The role of tRF-Val-CAC-010 in lung adenocarcinoma: implications for tumorigenesis and metastasis.

OBJECTIVE: Transfer RNA-derived fragments (tRFs) are short non-coding RNA (ncRNA) sequences, ranging from 14 to 30 nucleotides, produced through the precise cleavage of precursor and mature tRNAs. While tRFs have been implicated in various diseases, including cancer, their role in lung adenocarcinoma (LUAD) remains underexplored. This study aims to investigate the impact of tRF-Val-CAC-010, a specific tRF molecule, on the phenotype of LUAD cells and its role in tumorigenesis and progression in vivo. METHODS: The expression level of tRF-Val-CAC-010 was quantified using quantitative real-time polymerase chain reaction (qRT-PCR). Specific inhibitors and mimics of tRF-Val-CAC-010 were synthesized for transient transfection. Cell proliferation was assessed using the Cell Counting Kit-8 (CCK-8), while cell invasion and migration were evaluated through Transwell invasion and scratch assays. Flow cytometry was utilized to analyze cell cycle and apoptosis. The in vivo effects of tRF-Val-CAC-010 on tumor growth and metastasis were determined through tumor formation and metastasis imaging experiments in nude mice. RESULTS: The expression level of tRF-Val-CAC-010 was upregulated in A549 and PC9 LUAD cells (P < 0.01). Suppression of tRF-Val-CAC-010 expression resulted in decreased proliferation of A549 and PC9 cells (P < 0.001), reduced invasion and migration of A549 (P < 0.05, P < 0.001) and PC9 cells (P < 0.05, P < 0.01), enhanced apoptosis in both A549 (P < 0.05) and PC9 cells (P < 0.05), and increased G2 phase cell cycle arrest in A549 cells (P < 0.05). In vivo, the tumor formation volume in the tRF-inhibitor group was significantly smaller than that in the model and tRF-NC groups (P < 0.05). The metastatic tumor flux value in the tRF-inhibitor group was also significantly lower than that in the model and tRF-NC groups (P < 0.05). CONCLUSION: This study demonstrates that tRF-Val-CAC-010 promotes proliferation, migration, and invasion of LUAD cells and induces apoptosis in vitro, however, its specific effects on the cell cycle require further elucidation. Additionally, tRF-Val-CAC-010 enhances tumor formation and metastasis in vivo. Therefore, tRF-Val-CAC-010 may serve as a novel diagnostic biomarker and potential therapeutic target for LUAD.

Quantitative risk-benefit profiles of oral contraceptives, insulin sensitizers and antiandrogens for women with polycystic ovary syndrome: A model-based meta-analysis.

Oral contraceptives (OCs), insulin sensitizers, and antiandrogens (AAs), alone or in combination, are commonly used for treating non-fertility indications in polycystic ovary syndrome (PCOS). However, unclear risk-benefit profiles jeopardize their appropriate clinical applications. This study aimed to quantitatively evaluate the effects of the aforementioned medications and to compare their risk-benefit profiles. Randomized controlled trials published until 14th March 2022 were searched in PubMed and Embase. A model-based meta-analysis was developed to examine the time-effect profiles of each medication. The maximal percentage change of the effect (Emax) and time to achieve half of Emax (T50) were estimated. Primary outcomes included menstruation, hirsutism score, free androgen index (FAI), body mass index (BMI), insulin sensitivity, and lipid profiles. Overall, 200 studies (9,685 patients and 385 arms) were identified for modeling. OCs performed exceptionally well in improving menstruation (Emax: 149%; T50: 7.44 weeks), hirsutism score (Emax: 66.2%; T50: 26.2 weeks), and FAI (Emax: 75.7%; T50: 0.51 weeks). However, OCs elevated the triglyceride (TG) level (Emax: 12.6%; T50:1.19 weeks). After 12-week OC treatment, the TG level of approximately 30% of patients, whose baselines were normal, exceeded the reference limit. This suggested that OC-induced dyslipidemia should be routinely monitored. The maximal BMI-lowering effect of metformin was similar to that of placebo (Emax: 3.80%); however, metformin had a shorter T50 (6.67 weeks versus 12.9 weeks). Further, active lifestyle intervention plus placebo significantly decreased BMI (Emax: 8.78%). Adding metformin to active lifestyle intervention accelerated the BMI-lowering effect within 24 weeks, whereas with the extension of this addition beyond 24 weeks, BMI did not reduce further, which indicated that benefits were limited from this prolonged addition. AAs were less potent in reducing hirsutism score (Emax: 40.2% versus 66.2%) and FAI (Emax: 34.5% versus 75.7%) compared to OCs. OC plus metformin combined OC-derived androgen-suppressing effects and metformin-derived insulin-sensitizing effects, and partially relieved the OC-induced TG increase (Emax: 9.76%). Baseline dependency was found in most clinical responses, implying that pharmacotherapies tailored based on baselines achieved more clinical improvements. This study presents new quantitative evidence on pharmacotherapies for PCOS. Currently, long-term risk-benefit profiles and emerging therapies are inadequately reported and require more further research.

Estrogen-related receptor functions via the 20-hydroxyecdysone and IIS/TOR signaling pathways to regulate the development and morphology changes of ant Polyrhachis vicina Roger (Hymenoptera, Formicidae).

Estrogen-related receptor (ERR) is a key regulator of insect growth, development, and metabolic processes in insects; however, the molecular mechanisms underlying its effects are not fully understood. We investigated roles of 20-hydroxyecdysone (20E) and insulin/insulin-like signaling/target of rapamycin (IIS/TOR) signaling pathways in the effects of PvERR on larval development, metamorphosis, and adult growth in ant Polyrhachis vicina Roger. PvFOXO expression levels depended on caste and developmental stage. PvERR RNAi significantly reduced the expression levels of IIS/TOR signaling pathway genes and 20E signaling pathway genes in fourth-instar larvae, pupae, females, and workers and significantly increased the expression levels of IIS/TOR signaling pathway genes PvFOXO and PvAkt in males. PvFOXO RNAi resulted in developmental defects and increased mortality. After PvFOXO RNAi, the expression of PvERR, 20E signaling pathway genes, and IIS/TOR signaling pathway genes decreased significantly in pupae, females, and workers and increased significantly in fourth-instar larvae. Exogenous 20E attenuated expression changes induced by PvFOXO RNAi in a sex- and stage-specific manner. These results indicate that ERR interacts with 20E and IIS/TOR signaling pathways to regulate caste determination, metamorphosis, and male fertility in P. vicina and that correlations between PvERR and PvFOXO are caste- and stage-specific.

Feasibility analysis of rapid gene detection using intraoperative frozen tissues: comparison of intraoperative frozen tissues with paraffin-embedded tissues in epidermal growth factor receptor gene mutation detection of lung adenocarcinoma.

BACKGROUND: Epidermal growth factor receptor (EGFR) is the driver gene with the highest frequency of mutations in lung adenocarcinoma and can guide the development of targeted therapies. The detection of routine gene mutations must be performed after the preparation of paraffin samples in a standard polymerase chain reaction (PCR) laboratory, which is time-consuming. The Idylla™ EGFR fully automatic PCR system for rapid detection requires no special detection environment and completes the process in only 2.5 h. It has been applied to tissues embedded in paraffin. METHODS: The Idylla™ EGFR automated PCR system was used to detect EGFR gene mutations in intraoperative frozen fresh tissues and paraffin-embedded tissues from 47 enrolled patients with lung adenocarcinoma. The gold standard amplification refractory mutation system (ARMS) method for gene mutation detection was used for verification, and the concordance between the three detection results was compared, to investigate the feasibility of detecting rapid gene mutations in intraoperative frozen samples. RESULTS: The EGFR mutation rate in 47 fresh samples of lung adenocarcinoma was 61.7% (29/47), which is consistent with the mutation level of lung adenocarcinoma in the Asian population (38.8-64.0%). The concordance rate between the Idylla™ frozen tissues and paraffin-embedded tissues was 91.4% (43/47) when compared to the ARMS method, while the coincidence rate between the two methods was 93.6% (44/47). The three methods had a total consistency rate of 89.4% (42/47). CONCLUSIONS: The Idylla™ EGFR fully automatic PCR system directly detects EGFR mutations in fresh tissues. The operation is simple, the detection time is short, and the accuracy is high. The detection time is reduced to 1/4-1/3 of the original time while meeting clinical standards for detecting the gene status of patients, thus saving crucial time for individualized and accurate treatment of patients. The method has promising clinical application prospects.

A comparison of capillary electrophoresis and next-generation sequencing in the detection of immunoglobulin heavy chain H and light chain κ gene rearrangements in the diagnosis of classic hodgkin's lymphoma.

This study aimed to compare the application value of capillary electrophoresis and next-generation sequencing for immunoglobulin (IG) gene rearrangement in the diagnosis of classic Hodgkin's lymphoma. Twenty paraffin-embedded specimens from patients with classic Hodgkin's lymphoma were screened. For gene rearrangement detection, the ABI 3500 Genetic Analyzer and ABI Ion GeneStudio S5 Plus sequencing system were used, respectively, and the results were compared. Five cases with monoclonal rearrangements (25%, 5/20) were detected by Capillary Electrophoresis, and positivity for the FR1, FR2, FR3, and IGк loci was 5%, 10%, 10%, and 15%, respectively; 12 cases with monoclonal rearrangements (60%, 12/20) were detected by Next-generation Sequencing where the positivity of the above corresponding loci were 35%, 45%, 50%, and 30%, respectively. Among the 20 samples, 6 IGк clonal rearrangements were detected, and the usage frequency (66.7%) of IGкJ4 was the highest in the IGкJ subgroup. The usage frequency of IGкV1 and IGкV3 in the GкV sub-group was 33.3% and 33.3%, respectively. Twelve immunoglobulin heavy chain (IGH) clonal rearrangements were detected among the 20 samples, and the order of usage frequency in the IGH joining region J (IGHJ) subgroup was IGHJ4 > IGHJ5 > IGHJ6 > IGHJ3. The gene with the highest usage frequency in the IGH variable (IGHV) subgroup was IGHV3 (50%) and the percentage of IGHV mutations ranged from 0% ± 11.45% with an average frequency of 3.34%. Compared with Capillary Electrophoresis, Next-generation Sequencing showed a higher positivity in the detection of gene clonal rearrangements, was more accurate in the interpretation of results.

Vitellogenin regulates estrogen-related receptor expression by crosstalk with the JH and IIS-TOR signaling pathway in Polyrhachis vicina Roger (Hymenoptera, Formicidae).

The Estrogen-related receptor (ERR) can regulate the growth and development, metabolism, reproduction, and other physiological activities of insects, but its specific mechanism of action is still unclear. The aim of this study was to explore the relationship between expression of ERR and Vitellogenins (Vg) and the juvenile hormone (JH) and insulin/insulin-like growth factor/target of rapamycin (IIS/TOR) signaling pathways in Polyrhachis vicina Roger. P. vicina was used as the experimental model to clone the PvVg gene, perform double-stranded RNA synthesis and delivery and observe the effects of pharmacological treatments. The full-length PvVg cDNA product is 5586 bp. Higher PvVg mRNA expression was seen in the pupa and adults, and varying levels were seen in the different body parts of three different castes. RNA interference of PvVg expression led to disturbed development, an abnormal phenotype, and high mortality. PvVg RNAi also led to a reduction in mRNA levels of PvERR, ultraspiracle (PvUSP), forkhead box protein O (PvFOXO) and PvTOR genes in fourth instar larval, but a significant increase was seen in pupa and females. No significant change was seen in workers and males. After PvVg knockdown, application of exogenous JHIII reduced the expression of these genes in pupa and females, increased expression in workers, and decreased PvUSP mRNA expression in males. Both protein and mRNA expression levels of PvFOXO were affected by PvVg RNAi. PvERR RNAi increased PvVg expression in pupa and females and Kruppel-homolog 1 (PvKr-h1) and PvFOXO expression in males. The results of this study suggest that there is an interaction between PvERR and PvVg, and that crosstalk with the JH and IIS/TOR signaling pathways can affect development and reproduction. This effect is caste and developmental stage specific. We also speculate that the FOXO/USP complex participates in JH regulation of PvVg in P. vicina.

MicroRNA-26 regulates the expression of CTGF after exposure to ionizing radiation.

Radiation-induced fibrosis (RIF) is a serious complication that occurs after irradiation and which is caused by the deposition of extracellular matrix (ECM) proteins such as collagen. However, the underlying mechanisms, including the expression of the cytokines, that promote the RIF process, are not yet fully understood. MicroRNAs (miRNAs) have recently been suggested to act as post-transcriptional repressors for many genes; however, their role in the process of RIF remains to be elucidated. Our previous study showed that ionizing radiation increased the type I collagen expression through the activation of transforming growth factor (TGF)-ß, while miR-29 repressed this increase. This study aimed to investigate the mechanisms by which the expression of connective tissue growth factor (CTGF), a downstream mediator of TGF-ß, is controlled by miRNAs post-transcriptionally after exposure to ionizing radiation. The expression of CTGF in NIH-3T3 cells and mouse embryonic fibroblasts was increased by ionizing radiation. However, this increase was suppressed with a specific inhibitor of TGF-ß receptor. Among the predictable miRNAs that target the CTGF gene, the expression of miR-26a was downregulated after exposure to ionizing radiation and this regulation was negatively mediated by TGF-ß signaling. miR-26a negatively regulated the CTGF expression at the post-transcriptional level; however, ionizing radiation suppressed this negative regulation. In addition, the overexpression of miR-26a inhibited the expression of CTGF and type I collagen after irradiation. In conclusion, miR-26a modulates the expression of CTGF via TGF-ß signaling in irradiated fibroblasts. The results suggest the potential application of miR-26a in the treatment of RIF.

The LINC00365/SCGB2A1 (Mammaglobin B) Axis Down-Regulates NF-κB Signaling and Is Associated with the Progression of Gastric Cancer.

PURPOSE: A lack of early diagnostic biomarkers and therapeutic targets has led to poor prognosis for gastric cancer patients. However, the analysis of cancer-associated genomic data has been shown to be effective in identifying potential markers. Recently, the long non-coding RNA LINC00365 and SCGB2A1 gene (as known as mammaglobin B) were predicted to be co-expressed in gastric cancer based on the Gene Expression Omnibus database. However, their precise role in gastric cancer tumors is still not clear. METHODS: The expressions of LINC00365 and SCGB2A1 in gastric cancer tissues were investigated using qPCR and their expressions were detected in a gastric cancer tissue microarray by in situ hybridization and immunohistochemical staining. The functions of LINC00365 in BGC-823 and MGC-803 gastric cancer cells were tested using the MTT assay, flow cytometry, colony formation assay, EDU staining, immunofluorescence and luciferase assay. RESULTS: We found that LINC00365 and SCGB2A1 mRNA were both expressed at low levels in 30 cases of gastric cancer. Gastric cancer tissue microarray analysis indicated that LINC00365 and SCGB2A1 were expressed at low levels in tumor tissue, and low expression of both factors correlated with shorter survival time. Functional studies showed that LINC00365 overexpression significantly inhibited gastric cancer cell viability through the impairment of proliferation rather than the promotion of apoptosis. Furthermore, overexpressed LINC00365 upregulated SCGB2A1 in gastric cancer cell lines. Immuno-fluorescence and luciferase assay analysis indicated that LINC00365 overexpression inhibited the NF-κB pro-survival signaling pathway. Consistent with the effects of LINC00365, SCGB2A1 upregulation also reduced cell survival and inactivated NF-κB. CONCLUSION: Collectively, our findings revealed that SCGB2A1 may be the target coding protein regulated by LINC00365 in gastric cancer. LINC00365 and SCGB2A1 may function as tumor suppressors and may serve as potential prognostic and therapeutic markers in gastric cancer treatment.

Endometrial autophagy is essential for embryo implantation during early pregnancy.

Embryo implantation is an essential and complex process in mammalian reproduction. However, little evidence has indicated the involvement of autophagy during embryo implantation. To determine the possible role of autophagy in uterine of pregnant mice during the peri-implantation stage, we first examined the expression of autophagy-related markers ATG5 and LC3 on day 4, 5, and 6 of pregnancy (D4, D5, and D6, respectively). Compared with expression on D4, downregulation of the autophagy-related markers was observed on D5 and D6, the days after the embryo attached to the receptivity endometrium. Further examination showed that autophagy-related markers ATG5, ATG12, LC3, cathepsin B, and P62 at the implantation site were significantly decreased when comparing with the inter-implantation site. Fewer number of autophagosomes at the implantation site were also observed by transmission electron microscopy. To confirm the functional role of autophagy during embryo implantation in mice, we administered the autophagy inhibitor 3-methyladenine and chloroquine to mice. After treated with 3-methyladenine, the expression of decidual markers HOXA10 and progesterone receptor were significantly reduced. Furthermore, a reduction in implantation sites and increase in the HOXA10 and PR protein levels were observed in response to chloroquine treatment. In addition, impaired uterine decidualization and dysregulation of the PR and HOXA10 protein levels was observed after autophagy inhibited by 3-methyladenine and chloroquine in in vivo artificial decidualization mouse model. In the last, LC3 and P62 were also observed in normal human proliferative, secretory, and decidua tissues. In conclusion, endometrial autophagy may be essential for embryo implantation, and it may be associated with endometrial decidualization during early pregnancy. KEY MESSAGE: • Autophagy-related markers were significantly decreased at implantation site. • Autophagy inhibition results in abnormal decidualization. • Autophagy is essential for embryo implantation.

Phenotypic characterization of macrophages in the BMB sample of human acute leukemia.

Macrophages within tissues display a strong plastic ability in respond to environmental cues in both physiologic influences and disease. However, the macrophage phenotype and its distribution in the bone marrow biopsies (BMB) samples of human acute leukemia (AL) remain poorly understood. In this study, 97 BMB samples of patients with acute leukemia and 30 iron-deficiency anemias (IDA) as control group were evaluated with immunohistochemistry. In comparison with controls, the counts of CD68+, CD163+, and CD206+macrophages were remarkably increased in BMB samples of acute leukemia (P < 0.01), as well as their infiltration density was roaring up-regulation (P < 0.01). The expression levels of CD68+, CD163+, and CD206+macrophages were decreased in patients with complete remission, but there still existed statistically significant contrast to the control group (P < 0.01). The ratios of the CD163-positive cells or CD206-positive cells to CD68-positive cells were most prevalent in the BMB samples of human acute leukemia compared with the control group (P < 0.01), which support that macrophages were polarized to M2 macrophages.

MiRNA-574-3p inhibits cell progression by directly targeting CCND2 in colorectal cancer.

Colorectal cancer (CRC) remains the candidate for one of the typical types of malignant tumors of in gastrointestinal tract all around the world, which leads to tremendous death and ranks as the top leading death of cancer. Recently, microRNAs have emerged as double-edged sword in numerous cancers. This investigation aims to discuss the regulative role of microRNA-574-3p (miR-574-3p), elucidating its molecular mechanism and clinical significance in CRC. Herein, it revealed to us that miR-574-3p was lowly expressed in CRC tissues in comparison with the matched paracarcinoma tissues. In addition, transfection of SW480 and HT29 cells with miR-574-3p mimics prohibited the post-transcriptional expression of Cyclin D2 (CCND2), which then significantly blocked cell growth and cell migration, yet triggered cell apoptosis. Also, dual-luciferase reporter assays proved the role of CCND2 as the targeted gene for miR-574-3p. miR-574-3p overexpression prohibited the activity of CCND2 in SW480 and HT29 cells. Silencing of CCND2 in SW480 and HT29 CRC cell lines leading to reduced cell proliferative and migrative rates, and enhanced apoptotic rate. The suppressive effects of elevation of miR-574-3p on the proliferation of the human CRC cells and promotive effects on cell apoptosis by targeting CCND2 were further illustrated in the in vitro studies. Thus, we hypothesize that miR-574-3p may be served as a prospective therapeutic candidate for CRC.

Chaetomadrasins A and B, Two New Cytotoxic Cytochalasans from Desert Soil-Derived Fungus Chaetomium madrasense 375.

Two new cytochalasans, Chaetomadrasins A (1) and B (2), along with six known analogues (3-8), were isolated from the solid-state fermented culture of desert soil-derived Chaetomium madrasense 375. Their structures were clarified by comprehensive spectroscopic analyses, and the absolute configurations of Compounds 1 and 2 were confirmed by electronic circular dichroism (ECD) and calculated ECD. For the first time, Chaetomadrasins A (1), which belongs to the chaetoglobosin family, is characterized by the presence of all oxygen atoms in the form of Carbonyl. Chaetomadrasin B (2) represents the first example of chaetoglobosin type cytochalasan characterized by a hydroxy unit and carbonyl group fused to the indole ring. Compounds 1 and 2 displayed moderate cytotoxicity against HepG2 human hepatocellular carcinoma cells.

Morphological changes in different caste adult ant specificities of Polyrhachis vicina Roger (Hymenoptera, Formicidae) caused in estrogen-related receptor.

The estrogen-related receptor (ERR) gene is a member of the nuclear receptor subfamily. Previous studies have indicated that ERR plays important roles in regulating insect growth and development. How ERR is associated with ant caste specificities remains unclear. In this study, we attempted to identify the role of ERR in the regulation of different adult caste specificities of Polyrhachis vicina Roger. Significant variations were detected in the ants including PvERR expressions, some physiological indexes and morphological traits including survival rate, body weight, body length, head width and abdominal appearance by different techniques. The results revealed that when PvERR expressions is up-regulated, boundaries of the abdominal segments were indistinct on the ventral side of the abdomen in males. Down-regulation of PvERR expressions caused abdominal swelling in males and a distended ventral abdomen in females and workers. Variation in PvERR expressions led to a remarkable decline in ant survival rates, particularly for males. These results indicated that different caste adults appeared to have different degrees of sensitivity in physiological response and morphological changes caused by variation in PvERR expressions. Thus, our data demonstrate that PvERR plays an important role in regulating the different adult caste specificities of P. vicina.

SIRT3 aggravates metformin-induced energy stress and apoptosis in ovarian cancer cells.

Increasing evidence suggests that mitochondrial respiratory chain complex I participates in carcinogenesis and cancer progression by providing energy and maintaining mitochondrial function. However, the role of complex I in ovarian cancer is largely unknown. In this study we showed that metformin, considered to be an inhibitor of complex I, simultaneously inhibited cell growth and induced mitochondrial-related apoptosis in human ovarian cancer cells. Metformin interrupted cellular energy metabolism mainly by causing damage to complex I that impacted mitochondrial function. Additionally, treatment with metformin increased the activation of sirtuin 3 (SIRT3), a mitochondrial deacetylase. We demonstrated that SIRT3 overexpression aggravated metformin-induced apoptosis, energy stress and mitochondrial dysfunction. Moreover, treatment with metformin or SIRT3 overexpression increased activation of AMP-activated protein kinase (AMPK), a major sensor of cellular energy status. AMPK compensated for energy loss by increasing glycolysis. The impact of this was assessed by reducing glucose levels in the media or by using inhibitors (2-deoxyglucose, Compound C) of glycolysis and AMPK. The combination of these factors with metformin intensified cytotoxicity through further downregulation of ATP. Our study outlines an important role for SIRT3 in the antitumor effect of mitochondrial complex I inhibitors in human ovarian cancer cells. This effect appears to be mediated by induction of energy stress and apoptosis. Strategies that target the mitochondria could be enhanced by modulating glycolysis to further aggravate energy stress that may increase the antitumor effect.

Regulation of type I collagen expression by microRNA-29 following ionizing radiation.

Radiation-induced fibrosis (RIF) is thought to involve the excessive accumulation of collagen and other extracellular matrix components; previously, we reported that ionizing radiation increased the type I collagen expression and that transforming growth factor (TGF)-ß was involved in this increase through activating its downstream mediator, Smad3. A recent study found that microRNAs (miRNAs)-small, noncoding sequences approximately 20 nucleotides long-negatively regulate the gene expression posttranscriptionally, and it has been suggested that miRNAs play essential roles in cellular processes, including fibrosis. However, their role in the development of RIF remains unexplored. In the present study, we examined the effects of miRNA on the expression of type I collagen induced by ionizing radiation and the mechanisms underlying the miRNA expression observed following ionizing radiation. We analyzed the regulation of miRNA following ionizing radiation by an miRNA real-time PCR, and found that miR-29 family members were downregulated in irradiated mouse fibroblasts and directly targeted type I collagen genes by specifically binding to the 3' untranslated region. We also found that the overexpression of miR-29 inhibited the ionizing radiation-induced expression of type I collagen, whereas the knockdown of miR-29 enhanced it. In addition, TGF-ß/Smad-signaling significantly decreased the transcription of miR-29, whereas the inhibition of this signaling pathway cancelled this decrease. In conclusion, miR-29 was involved in the regulation of type I collagen expression through the TGF-ß/Smad-signaling pathway in irradiated cells, suggesting that miR-29 may be an important regulator of RIF.

Amycolamycins A and B, Two Enediyne-Derived Compounds from a Locust-Associated Actinomycete.

Two novel enediyne-derived natural products, amycolamycins A and B (1 and 2), were characterized from a locust-associated actinomycete Amycolatopsis sp. HCa4. Amycolamycins A and B contain a unique 2-(cyclopenta[a]inden-5-yl)oxirane core with suspected enediyne polyketide biosynthetic origin. Sequencing and analysis of the acm biosynthetic gene cluster allowed us to propose the biosynthetic pathway of 1 and 2. Moreover, amycolamycin A (1) was selectively cytotoxic to the M231 breast cancer cell line.

Cytoprotective Effect of the UCP2-SIRT3 Signaling Pathway by Decreasing Mitochondrial Oxidative Stress on Cerebral Ischemia-Reperfusion Injury.

Recovered blood supply after cerebral ischemia for a certain period of time fails to restore brain function, with more severe dysfunctional problems developing, called cerebral ischemia-reperfusion injury (CIR). CIR involves several extremely complex pathophysiological processes in which the interactions between key factors at various stages have not been fully elucidated. Mitochondrial dysfunction is one of the most important mechanisms of CIR. The mitochondrial deacetylase, sirtuin 3 (SIRT3), can inhibit mitochondrial oxidative stress by deacetylation, to maintain mitochondrial stability. Uncoupling protein 2 (UCP2) regulates ATP (Adenosine triphosphate) and reactive oxygen species production by affecting the mitochondrial respiratory chain, which may play a protective role in CIR. Finally, we propose that UCP2 regulates the activity of SIRT3 through sensing the energy level and, in turn, maintaining the mitochondrial steady state, which demonstrates a cytoprotective effect on CIR.

p62/SQSTM1 as an oncotarget mediates cisplatin resistance through activating RIP1-NF-κB pathway in human ovarian cancer cells.

Platinum-based therapeutic strategies have been widely used in ovarian cancer treatment. However, drug resistance has greatly limited therapeutic efficacy. Recently, tolerance to cisplatin has been attributed to other factors unrelated to DNA. p62 (also known as SQSTM1) functions as a multifunctional hub participating in tumorigenesis and may be a therapeutic target. Our previous study showed that p62 was overexpressed in drug-resistant ovarian epithelial carcinoma and its inhibition increased the sensitivity to cisplatin. In this study, we demonstrate that the activity of the NF-κB signaling pathway and K63-linked ubiquitination of RIP1 was higher in cisplatin-resistant ovarian (SKOV3/DDP) cells compared with parental cells. In addition, cisplatin resistance could be reversed by inhibiting the expression of p62 using siRNA. Furthermore, deletion of the ZZ domain of p62 that interacts with RIP1 in SKOV3 cells markedly decreased K63-linked ubiquitination of RIP1 and inhibited the activation of the NF-κB signaling pathway. Moreover, loss of the ZZ domain from p62 led to poor proliferative capacity and high levels of apoptosis in SKOV3 cells and made them more sensitive to cisplatin treatment. Collectively, we provide evidence that p62 is implicated in the activation of NF-κB signaling that is partly dependent on RIP1. p62 promotes cell proliferation and inhibits apoptosis thus mediating drug resistance in ovarian cancer cells.

Dimethyl sulfide protects against oxidative stress and extends lifespan via a methionine sulfoxide reductase A-dependent catalytic mechanism.

Methionine (Met) sulfoxide reductase A (MsrA) is a key endogenous antioxidative enzyme with longevity benefits in animals. Only very few approaches have been reported to enhance MsrA function. Recent reports have indicated that the antioxidant capability of MsrA may involve a Met oxidase activity that facilities the reaction of Met with reactive oxygen species (ROS). Herein, we used a homology modeling approach to search the substrates for the oxidase activity of MsrA. We found that dimethyl sulfide (DMS), a main metabolite that produced by marine algae, emerged as a good substrate for MsrA-catalytic antioxidation. MsrA bounds to DMS and promoted its antioxidant capacity via facilitating the reaction of DMS with ROS through a sulfonium intermediate at residues Cys72, Tyr103, and Glu115, followed by the release of dimethyl sulfoxide (DMSO). DMS reduced the antimycin A-induced ROS generation in cultured PC12 cells and alleviated oxidative stress. Supplement of DMS exhibited cytoprotection and extended longevity in both Caenorhabditis elegans and Drosophila. MsrA knockdown abolished the cytoprotective effect and the longevity benefits of DMS. Furthermore, we found that the level of physiologic DMS was at the low micromolar range in different tissues of mammals and its level decreased after aging. This study opened a new window to elucidate the biological role of DMS and other low-molecular sulfides in the cytoprotection and aging.

Evaluation of Transversus Abdominis Plane (TAP) Block in Hernia Surgery: A Meta-analysis.

BACKGROUND: Transversus abdominis plane (TAP) block reduces opiate requirements and pain scores in abdominal surgery, but the effect has not been evaluated in hernia surgery. The aim of this study was to evaluate the efficacy of TAP block in hernia surgery. METHODS: A meta-analysis of randomized clinical trials (RCTs) evaluating the effect of TAP block in adults undergoing hernia surgery was performed. The primary outcomes were morphine requirements 24 hours after surgery and the number of rescue analgesia patients. Secondary outcomes were pain scores on rest and on movement at 24 hours after surgery, postoperative nausea and vomiting and general postoperative complications. RESULTS: The search strategy yielded 231 articles after duplicates have been removed, and finally 8 RCTs with a total of 791 patients were included. In patients who received a TAP block, the cumulative morphine utilization was significantly reduced at 24 hours (weighted mean difference [WMD] -11.40 mg, -22.41 to -0.39; P=0.04). The number of patients needing a rescue analgesia (relative risk: 0.35, 0.22 to 0.55; P<0.001), the pain scores on rest 24 hours after surgery (WMD: -0.29, -0.55 to -0.04; P=0.02) and the pain scores on movement or coughing 24 hours after surgery (WMD: -0.70, -1.33 to -0.06; P=0.03) were all lower in patients who received a TAP block. There was also significant reduction in the postoperative nausea and vomiting, and the general postoperative complications in TAP block group. CONCLUSIONS: Within a heterogeneous group of RCTs, TAP block reduces postoperative morphine requirements and the severity of pain after hernia surgery.