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Pharmacological Research Jun 2024Adagrasib (MRTX849), an approved and promising KRAS G12C inhibitor, has shown the promising results for treating patients with advanced non-small cell lung cancer...
Adagrasib (MRTX849), an approved and promising KRAS G12C inhibitor, has shown the promising results for treating patients with advanced non-small cell lung cancer (NSCLC) or colorectal cancer (CRC) harboring KRAS-activating mutations. However, emergence of the acquired resistance limits its long-term efficacy and clinical application. Further understanding of the mechanism of the acquired resistance is crucial for developing more new effective therapeutic strategies. Herein, we firstly found a new connection between the acquired resistance to MRTX849 and nuclear factor erythroid 2-related factor 2 (Nrf2). The expression levels of Nrf2 and GLS1 proteins were substantially elevated in different CRC cell lines with the acquired resistance to MRTX849 in comparison with their corresponding parental cell lines. Next, we discovered that RA-V, one of natural cyclopeptides isolated from the roots of Rubia yunnanensis, could restore the response of resistant CRC cells to MRTX849. The results of molecular mechanisms showed that RA-V suppressed Nrf2 protein through the ubiquitin-proteasome-dependent degradation, leading to the induction of oxidative and ER stress, and DNA damage in CRC cell lines. Consequently, RA-V reverses the resistance to MRTX849 by inhibiting the Nrf2/GLS1 axis, which shows the potential for further developing into one of novel adjuvant therapies of MRTX849.
PubMed: 38945380
DOI: 10.1016/j.phrs.2024.107252 -
Toxicology in Vitro : An International... Jun 2024Hepatocellular carcinoma (HCC) is a significant contributor to cancer-related deaths globally. Systemic therapy is the only treatment option for HCC at an advanced...
Hepatocellular carcinoma (HCC) is a significant contributor to cancer-related deaths globally. Systemic therapy is the only treatment option for HCC at an advanced stage, with limited therapeutic response. In this study, we evaluated the antitumor potential of four N-acylhydrazone (NAH) derivatives, namely LASSBio-1909, 1911, 1935, and 1936, on HCC cell lines. We have previously demonstrated that the aforementioned NAH derivatives selectively inhibit histone deacetylase 6 (HDAC6) in lung cancer cells, but their effects on HCC cells have not been explored. Thus, the present study aimed to evaluate the effects of NAH derivatives on the proliferative behavior of HCC cells. LASSBio-1911 was the most cytotoxic compound against HCC cells, however its effects were minimal on normal cells. Our results showed that LASSBio-1911 inhibited HDAC6 in HCC cells leading to cell cycle arrest and decreased cell proliferation. There was also an increase in the frequency of cells in mitosis onset, which was associated with disturbing mitotic spindle formation. These events were accompanied by elevated levels of CDKN1A mRNA, accumulation of CCNB1 protein, and sustained ERK1 phosphorylation. Furthermore, LASSBio-1911 induced DNA damage, resulting in senescence and/or apoptosis. Our findings indicate that selective inhibition of HDAC6 may provide an effective therapeutic strategy for the treatment of advanced HCC, including tumor subtypes with integrated viral genome. Further, in vivo studies are required to validate the antitumor effect of LASSBio-1911 on liver cancer.
PubMed: 38945376
DOI: 10.1016/j.tiv.2024.105884 -
Lung Cancer (Amsterdam, Netherlands) Jun 2024Pathogenic or likely pathogenic germline variants (PGVs) in cancer predisposition genes may play a role in lung cancer (LC) susceptibility. However, determining an...
INTRODUCTION
Pathogenic or likely pathogenic germline variants (PGVs) in cancer predisposition genes may play a role in lung cancer (LC) susceptibility. However, determining an eligible population for genetic testing remains uncertain. This study aimed to assess the prevalence of PGVs in a selected cohort of individuals with lung adenocarcinoma.
METHODS
A cross-sectional cohort study was conducted to assess the PGVs rate in lung adenocarcinoma patients with a family history of LC, young-onset presentation, history of never/light smoking, or actionable genomic alterations (AGAs). Sequencing was performed using Sophia Hereditary Cancer Solution panel F, including 144 cancer predisposition genes. Variants classified as pathogenic or likely pathogenic were included for further analysis.
RESULTS
Of 201 patients, 43 (21.4 %) exhibited PGVs, among which 64.5 % were DNA damage repair genes, and 86.1 % were clinically actionable. The main PGVs were in ATM (9.3 %), TP53 (6.9 %), BRCA2 (6.9 %), and CHEK2 (6.9 %) genes. PGVs were associated with male sex (adjusted odds ratio [aOR] 2.46, 95 % CI 1.15-5.32, p = 0.021), along with a trend toward association with AGAs (aOR 6.04, 95 % CI 0.77-49.74, p = 0.094).
CONCLUSIONS
In this study, a high PGVs prevalence was identified based on our selection criteria, which represents an effective strategy to identify candidates for germline genomic testing, potential screening strategies in close relatives, and personalized therapeutic modalities. Our results warrant further exploration in other populations to confirm them.
PubMed: 38945003
DOI: 10.1016/j.lungcan.2024.107864 -
Mutation Research Jun 2024Reactive aldehydes, for instance, formaldehyde and acetaldehyde, are important endogenous or environmental mutagens by virtue of their abilities to produce a DNA lesion... (Review)
Review
Reactive aldehydes, for instance, formaldehyde and acetaldehyde, are important endogenous or environmental mutagens by virtue of their abilities to produce a DNA lesion called interstrand crosslink (ICL). Aldehyde-metabolizing enzymes such as aldehyde dehydrogenases (ALDHs) and the Fanconi anemia (FA) pathway constitute the main defense lines against aldehyde-induced genotoxicity. Biallelic mutations of genes in any one of the FA complementation groups can impair the ICL repair mechanism and cause FA, a heterogeneous disorder manifested by bone marrow failure (BMF), congenital abnormality and a strong predisposition to cancer. The defective ALDH2 polymorphism rs671 (ALDH2*2) is a known risk and prognostic factor for alcohol drinking-associated cancers. Recent studies suggest that it also promotes BMF and cancer development in FA, and its combination with alcohol dehydrogenase 5 (ADH5) mutations causes aldehyde degradation deficiency syndrome (ADDS), also known by its symptoms as aplastic anemia, mental retardation, and dwarfism syndrome. ALDH2*2 and another pathogenic variant in the alcohol-metabolizing pathway, ADH1B1*1, is prevalent among East Asians. Also, other ALDH2 genotypes with disease-modifying potentials have lately been identified in different populations. Therefore, it would be appropriate to summarize current knowledge of genotoxic aldehydes and defense mechanisms against them to shed new light on the pathogenic effects of ALDH2 variants together with other genetic and environmental modifiers on cancer and inherited BMF syndromes. Lastly, we also presented potential treatment strategies for FA, ADDS and cancer based on the manipulation of aldehyde-induced genotoxicity.
PubMed: 38944932
DOI: 10.1016/j.mrfmmm.2024.111870 -
Food Chemistry Jun 2024Tea is widely consumed in both beverages and food. Epigallocatechin gallate (EGCG) is the most crucial active ingredient in tea. Currently, knowledges on transformation...
Tea is widely consumed in both beverages and food. Epigallocatechin gallate (EGCG) is the most crucial active ingredient in tea. Currently, knowledges on transformation processes of EGCG during tea processing are lacking. Understanding the chemical reactions of EGCG and its products during tea processing is important for assessing the safety of tea-containing food. Here, we revealed the formation of persistent free radicals (PFRs) from EGCG under the influence of heating and light irradiation, which was substantiated with evidence. These PFRs exhibited stability for >30 min in simulated gastric fluid. Furthermore, we observed potential effects of these PFRs on DNA damage and cell cytotoxicity in vitro. By combining electron paramagnetic resonance spectrometer with Fourier transform ion cyclotron resonance mass spectrometry, we elucidated the pathways involved in free radical formation. These findings are expected to contribute to a comprehensive understanding of free radical chemistry in tea-containing food.
PubMed: 38944926
DOI: 10.1016/j.foodchem.2024.140241 -
Mymensingh Medical Journal : MMJ Jul 2024Parkinson's disease (PD) is a chronic, progressive neurodegenerative disease with unknown etiology. Some previous studies suggest that elevated serum homocysteine level...
Parkinson's disease (PD) is a chronic, progressive neurodegenerative disease with unknown etiology. Some previous studies suggest that elevated serum homocysteine level is a risk factor for stroke, ischemic heart disease; atherosclerosis and neurodegenerative diseases like Parkinson's disease. Serum homocysteine level relates with Parkinson's disease through various mechanisms including gene defect, apoptosis, oxidative stress and DNA damage. Some recent studies reveal that serum homocysteine level is elevated in Parkinson's disease patient compared to healthy individuals. This study was aimed to compare the serum homocysteine level in Parkinson's disease patients and age and sex matched apparently healthy individuals. This was a case control study which was conducted in Department of Neurology and Medicine, Mymensingh Medical College Hospital, Mymensingh during November 2019 to April 2021. Total 55 cases of Parkinson's disease patients and age and sex matched 55 apparently healthy controls were enrolled in this study. Demographics and clinical data were collected using structured case record form and adopting purposive type of sampling method. Serum homocysteine level was measured in both case and control groups. The study reveals that, average age of the patients and control group was in sixth decade. Male predominance was found with male to female ratio was 1.5:1 in case group. Both groups showed almost similar demographic profiles. Twenty-nine (52.72%) patients of Parkinson's disease observed higher serum homocysteine level in contrast to only 8(14.54%) in control group. The mean serum homocysteine ±SD was 15.43±6.04μmol/L in case group and 10.04±5.31μmol/L in control group; the difference was statistically significant (p=0.001). Mean serum homocysteine levels were measured progressively higher with increased duration and advanced stages of disease. It was concluded that, serum homocysteine level is higher in Parkinson's disease patients than normal healthy individuals. In addition, there was significant positive correlation of elevated serum homocysteine with increased duration of Parkinson's disease and advanced stages of the disease.
Topics: Humans; Homocysteine; Parkinson Disease; Male; Female; Case-Control Studies; Middle Aged; Aged; Adult; Risk Factors
PubMed: 38944701
DOI: No ID Found -
Cancer Genomics & Proteomics 2024BRCA1/2 mutations in breast cancer cells impair homologous recombination and promote alternative end joining (Alt-EJ) for DNA-damage repair. DNA polymerase theta,...
BACKGROUND/AIM
BRCA1/2 mutations in breast cancer cells impair homologous recombination and promote alternative end joining (Alt-EJ) for DNA-damage repair. DNA polymerase theta, encoded by POLQ, plays a crucial role in Alt-EJ, making it a potential therapeutic target, particularly in BRCA1/2-mutant cancers. Methionine restriction is a promising approach to target cancer cells due to their addiction to this amino acid. The present study investigated the expression of POLQ in BRCA1/2 wild-type and BRCA1-mutant breast cancer cells under methionine restriction.
MATERIALS AND METHODS
POLQ mRNA expression was measured using qRT-PCR in BRCA1/2 wild-type (MDA-MB-231) and BRCA1- mutant (HCC1937 and MDA-MB-436) breast-cancer cells under normal, or serum-restricted, or serum- and methionine-restricted conditions.
RESULTS
Compared to BRCA1/2 wild-type cells, BRCA1-mutant cells displayed significantly higher basal POLQ expression in normal medium. Methionine restriction further increased POLQ expression in the BRCA1-mutant cells but decreased it in the BRCA1/2 wild-type cells.
CONCLUSION
The present findings suggest that methionine restriction showed differential effects on POLQ expression, potentially impacting Alt-EJ activity, in BRCA1/2 wild-type and BRCA1-mutant breast-cancer cells. Further investigation is needed to explore the potential of combining methionine restriction with DNA-repair inhibitors, such as PARP inhibitors, to overcome drug resistance in BRCA1/2 mutant cancers.
Topics: Humans; Methionine; Breast Neoplasms; Female; BRCA1 Protein; Mutation; DNA Polymerase theta; DNA-Directed DNA Polymerase; DNA Repair; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; BRCA2 Protein
PubMed: 38944428
DOI: 10.21873/cgp.20458 -
Chemico-biological Interactions Jun 2024Cadmium (Cd) is a widely used heavy metal and has recently been recognized as a possible source of human toxicity due to its ability to accumulate in organs....
Cadmium (Cd) is a widely used heavy metal and has recently been recognized as a possible source of human toxicity due to its ability to accumulate in organs. Accumulation of heavy metals has several adverse effects, including inducing inflammation, in multiple organs, such as the testis. However, how Cd ions are sensed by host cells and how tissue inflammation eventually occurs remains unclear. Here, we show that Cd activates the AIM2 inflammasome by mediating genomic DNA release into the cytoplasm after DNA damage via oxidative stress, to trigger IL-1β secretion and pyroptosis. Specifically, the toxicity effects induced by Cd in cells were prevented by melatonin, which served as an antagonist of oxidative stress. Accordingly, in a mouse model, Cd-induced inflammation in the testis and consequential male reproductive dysfunction were effectively reversed by melatonin. Thus, our results suggest a function of AIM2 in Cd-mediated testis inflammation and identify AIM2 as a major pattern recognition receptor in response to heavy metal Cd ions.
PubMed: 38944328
DOI: 10.1016/j.cbi.2024.111122 -
The Science of the Total Environment Jun 2024Trichloroethylene (TCE) is a common environmental pollutant and industrial chemical that has been associated with adverse health effects, especially on organ systems.... (Review)
Review
Trichloroethylene (TCE) is a common environmental pollutant and industrial chemical that has been associated with adverse health effects, especially on organ systems. The purpose of this review is to summarize the current findings on organ system damage caused by TCE exposure and the underlying mechanisms involved. Numerous studies have shown that TCE exposure may cause damage to multiple organ systems, mainly the skin, liver, kidney, and circulatory system. The mechanisms leading to TCE-induced organ system damage are complex and diverse. TCE is metabolized in vivo to reactive intermediates, through which TCE can induce oxidative stress, interfere with cell signaling pathways, and promote inflammatory responses. In addition, studies have shown that TCE interferes with DNA repair mechanisms, leading to genotoxicity and potentially carcinogenic effects. This review highlights the importance of understanding the deleterious effects of TCE exposure on organ systems and provides insights into the underlying mechanisms involved. Further research is needed to elucidate the full range of organ system damage caused by TCE and to develop effective prevention and treatment strategies.
PubMed: 38944297
DOI: 10.1016/j.scitotenv.2024.174029 -
Pathology, Research and Practice Jun 2024Usual Interstitial Pneumonia (UIP) a fibrosing pneumonia is associated with idiopathic pulmonary fibrosis, chronic autoimmune disease (AID), or hypersensitivity...
BACKGROUND
Usual Interstitial Pneumonia (UIP) a fibrosing pneumonia is associated with idiopathic pulmonary fibrosis, chronic autoimmune disease (AID), or hypersensitivity pneumonia. Oxygen radicals, due to tobacco smoke, can damage DNA and might upregulate PARP1. Cytosolic DNA from dying pneumocytes activate cytosolic GMP-AMP-synthase-stimulator of interferon genes (cGAS-STING) pathway and TREX1. Prolonged inflammation induces senescence, which might be inhibited by phagocytosis, eliminating nuclear debris. We aimed to evaluate activation of cGAS-STING-TREX1 pathway in UIP, and if phagocytosis and anti-phagocytosis might counteract inflammation.
METHODS
44 cases of UIP with IPF or AID were studied for the expression of cGAS, pSTING, TREX1 and PARP1. LAMP1 and Rab7 expression served as phagocytosis markers. CD47 protecting phagocytosis and p16 to identify senescent cells were also studied.
RESULTS
Epithelial cells in remodeled areas and macrophages expressed cGAS-pSTING, TREX1; epithelia but not macrophages stained for PARP1. Myofibroblasts, endothelia, and bronchial/bronchiolar epithelial cells were all negative except early myofibroblastic foci expressing cGAS. Type II pneumocytes expressed cGAS and PARP1, but less pSTING. TREX1 although expressed was not activated. Macrophages and many regenerating epithelial cells expressed LAMP1 and Rab7. CD47, the 'don't-eat-me-signal', was expressed by macrophages and epithelial cells including senescence cells within the remodeled areas.
CONCLUSIONS
The cGAS-STING pathway is activated in macrophages and epithelial cells within remodeled areas. LikelyTREX1 because not activated cannot sufficiently degrade DNA fragments. PARP1 activation points to smoking-induced oxygen radical release, prolonging inflammation and leading to fibrosis. By expressing CD47 epithelial cells within remodeled areas protect themselves from being eliminated by phagocytosis.
PubMed: 38944022
DOI: 10.1016/j.prp.2024.155432