An atlas of epithelial cell states and plasticity in lung adenocarcinoma.

Understanding the cellular processes that underlie early lung adenocarcinoma (LUAD) development is needed to devise intervention strategies1. Here we studied 246,102 single epithelial cells from 16 early-stage LUADs and 47 matched normal lung samples. Epithelial cells comprised diverse normal and cancer cell states, and diversity among cancer cells was strongly linked to LUAD-specific oncogenic drivers. KRAS mutant cancer cells showed distinct transcriptional features, reduced differentiation and low levels of aneuploidy. Non-malignant areas surrounding human LUAD samples were enriched with alveolar intermediate cells that displayed elevated KRT8 expression (termed KRT8+ alveolar intermediate cells (KACs) here), reduced differentiation, increased plasticity and driver KRAS mutations. Expression profiles of KACs were enriched in lung precancer cells and in LUAD cells and signified poor survival. In mice exposed to tobacco carcinogen, KACs emerged before lung tumours and persisted for months after cessation of carcinogen exposure. Moreover, they acquired Kras mutations and conveyed sensitivity to targeted KRAS inhibition in KAC-enriched organoids derived from alveolar type 2 (AT2) cells. Last, lineage-labelling of AT2 cells or KRT8+ cells following carcinogen exposure showed that KACs are possible intermediates in AT2-to-tumour cell transformation. This study provides new insights into epithelial cell states at the root of LUAD development, and such states could harbour potential targets for prevention or intervention.

EDTA plasma in glass and polyethylene terephthalate tubes is suitable for measurement of B-type natriuretic peptide on the Mindray CL-6000i.

AIMS: To explore differences in B-type natriuretic peptide (BNP) concentration and stability and evaluate BNP accuracy in different collection tubes. METHODS: BNP concentrations in heparin/glass, EDTA/glass, and EDTA/polyethylene terephthalate (PET) tubes were measured on the Mindray CL-6000i at 0.5, 1, 2, and 4 h after collection. Differences were evaluated using Wilcoxon's paired tests and Bland-Altman plots. BNP stability and measurement accuracies were estimated using Kruskal-Wallis H tests and recovery tests. RESULTS: BNP concentrations in EDTA/glass tubes were 31.4% higher than those in heparin/glass tubes and 3.04% lower than those in EDTA/PET tubes. BNP stability significantly decreased in the heparin/glass tube. BNP remained stable in EDTA/glass and EDTA/PET tubes at room temperature for 4 h. BNP recovery rates in heparin/glass, EDTA/glass, and EDTA/PET tubes were 77.46, 86.04, and 88.23%, respectively. CONCLUSIONS: Plasma in EDTA/glass and EDTA/PET tubes is suitable for BNP measurement on the Mindray CL-6000i.

Genome-wide investigation and expression pattern of PHR family genes in cotton under low phosphorus stress.

Phosphorus starvation response (PHR) protein is an important transcription factor in phosphorus regulatory network, which plays a vital role in regulating the effective utilization of phosphorus. So far, the PHR genes have not been systematically investigated in cotton. In the present study, we have identified 22, 23, 41 and 42 PHR genes in G. arboreum, G. raimondii, G. hirsutum and G. barbadense, respectively. Phylogenetic analysis showed that cotton PHR genes were classified into five distinct subfamilies. The gene structure, protein motifs and gene expression were further investigated. The PHR genes of G. hirsutum from the same subfamily had similar gene structures, all containing Myb_DNA-binding and Myb_CC_LHEQLE conserved domain. The structures of paralogous genes were considerably conserved in exons number and introns length. The cis-element prediction in their promoters showed that genes were not only regulated by light induction, but also were related to auxin, MeJA, abscisic acid-responsive elements, of which might be regulated by miRNA. The expression analysis showed that the GhPHR genes were differentially expressed in different tissues under various stresses. Furthermore, GhPHR6, GhPHR11, GhPHR18 and GhPHR38 were significantly changed under low phosphorus stress. The results of this study provide a basis for further cloning and functional verification of genes related to regulatory network of low phosphorus tolerance in cotton.

Loss of CD73 shifts transforming growth factor-ß1 (TGF-ß1) from tumor suppressor to promoter in endometrial cancer.

In many tumors, CD73 (NT5E), a rate-limiting enzyme in adenosine biosynthesis, is upregulated by TGF-ß and drives tumor progression. Conversely, CD73 is downregulated in endometrial carcinomas (EC) despite a TGF-ß-rich environment. Through gene expression analyses of normal endometrium samples of the uterine cancer TCGA data set and genetic and pharmacological studies, we discovered CD73 loss shifts TGF-ß1 from tumor suppressor to promoter in EC. TGF-ß1 upregulated CD73 and epithelial integrity in vivo in the normal endometrium and in vitro in early stage EC cells. With loss of CD73, TGF-ß1-mediated epithelial integrity was abrogated. EC cells developed TGF-ß1-mediated stress fibers and macromolecule permeability, migration, and invasion increased. In human tumors, CD73 is downregulated in deeply invasive stage I EC. Consistent with shifting TGF-ß1 activity, CD73 loss increased TGF-ß1-mediated canonical signaling and upregulated cyclin D1 (CCND1) and downregulated p21 expression. This shift was clinically relevant, as CD73Low/CCND1High expression associated with poor tumor differentiation, increased myometrial and lymphatic/vascular space invasion, and patient death. Further loss of CD73 in CD73Low expressing advanced stage EC cells increased TGF-ß-mediated stress fibers, signaling, and invasiveness, whereby adenosine A1 receptor agonist, CPA, dampened TGF-ß-mediated invasion. These data identify CD73 loss as essential for shifting TGF-ß activity in EC.