InR and Pi3K maintain intestinal homeostasis through STAT/EGFR and Notch signaling in enteroblasts.

To maintain the integrity of the adult gut, the proliferation and differentiation of stem cells must be strictly controlled. Several signaling pathways control the proliferation and differentiation of Drosophila intestinal epithelial cells. Although the modulatory effects of insulin pathway components on cell proliferation have been characterized, their specific role in which cell type and how these components interact with other regulatory signaling pathways remain largely unclear. In this study, we found that InR/Pi3K has major functions in enteroblasts (EBs) that were not previously described. The absence of InR/Pi3K in progenitors leads to a decrease in the number of EBs, while it has no significant effect on intestinal stem cells (ISCs). In addition, we found that InR/Pi3K regulates Notch activity in ISCs and EBs in an opposite way. This is also the reason for the decrease in EB. On the one hand, aberrantly low levels of Notch signaling in ISCs inhibit their proper differentiation into EBs; on the other hand, the higher Notch levels in EBs promote their excessive differentiation into enterocytes (ECs), leading to marked increases in abnormal ECs and decreased proliferation. Moreover, we found that Upd/JAK/STAT signaling acts as an effector or modifier of InR/Pi3K function in the midgut and cooperates with EGFR signaling to regulate cell proliferation. Altogether, our results demonstrate that InR and Pi3K are essential for coordinating stem cell differentiation and proliferation to maintain intestinal homeostasis.

A patient with multiple primary malignant neoplasms with high variant allele frequencies of RB1, TP53, and TERT.

Multiple primary malignant neoplasms are a rare disease with tumors of different histology or morphology arising in various sites. Next-generation sequencing is essential in the etiology, diagnosis, treatment, and surveillance of this disease. No eight primary malignant neoplasm cases with high variant allele frequencies of RB1, TP53, and TERT have been reported. Herein, we report a 65-year-old male who exhibited eight primary malignancies of the vocal cord, pharynx, kidney, mouth floor, esophagus, and urinary bladder with different pathological types. The first seven tumors were early-stage tumors; the last tumor, small cell carcinoma of urinary bladder, showed liver metastasis at diagnosis. Next-generation sequencing results revealed extremely high somatic variant allele frequencies of RB1 c.1472 T > C, TP53 c.576A > G, and TERT c.-58-u66C > T (95.5%, 95.1%, and 51.0%, respectively). No germline mutations were detected. These findings denoted a heavy tumor burden and poor prognosis. This is the first report of eight primary malignant neoplasm cases with high variant allele frequencies of RB1, TP53, and TERT.

The zinc finger protein CG12744 regulates intestinal stem cells in aged Drosophila through the EGFR and BMP pathways.

AIM: Aging is a process characterized by a time-dependent decline in the functionality of adult stem cells and is closely associated with age-related diseases. However, understanding how aging promotes disease and its underlying causes is critical for combating aging. MAIN METHODS: The offspring of UAS-Gal4 and CG12744RNAiDrosophila were cultured for 33 days to evaluate the role of CG12744 in the aging intestine. Immunofluorescence was performed to detect specific cell type markers for assessing proliferation and differentiation. qRT-PCR was used to observe the changes in signaling regulating intestinal homeostasis in the aging intestine after CG12744 knockdown. 16S rRNA-seq analysis was also conducted to elucidate the role of gut microbes in CG12744-mediated intestinal dysfunction. KEY FINDINGS: The mRNA levels of CG12744 were significantly increased in the aged midguts. Knockdown of CG12744 in progenitor cells further exacerbates the age-related intestinal hyperplasia and dysfunction. In particular, upon depletion of CG12744 in progenitors, enteroblasts (EBs) exhibited an increased propensity to differentiate along the enteroendocrine cell (EE) lineage. In contrast, the overexpression of CG12744 in progenitor cells restrained age-related gut hyperplasia in Drosophila. Moreover, CG12744 prevented age-related intestinal stem cell (ISC) overproliferation and differentiation by modulating the EGFR, JNK, and BMP pathways. In addition, the inhibition of CG12744 resulted in a significant increase in the gut microbial composition in aging flies. SIGNIFICANCE: This study established a role for the CG12744 in regulating the proliferation and differentiation of adult stem cells, thereby identifying a potential therapeutic target for diseases caused by age-related dysfunction stem cell dysfunction.

USP25 regulates KEAP1-NRF2 anti-oxidation axis and its inactivation protects acetaminophen-induced liver injury in male mice.

Nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor responsible for mounting an anti-oxidation gene expression program to counter oxidative stress. Under unstressed conditions, Kelch-like ECH-associated protein 1 (KEAP1), an adaptor protein for CUL3 E3 ubiquitin ligase, mediates NRF2 ubiquitination and degradation. We show here that the deubiquitinase USP25 directly binds to KEAP1 and prevents KEAP1's own ubiquitination and degradation. In the absence of Usp25 or if the DUB is inhibited, KEAP1 is downregulated and NRF2 is stabilized, allowing the cells to respond to oxidative stress more readily. In acetaminophen (APAP) overdose-induced oxidative liver damage in male mice, the inactivation of Usp25, either genetically or pharmacologically, greatly attenuates liver injury and reduces the mortality rates resulted from lethal doses of APAP.

N6-methyladenosine Modification of Noncoding RNAs: Mechanisms and Clinical Applications in Cancer.

N6-methyladenosine (m6A) modification remains the most pivotal epigenetic modification on RNA. As we know, m6A not only affects physiological processes but is also involved in carcinoma. Noncoding RNAs play an indispensable role in the occurrence and development of carcinoma. However, a large amount of research is focused on mRNA currently. Insufficient research has been done on the relationship between noncoding RNA (ncRNA) methylation and cancer. Therefore, this review aims to introduce the theoretical knowledge of m6A modification in noncoding RNA, discuss its function in tumorigenesis and progression, and ultimately summarize its potential clinical applications.

Advances in the application of Let-7 microRNAs in the diagnosis, treatment and prognosis of leukemia.

The lethal-7 (Let-7) family of microRNAs (miRNAs) controls the process of development and differentiation, but is also related to the occurrence of tumors and a poor prognosis of patients with tumors. Thus, a more comprehensive exploration of its functions will provide further insights into these processes, and may promote the diagnosis and treatment of tumors. Leukemia is a type of progressive malignant disease, and its pathogenesis involves a variety of epigenetic factors. Amongst the several related epigenetic factors, the Let-7 miRNAs are an important family of molecules that play a crucial role in maintaining a variety of critical biological processes, including development, differentiation and proliferation. In the present study, the role of Let-7 as a tumor suppressor gene and oncogene is reviewed, and the complex regulatory functions of several Let-7 family members in different subtypes of leukemia are described. The current body of knowledge thus far indicates that Let-7 is not only a potential diagnostic and prognostic marker of leukemia, but also a potential therapeutic target for the treatment of affected patients, with particular potential when targeted by adjuvant treatments alongside traditional treatment to improve their survival rate.

The deubiquitinase USP28 stabilizes the expression of RecQ family helicases and maintains the viability of triple negative breast cancer cells.

Triple-negative breast cancer (TNBC) lacks significant expression of the estrogen receptor, the progesterone receptor, and of human epidermal growth factor receptor. It is the most aggressive and malignant of all breast cancers, and for which, there are currently no effective targeted therapies. We have shown previously that the RecQ helicase family member RECQL5 is essential for the proliferation and survival of TNBC cells; however, the mechanism of its involvement in cell viability has not been shown. Here, we report that the expression of RecQ family helicases, including RECQL5, is regulated by the deubiquitinase USP28. We found using genetic depletion or a small molecule inhibitor that like RECQL5, USP28 is also essential for TNBC cells to proliferate in vitro and in vivo. Compromising the function of USP28 by shRNA knockdown or the inhibitor caused TNBC cells to arrest in S/G2 phases, concurrent with DNA-damage checkpoint activation. We further showed that the small molecule inhibitor of USP28 displayed anti-tumor activity against xenografts derived from TNBC cells. Our results suggest that USP28 could be a potential therapeutic target for triple negative breast cancer.

Anchor maintains gut homeostasis by restricting the JNK and Notch pathways in Drosophila.

The adult Drosophila intestinal epithelium must be tightly regulated to maintain regeneration and homeostasis. The dysregulation of the regenerative capacity is frequently associated with intestinal diseases such as inflammation and tumorigenesis. Here, we showed that the G protein-coupled receptor Anchor maintains Drosophila adult midgut homeostasis by restricting Jun-N-terminal kinase (JNK) and Notch pathway activity. anchor inactivation resulted in aberrant JNK pathway activation, which led to excessive enteroblast (EB) production and premature enterocyte (EC) differentiation. In addition, increased Notch levels promoted premature EC differentiation following the loss of anchor. This defect induced by the loss of anchor ultimately caused sensitivity to stress or environmental challenge in adult flies. Taken together, our results demonstrate that the activity of anchor is essential to coordinate stem cell differentiation and proliferation to maintain intestinal homeostasis.

Control measures to prevent Coronavirus disease 2019 pandemic in endoscopy centers: Multi-center study.

AIMS: To investigate control measures for COVID-19 pandemic in GIE centers in China. METHODS: This is a retrospective multi-center research, including seven centers. Data collection was from 1 February to 31 March 2020 and the same period in 2019. RESULTS: There were a total of 28 COVID-19 definite cases in these hospitals. Six out of seven GIE centers were arranged to shut down on 1 February, with a mean number of shutdown days of 23.6 ± 5.3. The actual workloads were only 10.3%-62.9% compared to those last year. All centers had a preoperative COVID-19 screening process. Epidemiological questionnaire, temperature taking and QR-code of journey were conducted. Chest CT scan was conducted during the shutdown period and continued in five centers after return to work. Antibody and nucleic acid test were applied in one to three centers. All endoscopists had advanced PPE. Five centers used surgical mask and the rest used N95 mask. Six centers used goggles or face shield. Five centers selected isolation gowns and the rest selected protective suits. The change frequency of these PPE was 4 h. Sterilizing measures were improved in six centers. Five centers utilized ultraviolet and six centers strengthened natural ventilation. Four and six centers used peracetic acid during the period of shutdown and return to work, alone or matched with OPA or acidified water. CONCLUSIONS: Many effective control measures were conducted in GIE centers during the outbreak, including patients' volume limitation, preoperative COVID-19 screening, advanced PPE and disinfection methods.

Caveolin1 protects against diet induced hepatic lipid accumulation in mice.

BACKGROUND AND AIM: Caveolin1 (CAV1) is involved in lipid homeostasis and endocytosis, but little is known about the significance of CAV1 in the pathogenesis and development of nonalcoholic fatty liver disease (NAFLD). This study aimed to determine the role of CAV1 in NAFLD. METHODS: Expression of CAV1 in the in vitro and in vivo models of NAFLD was analyzed. The effects of CAV1 knockdown or overexpression on free fatty acid (FFA)-induced lipid accumulation in L02 cells and AML12 cells were determined. CAV1 knockout (CAV1-KO) mice and their wild-type (WT) littermates were subjected to a high fat diet (HFD) for 4 weeks, and the functional consequences of losing the CAV1 gene and its subsequent molecular mechanisms were also examined. RESULTS: Noticeably, CAV1 expression was markedly reduced in NAFLD. CAV1 knockdown led to the aggravation of steatosis that was induced by FFA in both L02 cells and AML12 cells, while CAV1 overexpression markedly attenuated lipid accumulation in the cells. Consistent with CAV1 repression in the livers of HFD-induced mice, the CAV1-KO mice exhibited more severe hepatic steatosis upon HFD intake. In addition, increased cholesterol levels and elevated transaminases were detected in the plasma of CAV1-KO mice. The protein expression of SREBP1, a key gene involved in lipogenesis, was augmented following CAV1 suppression in FFA-treated hepatocytes and in the livers of HFD-fed CAV1-KO mice. CONCLUSIONS: CAV1 serves as an important protective factor in the development of NAFLD by modulating lipid metabolism gene expression.

Efficient gene editing in adult mouse livers via adenoviral delivery of CRISPR/Cas9.

We developed an adenovirus-based CRISPR/Cas9 system for gene editing in vivo. In the liver, we demonstrated that the system could reach the level of tissue-specific gene knockout, resulting in phenotypic changes. Given the wide spectrum of cell types susceptible to adenoviral infection, and the fact that adenoviral genome rarely integrates into its host cell genome, we believe the adenovirus-based CRISPR/Cas9 system will find applications in a variety of experimental settings.

Lipotoxic effect of p21 on free fatty acid-induced steatosis in L02 cells.

Nonalcoholic fatty liver disease (NAFLD) is increasingly regarded as a hepatic manifestation of metabolic syndrome. Though with high prevalence, the mechanism is poorly understood. This study aimed to investigate the effects of p21 on free fatty acid (FFA)-induced steatosis in L02 cells. We therefore analyzed the L02 cells with MG132 and siRNA treatment for different expression of p21 related to lipid accumulation and lipotoxicity. Cellular total lipid was stained by Oil Red O, while triglyceride content, cytotoxicity assays, lipid peroxidation markers and anti-oxidation levels were measured by enzymatic kits. Treatment with 1 mM FFA for 48 hr induced magnificent intracellular lipid accumulation and increased oxidative stress in p21 overload L02 cells compared to that in p21 knockdown L02 cells. By increasing oxidative stress and peroxidation, p21 accelerates FFA-induced lipotoxic effect in L02 cells and might provide information about potentially new targets for drug development and treatments of NAFLD.

Massilia lurida sp. nov., isolated from soil.

A bacterial isolate, designated strain D5(T), was isolated from a soil sample collected from the Inner Mongolia Autonomous Region, China, and subjected to a taxonomic investigation using a polyphasic approach. Strain D5(T) was aerobic, Gram-stain-negative, rod-shaped and motile. Strain D5(T) fell within the evolutionary radius of the genus Massilia in the phylogenetic tree based on 16S rRNA gene sequences and was most closely related to Massilia plicata 76(T) with 97.3% 16S rRNA gene sequence similarity. The predominant quinone of strain D5(T) was Q-8. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The major fatty acids were summed feature 3 (comprising C16:1ω7c and/or iso-C15:0 2-OH) and C16:0. These chemotaxonomic data supported the affiliation of strain D5(T) to the genus Massilia. The genomic DNA G+C content was 65.9 mol%. Mean DNA-DNA relatedness values between strain D5(T) and the phylogenetically most closely related species of the genus Massilia, Massilia plicata KCTC 12344(T) and Massilia dura KCTC 12342(T), were 26 and 21%, respectively. Strain D5(T) could be differentiated from recognized species of the genus Massilia by several phenotypic characteristics. It is clear from the data presented that strain D5(T) represents a novel species of the genus Massilia, for which the name Massilia lurida sp. nov. is proposed. The type strain is D5(T) (=CGMCC 1.10822(T)=KCTC 23880(T)).

Enhanced phenol bioavailability by means of photocatalysis.

Phenol was investigated for the ability of TiO2 photocatalysis to increase its bioavailability as an electron donor for denitrification. The rate of nitrate removal by denitrification was increased by up to 2.6-fold by exposing phenol to photocatalysis for 30 min, although the rate decreased with increasing photocatalysis. The increased denitrification rate appeared to be associated with the photocatalytic production of carboxylic acids, but the slow down correlated to the production of catechol and hydroquinone.

[Clinicopathologic analysis of nodal marginal zone B cell lymphoma].

OBJECTIVE: To investigate the clinicopathologic features of primary nodal marginal zone B-cell lymphoma (NMZL). METHODS: Hematoxylin-Eosin staining and immunohistochemistry were used to evaluate the histological and immunophenotypic characteristics of lymph node (LN) tissue in 22 NMZL cases. Additionally, interphase fluorescence in-situ hybridization (FISH) was carried out to detect the presence of t(11;18) (q21;q21)/API2-MALT1 and/or t(14;18)(q32;q21)/IGH-MALT1 in 9 cases. RESULTS: The median age of the 22 patients was 62 (16 - 77) ys. The male-to-female ratio was 1.2:1. All patients exhibited asymptomatic lymphadenopathy with the cervical region as the most often site to be involved (n = 11), followed by axillary (n = 9), inguinal (n = 7), submandibular (n = 6), mediastinal (n = 4), supraclavicular (n = 2) and retroperitoneal lymph nodes (n = 1). The Ann Arbor stages were I/II in 13 (59%) cases and III/IV in 9 (41%). Immunohistochemical study showed a consistently strong expression of CD20 and an absence in the expression of CD3ε, CD10, CD21, CD23, CyclinD1 and BCL6 by the tumor cells in all the cases. Frequency of expression of CD5 and BCL2 were 39% (7/18) and 30% (3/14) respectively. Among the 9 cases performed with FISH, 2 cases harbored t(14;18)and another 1 case positive for t(11;18) and t(14;18). Complete follow-up data were available for 13 cases. The follow-up time was 6 to 44 months. 3 of them died. 3-year cumulative survival rate was 67%. CONCLUSIONS: NMZL patients are often elderly, which mainly present with multiple lymphadenopathy, rare involvement of extranodal organ and early stage. The diagnosis must be based on a combination of clinicopathologic features, especially those patients detected t(11;18) and/or t(14;18).

Brevundimonas viscosa sp. nov., isolated from saline soil.

A Gram-negative, rod-shaped bacterial strain, designated F3(T), was isolated from a saline soil sample in China and studied by using a polyphasic taxonomic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain F3(T) was affiliated with the genus Brevundimonas, with Brevundimonas kwangchunensis KSL-102(T) (98.4 % similarity) and Brevundimonas alba DSM 4736(T) (98.2 %) as its closest relatives. Strain F3(T) contained ubiquinone-10 (Q-10) as the predominant ubiquinone and C(18 : 1)ω7c, C(17 : 1)ω8c and C(16 : 0) as the major fatty acids. The DNA G+C content of strain F3(T) was 66.7 mol%. Levels of DNA-DNA relatedness between strain F3(T) and the type strains of closely related Brevundimonas species were below 22 %. On the basis of phenotypic characteristics and genotypic distinctiveness, strain F3(T) should be classified as representing a novel species of the genus Brevundimonas, for which the name Brevundimonas viscosa sp. nov. is proposed. The type strain is F3(T) ( = CGMCC 1.10683(T) = JCM 17426(T)).