OBJECTIVE To study the mitochondrial toxicity effect of Radix Aconiti Lateralis Praepa?rata(Fuzi)on H9c2 cardiomyocytes. METHODS H9c2 cells were exposed to Fuzi decoction 6.25, 12.5,25,50 and 100 g·L-1 for 24 h. Fluorescence staining and CCK-8 assay were used to detect cell viability. H9c2 cells were exposed to Fuzi decoction 6.25,12.5 and 25 g · L-1 for 24 h,while the effect on mitochondrial membrane potential and reactive oxygen species(ROS)was detected by flow cytometry. The fluorescence molecular probe and laser scanning confocal microscope were used to observe the effect on Ca2+ in cells,Ca2+ and superoxide in mitochondria. The effect on ATP concentration in cells was detected via firefly luciferin and the expression of Pgc-1α,Bcl-2 and Bax mRNA evaluated by real-time PCR,while the expression of Pgc-1α protein was measured by Western blotting. RESULTS H9c2 cell viability was significantly inhibited by Fuzi decoction 12.5-100 g · L-1(P<0.05,P<0.01). The IC50 value was 47.4669 g · L-1,while the 95%confidence limit was 32.5997-69.1145 g · L-1. After treatment with Fuzi decoction 25 g · L-1 ,the fluorescence intensity of ROS in the normal control group increased from 204±67 to 454±78(P<0.05),that of mitochondrial superoxide increased from 5.4±1.8 to 26.8±8.5 (P<0.01),mitochondrial membrane potential decreased from 1.7±0.5 to 0.8±0.4(P<0.05),the fluores?cence intensity of intracellular Ca2+increased from 7.8±0.8 to 22.1±0.5(P<0.05)while that of mitochon?drial Ca2+decreased from 38.0±4.3 to 9.2±1.6(P<0.01),and intracellular ATP concentration decreased from (10.6 ± 0.4)μmol · g-1 to (5.3 ± 1.1)μmol · g-1 protein (P<0.05). qPCR and Western blotting test results showed that compared with the normal control group ,Pgc-1αand Bcl-2 mRNA relative expression level in Fuzi decoction 25 g·L-1 group was decreased from 1.00±0.10 and 1.00±0.10 to 0.09±0.06(P<0.01)and 0.43±0.06(P<0.01),respectively, while the relative expression of Bax mRNA was increased from 1.00 ± 0.03 to 1.17 ± 0.06 (P<0.05),and the expression of Pgc-1α protein was decreased from 0.906±0.034 to 0.541±0.003(P<0.01). CONCLUSION Fuzi has some mitochondrial toxicity to cardiomy?opathy. This effect arises from the combined action of different mechanisms. Mitochondrial toxicity of myocytes may account for the cardiac toxicity of Fuzi.

OBJECTIVE: Immunotherapy has brought significant clinical benefits to a subset of patients, but has thus far been disappointing in the treatment of immunologically "cold" tumors. Existing biomarkers that can precisely identify these populations are insufficient. In this context, a potential cold tumor microenvironment (TME) marker FARSB was investigated to reveal its impact on TME and patients' response to immunotherapy across pan-cancer. METHODS: The expression levels and mutational landscape of FARSB in pan-cancer were investigated. Kaplan-Meier and univariate Cox regression analyses were applied to analyze the prognostic significance of FARSB. Pathways affected by FARSB were investigated by gene set enrichment and variation analysis. The relationship between FARSB expression and immune infiltration was examined using the TIMER2 and R packages. Single-cell RNA sequencing (scRNA-seq) data of several cancer types from GSE72056, GSE131907, GSE132465, GSE125449 and PMID32561858 were analyzed to validate the impact of FARSB on the TME. The predictive effect of FARSB on immunotherapy efficacy was explored in 3 immune checkpoint inhibitors (ICIs)- treated cohorts (PMID32472114, GSE176307, and Riaz2017). RESULTS: FARSB expression was significantly higher in 25 tumor tissues than in normal tissues and was associated with poor prognosis in almost all tumor types. FARSB expression exhibited a strong association with several DNA damage repair pathways and was significantly associated with TP53 mutation in lung adenocarcinoma (P < 0.0001, OR=2.25). FARSB characterized a typical immune desert TME and correlated with impaired expression of chemokines and chemokines receptors. Large-scale scRNA-seq analysis confirmed the immunosuppressive role of FARSB and revealed that FARSB potentially shapes the cold TME by impeding intercellular interactions. In 3 ICI-treated cohorts, FARSB demonstrated predictive value for immunotherapy. CONCLUSION This study provides a pan-cancer landscape of the FARSB gene by integrated single-cell and bulk DNA sequencing analysis and elucidates its biological function to promote DNA damage repair and construct the immune desert TME, suggesting the potential value of FARSB as a novel marker for stratifying patients with poor immunotherapeutic benefits and "cold" TME.
Humans ; Tumor Microenvironment ; Prognosis ; Adenocarcinoma of Lung/genetics* ; Lung Neoplasms/genetics* ; Sequence Analysis, RNA