The Lineage-Defining Transcription Factors SOX2 and NKX2-1 Determine Lung Cancer Cell Fate and Shape the Tumor Immune Microenvironment.

The major types of non-small-cell lung cancer (NSCLC)-squamous cell carcinoma and adenocarcinoma-have distinct immune microenvironments. We developed a genetic model of squamous NSCLC on the basis of overexpression of the transcription factor Sox2, which specifies lung basal cell fate, and loss of the tumor suppressor Lkb1 (SL mice). SL tumors recapitulated gene-expression and immune-infiltrate features of human squamous NSCLC; such features included enrichment of tumor-associated neutrophils (TANs) and decreased expression of NKX2-1, a transcriptional regulator that specifies alveolar cell fate. In Kras-driven adenocarcinomas, mis-expression of Sox2 or loss of Nkx2-1 led to TAN recruitment. TAN recruitment involved SOX2-mediated production of the chemokine CXCL5. Deletion of Nkx2-1 in SL mice (SNL) revealed that NKX2-1 suppresses SOX2-driven squamous tumorigenesis by repressing adeno-to-squamous transdifferentiation. Depletion of TANs in SNL mice reduced squamous tumors, suggesting that TANs foster squamous cell fate. Thus, lineage-defining transcription factors determine the tumor immune microenvironment, which in turn might impact the nature of the tumor.

High risk of lung cancer in surfactant-related gene variant carriers.

BACKGROUND: Several rare surfactant-related gene (SRG) variants associated with interstitial lung disease are suspected to be associated with lung cancer, but data are missing. We aimed to study the epidemiology and phenotype of lung cancer in an international cohort of SRG variant carriers. METHODS: We conducted a cross-sectional study of all adults with SRG variants in the OrphaLung network and compared lung cancer risk with telomere-related gene (TRG) variant carriers. RESULTS: We identified 99 SRG adult variant carriers (SFTPA1 (n=18), SFTPA2 (n=31), SFTPC (n=24), ABCA3 (n=14) and NKX2-1 (n=12)), including 20 (20.2%) with lung cancer (SFTPA1 (n=7), SFTPA2 (n=8), SFTPC (n=3), NKX2-1 (n=2) and ABCA3 (n=0)). Among SRG variant carriers, the odds of lung cancer was associated with age (OR 1.04, 95% CI 1.01-1.08), smoking (OR 20.7, 95% CI 6.60-76.2) and SFTPA1/SFTPA2 variants (OR 3.97, 95% CI 1.39-13.2). Adenocarcinoma was the only histological type reported, with programmed death ligand-1 expression ≥1% in tumour cells in three samples. Cancer staging was localised (I/II) in eight (40%) individuals, locally advanced (III) in two (10%) and metastatic (IV) in 10 (50%). We found no somatic variant eligible for targeted therapy. Seven cancers were surgically removed, 10 received systemic therapy, and three received the best supportive care according to their stage and performance status. The median overall survival was 24 months, with stage I/II cancers showing better survival. We identified 233 TRG variant carriers. The comparative risk (subdistribution hazard ratio) for lung cancer in SRG patients versus TRG patients was 18.1 (95% CI 7.1-44.7). CONCLUSIONS: The high risk of lung cancer among SRG variant carriers suggests specific screening and diagnostic and therapeutic challenges. The benefit of regular computed tomography scan follow-up should be evaluated.

Adult mouse and human organoids derived from thyroid follicular cells and modeling of Graves' hyperthyroidism.

The thyroid maintains systemic homeostasis by regulating serum thyroid hormone concentrations. Here we report the establishment of three-dimensional (3D) organoids from adult thyroid tissue representing murine and human thyroid follicular cells (TFCs). The TFC organoids (TFCOs) harbor the complete machinery of hormone production as visualized by the presence of colloid in the lumen and by the presence of essential transporters and enzymes in the polarized epithelial cells that surround a central lumen. Both the established murine as human thyroid organoids express canonical thyroid markers PAX8 and NKX2.1, while the thyroid hormone precursor thyroglobulin is expressed at comparable levels to tissue. Single-cell RNA sequencing and transmission electron microscopy confirm that TFCOs phenocopy primary thyroid tissue. Thyroid hormones are readily detectable in conditioned medium of human TFCOs. We show clinically relevant responses (increased proliferation and hormone secretion) of human TFCOs toward a panel of Graves' disease patient sera, demonstrating that organoids can model human autoimmune disease.

Gastric-Type Expression Signature in Hepatocellular Carcinoma.

It is known that V-set and immunoglobulin domain containing 1 (VSIG1) is a cell-cell adhesion molecule that can serve as an indicator of better survival in patients with gastric cancer. Its interaction with cytoplasmic thyroid transcription factor 1 (TTF-1) has been hypothesized to characterize gastric-type HCC, but its clinical importance is far from understood. As VSIG1 has also been supposed to be involved in the epithelial-mesenchymal transition (EMT) phenomenon, we checked for the first time in the literature the supposed interaction between VSIG1, TTF-1, and Vimentin (VIM) in HCCs. Immunohistochemical (IHC) stains were performed on 217 paraffin-embedded tissue samples that included tumor cells and normal hepatocytes, which served as positive internal controls. VSIG1 positivity was seen in 113 cases (52.07%). In 71 out of 217 HCCs (32.71%), simultaneous positivity for VSIG1 and TTF-1 was seen, being more specific for G1/G2 carcinomas with a trabecular architecture and a longer OS (p = 0.004). A negative association with VIM was revealed (p < 0.0001). Scirrhous-type HCC proved negative for all three examined markers. The present paper validates the hypothesis of the existence of a gastric-type HCC, which shows a glandular-like architecture and is characterized by double positivity for VSIG1 and TTF-1, vimentin negativity, and a significant OS.

Regulatory effect of NK homeobox 1 (NKX2.1) on melanocortin 4 receptor (Mc4r) promoter in Mandarin fish.

The melanocortin 4 receptor (MC4R) is a G protein-coupled transporter that mediates the regulation of thyroid hormones and leptin on energy balance and food intake. However, the mechanisms of transcriptional regulation of Mc4r by thyroid hormone and leptin in fish have been rarely reported. The messenger RNA expression of Mc4r gene was significantly higher in brain than those in other tissues of mandarin fish. We analyzed the structure and function of a 2029 bp sequence of Mc4r promoter. Meanwhile, overexpression of NKX2.1 and incubation with leptin significantly increased Mc4r promoter activity, but triiodothyronine showed the opposite effect. In addition, mutations in the NKX2.1 binding site abolished not only the activation of Mc4r promoter activity by leptin but also the inhibitory effect of thyroid hormones on Mc4r promoter activity. In summary, these results suggested that thyroid hormones and leptin might regulate the transcriptional expression of Mc4r through NKX2.1.

Cortical distribution of GABAergic interneurons is determined by migration time and brain size.

Cortical interneurons (CINs) originate in the ganglionic eminences (GEs) and migrate tangentially to the cortex guided by different attractive and repulsive cues. Once inside the cortex, the cellular and molecular mechanisms determining the migration of CINs along the rostrocaudal axis are less well understood. Here, we investigated the cortical distribution of CINs originating in the medial and caudal GEs at different time points. Using molecular and genetic labeling, we showed that, in the mouse, early- and late-born CINs (E12 versus E15) are differentially distributed along the rostrocaudal axis. Specifically, late-born CINs are preferentially enriched in cortical areas closer to their respective sites of origin in the medial or caudal GE. Surprisingly, our in vitro experiments failed to show a preferential migration pattern along the rostrocaudal axis for medial- or caudal-born CINs. Moreover, in utero transplantation experiments suggested that the rostrocaudal dispersion of CINs depends on the developmental stage of the host brain and is limited by the migration time and the increasing size of the developing brain. These data suggest that the embryonic expansion of the cortex contributes to the rostrocaudal distribution of CINs.

Transcriptome analysis reveals the essential role of NK2 homeobox 1/thyroid transcription factor 1 (NKX2-1/TTF-1) in gastric adenocarcinoma of fundic-gland type.

BACKGROUND: Gastric adenocarcinoma of fundic-gland type (GA-FG) is a gastric malignancy with little relation to Helicobacter pylori. Clinical characteristics of GA-FG have been established, but molecular mechanisms leading to tumorigenesis have not yet been elucidated. METHODS: We subjected three GA-FG tumors-normal mucosa pairs to microarray analysis. Network analysis was performed for the top 30 up-regulated gene transcripts, followed by immunohistochemical staining to confirm the gene expression analysis results. AGS and NUGC4 cells were transfected with the gene-encoding NK2 homeobox 1/thyroid transcription factor 1 (NKX2-1/TTF-1) to evaluate transcriptional changes in its target genes. RESULTS: Comprehensive gene expression analysis identified 1410 up-regulated and 1395 down-regulated gene probes with ≥ two-fold difference in expression. Among the top 30 up-regulated genes in GA-FG, we identified transcription factor NKX2-1/TTF-1, a master regulator of lung/thyroid differentiation, together with surfactant protein B (SFTPB), SFTPC, and secretoglobin family 3A member 2(SCGB3A2), which are regulated by NKX2-1/TTF-1. Immunohistochemical analysis of 16 GA-FG specimens demonstrated significantly higher NKX2-1/TTF-1 and SFTPB levels, as compared to that in adjacent normal mucosa (P < 0.05), while SCGB3A2 levels did not differ (P = 0.341). Transduction of NKX2-1/TTF-1 into AGS and NUGC4 cells induced transactivation of SFTPB and SFTPC, indicating that NKX2-1/TTF-1 can function as normally in gastric cells as it can in the lung cells. CONCLUSIONS: Our first transcriptome analysis of GA-FG indicates significant expression of NKX2-1/TTF1 in GA-FG. Immunohistochemistry and cell biology show ectopic expression and normal transactivation ability of NKX2-1/TTF-1, suggesting that it plays an essential role in GA-FG development.

Transcriptional Circuitry of NKX2-1 and SOX1 Defines an Unrecognized Lineage Subtype of Small-Cell Lung Cancer.

Rationale: The current molecular classification of small-cell lung cancer (SCLC) on the basis of the expression of four lineage transcription factors still leaves its major subtype SCLC-A as a heterogeneous group, necessitating more precise characterization of lineage subclasses. Objectives: To refine the current SCLC classification with epigenomic profiles and to identify features of the redefined SCLC subtypes. Methods: We performed unsupervised clustering of epigenomic profiles on 25 SCLC cell lines. Functional significance of NKX2-1 (NK2 homeobox 1) was evaluated by cell growth, apoptosis, and xenograft using clustered regularly interspaced short palindromic repeats-Cas9 (CRISPR-associated protein 9)-mediated deletion. NKX2-1-specific cistromic profiles were determined using chromatin immunoprecipitation followed by sequencing, and its functional transcriptional partners were determined using coimmunoprecipitation followed by mass spectrometry. Rb1flox/flox; Trp53flox/flox and Rb1flox/flox; Trp53flox/flox; Nkx2-1flox/flox mouse models were engineered to explore the function of Nkx2-1 in SCLC tumorigenesis. Epigenomic landscapes of six human SCLC specimens and 20 tumors from two mouse models were characterized. Measurements and Main Results: We identified two epigenomic subclusters of the major SCLC-A subtype: SCLC-Aα and SCLC-Aσ. SCLC-Aα was characterized by the presence of a super-enhancer at the NKX2-1 locus, which was observed in human SCLC specimens and a murine SCLC model. We found that NKX2-1, a dual lung and neural lineage factor, is uniquely relevant in SCLC-Aα. In addition, we found that maintenance of this neural identity in SCLC-Aα is mediated by collaborative transcriptional activity with another neuronal transcriptional factor, SOX1 (SRY-box transcription factor 1). Conclusions: We comprehensively describe additional epigenomic heterogeneity of the major SCLC-A subtype and define the SCLC-Aα subtype by the core regulatory circuitry of NKX2-1 and SOX1 super-enhancers and their functional collaborations to maintain neuronal linage state.

Persisting embryonal infundibular recess in a case of TITF-1 gene mutation.

The thyroid transcription factor 1 (TITF-1) gene plays an important role in the development of the ventral forebrain, thyroid and lungs. Mutations of this gene are known to cause benign hereditary chorea (BHC) and can cause the full spectrum of abnormalities seen in the brain-thyroid-lung syndrome. Abnormalities of the ventral forebrain on imaging have been variably documented in the literature. Multiple previous reports describe a cystic pituitary mass, as well as duplication of the pituitary stalk and communication between an intrasellar cyst and the third ventricle. The initial MRI performed in our case was interpreted as an intrasellar cyst, but the high-resolution MRI performed later was able to resolve this as a persisting embryonal infundibular recess (PEIR), rather than the cystic pituitary mass which has previously been described. This case illustrates the role of the TITF-1 gene in the development of the pituitary and hypothalamus.

Transcriptional control of lung alveolar type 1 cell development and maintenance by NK homeobox 2-1.

The extraordinarily thin alveolar type 1 (AT1) cell constitutes nearly the entire gas exchange surface and allows passive diffusion of oxygen into the blood stream. Despite such an essential role, the transcriptional network controlling AT1 cells remains unclear. Using cell-specific knockout mouse models, genomic profiling, and 3D imaging, we found that NK homeobox 2-1 (Nkx2-1) is expressed in AT1 cells and is required for the development and maintenance of AT1 cells. Without Nkx2-1, developing AT1 cells lose 3 defining features-molecular markers, expansive morphology, and cellular quiescence-leading to alveolar simplification and lethality. NKX2-1 is also cell-autonomously required for the same 3 defining features in mature AT1 cells. Intriguingly, Nkx2-1 mutant AT1 cells activate gastrointestinal (GI) genes and form dense microvilli-like structures apically. Single-cell RNA-seq supports a linear transformation of Nkx2-1 mutant AT1 cells toward a GI fate. Whole lung ChIP-seq shows NKX2-1 binding to 68% of genes that are down-regulated upon Nkx2-1 deletion, including 93% of known AT1 genes, but near-background binding to up-regulated genes. Our results place NKX2-1 at the top of the AT1 cell transcriptional hierarchy and demonstrate remarkable plasticity of an otherwise terminally differentiated cell type.

MYB rearrangements and over-expression in T-cell acute lymphoblastic leukemia.

We investigated MYB rearrangements (MYB-R) and the levels of MYB expression, in 331 pediatric and adult patients with T-cell acute lymphoblastic leukemia (T-ALL). MYB-R were detected in 17 cases and consisted of MYB tandem duplication (tdup) (= 14) or T cell receptor beta locus (TRB)-MYB (= 3). As previously reported, TRB-MYB was found only in children (1.6%) while MYB tdup occurred in both age groups, although it was slightly more frequent in children (5.2% vs 2.8%). Shared features of MYB-R T-ALL were a non-early T-cell precursor (ETP) phenotype, a high incidence of NOTCH1/FBXW7 mutations (81%) and CDKN2AB deletions (70.5%). Moreover, they mainly belonged to HOXA (=8), NKX2-1/2-2/TLX1 (=4), and TLX3 (=3) homeobox-related subgroups. Overall, MYB-R cases had significantly higher levels of MYB expression than MYB wild type (MYB-wt) cases, although high levels of MYB were detected in ~ 30% of MYB-wt T-ALL. Consistent with the transcriptional regulatory networks, cases with high MYB expression were significantly enriched within the TAL/LMO subgroup (P = .017). Interestingly, analysis of paired diagnosis/remission samples demonstrated that a high MYB expression was restricted to the leukemic clone. Our study has indicated that different mechanisms underlie MYB deregulation in 30%-40% of T-ALL and highlighted that, MYB has potential as predictive/prognostic marker and/or target for tailored therapy.

A case of brain-lung-thyroid syndrome. / 脑-肺-ç”²çŠ¶è ºç»¼åˆå¾1例.

Brain-lung-thyroid syndrome is a rare autosomal dominant disorder. More than 100 cases have been reported worldwide, but few cases have been reported in China. In December 2018, a boy with brain-lung-thyroid syndrome, aged 3 years and 10 months, was admitted to Xiangya Hospital of Central South University due to repeated cough for more than 3 years. In infancy of the boy, psychomotor retardation, repeated cough, and hypothyroidism were found. Gene detection showed that there was c.927delc heterozygous variation in NKX2-1 gene (NM-001079668: exon3: c.927delC). The variation of this gene locus has not been reported in relevant literature so far, which indicates a new mutation. According to the above clinical manifestations and examination results, the boy was diagnosed as brain-lung-thyroid syndrome, which mainly characterized by nervous system disorders, accompanied by respiratory manifestations and hypothyroidism. The boy was treated with oral dopasehydrazine to relieve tremor and levothyroxine sodium tablets to relieve hypothyroidism. Anti-infection, atomization, rehabilitation training and other symptomatic supporting treatment were also administered. The boy's language and movement have improved, the thyroid hormone level is normal, and there are still repeated respiratory tract infections.

Npas1+-Nkx2.1+ Neurons Are an Integral Part of the Cortico-pallido-cortical Loop.

Within the basal ganglia circuit, the external globus pallidus (GPe) is critically involved in motor control. Aside from Foxp2+ neurons and ChAT+ neurons that have been established as unique neuron types, there is little consensus on the classification of GPe neurons. Properties of the remaining neuron types are poorly defined. In this study, we leverage new mouse lines, viral tools, and molecular markers to better define GPe neuron subtypes. We found that Sox6 represents a novel, defining marker for GPe neuron subtypes. Lhx6+ neurons that lack the expression of Sox6 were devoid of both parvalbumin and Npas1. This result confirms previous assertions of the existence of a unique Lhx6+ population. Neurons that arise from the Dbx1+ lineage were similarly abundant in the GPe and displayed a heterogeneous makeup. Importantly, tracing experiments revealed that Npas1+-Nkx2.1+ neurons represent the principal noncholinergic, cortically-projecting neurons. In other words, they form the pallido-cortical arm of the cortico-pallido-cortical loop. Our data further show that pyramidal-tract neurons in the cortex collateralized within the GPe, forming a closed-loop system between the two brain structures. Overall, our findings reconcile some of the discrepancies that arose from differences in techniques or the reliance on preexisting tools. Although spatial distribution and electrophysiological properties of GPe neurons reaffirm the diversification of GPe subtypes, statistical analyses strongly support the notion that these neuron subtypes can be categorized under the two principal neuron classes: PV+ neurons and Npas1+ neurons.SIGNIFICANCE STATEMENT The poor understanding of the neuronal composition in the external globus pallidus (GPe) undermines our ability to interrogate its precise behavioral and disease involvements. In this study, 12 different genetic crosses were used, hundreds of neurons were electrophysiologically characterized, and >100,000 neurons were histologically- and/or anatomically-profiled. Our current study further establishes the segregation of GPe neuron classes and illustrates the complexity of GPe neurons in adult mice. Our results support the idea that Npas1+-Nkx2.1+ neurons are a distinct GPe neuron subclass. By providing a detailed analysis of the organization of the cortico-pallidal-cortical projection, our findings establish the cellular and circuit substrates that can be important for motor function and dysfunction.

Conditional Ror1 knockout reveals crucial involvement in lung adenocarcinoma development and identifies novel HIF-1α regulator.

We previously reported that ROR1 is a crucial downstream gene for the TTF-1/NKX2-1 lineage-survival oncogene in lung adenocarcinoma, while others have found altered expression of ROR1 in multiple cancer types. Accumulated evidence therefore indicates ROR1 as an attractive molecular target, though it has yet to be determined whether targeting Ror1 can inhibit tumor development and growth in vivo. To this end, genetically engineered mice carrying homozygously floxed Ror1 alleles and an SP-C promoter-driven human mutant EGFR transgene were generated. Ror1 ablation resulted in marked retardation of tumor development and progression in association with reduced malignant characteristics and significantly better survival. Interestingly, gene set enrichment analysis identified a hypoxia-induced gene set (HALLMARK_HYPOXIA) as most significantly downregulated by Ror1 ablation in vivo, which led to findings showing that ROR1 knockdown diminished HIF-1α expression under normoxia and clearly hampered HIF-1α induction in response to hypoxia in human lung adenocarcinoma cell lines. The present results directly demonstrate the importance of Ror1 for in vivo development and progression of lung adenocarcinoma, and also identify Ror1 as a novel regulator of Hif-1α. Thus, a future study aimed at the development of a novel therapeutic targeting ROR1 for treatment of solid tumors such as seen in lung cancer, which are frequently accompanied with a hypoxic tumor microenvironment, is warranted.

Histological characteristics of lung adenocarcinoma with uncommon actionable alterations: special emphasis on MET exon 14 skipping alterations.

AIMS: In the evolving era of precision medicine, increasing emphasis is placed on detecting molecular alterations driving the development of specific cancers and targeting them with matched therapies that can yield the best outcomes for patients. Lung adenocarcinomas with uncommon actionable alterations, including MET exon 14 skipping (METex14), ERBB2 and BRAF mutations, are rare and poorly characterised cancers. METHODS AND RESULTS: To more clearly understand the histopathological features of lung adenocarcinoma with uncommon actionable alterations, we compared the histological features of 678 cases with mitogenic driver alterations from 996 surgically resected lung adenocarcinomas. Genomic data from our cohort revealed METex14, ERBB2 and BRAF mutations in 13, 16 and 15 cases, respectively. Patients who had lung adenocarcinoma with METex14 were often elderly females. Histological features such as clear cell features (23%), hyaline globules (31%) and nuclear pleomorphism (39%) were the most frequently identified in METex14-positive cases; among those, three cases (23%) had tumour cells with bizarre giant or multilobulated nuclei. Additionally, the micropapillary pattern was the most frequently identified in ERBB2-mutated lung adenocarcinoma (31%). Lung adenocarcinoma with BRAF mutations tended to be less invasive, and the BRAF V600E mutation was identified in only one case with lepidic adenocarcinoma. Immunohistochemically, all METex14, ERBB2 and BRAF-positive tumours, except for invasive mucinous adenocarcinoma, were positive for thyroid transcription factor 1 (TTF-1). CONCLUSIONS: Our data from Japanese patients showed that lung adenocarcinoma with METex14 had unique clinicopathological characteristics: tumour cells with marked nuclear pleomorphism, hyaline globules and expression of TTF-1 in elderly women who never or lightly smoked.

Downregulation of TTF1 in the rat hypothalamic ARC or AVPV nucleus inhibits Kiss1 and GnRH expression, leading to puberty delay.

BACKGROUND: TTF1 is a transcription factor that is expressed in the hypothalamus after birth and plays crucial roles in pubertal development. TTF1 may regulate the expression of the Kiss1 gene, which may drive puberty onset in the hypothalamic arcuate (ARC) and anterior ventral paraventricular (AVPV) nuclei. METHODS: A dual-luciferase reporter assay was used to detect binding between TTF1 and the Kiss1 gene promoter. To investigate the effects of TTF1, we modified TTF1 expression in cell lines and in the ARC or AVPV nucleus of 21-day-old female rats via lentivirus infection. TTF1 and other puberty onset-related genes were detected by qRT-PCR and western blot analyses. RESULTS: The in vitro data indicated that TTF1 knockdown (KD) significantly reduced Kiss1 and GnRH expression. Overexpression (OE) of TTF1 promoted Kiss1 expression. In vivo, the expression of Kiss1 and GnRH decreased significantly in the rats with hypothalamic ARC- or AVPV-specific TTF1 KD. The TTF1-KD rats showed vaginal opening delay. H&E staining revealed that the corpus luteum was obviously reduced at the early puberty and adult stages in the rats with ARC- or AVPV-specific TTF1 KD. CONCLUSION: TTF1 bound to the promoter of the Kiss1 gene and enhanced its expression. For 21-day-old female rats, decreased TTF1 in the hypothalamic ARC or AVPV nucleus resulted in delayed vaginal opening and ovarian abnormalities. These observations suggested that TTF1 regulates puberty onset by promoting the expression of Kiss1 and plays an important role in gonad development.

Bioinformatics analysis of differentially expressed miRNAs in non-small cell lung cancer.

OBJECTIVE: Non-small cell lung cancer (NSCLC) contains 85% of lung cancer. Lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) are the largest NSCLC subgroups. The aim of the study was to investigate the underlying mechanism in developing more effective subtype-specific molecular therapeutic procedures. METHODS: A total of 876 specimens were used in this study: 494 LUAD tissues (ie, 449 LUAD tissues and 45 matched normal tissues) and 382 LUSC tissues (ie, 337 LUSC tissues and 45 matched normal tissues). The miRNA sequencing data were processed using R. The differential expressed miRNAs between lung cancer and normal tissues were analyzed using the limma package in R. Gene expression, Western blotting, hematoxylin and eosin staining, and luciferase assay were used to test LUAD and LUSC. RESULTS: LUAD and LUSC appear sharply distinct at molecular and pathological level. Let-7a-5p, miR-338, miR-375, miR-217, miR-627, miR-140, miR-147b, miR-138-2, miR-584, and miR-197 are top 10 relevant miRNAs and CLDN3, DSG3, KRT17, TMEM125, KRT5, NKX2-1, KRT7, ABCC5, KRAS, and PLCG2 are top 10 relevant genes in NSCLC. At the same time, the miRNAs expression levels were also quite different between the two groups. Among the differential expressed miRNAs, let-7a-5p was significantly down-regulated in LUAD while miR-338 was markedly down-regulated in LUSC. Bioinformatics analyses appeared that let-7a-5p directly targets high-molecular weight keratin 5 (KRT5) which were shown to be a strong risk factor for LUAD. And NK2 homeobox 1(NKX2-1) which was associated with tumor progression in LUSC was identified as a target gene of miR-338. CONCLUSIONS: Distinct profile of miRNAs can take a part in the development of LUAD and LUSC and thus could serve as a subtype-specific molecular therapeutic target to protect against LUAD and LUSC.

MUC5AC enhances tumor heterogeneity in lung adenocarcinoma with mucin production and is associated with poor prognosis.

OBJECTIVE: The clinicopathological significance of Mucin5AC (MUC5AC) in lung adenocarcinoma with mucin production is still unclear. This study aimed to explore MUC5AC expression in lung adenocarcinoma with mucin production and its correlation with histological subtypes, common driver mutations and its impact on prognosis. METHODS: MUC5AC and thyroid transcription factor 1 immunohistochemistry was performed on surgical samples from 90 patients with lung adenocarcinoma with mucin production. Common driver mutations including EGFR and KRAS mutations and ALK rearrangement were detected by established methods. RESULTS: MUC5AC was significantly associated with lymphovascular invasion (P = 0.023) and tumors with intra-cytoplasmic mucin (P < 0.001). Moreover, MUC5AC was more significant in invasive mucinous adenocarcinoma (P < 0.001), as well as in tumors with KRAS mutations (P = 0.005) and a lack of thyroid transcription factor 1 expression (P < 0.001). Conversely, MUC5AC was less significantly detected in acinar predominant adenocarcinoma (P = 0.036) and tumors with EGFR mutations (P = 0.001). Notably, MUC5AC in non-pure mucinous subtype of lung adenocarcinoma with mucin production showed more aggressive behavior, distinct expression pattern and a lack of significant correlation with thyroid transcription factor 1 (P = 0.113) when compared with pure mucinous subtype. MUC5AC-positive tumors were significantly associated with a worse prognosis compared to MUC5AC-negative tumors (P < 0.001). A multivariate survival analysis showed that MUC5AC was an independent prognosis factor for poor prognosis (P = 0.006). CONCLUSIONS: The clinicopathological features of non-pure mucinous subtype of lung adenocarcinoma with mucin production were distinct and should be distinguished from pure mucinous subtype. MUC5AC was associated with poor prognosis and could be a potential therapeutic target for this distinct type of lung adenocarcinoma that has few effective treatments.

Nkx2.1 downregulation is involved in brain abnormality induced by excess retinoic acid.

Abnormal development of central nervous system (CNS) caused by neural tube defects is not only a major contributor in the prevalence of stillbirths and neonatal deaths but also causes lifelong physical disability in surviving infants. Due to insufficient known investigated causes, CNS developmental abnormality has brought sever burden on health around the world. From previous results of high throughput transcriptome sequencing, we selected transcription factor Nkx2.1 as a candidate to investigate its role on brain abnormalities induced by excessive retinoic acid. The result of in situ hybridization showed that Nkx2.1 was mainly expressed in mouse brain. After the Nkx2.1 gene was silenced, retarded proliferation and accelerated apoptosis were found in mouse Neuro-2a (N2a) cells. Furthermore, our results indicated that the main components of sonic hedgehog (Shh) signaling pathway were affected in Nkx2.1-silenced cells, implying that Nkx2.1 plays an important role in the development of mouse brain by regulating Shh signaling pathway.

Regulatory networks specifying cortical interneurons from human embryonic stem cells reveal roles for CHD2 in interneuron development.

Cortical interneurons (cINs) modulate excitatory neuronal activity by providing local inhibition. During fetal development, several cIN subtypes derive from the medial ganglionic eminence (MGE), a transient ventral telencephalic structure. While altered cIN development contributes to neurodevelopmental disorders, the inaccessibility of human fetal brain tissue during development has hampered efforts to define molecular networks controlling this process. Here, we modified protocols for directed differentiation of human embryonic stem cells, obtaining efficient, accelerated production of MGE-like progenitors and MGE-derived cIN subtypes with the expected electrophysiological properties. We defined transcriptome changes accompanying this process and integrated these data with direct transcriptional targets of NKX2-1, a transcription factor controlling MGE specification. This analysis defined NKX2-1-associated genes with enriched expression during MGE specification and cIN differentiation, including known and previously unreported transcription factor targets with likely roles in MGE specification, and other target classes regulating cIN migration and function. NKX2-1-associated peaks were enriched for consensus binding motifs for NKX2-1, LHX, and SOX transcription factors, suggesting roles in coregulating MGE gene expression. Among the NKX2-1 direct target genes with cIN-enriched expression was CHD2, which encodes a chromatin remodeling protein mutated to cause human epilepsies. Accordingly, CHD2 deficiency impaired cIN specification and altered later electrophysiological function, while CHD2 coassociated with NKX2-1 at cis-regulatory elements and was required for their transactivation by NKX2-1 in MGE-like progenitors. This analysis identified several aspects of gene-regulatory networks underlying human MGE specification and suggested mechanisms by which NKX2-1 acts with chromatin remodeling activities to regulate gene expression programs underlying cIN development.