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Lan Li

Publications and source records attributed to Lan Li.

5 recordsLinked to original sources

CRISPR/Cas9 screening revealed BIRC6-AS1/BIRC6 mediates abiraterone resistance via NHEJ pathway-dependent A20 degradation in prostate cancer.

Abiraterone acetate is a standard-of-care therapy for prostate cancer (PCa). However, resistance frequently emerges, often characterized by the progression to AR-independent phenotypes. Employing a genome-wide CRISPR/Cas9 library screening strategy, we identified 523 long non-coding RNAs (lncRNAs) and 2,183 protein-coding genes as potential candidates associated with abiraterone resistance. Notably, a pair of sense-antisense genes, BIRC6-AS1/BIRC6, was identified as a significant contributor to abiraterone resistance, serving as a critical survival factor in AR-independent contexts. BIRC6-AS1 depletion led to a reduction in both the mRNA and protein levels of BIRC6. Moreover, depletion of either BIRC6-AS1 or BIRC6 enhanced the sensitivity of PCa cells to abiraterone in both in vitro and in vivo settings. Further investigation revealed that BIRC6-AS1 stabilized the mRNA of BIRC6 through interaction with ILF2. Suppression of either BIRC6-AS1 or BIRC6 attenuated non-homologous end joining (NHEJ) repair activity, resulting in the disassembly of 53BP1 foci at DNA damage sites and an increased accumulation of DNA damage, thereby exposing a vulnerability in AR-independent resistant cells. Mechanistically, BIRC6 interacted with A20 and facilitated the K48-linked ubiquitination and subsequent degradation of A20 at the K337 residue. Additionally, A20 knockdown effectively reversed the abiraterone sensitivity induced by BIRC6-AS1 depletion. Collectively, our study provides a landscape of lncRNAs and protein-coding genes associated with abiraterone resistance and suggests that targeting the BIRC6-AS1/BIRC6 axis represents a potential therapeutic strategy to eradicate AR-independent resistant tumors in prostate cancer.

Journal Article↗

VIPase autoantibodies in Fas-defective mice and patients with autoimmune disease.

The immunoregulatory neuropeptide vasoactive intestinal peptide (VIP) was cleaved by purified IgG from Fas-defective C3H/gld mice, lupus patients, and autoimmune thyroiditis patients. No VIPase activity was detected in IgG from control mice and humans. Kinetic analyses of VIPase IgG preparations suggested low-affinity recognition of VIP. Yet the VIPase activity was VIP selective, judged by lack of correlation with other protease activities expressed by the IgG and by noninterference of unrelated peptides in the activity. Recombinant Fv constructs selected from a human lupus phage show library displayed VIPase activity, confirming that the active site is located in the V domains. Inhibition of the VIPase activity by di-isopropylfluorophosphate suggested a serine protease-like mechanism of catalysis. Irreversible binding of a biotinyated phosphonate diester by the IgG and Fv preparations was observed, consistent with the presence of activated nucleophiles similar to those in enzymes capable of covalent catalysis. These observations show that VIP is a target for specific catalytic autoantibodies in autoimmune disease.

Animals↗

[Newborn tracheotomy without tracheal intubation].

OBJECTIVE: To approach the tracheotomy in newborn without tracheal intubation in emergency. METHOD: Five cases hospitalized between March 1998 and March 2002 were reviewed retrospectively. The mean age was 19 days from 5 hours to 24 days after born. All patients accepted the operation without tube insertion in trachea because of the primary disease. RESULT: The operation was performed successfully in all cases. One case died of severe respiratory and circulatory failure. Four cases were decannulated with the primary disease cured. CONCLUSION: Preoperative evaluation and ideal timing of tracheotomy are very important for the newborn infant. Intensive postoperation nursing are recommended.

Cysts↗

Increased beta -oxidation but no insulin resistance or glucose intolerance in mice lacking adiponectin.

Previous reports showed that recombinant fragments of adiponectin (adipo) displayed pharmacological effects when injected into rodents, but the relevance of these observations to the physiological function of adipo is unclear. We generated Adipo(-/-) mice by gene targeting. Adipo(-/-) mice are fertile with normal body and fat pad weights. Plasma glucose and insulin levels of Adipo(-/-) and Adipo(+/+) mice are similar under fasting conditions and during an intraperitoneal glucose tolerance test (GTT). Insulin tolerance test (ITT) also produces similar plasma glucose and insulin levels in the two groups of mice. Hyperinsulinemic-euglycemic clamp analysis showed that Adipo(-/-) and Adipo(+/+) mice have similar glucose infusion rates to maintain a similar serum glucose. High-fat diet feeding for 7 months led to similar weight gain and similar GTT and ITT responses. We next measured beta-oxidation and found it to be significantly increased in muscle and liver of Adipo(-/-) mice. In conclusion, our study indicates that absence of adipo causes increased beta-oxidation but does not cause glucose intolerance or insulin resistance in mice.

Adiponectin↗

Cbfa1-independent decrease in osteoblast proliferation, osteopenia, and persistent embryonic eye vascularization in mice deficient in Lrp5, a Wnt coreceptor.

The low-density lipoprotein receptor-related protein (Lrp)-5 functions as a Wnt coreceptor. Here we show that mice with a targeted disruption of Lrp5 develop a low bone mass phenotype. In vivo and in vitro analyses indicate that this phenotype becomes evident postnatally, and demonstrate that it is secondary to decreased osteoblast proliferation and function in a Cbfa1-independent manner. Lrp5 is expressed in osteoblasts and is required for optimal Wnt signaling in osteoblasts. In addition, Lrp5-deficient mice display persistent embryonic eye vascularization due to a failure of macrophage-induced endothelial cell apoptosis. These results implicate Wnt proteins in the postnatal control of vascular regression and bone formation, two functions affected in many diseases. Moreover, these features recapitulate human osteoporosis-pseudoglioma syndrome, caused by LRP5 inactivation.

Animals↗