Ovine pulmonary adenocarcinoma (OPA), caused by the jaagsiekte sheep retrovirus (JSRV), is a chronic, progressive, and contagious lung tumor that seriously affects sheep production. It also represents a valuable animal model for several human lung adenocarcinomas. However, little is known about the role of autophagy in OPA tumorigenesis. Here, Western blotting combined with transmission electron microscopy examination and Cyto-ID dye staining was employed for evaluation of changes of autophagic levels. The results of the present study showed that expression of the autophagy marker proteins Beclin-1 and LC3 was decreased in OPA lung tissues, as well as in cells overexpressing the envelope glycoprotein of JSRV (JSRV Env). Reduced numbers of autophagosomes were also observed in cells overexpressing JSRV Env, although assessment of autophagic flux showed that JSRV Env overexpression did not block the formation of autophagosomes, suggesting increased degradation of autolysosomes. Last, mouse xenograft experiments indicated that inhibition of autophagy by 3-methyladenine suppressed both tumor growth and the epithelial-to-mesenchymal transition. In conclusion, JSRV, through JSRV Env, takes advantage of the autophagy process, leading to the development of OPA.

Background The genomic features of cancer cells may confer the metastatic ability of lung adenocarcinoma (LUAD) to metastasize to specific organs. We aimed to identify the differences in genomic alterations between patients with primary LUAD with and without metastases and to elucidate the metastatic biology that may help developing biomarker-directed therapies for advanced or metastatic disease. Methods A retrospective cohort of 497 patients with LUAD including 388 primary tumors (PR), 53 bone metastases (MT-bone), 30 liver metastases (MT-liver), and 26 brain metastases (MT-brain) was tested for genomic alterations by a next-generation sequencing assay. Results The EGFR, TP53, TERT, LRP1B, CDKN2A, ERBB2, ALK, and KMT2C genes had a high frequency of mutations, and the mutations were shared by PR and metastases groups. TP53 and EGFR were the most common mutated genes. In comparison with PR, KRAS, STK11, ATM, NPM1, and ROS1 were significantly mutated in MT-brain, and TP53, MYC, RSPO2, CDKN2a, and CDKN2B were significantly mutated in MT-liver. The frequencies of TP53, CDKN2A, MTAP, PRKCI, and APC mutations were higher in MT-bone than that in PR. The ERBB, phosphoinositide-3-kinase/protein kinase B (PI3K-AKT), cell cycle, Fibroblast growth factor (FGF), and homologous recombination deficiency signaling pathways were affected in both PR and metastases, and there is higher frequency of mutations in metastases. Moreover, the co-mutations in patients with PR and metastasis were respectively analyzed. In addition, the programmed death ligand 1 (PD-L1) level was obviously related to tumor stage and tumor metastases, and the tumor mutational burden was correlated to clinicopathological features including age, gender, pathological stages, and tumor metastases. FGFR1, KAT6A, MYC, RAD21, TP53, and DAXX were also dramatically correlated to the tumor mutational burden. Conclusion Metastases are the most devastating stage of tumors and the main cause of cancer-related deaths. Our results provided a clinically relevant view of the tumor-intrinsic mutational landscape of patients with metastatic LUAD.

Background: Lung cancer remains the leading cause of oncological death. There is an urgent need to discover new molecular targets and to develop new treatments. Our previous study showed that one of the UDP-glucuronosyltransferases (UGTs) family, UGT1A3, is an important prognostic factor for lung adenocarcinoma (LUAD), inhibiting UGT1A3 could significantly improve the efficacy of anti-tumor drugs. In this study, we aimed to explore the upstream transcriptional factor (USF1) of UGT1A3 and its way of playing a role in LUAD. Methods: The UGT1A3 promoter region was analyzed and dual-luciferase assay was involved to explore whether USF1 could bind to this region, and the possible regulation effects of USF1 to UGT1A3 was indicated by siRNA and recovery experiment. Then, the Cancer Genome Atlas database was used to analyze USF1 clinical features. The expression level of USF1 was detected by immunohistochemical assay and Western blotting. Cellular viability, proliferation, migration and invasion potential were also investigated. Meanwhile, the effect of USF1 in LUAD progression was detected in a mouse model. The downstream signaling pathway was analyzed by bioinformatic analysis and the expression of all related proteins was detected. Results: UGT1A3 was transcriptionally regulated by USF1, which was highly expressed in all investigated samples including patients' tissues, studied cells lines, and mouse models. The knockdown of USF1 inhibited cells viability, proliferation, migration and invasion, and reduced the tumor volume. Moreover, USF1 promoted the progress of LUAD by regulating the neurotrophin signaling pathway. Conclusion: As an important transcriptional regulator of UGT1A3, USF1 was highly expressed in LUAD and promoted LUAD progression by regulating the neurotrophin signaling pathway. These findings provide a new theoretical data that could serve as a good foundation for the treatment of LUAD.

Estimated glomerular filtration rate (EGFR)-sensitive mutations are extremely important for targeted treatment strategies in lung cancer. Osimertinib can effectively inhibit the activity of EGFR-sensitive mutations, including the T790M mutation. However, the efficiency of osimertinib for rare mutation types of T790 is unclear. Here, we report the case of a Chinese patient with lung adenocarcinoma (LADC) harboring a T790I mutation who achieved significant benefits from osimertinib treatment.

Background: We aimed at investigation of the effect and the underlying neurotrophin signaling pathway of the upstream transcription factor 1 (USF1) in lung adenocarcinoma (LUAD). Methods: The Cancer Genome Atlas (TCGA) database was used to analyze USF1 expression data and to extract patients’ clinical records. Immunohistochemical assay and Western blotting (WB) were used to determine the expression levels of USF1 in LUAD. The neurotrophin signaling pathway was analyzed by bioinformatic analysis while the expression of all related proteins was determined by WB. In addition cellular viability, proliferation, migration and invasion potential were investigated by the CCK-8, colony formation, wound healing and transwell. Meanwhile, the effect of USF1 in LUAD progression was investigated in a mouse model. The link between USF1 and UGT1A3 (UDP Glucuronosyltransferase Family 1 Member A3) was studied by the dual-luciferase reporter assay. Results: We have detected a high expression level of USF1 in LUAD, which was associated with advanced tumor stage, nodal metastasis, and poor patient’s survival rate. The knockdown of USF1 inhibited cellular viability, proliferation, migration and invasion. Meanwhile, USF1 knockdown inhibited tumor growth in a mouse model. Besides, USF1 targeted UGT1A3, which was proven by the fact that the USF1 knockdown decreased the expression level of UGT1A3, whereas the upregulated expression of UGT1A3 increased cellular viability and proliferation. We have proved that the neurotrophin signaling pathway in LUAD was activated by USF1 and UGT1A3. The expression of the related proteins was also inhibited by the USF1 knockdown, while the overexpression of IRAK increased cancer cells’ migration and invasion potential. Conclusion: USF1 was highly expressed in LUAD and promoted LUAD progression by regulating the neurotrophin signaling pathway. These findings provide a new theoretical data that could serve as a good foundation for the treatment of LUAD.

Objective To investigate the levels of trimethylated histone 3 at lysine residue 27 (H3K27me3) and its modification enzymes Zeste gene enhancer homolog 2 (EZH2), lysine-specific demethylase 6B (Kdm6B/JMJD3) and lysine-specific demethylase 6A (Kdm6A/UTX) in tissues and organs of 7-day and 2-month postnatal mice. Methods Immunohistochemistry was used to detect the expressions of H3K27me3 and its modification enzymes EZH2, JMJD3 and UTX in the brain, salivary glands, back fat, thymus, lung, heart, stomach, intestines, liver, testes, and skin of 7-day and 2-month mice. Real-time quantitative PCR was used to confirm the results. The relationships between H3K27me3 and its modification enzymes were analyzed statistically. Results Immunohistochemistry showed H3K27me3 persistently present in all examined tissues of 7-day and 2-month mice. EZH2 was persistently expressed in the brain, heart, liver, and skin of 7-day and 2-month mice, but only expressed in the salivary glands, adipose tissues, thymus, lung, intestines, and testes of 2-month mice. JMJD3 was expressed in the brain, salivary glands, adipose tissues, lung, heart, stomach, intestines, testes, skin of 7-day mice, but was not expressed in the lung, adipose tissues and stomach of 2-month mice. UTX was expressed in the brain, salivary glands, adipose tissues, lung, heart, testes, skin of 7-day mice, but only expressed in the testes of 2-month mice. Most mRNA of H3K27 modification enzymes were moderately or highly expressed as their immunohistochemical results were positive. Conclusion There was H3K27me3 persistently present in the all examined tissues at different stages. EZH2 was mostly expressed in the brain, salivary glands, adipose tissues, thymus, lung, heart, intestines, liver, testes and skin of 2-month-old mice. JMJD3 and UTX were mostly expressed in the brain, salivary glands, adipose tissues, lung, heart, skin and testes of 7-day-old mice. No significant association was found between the distribution of H3K27me3 and the expression of EZH2. There was also no obvious inverse distribution relationship between H3K27me3 and JMJD3 or UTX. Moreover, there was no negative relationship between the distribution of EZH2, JMJD3 and UTX. These results suggest that EZH2, JMJD3 and UTX may play important roles in many tissues of mice after birth. The levels of H3K27me3 and its modified enzymes may be controlled by multiple factors in vivo to fulfill complex physiological functions.

Lymphatic absorption is a highly regulated process driven by both an extrinsic mechanism (external force) and an intrinsic mechanism (lymphatic vessel contractility). The lymphatic muscle is a specialized smooth muscle with unique mechanical properties. To understand the molecular mechanism and relative contribution of smooth muscle contraction in lymphatic absorption, we analyzed mice with a smooth muscle-specific deletion of Mylk, a critical gene for smooth muscle contraction. Interestingly, the knockout mice were significantly resistant to anesthesia reagents. Upon injection in the feet with FITC-dextran, the mutant mice displayed a 2-fold delay of the absorption peak in the peripheral circulation. Examining the ear lymphatic vessels of the mutant mice revealed a reduction in the amount of fluid in the lumens of the lymphangions, suggesting an impairment of lymph formation. The Mylk-deficient lymphatic muscle exhibited a significant reduction of peristalsis and of myosin light chain phosphorylation in response to depolarization. We thus concluded that MLCK and myosin light chain phosphorylation are required for lymphatic vessel contraction. Lymphatic contractility is not an exclusive requirement for lymphatic absorption, and external force appears to be necessary for absorption.

L-type voltage-dependent Ca(2+) channels (VDCC(L)) play an important role in the maintenance of intracellular calcium homeostasis, and influence multiple cellular processes. They have been confirmed to contribute to the functional activities of osteoblasts. Recently, VDCC(L) expression was reported in mesenchymal stem cells (MSCs), but the role of VDCC(L) in MSCs is still undetermined. The aim of this study was to determine whether VDCC(L) may be regarded as a new regulator in the proliferation and osteogenic differentiation of rat MSC (rMSCs). In this study, we examined functional Ca(2+) currents (I(Ca)) and mRNA expression of VDCC(L) in rMSCs, and then suppressed VDCC(L) using nifedipine (Nif), a VDCC(L) blocker, to investigate its role in rMSCs. The proliferation and osteogenic differentiation of MSCs were analyzed by MTT, flow cytometry, alkaline phosphatase (ALP), Alizarin Red S staining, RT-PCR, and real-time PCR assays. We found that Nif exerts antiproliferative and apoptosis-inducing effects on rMSCs. ALP activity and mineralized nodules were significantly decreased after Nif treatment. Moreover, the mRNA levels of the osteogenic markers, osteocalcin (OCN), bone sialoprotein (BSP), and runt-related transcription factor 2 (Runx2), were also down-regulated. In addition, we transfected α1C-siRNA into the cells to further confirm the role of VDCC(L) in rMSCs, and a similar effect on osteogenesis was found. These results suggest that VDCC(L) plays a crucial role in the proliferation and osteogenic differentiation of rMSCs.