Characterization of cotinine degradation in a newly isolated Gram-negative strain Pseudomonas sp. JH-2.

Cotinine, the primary metabolite of nicotine in the human body, is an emerging pollutant in aquatic environments. It causes environmental problems and is harmful to the health of humans and other mammals; however, the mechanisms of its biodegradation have been elucidated incompletely. In this study, a novel Gram-negative strain that could degrade and utilize cotinine as a sole carbon source was isolated from municipal wastewater samples, and its cotinine degradation characteristics and kinetics were determined. Pseudomonas sp. JH-2 was able to degrade 100 mg/L (0.56 mM) of cotinine with high efficiency within 5 days at 30 ℃, pH 7.0, and 1% NaCl. Two intermediates, 6-hydroxycotinine and 6-hydroxy-3-succinoylpyridine (HSP), were identified by high-performance liquid chromatography and liquid chromatograph mass spectrometer. The draft whole genome sequence of strain JH-2 was obtained and analyzed to determine genomic structure and function. No homologs of proteins predicted in Nocardioides sp. JQ2195 and reported in nicotine degradation Pyrrolidine pathway were found in strain JH-2, suggesting new enzymes that responsible for cotinine catabolism. These findings provide meaningful insights into the biodegradation of cotinine by Gram-negative bacteria.

Circular RNA SMARCA5 Promotes a Poor Prognosis and Radiotherapy Resistance for Patients with Hepatocellular Carcinoma.

OBJECTIVE: The involvement of Circular RNA SMARCA5 (cSMARCA5) in several types of cancer has been reported; however, its role in hepatocellular carcinoma (HCC) is unclear. The presented research aimed to explore the expression level of cSMARCA5 in HCC tissues and evaluate the association between cSMARCA5, prognosis, and radiotherapy resistance for patients with HCC. METHODS: This study was designed as a case controlled study and enrolled 106 HCC patients. HCC and paired non-tumor samples were collected from HCC patients. Gene expression was analyzed by RT-qPCR. The association between the expression level of cSMARCA5 and prognosis value and radiotherapy resistance for patients with HCC was analyzed by Kaplan-Meier survival curve and Multivariate Cox analysis. RESULTS: Compared to paracancerous tissue, cSMARCA5 demonstrated higher expression in the tumor tissues (p<0.0001).Higher expression of cSMARCA5 is a risk factor in 3-year overall survival (OS) for HCC patients (HR=1.798, 95%CI: 1.165~3.231, p=0.0321). Multivariate analysis showed that higher expression of cSMARCA5 was related to PVTT (HR=2.136, 95%CI: 1.130~5.218), AFP (>400ng/ml) (HR=2.335, 95%CI: 1.247~5.661), tumor size (>5cm) (HR=3.017, 95%CI: 1.477~5.659), poor histopathologic grading (HR=3.344, 95%CI: 2.175~6.143), and multiple tumor number (HR=2.875, 95%CI: 1.453~3.884). We also found that radiotherapy resistance was related to AFP (>400ng/ml) (OR=2.125, 95%CI: 1.015~3.348), tumor size (>5cm) (OR=2.857, 95%CI: 1.665~4.978), poor histopathologic grading (OR=2.463, 95%CI: 1.389~4.446), multiple tumor number (OR=2.332, 95%CI: 1.538~3.887), and high expression of cSMARCA5 (OR=3.574, 95%CI: 1.663~5.932). CONCLUSION: CircRNA-SMARCA5 is significantly increased in HCC tissues and promotes radiotherapy resistance. More importantly, higher expression level of cSMARCA5 is related to a poorer 3-year OS for patients with HCC.

Expression of matrix metalloproteinases and their association with clinical characteristics of solid tumors.

Matrix metalloproteinases (MMPs) are a group of zinc-dependent enzyme families that play an important role in regulating human physiological as well as pathological processes, especially in malignant tumors. Numerous experimental studies have shown that MMPs are not only involved in the occurrence and development of solid tumors but also play a key role in the staging and grading of tumors. The specific processes by which MMPs are involved in tumor cell invasion and metastasis mainly include degradation of the extracellular matrix, regulation of gene polymorphism, promotion of epithelial-mesenchymal transformation, and induction of adhesion molecule expression. The correlated expression of MMPs in different solid tumors provides a basis for tumor markers, tumor prognosis, and drug targets. In this review, the function, classification, and nomenclature of MMPs will be summarized, and the relevant expression of MMPs in solid tumors, as well as the clinical survival rate and general prognosis associated with MMPs, will be elaborated to provide useful information on which to base the search for new targets for tumor therapy.

Advances in Single-Cell Sequencing Technology and Its Applications in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and is mainly treated with chemotherapy-based combination therapy. In recent years, with the increasing development of global precision medicine, single-cell sequencing (SCS) has become one of the most promising technologies in the field of biotechnology. Moreover, the related application of this technology in TNBC has been applied and developed. By using SCS to study the heterogeneity of TNBC tumor cells, metastasis, drug resistance mechanisms, mutations, and cloning; it can further guide clinical chemotherapy, targeted therapy, and immunotherapy. To further reflect the importance of SCS in TNBC, this paper elaborated on and summarized the research and application progress of SCS in TNBC.

Dysregulation of lncRNA and circRNA Expression in Mouse Testes after Exposure to Triptolide.

BACKGROUND: Triptolide has been shown to exert various pharmacological effects on systemic autoimmune diseases and cancers. However, its severe toxicity, especially reproductive toxicity, prevents its widespread clinical use for people with fertility needs. Noncoding RNAs including lncRNAs and circRNAs are novel regulatory molecules that mediate a wide variety of physiological activities; they are crucial for spermatogenesis and their dysregulation might cause male infertility. However, whether they are involved in triptolide-induced reproductive toxicity is completely unknown. METHODS: After exposure of mice to triptolide, the total RNAs were used to investigate lncRNA/circRNA/mRNA expression profiles by strand-specific RNA sequencing at the transcriptome level to help uncover RNA-related mechanisms in triptolide-induced toxicity. RESULTS: Triptolide significantly decreased testicular weight, damaged testis and sperm morphology, and reduced sperm motility and density. Remarkable deformities in sperm head and tail were also found in triptolide-exposed mice. At the transcriptome level, the triptolide-treated mice exhibited aberrant expression profiles of lncRNAs/circRNAs/mRNAs. Gene Ontology and pathway analyses revealed that the functions of the differentially expressed lncRNA targets, circRNA cognate genes, and mRNAs were closely linked to many processes involved in spermatogenesis. In addition, some lncRNAs/circRNAs were greatly upregulated or inducibly expressed, implying their potential value as candidate markers for triptolide-induced male reproductive toxicity. CONCLUSION: This study provides a preliminary database of triptolide-induced transcriptome, promotes understanding of the reproductive toxicity of triptolide, and highlights the need for research on increasing the medical efficacy of triptolide and decreasing its toxicity.

Evaluation and application of constitutive promoters for cutinase production by Saccharomyces cerevisiae.

Cutinase as a promising biocatalyst has been intensively studied and applied in processes targeted for industrial scale. In this work, the cutinase gene tfu from Thermobifida fusca was artificially synthesized according to codon usage bias of Saccharomyces cerevisiae and investigated in Saccharomyces cerevisiae. Using the α-factor signal peptide, the T. fusca cutinase was successfully overexpressed and secreted with the GAL1 expression system. To increase the cutinase level and overcome some of the drawbacks of induction, four different strong promoters (ADH1, HXT1, TEF1, and TDH3) were comparatively evaluated for cutinase production. By comparison, promoter TEF1 exhibited an outstanding property and significantly increased the expression level. By fed-batch fermentation with a constant feeding approach, the activity of cutinase was increased to 29.7 U/ml. The result will contribute to apply constitutive promoter TEF1 as a tool for targeted cutinase production in S. cerevisiae cell factory.