Targeting Glutathione and Cystathionine β-Synthase in Ovarian Cancer Treatment by Selenium-Chrysin Polyurea Dendrimer Nanoformulation

The research was funded by iNOVA4Health UID/Multi/04462, a program financially supported by Fundação para a Ciência e Tecnologia/Ministério da Educação e Ciência (FCT-MCTES), through national funds, and co-funded by FEDER under the PT2020 Partnership Agreement. We also acknowledge funding from FCT-MCTES through project DREAM PTDC/MEC-ONC/29327/2017.Ovarian cancer is the main cause of death from gynecological cancer, with its poor prognosis mainly related to late diagnosis and chemoresistance (acquired or intrinsic) to conventional alkylating and reactive oxygen species (ROS)-generating drugs. We and others reported that the availability of cysteine and glutathione (GSH) impacts the mechanisms of resistance to carboplatin in ovarian cancer. Different players in cysteine metabolism can be crucial in chemoresistance, such as the cystine/glutamate antiporter system Xc (xCT) and the H2S-synthesizing enzyme cystathionine β-synthase (CBS) in the pathway of cysteine catabolism. We hypothesized that, by disrupting cysteine metabolic flux, chemoresistance would be reverted. Since the xCT transporter is also able to take up selenium, we used selenium-containing chrysin (SeChry) as a plausible competitive inhibitor of xCT. For that, we tested the effects of SeChry on three different ovarian cancer cell lines (ES2, OVCAR3, and OVCAR8) and in two non-malignant cell lines (HaCaT and HK2). Results showed that, in addition to being highly cytotoxic, SeChry does not affect the uptake of cysteine, although it increases GSH depletion, indicating that SeChry might induce oxidative stress. However, enzymatic assays revealed an inhibitory effect of SeChry toward CBS, thus preventing production of the antioxidant H2S. Notably, our data showed that SeChry and folate-targeted polyurea dendrimer generation four (SeChry@PUREG4-FA) nanoparticles increased the specificity for SeChry delivery to ovarian cancer cells, reducing significantly the toxicity against non-malignant cells. Collectively, our data support SeChry@PUREG4-FA nanoparticles as a targeted strategy to improve ovarian cancer treatment, where GSH depletion and CBS inhibition underlie SeChry cytotoxicity.publishersversionpublishe

Gain- and Loss-of-Function CFTR Alleles Are Associated with COVID-19 Clinical Outcomes

Carriers of single pathogenic variants of the CFTR (cystic fibrosis transmembrane conductance regulator) gene have a higher risk of severe COVID-19 and 14-day death. The machine learning post-Mendelian model pinpointed CFTR as a bidirectional modulator of COVID-19 outcomes. Here, we demonstrate that the rare complex allele [G576V;R668C] is associated with a milder disease via a gain-of-function mechanism. Conversely, CFTR ultra-rare alleles with reduced function are associated with disease severity either alone (dominant disorder) or with another hypomorphic allele in the second chromosome (recessive disorder) with a global residual CFTR activity between 50 to 91%. Furthermore, we characterized novel CFTR complex alleles, including [A238V;F508del], [R74W;D1270N;V201M], [I1027T;F508del], [I506V;D1168G], and simple alleles, including R347C, F1052V, Y625N, I328V, K68E, A309D, A252T, G542*, V562I, R1066H, I506V, I807M, which lead to a reduced CFTR function and thus, to more severe COVID-19. In conclusion, CFTR genetic analysis is an important tool in identifying patients at risk of severe COVID-19

A genome-wide association study for survival from a multi-centre European study identified variants associated with COVID-19 risk of death

: The clinical manifestations of SARS-CoV-2 infection vary widely among patients, from asymptomatic to life-threatening. Host genetics is one of the factors that contributes to this variability as previously reported by the COVID-19 Host Genetics Initiative (HGI), which identified sixteen loci associated with COVID-19 severity. Herein, we investigated the genetic determinants of COVID-19 mortality, by performing a case-only genome-wide survival analysis, 60 days after infection, of 3904 COVID-19 patients from the GEN-COVID and other European series (EGAS00001005304 study of the COVID-19 HGI). Using imputed genotype data, we carried out a survival analysis using the Cox model adjusted for age, age2, sex, series, time of infection, and the first ten principal components. We observed a genome-wide significant (P-value < 5.0 × 10-8) association of the rs117011822 variant, on chromosome 11, of rs7208524 on chromosome 17, approaching the genome-wide threshold (P-value = 5.19 × 10-8). A total of 113 variants were associated with survival at P-value < 1.0 × 10-5 and most of them regulated the expression of genes involved in immune response (e.g., CD300 and KLR genes), or in lung repair and function (e.g., FGF19 and CDH13). Overall, our results suggest that germline variants may modulate COVID-19 risk of death, possibly through the regulation of gene expression in immune response and lung function pathways

Host genetics and COVID-19 severity: increasing the accuracy of latest severity scores by Boolean quantum features

The impact of common and rare variants in COVID-19 host genetics has been widely studied. In particular, in Fallerini et al. (Human genetics, 2022, 141, 147–173), common and rare variants were used to define an interpretable machine learning model for predicting COVID-19 severity. First, variants were converted into sets of Boolean features, depending on the absence or the presence of variants in each gene. An ensemble of LASSO logistic regression models was used to identify the most informative Boolean features with respect to the genetic bases of severity. After that, the Boolean features, selected by these logistic models, were combined into an Integrated PolyGenic Score (IPGS), which offers a very simple description of the contribution of host genetics in COVID-19 severity.. IPGS leads to an accuracy of 55%–60% on different cohorts, and, after a logistic regression with both IPGS and age as inputs, it leads to an accuracy of 75%. The goal of this paper is to improve the previous results, using not only the most informative Boolean features with respect to the genetic bases of severity but also the information on host organs involved in the disease. In this study, we generalize the IPGS adding a statistical weight for each organ, through the transformation of Boolean features into “Boolean quantum features,” inspired by quantum mechanics. The organ coefficients were set via the application of the genetic algorithm PyGAD, and, after that, we defined two new integrated polygenic scores (IPGSph1 and IPGSph2). By applying a logistic regression with both IPGS, (IPGSph2 (or indifferently IPGSph1) and age as inputs, we reached an accuracy of 84%–86%, thus improving the results previously shown in Fallerini et al. (Human genetics, 2022, 141, 147–173) by a factor of 10%

Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

xCT (SLC7A11)- Antiporter system role in ovarian cancer chemoresistance.

Ovarian cancer is the main cause of death among gynaecologic diseases and the most wide-spread malignancy in women over 40 years of age after breast cancer. The causes of that situa-tion are substantially three: the histological and molecular heterogeneity; the late diagnosis and detection and finally chemoresistance. Epithelial ovarian cancer, called carcinomas, is the most common (85-90%) and comprehend two different histotypes based on their type of chemoresistance: ovarian serous carcinoma (OSC) characterized by an acquired chemo-resistance and ovarian clear cell carcinoma (OCCC) that shows an intrinsic form of chemo-resistance. Considering that chemoresistance is the reduction of the efficiency of chemotherapy and that glutathione (GSH) is able to nick platinum-based drug effectiveness, the main role of GSH and cysteine (rate-limiting substrate for GSH synthesis), in ovarian cancer, was hypothe-sized. Since the main role of xCT/SLC7A11 in cyst(e)ine transport, we decided to investigate the role of that protein in ovarian cancer chemoresistance using three ovarian cancer cell lines (ES2, OVCAR3 and OVCAR8), upon exposure to cysteine and cisplatin. Therefore, sustaining the idea that NF E2 Relator Factor 2 (NRF2) was able to regulate the xCT/SLC7A11 transcription (in stressful conditions) by binding ARE enhancer sequence in xCT/SLC7A11 promoter, the cells were exposed to Selenium-containing Chrysin (SeChry) that was reported to largely impact xCT expression. Our results, confirmed the role of cysteine in the protection against the damages caused by platinum drugs and the role of xCT in the transport of cysteine, enhancing chemo-resistance. Concerning SeChry impacts NRF2 binding xCT/SLC7A11 promoter, the results preliminarily showed that NRF2 has a role in xCT/SLC7A11 expression in OVCAR3 cells exposed to SeChry. The results of that thesis have contributed to publish an article on Nutrients: “Targeting Gluta-thione and Cystathione β-Synthase in Ovarian Cancer Treatment by Selenium-Chrysin Polyurea Dendrimer Nanoformulation”

Long-term follow-up after endoscopic forceps biopsies for early stage duodenal carcinoid: case report and review of endoscopic treatments

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Long-Term oncologic results and complications after preoperative chemoradiotherapy for rectal cancer: a Single-Institution experience after a median Follow-Up of 95 months.

Background This study sought to evaluate the long-term outcome and complications, and occurrence of second malignancy after preoperative chemoradiotherapy (pCRT) for rectal cancer. Methods One hundred twenty-three consecutive patients (78 men, 45 women) with locally advanced mid-low rectal cancer underwent pCRT between 1994 and 2002. Patients were followed up by one surgeon with a standard protocol, and data were prospectively recorded in a dedicated database. No patient was lost to follow-up. Complications were defined as late if they occurred >6 months after surgery. Overall and disease-free survival were calculated by the Kaplan-Meier method. Results Of 123 patients, 111 underwent an R0 procedure. The rate of pathologic complete response was 16% (n = 20 patients). At a median follow-up of 95 (range, 56–160) months, 50 late complications occurred in 41 patients, 21 of whom required surgery. In seven cases, the complications were clearly CRT related and were significantly associated with the total dose of radiation delivered (P < .05). The estimated 5- and 10-year overall survival was 76% and 67%, respectively. The estimated 5- and 10-year disease-free survival was 83% and 82%, respectively. In 18 of 19 patients who experienced recurrence (local, n = 3; distant, n = 16), it occurred within 48 months from surgery. The most frequent site of metastasis as first site of recurrence was the lung (9 of 19). The most frequent second primary malignancy was lung cancer (3 of 8). Conclusions Despite satisfactory oncological outcome, late morbidity after pCRT is relevant and related to the radiotherapy dose used. Most recurrences and second malignancies were located in the lung