxidant effects in the PC12 oxidative damage cell model via the regulation of multiple metabolic pathways. These findings provide insight into the pathophysiological mechanisms underlying oxidative stress damage and suggest innovative and effective treatments for this disorder, providing a reliable basis for the development of novel therapeutic target in timosaponin BII treatment of oxidative stress.

Exosomal tetraspanins as regulators of cancer progression and metastasis and novel diagnostic markers

Exosomes are cell-cell communicators emerging as a new paradigm for noninvasive diagnosis and prognosis of treatment response. Exosomal tetraspanin proteins like CD63, CD9 and CD81 play a critical role in sorting, selective recruitment of biomolecules, target selection, cell-specific entry, capturing, angiogenesis and vasculogenesis. These tetraspanins are being used as markers for oral, colorectal and colon cancers and glioblastoma. However, exosomal markers with robust specificity for early detection of carcinomas are the furthest along. EXO CARTA database shows the presence of CD151 in exosomes of colorectal, melanoma, ovarian and prostate cancers. CD151 preferentially targets exosomes to lung, lymph node and stroma cells. The present review discussed the possible role of tetraspanins in the formation, cargo selection, target selection and uptake of exosomes and suggests exciting new directions for future research.

Arsenic trioxide-mediated suppression of miR-182-5p is associated with potent anti-oxidant effects through up-regulation of SESN2

Arsenic trioxide (ATO) is a traditional Chinese medicine that can induce oxidative stress for treatment of cancer cells. However, ATO may generate anti-oxidative responses to compromise the cytotoxic effect, but the underlying mechanisms remain unclear. Here we found that ATO could inhibit miR-182-5p expression in patient-derived primary S1 glioblastoma (GBM) cells accompanied by up-regulation of Sestrin-2 (SESN2) mRNA, a known anti-oxidant molecule. This phenomenon was also detected in a U87MG glioma cell line, human lung adenocarcinoma H1299 cell line and A549 cell line. Pretreatment with a free radical scavenger N-acetylcysteine (NAC) reduced the oxidative stress induced by ATO. Concomitantly, ATO mediated suppression of miR-182-5p and enhancement of SESN2 expression were also compromised. The MTT assay further showed that ATO induced cytotoxicity was enhanced by transfection of miR-182-5p mimics. Overexpression of miR-182-5p mimics significantly suppressed the expression of SENS2 and a firefly luciferase reporter gene fused to 3’- untranslated region (UTR) of SESN2 mRNA. Use of ribonucleoprotein immunoprecipitation (RNP-IP), ATO mediated suppression of miR-182-5p led to the stabilization of SESN2 mRNA as a result of Argonaute-2 (AGO2) dependent gene silencing. Furthermore, high expression of miR-182-5p and low expression of SESN2 mRNA tend to be associated with longer survival of glioma or lung cancer patients using public available gene expression datasets and online tools for prediction of clinical outcomes. Taken together, current data suggest that the miR-182-5p/SENS2 pathway is involved in ATO induced anti-oxidant responses, which may be important for the design of novel strategy for cancer treatment.

Multifactorial Modes of Action of Arsenic Trioxide in Cancer Cells as Analyzed by Classical and Network Pharmacology

Arsenic trioxide is a traditional remedy in Chinese Medicine since ages. Nowadays, it is clinically used to treat acute promyelocytic leukemia (APL) by targeting PML/RARA. However, the drug's activity is broader and the mechanisms of action in other tumor types remain unclear. In this study, we investigated molecular modes of action by classical and network pharmacological approaches. CEM/ADR5000 resistance leukemic cells were similar sensitive to As2O3 as their wild-type counterpart CCRF-CEM (resistance ratio: 1.88). Drug-resistant U87.MG ΔEGFR glioblastoma cells harboring mutated epidermal growth factor receptor were even more sensitive (collateral sensitive) than wild-type U87.MG cells (resistance ratio: 0.33). HCT-116 colon carcinoma p53-/- knockout cells were 7.16-fold resistant toward As2O3 compared to wild-type cells. Forty genes determining cellular responsiveness to As2O3 were identified by microarray and COMPARE analyses in 58 cell lines of the NCI panel. Hierarchical cluster analysis-based heat mapping revealed significant differences between As2O3 sensitive cell lines and resistant cell lines with p-value: 1.86 × 10-5. The genes were subjected to Galaxy Cistrome gene promoter transcription factor analysis to predict the binding of transcription factors. We have exemplarily chosen NF-kB and AP-1, and indeed As2O3 dose-dependently inhibited the promoter activity of these two transcription factors in reporter cell lines. Furthermore, the genes identified here and those published in the literature were assembled and subjected to Ingenuity Pathway Analysis for comprehensive network pharmacological approaches that included all known factors of resistance of tumor cells to As2O3. In addition to pathways related to the anticancer effects of As2O3, several neurological pathways were identified. As arsenic is well-known to exert neurotoxicity, these pathways might account for neurological side effects. In conclusion, the activity of As2O3 is not restricted to acute promyelocytic leukemia. In addition to PML/RARA, numerous other genes belonging to diverse functional classes may also contribute to its cytotoxicity. Network pharmacology is suited to unravel the multifactorial modes of action of As2O3.

Regulation of ABCG2 by nuclear factor kappa B affects the sensitivity of human lung adenocarcinoma A549 cells to arsenic trioxide

Arsenic trioxide (As₂O₃) is successfully used as an anticancer agent against acute promyelocytic leukemia and some solid tumors. However, the application of As₂O₃ is largely limited by its drug resistance in the treatment of non-small cell lung carcinoma (NSCLC). Therefore, it is an urgent task to enhance the sensitivity of lung cancer cells to As₂O₃. In this study, using human lung adenocarcinoma A549 cells as a cell culture model, we demonstrated that an adenosine triphosphate binding cassette (ABC) transporter, ABCG2, was significantly increased by As₂O₃ treatment, while other ABC transporters, ABCB1 and ABCC1 showed no remarkable change in the response to As₂O₃. After inhibition of ABCG2 by its specific inhibitor, the drug sensitivity of As₂O₃ to A549 cells was significantly enhanced, manifested by decreased cell viability and colony formation as well as the increased ROS production and cell apoptosis. To further understand the molecular mechanism underlying the elevation of ABCG2 expression in As₂O₃-treated cells, we detected the activation state of nuclear factor kappa B (NF-κB) pathway and its relationship with ABCG2 expression. Our results revealed that the increased expression of ABCG2 was regulated by NF-κB, and thus affecting the cell death of As₂O₃-treated A549 cells. These findings indicate that inhibition of NF-κB/ABCG2 pathway by specific inhibitors may be a new strategy for the improvement of As₂O₃ sensitivity in NSCLC treatment.

Auriculasin-induced ROS causes prostate cancer cell death via induction of apoptosis

Recent studies have demonstrated that natural agents targeting the accumulation of reactive oxygen species (ROS) that selectively kill, leaving normal cells undamaged, can suppress prostate cancer. Here, we show that auriculasin, derived from Flemingia philippinensis, induces significant cell death and apoptosis via ROS generation in prostate cancer cells. Auriculasin treatment resulted in selective apoptotic cell death in LNCaP prostate cancer cells, characterized by DNA fragmentation, accumulation of sub-G1 cell population, cleavage of poly (ADP-ribose) polymerase (PARP), regulation of Bax/Bcl-2 ratio, increase of cytosolic apoptosis-inducing factor (AIF) and endonuclease G (EndoG), in addition to inhibiting tumor growth in a xenograft mouse model. Interestingly, auriculasin-induced apoptosis did not result in caspase-3, -8, and -9 activations. We found that auriculasin treatment decreased phosphorylation of AKT/mTOR/p70s6k in a dose- and time-dependent manner. Further, cellular ROS levels increased in LNCaP cells treated with auriculasin and blocking ROS accumulation with ROS scavengers resulted in inhibition of auriculasin-induced PARP cleavage, AIF increase, upregulation of Bax/Bcl-2 ratio, and decrease in AKT/mTOR phosphorylation. Taken together, these data suggest that auriculasin targets ROS-mediated caspase-independent pathways and suppresses PI3K/AKT/mTOR signaling, which leads to apoptosis and decreased tumor growth.

Dihydroartemisinin Sensitizes Human Lung Adenocarcinoma A549 Cells to Arsenic Trioxide via Apoptosis

Recent studies have shown that arsenic trioxide (ATO) is an effective anti-cancer drug for treatment of acute promyelocytic leukemia and other types of human cancer. However, we have found that lung cancer cells constantly develop a high level of resistance to ATO. In this study, we have explored a possibility of combination of dihydroartemisinin (DHA) and ATO treatments to reduce ATO resistance of lung cancer cells. We determined the combinatory effects of DHA and ATO on cytotoxicity of human lung adenocarcinoma (A549) cells. We showed that co-exposure to DHA and ATO of A549 cells synergistically increased the cytotoxicity and apoptotic cell death in the cells. We found that the synergistic effect of DHA and ATO in promoting apoptosis mainly resulted from increased cellular level of reactive oxygen species (ROS) and DNA damage. ATO alone only exerted moderate growth inhibitory effects on A549 cells. The results indicate that DHA can significantly sensitize ATO-induced cytotoxicity of A549 lung cancer cells through apoptosis mediated by ROS-induced DNA damage. Interestingly, we found that the combinatory treatment of DHA and ATO did not result in significant adverse effects in normal human bronchial epithelial (HBE) cells. Our results further provide evidence for the potential application of combinatory effects of DHA and ATO as a safe therapy for human lung cancer.

Arsenic trioxide exposure impairs testicular morphology in adult male mice and consequent fetus viability

The acute promyelocytic leukemia (APL) is a rare disease, affecting 0.1/100,000 individuals globally. Despite significant advances in APL therapy, some patients still experience relapsed disease. Currently, arsenic trioxide (As₂O₃) was found to be effective in relapsed APL treatment and considered as standard treatment for these cases. However, it has been shown that exposure to As₂O₃ may exert adverse effects on the male reproductive system since this substance might also induce apoptosis of other important cell types including stem cells. Studies demonstrated that treatment with this metallic substance decreased plasma levels of testosterone and interfered with sperm parameters such as concentration, motility, and viability. In addition, As₂O₃ was found to produce significant damage to spermatocytes, which may be associated with testicular toxicity and consequent inhibition of spermatogenesis. The aim of this study was to determine sub-chronic treatment effects of As₂O₃ on sperm and testicular morphology, androgen receptor (AR) immunoreactivity in testes and epididymis, in addition to evaluation of fertility parameters in adult male mice. Thirty adult Swiss mice were divided into three experimental groups: control; received distilled water (vehicle) while treated received 0.3 or 3 mg/kg/day As₂O₃ subcutaneously, for 5 days per week, followed by 2 days of interruption, for 5 weeks. Results showed that As₂O₃ (1) decreased spermatozoa number, (2) produced seminiferous epithelium degeneration and exfoliation of germ cells tubule lumen (3) altered nucleus/cytoplasm proportion of Leydig cells and (4) reduced AR immunoreactivity in both Leydig and epithelial epididymal cells. Further, fetal viability tests demonstrated an increase in post-implantation loss in females that were mated with As₂O₃-treated males. Data indicate that As₂O₃ exposure altered the spermatogenic process and subsequently fetal viability.

miR-155 mediates arsenic trioxide resistance by activating Nrf2 and suppressing apoptosis in lung cancer cells

Arsenic trioxide (ATO) resistance is a challenging problem in chemotherapy. However, the underlying mechanisms remain to be elucidated. In this study, we identified a high level of expression of miR-155 in a human lung adenocarcinoma A549R cell line that is highly resistant to ATO. We showed that the high level of miR-155 was associated with increased levels of cell survival, colony formation, cell migration and decreased cellular apoptosis, and this was mediated by high levels of Nrf2, NAD(P)H quinone oxidoreductase 1 (NQO1), heme oxygenase-1 (HO-1) and a high ratio of Bcl-2/Bax. Overexpression of the miR-155 mimic in A549R cells resulted in increased levels of colony formation and cell migration as well as reduced apoptosis along with increased Nrf2, NQO1 and HO-1. In contrast, silencing of miR-155 expression with its inhibitor in the cells, significantly decreased the cellular levels of Nrf2, NQO1 and HO-1 as well as the ratio of Bcl-2/Bax. This subsequently reduced the level of colony formation and cell migration facilitating ATO-induced apoptosis. Our results indicate that miR-155 mediated ATO resistance by upregulating the Nrf2 signaling pathway, but downregulating cellular apoptosis in lung cancer cells. Our study provides new insights into miR-155-mediated ATO resistance in lung cancer cells.

Recent advances in cytochrome c biosensing technologies

This review is an attempt, for the first time, to describe advancements in sensing technology for cytochrome c (cyt c) detection, at point-of-care (POC) application. Cyt c, a heme containing metalloprotein is located in the intermembrane space of mitochondria and released into bloodstream during pathological conditions. The release of cyt c from mitochondria is a key initiative step in the activation of cell death pathways. Circulating cyt c levels represents a novel in-vivo marker of mitochondrial injury after resuscitation from heart failure and chemotherapy. Thus, cyt c detection is not only serving as an apoptosis biomarker, but also is of great importance to understand certain diseases at cellular level. Various existing techniques such as enzyme-linked immunosorbent assays (ELISA), Western blot, high performance liquid chromatography (HPLC), spectrophotometry and flow cytometry have been used to estimate cyt c. However, the implementation of these techniques at POC application is limited due to longer analysis time, expensive instruments and expertise needed for operation. To overcome these challenges, significant efforts are being made to develop electrochemical biosensing technologies for fast, accurate, selective, and sensitive detection of cyt c. Presented review describes the cutting edge technologies available in the laboratories to detect cyt c. The recent advancements in designing and development of electrochemical cyt c biosensors for the quantification of cyt c are also discussed. This review also highlights the POC cyt c biosensors developed recently, that would prove of interest to biologist and therapist to get real time informatics needed to evaluate death process, diseases progression, therapeutics and processes related with mitochondrial injury.