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ACS Chemical Biology Jun 2024Currently, the CRISPR-Cas9 system serves as a prevalent tool for genome editing and gene expression regulation. Its therapeutic application is limited by off-target...
Currently, the CRISPR-Cas9 system serves as a prevalent tool for genome editing and gene expression regulation. Its therapeutic application is limited by off-target effects that can affect genomic integrity through nonspecific, undesirable changes in the genome. Various strategies have been explored to mitigate the off-target effects. Many approaches focus on modifying components of the system, namely, Cas9 and guide RNAs, to enhance specificity. However, a common challenge is that methods aiming to increase specificity often result in a significant reduction in the editing efficiency. Here, we introduce a novel approach to modifying crRNA to balance CRISPR-Cas9 specificity and efficiency. Our approach involves incorporating nucleoside modifications, such as replacing ribo- to deoxyribonucleosides and backbone modifications, using phosphoryl guanidine groups, specifically 1,3-dimethylimidazolidin-2-ylidene phosphoramidate. In this case, within the first 10 nucleotides from the 5' crRNA end, phosphodiester bonds are substituted with phosphoryl guanidine groups. We demonstrate that crRNAs containing a combination of deoxyribonucleosides and single or multiple phosphoryl guanidine groups facilitate the modulation of CRISPR-Cas9 system activity while improving its specificity .
Topics: CRISPR-Cas Systems; DNA; Gene Editing; Guanidine; RNA, Guide, CRISPR-Cas Systems; RNA; Humans; Guanidines
PubMed: 38814157
DOI: 10.1021/acschembio.4c00147 -
ACS Applied Materials & Interfaces Jun 2024Gemcitabine (GEM) is a nucleoside analogue approved as a first line of therapy for pancreatic ductal adenocarcinoma (PDAC). However, rapid metabolism by plasma cytidine...
Gemcitabine (GEM) is a nucleoside analogue approved as a first line of therapy for pancreatic ductal adenocarcinoma (PDAC). However, rapid metabolism by plasma cytidine deaminase leading to the short half-life, intricate intracellular metabolism, ineffective cell uptake, and swift development of chemoresistance downgrades the clinical efficacy of GEM. ONC201 is a small molecule that inhibits the Akt and ERK pathways and upregulates the TNF-related apoptosis-inducing ligand (TRAIL), which leads to the reversal of both intrinsic and acquired GEM resistance in PDAC treatment. Moreover, the pancreatic cancer cells that were able to bypass apoptosis after treatment of ONC201 get arrested in the G1-phase, which makes them highly sensitive to GEM. To enhance the in vivo stability of GEM, we first synthesized a disulfide bond containing stearate conjugated GEM (lipid-GEM), which makes it sensitive to the redox tumor microenvironment (TME) comprising high glutathione levels. In addition, with the help of colipids 1,2-dioleoyl-glycero-3-phosphocholine (DOPC), cholesterol, and 1,2-distearoyl-glycero-3-phosphoethanolamine-poly(ethylene glycol)-2000 (DSPE-PEG 2000), we were able to synthesize the lipid-GEM conjugate and ONC201 releasing liposomes. A cumulative drug release study confirmed that both ONC201 and GEM showed sustained release from the formulation. Since MUC1 is highly expressed in 70-90% PDAC, we conjugated a MUC1 binding peptide in the liposomes which showed higher cytotoxicity, apoptosis, and cellular internalization by MIA PaCa-2 cells. A biodistribution study further confirmed that the systemic delivery of the liposomes through the tail vein resulted in a higher accumulation of drugs in orthotopic PDAC tumors in NSG mice. The IHC of the excised tumor grafts further confirmed the higher apoptosis and lower metastasis and cell proliferation. Thus, our MUC1 targeting binary drug-releasing liposomal formulation showed higher drug payload, enhanced plasma stability, and accumulation of drugs in the pancreatic orthotopic tumor and thus is a promising therapeutic alternative for the treatment of PDAC.
Topics: Deoxycytidine; Animals; Gemcitabine; Mice; Pancreatic Neoplasms; Humans; Cell Line, Tumor; Pyrimidines; Apoptosis; Liposomes; Carcinoma, Pancreatic Ductal; Antineoplastic Agents
PubMed: 38813771
DOI: 10.1021/acsami.4c02626 -
Turkish Journal of Medical Sciences 2023Temporomandibular Disorders (TMD), as in the occurrence of many diseases, have been associated with oxidative stress (OS) resulting from the disruption of antioxidant...
BACKGROUND/AIM
Temporomandibular Disorders (TMD), as in the occurrence of many diseases, have been associated with oxidative stress (OS) resulting from the disruption of antioxidant mechanisms and the accumulation of reactive oxygen species in tissues. This study was designed to compare salivary and serum OS and inflammation markers of individuals with TMD and healthy subjects.
MATERIALS AND METHODS
A prospective cross-sectional study was conducted. Twenty-seven TMD patients diagnosed with disc displacement (DD) according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and 17 healthy subjects were enrolled in the study. Prior to any treatment, serum, and saliva samples were taken from the patients and centrifuged, and stored at -80 °C until analyzed. All samples were examined for Interleukin-6 (IL-6), Malondialdehyde (MDA), and 8-hydroxydeoxyguanosine (8-OHdG) concentrations.
RESULTS
There was no significant difference between the groups regarding median values of 8-OHdG, IL-6, and MDA (p > 0.05). When the relationship between serum and salivary 8-OHdG, IL-6, and MDA levels in all subjects was evaluated, there was a strong positive correlation between the levels of 8-OHdG and IL-6 in the serum (r = 0.752, p <0.001). In the study group, when the relationship between pain levels and serum and saliva 8-OHdG, IL-6, and MDA levels was assessed, a positive and strong correlation was found between the levels of 8-OHdG and IL-6 in serum.
CONCLUSION
Although the strong correlation between pain scores and serum 8-OHdG and MDA levels supports the hypothesis that inflammation and OS mechanisms may be interrelated, according to the results of the study, inflammatory and OS markers in patients with TMD were not different from healthy individuals.
Topics: Humans; Oxidative Stress; Saliva; Temporomandibular Joint Disorders; Female; Adult; Male; Cross-Sectional Studies; Biomarkers; Interleukin-6; Prospective Studies; Malondialdehyde; Inflammation; 8-Hydroxy-2'-Deoxyguanosine; Young Adult; Middle Aged
PubMed: 38813510
DOI: 10.55730/1300-0144.5737 -
Turkish Journal of Medical Sciences 2023Titanium dioxide nanoparticles are widely used in a variety of products, including sunscreens, paints, and ceramics. However, their increasing use has raised concerns...
BACKGROUND/AIM
Titanium dioxide nanoparticles are widely used in a variety of products, including sunscreens, paints, and ceramics. However, their increasing use has raised concerns about their potential health risks. Titanium dioxide nanoparticles have been shown to have the ability to enter the bloodstream and accumulate in various tissues, reaching the fetus via the placenta. The aim of this study was to investigate the cytotoxic effects of titanium dioxide nanoparticles on a human embryonic lung cell line (HEL 299/An1) and the formation of oxidative DNA damage.
MATERIALS AND METHODS
The cytotoxic effects of brookite-based titanium dioxide nanoparticles (<100 nm) were assessed using the 3-(4,5-dimethyldiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) assay for 24 and 48 h. Cell titanium levels were determined using inductively coupled plasma mass spectrometry. Oxidative DNA damage was assessed by measuring the levels of 8-hydroxy-2-deoxyguanosine (8-OHdG) as a biomarker.
RESULTS
Titanium dioxide nanoparticles caused dose-dependent cytotoxicity in HEL 299/An1 cells. The IC values were 25.93 μM and 0.054 μM after 24 h and 48 h of exposure, respectively. Cell titanium levels were found to be 25,967 ppb after 24 h and 210,353 ppb after 48 h (p < 0.01). 8-OHdG was detected at 32.96 ng/mL after 24 h of exposure and 17.89 ng/mL after 48 h of exposure.
CONCLUSION
In our study, it was shown that titanium nanoparticles caused dose-dependent cytotoxicity and oxidative DNA damage in human embryonic lung cells. The nanoparticles also accumulated in cells and were taken up in higher amounts after 48 h of exposure. These findings suggest that titanium dioxide nanoparticles may pose a health risk, especially for pregnant women who may not be aware of their pregnancy. Therefore, it is important to take preventive measures to reduce exposure to these nanoparticles.
Topics: Titanium; Humans; DNA Damage; Cell Line; Lung; Oxidative Stress; Nanoparticles; 8-Hydroxy-2'-Deoxyguanosine; Cell Survival; Metal Nanoparticles
PubMed: 38813501
DOI: 10.55730/1300-0144.5733 -
Turkish Journal of Medical Sciences 2023People living with human immunodeficiency virus (PLWH) are getting older. Age-related comorbidities in PLWH result in polypharmacy and increase the risk for potential...
BACKGROUND/AIM
People living with human immunodeficiency virus (PLWH) are getting older. Age-related comorbidities in PLWH result in polypharmacy and increase the risk for potential drug-drug interactions (pDDIs). This study aimed to evaluate how the rate of pDDIs would change if the treatment of patients receiving different combined antiretroviral therapies (ARTs) were theoretically changed with dolutegravir/lamivudine (DTG+3TC) or cabotegravir/rilpivirine (CAB+RPV).
MATERIALS AND METHODS
This study was conducted at the infectious disease outpatient clinic of a university hospital as a follow-up of a previous study. The data of PLWH receiving at least 1 comedication other than antiretrovirals (ARVs) were retrospectively reviewed and analyzed. The Drugs.com/Drug Interactions Checker and University of Liverpool HIV Drug Interactions Checker databases were used to identify pDDIs and their severities.
RESULTS
A total of 75 PLWH, of whom 83% were male, with a mean age (± standard deviation) of 46.5 (±12.98) years were included. Polypharmacy was observed in 59 (79%) of the participants; however, with dual ARV options, the probability of polypharmacy was 35 (47%) (p < 0.001). In the Drugs.com database, no significant difference was found in terms of pDDIs between the treatment of current ARTs (64%) and DTG/3TC (%44) (p = 0.06) or CAB/RPV (%64) (p = 0.521). However, in the University of Liverpool database, the current rate of pDDIs (55%) was significantly higher compared to the theoretical treatment of DTG/3TC (40%) (p = 0.029), oral CAB/RPV (48%) (p = 0.003), and injectable CAB/RPV (31%) use (p = 0.006).
CONCLUSION
The results suggest that dual treatment regimens can reduce pDDIs, resulting in better tolerance and probably higher quality of life among PLWH.
Topics: Humans; Drug Interactions; Retrospective Studies; Male; Female; Middle Aged; HIV Infections; Adult; Polypharmacy; Anti-HIV Agents; Lamivudine; Pyridones; Drug Therapy, Combination; Heterocyclic Compounds, 3-Ring; Oxazines; Anti-Retroviral Agents; Piperazines
PubMed: 38813033
DOI: 10.55730/1300-0144.5718 -
The Journal of Dermatological Treatment Dec 2024Brivudine has been used in herpes zoster (HZ) treatment for years, but the safety and efficacy of brivudine are inconclusive. Here we perform a meta-analysis to assess... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND AND OBJECTIVE
Brivudine has been used in herpes zoster (HZ) treatment for years, but the safety and efficacy of brivudine are inconclusive. Here we perform a meta-analysis to assess the efficacy, safety, incidence of postherpetic neuralgia of brivudine.
METHODS
Data of randomized controlled Trials (RCTS) were obtained from the databases of both English (PubMed, Embase, and Cochrane Library) and Chinese (China National Knowledge Infrastructure, China Science Journal Database, and WanFang Database) literatures from inception to 12 September 2022. Meta-analyses of efficacy and safety of Brivudine for the treatment of herpes zoster for RCTS were conducted.
RESULTS
The analyses included seven RCTS (2095 patients in experimental group and 2076 patients in control group) in the treatment of HZ with brivudine. It suggested that the brivudine group was superior to the control group in terms of efficacy ( = .0002) and incidence of postherpetic neuralgia ( = .04). But the incidence of adverse reactions has no significant difference between the brivudine and the control groups ( = .22). In addition, subgroup analysis of adverse events also showed that brivudine was about the same safety as other modalities in the treatment of HZ ( > .05).
CONCLUSIONS
Brivudine is effective for HZ. However, the evidence on the safety of brivudine is insufficient.
Topics: Humans; Herpes Zoster; Neuralgia, Postherpetic; Antiviral Agents; Randomized Controlled Trials as Topic; Treatment Outcome; Incidence; Bromodeoxyuridine
PubMed: 38811010
DOI: 10.1080/09546634.2024.2355256 -
Revista Peruana de Medicina... May 2024Lamivudine is one of the most prescribed drugs in the world, and is used to treat human immunodeficiency and hepatitis B. This study aimed to evaluate the quality... (Comparative Study)
Comparative Study
Lamivudine is one of the most prescribed drugs in the world, and is used to treat human immunodeficiency and hepatitis B. This study aimed to evaluate the quality attributes and compare the dissolution profiles of two batches (A and B) of generic lamivudine 150 mg tablets with the innovator drug Epivir 150 mg tablets. We conducted an analytical, experimental, cross-sectional study, and used a spectrophotometric method at a wavelength of maximum absorption (λ) corresponding to 270 nm, to measure the percentage of dissolved drug. The study evaluated identification, content, dissolution and mass uniformity. Apparatus 2 USP (Paddle) 75 rpm, 900 mL of dissolution medium (37 ± 0.5 °C) was used in three dissolution media: pH 1.2; 4.5 and 6.8. Samples of 5 mL were obtained at 5, 10, 15, 20 and 30 min. Both batches of generic lamivudine (A and B) were found to have the same dissolution kinetic profile as the innovator drug. Both formulations met the criteria of very fast dissolving (85% dissolved in 15 min), and fast dissolving (85% dissolved in 30 min) drugs. Therefore, it was not necessary to calculate the similarity factor. We concluded that generic drugs A and B are in vitro equivalents to the innovator drug Epivir. Motivation for the study. To evaluate the quality of antiretroviral drugs used in the treatment of HIV dispensed in the HAART Program of the Ministry of Health of Peru. Main findings. Two batches of generic lamivudine drugs were found to achieve a dissolution rate greater than 85% at 15 min, being equivalent in vitro to the reference product Epivir. Implications. There is a need to apply the current regulations regarding equivalence between drugs by the regulatory authority prior to their authorization and to include dissolution profile tests as a requirement in public drug purchases, especially in national strategies (HIV, TB, etc.), in order to ensure quality products for the population.
Topics: Lamivudine; Drugs, Generic; Peru; Tablets; Solubility; Cross-Sectional Studies
PubMed: 38808847
DOI: 10.17843/rpmesp.2024.411.12821 -
BMJ (Clinical Research Ed.) May 2024To evaluate the efficacy and safety of tislelizumab added to chemotherapy as first line (primary) treatment for advanced gastric or gastro-oesophageal junction... (Randomized Controlled Trial)
Randomized Controlled Trial
Tislelizumab plus chemotherapy versus placebo plus chemotherapy as first line treatment for advanced gastric or gastro-oesophageal junction adenocarcinoma: RATIONALE-305 randomised, double blind, phase 3 trial.
OBJECTIVE
To evaluate the efficacy and safety of tislelizumab added to chemotherapy as first line (primary) treatment for advanced gastric or gastro-oesophageal junction adenocarcinoma compared with placebo plus chemotherapy.
DESIGN
Randomised, double blind, placebo controlled, phase 3 study.
SETTING
146 medical centres across Asia, Europe, and North America, between 13 December 2018 and 28 February 2023.
PARTICIPANTS
1657 patients aged ≥18 years with human epidermal growth factor receptor 2 negative locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma, regardless of programmed death-ligand 1 (PD-L1) expression status, who had not received systemic anticancer therapy for advanced disease.
INTERVENTIONS
Patients were randomly (1:1) assigned to receive either tislelizumab 200 mg or placebo intravenously every three weeks in combination with chemotherapy (investigator's choice of oxaliplatin and capecitabine, or cisplatin and 5-fluorouracil) and stratified by region, PD-L1 expression, presence or absence of peritoneal metastases, and investigator's choice of chemotherapy. Treatment continued until disease progression or unacceptable toxicity.
MAIN OUTCOME MEASURES
The primary endpoint was overall survival, both in patients with a PD-L1 tumour area positivity (TAP) score of ≥5% and in all randomised patients. Safety was assessed in all those who received at least one dose of study treatment.
RESULTS
Of 1657 patients screened between 13 December 2018 and 9 February 2021, 660 were ineligible due to not meeting the eligibility criteria, withdrawal of consent, adverse events, or other reasons. Overall, 997 were randomly assigned to receive tislelizumab plus chemotherapy (n=501) or placebo plus chemotherapy (n=496). Tislelizumab plus chemotherapy showed statistically significant improvements in overall survival versus placebo plus chemotherapy in patients with a PD-L1 TAP score of ≥5% (median 17.2 months 12.6 months; hazard ratio 0.74 (95% confidence interval 0.59 to 0.94); P=0.006 (interim analysis)) and in all randomised patients (median 15.0 months 12.9 months; hazard ratio 0.80 (0.70 to 0.92); P=0.001 (final analysis)). Grade 3 or worse treatment related adverse events were observed in 54% (268/498) of patients in the tislelizumab plus chemotherapy arm versus 50% (246/494) in the placebo plus chemotherapy arm.
CONCLUSIONS
Tislelizumab added to chemotherapy as primary treatment for advanced or metastatic gastric or gastro-oesophageal junction adenocarcinoma provided superior overall survival with a manageable safety profile versus placebo plus chemotherapy in patients with a PD-L1 TAP score of ≥5%, and in all randomised patients.
TRIAL REGISTRATION
ClinicalTrials.gov NCT03777657.
Topics: Humans; Antibodies, Monoclonal, Humanized; Male; Stomach Neoplasms; Adenocarcinoma; Female; Middle Aged; Double-Blind Method; Esophageal Neoplasms; Esophagogastric Junction; Antineoplastic Combined Chemotherapy Protocols; Aged; Adult; Cisplatin; Capecitabine; Fluorouracil
PubMed: 38806195
DOI: 10.1136/bmj-2023-078876 -
Clinical Advances in Hematology &... Jun 2024The systemic treatment options for patients with metastatic colorectal cancer have recently expanded with the US Food and Drug Administration approval of fruquintinib... (Review)
Review
The systemic treatment options for patients with metastatic colorectal cancer have recently expanded with the US Food and Drug Administration approval of fruquintinib being added to previously approved trifluridine/tipiracil with or without bevacizumab and regorafenib. These therapies are recommended for use based on the initial clinical trials that focused on their safety and efficacy in extending overall survival of patients with refractory metastatic disease, as well as later studies, including the ReDOS study that confirmed the dose-escalation strategy of regorafenib to be key in optimizing duration of therapy and preventing side effects. Although more research is needed on how to sequence third-line therapies, data from real-world studies showed that switching from regorafenib to trifluridine/tipiracil with or without bevacizumab allowed patients to have a chemotherapy-free break and led to improved survival, suggesting that there may be a benefit for using regorafenib first. Current treatment guidelines state that each therapy can be given before or after the others. Generally, sequencing considerations in the refractory setting include multiple variables such as tumor characteristics, toxicities, factors that are important to the patient, response to prior lines of therapy, and extent of disease.
Topics: Humans; Colorectal Neoplasms; Antineoplastic Combined Chemotherapy Protocols; Pyridines; Trifluridine; Neoplasm Metastasis; Patient Selection; Phenylurea Compounds; Thymine; Bevacizumab; Pyrrolidines; Drug Combinations; Uracil
PubMed: 38805297
DOI: No ID Found -
FASEB Journal : Official Publication of... May 2024Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with a notoriously dismal prognosis. As a competitive inhibitor of DNA synthesis,...
Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with a notoriously dismal prognosis. As a competitive inhibitor of DNA synthesis, gemcitabine is the cornerstone drug for treating PDAC at all stages. The therapeutic effect of gemcitabine, however, is often hindered by drug resistance, and the underlying mechanisms remain largely unknown. It is unclear whether their response to chemotherapeutics is regulated by endocrine regulators, despite the association between PDAC risk and endocrine deregulation. Here, we show that prolactin receptor (PRLR) synergizes with gemcitabine in both in vitro and in vivo treatment of PDAC. Interestingly, PRLR promotes the expression of miR-4763-3p and miR-3663-5p, two novel miRNAs whose functions are unknown. Furthermore, the analysis of transcriptome sequencing data of tumors from lactating mouse models enriches the PPP pathway, a multifunctional metabolic pathway. In addition to providing energy, the PPP pathway mainly provides a variety of raw materials for anabolism. We demonstrate that two key enzymes of the pentose phosphate pathway (PPP), G6PD and TKT, are directly targeted by miR-4763-3p and miR-3663-5p. Notably, miR-4763-3p and miR-3663-5p diminish the nucleotide synthesis of the PPP pathway, thereby increasing gemcitabine sensitivity. As a result, PRLR harnesses these two miRNAs to suppress PPP and nucleotide synthesis, subsequently elevating the gemcitabine sensitivity of PDAC cells. Also, PDAC tissues and tumors from LSL-KrasG12D/+, LSL-Trp53R172H/+, and PDX1-cre (KPC) mice exhibit downregulation of PRLR. Bisulfite sequencing of PDAC tissues revealed that PRLR downregulation is due to epigenetic methylation. In this study, we show for the first time that the endocrine receptor PRLR improves the effects of gemcitabine by boosting two new miRNAs that block the PPP pathway and nucleotide synthesis by inhibiting two essential enzymes concurrently. The PRLR-miRNAs-PPP axis may serve as a possible therapeutic target to supplement chemotherapy advantages in PDAC.
Topics: Animals; Female; Humans; Mice; Antimetabolites, Antineoplastic; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Deoxycytidine; Gemcitabine; Gene Expression Regulation, Neoplastic; Glucosephosphate Dehydrogenase; MicroRNAs; Pancreatic Neoplasms; Receptors, Prolactin; Mice, Nude
PubMed: 38805171
DOI: 10.1096/fj.202302287RR