Quorum sensing in bacteria: in silico protein analysis, ecophysiology, and reconstruction of their evolutionary history.

BACKGROUND: Quorum sensing (QS) is a sophisticated cell-to-cell signalling mechanism that allows the coordination of important processes in microbial populations. The AI-1 and AI-2 autoinducer systems are among the best characterized bacterial QS systems at the genetic level. RESULTS: In this study, we present data derived from in silico screening of QS proteins from bacterial genomes available in public databases. Sequence analyses allowed identifying candidate sequences of known QS systems that were used to build phylogenetic trees. Eight categories were established according to the number of genes from the two major QS systems present in each genome, revealing a correlation with specific taxa, lifestyles or metabolic traits. Many species had incomplete QS systems, encoding the receptor protein but not the biosynthesis of the quorum sensing molecule (QSMs). Reconstruction of the evolutionary history of the LuxR family and prediction of the 3D structure of the ancestral protein suggested their monomeric configuration in the absence of the signal molecule and the presence of a cavity for its binding. CONCLUSIONS: Here we correlate the taxonomic affiliation and lifestyle of bacteria from different genera with the QS systems encoded in their genomes. Moreover, we present the first ancestral reconstruction of the LuxR QS receptors, providing further insight in their evolutionary history.

Serum Tumor Markers and Outcomes in Patients With Appendiceal Adenocarcinoma.

Importance: Serum tumor markers carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), and cancer antigen 125 (CA125) have been useful in the management of gastrointestinal and gynecological cancers; however, there is limited information regarding their utility in patients with appendiceal adenocarcinoma. Objective: To assess the association of serum tumor markers (CEA, CA19-9, and CA125) with clinical outcomes and pathologic and molecular features in patients with appendiceal adenocarcinoma. Design, Setting, and Participants: This is a retrospective cohort study at a single tertiary care comprehensive cancer center. The median (IQR) follow-up time was 52 (21-101) months. Software was used to query the MD Anderson internal patient database to identify patients with a diagnosis of appendiceal adenocarcinoma and at least 1 tumor marker measured at MD Anderson between March 2016 and May 2023. Data were analyzed from January to December 2023. Main Outcomes and Measures: Association of serum tumor markers with survival in patients with appendiceal adenocarcinoma. Cox proportional hazards regression analyses were also performed to assess associations between clinical factors (serum tumor marker levels, demographics, and patient and disease characteristics) and patient outcomes (overall survival). Results: A total of 1338 patients with appendiceal adenocarcinoma were included, with a median (range) age at diagnosis of 56.5 (22.3-89.6) years. The majority of the patients had metastatic disease (1080 patients [80.7%]). CEA was elevated in 742 of the patients tested (56%), while CA19-9 and CA125 were elevated in 381 patients (34%) and 312 patients (27%), respectively. Individually, elevation of CEA, CA19-9, or CA125 were associated with worse 5-year survival; elevated vs normal was 81% vs 95% for CEA (hazard ratio [HR], 4.0; 95% CI, 2.9-5.6), 84% vs 92% for CA19-9 (HR, 2.2; 95% CI, 1.4-3.4), and 69% vs 93% for CA125 (HR, 4.6; 95% CI, 2.7-7.8) (P < .001 for all). Quantitative evaluation of tumor markers was associated with outcomes. Patients with highly elevated (top 10th percentile) CEA, CA19-9, or CA125 had markedly worse survival, with 5-year survival rates of 59% for CEA (HR, 9.8; 95% CI, 5.3-18.0), 64% for CA19-9 (HR, 6.0; 95% CI, 3.0-11.7), and 57% for CA125 (HR, 7.6; 95% CI, 3.5-16.5) (P < .001 for all). Although metastatic tumors had higher levels of all tumor markers, when restricting survival analysis to 1080 patients with metastatic disease, elevated CEA, CA19-9, or CA125 were all still associated worse survival (HR for CEA, 3.4; 95% CI, 2.5-4.8; P < .001; HR for CA19-9, 1.8; 95% CI, 1.2-2.7; P = .002; and HR for CA125, 3.9; 95% CI, 2.4-6.4; P < .001). Interestingly, tumor grade was not associated with CEA or CA19-9 level, while CA-125 was slightly higher in high-grade tumors relative to low-grade tumors (mean value, 18.3 vs 15.0; difference, 3.3; 95% CI, 0.9-3.7; P < .001). Multivariable analysis identified an incremental increase in the risk of death with an increase in the number of elevated tumor markers, with an 11-fold increased risk of death in patients with all 3 tumor markers elevated relative to those with none elevated. Somatic mutations in KRAS and GNAS were associated with significantly higher levels of CEA and CA19-9. Conclusions and Relevance: In this retrospective study of serum tumor markers in patients with appendiceal adenocarcinoma, CEA, CA19-9, and CA125 were associated with overall survival in appendiceal adenocarcinoma. Given their value, all 3 biomarkers should be included in the initial workup of patients with a diagnosis of appendiceal adenocarcinoma.

Deciphering the molecular components of the quorum sensing system in the fungus Ophiostoma piceae.

IMPORTANCE: This manuscript presents a comprehensive study on the molecular mechanisms triggered by the quorum sensing (QS) molecule farnesol in the biotechnologically relevant fungus Ophiostoma piceae. We present for the first time, using a multiomics approach, an in-depth analysis of the QS response in a saprotroph fungus, detailing the molecular components involved in the response and their possible mechanisms of action. We think that these results are particularly relevant in the knowledge of the functioning of the QS in eukaryotes, as well as for the exploitation of these mechanisms.

Prospective Observational Study of Prevalence, Assessment and Treatment of Pancreatic Exocrine Insufficiency in Patients with Inoperable Pancreatic Malignancy (PANcreatic Cancer Dietary Assessment-PanDA).

INTRODUCTION: Pancreatic exocrine insufficiency (PEI) in patients with advanced pancreatic cancer (aPC) is well documented, but there is no consensus regarding optimal screening. METHODS AND ANALYSIS: Patients diagnosed with aPC referred for palliative therapy were prospectively recruited. A full dietetic assessment (including Mid-Upper Arm Circumference (MUAC), handgrip and stair-climb test), nutritional blood panel, faecal elastase (FE-1) and 13C-mixed triglyceride breath tests were performed. PRIMARY OBJECTIVE: prevalence of dietitian-assessed PEI (demographic cohort (De-ch)); design (diagnostic cohort (Di-ch)) and validation (follow-up cohort (Fol-ch)) of a PEI screening tool. Logistic and Cox regressions were used for statistical analysis. RESULTS: Between 1 July 2018 and 30 October 2020, 112 patients were recruited (50 (De-ch), 25 (Di-ch) and 37 (Fol-ch)). Prevalence of PEI (De-ch) was 64.0% (flatus (84.0%), weight loss (84.0%), abdominal discomfort (50.0%) and steatorrhea (48.0%)). The derived PEI screening panel (Di-ch) included FE-1 (normal/missing (0 points); low (1 point)) and MUAC (normal/missing (>percentile 25) (0 points); low (2 points)) and identified patients at high-risk (2-3 total points) of PEI [vs. low-medium risk (0-1 total points)]. When patients from the De-ch and Di-ch were analysed together, those classified by the screening panel as "high-risk" had shorter overall survival (multivariable Hazard Ratio (mHR) 1.86 (95% CI 1.03-3.36); p-value 0.040). The screening panel was tested in the Fol-ch; 78.4% patients classified as "high-risk", of whom 89.6% had dietitian-confirmed PEI. The panel was feasible for use in clinical practice (64.8% patients completed all assessments), with high acceptability (87.5% would repeat it). Most patients (91.3%) recommended dietetic input for all patients with aPC. CONCLUSIONS: PEI is present in most patients with aPC; early dietetic input provides a holistic nutritional overview, including, but not limited to, PEI. This proposed screening panel may help to prioritise those at higher risk of PEI, requiring urgent dietitian input. Its prognostic role needs further validation.

Fungal-Lactobacteria Consortia and Enzymatic Catalysis for Polylactic Acid Production.

Polylactic acid (PLA) is the main biobased plastic manufactured on an industrial scale. This polymer is synthetized by chemical methods, and there is a strong demand for the implementation of clean technologies. This work focuses on the microbial fermentation of agro-industrial waste rich in starch for the production of lactic acid (LA) in a consolidated bioprocess, followed by the enzymatic synthesis of PLA. Lactic acid bacteria (LAB) and the fungus Rhizopus oryzae were evaluated as natural LA producers in pure cultures or in fungal-lactobacteria co-cultures formed by an LAB and a fungus selected for its metabolic capacity to degrade starch and to form consortia with LAB. Microbial interaction was analyzed by scanning electron microscopy and biofilm production was quantified. The results show that the fungus Talaromyces amestolkiae and Lactiplantibacillus plantarum M9MG6-B2 establish a cooperative relationship to exploit the sugars from polysaccharides provided as carbon sources. Addition of the quorum sensing molecule dodecanol induced LA metabolism of the consortium and resulted in improved cooperation, producing 99% of the maximum theoretical yield of LA production from glucose and 65% from starch. Finally, l-PLA oligomers (up to 19-LA units) and polymers (greater than 5 kDa) were synthetized by LA polycondensation and enzymatic ring-opening polymerization catalyzed by the non-commercial lipase OPEr, naturally produced by the fungus Ophiostoma piceae.

The Mental Health Burden of Patients with Colorectal Cancer Receiving Care during the COVID-19 Pandemic: Results of the PICO-SM Study.

The COVID-19 pandemic has resulted in unprecedented changes to the lives of patients with cancer. To evaluate the impact of the COVID-19 pandemic on the mental health and well-being of patients with colorectal cancer, we conducted a prospective longitudinal questionnaire study at a UK tertiary cancer centre. In total, 216 participants were included: mean age 65 years, 57% (n = 122) male, 92% (n = 198) of white ethnicity. Amongst participants who completed the screening psychometric questionnaire, 24% (n = 48/203) reported anxiety (GAD-7 ≥ 5), 15% (n = 31/204) depressive symptoms (PHQ-9 ≥ 10), 3% (n = 5/190) probable post-traumatic stress disorder (PC-PTSD-5 ≥ 4), and 31% (n = 66/213) poor well-being (WHO-5 < 50). In the subgroup (n = 95/216, 44%) who consented to and completed a follow-up survey 6 months later, there was a significant increase in the number of participants at risk of depression (4% vs. 13%, p = 0.021). Self-reported concern about the COVID-19 pandemic impacting one's mental health is associated with increased likelihood of anxiety, depression, and poor well-being, in respective multivariate analyses. In conclusion, screening for the mental health impact of the COVID-19 pandemic is essential to ensure timely action from all key stakeholders and to avoid potentially longer-term detrimental consequences.

RAS Mutation Status Should Not Be Used to Predict Outcome from Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases.

BACKGROUND: Genetic biomarkers guide systemic anti-cancer treatment (SACT) in metastatic colorectal cancer. It has been suggested they have a role in selecting patients with colorectal peritoneal metastases (CRPM) for cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). This study aims to quantify the effect of mutation status on overall survival (OS), adjusting for confounders such as pre-operative systemic anticancer treatment (SACT). PATIENTS AND METHODS: Retrospective analysis of patients undergoing CRS/HIPEC for CRPM at a national peritoneal tumour centre (2004-2017) was performed. Demographics, treatment history and operative data were extracted. Known biomarker gene mutation status was noted including: KRAS, NRAS, BRAF, PIK3CA and MMR. Cox regression analysis and Kaplan-Meier curves were used to determine overall survival. RESULTS: One hundred ninety-five patients were included. Median follow-up time was 34.7 months (range 5.4-184.9 months) and median OS was 38.7 months (95% CI 32.4-44.9 months). Biomarker status was as follows: KRAS (n = 114), NRAS (n = 85), BRAF (n = 44), PIK3CA (n = 15) and MMR (n = 21). Mutation rates were 45.6%, 3.5%, 13.6%, 13.3% and 14.3%, respectively. Seventy-four per cent underwent complete cytoreduction (CC = 0), 81% received SACT pre-CRS/HIPEC and 65% post-CRS/HIPEC. RAS (p = 0.21) or BRAF (p = 0.109) mutation status did not predict OS. Nodal involvement, extramural vascular invasion, Peritoneal Cancer Index (PCI) score, CC score, SACT post-HIPEC and NRAS mutation were significant negative predictors of OS in univariate analysis (p < 0.05). Multivariate Cox regression confirmed CC-score > 1 (HR: 7.599, 95% CI 3.402-16.974, p < 0.0001) as a negative predictor of OS. RAS mutation status did not affect outcome (HR: 1.682, 95% CI 0.995-2.843, p = 0.052). CONCLUSIONS: RAS mutation status should not in isolation be used to select patients for CRS/HIPEC.

The intestinal microbiota in colorectal cancer metastasis - Passive observer or key player?

The association between colorectal cancer (CRC) and alterations in intestinal microbiota has been demonstrated by several studies, and there is increasing evidence that bacteria are an important component of the tumour microenvironment. Bacteria may contribute to the development of CRC metastasis by signalling through metabolites, promoting epithelial-mesenchymal transition, creating an immunosuppressive microenvironment and through the impairment of the gut-vascular barrier. Host immunity and intestinal microbiome symbiosis play a key role in determining innate and adaptive immune responses at the local and systemic level. How this gut-systemic axis might contribute to the development of CRC metastasis is however unclear. Several clinical trials are investigating the impact of microbiome-targeted interventions on the systemic inflammatory response, treatment-related complications, and side effects. This review examines pre-clinical and clinical studies which have examined the role of microbes in relation to CRC metastasis, the mechanisms which may contribute to tumour dissemination, and directions for future work.

Management of incidentally discovered appendiceal neuroendocrine tumors after an appendicectomy.

Appendiceal neuroendocrine tumors (aNETs) are an uncommon neoplasm that is relatively indolent in most cases. They are typically diagnosed in younger patients than other neuroendocrine tumors and are often an incidental finding after an appendectomy. Although there are numerous clinical practice guidelines on management of aNETs, there is continues to be a dearth of evidence on optimal treatment. Management of these tumors is stratified according to risk of locoregional and distant metastasis. However, there is a lack of consensus regarding tumors that measure 1-2 cm. In these cases, some histopathological features such as size, tumor grade, presence of lymphovascular invasion, or mesoappendix infiltration must also be considered. Computed tomography or magnetic resonance imaging scans are recommended for evaluating the presence of additional disease, except in the case of tumors smaller than 1 cm without additional risk factors. Somatostatin receptor scintigraphy or positron emission tomography with computed tomography should be considered in cases with suspected residual or distant disease. The main point of controversy is the indication for performing a completion right hemicolectomy after an initial appendectomy, based on the risk of lymph node metastases. The main factor considered is tumor size and 2 cm is the most common threshold for indicating a colectomy. Other factors such as mesoappendix infiltration, lymphovascular invasion, or tumor grade may also be considered. On the other hand, potential complications, and decreased quality of life after a hemicolectomy as well as the lack of evidence on benefits in terms of survival must be taken into consideration. In this review, we present data regarding the current indications, outcomes, and benefits of a colectomy.

Genome sequence and Carbohydrate Active Enzymes (CAZymes) repertoire of the thermophilic Caldicoprobacter algeriensis TH7C1T.

BACKGROUND: Omics approaches are widely applied in the field of biology for the discovery of potential CAZymes including whole genome sequencing. The aim of this study was to identify protein encoding genes including CAZymes in order to understand glycans-degrading machinery in the thermophilic Caldicoprobacter algeriensis TH7C1T strain. RESULTS: Caldicoprobacter algeriensis TH7C1T is a thermophilic anaerobic bacterium belonging to the Firmicutes phylum, which grows between the temperatures of 55 °C and 75 °C. Next generation sequencing using Illumina technology was performed on the C. algeriensis strain resulting in 45 contigs with an average GC content of 44.9% and a total length of 2,535,023 bp. Genome annotation reveals 2425 protein-coding genes with 97 ORFs coding CAZymes. Many glycoside hydrolases, carbohydrate esterases and glycosyltransferases genes were found linked to genes encoding oligosaccharide transporters and transcriptional regulators; suggesting that CAZyme encoding genes are organized in clusters involved in polysaccharides degradation and transport. In depth analysis of CAZomes content in C. algeriensis genome unveiled 33 CAZyme gene clusters uncovering new enzyme combinations targeting specific substrates. CONCLUSIONS: This study is the first targeting CAZymes repertoire of C. algeriensis, it provides insight to the high potential of identified enzymes for plant biomass degradation and their biotechnological applications.

A Fungal Versatile GH10 Endoxylanase and Its Glycosynthase Variant: Synthesis of Xylooligosaccharides and Glycosides of Bioactive Phenolic Compounds.

The study of endoxylanases as catalysts to valorize hemicellulosic residues and to obtain glycosides with improved properties is a topic of great industrial interest. In this work, a GH10 ß-1,4-endoxylanase (XynSOS), from the ascomycetous fungus Talaromyces amestolkiae, has been heterologously produced in Pichia pastoris, purified, and characterized. rXynSOS is a highly glycosylated monomeric enzyme of 53 kDa that contains a functional CBM1 domain and shows its optimal activity on azurine cross-linked (AZCL)-beechwood xylan at 70 °C and pH 5. Substrate specificity and kinetic studies confirmed its versatility and high affinity for beechwood xylan and wheat arabinoxylan. Moreover, rXynSOS was capable of transglycosylating phenolic compounds, although with low efficiencies. For expanding its synthetic capacity, a glycosynthase variant of rXynSOS was developed by directed mutagenesis, replacing its nucleophile catalytic residue E236 by a glycine (rXynSOS-E236G). This novel glycosynthase was able to synthesize ß-1,4-xylooligosaccharides (XOS) of different lengths (four, six, eight, and ten xylose units), which are known to be emerging prebiotics. rXynSOS-E236G was also much more active than the native enzyme in the glycosylation of a broad range of phenolic compounds with antioxidant properties. The interesting capabilities of rXynSOS and its glycosynthase variant make them promising tools for biotechnological applications.

Molecular Profiling of Well-Differentiated Neuroendocrine Tumours: The Role of ctDNA in Real-World Practice.

Background: The role of tumour genomic profiling in the clinical management of well-differentiated neuroendocrine tumours (WdNETs) is unclear. Circulating tumour DNA (ctDNA) may be a useful surrogate for tumour tissue when the latter is insufficient for analysis. Methods: Patients diagnosed with WdNETs underwent ctDNA genomic profiling (FoundationLiquid®); non-WdNETs (paraganglioma, goblet cell or poorly-differentiated neuroendocrine carcinoma) were used for comparison. The aim was to determine the rate of: test failure (primary end-point), "pathological alterations" (PAs) (secondary end-point) and patients for whom ctDNA analysis impacted management (secondary end-point). Results: Forty-five patients were included. A total of 15 patients with WdNETs (18 ctDNA samples) were eligible: 8 females (53.3%), median age 63.2 years (range 23.5-86.8). Primary: small bowel (8; 53.3%), pancreas (5; 33.3%), gastric (1; 6.7%) and unknown primary (1; 6.7%); grade (G)1 (n = 5; 33.3%), G2 (9; 60.0%) and G3 (1; 6.7%); median Ki-67: 5% (range 1-30). A total of 30 patients with non-WdNETs (34 ctDNA samples) were included. Five WdNETs samples (27.78%) failed analysis (vs. 17.65% in non-WdNETs; p-value 0.395). Of the 13 WdNET samples with successful ctDNA analyses, PAs were detected in 6 (46.15%) (vs. 82.14% in non-WdNETs; p-value 0.018). In WdNETs, the PA rate was independent of concomitant administration anti-cancer systemic therapies (2/7; 28.57% vs. 4/6; 66.67%; p-value 0.286) at the time of the ctDNA analysis: four, one and one samples had one, two and three PAs, respectively. These were: CDKN2A mutation (mut) (one sample), CHEK2mut (one), TP53mut (one), FGFR2 amplification (one), IDH2mut (one), CTNNB1mut (one), NF1mut (one) and PALB2mut (one). None were targetable (0%) or impacted clinical management (0%). There was a lower maximum mutant allele frequency (mMAF) in WdNETs (mean 0.33) vs. non-WdNETs (mean 26.99), even though differences did not reach statistical significance (p-value 0.0584). Conclusions: Although feasible, mutation-based ctDNA analysis was of limited clinical utility for patients with advanced WdNETs. The rates of PAs and mMAFs were higher in non-WdNETs. While patients with WdNETs could still be offered genomic profiling (if available and reimbursed), it is important to manage patients' expectations regarding the likelihood of the results impacting their treatment.

External Validity of Somatostatin Analogs Trials in Advanced Neuroendocrine Neoplasms: The GETNE-TRASGU Study.

INTRODUCTION: Somatostatin analogs (SSA) prolong progression-free survival (PFS) in patients with well-differentiated gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). However, the eligibility criteria in randomized clinical trials (RCTs) have been restricted, which contrasts with the vast heterogeneity found in NENs. METHODS: We identified patients with well-differentiated (Ki-67% ≤20%), metastatic GEP-NENs treated in first line with SSA monotherapy from the Spanish R-GETNE registry. The therapeutic effect was evaluated using a Bayesian Cox model. The objective was to compare survival-based outcomes from real-world clinical practice versus RCTs. RESULTS: The dataset contained 535 patients with a median age of 62 years (range: 26-89). The median Ki-67% was 4 (range: 0-20). The most common primary tumor sites were as follows: midgut, 46%; pancreas, 34%; unknown primary, 10%; and colorectal, 10%. Half of the patients received octreotide LAR (n = 266) and half, lanreotide autogel (n = 269). The median PFS was 28.0 months (95% CI: 22.1-32.0) for octreotide versus 30.1 months (95% CI: 23.1-38.0) for lanreotide. The overall hazard ratio for lanreotide versus octreotide was 0.90 (95% credible interval: 0.71-1.12). The probability of effect sizes >30% with lanreotide versus octreotide was 2 and 6% for midgut and foregut NENs, respectively. CONCLUSION: Our study evaluated the external validity of RCTs examining SSAs in the real world, as well as the main effect-modifying factors (progression status, symptoms, tumor site, specific metastases, and analytical data). Our results indicate that both octreotide LAR and lanreotide autogel had a similar effect on PFS. Consequently, both represent valid alternatives in patients with well-differentiated, metastatic GEP-NENs.

Modification to Systemic Anticancer Therapy at the Start of the COVID-19 Pandemic and its Overall Impact on Survival Outcomes in Patients with Colorectal Cancer.

BACKGROUND: Since the beginning of the COVID-19 pandemic, multiple changes to the provision of cancer care has been introduced to maximize patient safety and protect staff. We aimed to identify factors influencing clinicians' decision on treatment modification during the initial phase of the pandemic, and to assess its impact on outcomes in patients with colorectal cancer. PATIENTS AND METHODS: Electronic records of patients seen in a large United Kingdom tertiary cancer center was reviewed. The frequency and type of changes to systemic anticancer therapy , as well as the factors predicting clinicians' decision were assessed. RESULTS: A total of 418 patients; mean age 63 ± 12 years and 57% male were included. More than half of the patients had modification to their treatment; with treatment delay (21%) or cancellation (10%), being the most common. Majority of patients on neoadjuvant treatment (97%) proceeded with treatment, with some form of treatment modification in 20%. Half of patients on adjuvant treatment had their treatment plan modified. Overall, a change in treatment was more likely in older patients (OR 1.028 [95% CI 1.010-1.047]; P = .002), and in patients who had already received higher number of cycles of systemic anticancer therapy (OR 1.040 [95% CI 1.016-1.065]; P = .001). A change in treatment was less likely further out of the first national lockdown (OR 0.837 [95% CI 0.758-0.925]; P < .001). Patients on third-line treatment were most likely to have alterations to their treatment plan (69%, n=33/48). CONCLUSION: During the first wave of COVID-19 in the United Kingdom, clinicians adapted clinical practice in accordance to local and national guidance, especially amongst older patients and those on third-line treatment. Further real-world data are needed to document the important impact of changes to treatment on outcomes in patients with cancer.

Synthesis and Characterization of a Novel Resveratrol Xylobioside Obtained Using a Mutagenic Variant of a GH10 Endoxylanase.

Resveratrol is a natural polyphenol with antioxidant activity and numerous health benefits. However, in vivo application of this compound is still a challenge due to its poor aqueous solubility and rapid metabolism, which leads to an extremely low bioavailability in the target tissues. In this work, rXynSOS-E236G glycosynthase, designed from a GH10 endoxylanase of the fungus Talaromyces amestolkiae, was used to glycosylate resveratrol by using xylobiosyl-fluoride as a sugar donor. The major product from this reaction was identified by NMR as 3-O-ꞵ-d-xylobiosyl resveratrol, together with other glycosides produced in a lower amount as 4'-O-ꞵ-d-xylobiosyl resveratrol and 3-O-ꞵ-d-xylotetraosyl resveratrol. The application of response surface methodology made it possible to optimize the reaction, producing 35% of 3-O-ꞵ-d-xylobiosyl resveratrol. Since other minor glycosides are obtained in addition to this compound, the transformation of the phenolic substrate amounted to 70%. Xylobiosylation decreased the antioxidant capacity of resveratrol by 2.21-fold, but, in return, produced a staggering 4,866-fold improvement in solubility, facilitating the delivery of large amounts of the molecule and its transit to the colon. A preliminary study has also shown that the colonic microbiota is capable of releasing resveratrol from 3-O-ꞵ-d-xylobiosyl resveratrol. These results support the potential of mutagenic variants of glycosyl hydrolases to synthesize highly soluble resveratrol glycosides, which could, in turn, improve the bioavailability and bioactive properties of this polyphenol.

Developing an Agnostic Risk Prediction Model for Early AKI Detection in Cancer Patients.

Acute kidney injury (AKI) is a common complication among oncology patients associated with lower remission rates and higher mortality. To reduce the impact of this condition, we aimed to predict AKI earlier than existing tools, to allow clinical intervention before occurrence. We trained a random forest model on 597,403 routinely collected blood test results from 48,865 patients undergoing cancer treatment at The Christie NHS Foundation Trust between January 2017 and May 2020, to identify AKI events upcoming in the next 30 days. AKI risk levels were assigned to upcoming AKI events and tested through a prospective analysis between June and August 2020. The trained model gave an AUROC of 0.881 (95% CI 0.878-0.883), when assessing predictions per blood test for AKI occurrences within 30 days. Assigning risk levels and testing the model through prospective validation from the 1st June to the 31st August identified 73.8% of patients with an AKI event before at least one AKI occurrence, 61.2% of AKI occurrences. Our results suggest that around 60% of AKI occurrences experienced by patients undergoing cancer treatment could be identified using routinely collected blood results, allowing clinical remedial action to be taken and disruption to treatment by AKI to be minimised.

Systematic Roadmap for Cancer Drug Screening Using Zebrafish Embryo Xenograft Cancer Models: Melanoma Cell Line as a Case Study.

Zebrafish embryo tumor transplant models are widely utilized in cancer research. Compared with traditional murine models, the small size and transparency of zebrafish embryos combined with large clutch sizes that increase statistical power and cheap husbandry make them a cost-effective and versatile tool for in vivo drug discovery. However, the lack of a comprehensive analysis of key factors impacting the successful use of these models impedes the establishment of basic guidelines for systematic screening campaigns. Thus, we explored the following crucial factors: (i) user-independent inclusion criteria, focusing on sample homogeneity; (ii) metric definition for data analysis; (iii) tumor engraftment criteria; (iv) image analysis versus quantification of human cancer cells using qPCR (RNA and gDNA); (v) tumor implantation sites; (vi) compound distribution (intratumoral administration versus alternative inoculation sites); and (vii) efficacy (intratumoral microinjection versus compound solution in media). Based on these analyses and corresponding assessments, we propose the first roadmap for systematic drug discovery screening in zebrafish xenograft cancer models using a melanoma cell line as a case study. This study aims to help the wider cancer research community to consider the adoption of this versatile model for cancer drug screening projects.

Fungal glycosyl hydrolases for sustainable plant biomass valorization: Talaromyces amestolkiae as a model fungus.

As the main decomposers and recyclers in nature, fungi secrete complex mixtures of extracellular enzymes for degradation of plant biomass, which is essential for mobilization of the organic carbon fixed by the photosynthesis in vegetal cells. Biotechnology can emulate the closed natural biological cycles, using lignocellulosic biomass as a renewable resource and lignocellulolytic fungal enzymes as catalysts to sustainably produce consumer goods. Cellulose and hemicellulose are the major polysaccharides on Earth, and the main enzymes involved in their hydrolytic depolymerization are cellulases (endoglucanases, cellobiohydrolases, and ß-glucosidases) and hemicellulases (mainly endoxylanases and ß-xylosidases). This work will focus on the enzymes secreted by the filamentous ascomycete Talaromyces amestolkiae and on some of their biotechnological applications. Their excellent hydrolytic activity was demonstrated by the partial degradation of xylans to prebiotic oligosaccharides by the endoxylanase XynN, or by the saccharification of lignocellulosic wastes to monosaccharides (fermentable to ethanol) either by the whole secretomes or by isolated enzymes used as supplements of commercial cocktails. However, apart from their expected hydrolytic activity, some of the ß-glycosidases produced by this strain catalyze the transfer of a sugar molecule to specific aglycons by transglycosylation. As the synthesis of customized glycoconjugates is a major goal for biocatalysis, mutant variants of the ß-xyloxidase BxTW1 and the ß-glucosidases BGL-1 and BGL-2 were obtained by directed mutagenesis, substantially improving the regioselective production yields of bioactive glycosides since they showed reduced or null hydrolytic activity.