In research settings, circulating tumor DNA (ctDNA) shows promise as a tumor-specific biomarker for pancreatic ductal adenocarcinoma (PDAC). This study aims to perform analytical and clinical ...validation of a
ctDNA assay in a Clinical Laboratory Improvement Amendments (CLIA) and College of American Pathology-certified clinical laboratory.
Digital-droplet PCR was used to detect the major PDAC-associated somatic
mutations (G12D, G12V, G12R, and Q61H) in liquid biopsies. For clinical validation, 290 preoperative and longitudinal postoperative plasma samples were collected from 59 patients with PDAC. The utility of ctDNA status to predict PDAC recurrence during follow-up was assessed.
ctDNA was detected preoperatively in 29 (49%) patients and was an independent predictor of decreased recurrence-free survival (RFS) and overall survival (OS). Patients who had neoadjuvant chemotherapy were less likely to have preoperative ctDNA than were chemo-naïve patients (21% vs. 69%;
< 0.001). ctDNA levels dropped significantly after tumor resection. Persistence of ctDNA in the immediate postoperative period was associated with a high rate of recurrence and poor median RFS (5 months). ctDNA detected during follow-up predicted clinical recurrence sensitivity 90% (95% confidence interval (CI), 74%-98%), specificity 88% (95% CI, 62%-98%) with a median lead time of 84 days (interquartile range, 25-146). Detection of ctDNA during postpancreatectomy follow-up was associated with a median OS of 17 months, while median OS was not yet reached at 30 months for patients without ctDNA (
= 0.011).
Measurement of
ctDNA in a CLIA laboratory setting can be used to predict recurrence and survival in patients with PDAC.
Throughout the design and development of supramolecular receptors for anion binding, many different non-covalent anion-binding motifs have been employed. One motif seen in many host-guest systems is ...the sometimes weaker, 'non-traditional' aryl CH hydrogen bond. From June Sutor's discovery of the interaction and its subsequent dismissal by the field in the 1960s to today's use of the aryl CH hydrogen bond in synthetic anion receptors, the path our lab took to begin studying this interaction has been influenced by many other researchers in the field. This feature article highlights the history and properties of the CH hydrogen bond, with a particular focus on aryl CH hydrogen bonds in anion recognition. We highlight select recent developments in the field of anion receptors utilizing aryl CH hydrogen bonds, with an emphasis on how this has influenced the evolution of our approach in designing fundamental studies on CH hydrogen bonding and exploiting this interaction in efforts aimed toward preferential anion binding.
This feature article highlights recent approaches to anion recognition with a focus on aryl CH hydrogen bonds.
There has been significant improvement in treatment outcomes of primary central nervous system lymphoma (PCNSL) at specialized centers over the past several decades; however, it is unclear if these ...changes have translated to benefits in the general population.
In this study, we utilized 2 national databases to examine survival trends over time for PCNSL: the Central Brain Tumor Registry of the United States (CBTRUS, 2000-2013) and 18 registries from the Surveillance, Epidemiology, and End Results program (SEER, 1973-2013).
The annual incidence of PCNSL in 2013 was 0.4 per 100000 population (CBTRUS/SEER). Incidence increased from 0.1 per 100000 in the 1970s to 0.4 per 100000 in the 1980s, correlating with an increase in the diagnosis of patients ≥70 years (1973: 0.2 vs 2013: 2.1 SEER). Incidence rates differed greatly between young and elderly patients (age 20-29 y: 0.08 vs 70-79 y: 4.32 CBTRUS). Even though the median overall survival of all patients doubled from 12.5 months in the 1970s to 26 months in the 2010s, this survival benefit was limited to patients <70 years. Survival in the elderly population has not changed in the last 40 years (6 mo in the 1970s vs 7 mo in the 2010s, P = 0.1).
The poor outcome seen in the particularly vulnerable elderly patient population highlights the need for clinical trials targeting the elderly in hopes of improving treatment strategies and survival.
Perinatal infection with Streptococcus agalactiae, or Group B Streptococcus (GBS), is associated with preterm birth, neonatal sepsis, and stillbirth. Here, we study the interactions of GBS with ...macrophages, essential sentinel immune cells that defend the gravid reproductive tract. Transcriptional analyses of GBS-macrophage co-cultures reveal enhanced expression of a gene encoding a putative metal resistance determinant, cadD. Deletion of cadD reduces GBS survival in macrophages, metal efflux, and resistance to metal toxicity. In a mouse model of ascending infection during pregnancy, the ΔcadD strain displays attenuated bacterial burden, inflammation, and cytokine production in gestational tissues. Furthermore, depletion of host macrophages alters cytokine expression and decreases GBS invasion in a cadD-dependent fashion. Our results indicate that GBS cadD plays an important role in metal detoxification, which promotes immune evasion and bacterial proliferation in the pregnant host.
Abstract
We present here far-infrared photometry of galaxies in a sample that is relatively unexplored at these wavelengths: low-metallicity dwarf galaxies with moderate star formation rates. Four ...dwarf irregular galaxies from the
Little Things
survey are considered, with deep Herschel PACS and SPIRE observations at 100, 160, 250, 350, and 500
μ
m. Results from modified blackbody fits indicate that these galaxies have low dust masses and cooler dust temperatures than more actively star-forming dwarfs, occupying the lowest
L
TIR
and
M
dust
regimes seen among these samples. Dust-to-gas mass ratios of ∼10
−5
are lower, overall, than in more massive and active galaxies but are roughly consistent with the broken power-law relation between the dust-to-gas ratio and metallicity found for other low-metallicity systems. Chemical evolution modeling suggests that these dwarf galaxies are likely forming very little dust via stars or grain growth and have very high dust destruction rates.
Antigen-specific CD8
T cell accumulation in tumors is a prerequisite for effective immunotherapy, and yet the mechanisms of lymphocyte transit are not well defined. Here we show that tumor-associated ...lymphatic vessels control T cell exit from tumors via the chemokine CXCL12, and intratumoral antigen encounter tunes CXCR4 expression by effector CD8
T cells. Only high-affinity antigen downregulates CXCR4 and upregulates the CXCL12 decoy receptor, ACKR3, thereby reducing CXCL12 sensitivity and promoting T cell retention. A diverse repertoire of functional tumor-specific CD8
T cells, therefore, exit the tumor, which limits the pool of CD8
T cells available to exert tumor control. CXCR4 inhibition or loss of lymphatic-specific CXCL12 boosts T cell retention and enhances tumor control. These data indicate that strategies to limit T cell egress might be an approach to boost the quantity and quality of intratumoral T cells and thereby response to immunotherapy.
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
Obesity enhances breast cancer risk in postmenopausal women and premenopausal women with genetic or familial risk factors. We have shown previously that within breast tissue, obesity increases ...macrophage-driven inflammation and promotes expansion of luminal epithelial cell populations that are hypothesized to be the cells of origin for the most common subtypes of breast cancer. However, it is not clear how these changes within the microenvironment of the breast alter cancer risk and tumor growth. Using a high-fat diet to induce obesity, we examined preneoplastic changes associated with epithelial cell-specific loss of Trp53. Obesity significantly enhanced the incidence of tumors of diverse histotypes and increased stromal cells within the tumor microenvironment. Obesity also promoted the growth of preneoplastic lesions containing elevated numbers of luminal epithelial progenitor cells, which were surrounded by macrophages. To understand how macrophage-driven inflammation due to obesity enhances tumor formation, mice were treated with IgG or anti-F4/80 antibodies to deplete macrophages during preneoplastic growth. Unexpectedly, depletion of macrophages in obese mice enhanced mammary epithelial cell stem/progenitor activity, elevated expression of estrogen receptor alpha, and increased DNA damage in cells. Together, these results suggest that in obesity, macrophages reduce epithelial cells with DNA damage, which may limit the progression of preneoplastic breast lesions, and uncovers complex macrophage function within the evolving tumor microenvironment. Understanding how obesity alters the function of macrophages during tumor formation may lead to chemoprevention options for at-risk obese women. SIGNIFICANCE: Understanding how obesity impacts early tumor growth and response to macrophage-targeted therapies may improve therapeutics for obese patients with breast cancer and identify patient populations that would benefit from macrophage-targeted therapies.
The diffuse variant of follicular lymphoma (dFL) is a rare variant of FL lacking t(14;18) that was first described in 2009. In this study, we use a comprehensive approach to define unifying ...pathologic and genetic features through gold-standard pathologic review, FISH, SNP-microarray, and next-generation sequencing of 16 cases of dFL. We found unique morphologic features, including interstitial sclerosis, microfollicle formation, and rounded nuclear cytology, confirmed absence of t(14;18) and recurrent deletion of 1p36, and showed a novel association with deletion/CN-LOH of 16p13 (inclusive of CREBBP, CIITA, and SOCS1). Mutational profiling demonstrated near-uniform mutations in CREBBP and STAT6, with clonal dominance of CREBBP, among other mutations typical of germinal-center B-cell lymphomas. Frequent CREBBP and CIITA codeletion/mutation suggested a mechanism for immune evasion, while subclonal STAT6 activating mutations with concurrent SOCS1 loss suggested a mechanism of BCL-xL/BCL2L1 upregulation in the absence of BCL2 rearrangements. A review of the literature showed significant enrichment for 16p13 and 1p36 loss/CN-LOH, STAT6 mutation, and CREBBP and STAT6 comutation in dFL, as compared with conventional FL. With this comprehensive approach, our study demonstrates confirmatory and novel genetic associations that can aid in the diagnosis and subclassification of this rare type of lymphoma.
Common wheat (Triticum aestivum L.) is a global staple crop, and insect pests can impact grain yield. The wheat stem sawfly (Cephus cinctus, WSS) is a major wheat pest, and while partial resistance ...has been deployed by breeding for a solid-stem trait, this trait is affected by environment. Here, a proteomics and metabolomics study was performed on four wheat cultivars to characterize a molecular response to WSS infestation. The cultivars Hatcher (hollow-stem partially tolerant), Conan (semisolid-stem-resistant), and Denali and Reeder (hollow-stem-susceptible) were infested with WSS, and changes in stem proteins and metabolites were characterized using liquid chromatography–mass spectrometry. The proteome was characterized as 1830 proteins that included five major biological processes, including metabolic processes and response to stimuli, and the metabolome (1823 metabolites) spanned eight chemical superclasses, including alkaloids, benzenoids, and lipids. All four varieties had a molecular response to WSS following infestation. Hatcher had the most distinct changes, whereby 62 proteins and 29 metabolites varied in metabolic pathways involving enzymatic detoxification, proteinase inhibition, and antiherbivory compound production via benzoxazinoids, neolignans, and phenolics. Taken together, these data demonstrate variation in the wheat stem molecular response to WSS infestation and support breeding for molecular resistance in hollow-stem cultivars.
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IJS, KILJ, NUK, PNG, UL, UM
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