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Background Several somatic mutation hotspots were recently identified in the TERT promoter region in human cancers. Large scale studies of these mutations in multiple tumor types are limited, in particular in Asian populations. This study aimed to: analyze TERT promoter mutations in multiple tumor types in a large Chinese patient cohort, investigate novel tumor types and assess the functional significance of the mutations. Methods TERT promoter mutation status was assessed by Sanger sequencing for 13 different tumor types and 799 tumor tissues from Chinese cancer patients. Thymic epithelial tumors, gastrointestinal leiomyoma, and gastric schwannoma were included, for which the TERT promoter has not been previously sequenced. Functional studies included TERT expression by RT-qPCR, telomerase activity by the TRAP assay, and promoter activity by the luciferase reporter assay. Results TERT promoter mutations were highly frequent in glioblastoma (83.9%), urothelial carcinoma (64.5%), oligodendroglioma (70.0%), medulloblastoma (33.3%), and hepatocellular carcinoma (31.4%). C228T and C250T were the most common mutations. In urothelial carcinoma, several novel rare mutations were identified. TERT promoter mutations were absent in GIST, thymic epithelial tumors, gastrointestinal leiomyoma, gastric schwannoma, cholangiocarcinoma, gastric and pancreatic cancer. TERT promoter mutations highly correlated with upregulated TERT mRNA expression and telomerase activity in adult gliomas. These mutations differentially enhanced the transcriptional activity of the TERT core promoter. Conclusions TERT promoter mutations are frequent in multiple tumor types and have similar distributions in Chinese cancer patients. The functional significance of these mutations reflect the importance to telomere maintenance and hence tumorigenesis, making them potential therapeutic targets.

Substantial evidence indicated that low birth weight was an independent risk factor for obesity, impaired glucose regulation, and diabetes later in life. However, investigations into the association between low birth weight and placental microbiome in full-term neonates are limited. Placentas were collected from low birth weight (LBW) and normal birth weight (NBW) full-term neonates (gestational age 37 w0d–41 w6d) consecutively born at Peking Union Medical College Hospital. The anthropometric measurements were measured and 16S ribosomal DNAamplicon high-throughput sequencing were utilized to define bacteria within placenta tissues. It showed that birth weight, ponderal index, head circumference, and placenta weight were significantly lower in LBW than NBW neonates (p < 0.05). The operational taxonomic units (OTUs) (p < 0.05) and the estimators of community richness (Chao) indexes (p < 0.05) showed a significantly lower diversity in LBW than NBW neonates. There were significant variations in the composition of placenta microbiota between the LBW and NBW neonates at the phylum and genus level. Furthermore, it indicated that Lactobacillus percentage was positively associated with birth weight (r = 0.541, p = 0.025). In conclusion, our present study for the first time detected the relationship between birth weight and placental microbiome profile in full-term neonates. It is novel in showing that the placental microbiome varies in association with low birth weight in full-term neonates.