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Jun Tang

Publications and source records attributed to Jun Tang.

3 recordsLinked to original sources

scAmp enables focal gene amplification analysis from single-cell data.

Oncogene amplification on extrachromosomal DNA is a common driver of tumor progression and is associated with acquired drug resistance and poor patient survival. While bulk whole genome sequencing studies have revealed the landscape of genes amplified on extrachromosomal DNA in tumors, it remains challenging to study the subclonal heterogeneity and functional (e.g., transcriptomic) consequences of extrachromosomal DNA on tumors. To address this, we introduce scAmp: a probabilistic algorithm for detecting and analyzing extrachromosomal DNA from single-cell datasets. Using well-characterized cell lines, we demonstrate that scAmp has improved specificity over bulk genome sequencing in predicting extrachromosomal DNA status and can resolve the status of chromosomal amplifications that were historically extrachromosomal. We further showcase scAmp by analyzing 73 patient tumors profiled with single-cell assay for transposase-accessible chromatin by sequencing, where we characterize the subclonal evolution of subclones with extrachromosomal DNA and identify the effect of these amplifications on the chromatin accessibility landscape of cancer cells. Finally, we provide proof-of-concept analyses that scAmp aids in the detection of extrachromosomal DNA from clinical histopathology assays. Together, we anticipate that scAmp will broadly enable further studies - both retrospective and prospective - that dissect critical questions of how extrachromosomal DNAs affect cancer cells and the tumors in which they reside.

Humans

Meta-analysis of prostacyclin therapy for persistent pulmonary hypertension with congenital diaphragmatic hernia.

OBJECTIVE: To evaluate the efficacy and safety of prostacyclin in the treatment of persistent pulmonary hypertension in congenital diaphragmatic hernia. METHODS: A systematic literature search was conducted in four main databases (PubMed, Web of Science, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL). The protocol was registered in advance in the International Prospective of Systematic Reviews (CRD420261325458). RESULTS: A total of nine studies were included involving a total of 7009 infants in this systematic review and meta-analysis. GRADE assessment revealed substantial heterogeneity in the quality of evidence across outcomes, with most outcomes rated very low quality and only one rated moderate quality. Studies were performed meta-analysis, which showed the use of prostacylin resulted a statistically significant decrease in the OI compared to the control group (Mean Difference (MD), 9.34; I2 0%; p < 0.00001), no statistically significant in mortality (OR, 0.83; I2 84%; p = 0.70), ECMO (OR = 4.9; I2 98%; p = 0.27), BNP (std MD, 6.98; I2 98%; p = 0.31), FiO2 (SMD = 8.0;, I2 64%; p = 0.11), Systolic orientation of IVS curvature (SMD = 0.69; I2 97%; p = 0.32), Diastolic orientation of IVS differences (MD = 0.62; I2 93% p = 0.26). After applying the Hartung-Knapp adjustment, with the exception of BNP, the pooled effects of the other outcomes were not statistically significant, and there was high heterogeneity in measures such as ECMO and ventricular septal curvature. CONCLUSION: In conclusion, this meta-analysis has confirmed that prostacyclin may temporarily improve oxygenation. However, after applying the Hartung-Knapp adjustment, with the exception of BNP, the pooled effects of the other outcomes were not statistically significant, and there was high heterogeneity in measures such as ECMO and ventricular septal curvature. Further validation through high-quality studies are still needed. TRIAL REGISTRATION: PROSPERO: CRD420261325458.

Humans

The evolutionary dynamics of extrachromosomal DNA in human cancers.

Oncogene amplification on extrachromosomal DNA (ecDNA) is a common event, driving aggressive tumor growth, drug resistance and shorter survival. Currently, the impact of nonchromosomal oncogene inheritance-random identity by descent-is poorly understood. Also unclear is the impact of ecDNA on somatic variation and selection. Here integrating theoretical models of random segregation, unbiased image analysis, CRISPR-based ecDNA tagging with live-cell imaging and CRISPR-C, we demonstrate that random ecDNA inheritance results in extensive intratumoral ecDNA copy number heterogeneity and rapid adaptation to metabolic stress and targeted treatment. Observed ecDNAs benefit host cell survival or growth and can change within a single cell cycle. ecDNA inheritance can predict, a priori, some of the aggressive features of ecDNA-containing cancers. These properties are facilitated by the ability of ecDNA to rapidly adapt genomes in a way that is not possible through chromosomal oncogene amplification. These results show how the nonchromosomal random inheritance pattern of ecDNA contributes to poor outcomes for patients with cancer.

Biological Evolution