Integrating spin-dependent emission and dielectric switching in FeII catenated metal-organic frameworks

Mechanically interlocked molecules (MIMs) including famous catenanes show switchable physical properties and attract continuous research interest due to their potential application in molecular devices. The advantages of using spin crossover (SCO) materials here are enormous, allowing for control through diverse stimuli and highly specific functions, and enabling the transfer of the internal dynamics of MIMs from solution to solid state, leading to macroscopic applications. Herein, we report the efficient self-assembly of catenated metal-organic frameworks (termed catena-MOFs) induced by stacking interactions, through the combination of rationally selected flexible and conjugated naphthalene diimide-based bis-pyridyl ligand (BPND), [MI(CN)2]- (M = Ag or Au) and Fe2+ in a one-step strategy. The obtained bimetallic Hofmann-type SCO-MOFs [FeII(BPND){Ag(CN)2}2]·3CHCl3 (1Ag) and [FeII(BPND{Au(CN)2}2]·2CHCl3·2H2O (1Au) possess a unique three-dimensional (3D) catena-MOF constructed from the polycatenation of two-dimensional (2D) layers with hxl topology. Both complexes undergo thermal- and light-induced SCO. Significantly, abnormal increases in the maximum emission intensity and dielectric constant can be detected simultaneously with the switching of spin states. This research opens up SCO-actuated bistable MIMs that afford dual functionality of coupled fluorescence emission and dielectricity.

Urothelium-Specific Expression of Mutationally Activated Pik3ca Initiates Early Lesions of Noninvasive Bladder Cancer

Although approximately 70% of bladder cancers are noninvasive and have high recurrence rates, early-stage disease is understudied. The lack of models to validate the contribution of molecular drivers of bladder tumorigenesis is a significant issue. Although mutations in PIK3CA are frequent in human bladder cancer, an in vivo model for understanding their contribution to bladder tumorigenesis is unavailable. Therefore, a Upk2-Cre/Pik3caH1047R mouse model expressing one or two R26-Pik3caH1047R alleles in a urothelium-specific manner was generated. Pik3caH1047R functionality was confirmed by quantifying Akt phosphorylation, and mice were characterized by assessing urothelial thickness, nuclear atypia, and expression of luminal and basal markers at 6 and 12 months of age. While at 6 months, Pik3caH1047R mice developed increased urothelial thickness and nuclear atypia, progressive disease was not observed at 12 months. Immunohistochemistry showed urothelium maintained luminal differentiation characterized by high forkhead box A1 (Foxa1) and peroxisome proliferator-activated receptor γ expression. Surprisingly, Pik3caH1047R mice subjected to low-dose carcinogen exposure [N-butyl-N-(4-hydroxybutyl)nitrosamine] exhibited no significant differences after exposure relative to mice without exposure. Furthermore, single-sample gene set enrichment analysis of invasive human tumors showed those with mutant PIK3CA did not exhibit significantly increased phosphatidylinositol 3-kinase/AKT pathway activity compared with wild-type PIK3CA tumors. Overall, these data suggest that Pik3caH1047R can elicit early tumorigenic changes in the urothelium, but progression to invasion may require additional genetic alterations.

The Potent Anti-Tumor Effects of Rhodiola Drinking Are Associated with the Inhibition of the mTOR Pathway and Modification of Tumor Metabolism in the UPII-Mutant Ha-Ras Model

Background: SHR-5 has been used as an "adaptogen" for enhancing physical and mental performance and for fighting stress in the healthy population. The purpose of this study is to determine the chemopreventive efficacy of SHR-5 for superficial bladder cancer and to investigate the underlying mechanisms of action. Methods: UPII-mutant Ha-ras bladder-cancer-transgenic mice, that developed low-grade and noninvasive papillary transitional urothelial cell carcinoma, were fed with 1.25 and 6.25 mg/mL SHR-5 in drinking water for 6 months. The survival of the mice, obstructive uropathy, tumor burden and morphology, and proliferation were evaluated by pathological, molecular, metabolic, and statistical analyses. Results: Approximately 95% or more of the male UPII-mutant Ha-ras mice that drank SHR-5 daily survived over 6 months of age, while only 33.3% of those mice that drank normal water survived over 6 months of age (p < 0.0001); SHR-5 drinking exposure also reduced tumor-bearing bladder weight and urinary tract obstruction and inhibited mTOR signaling in neoplastic tissues. Global metabolic analysis revealed that SHR-5 resulted in increased phenolic metabolites and decreased CoA, a critical metabolic cofactor for lipid metabolism. Conclusions: Our findings highlight the potential of SHR-5 as an anti-aging agent for bladder cancer prevention through reshaping tumor metabolism via the inhibition of the mTOR signaling. Global metabolomics profiling provides a unique and efficient tool for studying the mechanisms of complex herb extracts' action.

Kawain Inhibits Urinary Bladder Carcinogenesis through Epigenetic Inhibition of LSD1 and Upregulation of H3K4 Methylation

Epidemiological evidence suggests that kava (Piper methysticum Forst) drinks may reduce the risk of cancer in South Pacific Island smokers. However, little is known about the anti-carcinogenic effects of kava on tobacco smoking-related bladder cancer and its underlying mechanisms. Here we show that dietary feeding of kawain (a major active component in kava root extracts) to mice either before or after hydroxy butyl(butyl) nitrosamine (OH-BBN) carcinogen exposure slows down urinary bladder carcinogenesis and prolongs the survival of the OH-BBN-exposed mice. OH-BBN-induced bladder tumors exhibit significantly increased expression of lysine-specific demethylase 1 (LSD1), accompanied by decreased levels of H3K4 mono-methylation compared to normal bladder epithelium, whereas dietary kawain reverses the effects of OH-BBN on H3K4 mono-methylation. Human bladder cancer tumor tissues at different pathological grades also show significantly increased expression of LSD1 and decreased levels of H3K4 mono-methylation compared to normal urothelium. In addition, kava root extracts and the kavalactones kawain and methysticin all increase the levels of H3K4 mono- and di-methylation, leading to inhibitory effects on cell migration. Taken together, our results suggest that modification of histone lysine methylation may represent a new approach to bladder cancer prevention and treatment and that kavalactones may be promising agents for bladder cancer interception in both current and former smokers.

Kavalactone Kawain Impedes Urothelial Tumorigenesis in UPII-Mutant Ha-Ras Mice via Inhibition of mTOR Signaling and Alteration of Cancer Metabolism

UPII-mutant Ha-ras transgenic mice develop urothelial hyperplasia and low-grade papillary carcinoma, which mimics human non-muscle invasive bladder cancer (NMIBC). We investigated the effects and mechanisms of kawain, a main kavalactone in the kava plant, on oncogenic Ha-ras-driven urothelial carcinoma in these mice. The mice were fed at six weeks of age with vehicle control or kawain (6 g/kg) formulated food for approximately five months. Seventy-eight percent of the mice or more fed with kawain food survived more than six months of age, whereas only 32% control food-fed male mice survived, (p = 0.0082). The mean wet bladder weights (a surrogate for tumor burden) of UPII-mutant Ha-ras transgenic mice with kawain diet was decreased by approximately 56% compared to those fed with the control diet (p = 0.035). The kawain diet also significantly reduced the occurrence of hydronephrosis and hematuria in UPII-mutant Ha-ras transgenic mice. Histological examination and immunohistochemistry analysis revealed that vehicle control-treated mice displayed more urothelial carcinoma and Ki67-positive cells in the bladder compared to kawain treated mice. Global metabolic profiling of bladder tumor samples from mice fed with kawain food showed significantly more enrichment of serotonin and less abundance of xylulose, prostaglandin A2, D2 and E2 compared to those from control diet-fed mice, suggesting decreased shunting of glucose to the pentose phosphate pathway (PPP) and reduced inflammation. In addition, kawain selectively inhibited the growth of human bladder cancer cell lines with a significant suppression of 4E-BP1 expression and rpS6 phosphorylation. These observations indicate a potential impact of kawain consumption on bladder cancer prevention by rewiring the metabolic programs of the tumor cells.

Structural or functional defects of PTEN in urothelial cells lacking P53 drive basal/squamous-subtype muscle-invasive bladder cancer

Muscle-invasive bladder cancer (MIBC) exhibits strong inter- and intra-tumor heterogeneity that affects biological behaviors, therapeutic responses, and prognoses. Mutations that activate RTK-RAS-PI3K and inactivate P19-P53-P21 coexist in 60-70% of MIBC. By time-controlled ablation of Tp53 and Pten, singly or combined, in adult mouse urothelium, we found that Tp53 loss alone produced no abnormality. While Pten loss elicited hyperplasia, it synergized with Tp53 loss to trigger 100% penetrant MIBC that exhibited basal/squamous features that resembled its human counterpart. Furthermore, PTEN was inactivated in human MIBC cell lines and specimens primarily by hyperphosphorylation of the C-terminus. Mutated or tailless PTEN incapable of C-terminal phosphorylation demonstrated increased inhibition of proliferation and invasion than full-length PTEN in cultured MIBC cells. In xenograft and transgenic mice, tailless PTEN, but not full-length PTEN, prevented further growth in established tumors. Collectively, deficiencies of both PTEN and P53 drive basal/squamous subtype MIBC. PTEN is inactivated by C-terminal hyperphosphorylation, and this modification may serve as a biomarker for subtyping MIBC and predicting tumor progression. Tailless PTEN is a potential molecular therapeutic for tumors, such as bladder cancer (BC), that can be readily accessed.

Assembly of a Heterotrimetallic Zn2Dy2Ir Pentanuclear Complex toward Multifunctional Molecular Materials

Rational selection of metal ions and organic ligands to synthesize metal-organic complexes (MOCs) is necessary for constructing multifunctional materials. Herein, we have obtained a novel heterotrimetallic Zn₂Dy₂Ir pentanuclear MOC by the assembly of Dy^III, luminescent Zn^II(valpn), and [Ir^III(H₂L)(ppy)₂]Cl metalloligands (Hppy = 2-phenylpyridine, H₂L = 2,2'-bipyridine-5,5'-di-p-benzoic acid). Single-crystal structural analysis shows that the central [Ir^III(L)(ppy)₂]^- bridges two ZnDy moieties using two carboxylates of L^2-. Measurements of organic light-emitting diodes (OLEDs) show that the maximum luminance is 284.2 cd/m² and the turn-on voltage is 6 V. Magnetic studies reveal that Zn₂Dy₂Ir is a field-induced single-molecule magnet (SMM) with an energy barrier of 19.1(2) K under a 2 kOe dc field. Zn₂Dy₂Ir shows luminescence sensing with a quenching efficiency of up to 99.0% for 2,4,6-trinitrophenol (TNP).

DNMT3A/miR-129-2-5p/Rac1 Is an Effector Pathway for SNHG1 to Drive Stem-Cell-like and Invasive Behaviors of Advanced Bladder Cancer Cells

The stem-cell-like behavior of cancer cells plays a central role in tumor heterogeneity and invasion and correlates closely with drug resistance and unfavorable clinical outcomes. However, the molecular underpinnings of cancer cell stemness remain incompletely defined. Here, we show that SNHG1, a long non-coding RNA that is over-expressed in ~95% of human muscle-invasive bladder cancers (MIBCs), induces stem-cell-like sphere formation and the invasion of cultured bladder cancer cells by upregulating Rho GTPase, Rac1. We further show that SNHG1 binds to DNA methylation transferase 3A protein (DNMT3A), and tethers DNMT3A to the promoter of miR-129-2, thus hyper-methylating and repressing miR-129-2-5p transcription. The reduced binding of miR-129-2 to the 3'-UTR of Rac1 mRNA leads to the stabilization of Rac1 mRNA and increased levels of Rac1 protein, which then stimulates MIBC cell sphere formation and invasion. Analysis of the Human Protein Atlas shows that a high expression of Rac1 is strongly associated with poor survival in patients with MIBC. Our data strongly suggest that the SNHG1/DNMT3A/miR-129-2-5p/Rac1 effector pathway drives stem-cell-like and invasive behaviors in MIBC, a deadly form of bladder cancer. Targeting this pathway, alone or in combination with platinum-based therapy, may reduce chemoresistance and improve longer-term outcomes in MIBC patients.

The kidney protects against sepsis by producing systemic uromodulin

Sepsis is a significant cause of mortality in hospitalized patients. Concomitant development of acute kidney injury (AKI) increases sepsis mortality through unclear mechanisms. Although electrolyte disturbances and toxic metabolite buildup during AKI could be important, it is possible that the kidney produces a protective molecule lost during sepsis with AKI. We have previously demonstrated that systemic Tamm-Horsfall protein (THP; uromodulin), a kidney-derived protein with immunomodulatory properties, falls in AKI. Using a mouse sepsis model without severe kidney injury, we showed that the kidney increases circulating THP by enhancing the basolateral release of THP from medullary thick ascending limb cells. In patients with sepsis, changes in circulating THP were positively associated with a critical illness. THP was also found de novo in injured lungs. Genetic ablation of THP in mice led to increased mortality and bacterial burden during sepsis. Consistent with the increased bacterial burden, the presence of THP in vitro and in vivo led macrophages and monocytes to upregulate a transcriptional program promoting cell migration, phagocytosis, and chemotaxis, and treatment of macrophages with purified THP increases phagocytosis. Rescue of septic THP-/- mice with exogenous systemic THP improved survival. Together, these findings suggest that through releasing THP, the kidney modulates the immune response in sepsis by enhancing mononuclear phagocyte function, and systemic THP has therapeutic potential in sepsis.NEW & NOTEWORTHY Specific therapies to improve outcomes in sepsis with kidney injury have been limited by an unclear understanding of how kidney injury increases sepsis mortality. Here, we identified Tamm-Horsfall protein, known to protect in ischemic acute kidney injury, as protective in preclinical sepsis models. Tamm-Horsfall protein also increased in clinical sepsis without severe kidney injury and concentrated in injured organs. Further study could lead to novel sepsis therapeutics.

PKM2 Is Essential for Bladder Cancer Growth and Maintenance

Pyruvate kinase M2 (PKM2) has been shown to promote tumorigenesis by facilitating the Warburg effect and enhancing the activities of oncoproteins. However, this paradigm has recently been challenged by studies in which the absence of PKM2 failed to inhibit and instead accelerated tumorigenesis in mouse models. These results seem inconsistent with the fact that most human tumors overexpress PKM2. To further elucidate the role of PKM2 in tumorigenesis, we investigated the effect of PKM2 knockout in oncogenic HRAS-driven urothelial carcinoma. While PKM2 ablation in mouse urothelial cells did not affect tumor initiation, it impaired the growth and maintenance of HRAS-driven tumors. Chemical inhibition of PKM2 recapitulated these effects. Both conditions substantially reduced complex formation of PKM2 with STAT3, their nuclear translocation, and HIF1α- and VEGF-related angiogenesis. The reduction in nuclear STAT3 in the absence of PKM2 also correlated with decreased autophagy and increased apoptosis. Time-controlled, inducible PKM2 overexpression in simple urothelial hyperplasia did not trigger tumorigenesis, while overexpression of PKM2, but not PKM1, in nodular urothelial hyperplasia with angiogenesis strongly accelerated tumorigenesis. Finally, in human patients, PKM2 was overexpressed in low-grade nonmuscle-invasive and high-grade muscle-invasive bladder cancer. Based on these data, PKM2 is not required for tumor initiation but is essential for tumor growth and maintenance by enhancing angiogenesis and metabolic addiction. The PKM2-STAT3-HIF1α/VEGF signaling axis may play a critical role in bladder cancer and may serve as an actionable therapeutic target.

SIGNIFICANCE

Genetic manipulation and pharmacologic inhibition of PKM2 in mouse urothelial lesions highlight its essential role in promoting angiogenesis and metabolic addiction, events indispensable for tumor growth and maintenance.

Magnetooptical Properties of Lanthanide(III) Metal-Organic Frameworks Based on an Iridium(III) Metalloligand

Integrating magnetic and optical properties into a metal-organic framework (MOF) remains a great challenge. Herein, we have reasonably constructed two 3D magnetooptical MOFs by incorporating a [Ir^III(ppy)₂(bpy)]⁺-based fluorescent metalloligand and magnetic Ln^III centers. The alternating arrangements of Δ- or Λ-[Ir^III(ppy)₂(bpy)]⁺ endow these MOFs with enhanced optical properties. Moreover, the use of Dy^III leads to field-induced slow magnetic relaxation. This work provides an effective strategy for the preparation of magnetooptical bifunctional MOFs.

DNA damage, DNA repair and carcinogenicity: Tobacco smoke versus electronic cigarette aerosol

The allure of tobacco smoking is linked to the instant gratification provided by inhaled nicotine. Unfortunately, tobacco curing and burning generates many mutagens including more than 70 carcinogens. There are two types of mutagens and carcinogens in tobacco smoke (TS): direct DNA damaging carcinogens and procarcinogens, which require metabolic activation to become DNA damaging. Recent studies provide three new insights on TS-induced DNA damage. First, two major types of TS DNA damage are induced by direct carcinogen aldehydes, cyclic-1,N2-hydroxy-deoxyguanosine (γ-OH-PdG) and α-methyl-1, N2-γ-OH-PdG, rather than by the procarcinogens, polycyclic aromatic hydrocarbons and aromatic amines. Second, TS reduces DNA repair proteins and activity levels. TS aldehydes also prevent procarcinogen activation. Based on these findings, we propose that aldehydes are major sources of TS induce DNA damage and a driving force for carcinogenesis. E-cigarettes (E-cigs) are designed to deliver nicotine in an aerosol state, without burning tobacco. E-cigarette aerosols (ECAs) contain nicotine, propylene glycol and vegetable glycerin. ECAs induce O6-methyl-deoxyguanosines (O6-medG) and cyclic γ-hydroxy-1,N2--propano-dG (γ-OH-PdG) in mouse lung, heart and bladder tissues and causes a reduction of DNA repair proteins and activity in lungs. Nicotine and nicotine-derived nitrosamine ketone (NNK) induce the same types of DNA adducts and cause DNA repair inhibition in human cells. After long-term exposure, ECAs induce lung adenocarcinoma and bladder urothelial hyperplasia in mice. We propose that E-cig nicotine can be nitrosated in mouse and human cells becoming nitrosamines, thereby causing two carcinogenic effects, induction of DNA damage and inhibition of DNA repair, and that ECA is carcinogenic in mice. Thus, this article reviews the newest literature on DNA adducts and DNA repair inhibition induced by nicotine and ECAs in mice and cultured human cells, and provides insights into ECA carcinogenicity in mice.

The role of TAp63γ and P53 point mutations in regulating DNA repair, mutational susceptibility and invasion of bladder cancer cells

It has long been recognized that non-muscle-invasive bladder cancer (NMIBC) has a low propensity (20%) of becoming muscle-invasive (MIBC), and that MIBC carry many more p53 point mutations (p53m) than NMIBC (50% vs 10%). MIBC also has a higher mutation burden than NMIBC. These results suggest that DNA repair capacities, mutational susceptibility and p53m are crucial for MIBC development. We found MIBC cells are hypermutable, deficient in DNA repair and have markedly downregulated DNA repair genes, XPC, hOGG1/2 and Ref1, and the tumor suppressor, TAp63γ. In contrast, NMIBC cells are hyperactive in DNA repair and exhibit upregulated DNA repair genes and TAp63γ. A parallel exists in human tumors, as MIBC tissues have markedly lower DNA repair activity, and lower expression of DNA repair genes and TAp63γ compared to NMIBC tissues. Forced TAp63γ expression in MIBC significantly mitigates DNA repair deficiencies and reduces mutational susceptibility. Knockdown of TAp63γ in NMIBC greatly reduces DNA repair capacity and enhances mutational susceptibility. Manipulated TAp63γ expression or knockdown of p53m reduce the invasion of MIBC by 40–60%. However, the combination of p53m knockdown with forced TAp63γ expression reduce the invasion ability to nil suggesting that p53m contributes to invasion phenotype independent from TAp63γ. These results indicate that in BC, TAp63γ regulates DNA repair capacities, mutational susceptibility and invasion, and that p53m contribute to the invasion phenotype. We conclude that concurrent TAp63γ suppression and acquisition of p53m are a major cause for MIBC development.

[Meta-analysis of the effects of statins on the risk of chronic liver disease and hepatocellular carcinoma]

Objective: To evaluate the relationship between the application of statins and the risk of hepatocellular carcinoma in patients with chronic liver disease. Methods: PubMed, the Cochrane Library, EMBASE, Web of science, WeiPu, Wanfang Med online, and China National Knowledge Infrastructure database were searched. The literatures about statins and the risk of hepatocellular carcinoma in patients with chronic liver disease were collected, with a search deadline of February 2020. Two researchers independently conducted literature screening, data extraction, quality evaluation and proofreading. RevMan5.3 software was used for data analysis. The I2 combined with χ (2) test was used to evaluate the heterogeneity. Funnel plots were used to evaluate the publication bias of the included literature. Results: A total of 12 articles were included. Statins application had significantly reduced the risk of hepatocellular carcinoma in patients with chronic liver disease (OR = 0.50, 95% CI: 0.43~0.58, P < 0.01). Subgroup analysis showed that statins had reduced the incidence rate of hepatocellular carcinoma in patients with chronic hepatitis B (OR = 0.56, 95% CI: 0.47~0.66, P < 0.01) and chronic hepatitis C (OR = 0.56, 95% CI: 0.45~0.71, P < 0.01). Lipophilic statins had significantly reduced the risk of chronic liver disease development to hepatocellular carcinoma (OR = 0.48, 95% CI: 0.39~0.59, P < 0.01), but hydrophilic statins did not reduce the incidence rate of chronic liver disease development to hepatocellular carcinoma, and the difference was not statistically significant (OR = 0.64, 95% CI: 0.36~1.14, P = 0.13). Conclusion: Statins can effectively reduce the risk of hepatocellular carcinoma development in patients with chronic liver disease, including chronic hepatitis B and C. Among them, the lipophilic statins have a significant preventive effect on the development of chronic liver disease to hepatocellular carcinoma, but hydrophilic statins have no obvious effect.

Episodic Aspiration with Oral Commensals Induces a MyD88-dependent, Pulmonary T-Helper Cell Type 17 Response that Mitigates Susceptibility to Streptococcus pneumoniae

Rationale: Cross-sectional human data suggest that enrichment of oral anaerobic bacteria in the lung is associated with an increased T-helper cell type 17 (Th17) inflammatory phenotype.Objectives: In this study, we evaluated the microbial and host immune-response dynamics after aspiration with oral commensals using a preclinical mouse model.Methods: Aspiration with a mixture of human oral commensals (MOC; Prevotella melaninogenica, Veillonella parvula, and Streptococcus mitis) was modeled in mice followed by variable time of killing. The genetic backgrounds of mice included wild-type, MyD88-knockout, and STAT3C backgrounds.Measurements and Main Results: 16S-rRNA gene sequencing characterized changes in microbiota. Flow cytometry, cytokine measurement via Luminex and RNA host-transcriptome sequencing was used to characterize the host immune phenotype. Although MOC aspiration correlated with lower-airway dysbiosis that resolved within 5 days, it induced an extended inflammatory response associated with IL-17-producing T cells lasting at least 14 days. MyD88 expression was required for the IL-17 response to MOC aspiration, but not for T-cell activation or IFN-γ expression. MOC aspiration before a respiratory challenge with S. pneumoniae led to a decrease in hosts' susceptibility to this pathogen.Conclusions: Thus, in otherwise healthy mice, a single aspiration event with oral commensals is rapidly cleared from the lower airways but induces a prolonged Th17 response that secondarily decreases susceptibility to S. pneumoniae. Translationally, these data implicate an immunoprotective role of episodic microaspiration of oral microbes in the regulation of the lung immune phenotype and mitigation of host susceptibility to infection with lower-airway pathogens.

Circulating uromodulin inhibits systemic oxidative stress by inactivating the TRPM2 channel

High serum concentrations of kidney-derived protein uromodulin [Tamm-Horsfall protein (THP)] have recently been shown to be independently associated with low mortality in both older adults and cardiac patients, but the underlying mechanism remains unclear. Here, we show that THP inhibits the generation of reactive oxygen species (ROS) both in the kidney and systemically. Consistent with this experimental data, the concentration of circulating THP in patients with surgery-induced acute kidney injury (AKI) correlated with systemic oxidative damage. THP in the serum dropped after AKI and was associated with an increase in systemic ROS. The increase in oxidant injury correlated with postsurgical mortality and need for dialysis. Mechanistically, THP inhibited the activation of the transient receptor potential cation channel, subfamily M, member 2 (TRPM2) channel. Furthermore, inhibition of TRPM2 in vivo in a mouse model mitigated the systemic increase in ROS during AKI and THP deficiency. Our results suggest that THP is a key regulator of systemic oxidative stress by suppressing TRPM2 activity, and our findings might help explain how circulating THP deficiency is linked with poor outcomes and increased mortality.

[Effects of ilioinguinal composite tissue flaps in repairing skin and soft tissue defects on hand or foot]

Objective: To explore the effects of ilioinguinal composite tissue flaps in repairing skin and soft tissue defects on hand or foot and reconstructing the flexion and extension functions of wrist, finger, ankle, and toe. Methods: From February 2012 to March 2018, 4, 5, and 3 patients (11 males and 1 female, 23-62 years old) with skin and soft tissue defects on hand or foot were admitted to Traditional Chinese Medicine Hospital of Zhongmu County of Henan Province, Henan Armed Police Corps Hospital, and the Affiliated Jiangyin Hospital of Medical College of Southeast University, respectively. Five patients had hand defects, and 7 patients had foot defects. The areas of skin and soft tissue defects after debridement were 10 cm×8 cm-15 cm×10 cm. The ilioinguinal composite tissue flaps were designed and resected according to the wound area and the length of tendon defects, and the areas of flaps were 10 cm×8 cm-15 cm×12 cm. According to the specific condition of the recipient area, the superficial iliac circumflex artery in the tissue flap was reconstructed by end-to-side anastomosis in 2 patients and end-to-end anastomosis in 1 patient with ulnar artery, end-to-side anastomosis in 4 patients with the dorsal foot artery, end-to-side anastomosis in 2 patients with the posterior tibial artery, and end-to-end anastomosis in 1 patient with the external tarsal foot artery in the recipient area, and the superficial epigastric artery in the tissue flap was reconstructed by end-to-side anastomosis in 1 patient with the radial artery and end-to-end anastomosis in 1 patient with the ulnar artery in the recipient area. The donor sites were sutured directly or repaired with medium split-thickness skin grafts. The survival of tissue flap after the operation and the appearance, texture, and the two-point discrimination distance of the tissue flaps during follow-up were observed. The hand function and foot function were evaluated by the total active movement standard of hand and the Maryland foot score standard, respectively. Results: All the tissue flaps in 12 patients survived. During follow-up of 6-36 months after operation, the tissue flaps were slightly bloated, with linear scars at the junction site in the recipient area, and the two-point discrimination distances of the tissue flaps were 15-22 mm. The hand function was excellent in 3 cases, good in 1 case, and fair in 1 case, and the foot function was excellent in 4 cases, good in 2 cases, and fair in 1 case, and all the patients were satisfied with the function and appearance of hand or foot. Conclusions: The ilioinguinal composite tissue flaps can repair the hand and foot wounds and reconstruct the flexion and extension functions of wrist, finger, ankle, and toe at the same time, which is an effective method to repair this kind of defects.

Uromodulin (Tamm-Horsfall protein): guardian of urinary and systemic homeostasis

Biology has taught us that a protein as abundantly made and conserved among species as Tamm-Horsfall protein (THP or uromodulin) cannot just be a waste product serving no particular purpose. However, for many researchers, THP is merely a nuisance during urine proteome profiling or exosome purification and for clinicians an enigmatic entity without clear disease implications. Thanks to recent human genetic and correlative studies and animal modeling, we now have a renewed appreciation of this highly prevalent protein in not only guarding urinary homeostasis, but also serving as a critical mediator in systemic inter-organ signaling. Beyond a mere barrier that lines the tubules, or a surrogate for nephron mass, mounting evidence suggests that THP is a multifunctional protein critical for modulating renal ion channel activity, salt/water balance, renal and systemic inflammatory response, intertubular communication, mineral crystallization and bacterial adhesion. Indeed, mutations in THP cause a group of inherited kidney diseases, and altered THP expression is associated with increased risks of urinary tract infection, kidney stone, hypertension, hyperuricemia and acute and chronic kidney diseases. Despite the recent surge of information surrounding THP's physiological functions and disease involvement, our knowledge remains incomplete regarding how THP is normally regulated by external and intrinsic factors, how precisely THP deficiency leads to urinary and systemic pathophysiology and in what clinical settings THP can be used as a theranostic biomarker and a target for modulation to improve patient outcomes.

Abstract IA18: Genetic modeling of bladder cancer in the post-genome era

The ability to profile the genome and transcriptome of bladder cancer on a global scale has fundamentally changed the way bladder cancer is diagnosed, treated, and prognosticated. As large amounts of information continue to accrue from the whole-genome/exome/transcriptome analyses of human materials, is genetic modeling of bladder cancer still necessary and useful? The answer is clearly an affirmative one based on the following reasons. First and foremost, we continue to need genetically tractable experimental systems to validate the biologic potential of putative tumor drivers, distinguish them from the passenger abnormalities, and ascertain whether they are initiators of tumor formation or promoters of tumor progression. There are ample examples where recurrent mutations identified in humans by themselves completely lack tumorigenicity and instead require specific collaborative events to initiate tumors. Perhaps the best example relates to the mutations that activate the receptor tyrosine kinase (RTK)-RAS-PI3K signaling pathway. Despite the fact that most if not all non-muscle invasive bladder cancer (NMIBC) harbors at least one mutation in this pathway, none of the mutations affecting different genes (e.g., FGFR3, RAS, PIK3CA, or PTEN deletion) is overtly tumorigenic in mouse models. By systematically dissecting the biologic effects of the loss of several individual genes residing on 9p21, my laboratory has obtained new data (which I will discuss), implicating the specific cooperative events that are both necessary and sufficient to initiate NMIBC during the activation of RTK-RAS-PI3K pathway. The lack of tumorigenicity of p53 mutation/deletion, alone or in combination with RB1 loss, in the genesis of MIBC is another notable example. For these reasons, additional studies are therefore required to pin down the driver events underlying NMIBC versus MIBC. Second, because bladder cancer is primarily a carcinogen-induced cancer, we continue to need model systems to investigate how lifestyle-associated carcinogens, such as tobacco smoke and e-cigarette smoke, and environment-associated carcinogens, such as aromatic amines, acrolein, and arsenic, inflict damages on our genome and epigenome. Bladder cancer is likely a result of long-term exposure to an assortment of carcinogens, but our understanding about the changes at the carcinogen-genome interface remains extremely scarce. The model systems should be highly instrumental in allowing us to better assess risks in carcinogen exposure and informing us about effective prevention strategies. Third, some of unresolved issues regarding the cell(s) of origin of bladder cancer variants and subtypes and the bases underlying the inter- and intratumor heterogeneity can be greatly facilitated by lineage-specific targeting and tracing in mouse models. Fourth, we continue to need a toolbox with which to critically evaluate new concepts and strategies in diagnosis and treatment. In the post-genome era, the demand for human-relevant model systems in this area will be considerably more, not less, than before. Models worthy of particular attention include those that can be used to test chemosensitivity, immunotherapeutics, and combination-therapy modalities. Finally, the continued need for genetic model systems will be shaped by more sophisticated modeling strategies and methods. For instance, the modelers will likely prioritize genetic and epigenetic alterations that are highly prevalent in human specimens over less prevalent ones, conditional systems over constitutive ones, and lineage-specific targeting over whole-urothelial targeting. There will also likely be an increased use of genome editing techniques, such as CRISPR/Cas9, in creating somatic models of bladder cancer, instead of just germline mutations.

Citation Format: Xue-Ru Wu. Genetic modeling of bladder cancer in the post-genome era [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2019 May 18-21; Denver, CO. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(15_Suppl):Abstract nr IA18.

[Differences in the bone marrow histopathology between pediatric acquired aplastic anemia and refractory cytopenia of childhood]

Objective: To study the differences in the bone marrow histopathology between acquired aplastic anemia (AAA) in children and refractory cytopenia of childhood (RCC) to facilitate their diagnoses and differential diagnosis. Methods: The clinical data and bone marrow biopsies of the RCC and AAA cases diagnosed from January 2008 to December 2018 in Xinhua Hospital, Shanghai Jiaotong University School of Medicine and Shanghai Children's Medical Center affiliated to Shanghai Jiaotong University School of Medicine were analyzed. Results: A total of 71 AAA and 79 RCC cases were analyzed. There were 52 males and 19 females, age ranged 1.0-15.0 years (median, 8.9 years) in the AAA group, and 53 males and 26 females, age ranged 0.5-16.0 years (median, 5.0 years) in the RCC group. All the biopsy specimens of AAA patients had severe hypocellularity; the cellularity of 88.7% (63/71) specimens was under 5.0%, and 11.3%(8/71) was 5%-24%. None of the AAA specimens showed any dysplastic change. All the biopsy specimens of RCC patients had hypocellularity, including 94.9%(75/79) of the specimens with a cellularity of 5%-50%. All of the RCC specimens showed a patchy distribution of hematopoiesis. A dysplastic change of erythroid cells and micromegakaryocytes was found in 40.5% (32/79) and in 60.8% (48/79) of the RCC cases, respectively. Conclusions: The degree of hypocellularity, the distribution pattern of hematopoiesis, the cell composition and localization of erythroid cell clusters and the appearance of micromegaryocytes could help the diagnosis and differential diagnosis of AAA and RCC.

Downregulation of miR-200c stabilizes XIAP mRNA and contributes to invasion and lung metastasis of bladder cancer

Our previous studies have demonstrated that XIAP promotes bladder cancer metastasis through upregulating RhoGDIβ/MMP-2 pathway. However, the molecular mechanisms leading to the XIAP upregulation was unclear. In current studies, we found that XIAP was overexpressed in human high grade BCs, high metastatic human BCs, and in mouse invasive BCs. Mechanistic studies indicated that XIAP overexpression in the highly metastatic T24T cells was due to increased mRNA stability of XIAP that was mediated by downregulated miR-200c. Moreover, the downregulated miR-200c was due to CREB inactivation, while miR-200c downregulation reduced its binding to the 3’-UTR region of XIAP mRNA. Collectively, our results demonstrate the molecular basis leading to XIAP overexpression and its crucial role in BC invasion.

[Clinical phenotypes of epilepsy associated with GABRA1 gene variants]

Objective: To summarize the clinical phenotypes of epilepsy in patients with GABRA1 gene variants. Methods: A total of 11 epileptic patients (4 boys and 7 girls) who were treated in the Department of Pediatrics, Peking University First Hospital from March 2016 to July 2019 and detected with GABRA1 gene heterozygous pathogenic variants by targeted next-generation sequencing were enrolled. The features of clinical manifestations, electroencephalogram (EEG), and neuroimaging were analyzed retrospectively. Results: A total of 11 epileptic patients carried GABRA1 gene pathogenic variants, of whom 10 were de novo variants and the other one was inherited from the patient's mother. Two patients had the same variants. Six variants were novel. Ages at seizure onset ranged from 3 to 14 months, and the median age was 8 months. The seizure was first observed within 1 year in 10 patients and beyond 1 year of age in 1 patient. Multiple seizure types were observed, including focal seizures in 10 patients, generalized tonic clonic seizures (GTCS) in 3 patients, myoclonic seizures in 3 patients, and epileptic spasm in 2 patients. There were 5 patients with multiple seizure types. Sensitivity to fever was observed in 9 patients, among whom 6 patients had a history of status epilepticus. Two patients had photoparoxysmal response. Five patients had abnormal EEG background, and 6 patients had abnormal discharges in EEG during interictal phase. Brain magnetic resonance imaging (MRI) was normal in all patients. Developmental delay in various degrees was present in 9 patients. Among the 11 patients, Dravet syndrome was diagnosed in 5 patients, West syndrome in 2 patients, undiagnosed early-onset epileptic encephalopathy in 1 patient, and focal epilepsy in the other 3 patients. The ages at the last follow-up ranged from 8 months to 12 years. During follow-up, 8 patients were seizure-free for 6 months to 8 years, and 1 patient had discontinuation of medication. Conclusions: In epilepsy associated with GABRA1 gene variants, de novo pathogenic variants are more common than inherited. Most epilepsy caused by GABRA1 gene variants occurs in infancy. Most patients have multiple seizures and focal seizures are common. Most patients have a comparatively favorable prognosis, but they may still have varied degrees of developmental delay.

Electronic-cigarette smoke induces lung adenocarcinoma and bladder urothelial hyperplasia in mice

Electronic-cigarettes (E-cigs) are marketed as a safe alternative to tobacco to deliver the stimulant nicotine, and their use is gaining in popularity, particularly among the younger population. We recently showed that mice exposed to short-term (12 wk) E-cig smoke (ECS) sustained extensive DNA damage in lungs, heart, and bladder mucosa and diminished DNA repair in lungs. Nicotine and its nitrosation product, nicotine-derived nitrosamine ketone, cause the same deleterious effects in human lung epithelial and bladder urothelial cells. These findings raise the possibility that ECS is a lung and bladder carcinogen in addition to nicotine. Given the fact that E-cig use has become popular in the past decade, epidemiological data on the relationship between ECS and human cancer may not be known for a decade to come. In this study, the carcinogenicity of ECS was tested in mice. We found that mice exposed to ECS for 54 wk developed lung adenocarcinomas (9 of 40 mice, 22.5%) and bladder urothelial hyperplasia (23 of 40 mice, 57.5%). These lesions were extremely rare in mice exposed to vehicle control or filtered air. Current observations that ECS induces lung adenocarcinomas and bladder urothelial hyperplasia, combined with our previous findings that ECS induces DNA damage in the lungs and bladder and inhibits DNA repair in lung tissues, implicate ECS as a lung and potential bladder carcinogen in mice. While it is well established that tobacco smoke poses a huge threat to human health, whether ECS poses any threat to humans is not yet known and warrants careful investigation.