DNA glycosylases provide antiviral defence in prokaryotes.

Bacteria have adapted to phage predation by evolving a vast assortment of defence systems1. Although anti-phage immunity genes can be identified using bioinformatic tools, the discovery of novel systems is restricted to the available prokaryotic sequence data2. Here, to overcome this limitation, we infected Escherichia coli carrying a soil metagenomic DNA library3 with the lytic coliphage T4 to isolate clones carrying protective genes. Following this approach, we identified Brig1, a DNA glycosylase that excises α-glucosyl-hydroxymethylcytosine nucleobases from the bacteriophage T4 genome to generate abasic sites and inhibit viral replication. Brig1 homologues that provide immunity against T-even phages are present in multiple phage defence loci across distinct clades of bacteria. Our study highlights the benefits of screening unsequenced DNA and reveals prokaryotic DNA glycosylases as important players in the bacteria-phage arms race.

Insurance Approval for Laparoscopic Sleeve Gastrectomy in Adolescents in the Midsouth.

Background: Metabolic and bariatric surgery (MBS) has been shown to be safe and effective for the treatment of adolescent obesity, yet many providers express hesitance to refer adolescents for surgery due to concerns for insufficient insurance coverage. Methods: The Healthy Lifestyle Clinic, a pediatric weight management clinic, was established in 2014, and an adolescent MBS program was added in 2017. Patients 15 years or older who meet the selection criteria are eligible for the surgery track. A retrospective chart review was conducted to describe our experience obtaining insurance approval for laparoscopic sleeve gastrectomy (LSG) for our adolescent patients. Results: Almost all patients who were interested in and eligible for LSG ultimately received insurance approval. Most patients had public insurance (70%). Sixty-four percent of patients were approved after the initial application, 23% were approved after a peer-to-peer review, and 11% required an appeal for approval. There was no difference in the time from insurance application to insurance approval based on age, race/ethnicity, or type of insurance. Conclusions: Age <18 years and having public health insurance have not been demonstrated as barriers to insurance approval for LSG in our cohort. Providers should not delay referral for MBS for eligible adolescents based on concern for insufficient insurance coverage. Adolescent MBS programs would benefit from a patient advocate to help families navigate the insurance approval process and reduce barriers to surgery.

Cancer-cell-secreted extracellular vesicles target p53 to impair mitochondrial function in muscle.

Skeletal muscle loss and weakness are associated with bad prognosis and poorer quality of life in cancer patients. Tumor-derived factors have been implicated in muscle dysregulation by inducing cachexia and apoptosis. Here, we show that extracellular vesicles secreted by breast cancer cells impair mitochondrial homeostasis and function in skeletal muscle, leading to decreased mitochondrial content and energy production and increased oxidative stress. Mechanistically, miR-122-5p in cancer-cell-secreted EVs is transferred to myocytes, where it targets the tumor suppressor TP53 to decrease the expression of TP53 target genes involved in mitochondrial regulation, including Tfam, Pgc-1α, Sco2, and 16S rRNA. Restoration of Tp53 in muscle abolishes mitochondrial myopathology in mice carrying breast tumors and partially rescues their impaired running capacity without significantly affecting muscle mass. We conclude that extracellular vesicles from breast cancer cells mediate skeletal muscle mitochondrial dysfunction in cancer and may contribute to muscle weakness in some cancer patients.

Increased MYBL2 expression in aggressive hormone-sensitive prostate cancer.

Loss of the histone demethylase KDM5D (lysine-specific demethylase 5D) leads to in vitro resistance of prostate cancer cells to androgen deprivation therapy (ADT) with and without docetaxel. We aimed to define downstream drivers of the KDM5D effect. Using chromatin immunoprecipitation sequencing (ChIP-seq) of the LNCaP cell line (androgen-sensitive human prostate adenocarcinoma) with and without silenced KDM5D, MYBL2-binding sites were analyzed. Associations between MYBL2 mRNA expression and clinical outcomes were assessed in cohorts of men with localized and metastatic hormone-sensitive prostate cancer. In vitro assays with silencing and overexpression of MYBL2 and KDM5D in androgen receptor (AR)-positive hormone-sensitive prostate cancer cell lines, LNCaP and LAPC4, were used to assess their influence on cellular proliferation, apoptosis, and cell cycle distribution, as well as sensitivity to androgen deprivation, docetaxel, and cabazitaxel. We found that silencing KDM5D increased histone H3 lysine K4 (H3K4) trimethylation and increased MYBL2 expression. KDM5D and MYBL2 were negatively correlated with some but not all clinical samples. Higher MYBL2 expression was associated with a higher rate of relapse in localized disease and poorer overall survival in men with metastatic disease in the CHAARTED trial. Lower MYBL2 levels enhanced LNCaP and LAPC4 sensitivity to androgen deprivation and taxanes. In vitro, modifications of KDM5D and MYBL2 altered cell cycle distribution and apoptosis in a cell line-specific manner. These results show that the transcription factor MYBL2 impacts in vitro hormone-sensitive prostate cancer sensitivity to androgen deprivation and taxanes, and lower levels are associated with better clinical outcomes in men with hormone-sensitive prostate cancer.

Bariatric surgery practice patterns among pediatric surgeons in the United States.

BACKGROUND: Metabolic and bariatric surgery (MBS) in adolescents has been shown to be safe and effective, but current practice patterns are variable and poorly understood. The aim of this study is to assess current MBS practice patterns among pediatric surgeons in the United States. METHODS: American Pediatric Surgical Association members were surveyed on current bariatric surgery practices. RESULTS: Four hundred and three (40%) surgeons out of a total of 1013 pediatric surgeons responded to the survey. Only 2 respondents had additional training in MBS (0.5%). One hundred thirty-two (32.6%) report that their practice participates in metabolic and bariatric surgery, with 123 (30.4%) having a specific partner specializing in MBS. Most respondents (92%) stated that they believe high volume is associated with better outcomes with regard to MBS. Only 17 (4.2%) surgeons performed a metabolic and bariatric surgery in the last year. All routinely perform sleeve gastrectomy as their primary procedure. Most (82%) perform procedures with an additional surgeon, either another pediatric surgeon (47%) or an adult bariatric surgeon (47%). All pediatric bariatric surgeons responded that they believe high volume led to better outcomes. Adolescent MBS programs most commonly included pediatric nutritionists (94%), pediatric psychologists (94%), clinical nurses (71%), clinical coordinators (59%), pediatric endocrinologists (59%), and exercise physiologists (52%). CONCLUSION: Only 17 (4.2%) respondents had performed a metabolic and bariatric surgery in the past year, and few of those had additional training in MBS. Future work is necessary to better understand optimal practice patterns for adolescent metabolic and bariatric surgery. TYPE OF STUDY: Review article. LEVEL OF EVIDENCE: Level III.

The Impact of PIK3R1 Mutations and Insulin-PI3K-Glycolytic Pathway Regulation in Prostate Cancer.

PURPOSE: Oncogenic alterations of the PI3K/AKT pathway occur in >40% of patients with metastatic castration-resistant prostate cancer, predominantly via PTEN loss. The significance of other PI3K pathway components in prostate cancer is largely unknown. EXPERIMENTAL DESIGN: Patients in this study underwent tumor sequencing using the MSK-IMPACT clinical assay to capture single-nucleotide variants, insertions, and deletions; copy-number alterations; and structural rearrangements, or were profiled through The Cancer Genome Atlas. The association between PIK3R1 alteration/expression and survival was evaluated using univariable and multivariable Cox proportional-hazards regression models. We used the siRNA-based knockdown of PIK3R1 for functional studies. FDG-PET/CT examinations were performed with a hybrid positron emission tomography (PET)/CT scanner for some prostate cancer patients in the MSK-IMPACT cohort. RESULTS: Analyzing 1,417 human prostate cancers, we found a significant enrichment of PIK3R1 alterations in metastatic cancers compared with primary cancers. PIK3R1 alterations or reduced mRNA expression tended to be associated with worse clinical outcomes in prostate cancer, particularly in primary disease, as well as in breast, gastric, and several other cancers. In prostate cancer cell lines, PIK3R1 knockdown resulted in increased cell proliferation and AKT activity, including insulin-stimulated AKT activity. In cell lines and organoids, PIK3R1 loss/mutation was associated with increased sensitivity to AKT inhibitors. PIK3R1-altered patient prostate tumors had increased uptake of the glucose analogue 18F-fluorodeoxyglucose in PET imaging, suggesting increased glycolysis. CONCLUSIONS: Our findings describe a novel genomic feature in metastatic prostate cancer and suggest that PIK3R1 alteration may be a key event for insulin-PI3K-glycolytic pathway regulation in prostate cancer.

A novel Lactobacillus bulgaricus isolate can maintain the intestinal health, improve the growth performance and reduce the colonization of E. coli O157:H7 in broilers.

1. This study aimed at the effects of a novel Lactobacillus bulgaricus (L. bulgaricus) strain and enterohemorrhagic Escherichia coli (E. coli) O157: H7 on intestinal flora and growth performance of broilers, and the protective effect of L. bulgaricus on broilers in challenged experiment by E. coli O157: H7.2. In vitro bacteriostatic test showed that the cell-free supernatant (CFS) of L. bulgaricus isolate had an obvious inhibitory effect on E. coli O157: H7.3. Eighty 1-day-old male broilers were randomly assigned into four treatment groups with four replicates per treatment. All groups received a basal diet in addition to the specific treatments: NC group, gavage with normal saline; In LBP group, gavage with L. bulgaricus isolate (1 × 109 CFU/mL) during the whole process and challenged with E. coli O157: H7 (3 × 109 CFU/mL); EC group, gavage with E. coli O157: H7 (3 × 109 CFU/mL); LB Group, gavage with L. bulgaricus isolate. At the age of 21 d, broilers were weighed and feed conversion ratio (FCR) was calculated. Caecum and caecal contents, ileum and faeces samples were taken after slaughter.4. The challenge of E. coli O157: H7 resulted in an increase in TLR-4, NF-κB and IL-8 mRNA in caecal tissue, a decrease in Villus: crypt ratio in ileum, a decrease in the overall diversity of intestinal microflora and a poor FCR.5. The L. bulgaricus isolate decreased the mRNA expression of TLR-4, NF-κB and IL-8 induced by E. coli O157: H7, reduced the content of E. coli O157: H7 in the caecum of broilers, increased the villus: crypt ratio, increased the abundance of beneficial bacteria and overall diversity of intestinal microflora, and improved FCR.6. The L. bulgaricus isolate can maintain the intestinal health, improve the growth performance of broilers and reduce the colonisation of E. coli O157:H7 in the caecum.

Prevalence of Upper Gastrointestinal Inflammation in Teens With Obesity Prior to Sleeve Gastrectomy.

INTRODUCTION: Upper gastrointestinal (UGI) pathologies are common in adolescents with obesity. This study aims to determine the prevalence of UGI inflammation on preoperative esophagogastroduodenoscopy (EGD) in adolescents undergoing sleeve gastrectomy (SG) and to assess weight loss outcomes. METHODS: This is a retrospective analysis of pathology reports from EGD biopsies performed prior to SG from September 2017 to August 2020. Percentage weight loss was measured at 3, 6, and 12 mo after surgery. Percent total body weight loss (TBWL) was compared between patients with and without UGI inflammation. RESULTS: Thirty adolescents underwent laparoscopic SG. Mean TBWL was 22% of total body weight 12 mo after surgery. Preoperative EGD identified 9 (30%) patients with esophagitis, 10 (33%) with gastritis, and 9 (30%) with duodenitis. Twenty-one patients (70%) had inflammation of at least one area, 5 (17%) were Helicobacter pylori positive, and 1 (3%) had a gastric ulcer that delayed surgery. Five (17%) patients were taking antacids prior to EGD. Patients with preoperative gastric or duodenal inflammation had significantly less TBWL 12 mo after SG compared to patients without gastric (24.6% versus 16.7%, P = 0.04) or duodenal inflammation (25.7% versus 14.1%, P = 0.02). CONCLUSIONS: There is a high prevalence of UGI inflammation in adolescents undergoing SG. Gastric and duodenal inflammation is associated with less TBWL after SG.

Inclusion and representation in the pediatric surgery workforce: Strategies to mitigate bias in the fellowship application process.

Diverse perspectives are critical components of effective teams in every industry. Underrepresentation of minorities in medicine leads to worse outcomes for minority patients, and efforts to increase diversity in the health care workforce are critical. Presently, about 70% of the pediatric surgery workforce is white, and pediatric surgeons at large do not reflect the racial or ethnic diversity of the populations they serve. Pediatric surgery fellowship training programs are the gateway to the field, and fellow selection processes should be optimized to support diversity and inclusion. The Association of Pediatric Surgery Training Program Directors (APSTPD) Diversity Equity and Inclusion subcommittee compiled best practices for bias mitigation during fellow selection, drawing from published literature and personal experiences in our own programs. A list of concrete recommendations was compiled, which can be implemented in every phase from applicant screening to rank list creation. We present these as a position statement that has been endorsed by the executive committee of the APSTPD. Pediatric surgery fellowship programs can utilize this focused review of best practices to mitigate bias and support diverse applicants.

Wavelength optimization for the laser treatment of port wine stains.

Based on the well-known principle of selective photothermolysis, laser has been a promising way for the treatment of port wine stains (PWSs). The laser wavelengths used for PWS's clinical treatment include but are not limited to pulsed dye laser (PDL) in 585-600 nm, long-pulse 755-nm alexandrite, and 1064-nm Nd:YAG lasers. The objective of this study was to investigate the optimal wavelength for PWS's laser treatment. A two-scale mathematic model was constructed to simultaneously quantify macroscale laser energy attenuation in two-layered bulk skin and microscale local energy absorption on target blood vessels within Krogh unit. The effects of morphological parameters, including epidermal melanin content, epidermal thickness, dermal blood content, blood vessel depth, and diameter on laser energy deposition within target blood vessels, were investigated from the visible to near-infrared bands (500-1100 nm). The energy deposition ratio of target blood vessel to epidermal surface was proposed to determine the optimal laser wavelength for PWS with different skin morphological parameters. The bioheat transfer modeling and animal experiment are also conducted to prove our wavelength optimization. The optimal wavelengths for lightly pigmented skin with small and shallow target blood vessels are 580-610 nm in the visible band. This wavelength coincides with commercially used PDL. The optimal wavelength shifts to 940 nm as the epidermal pigmentation increases or the size and blood vessel depth increases. The optimal wavelength changes to 1005 nm as the epidermal pigmentation or the size and burying depth of target blood vessel further increases. Nine hundred forty nanometers can be selected as a general wavelength in PWS treatment to meet the need in most widely morphological structure. Lasers with wavelengths in the 580-610, 940, and 1005 nm regions are effective for treating PWS because of their high optical selectivity in blood over the epidermis.

Dynamic expression of SNAI2 in prostate cancer predicts tumor progression and drug sensitivity.

Prostate cancer is a highly heterogeneous disease, understanding the crosstalk between complex genomic and epigenomic alterations will aid in developing targeted therapeutics. We demonstrate that, even though snail family transcriptional repressor 2 (SNAI2) is frequently amplified in prostate cancer, it is epigenetically silenced in this disease, with dynamic changes in SNAI2 levels showing distinct clinical relevance. Integrative clinical data from 18 prostate cancer cohorts and experimental evidence showed that gene fusion between transmembrane serine protease 2 (TMPRSS2) and ETS transcription factor ERG (ERG) (TMPRSS2-ERG fusion) is involved in the silencing of SNAI2. We created a silencer score to evaluate epigenetic repression of SNAI2, which can be reversed by treatment with DNA methyltransferase inhibitors and histone deacetylase inhibitors. Silencing of SNAI2 facilitated tumor cell proliferation and luminal differentiation. Furthermore, SNAI2 has a major influence on the tumor microenvironment by reactivating tumor stroma and creating an immunosuppressive microenvironment in prostate cancer. Importantly, SNAI2 expression levels in part determine sensitivity to the cancer drugs dasatinib and panobinostat. For the first time, we defined the distinct clinical relevance of SNAI2 expression at different disease stages. We elucidated how epigenetic silencing of SNAI2 controls the dynamic changes of SNAI2 expression that are essential for tumor initiation and progression and discovered that restoring SNAI2 expression by treatment with panobinostat enhances dasatinib sensitivity, indicating a new therapeutic strategy for prostate cancer.

Prognostic and therapeutic significance of COP9 signalosome subunit CSN5 in prostate cancer.

Chromosome 8q gain is associated with poor clinical outcomes in prostate cancer, but the underlying biological mechanisms remain to be clarified. CSN5, a putative androgen receptor (AR) partner that is located on chromosome 8q, is the key subunit of the COP9 signalosome, which deactivates ubiquitin ligases. Deregulation of CSN5 could affect diverse cellular functions that contribute to tumor development, but there has been no comprehensive study of its function in prostate cancer. The clinical significance of CSN5 amplification/overexpression was evaluated in 16 prostate cancer clinical cohorts. Its oncogenic activity was assessed by genetic and pharmacologic perturbations of CSN5 activity in prostate cancer cell lines. The molecular mechanisms of CSN5 function were assessed, as was the efficacy of the CSN5 inhibitor CSN5i-3 in vitro and in vivo. Finally, the transcription cofactor activity of CSN5 in prostate cancer cells was determined. The prognostic significance of CSN5 amplification and overexpression in prostate cancer was independent of MYC amplification. Inhibition of CSN5 inhibited its oncogenic function by targeting AR signaling, DNA repair, multiple oncogenic pathways, and spliceosome regulation. Furthermore, inhibition of CSN5 repressed metabolic pathways, including oxidative phosphorylation and glycolysis in AR-negative prostate cancer cells. Targeting CSN5 with CSN5i-3 showed potent antitumor activity in vitro and in vivo. Importantly, CSN5i-3 synergizes with PARP inhibitors to inhibit prostate cancer cell growth. CSN5 functions as a transcription cofactor to cooperate with multiple transcription factors in prostate cancer. Inhibiting CSN5 strongly attenuates prostate cancer progression and could enhance PARP inhibition efficacy in the treatment of prostate cancer.

Environmental conditions dictate differential evolution of vancomycin resistance in Staphylococcus aureus.

While microbiological resistance to vancomycin in Staphylococcus aureus is rare, clinical vancomycin treatment failures are common, and methicillin-resistant S. aureus (MRSA) strains isolated from patients after prolonged vancomycin treatment failure remain susceptible. Adaptive laboratory evolution was utilized to uncover mutational mechanisms associated with MRSA vancomycin resistance in a physiological medium as well as a bacteriological medium used in clinical susceptibility testing. Sequencing of resistant clones revealed shared and media-specific mutational outcomes, with an overlap in cell wall regulons (walKRyycHI, vraSRT). Evolved strains displayed similar properties to resistant clinical isolates in their genetic and phenotypic traits. Importantly, resistant phenotypes that developed in physiological media did not translate into resistance in bacteriological media. Further, a bacteriological media-specific mechanism for vancomycin resistance associated with a mutated mprF was confirmed. This study bridges the gap between the understanding of clinical and microbiological vancomycin resistance in S. aureus and expands the number of allelic variants (18 ± 4 mutations for the top 5 mutated genes) that result in vancomycin resistance phenotypes.

There is no dose-response relationship between allogeneic blood transfusion and healthcare-associated infection: a retrospective cohort study.

BACKGROUND: The association between allogeneic blood transfusion and healthcare-associated infection (HAI) is considered dose-dependent. However, this association may be confounded by transfusion duration, as prolonged hospitalization stay increases the risk of HAI. Also, it is not clear whether specific blood products have different dose-response risks. METHODS: In this retrospective cohort study, a logistic regression was used to identify confounding factors, and the association between specific blood products and HAI were analyzed. Then Cox regression and restricted cubic spline regression was used to visualize the hazard of HAI per transfusion product. RESULTS: Of 215,338 inpatients observed, 4.16% were transfused with a single component blood product. With regard to these transfused patients, 480 patients (5.36%) developed a HAI during their hospitalization stay. Logistic regression showed that red blood cells (RBCs) transfusion, platelets transfusion and fresh-frozen plasmas (FFPs) transfusion were risk factors for HAI [odds ratio (OR) 1.893, 95% confidence interval (CI) 1.656-2.163; OR 8.903, 95% CI 6.646-11.926 and OR 1.494, 95% CI 1.146-1.949, respectively]. However, restricted cubic spline regression analysis showed that there was no statistically dose-response relationship between different transfusion products and the onset of HAI. CONCLUSIONS: RBCs transfusion, platelets transfusion and FFPs transfusion were associated with HAI, but there was no dose-response relationship between them.

Attenuation of SRC Kinase Activity Augments PARP Inhibitor-mediated Synthetic Lethality in BRCA2-altered Prostate Tumors.

PURPOSE: Alterations in DNA damage repair (DDR) pathway genes occur in 20%-25% of men with metastatic castration-resistant prostate cancer (mCRPC). Although PARP inhibitors (PARPis) have been shown to benefit men with mCRPC harboring DDR defects due to mutations in BRCA1/2 and ATM, additional treatments are necessary because the effects are not durable. EXPERIMENTAL DESIGN: We performed transcriptomic analysis of publicly available mCRPC cases, comparing BRCA2 null with BRCA2 wild-type. We generated BRCA2-null prostate cancer cells using CRISPR/Cas9 and treated these cells with PARPis and SRC inhibitors. We also assessed the antiproliferative effects of combination treatment in 3D prostate cancer organoids. RESULTS: We observed significant enrichment of the SRC signaling pathway in BRCA2-altered mCRPC. BRCA2-null prostate cancer cell lines had increased SRC phosphorylation and higher sensitivity to SRC inhibitors (e.g., dasatinib, bosutinib, and saracatinib) relative to wild-type cells. Combination treatment with PARPis and SRC inhibitors was antiproliferative and had a synergistic effect in BRCA2-null prostate cancer cells, mCRPC organoids, and Trp53/Rb1-null prostate cancer cells. Inhibition of SRC signaling by dasatinib augmented DNA damage in BRCA2-null prostate cancer cells. Moreover, SRC knockdown increased PARPi sensitivity in BRCA2-null prostate cancer cells. CONCLUSIONS: This work suggests that SRC activation may be a potential mechanism of PARPi resistance and that treatment with SRC inhibitors may overcome this resistance. Our preclinical study demonstrates that combining PARPis and SRC inhibitors may be a promising therapeutic strategy for patients with BRCA2-null mCRPC.

Pediatric Spontaneous Pneumothorax: Does Initial Treatment Affect Outcomes?

BACKGROUND: Primary spontaneous pneumothorax (PSP) commonly occurs in adolescents, most commonly in males, and has recurrence rates between 20% and 60%. Surgical therapy has long been debated regarding its role in preventing recurrence, with no current consensus on guidelines for care. The purpose of this study is to examine the effect of treatment type on recurrence rates in pediatric PSP. METHODS: This is a single-institution, institutional review board-approved retrospective analysis of patients aged 1 to 18 diagnosed with their first occurrence of PSP between 2009 and 2017. Patient demographics, hospital course, and outcomes over a 2-y period were collected. Patients were divided into nonoperative (oxygen therapy only) management, chest tube placement, and surgical management. The primary outcome was the recurrence rate. RESULTS: Sixty-four patients diagnosed with PSP met inclusive criteria. The mean age was 15.5, and 48 (75%) of patients were men. Twenty-one patients (33%) underwent nonoperative treatment, 24 patients (37.5%) underwent operative treatment with video-assisted thoracoscopic surgery or open thoracotomy, and 19 patients (30%) underwent chest tube or pigtail placement alone. Fifteen patients (23.4%) experienced a recurrence within 2 y: 6 patients (29%) from the nonoperative treatment group, 4 (21%) who were treated with the chest tube only, and 5 (21%) who underwent video-assisted thoracoscopic surgery or open thoracotomy. No statistically significant difference in recurrence rates was found between treatment groups. Pneumothorax size was found to differ between treatment type; larger pneumothoraces were more likely to undergo surgical intervention (P = 0.0003). Smaller pneumothoraces were associated with higher rates of recurrence on multivariate logistic regression analysis (P = 0.046). CONCLUSIONS: Recurrence of PSP in adolescents was found to be 23.4% after 2-y follow-up. Smaller-sized pneumothoraces were associated with higher rates of recurrence, but treatment type did not significantly affect recurrence rates.

Ribonucleotide reductase small subunit M2 is a master driver of aggressive prostate cancer.

Although there are molecularly distinct subtypes of prostate cancer, no molecular classification system is used clinically. The ribonucleotide reductase small subunit M2 (RRM2) gene plays an oncogenic role in many cancers. Our previous study elucidated comprehensive molecular mechanisms of RRM2 in prostate cancer (PC). Given the potent functions of RRM2, we set out to determine whether the RRM2 signature can be used to identify aggressive subtypes of PC. We applied gene ontology and pathway analysis in RNA-seq datasets from PC cells overexpressing RRM2. We refined the RRM2 signature by integrating it with two molecular classification systems (PCS and PAM50 subtypes) that define aggressive PC subtypes (PCS1 and luminal B) and correlated signatures with clinical outcomes in six published cohorts comprising 4000 cases of PC. Increased expression of genes in the RRM2 signature was significantly correlated with recurrence, high Gleason score, and lethality of PC. Patients with high RRM2 levels showed higher PCS1 score, suggesting the aggressive PC feature. Consistently, RRM2-regulated genes were highly enriched in the PCS1 signature from multiple PC cohorts. A simplified RRM2 signature (12 genes) was identified by intersecting the RRM2 signature, PCS1 signature, and the PAM50 classifier. Intriguingly, inhibition of RRM2 specifically targets PCS1 and luminal B genes. Furthermore, 11 genes in the RRM2 signature were correlated with enzalutamide resistance by using a single-cell RNA-seq dataset from PC circulating tumor cells. Finally, high expression of RRM2 was associated with an immunosuppressive tumor-immune microenvironment in both primary prostate cancer and metastatic prostate cancer using CIBERSORT analysis and LM22, a validated leukocyte gene signature matrix. These data demonstrate that RRM2 is a driver of aggressive prostate cancer subtypes and contributes to immune escape, suggesting that RRM2 inhibition may be of clinical benefit for patients with PC.

Specific adsorption of tetracycline from milk by using biocompatible magnetic molecular imprinting material and evaluation by ECD.

Biocompatible magnetic molecularly imprinted polymers (BMMIPs) were prepared with Zein for the first time, and were used to enrich tetracycline compounds selectively. Innovative combination of BMMIPs and electrochemistry to obtain lower detection line to satisfy industrial detection demands. Using Zein as the crosslinking agent, the polymers were synthesized on the surface of Fe3O4 particles. The scanning electron microscope, transmission electron microscope and X-ray diffraction technologies were used to characterize BMMIPs. Through optimization, BMMIPs attained large adsorption capacity (236.40 mg/g) with fast kinetics (40 min) and followed the Langmuir isotherm and pseudo-second-order kinetic models. BMMIPs had good recognition ability, the selective factors of oxytetracycline, chlortetracycline, doxycycline were 4.78, 4.23, and 3.39, respectively. Excellent linearity was attained in the range of 0.025-500 µg/mL, with low detection limits and low quantitation limits of 0.025 and 0.083 µg/mL. According to our exploring, BMMIPs was ideal materials for enrichment of tetracycline in complex biological samples.

Experimental investigations on thermal effects of a long-pulse alexandrite laser on blood vessels and its comparison with pulsed dye and Nd:YAG lasers.

Laser has been widely used in the treatment of vascular skin diseases, such as port wine stain, due to the effect of selective photothermolysis in laser on biological tissue. The 755 nm alexandrite laser was expected to achieve better curative effect than the commonly used 585 or 595 nm pulsed dye laser (PDL) because of its deeper tissue penetration. In this study, the dorsal chamber model and microscopic visualization system were used to observe morphology changes on 42 blood vessels before and after irradiation with the 755 nm laser. Results showed that thermal effects of blood vessels intensified with the increase in energy, and high energy was required to produce the same thermal effect as the extension of pulse width. Different from 595 and 1064 nm lasers, partial vessel contraction was dominant thermal effect caused by the 755 nm laser. The bleeding injury rate and thermal effect of the 755 nm laser were between those of 595 nm PDL and 1064 nm Nd:YAG laser. The simulation results proved that 595 nm PDLs were effective for small and shallow target blood vessels. The 755 nm alexandrite lasers were effective in the treatment of hypertrophic and resistant blood vessels to PDL in the skin with low or moderate melanin concentration. The 1064 nm Nd:YAG laser was effective in the treatment of deeply buried and enlarged target blood vessels in the skin with high melanin concentration. The simulation results were supported by published clinical observations.

Significance of BRCA2 and RB1 Co-loss in Aggressive Prostate Cancer Progression.

PURPOSE: Previous sequencing studies revealed that alterations of genes associated with DNA damage response (DDR) are enriched in men with metastatic castration-resistant prostate cancer (mCRPC). BRCA2, a DDR and cancer susceptibility gene, is frequently deleted (homozygous and heterozygous) in men with aggressive prostate cancer. Here we show that patients with prostate cancer who have lost a copy of BRCA2 frequently lose a copy of tumor suppressor gene RB1; importantly, for the first time, we demonstrate that co-loss of both genes in early prostate cancer is sufficient to induce a distinct biology that is likely associated with worse prognosis. EXPERIMENTAL DESIGN: We prospectively investigated underlying molecular mechanisms and genomic consequences of co-loss of BRCA2 and RB1 in prostate cancer. We used CRISPR-Cas9 and RNAi-based methods to eliminate these two genes in prostate cancer cell lines and subjected them to in vitro studies and transcriptomic analyses. We developed a 3-color FISH assay to detect genomic deletions of BRCA2 and RB1 in prostate cancer cells and patient-derived mCRPC organoids. RESULTS: In human prostate cancer cell lines (LNCaP and LAPC4), loss of BRCA2 leads to the castration-resistant phenotype. Co-loss of BRCA2-RB1 in human prostate cancer cells induces an epithelial-to-mesenchymal transition, which is associated with invasiveness and a more aggressive disease phenotype. Importantly, PARP inhibitors attenuate cell growth in human mCRPC-derived organoids and human CRPC cells harboring single-copy loss of both genes. CONCLUSIONS: Our findings suggest that early identification of this aggressive form of prostate cancer offers potential for improved outcomes with early introduction of PARP inhibitor-based therapy.See related commentary by Mandigo and Knudsen, p. 1784.