Short-Term Changes in Peak VO2 After Initiation of Dapagliflozin in Heart Failure Across Iron Status.

BACKGROUND: Some studies have indicated that sodium-glucose cotransporter-2 (SGLT2) inhibitors promote an increase in cell iron use. OBJECTIVES: The aim of this study was to examine, in patients with stable heart failure with reduced left ventricular ejection fraction (HFrEF), the effect of dapagliflozin on ferrokinetic parameters and whether short-term changes in peak oxygen consumption (Vo2) after dapagliflozin treatment are influenced by baseline and serial ferrokinetic status. METHODS: This was an exploratory analysis of a randomized, double-blind clinical trial that evaluated the effect of dapagliflozin vs placebo on peak Vo2 in patients with HFrEF (NCT04197635) and included 76 of the 90 patients initially enrolled in the trial. Changes in peak Vo2 at 1 and 3 months were explored according to baseline and longitudinal ferrokinetic parameters (natural logarithm [ln] ferritin, transferrin saturation index [TSAT], soluble transferrin receptor, and hepcidin). Linear mixed-effect regression was used for the analyses. RESULTS: Compared with placebo, dapagliflozin led to a significant decrease in 3-month ln ferritin (P = 0.040) and an increase in 1-month ln soluble transferrin receptor (P = 0.023). Between-treatment comparisons revealed a stepwise increase in peak Vo2 in the dapagliflozin group at 1 and 3 months, which was especially apparent at lower baseline values of TSAT and ferritin (P < 0.05). Lower time-varying values of TSAT (1 and 3 months) also identified patients with greater improvements in peak Vo2. CONCLUSIONS: In patients with stable HFrEF, treatment with dapagliflozin resulted in short-term increases in peak Vo2, which were most marked in patients with surrogates of greater iron deficiency at baseline and during treatment. (Short-Term Effects of Dapagliflozin on Peak Vo2 in HFrEF [DAPA-VO2]; NCT04197635).

Artesunate, a new antimalarial clinical drug, exhibits potent anti-AML activity by targeting the ROS/Bim and TFRC/Fe2+ pathways.

BACKGROUND AND PURPOSE: Artesunate, approved by the Food and Drug Administration in 2020 as a new treatment for severe malaria, also shows anti-tumour activity against acute myeloid leukaemia (AML). However, the underlying molecular mechanism(s) of artesunate-induced apoptosis and differentiation of AML is not clearly elucidated. EXPERIMENTAL APPROACH: The biological effects of artesunate on AML were explored in vitro, using cells from AML patients and leukaemia cell lines, and in vivo, using female C57BL/6 or nude nu/nu BALB/c mice. Underlying mechanisms in vitro were examined with the Trypan blue dye exclusion assay, western blotting and flow cytometry. Effects of artesunate in C57BL/6 mice intravenously injected with murine AML cells (C1498-GFP) were assessed by numbers of AML cells and by survival. KEY RESULTS: In vitro, artesunate promoted apoptosis and differentiation in both leukaemia cell lines and patient-derived primary leukaemia cells. Mechanistically, artesunate promoted cell apoptosis by triggering reactive oxygen species (ROS) production and increasing expression of the pro-apoptotic protein Bim. Interestingly, transferrin receptor 1 (TFRC)-mediated regulation of intracellular iron homeostasis also played an essential role in AML cell differentiation induced by artesunate. In vivo, artesunate slowed AML progression and prolonged survival in a mouse leukaemia model. Notably, artesunate displayed no apparent toxicity towards healthy haematopoietic stem cells, bone marrow mononuclear cells or experimental animals. CONCLUSION AND IMPLICATIONS: Artesunate is a safe agent with significant anti-leukaemia effects in mice and may serve as a promising chemotherapeutic strategy for patients with AML, based on two different mechanisms, targeting the ROS/Bim and the TFRC/Fe2+ pathways.

PDT-active upconversion nanoheaters for targeted imaging guided combinatorial cancer phototherapies with low-power single NIR excitation.

A versatile nanoformulation is designed by anchoring human transferrin protein (Tf) on fluoromagnetic upconverting nanoheaters, NaGdF4:Yb,Er (UCNP), loaded with Rose Bengal (RB), for multimodal imaging guided synergistic photothermal (PTT) and photodynamic therapy (PDT) at the targeted tumor site. The NIR excitation of the UCNP-RB Forster Resonance Energy Transfer (FRET) pair results in the reactive oxygen species (ROS) generation for PDT, whereas the non-radiative transitions in Er result in the heat required for PTT. The intravenously injected theranostic agent (UCNP@Tf-RB) enabled; (1) combinatorial PTT and PDT of 4T1 tumors with minimal systemic toxicity, (2) dual targeted (passive and active) tumor accumulation, (3) dual-modal imaging (MRI/photothermal), and, (4) excellent stability and biocompatibility. The in vitro therapy data corroborates the MRI findings that Tf conjugation resulted in actively targeted tumor accumulation via over-expressed transferrin receptors (TfR) on 4T1 cells. Real-time photothermal imaging enabled visualization of the tumor while receiving the therapy. The UCNP@Tf-RB, for synergistic PTT-PDT, and UCNP@Tf, for PTT only, caused rapid suppression of tumor with a tumor-growth inhibition index (TGII) of ~0.91, and 0.79, respectively. Histopathological examination demonstrated minimal damage to non-targeted tissues and caused significant damage to the tumor. This theranostic methodology enhances anti-cancer therapeutic efficiency, and announces the potential for pre-clinical cancer therapy.

A Brain-Targeting Bispecific-Multivalent Antibody Clears Soluble Amyloid-Beta Aggregates in Alzheimer's Disease Mice.

Amyloid-ß (Aß) oligomers and protofibrils are suggested to be the most neurotoxic Aß species in Alzheimer's disease (AD). Hence, antibodies with strong and selective binding to these soluble Aß aggregates are of therapeutic potential. We have recently introduced HexaRmAb158, a multivalent antibody with additional Aß-binding sites in the form of single-chain fragment variables (scFv) on the N-terminal ends of Aß protofibril selective antibody (RmAb158). Due to the additional binding sites and the short distance between them, HexaRmAb158 displayed a slow dissociation from protofibrils and strong binding to oligomers in vitro. In the current study, we aimed at investigating the therapeutic potential of this antibody format in vivo using mouse models of AD. To enhance BBB delivery, the transferrin receptor (TfR) binding moiety (scFv8D3) was added, forming the bispecific-multivalent antibody (HexaRmAb158-scFv8D3). The new antibody displayed a weaker TfR binding compared to the previously developed RmAb158-scFv8D3 and was less efficiently transcytosed in a cell-based BBB model. HexaRmAb158 detected soluble Aß aggregates derived from brains of tg-ArcSwe and AppNL-G-F mice more efficiently compared to RmAb158. When intravenously injected, HexaRmAb158-scFv8D3 was actively transported over the BBB into the brain in vivo. Brain uptake was marginally lower than that of RmAb158-scFv8D3, but significantly higher than observed for conventional IgG antibodies. Both antibody formats displayed similar brain retention (72 h post injection) and equal capacity in clearing soluble Aß aggregates in tg-ArcSwe mice. In conclusion, we demonstrate a bispecific-multivalent antibody format capable of passing the BBB and targeting a wide-range of sizes of soluble Aß aggregates.

Hypoxia-inducible factor prolyl hydroxylase inhibitors for anaemia in maintenance dialysis: a meta-analysis.

BACKGROUND: Anaemia is a common complication of end-stage renal disease (ESRD) that relies on dialysis. Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHI) is a new class of small-molecule oral drugs for the treatment of anaemia in chronic kidney disease. They demonstrate several advantages over traditional exogenous erythropoietin (EPO). We conducted a meta-analysis of studies that compared the efficacy of HIF-PHI in erythropoiesis and iron metabolism, and its safety with EPO in maintenance dialysis patients. METHODS: A sensitive search strategy in the PubMed, EMBASE and Cochrane databases identified all citations for randomised controlled trials (RCTs) comparing HIF-PHI agents with EPO/placebo through December 2021. RESULTS: Fourteen RCTs were identified, which included 2738 patients. No statistical difference was found in haemoglobin increase (p = 0.37) between HIF-PHI treatment and EPO using the random-effects model. HIF-PHI administration upregulated transferrin (MD 36.12, 95% CI 27.04-45.20) and soluble transferrin receptors (sTfR) (MD 1.28, 95% CI 0.44-2.13), but did not statistically reduce hepcidin level (p = 0.37). Total and LDL-cholestrol levels were suppressed by HIF-PHI (MD - 0.99, 95% CI - 1.34 to - 0.63) (MD - 0.99, 95% CI - 1.34 to - 0.64), while triglyceride (TG) was not different between HIF-PHI and EPO (p = 0.74). The total incident rates of treatment-emergent adverse events (TEAE) (p = 0.20) from HIF-PHI treatment were not different from those of erythropoietin, while the treatment-emergent serious adverse events (TSAE) (p = 0.02) were higher in the HIF-PHI group than those in the EPO controls with the fixed-effect model. CONCLUSION: HIF-PHI could effectively upregulate and maintain haemoglobin levels in patients with anaemia receiving maintenance dialysis. Furthermore, HIF-PHI could elevate iron metabolism activity and utility without inducing treatment-associated serious adverse events. Robust data from larger RCTs with longer treatment duration and follow-up are needed.

[Reassessing the six months prognosis of patients with severe or very severe aplastic anemia without hematological responses at three months after immunosuppressive therapy].

Objective: To reassess the predictors for response at 6 months in patients with severe or very severe aplastic anemia (SAA/VSAA) who failed to respond to immunosuppressive therapy (IST) at 3 months. Methods: We retrospectively analyzed the clinical data of 173 patients with SAA/VSAA from 2017 to 2018 who received IST and were classified as nonresponders at 3 months. Univariate and multivariate logistic regression analysis were used to evaluate factors that could predict the response at 6 months. Results: Univariate analysis showed that the 3-month hemoglobin (HGB) level (P=0.017) , platelet (PLT) level (P=0.005) , absolute reticulocyte count (ARC) (P<0.001) , trough cyclosporine concentration (CsA-C0) (P=0.042) , soluble transferrin receptor (sTfR) level (P=0.003) , improved value of reticulocyte count (ARC(△)) (P<0.001) , and improved value of soluble transferrin receptor (sTfR(△)) level (P<0.001) were related to the 6-month response. The results of the multivariate analysis showed that the PLT level (P=0.020) and ARC(△) (P<0.001) were independent prognostic factors for response at 6 months. If the ARC(△) was less than 6.9×10(9)/L, the 6-month hematological response rate was low, regardless of the patient's PLT count. Survival analysis showed that both the 3-year overall survival (OS) [ (80.1±3.9) % vs (97.6±2.6) %, P=0.002] and 3-year event-free survival (EFS) [ (31.4±4.5) % vs (86.5±5.3) %, P<0.001] of the nonresponders at 6 months were significantly lower than those of the response group. Conclusion: Residual hematopoietic indicators at 3 months after IST are prognostic parameters. The improved value of the reticulocyte count could reflect whether the bone marrow hematopoiesis is recovering and the degree of recovery. A second treatment could be performed sooner for patients with a very low ARC(△).

Modelling of mass transport and distribution of aptamer in blood-brain barrier for tumour therapy and cancer treatment.

The blood-brain barrier (BBB) is a strong barrier against the entrance of drugs, which has made brain cancer treatment a major challenge. We have previously shown that targeting transferrin receptors using aptamers increased brain drug delivery. To get a better understanding of this phenomenon, in the present article, a mathematical model based on the finite element method was developed accounting for the fluid flow and mass transport of the aptamer molecule inside an 8 µm capillary vessel across a 14 µm blood-brain barrier domain. The fluid flow and mass transport equations were coupled to calculate the blood velocity and aptamer concentration profiles across the BBB. It was identified that the thickness of the astrocyte and endothelial cell layers are key parameters affecting the concentration of the aptamer delivered to the last neuron dendrites in the BBB. The predicted efficacy of the drug delivery (Capt/Cin) of 10.9% to 13.8% was calculated at a porosity of 0.5 to 0.9, respectively, at a blood velocity of 0.38 mm/s, which was independent of the inlet concentration of the aptamer. This low efficacy was attributed to the mass transfer resistance across endothelial cells, astrocyte and pericyte layers, which decreased the concentration by 6.7%. It was also identified that the main mechanism of drug delivery is switched from convective mass transport in the capillary layer (with Peclet number > 50) to mixed convection mass transport (1 < Peclet number < 5) in the porous layers and to diffusion only once aptamer reached the brain parenchyma (Peclet number < 1).

Sinapine induced ferroptosis in non-small cell lung cancer cells by upregulating transferrin/transferrin receptor and downregulating SLC7A11.

Sinapine (SI) is a naturally occurring product with biological properties, but its activity against non-small cell lung cancer (NSCLC) remains unclear. This research examined the anti-tumour effects of SI in NSCLC cells and the underlying mechanisms of any effects. SI induced ferroptosis, a novel form of cell death, by increasing intracellular ferrous iron, lipid peroxidation, and reactive oxygen species (ROS) in NSCLC cells. SI treatment resulted in transferrin and transferrin receptor upregulation, and inhibition of transferrin or the transferrin receptor reduced the ferroptosis caused by SI. SI treatment also resulted in a p-53 dependent downregulation of SLC7A11. Finally, we evaluated the effects of SI in vivo and it was found that SI also successfully inhibited the growth of NSCLC in vivo. In summary, our data demonstrated that SI triggered ferroptosis in NSCLC cells and may be a promising therapeutic agent for this condition.

Reassessing the six months prognosis of patients with severe or very severe aplastic anemia without hematological responses at three months after immunosuppressive therapy / 中华血液学杂志

Objective: To reassess the predictors for response at 6 months in patients with severe or very severe aplastic anemia (SAA/VSAA) who failed to respond to immunosuppressive therapy (IST) at 3 months. Methods: We retrospectively analyzed the clinical data of 173 patients with SAA/VSAA from 2017 to 2018 who received IST and were classified as nonresponders at 3 months. Univariate and multivariate logistic regression analysis were used to evaluate factors that could predict the response at 6 months. Results: Univariate analysis showed that the 3-month hemoglobin (HGB) level (P=0.017) , platelet (PLT) level (P=0.005) , absolute reticulocyte count (ARC) (P<0.001) , trough cyclosporine concentration (CsA-C0) (P=0.042) , soluble transferrin receptor (sTfR) level (P=0.003) , improved value of reticulocyte count (ARC(△)) (P<0.001) , and improved value of soluble transferrin receptor (sTfR(△)) level (P<0.001) were related to the 6-month response. The results of the multivariate analysis showed that the PLT level (P=0.020) and ARC(△) (P<0.001) were independent prognostic factors for response at 6 months. If the ARC(△) was less than 6.9×10(9)/L, the 6-month hematological response rate was low, regardless of the patient's PLT count. Survival analysis showed that both the 3-year overall survival (OS) [ (80.1±3.9) % vs (97.6±2.6) %, P=0.002] and 3-year event-free survival (EFS) [ (31.4±4.5) % vs (86.5±5.3) %, P<0.001] of the nonresponders at 6 months were significantly lower than those of the response group. Conclusion: Residual hematopoietic indicators at 3 months after IST are prognostic parameters. The improved value of the reticulocyte count could reflect whether the bone marrow hematopoiesis is recovering and the degree of recovery. A second treatment could be performed sooner for patients with a very low ARC(△).

Iron deficiency in patients with solid tumours: prevalence and management in clinical practice

PURPOSE: The objective of the present study was to describe the prevalence and management of anaemia and iron deficiency (ID) in treatment-naïve patients with solid tumours in Spain and the incidence of anaemia over 4 months of cancer treatment in clinical practice. METHODS: Multicentre, prospective and observational study in newly diagnosed cancer patients. Data on anaemia and iron parameters and its management were collected prior to the initiation of chemotherapy, at each cycle of chemotherapy and after 4 months of treatment. The main outcomes of the study were the prevalence of anaemia at baseline, its incidence during cancer treatment and the prevalence of absolute ID (AID) and functional ID (FID) prior to chemotherapy initiation. RESULTS: A total of 295 patients were included in the study. Anaemia was present at diagnosis in 38.6 % of patients and was treated only in 32.5 % of those. A total of 106 patients (60.2 %) without anaemia at baseline developed anaemia during cancer treatment. Serum ferritin and transferrin saturation data were available for 151 of the patients (51.2 %) included in the study. The overall prevalence of ID was 59 %: 48 patients (31.8 %) presented with AID and 41 patients (27.2 %) presented with FID before starting anti-cancer therapy. Thirty-three of 44 non-anaemic iron-deficient patients did not receive any type of iron supplementation before initiating cancer therapy. CONCLUSIONS: Iron parameters are not commonly measured in newly diagnosed cancer patients. A correct evaluation and early management of ID could reduce the incidence of treatment-related anaemia in cancer patients (AU)

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[Predicting early response to immunosuppressive therapy in severe aplastic anemia by soluble transferrin receptor assay].

OBJECTIVE: To evaluate the value of serum soluble transferrin receptor (sTfR) concentration in predicting early response to immunosuppressive therapy (IST) in severe aplastic anemia (SAA). METHODS: Clinical data and hematologic responses of 140 SAA patients treated with rabbit antithymocyte globulin (rATG) combination with cyclosporine in our hospital were retrospectively analyzed. Correlation of pre-IST baseline of sTfR and IST responses was statistically analyzed and receiver operating characteristic (ROC) curve was used to estimate the sensitivity and specificity of sTfR in prediction of early responses. RESULTS: Serum concentration of sTfR in very SAA (VSAA) patients were significantly lower than SAA and transfusion dependent non-SAA cases (P=0.001). The responders, especially at 3 months, had significantly higher pre- IST baseline of sTfR [median, 0.89 (range, 0.21-2.42) mg/L] than that [median, 0.58 (range, 0.13-1.88) mg/L] of non-responders (P=0.005). The cutoff level of 0.91 mg/L and 0.88 mg/L for predicting responses at 3 and 6 months were established based on the ROC curve, with the degree of accuracy of 65.0% and 60.7% respectively. Multivariate analysis showed that pre-IST baseline of sTfR was the independent factor of predicting response at 3 months (P=0.007) and at 6 months (P=0.021). CONCLUSION: As a indicator of bone marrow failure severity, sTfR could predict early response to IST therapy in aplastic anemia.

[Research advance on transferrin receptor in hematological malignant tumor treatment].

Iron is one of the necessary elements for cell growth, proliferation and functional activities. Iron uptake of the vast majority cells, including tumor cells, is primarily mediated by transferrin receptor (TfR). Studies showed that transferrin receptor expressed on tumor cell surface at a high level, thus can be used in the treatment for malignant tumor combined with many kinds of materials. In this article, recent progress of study on transferrin receptor used in treating hematological malignant tumor are reviewed from aspects of transferrin receptor combined with drugs including artemisinin, doxorubicin, gambogic acid and so on, genes, antibodies, polyethylene glycol and nanoparticles.

Potent and specific killing of human malignant brain tumor cells by an anti-transferrin receptor antibody-ricin immunotoxin.

Immunotoxins are hybrid molecules which combine the exquisite selectivity of monoclonal antibodies with the potent toxicity of protein toxins. An immunotoxin was constructed by linking a murine monoclonal antibody against the human transferrin receptor (TR) to the plant toxin, ricin. The cytotoxic activity of the anti-TR-ricin immunotoxin was tested in vitro and demonstrated highly potent and cell type-specific killing of cells derived from human glioblastoma, medulloblastoma, and leukemia. The anti-TR-ricin immunotoxin killed more than 50% of "target" cells at a concentration of 5.6 X 10(-13) M after an 18-hour incubation with the ionophore, monensin. This potency exceeds that of any other anti-TR immunotoxin reported in the literature. When the activity of the anti-TR-ricin immunotoxin against "target" tumor-derived cells was compared with the immunotoxin's activity against "non-target" cells, it could be predicted that a selective toxicity of anti-TR-ricin immunotoxin between tumor cells and normal brain was more than 150- to 1380-fold. Solid-phase indirect radioimmunoassay techniques were used to demonstrate significantly higher levels of TR in the glioblastoma- and medulloblastoma-derived cell lines, as well as in surgical tissue samples of medulloblastoma and glioblastoma, as compared to normal brain. Immunotoxins targeted to the TR may possess sufficient specificity to be of therapeutic importance, particularly to treat neoplastic disease of the central nervous system involving compartments (such as intrathecal, intraventricular, or cystic) where delivery of immunotoxins to tumor would not require transvascular transport.