Reversal of Multidrug Resistance by Apolipoprotein A1-Modified Doxorubicin Liposome for Breast Cancer Treatment.

Multidrug resistance (MDR) remains a major problem in cancer therapy and is characterized by the overexpression of p-glycoprotein (P-gp) efflux pump, upregulation of anti-apoptotic proteins or downregulation of pro-apoptotic proteins. In this study, an Apolipoprotein A1 (ApoA1)-modified cationic liposome containing a synthetic cationic lipid and cholesterol was developed for the delivery of a small-molecule chemotherapeutic drug, doxorubicin (Dox) to treat MDR tumor. The liposome-modified by ApoA1 was found to promote drug uptake and elicit better therapeutic effects than free Dox and liposome in MCF-7/ADR cells. Further, loading Dox into the present ApoA1-liposome systems enabled a burst release at the tumor location, resulting in enhanced anti-tumor effects and reduced off-target effects. More importantly, ApoA1-lip/Dox caused fewer adverse effects on cardiac function and other organs in 4T1 subcutaneous xenograft models. These features indicate that the designed liposomes represent a promising strategy for the reversal of MDR in cancer treatment.

Age-Related Differences in Vancomycin-Associated Nephrotoxicity and Efficacy in Methicillin-Resistant Staphylococcus aureus Infection: A Comparative Study between Elderly and Adult Patients.

Elderly patients (age ≥ 65 years) are susceptible to methicillin-resistant Staphylococcus aureus (MRSA) infections, with potential for more adverse treatment outcomes or complications compared to younger adults (18-64 years). This study compared vancomycin-associated nephrotoxicity and efficacy in elderly and adult patients and investigated the correlation between vancomycin pharmacokinetic/pharmacodynamic (PK/PD) indices and clinical outcomes. A prospective study was conducted in 10 hospitals in Shanghai from October 2012 to November 2019. A total of 164 patients with MRSA infections were enrolled, including 83 elderly and 81 adult patients. Vancomycin therapeutic drug monitoring (TDM) was performed in all patients, indicating significantly higher vancomycin trough concentrations (Ctrough), 24-h area under the curve (AUC24) values, and AUC24/minimum inhibitory concentration (AUC24/MIC) values in elderly patients compared to adult patients. The incidence of vancomycin-associated nephrotoxicity was nearly three times higher in elderly patients (18.1% vs. 6.2%, p = 0.020), despite similar clinical and microbiological efficacy. Of particular importance, a Ctrough > 20 mg/L was found as an independent factor of nephrotoxicity in elderly patients. Further analysis of patients with an estimated glomerular filtration rate (eGFR) > 60 mL/min/1.73 m2 also revealed that elderly patients had significantly higher vancomycin-related PK/PD indices and more nephrotoxicity than adult patients. In conclusion, elderly patients receiving vancomycin therapy face a higher risk of nephrotoxicity, which requires close vancomycin TDM, especially when the Ctrough exceeds 20 mg/L.

Pharmacokinetics and safety of mavacamten in healthy Chinese participants with different CYP2C19 phenotypes.

Obstructive hypertrophic cardiomyopathy (oHCM) is a subtype of HCM characterized by left ventricular outflow tract obstruction resulting from cardiac muscle hypertrophy and anatomic alterations in the mitral valve and apparatus. Mavacamten, a cardiac myosin inhibitor metabolized primarily by CYP2C19 in the liver, is the first and only targeted medication approved for the treatment of symptomatic New York Heart Association (NYHA) class II-III oHCM. Previous pharmacokinetic (PK) results of mavacamten in healthy Caucasian, Japanese, and Asian participants demonstrated that mavacamten exposure was affected by CYP2C19 metabolism status. This open-label, parallel-group, phase I trial aimed to determine the PK and safety of mavacamten in healthy Chinese participants with different CYP2C19 genotypes. The primary outcome was to define the PK of mavacamten in healthy Chinese participants; the secondary outcome was to examine safety and tolerability. After a single oral dose of 15 or 25 mg mavacamten in fasted healthy adult Chinese individuals, Cmax was reached within a median Tmax of 0.6-1.5 h, indicating rapid absorption. Inter-individual variability was moderate, and individuals carrying non-functional CYP2C19 alleles (*2/*2, *3/*3, or *2/*3) exhibited longer half-life and increased total exposure. After stratification of CYP2C19 genotypes, total mavacamten exposures were similar among different ethnic groups when compared with prior PK studies. No significant adverse events were observed in this study. Single oral administration of mavacamten at 15 mg was well tolerated across all CYP2C19 genotypes, and 25 mg dose was well tolerated in healthy participants with CYP2C19 genotypes UM/RM/NM. The PK profile of mavacamten in the healthy Chinese population was consistent with that in other healthy populations.

Enhanced chemoimmunotherapy of breast cancer in mice by apolipoprotein A1-modified doxorubicin liposomes combined with interleukin-21.

Backgroud: Breast cancer is a prevalent malignancy among women, with triple-negative breast cancer (TNBC) comprising approximately 15-20% of all cases, possessing high invasiveness, drug resistance and poor prognosis. Chemotherapy, the main treatment for TNBC, is limited by toxicity and drug resistance. Apolipoprotein A1 modified doxorubicin liposome (ApoA1-lip/Dox) was constructed in our previous study, with promising anti-tumour effect and improved safety been proved. However, during long-term administration, the problem of cumulative toxicity and insufficient tumour inhibition is still inevitable. Interleukin-21 is a small molecule protein secreted by T cells with various immune regulatory functions. IL-21 has significantly curative effects in numerous solid tumours, but it has the disadvantages of low response rate and short half-life. The combination of chemotherapy and immunotherapy has received increasing attention.Purpose: In this study, ApoA1 drug loading system and long-acting IL-21 are innovatively combined for tumour treatment.Methods: We combined ApoA1-lip/Dox and IL-21 for treatment and evaluated their impact on tumor-infiltrating lymphocytes and CD8+ T and NK cell cytotoxicity.Results: Combined administration significantly improved the tumour-infiltrating lymphocytes and enhanced the cytotoxicity of CD8+ T and NK cells. The combination of ApoA1-lip/Dox and IL-21 exhibits significantly enhanced anti-tumour efficacy with lower toxicity of ApoA1-lip/Dox, providing a new strategy for TNBC treatment with enhanced anti-tumour response and reduced toxicity.

Nemonoxacin Has Immunoprotective Effects on Reducing Mortality in Lipopolysaccharide-Induced Mouse Sepsis Model.

Nemonoxacin is a novel non-fluorinated quinolone. The effect of nemonoxacin on modulation of host immune response is not known. We sought to determine whether nemonoxacin has immunoprotective effects on lipopolysaccharide (LPS)-induced mouse sepsis model. Therefore, mice were challenged with lethal dose LPS (12.5 mg/kg) only or LPS with multi-dose nemonoxacin (40 mg/kg q12h) by intraperitoneal injection, and the results showed nemonoxacin could significantly reduce mortality from 80 to 30% in this model. The effect of nemonoxacin on immune cells in vivo and in vitro was also investigated. Mice were treated with sublethal LPS (5 mg/kg) or LPS + nemonoxacin, the myeloid cell subsets in mouse spleen were analyzed by flow cytometry, and cytokines in mouse serum were measured by ELISA. Additionally, mouse macrophage RAW264.7 cells were treated with LPS or LPS + nemonoxacin to investigate the immune modulatory effect of nemonoxacin in vitro, and the level of cytokines in cell culture supernatant was determined by ELISA. Analysis of myeloid cell subsets in the spleen showed nemonoxacin pretreatment could significantly inhibit LPS-induced proliferation of macrophages and dendritic cells but have no effect on neutrophils. Nemonoxacin could significantly reduce the expression of pro-inflammatory cytokines IL-6 and TNF-α while increase anti-inflammatory cytokine IL-10 expression, which were induced by LPS in vivo and in vitro. Finally, the immunomodulation of nemonoxacin in macrophage phagocytosis was also examined. The results displayed nemonoxacin pretreatment could significantly enhance the phagocytic function of macrophage. In conclusion, nemonoxacin has immune modulatory and protective effect on LPS-induced inflammation in vivo and in vitro.