Oxidative stress in leukemia and antioxidant treatment

Boric Acid Affects Cell Proliferation, Apoptosis, and Oxidative Stress in ALL Cells

T-cell acute lymphoblastic leukemia (T-ALL) is a type of acute lymphoblastic leukemia from early T-cell progenitors. Interest grows in creating less toxic agents and therapies for chemo-resistant T-ALL cancer. Recently, elemental boron has special properties useful in the creation of new drugs. Studies have revealed the cytotoxic properties of boric acid (BA) on cancer, but not fully understood. We aimed to investigate the effect of BA on cell proliferation, apoptosis, and oxidative stress in the Jurkat cells. The effects of BA on cell viability were determined by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay for 24-48-72 h. The impact of BA on apoptosis was analyzed by acridine orange/ethidium bromide. Expression of apoptosis regulatory genes (Bcl-2, Bax, Caspase-3-8-9) and apoptotic miRNA (miR-21) was used by real-time quantitative polymerase chain reaction (RT-qPCR). The total oxidant status (TOS), total antioxidant status (TAS), and the oxidative stress index (OSI) value were calculated for oxidative stress. We determined the cytotoxic activity of BA on Jurkat cells by using XTT and defined the IC50 concentration (802.7 μg/mL) of BA. The findings clearly show that BA inhibited Jurkat cell proliferation dose-dependently. BA induced apoptosis through downregulated anti-apoptotic genes, and upregulated pro-apoptotic genes. Additionally, we found that BA significantly reduced the expression of miR-21 (p<0.001). Our findings demonstrated that different doses of BA increased TAS levels while decreasing TOS levels in Jurkat cells. Our study suggests that BA might be potential anti-cancer agent candidate in ALL via inhibition of cell proliferation, induced apoptosis, and reducing the amounts of anti-oxidants in cells.

Interaction of olive oil-based propolis and caffeic acid phenethyl ester with methylprednisolone used in the treatment of human acute myeloid leukemia

BACKGROUND

Methylprednisolone (MP) is a pharmaceutical agent employed in the management of Leukemia, which is a systemic malignancy that arises from abnormalities in the hematological system. Numerous investigations in the field of cancer research have directed their attention towards propolis, a natural substance with significant potential as a treatment-supportive agent. Its utilization aims to mitigate the potential adverse effects associated with chemotherapy medications. The objective of this study was to examine the impact of olive oil-based propolis (OEP) and caffeic acid phenethyl ester (CAPE) on the treatment of acute myeloid leukemia, as well as to determine if they exhibit a synergistic effect when combined with the therapeutic support product methylprednisolone.

METHODS AND RESULTS

The proliferation of HL-60 cells was quantified using the WST-8 kit. The PI Staining technique was employed to do cell cycle analysis of DNA in cells subjected to OEP, CAPE, and MP, with subsequent measurement by flow cytometry. The apoptotic status of cells was determined by analyzing them using flow cytometry after staining with the Annexin V-APC kit. The quantification of apoptotic gene expression levels was conducted in HL-60 cells. In HL-60 cells, the IC50 dosages of CAPE and MP were determined to be 1 × 10- 6 M and 5 × 10- 4 M, respectively. The HL-60 cells were subjected to apoptosis and halted in the G0/G1 and G2/M phases of the cell cycle after being treated with MP, CAPE, and OEP.

CONCLUSIONS

Propolis and its constituents have the potential to serve as effective adjunctive therapies in chemotherapy.

Salvianolic acid A attenuates arsenic-induced ferroptosis and kidney injury via HIF-2α/DUOX1/GPX4 and iron homeostasis

Arsenic (As) is a prevalent pollutant in the environment and causes a high frequency of kidney disease in areas of high arsenic contamination, but its pathogenic mechanisms have yet to be completely clarified. Ferroptosis is a new form of cell death mainly dependent on lipid peroxidation and iron accumulation. Several reports have suggested that ferroptosis is operative in a spectrum of diseases caused by arsenic exposure, including in the lungs, pancreas, and testis. However, the mechanism and exact role of ferroptosis in arsenic-induced kidney injury is not known. Firstly, by constructing in vivo and in vitro arsenic exposure models, we confirmed the occurrence of ferroptosis based on the identification of the ability of NaASO2 to cause kidney injury. In addition, we found that arsenic exposure could upregulate DUOX1 expression in kidney and HK-2 cells, and after knocking down DUOX1 using siRNA was able to significantly upregulate GPX4 expression and attenuate ferroptosis. Subsequently using bioinformatics, we identified and proved the involvement of HIF-2α in the course of ferroptosis, and further confirmed by dual luciferase assay that HIF-2α promotes DUOX1 transcription to increase its expression. Finally, intervention with the natural ingredient SAA significantly attenuated arsenic-induced ferroptosis and kidney injury. These results showed that arsenic could cause ferroptosis and kidney injury by affecting HIF-2α/DUOX1/GPX4 and iron homeostasis and that SAA was an effective intervention component. This study not only discovered the molecular mechanism of sodium arsenite-induced kidney injury but also explored an active ingredient with intervention potential, providing a scientific basis for the prevention and treatment of sodium arsenite-induced kidney injury.

GingerenoneA overcomes dexamethasone resistance by activating apoptosis and inhibiting cell proliferation in pediatric T-ALL cells

Plant-based combination strategies have been widely considered in cancer therapy to attenuate chemotherapeutics side effects. The anti-leukemic effect of the whole ginger extract was previously portrayed by our team, and the current study is centered around the cytotoxicity and mechanism of action of a phenolic subsidiary of ginger, GingerenoneA, on pediatric acute lymphoblastic leukemia. GingernoneA imposed, dose-dependently, inhibitory effects on the viability of T and B leukemia cell lines confirmed by MTT assays. Resistance to Dexamethasone, a mostly used chemotherapeutic in acute lymphoblastic leukemia treatments, was overcome by GingernoneA. A synergistic effect of Dexamethasone and GingrenoneA on T leukemia cell lines and patient primary cells was confirmed. Annexin-V/PI and acridine orange/ethidium bromide staining illustrated dose-dependent apoptosis in CCRF-CEM cells developed by GingerenoneA. The intrinsic and extrinsic apoptosis induction and antiproliferative attribution of GingerenoneA were validated by western blot and qPCR. Despite the supposed loss of function in CCRF-CEM cells, TP53 showed increased expression levels and functional activity upon treatment with GingernoneA. Bioinformatic studies revealed the conceivable impact of GingerenoneA on the reactivity of mutant P53 through its binding to Cys124. Our findings may provide novel strategies for therapeutic intervention to ameliorate pALL outcomes.

Drug-induced oxidative stress in cancer treatments: Angel or devil?

Oxidative stress (OS), defined as redox imbalance in favor of oxidant burden, is one of the most significant biological events in cancer progression. Cancer cells generally represent a higher oxidant level, which suggests a dual therapeutic strategy by regulating redox status (i.e., pro-oxidant therapy and/or antioxidant therapy). Indeed, pro-oxidant therapy exhibits a great anti-cancer capability, attributing to a higher oxidant accumulation within cancer cells, whereas antioxidant therapy to restore redox homeostasis has been claimed to fail in several clinical practices. Targeting the redox vulnerability of cancer cells by pro-oxidants capable of generating excessive reactive oxygen species (ROS) has surfaced as an important anti-cancer strategy. However, multiple adverse effects caused by the indiscriminate attacks of uncontrolled drug-induced OS on normal tissues and the drug-tolerant capacity of some certain cancer cells greatly limit their further applications. Herein, we review several representative oxidative anti-cancer drugs and summarize their side effects on normal tissues and organs, emphasizing that seeking a balance between pro-oxidant therapy and oxidative damage is of great value in exploiting next-generation OS-based anti-cancer chemotherapeutics.

Ferroptosis in acute leukemia

ABSTRACT

Ferroptosis is an iron-dependent cell death pathway that is different from apoptosis, pyroptosis, and necrosis. The main characteristics of ferroptosis are the Fenton reaction mediated by intracellular free divalent iron ions, lipid peroxidation of cell membrane lipids, and inhibition of the anti-lipid peroxidation activity of intracellular glutathione peroxidase 4 (GPX4). Recent studies have shown that ferroptosis can be involved in the pathological processes of many disorders, such as ischemia-reperfusion injury, nervous system diseases, and blood diseases. However, the specific mechanisms by which ferroptosis participates in the occurrence and development of acute leukemia still need to be more fully and deeply studied. This article reviews the characteristics of ferroptosis and the regulatory mechanisms promoting or inhibiting ferroptosis. More importantly, it further discusses the role of ferroptosis in acute leukemia and predicts a change in treatment strategy brought about by increased knowledge of the role of ferroptosis in acute leukemia.

Connexin 43-modified bone marrow stromal cells reverse the imatinib resistance of K562 cells via Ca 2+ -dependent gap junction intercellular communication

BACKGROUND

Imatinib mesylate (IM) resistance is an emerging problem for chronic myeloid leukemia (CML). Previous studies found that connexin 43 (Cx43) deficiency in the hematopoietic microenvironment (HM) protects minimal residual disease (MRD), but the mechanism remains unknown.

METHODS

Immunohistochemistry assays were employed to compare the expression of Cx43 and hypoxia-inducible factor 1α (HIF-1α) in bone marrow (BM) biopsies of CML patients and healthy donors. A coculture system of K562 cells and several Cx43-modified bone marrow stromal cells (BMSCs) was established under IM treatment. Proliferation, cell cycle, apoptosis, and other indicators of K562 cells in different groups were detected to investigate the function and possible mechanism of Cx43. We assessed the Ca 2+ -related pathway by Western blotting. Tumor-bearing models were also established to validate the causal role of Cx43 in reversing IM resistance.

RESULTS

Low levels of Cx43 in BMs were observed in CML patients, and Cx43 expression was negatively correlated with HIF-1α. We also observed that K562 cells cocultured with BMSCs transfected with adenovirus-short hairpin RNA of Cx43 (BMSCs-shCx43) had a lower apoptosis rate and that their cell cycle was blocked in G0/G1 phase, while the result was the opposite in the Cx43-overexpression setting. Cx43 mediates gap junction intercellular communication (GJIC) through direct contact, and Ca 2+ is the key factor mediating the downstream apoptotic pathway. In animal experiments, mice bearing K562, and BMSCs-Cx43 had the smallest tumor volume and spleen, which was consistent with the in vitro experiments.

CONCLUSIONS

Cx43 deficiency exists in CML patients, promoting the generation of MRD and inducing drug resistance. Enhancing Cx43 expression and GJIC function in the HM may be a novel strategy to reverse drug resistance and promote IM efficacy.

The trace that is valuable: serum copper and copper to zinc ratio for survival prediction in younger patients with newly diagnosed acute myeloid leukaemia

PURPOSE

No data on predicting the survival of AML patients based on the level of trace elements in the serum have been presented to date. The aims of this prospective cohort study were as follows: (i) to evaluate the serum Cu and Zn levels in people from Northeast China, (ii) to assess the association between the serum Cu level (SCL) and Cu to Zn ratio (SCZR) and clinical and nutrition data, and (iii) to investigate the predictive values of the SCL and SCZR in newly diagnosed de novo AML patients.

METHODS

A total of 105 newly diagnosed AML patients and 82 healthy controls were recruited. The serum Cu and Zn levels were determined by inductively coupled plasma spectrometry. The associations of SCL and SCZR with the survival of these AML patients were assessed by Cox proportional hazards models.

RESULTS

Both SCL and SCZR were positively related to the blast percentage of bone marrow and C-reactive protein, negatively related to albumin level and CEBPA double mutation and were significantly associated with worse overall survival and disease-free survival. Meanwhile, patients with higher SCL had worse CTCAE levels, and patients with higher SCZR showed less complete remission during the first course of induction chemotherapy. Moreover, higher SCZR was positively associated with ELN risk stratification, and was negatively associated with haemoglobin level and prognostic nutritional index (PNI).

CONCLUSION

The SCL and SCZR are associated with long-term survival in patients with newly diagnosed AML undergoing intensive induction and may serve as important predictive biomarkers.

Ellagic acid: insight into its protective effects in age-associated disorders

The disparity in the free radical generation and the production of antioxidants to counteract its effect is known as oxidative stress. Oxidative stress causes damage to the macromolecules such as lipids, carbohydrates, proteins, and DNA and RNA. The oxidative damage to the cellular components leads to a process of aging and various age-associated disorders. The literature survey for this review was done using PubMed, Google Scholar, and Science Direct. The papers showing the studies related to aging and age-associated disorders have been selected for reviewing this paper. Ellagic acid has been used as the keyword, and more emphasis has been put on papers from the last 10 years. However, some papers with significant studies prior to 10 years have also been considered. Almost 250 papers have been studied for reviewing this paper, and about 135 papers have been cited. Ellagic acid (EA) is present in high quantities in pomegranate and various types of berries. It is known to possess the antioxidant potential and protects from the harmful effects of free radicals. Various studies have shown its effect to protect cardiovascular, neurodegenerative, cancer, and diabetes. The present review focuses on the protective effect of ellagic acid in age-associated disorders. The effect of EA has been studied in various chronic disorders but the scope of this review is limited to cancer, diabetes, cardiovascular and neurodegenerative disorders. All the disease aspects have not been addressed in this particular review.

Oxidative Stress in Chronic Hepatitis B—An Update

In recent years, the role of oxidative stress has been investigated in an increasing number of infections. There is a close link between the inflammation that accompanies infections and oxidative stress. Excessive reactive oxygen species induce harmful effects on cell components, including lipids, proteins, and nucleic acids. A growing body of evidence attests to the role of oxidative stress in the pathogenesis of viral liver infections, especially in hepatitis C virus (HCV) infection. Regarding hepatitis B virus (HBV) infection, the data are limited, but important progress has been achieved in recent years. This review presents the latest advances pertaining to the role of the oxidative stress byproducts in the pathogenesis of chronic hepatitis B, constituting a source of potential new markers for the evaluation and monitoring of patients with chronic hepatitis B.

Chemotherapy induces plasmatic antioxidant changes in pediatric patients with acute lymphoid leukemia B that correlate to disease prognosis

Pediatric acute lymphoid leukemias (ALL) is the most common childhood cancer, and cytotoxic chemotherapy remains the primary treatment option. Chemotherapic drugs act by oxidative stress generation, but their clinical meaning is poorly understood. During the chemotherapy schedule, this study evaluated the antioxidant profile of peripheral blood samples from 34 patients diagnosed with type B-cell ALL (B-ALL). Peripheral blood samples were collected at diagnosis (D0) and during the induction, consolidation, and maintenance phases. The plasma total antioxidant capacity (TRAP) was determined using the high-sensitivity chemiluminescence technique. Antioxidant levels were higher on D0 compared to day 7 after treatment starting (D7) in the induction phase (28.68–1194.71 μM Trolox, p = 0.0178) and in the high-risk group (age > ten years and/or with white blood cell counts and/or > 50,000 white blood cells/m3 at diagnosis) concerning low-risk patients (253.79–1194.71 μM Trolox, p = 0.0314). Reduced TRAP was also detected in patients who died compared to those who survived (392.42–1194.71 μM Trolox, p = 0.0278). Patients under consolidation (56.14–352.05 μM Trolox, p=<0.0001) and maintenance (30.48–672.99 μM Trolox, p=<0.0001) showed a significant reduction in TRAP levels compared to those from the induction phase (28.68–1390.26 μM Trolox), reaching levels similar to cured patients out of treatment (64.82–437.82 μM Trolox). These findings suggest that the variation of the total antioxidant capacity in B-ALL during chemotherapy is a parameter that correlates to some predictors of disease prognosis.

•

ALL is the most common neoplasia in children.

•

Oxidative stress is reported in ALL patients, but the relationship between antioxidants and disease profile is unknown.

•

Changes in blood antioxidants during chemotherapy correlates to survival and risk stratification in childhood ALL.