Cell Type-specific Transcription of the α1(VI) Collagen Gene ROLE OF THE AP1 BINDING SITE AND OF THE CORE PROMOTER

Analysis of the chromatin of different cell types has identified four DNase I-hypersensitive sites in the 5′-flanking region of the α1(VI) collagen gene, mapping at −4.6, −4.4, −2.5, and −0.1 kilobase (kb) from the RNA start site. The site at −2.5 kb was independent from, whereas the other three sites could be related to, α1(VI) mRNA expression. The site at −0.1 kb was present in cells expressing (NIH3T3 and C2C12) but absent in cells not expressing (EL4) the mRNA; the remaining two sites were apparently related with high levels of mRNA. DNase I footprinting and gel-shift assays with NIH3T3 and C2C12 nuclear extracts have located a binding site for transcription factor AP1 (activator protein 1) between nucleotides −104 and −73. When nuclear extracts from EL4 lymphocytes were used, the AP1 site-containing sequence was bound by proteins not related to AP1. The existence of the hypersensitive site at −0.1 kb may be related to the binding of AP1 and of additional factors to the core promoter (Piccolo, S., Bonaldo, P., Vitale, P., Volpin, D., and Bressan, G. M. (1995) J. Biol. Chem. 270, 19583–19590). The function of the AP1 binding site and of the core promoter in the transcriptional regulation of the Col6a1gene was investigated by expressing several promoter-reporter gene constructs in transgenic mice and in cell cultures. The results indicate that regulation of transcription of the Col6a1gene by different cis-acting elements (core promoter, AP1 binding site and enhancers) is not completely modular, but the final output depends on the specific interactions among the three elements in a defined cell type

Analysis of Regulatory Regions of Emilin1 Gene and Their Combinatorial Contribution to Tissue-specific Transcription

The location of regions that regulate transcription of the murine Emilin1 gene was investigated in a DNA fragment of 16.8 kb, including the entire gene and about 8.7 and 0.6 kb of 5'- and 3'-flanking sequences, respectively. The 8.7-kb segment contains the 5'-end of the putative 2310015E02Rik gene and the sequence that separates it from Emilin1, whereas the 0.6-kb fragment covers the region between Emilin1 and Ketohexokinase genes. Sequence comparison between species identified several conserved regions in the 5'-flanking sequence. Most of them contained chromatin DNase I-hypersensitive sites, which were located at about -950 (HS1), -3100 (HS2), -4750 (HS3), and -5150 (HS4) in cells expressing Emilin1 mRNA. Emilin1 transcription initiates at multiple sites, the major of which correspond to two Initiator sequences. Promoter assays suggest that core promoter activity was mainly dependent on Initiator1 and on Sp1-binding sites close to the Initiators. Moreover, one important regulatory region was contained between -1 and -169 bp and a second one between -630 bp and -1.1 kb. The latter harbors a putative binding site for transcription factor AP1 matching the location of HS1. The function of different regions was studied by expressing lacZ constructs in transgenic mice. The results show that the 16.8-kb segment contains regulatory sequences driving high level transcription in all the tissues where Emilin1 is expressed. Moreover, the data suggest that transcription in different tissues is achieved through combinatorial cooperation between various regions, rather than being dependent on a single cis-activating region specific for each tissue

Targeting interleukin-1β protects from aortic aneurysms induced by disrupted transforming growth factor β signaling

Aortic aneurysms are life-threatening conditions with effective treatments mainly limited to emergency surgery or trans-arterial endovascular stent grafts, thus calling for the identification of specific molecular targets. Genetic studies have highlighted controversial roles of transforming growth factor β (TGF-β) signaling in aneurysm development. Here, we report on aneurysms developing in adult mice after smooth muscle cell (SMC)-specific inactivation of Smad4, an intracellular transducer of TGF-β. The results revealed that Smad4 inhibition activated interleukin-1β (IL-1β) in SMCs. This danger signal later recruited innate immunity in the adventitia through chemokine (C-C motif) ligand 2 (CCL2) and modified the mechanical properties of the aortic wall, thus favoring vessel dilation. SMC-specific Smad4 deletion in Il1r1- or Ccr2-null mice resulted in milder aortic pathology. A chronic treatment with anti-IL-1β antibody effectively hampered aneurysm development. These findings identify a mechanistic target for controlling the progression of aneurysms with compromised TGF-β signaling, such as those driven by SMAD4 mutations

Emilin-1 controls arterial blood pressure by regulating contractility of vascular smooth muscle cells

Emilin-1 is a protein of the elastic extracellular matrix (ECM) expressed in interstitial connective tissue and in the cardiovascular system. Emilin1 null mice display hypotrophic remodeling of the wall of conductance arteries and increased blood pressure. The protein regulates the bioavailability of TGF-b by inhibiting proteolysis of the proTGF-b precursor to LAP/TGF-b, a complex from which the growth factor can be subsequently released for receptor binding. In the absence of Emilin-1, the amount of active TGF-b is increased. As Emilin-1 is expressed in blood vessels starting from early stages of embryonic development to adulthood, a key question concerning the function of the protein is whether the Emilin1-/- phenotype is the result of a developmental defect or the function of the protein is required for the regulation of blood pressure and arterial structure also in the adult. The conditional gene targeting procedure chosen to inactivate the Emilin1 gene in smooth muscle cells (SMCs) of adult mice included the use of floxed Emilin1 and CreERT2 (a tamoxifen inducible Cre recombinase) under the control of the smooth muscle myosin heavy chain (Smmhc) promoter. Tamoxifen administration induced activity of Cre specifically in vascular and visceral SMCs, as revealed by X-gal staining of tissues from animals with the Rosa26R mutation. When Emilin1flox/flox mice carrying the Smmhc-CreERT2 transgene were given tamoxifen for 7 days, Emilin-1 disappeared completely in 10-12 days from start of treatment. In the same time, blood pressure increased of about 20 mmHg, a level that was stably maintained thereafter. The myogenic response of second branch meseteric arteries, evaluated using a pressure myograph, was found to be increased in Emilin1-/- mice. Additional experiments with aorta and mesenteric artery SMC cultures from control and mutant mice showed that lack of Emilin-1  enhanced phosphorylation of myosin light chain 20 when cells were stimulated with the a1-adrenergic receptor agonists phenylephrine or with angiotensin II. Moreover, basal cytosolic Ca2+ levels and calcium transients induced by stimulation with phenylephrine and angiotensin II were increased in SMCs from Emilin1-/- mutants. The data suggest that Emilin-1 expression is continuously required for regulation of blood pressure and that the increase of TGF-b activity induced by diminished Emilin-1  stimulates, likely through alteration of intracellular calcium homeostasis, contractility of vascular SMC to mechanical and chemical stimuli with ensuing hypertension

A quasar-galaxy mixing diagram: quasar spectral energy distribution shapes in the optical to near-infrared

We define a quasar-galaxy mixing diagram using the slopes of their spectral energy distributions (SEDs) from 1 \u3bcm to 3000 \uc5 and from 1 to 3 \u3bcm in the rest frame. The mixing diagram can easily distinguish among quasar-dominated, galaxy-dominated and reddening-dominated SED shapes. By studying the position of the 413 XMM-selected type 1 AGN in the wide-field `Cosmic Evolution Survey' in the mixing diagram, we find that a combination of the Elvis et al. mean quasar SED with various contributions from galaxy emission and some dust reddening is remarkably effective in describing the SED shape from 0.3 to 3 \u3bcm for large ranges of redshift, luminosity, black hole mass and Eddington ratio of type 1 AGN. In particular, the location in the mixing diagram of the highest luminosity AGN is very close (within 1\u3c3) to that of the Elvis et al. SED template. The mixing diagram can also be used to estimate the host galaxy fraction and reddening in quasar. We also show examples of some outliers which might be AGN in different evolutionary stages compared to the majority of AGN in the quasar-host galaxy co-evolution cycle

Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P < .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients

CAPSAICIN-INDUCED INHIBITION OF MITOGEN AND IL-2-STIMULATED CELL PROLIFERATION:ITS REVERSAL BY IN VIVO SUBSTANCE P ADMINISTRATION.

The direct and indirect interaction between the nervous and the immune systems was evaluated in the rat using the neurotoxin capsaicin. Capsaicin treatment of neonatal rats (50 mg/kg at 2 days of age), results in a marked inhibition of mitogen and hrIL-2-induced cell proliferation both in the spleen and peripheral blood. Inhibition is already evident on day 15 after treatment and persists until day 90 in the spleen; at this time a return to control levels is observed in peripheral blood. The inhibition of proliferative response strongly correlates with a decreased number of CD5+ and CD4+ T cells as evaluated by immunofluorescence and FACS analysis. Moreover, continuous in vivo SP administration stimulates mitogen and hrIL-2-induced proliferative response and completely reverts the capsaicin-induced inhibition of lymphocyte proliferation in the spleen