Pleiotropic effects of FGFR1 on cell proliferation, survival, and migration in a 3D mammary epithelial cell model

Members of the fibroblast growth factor (FGF) family and the FGF receptors (FGFRs) have been implicated in mediating various aspects of mammary gland development and transformation. To elucidate the molecular mechanisms of FGFR1 action in a context that mimics polarized epithelial cells, we have developed an in vitro three-dimensional HC11 mouse mammary epithelial cell culture model expressing a drug-inducible FGFR1 (iFGFR1). Using this conditional model, iFGFR1 activation in these growth-arrested and polarized mammary acini initially led to reinitiation of cell proliferation, increased survival of luminal cells, and loss of cell polarity, resulting in the disruption of acinar structures characterized by the absence of an empty lumen. iFGFR1 activation also resulted in a gain of invasive properties and the induction of matrix metalloproteinase 3 (MMP-3), causing the cleavage of E-cadherin and increased expression of smooth muscle actin and vimentin. The addition of a pan MMP inhibitor abolished these phenotypes but did not prevent the effects of iFGFR1 on cell proliferation or survival

Evidence for a Novel Endometrioid Carcinogenic Sequence in the Fallopian Tube With Unique Beta-Catenin Expression

Epithelial proliferations in the fallopian tube have been characterized by some as stem cell outgrowths (SCOUTs) and divided into type I and type II. Type II SCOUTs exhibit diffuse cellular beta-catenin nuclear staining (β-catenin+), implying a CTNNB1 mutation. SCOUTs are more common in perimenopausal and postmenopausal women and are associated with ovarian cancer but have not been linked directly to malignancy. We analyzed type II SCOUTs in various gynecologic conditions, and searched for endometrioid atypical hyperplasias (tubal endometrioid intraepithelial neoplasia) or adenocarcinomas in the tube. β-catenin+ SCOUT frequency in cases of neoplasia was 66.7% per case and 30.7% per nonfimbrial cross-section for uterine endometrioid carcinomas versus 25% and 13.3% for controls, respectively (P=0.02 and 0.09). Multiple (3 or more) β-catenin+ SCOUTs in a single section were uncommon; 6 of 9 were associated with a carcinoma or proliferative lesion in the endometrium. Tubal endometrioid intraepithelial neoplasia/atypical hyperplasia displayed complex growth, including focal cribriform growth patterns and squamous morules. Two cases of type II SCOUTs associated with tubal endometrioid intraepithelial neoplasia/atypical hyperplasia and/or adenocarcinomas in the fallopian tube were identified, both of which coexisted with a separate endometrioid adenocarcinoma, one with bilateral ovarian endometrioid adenocarcinomas. Both benign and neoplastic tubal lesions were β-catenin+. This report is the first to link components of a unique β-catenin+ endometrioid carcinogenic sequence in the fallopian tube. It further emphasizes the multifocal nature of endometrioid neoplasia in the female genital tract and poses questions regarding the frequency and biologic underpinnings of β-catenin+ proliferations in the oviduct

Inflammatory Activity of Epithelial Stem Cell Variants from Cystic Fibrosis Lungs Is Not Resolved by CFTR Modulators

Rationale CFTR (cystic fibrosis transmembrane conductance regulator) modulator drugs restore function to mutant channels in patients with cystic fibrosis (CF) and lead to improvements in body mass index and lung function. Although it is anticipated that early childhood treatment with CFTR modulators will significantly delay or even prevent the onset of advanced lung disease, lung neutrophils and inflammatory cytokines remain high in patients with CF with established lung disease despite modulator therapy, underscoring the need to identify and ultimately target the sources of this inflammation in CF lungs. Objectives To determine whether CF lungs, like chronic obstructive pulmonary disease (COPD) lungs, harbor potentially pathogenic stem cell “variants” distinct from the normal p63/Krt5 lung stem cells devoted to alveolar fates, to identify specific variants that might contribute to the inflammatory state of CF lungs, and to assess the impact of CFTR genetic complementation or CFTR modulators on the inflammatory variants identified herein. Methods Stem cell cloning technology developed to resolve pathogenic stem cell heterogeneity in COPD and idiopathic pulmonary fibrosis lungs was applied to end-stage lungs of patients with CF (three homozygous CFTR:F508D, one CFTR F508D/L1254X; FEV1, 14–30%) undergoing therapeutic lung transplantation. Single-cell–derived clones corresponding to the six stem cell clusters resolved by single-cell RNA sequencing of these libraries were assessed by RNA sequencing and xenografting to monitor inflammation, fibrosis, and mucin secretion. The impact of CFTR activity on these variants after CFTR gene complementation or exposure to CFTR modulators was assessed by molecular and functional studies. Measurements and Main Results End-stage CF lungs display a stem cell heterogeneity marked by five predominant variants in addition to the normal lung stem cell, of which three are proinflammatory both at the level of gene expression and their ability to drive neutrophilic inflammation in xenografts in immunodeficient mice. The proinflammatory functions of these three variants were unallayed by genetic or pharmacological restoration of CFTR activity. Conclusions The emergence of three proinflammatory stem cell variants in CF lungs may contribute to the persistence of lung inflammation in patients with CF with advanced disease undergoing CFTR modulator therapy

Cloning a Profibrotic Stem Cell Variant in Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive, irreversible, and rapidly fatal interstitial lung disease marked by the replacement of lung alveoli with dense fibrotic matrices. Although the mechanisms initiating IPF remain unclear, rare and common alleles of genes expressed in lung epithelia, combined with aging, contribute to the risk for this condition. Consistently, single-cell RNA sequencing (scRNA-seq) studies have identified lung basal cell heterogeneity in IPF that might be pathogenic. We used single-cell cloning technologies to generate libraries of basal stem cells from the distal lungs of 16 patients with IPF and 10 controls. We identified a major stem cell variant that was distinguished from normal stem cells by its ability to transform normal lung fibroblasts into pathogenic myofibroblasts in vitro and to activate and recruit myofibroblasts in clonal xenografts. This profibrotic stem cell variant, which was shown to preexist in low quantities in normal and even fetal lungs, expressed a broad network of genes implicated in organ fibrosis and showed overlap in gene expression with abnormal epithelial signatures identified in previously published scRNA-seq studies of IPF. Drug screens highlighted specific vulnerabilities of this profibrotic variant to inhibitors of epidermal growth factor and mammalian target of rapamycin signaling as prospective therapeutic targets. This profibrotic stem cell variant in IPF was distinct from recently identified profibrotic stem cell variants in chronic obstructive pulmonary disease and may extend the notion that inappropriate accrual of minor and preexisting stem cell variants contributes to chronic lung conditions

A Randomized Controlled Trial of Chinese Medicine on Nonmotor Symptoms in Parkinson’s Disease

Nonmotor symptoms (NMS) of Parkinson’s disease (PD) have devastating impacts on both patients and their caregivers. Jiawei-Liujunzi Tang (JLT) has been used to treat some NMS of PD based on the Chinese medicine theory since Qing dynasty. Here we report a double-blind, randomized, placebo-controlled, add-on clinical trial aiming at evaluating the efficacy and safety of the JLT in treating NMS in PD patients. We randomly assigned 111 patients with idiopathic PD to receive either JLT or placebo for 32 weeks. Outcome measures were baseline to week 32 changes in Movement Disorder Society-Sponsored Revision of Unified PD Rating Scale (MDS-UPDRS) Parts I–IV and in NMS assessment scale for PD (NMSS). We observed improvements in the NMSS total score (p=0.019), mood/cognition (p=0.005), and reduction in hallucinations (p=0.024). In addition, post hoc analysis showed a significant reduction in constipation (p<0.001). However, there was no evidence of improvement in MDS-UPDRS Part I total score (p=0.216) at week 32. Adverse events (AEs) were mild and comparable between the two groups. In conclusion, long-term administration of JLT is well tolerated and shows significant benefits in improving NMS including mood, cognition, and constipation

MS4a4B, a CD20 Homologue in T Cells, Inhibits T Cell Propagation by Modulation of Cell Cycle

MS4a4B, a CD20 homologue in T cells, is a novel member of the MS4A gene family in mice. The MS4A family includes CD20, FcεRIβ, HTm4 and at least 26 novel members that are characterized by their structural features: with four membrane-spanning domains, two extracellular domains and two cytoplasmic regions. CD20, FcεRIβ and HTm4 have been found to function in B cells, mast cells and hematopoietic cells respectively. However, little is known about the function of MS4a4B in T cell regulation. We demonstrate here that MS4a4B negatively regulates mouse T cell proliferation. MS4a4B is highly expressed in primary T cells, natural killer cells (NK) and some T cell lines. But its expression in all malignant T cells, including thymoma and T hybridoma tested, was silenced. Interestingly, its expression was regulated during T cell activation. Viral vector-driven overexpression of MS4a4B in primary T cells and EL4 thymoma cells reduced cell proliferation. In contrast, knockdown of MS4a4B accelerated T cell proliferation. Cell cycle analysis showed that MS4a4B regulated T cell proliferation by inhibiting entry of the cells into S-G2/M phase. MS4a4B-mediated inhibition of cell cycle was correlated with upregulation of Cdk inhibitory proteins and decreased levels of Cdk2 activity, subsequently leading to inhibition of cell cycle progression. Our data indicate that MS4a4B negatively regulates T cell proliferation. MS4a4B, therefore, may serve as a modulator in the negative-feedback regulatory loop of activated T cell

Cloning and variation of ground state intestinal stem cells

Stem cells of the gastrointestinal tract, pancreas, liver, and other columnar epithelia collectively resist cloning in their elemental states. Here we demonstrate the cloning and propagation of highly clonogenic, “ground state” stem cells of the human intestine and colon. We show that derived stem cell pedigrees sustain limited copy number and sequence variation despite extensive serial passaging and display exquisitely precise, cell-autonomous commitment to epithelial differentiation consistent with their origins along the intestinal tract. This developmentally patterned and epigenetically maintained commitment of stem cells likely enforces the functional specificity of the adult intestinal tract. Using clonally-derived colonic epithelia, we show that toxins A or B of the enteric pathogen C. difficile recapitulate the salient features of pseudomembranous colitis. The stability of the epigenetic commitment programs of these stem cells, coupled with their unlimited replicative expansion and maintained clonogenicity, suggests certain advantages for their use in disease modeling and regenerative medicine

Molecular Mechanisms Associated with Nicotine Pharmacology and Dependence.

Tobacco dependence is a leading cause of preventable disease and death worldwide. Nicotine, the main psychoactive component in tobacco cigarettes, has also been garnering increased popularity in its vaporized form, as derived from e-cigarette devices. Thus, an understanding of the molecular mechanisms underlying nicotine pharmacology and dependence is required to ascertain novel approaches to treat drug dependence. In this chapter, we review the field's current understanding of nicotine's actions in the brain, the neurocircuitry underlying drug dependence, factors that modulate the function of nicotinic acetylcholine receptors, and the role of specific genes in mitigating the vulnerability to develop nicotine dependence. In addition to nicotine's direct actions in the brain, other constituents in nicotine and tobacco products have also been found to alter drug use, and thus, evidence is provided to highlight this issue. Finally, currently available pharmacotherapeutic strategies are discussed, along with an outlook for future therapeutic directions to achieve to the goal of long-term nicotine cessation