Noninvasive Papillary Urothelial Carcinoma of the Bladder: An Institutional Experience Focusing on Tumors With Borderline Features.

CONTEXT.­: Noninvasive papillary urothelial carcinomas (PUCs) comprise most urinary bladder tumors. Distinction between low-grade (LG-PUC) and high-grade (HG-PUC) PUCs is pivotal for determining prognosis and subsequent treatment. OBJECTIVE.­: To investigate the histologic characteristics of tumors with borderline features between LG-PUC and HG-PUC, focusing on the risk of recurrence and progression. DESIGN.­: We reviewed the clinicopathologic parameters of noninvasive PUC. Tumors with borderline features were subcategorized as follows: tumors that look like LG-PUC but have occasional pleomorphic nuclei (1-BORD-NUP) or elevated mitotic count (2-BORD-MIT), and tumors with side-by-side distinct LG-PUC and less than 50% HG-PUC (3-BORD-MIXED). Recurrence-free, total progression-free, and specific invasion-free survival curves were derived from the Kaplan-Meier method, and Cox regression analysis was performed. RESULTS.­: A total of 138 patients with noninvasive PUC were included, with the following distribution: LG-PUC (n = 52; 38%), HG-PUC (n = 34; 25%), BORD-NUP (n = 21; 15%), BORD-MIT (n = 14; 10%), and BORD-MIXED (n = 17; 12%). Median (interquartile range) follow-up was 44.2 months (29.9-73.1 months). Invasion-free survival was different between the 5 groups (P = .004), and pairwise comparison showed that HG-PUC had a worse prognosis compared with LG-PUC (P ≤ .001). On univariate Cox analysis, HG-PUC and BORD-NUP were 10.5 times (95% CI, 2.3-48.3; P = .003) and 5.9 times (95% CI, 1.1-31.9; P = .04) more likely to invade, respectively, when compared to LG-PUC. CONCLUSIONS.­: Our findings confirm a continuous spectrum of histologic changes in PUC. Approximately a third of noninvasive PUCs show borderline features between LG-PUC and HG-PUC. Compared with LG-PUC, BORD-NUP and HG-PUC were more likely to invade on follow-up. BORD-MIXED tumors did not statistically behave differently from LG-PUC.

Respiratory Failure Due to Idiopathic Pneumonia Syndrome in a Pediatric Patient After Recipient-derived Allogeneic Chimeric Antigen Receptor T-Cell Therapy.

Idiopathic pneumonia syndrome (IPS) is a life-threatening complication of hematopoietic cell transplantation, but it is not clearly described following chimeric antigen receptor (CAR) T-cell therapy. We describe a child who developed IPS after receiving tisagenlecleucel for post-hematopoietic cell transplantation relapsed acute lymphoblastic leukemia and had a remarkable improvement after treatment with corticosteroids and etanercept. We discuss the implications of cytokine signaling in IPS and immunologic considerations of allogeneic CAR T cells. We anticipate that the incidence of IPS and other allogeneic phenomena will be observed more often as allogeneic CAR T cells are employed in more varied settings with more mismatched donors.

Benign fibrous histiocytoma of the medial rectus muscle.

We report the case of a healthy 17-year-old girl who underwent surgery for excision of a painless, rapidly enlarging subconjunctival mass. The mass was found to be tightly adherent to the medial rectus muscle of the left eye, requiring extensive dissection. Histopathology revealed a mass of bland and foamy spindle cells in a storiform pattern that was positive for CD68, PGM1, and factor XIIIA and negative for S-100. The clinical and histopathologic findings are consistent with benign fibrous histiocytoma.

Loss-of-function of Endothelin receptor type A results in Oro-Oto-Cardiac syndrome.

Craniofacial morphogenesis is regulated in part by signaling from the Endothelin receptor type A (EDNRA). Pathogenic variants in EDNRA signaling pathway components EDNRA, GNAI3, PCLB4, and EDN1 cause Mandibulofacial Dysostosis with Alopecia (MFDA), Auriculocondylar syndrome (ARCND) 1, 2, and 3, respectively. However, cardiovascular development is normal in MFDA and ARCND individuals, unlike Ednra knockout mice. One explanation may be that partial EDNRA signaling remains in MFDA and ARCND, as mice with reduced, but not absent, EDNRA signaling also lack a cardiovascular phenotype. Here we report an individual with craniofacial and cardiovascular malformations mimicking the Ednra -/- mouse phenotype, including a distinctive micrognathia with microstomia and a hypoplastic aortic arch. Exome sequencing found a novel homozygous missense variant in EDNRA (c.1142A>C; p.Q381P). Bioluminescence resonance energy transfer assays revealed that this amino acid substitution in helix 8 of EDNRA prevents recruitment of G proteins to the receptor, abrogating subsequent receptor activation by its ligand, Endothelin-1. This homozygous variant is thus the first reported loss-of-function EDNRA allele, resulting in a syndrome we have named Oro-Oto-Cardiac Syndrome. Further, our results illustrate that EDNRA signaling is required for both normal human craniofacial and cardiovascular development, and that limited EDNRA signaling is likely retained in ARCND and MFDA individuals. This work illustrates a straightforward approach to identifying the functional consequence of novel genetic variants in signaling molecules associated with malformation syndromes.

PAX8 and PAX2 immunostaining facilitates the diagnosis of primary epithelial neoplasms of the male genital tract.

PAX8 and PAX2 are cell-lineage-specific transcription factors that are essential for the development of Wolffian and Müllerian ducts and have recently emerged as specific diagnostic markers for tumors of renal or Müllerian origin. Little is known about their expression in the Wolffian duct-derived human male genital tract. We report our findings of PAX8 and PAX2 expression in the epithelium of the normal male genital tract and in epithelial tumors derived therefrom using immunohistochemistry (IHC). We found that PAX8 and PAX2 were expressed in the epithelium of the male genital tract from the rete testis to the ejaculatory duct. Rare glands in the prostatic central zone, a tissue of purported Wolffian duct origin, were focally positive for PAX2, but no PAX8 was detected in this area, a finding that may warrant further study. We found diffuse expression of PAX8 and PAX2 in 1 case each of serous cystadenoma of the epididymis, carcinoma of the rete testis, Wolffian adnexal tumor of the seminal vesicle, and endometrioid carcinoma of the seminal vesicle. Neither PAX8 nor PAX2 was detected in the seminiferous tubules and interstitium of the normal testis, nor in Leydig cell tumors (n=6), Sertoli cell tumors (n=2), or 48 of 49 germ cell tumors. One pediatric yolk sac tumor showed focal and weak staining for PAX8. Tumors of mesothelial origin, that is, adenomatoid tumors (n=3) and peritoneal malignant mesotheliomas (n=37) in men, were negative for PAX2 and PAX8. Neither PAX2 nor PAX8 was present in other areas of the prostate. Expression of PAX8 and PAX2 in these primary epithelial neoplasms of the male genital tract is due to their histogenetic relationship with Wolffian or Müllerian ducts. PAX8 and PAX2 IHC may facilitate the diagnosis of these tumors and should be included in the differential diagnostic IHC panel.

Neonatal diabetes and congenital malabsorptive diarrhea attributable to a novel mutation in the human neurogenin-3 gene coding sequence.

OBJECTIVE: The aim was to describe the clinical presentation and to characterize the genetic mutation present in a child with congenital malabsorptive diarrhea and neonatal diabetes. RESEARCH DESIGN AND METHODS: Clinical data were obtained from chart review. Histopathological characterization of intestinal samples and neurogenin-3 (NEUROG3) sequencing were performed. Expression and function of the mutated NEUROG3 protein were assessed by Western blot analysis and luciferase reporter assay. RESULTS: At birth, the proband was small for gestational age. She presented for evaluation with persistent diarrhea and a poor postnatal growth pattern. Although the pancreas was present, serum amylase and fecal elastase levels were decreased, and blood glucose levels were persistently elevated by 5 months of age. Immunostaining of a small intestine biopsy for chromogranin A demonstrated complete absence of neuroendocrine cells. Genetic analysis revealed a nonsense mutation (E123X) in the region encoding helix II of the NEUROG3 gene, leading to premature termination at amino acid 123. The mutated truncated NEUROG3 protein was identified by Western blot analysis. Reporter assays show decreased transactivation of the NEUROD1 promoter by mutant NEUROG3 protein as compared to wild type. CONCLUSIONS: This report describes a newly identified nonsense mutation in human NEUROG3 that in the homozygous state is associated with neonatal diabetes and malabsorptive diarrhea.

The diabetes gene Pdx1 regulates the transcriptional network of pancreatic endocrine progenitor cells in mice.

Heterozygous mutations in the gene encoding the pancreatic homeodomain transcription factor pancreatic duodenal homeobox 1 (PDX1) are associated with maturity onset diabetes of the young, type 4 (MODY4) and type 2 diabetes. Pdx1 governs the early embryonic development of the pancreas and the later differentiation of the insulin-producing islet beta cells of the endocrine compartment. We derived a Pdx1 hypomorphic allele that reveals a role for Pdx1 in the specification of endocrine progenitors. Mice homozygous for this allele displayed a selective reduction in endocrine lineages associated with decreased numbers of endocrine progenitors and a marked reduction in levels of mRNA encoding the proendocrine transcription factor neurogenin 3 (Ngn3). During development, Pdx1 occupies an evolutionarily conserved enhancer region of Ngn3 and interacts with the transcription factor one cut homeobox 1 (Hnf6) to activate this enhancer. Furthermore, mRNA levels of all 4 members of the transcription factor network that regulates Ngn3 expression, SRY-box containing gene 9 (Sox9), Hnf6, Hnf1b, and forkhead box A2 (Foxa2), were decreased in homozygous mice. Pdx1 also occupied regulatory sequences in Foxa2 and Hnf1b. Thus, Pdx1 contributes to specification of endocrine progenitors both by regulating expression of Ngn3 directly and by participating in a cross-regulatory transcription factor network during early pancreas development. These results provide insights that may be applicable to beta cell replacement strategies involving the guided differentiation of ES cells or other progenitor cell types into the beta cell lineage, and they suggest a molecular mechanism whereby human PDX1 mutations cause diabetes.

On the origin of the beta cell.

The major forms of diabetes are characterized by pancreatic islet beta-cell dysfunction and decreased beta-cell numbers, raising hope for cell replacement therapy. Although human islet transplantation is a cell-based therapy under clinical investigation for the treatment of type 1 diabetes, the limited availability of human cadaveric islets for transplantation will preclude its widespread therapeutic application. The result has been an intense focus on the development of alternate sources of beta cells, such as through the guided differentiation of stem or precursor cell populations or the transdifferentiation of more plentiful mature cell populations. Realizing the potential for cell-based therapies, however, requires a thorough understanding of pancreas development and beta-cell formation. Pancreas development is coordinated by a complex interplay of signaling pathways and transcription factors that determine early pancreatic specification as well as the later differentiation of exocrine and endocrine lineages. This review describes the current knowledge of these factors as they relate specifically to the emergence of endocrine beta cells from pancreatic endoderm. Current therapeutic efforts to generate insulin-producing beta-like cells from embryonic stem cells have already capitalized on recent advances in our understanding of the embryonic signals and transcription factors that dictate lineage specification and will most certainly be further enhanced by a continuing emphasis on the identification of novel factors and regulatory relationships.

Preexisting pancreatic acinar cells contribute to acinar cell, but not islet beta cell, regeneration.

It has been suggested that pancreatic acinar cells can serve as progenitors for pancreatic islets, a concept with substantial implications for therapeutic efforts to increase insulin-producing beta cell mass in patients with diabetes. We report what we believe to be the first in vivo lineage tracing approach to determine the plasticity potential of pancreatic acinar cells. We developed an acinar cell-specific inducible Cre recombinase transgenic mouse, which, when mated with a reporter strain and pulsed with tamoxifen, resulted in permanent and specific labeling of acinar cells and their progeny. During various time periods of observation and using several models to provoke injury, we failed to observe any chase of the labeled cells into the endocrine compartment, indicating that acinar cells do not normally transdifferentiate into islet beta cells in vivo in adult mice. In contrast, we observed a substantial role for replication of preexisting acinar cells in the regeneration of new acinar cells after partial pancreatectomy. These results indicate that mature acinar cells harbor a facultative acinar but not endocrine progenitor capacity.

Two conserved domains in PCIF1 mediate interaction with pancreatic transcription factor PDX-1.

PCIF1 is a TRAF and POZ domain containing nuclear factor that interacts with and inhibits transactivation of pancreatic homeodomain transcription factor PDX-1. Here, we demonstrate interaction of endogenous PDX-1 and PCIF1 in MIN6 insulinoma cells. Within PCIF1, the TRAF and POZ domains are both required for physical and functional interaction with the C-terminus of PDX-1, whereas the C-terminal domain of PCIF1 directs its nuclear localization. A human PDX-1 mutation associated with diabetes, E224K, disrupts the ability of PCIF1 to inhibit PDX-1 transactivation, suggesting that the interaction between PDX-1 and PCIF1 is required for normal glucose homeostasis. Inhibition of transactivation occurs by a mechanism distinct from the classical role of POZ domains to recruit co-repressors and histone deacetylases. Understanding the functional roles of PCIF1 domains may have application to therapeutic beta-cell replacement strategies involving PDX-1 for the treatment of diabetes.

The thromboxane A2 receptor antagonist S18886 prevents enhanced atherogenesis caused by diabetes mellitus.

BACKGROUND: S18886 is an orally active thromboxane A2 (TXA2) receptor (TP) antagonist in clinical development for use in secondary prevention of thrombotic events in cardiovascular disease. We previously showed that S18886 inhibits atherosclerosis in apolipoprotein E-deficient (apoE(-/-)) mice by a mechanism independent of platelet-derived TXA2. Atherosclerosis is accelerated by diabetes and is associated with increased TXA(2) and other eicosanoids that stimulate TP. The purpose of this study was to determine whether S18886 lessens the enhanced atherogenesis in diabetic apoE(-/-) mice. METHODS AND RESULTS: Diabetes mellitus was induced in apoE(-/-) mice with streptozotocin and was treated or not with S18886 (5 mg.kg(-1).d(-1)). After 6 weeks, aortic lesion area was increased >4-fold by diabetes in apoE(-/-) mice, associated with similar increases in serum glucose and cholesterol. S18886 largely prevented the diabetes-related increase in lesion area without affecting the hyperglycemia or hypercholesterolemia. S18886 prevented deterioration of endothelial function and endothelial nitric oxide synthase expression, as well as increases in intimal markers of inflammation associated with diabetes. In human aortic endothelial cells in culture, S18886 also prevented the induction of vascular cell adhesion molecule-1 and prevented the decrease in endothelial nitric oxide synthase expression caused by high glucose. CONCLUSIONS: The TP antagonist inhibits inflammation and accelerated atherogenesis caused by diabetes, most likely by counteracting effects on endothelial function and adhesion molecule expression of eicosanoids stimulated by the diabetic milieu.