DNA and cell biology最新文献

Previous findings have indicated a marked upregulation of SNORA71A in gallbladder cancer (GBC) tissues compared to normal samples. However, the precise role and molecular mechanisms of SNORA71A in GBC remain largely unknown. Moreover, gemcitabine (GEM) drug resistance has been found to lead to unfavorable outcomes and recurrence in GBC patients. Therefore, this study aims to investigate the impact of SNORA71A on GBC and explore its potential effects on the sensitivity of GBC cells to GEM. RT-qPCR was conducted to assess SNORA71A level in matched normal and GBC tissues. Cell proliferation was examined through CCK-8 and 5-ethynyl-2'-deoxyuridine (EdU) assays. Additionally, the expression of proteins in GBC cells was analyzed using western blot assay. The level of SNORA71A was notably higher in GBC tissues relative to normal tissues. SNORA71A overexpression led to increased GBC cell proliferation and invasion. Conversely, SNORA71A deficiency strongly suppressed GBC cell proliferation and invasion and triggered cell apoptosis and ferroptosis. Additionally, downregulation of SNORA71A obviously enhanced the antiproliferative and anti-invasive effects of GEM on GBC cells, whereas these changes were reversed by inhibiting ferroptosis. Furthermore, deficiency of SNORA71A further augmented the GEM-induced downregulation of p-Akt, Nrf2, and GPX4 in NOZ cells; however, these effects were reversed by ferroptosis inhibition. Collectively, these findings suggested that downregulation of SNORA71A may increase the sensitivity of GBC cells to GEM by triggering ferroptosis through inhibiting the AKT/NRF2/GPX4 signaling pathway.

Radiation-induced intestinal injury is one of the most common intestinal complications caused by pelvic and abdominal tumor radiotherapy, severely impacting patients' quality of life. Ionizing radiation, while killing tumor cells, inevitably damages healthy tissue. Radiation-induced enteropathy results from radiation therapy-induced intestinal tissue damage and inflammatory responses. This damage involves various complex molecular mechanisms, including cell apoptosis, oxidative stress, release of inflammatory mediators, disruption of immune responses, and imbalance of intestinal microbiota. A thorough understanding of these molecular mechanisms is crucial for developing effective prevention and treatment strategies.

One of the main health issues in the modern world is cancer, with breast cancer (BC) as one of the most common types of malignancies. Different environmental and genetic risk factors are involved in the development of BC. One of the primary genes implicated in cancer development is the p53 gene, which is also known as the "gatekeeper" gene. p53 is involved in cancer development by interacting with numerous pathways and signaling factors, including microRNAs (miRNAs). miRNAs are small noncoding RNA molecules that regulate gene expression by binding to the 3' untranslated region of target mRNAs, resulting in their translational inhibition or degradation. If the p53 gene is mutated or degraded, it can contribute to the risk of BC by disrupting the expression of miRNAs. Similarly, the disruption of miRNAs causes the negative regulation of p53. Therefore, the p53/miRNA axis is a crucial pathway in the progression or prevention of BC, and understanding the regulation and function of this pathway may contribute to the development of new therapeutic strategies to help treat BC.

Circular RNAs (circRNAs) and eukaryotic translation initiation factor 4A3 (EIF4A3) have been reported to participate in the pathogenesis of nasopharyngeal carcinoma (NPC), but their mechanism has not been fully understood. This research aimed to confirm the role and regulatory mechanism of hsa_circ_0049396 interacting with EIF4A3 in NPC tumorigenesis. Quantitative real time polymerase chain reaction (qRT-PCR) was executed to detect the levels of hsa_circ_0049396 and EIF4A3. Cell function experiments and nude mice xenograft assay were used to confirm the role of hsa_circ_0049396 in NPC. The regulatory effect of EIA4A3 on hsa_circ_0049396 was determined by circInteractome prediction, RNA binding protein immunoprecipitation (RIP) assay, and qRT-PCR. In addition, the Hippo-YAP pathway-related proteins and EIF4A3 protein were detected by western blotting. hsa_circ_0049396 was proved to be downregulated in NPC samples, and its low expression indicated the poor prognosis of NPC. After upregulating hsa_circ_0049396 in NPC cells, the proliferation, migration, invasion, and tumor growth in vivo were suppressed by inhibiting the Hippo-YAP pathway. Moreover, EIF4A3 bound to the flanking regions of the hsa_circ_0049396 to enhance hsa_circ_0049396 expression in NPC cells. hsa_circ_0049396 mediated by EIF4A3 in NPC can attenuate NPC tumorigenesis by inhibiting the Hippo-YAP pathway. This finding may provide a potential early diagnostic biomarker or drug target to improve the precision medicine approaches of NPC.

Skin homeostasis relies on a delicate balance between host proteases and protease inhibitors along with those secreted from microbial communities, as disruption to this harmony contributes to the pathogenesis of inflammatory skin disorders, including atopic dermatitis and Netherton's syndrome. In addition to being a prominent cause of skin and soft tissue infections, the gram-positive bacterium Staphylococcus aureus is a key player in inflammatory skin conditions due to its array of 10 secreted proteases. Herein we review how S. aureus proteases augment the development of inflammation in skin disorders. These mechanisms include degradation of skin barrier integrity, immune dysregulation and pruritis, and impairment of host defenses. Delineating the diverse roles of S. aureus proteases has the potential to reveal novel therapeutic strategies, such as inhibitors of proteases or their cognate target, as well as neutralizing vaccines to alleviate the burden of inflammatory skin disorders in patients.

Isoorientin (ISO) is a naturally occurring flavonoid with diverse functional properties that mitigate the risk of diseases stemming from oxidation, inflammation, and cancer cell proliferation. P-glycoprotein (P-gp) is a vital component of the intestinal epithelium and may play a role in the onset of intestinal inflammatory conditions, such as inflammatory bowel disease (IBD). Recent studies have suggested that short-chain fatty acids (SCFAs) and secondary bile acids (SBAs) produced by the gut microbiota stimulate the increase of P-gp expression, alleviating excessive inflammation and thereby preservation of intestinal homeostasis. ISO has been shown to improve colon health and modulate the gut microbiota. In this study, we aimed to explore whether ISO can modulate the microbes and their metabolites to influence P-gp expression to alleviate IBD. First, the impact of ISO on dextran sulfate sodium (DSS)-treated colitis in mice was investigated. Second, 16S rRNA gene sequencing was conducted. The present study indicated that ISO mitigated the symptoms and pathological damage associated with DSS-treated colitis in mice. Western blot analysis revealed ISO upregulated P-gp in colon tissues, suggesting the critical role of P-gp protein in intestinal epithelial cells. 16S microbial diversity sequencing revealed ISO restored the richness and variety of intestinal microorganisms in colitis-bearing mice and enriched SCFA-producing bacteria, such as Lachnospiraceae_NK4A136_group. The experiments also revealed that the ISO fecal microbiota transplantation (FMT) inoculation of DSS-treated mice had similarly beneficial results. FMT mice showed a reduction in colitis symptoms, which was more pronounced in ISO-FMT than in CON-FMT mice. Meanwhile, ISO-FMT expanded the abundance of beneficial microorganisms, increased the expression of metabolites, such as SCFAs and total SBAs, and significantly upregulated the expression of P-gp protein. In addition, Spearman's correlation analysis demonstrated a positive correlation between the production of SCFAs and SBAs and the expression of P-gp. The present study identified that ISO increases the expression of P-gp in the intestinal epithelium by regulating intestinal microorganisms and their metabolites, which maintains colonic homeostasis, improves the integrity of the colonic epithelium, and alleviates colitis.

Cardiovascular and cerebrovascular diseases (CCVDs) significantly contribute to global mortality and morbidity due to their complex pathogenesis involving multiple biological processes. Ferroptosis is an important physiological process in CCVDs, manifested by an abnormal increase in intracellular iron concentration. MiRNAs, a key class of noncoding RNA molecules, are crucial in regulating CCVDs through pathways like glutathione-glutathione peroxidase 4, glutamate/cystine transport, iron metabolism, lipid metabolism, and other oxidative stress pathways. This article summarizes the progress of miRNAs' regulation on CCVDs, aiming to provide insights for the diagnosis and treatment of CCVDs.

SYT13 is one of the atypical members of the synaptotagmin (SYT) family whose function has attracted considerable attention in recent years. Although SYT13 has been studied in several types of human cancers, such as lung cancer, its role in esophageal squamous cell carcinoma (ESCC) is still unclear. It was demonstrated that SYT13 is significantly upregulated in ESCC tissues compared with normal ones and correlated with higher degree of malignancy. Knockdown of SYT13 could inhibit ESCC cell proliferation and migration, while promoting cell apoptosis. Meanwhile, ESCC cells with relatively lower SYT13 expression grew slower in vivo and finally formed smaller xenografts. Furthermore, acrosomal vesicular protein 1 was identified as a potential downstream target of SYT13, which regulates cell phenotypes of ESCC cells in cooperation with SYT13. All the in vitro and in vivo results in this study identified that SYT13 silencing could be an effective strategy to inhibit the development of ESCC, which could be considered as a promising therapeutic target in the treatment of ESCC.

We aim to explore the potential mechanism of bone marrow mesenchymal stem cells-derived extracellular vesicles (BMSCs-Exo) in improving spinal cord injury (SCI). Thirty male 12-week specific pathogen-free (SPF) Sprague-Dawley (SD) rats were used to construct SCI model in vivo. Ten male 12-week SPF SD rats were used to extract BMSCs. The Basso, Beattie, Bresnahan (BBB) score was used to evaluate the motor function of rats. Real-time fluorescence quantitative PCR (RT-PCR), western blot (WB), and double luciferase assay were used to explore the regulation between rno-miR-208a-3p and Cdkn1a (p21) in BMSCs. Primary spinal cord neurons were treated with lipopolysaccharide (100 ng/mL) for 30 min to mimic SCI in vitro. Compared with the model group (14 scores), BMSCs-Exo increased BBB score (19 scores) in SCI rats. Compared with the sham group, Cdkn1a was upregulated, whereas rno-miR-208a-3p was downregulated in the model group. However, compared with the model group, Cdkn1a was downregulated, whereas rno-miR-208a-3p was upregulated in the BMSCs-Exo group. In addition, rno-miR-208a-3p inhibited the expression of Cdkn1a via direct binding way. BMSCs-Exo-rno-miR-208a-3p promoted the proliferation of primary spinal neurons via inhibiting apoptosis in vitro. Moreover, BMSCs-Exo-rno-miR-208a-3p promoted cyclin D1, CDK6, and Bcl-2 and inhibited Bax expression in a cell model of SCI. In conclusion, BMSCs-Exo-carried rno-miR-208a-3p significantly protects rats from SCI via regulating the Cdkn1a pathway.

Plasmodium parasites, the causative agents of malaria, rely on sophisticated cellular mechanisms to survive and proliferate within their hosts. Plasmodium complex life cycle requires posttranslational modifications (PTMs) to control cellular activities. Neddylation is a type of PTM in which NEDD8 is covalently attached to target proteins and plays an important role in cell cycle control and metabolism. Covalent attachment to its substrates requires the Nedd8-activating enzyme, E1; the NEDD8-conjugating enzyme, E2; and the ligase, E3. In Plasmodium, protein neddylation is essential for parasite development during the stage I-II transition from zygote to ookinete differentiation and malaria transmission. Here, we discuss the current understanding of protein neddylation in Plasmodium, which is involved in malaria transmission.