The impact of SOX4-activated CTHRC1 transcriptional activity regulating DNA damage repair on cisplatin resistance in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is the predominant subtype within the spectrum of lung malignancies. CTHRC1 has a pro-oncogenic role in various cancers. Here, we observed the upregulation of CTHRC1 in LUAD, but its role in cisplatin resistance in LUAD remains unclear. Bioinformatics analysis was employed to detect CTHRC1 and SRY-related HMG-box 4 (SOX4) expression in LUAD. Gene Set Enrichment Analysis predicted the enriched pathways related to CTHRC1. JASPAR and MotifMap databases predicted upstream transcription factors of CTHRC1. Pearson analysis was conducted to analyze the correlation between genes of interest. The interaction and binding relationship between CTHRC1 and SOX4 were validated through dual-luciferase and chromatin immunoprecipitation assays. Quantitative real-time polymerase chain reaction determined the expression of CTHRC1 and SOX4 genes. CCK-8 was performed to assess cell viability and calculate IC50 value. Flow cytometry examined the cell cycle. Comet assay and western blot assessed DNA damage. CTHRC1 and SOX4 were upregulated in LUAD. CTHRC1 exhibited higher expression in cisplatin-resistant A549 cells compared to cisplatin-sensitive A549 cells. Knockdown of CTHRC1 enhanced DNA damage during cisplatin treatment and increased the sensitivity of LUAD cells to cisplatin. Additionally, SOX4 modulated DNA damage repair (DDR) by activating CTHRC1 transcriptional activity, promoting cisplatin resistance in LUAD cells. SOX4 regulated DDR by activating CTHRC1, thereby enhancing cisplatin resistance in LUAD cells. The finding provides a novel approach to address clinical cisplatin resistance in LUAD, with CTHRC1 possibly serving as a candidate for targeted therapies in addressing cisplatin resistance within LUAD.

Methionine redox regulation of actin-interacting proteins primarily governs antioxidative signaling and response to the salvianolic acid B treatment in EA.hy926 cells.

Actin-interacting proteins are important molecules for filament assembly and cytoskeletal signaling within vascular endothelium. Disruption in their interactions causes endothelial pathogenesis through redox imbalance. Actin filament redox regulation remains largely unexplored, in the context of pharmacological treatment. This work focused on the peptidyl methionine (M) redox regulation of actin-interacting proteins, aiming at elucidating its role on governing antioxidative signaling and response. Endothelial EA.hy926 cells were subjected to treatment with salvianolic acid B (Sal B) and tert-butyl-hydroperoxide (tBHP) stimulation. Mass spectrometry was employed to characterize redox status of proteins, including actin, myosin-9, kelch-like erythroid-derived cap-n-collar homology-associated protein 1 (Keap1), plastin-3, prelamin-A/C and vimentin. The protein redox landscape revealed distinct stoichiometric ratios or reaction site transitions mediated by M sulfoxide reductase and reactive oxygen species. In comparison with effects of tBHP stimulation, Sal B treatment prevented oxidation at actin M325, myosin-9 M1489/1565, Keap1 M120, plastin-3 M592, prelamin-A/C M187/371/540 and vimentin M344. For Keap1, reaction site was transitioned within its scaffolding region to the actin ring. These protein M oxidation regulations contributed to the Sal B cytoprotective effects on actin filament. Additionally, regarding the Keap1 homo-dimerization region, Sal B preventive roles against M120 oxidation acted as a primary signal driver to activate nuclear factor erythroid 2-related factor 2 (Nrf2). Transcriptional splicing of non-POU domain-containing octamer-binding protein was validated during the Sal B-mediated overexpression of NAD(P)H dehydrogenase [quinone] 1. This molecular redox regulation of actin-interacting proteins provided valuable insights into the phenolic structures of Sal B analogs, showing potential antioxidative effects on vascular endothelium.

Gossypol acetic acid regulates leukemia stem cells by degrading LRPPRC via inhibiting IL-6/JAK1/STAT3 signaling or resulting mitochondrial dysfunction.

BACKGROUND: Leukemia stem cells (LSCs) are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia (AML), as they are protected by the bone marrow microenvironment (BMM) against conventional therapies. Gossypol acetic acid (GAA), which is extracted from the seeds of cotton plants, exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2. AIM: To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism. METHODS: In this study, LSCs were magnetically sorted from AML cell lines and the CD34+CD38- population was obtained. The expression of leucine-rich pentatricopeptide repeat-containing protein (LRPPRC) and forkhead box M1 (FOXM1) was evaluated in LSCs, and the effects of GAA on malignancies and mitochondrial function were measured. RESULTS: LRPPRC was found to be upregulated, and GAA inhibited cell proliferation by degrading LRPPRC. GAA induced LRPPRC degradation and inhibited the activation of interleukin 6 (IL-6)/janus kinase (JAK) 1/signal transducer and activator of transcription (STAT) 3 signaling, enhancing chemosensitivity in LSCs against conventional chemotherapies, including L-Asparaginase, Dexamethasone, and cytarabine. GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC. Furthermore, GAA induced reactive oxygen species accumulation, disturbed mitochondrial homeostasis, and caused mitochondrial dysfunction. By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC, GAA resulted in the elimination of LSCs. Meanwhile, GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage. CONCLUSION: Taken together, the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML.

Primary pulmonary adenoid cystic carcinoma: A clinicopathological study of 64 patients.

BACKGROUND: This study aimed to investigate the clinicopathological features and prognostic indicators of primary pulmonary adenoid cystic carcinoma (PACC). METHODS: Clinical data were collected from 64 primary PACC patients and analyzed retrospectively at the Tianjin Medical University General Hospital, the West China Hospital of Sichuan University, the First Affiliated Hospital of Guangxi Medical University, and the Bishan Hospital of Chongqing Medical University from January 2003 to August 2023. The 64 patients (28 males and 36 females) were aged from 20 to 73 years, with a median age of 49 years and an average age of 49.3 years. RESULTS: Immunohistochemical staining showed that the tumors expressed CK7, S-100 protein, CK5/6, CD117, and p63. Seven patients underwent fluorescence in situ hybridization (FISH) testing and three were found to have myeloblastosis (MYB) gene translocation. In total, 53 patients underwent surgery, among whom 31 received only surgery and 22 received both surgery and postoperative chemoradiotherapy. In addition, 10 patients received chemoradiotherapy only, while one patient underwent treatment with traditional Chinese medicine. The overall survival rates in the first, third, and fifth years were 98.4%, 95.3%, and 87.5%, respectively. CONCLUSION: Prognostic analysis revealed that age, tumor size, lymph node metastasis status, margin status, and choice of treatment modality significantly influenced the patients' prognosis.

Low­dose venetoclax combined with azacitidine in older and frail patients with newly diagnosed acute myeloid leukaemia.

In the present study, the aim was to evaluate the clinical efficacy and safety of low-dose venetoclax combined with azacitidine for the treatment of older and frail patients with newly diagnosed acute myeloid leukaemia (AML). Data of 26 older patients with newly diagnosed AML admitted to Yuyao People's Hospital (Yuyao, China) between January 2021 and May 2023 were retrospectively analysed. The treatment regimens were as follows: Subcutaneous injection of 100 mg azacitidine on days 1-5 and 100 mg oral venetoclax on days 3-16 or 200 mg oral venetoclax on days 3-30. The median age of the 26 patients was 73 years. After the first course of treatment, the complete remission (CR) and CR with incomplete haematological recovery rate was 84.6%, and the objective response rate was 96.2%. The most common adverse events noted during treatment were haematological adverse events including grade 3/4 granulocytosis (57.7%), febrile neutropenia (30.8%), pulmonary infection (32.0%), thrombocytopenia (42.3%) and anaemia (42.3%). A total of 13 (50.0%) patients did not require platelet (PLT) infusion during treatment. The main non-haematological adverse reactions included gastrointestinal reactions such as nausea, vomiting and diarrhoea. Patients were followed up until December 2023, with a median follow-up time of 9.5 months (range, 1.9-26.0 months). Of the 26 patients, nine (34.6%) patients experienced relapse, with a mean recurrence time of 5.9 months. In conclusion, preliminary results indicated that low-dose venetoclax combined with azacitidine is effective and safe for the treatment of older and frail patients with newly diagnosed AML, providing a new treatment option for these patients.