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1.
Infect Immun ; : e0019324, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38990045

ABSTRACT

Immunoglobulin A1 (IgA1) protease is a critical virulence factor of Haemophilus influenzae that facilitates bacterial mucosal infection. This study investigates the effect of iga gene polymorphism on the enzymatic activity of H. influenzae IgA1 protease. The IgA1 protease activity was examined in the H. influenzae Rd KW20 strain and 51 isolates. Genetic variations in iga and deduced amino acid substitutions affecting IgA1 protease activity were assessed. Machine learning tools and functional complementation assays were used to analyze the effects of identified substitutions on the stability and activity of IgA1 protease, respectively. All 51 isolates exhibited similar iga expression levels. No igaB expression was detected. According to comparisons with the reference Rd KW20 strain, four substitutions in the protease domain, 26 in the nonprotease passenger domain, and two in the ß-barrel domain were associated with the change in IgA1 protease activity. No substitutions in the catalytic site of IgA1 protease were observed. Logistic regression, receiver operating characteristic curves, Venn diagrams, and protein stability analyses revealed that the substitutions Asn352Lys, Pro353Ala, Lys356Asn, Gln916Lys, and Gly917Ser, which were located in the nonactive site of the passenger domain, were associated with decreases in IgA1 protease activity and stability, whereas Asn914Lys was associated with an increase in these events. Functional complementation assays revealed that the Asn914Lys substitution increased IgA1 protease activity in the Rd KW20 strain. This study identified substitutions in the nonactive site of the passenger domain that affect both the activity and stability of H. influenzae IgA1 protease.

2.
Arch Microbiol ; 206(7): 298, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38860999

ABSTRACT

A decreased chloramphenicol susceptibility in Haemophilus influenzae is commonly caused by the activity of chloramphenicol acetyltransferases (CATs). However, the involvement of membrane proteins in chloramphenicol susceptibility in H. influenzae remains unclear. In this study, chloramphenicol susceptibility testing, whole-genome sequencing, and analyses of membrane-related genes were performed in 51 H. influenzae isolates. Functional complementation assays and structure-based protein analyses were conducted to assess the effect of proteins with sequence substitutions on the minimum inhibitory concentration (MIC) of chloramphenicol in CAT-negative H. influenzae isolates. Six isolates were resistant to chloramphenicol and positive for type A-2 CATs. Of these isolates, A3256 had a similar level of CAT activity but a higher chloramphenicol MIC relative to the other resistant isolates; it also had 163 specific variations in 58 membrane genes. Regarding the CAT-negative isolates, logistic regression and receiver operator characteristic curve analyses revealed that 48T > G (Asn16Lys), 85 C > T (Leu29Phe), and 88 C > A (Leu30Ile) in HI_0898 (emrA), and 86T > G (Phe29Cys) and 141T > A (Ser47Arg) in HI_1177 (artM) were associated with enhanced chloramphenicol susceptibility, whereas 997G > A (Val333Ile) in HI_1612 (hmrM) was associated with reduced chloramphenicol susceptibility. Furthermore, the chloramphenicol MIC was lower in the CAT-negative isolates with EmrA-Leu29Phe/Leu30Ile or ArtM-Ser47Arg substitution and higher in those with HmrM-Val333Ile substitution, relative to their counterparts. The Val333Ile substitution was associated with enhanced HmrM protein stability and flexibility and increased chloramphenicol MICs in CAT-negative H. influenzae isolates. In conclusion, the substitution in H. influenzae multidrug efflux pump HmrM associated with reduced chloramphenicol susceptibility was characterised.


Subject(s)
Amino Acid Substitution , Anti-Bacterial Agents , Bacterial Proteins , Chloramphenicol O-Acetyltransferase , Chloramphenicol , Haemophilus influenzae , Microbial Sensitivity Tests , Chloramphenicol/pharmacology , Haemophilus influenzae/genetics , Haemophilus influenzae/drug effects , Haemophilus influenzae/metabolism , Haemophilus influenzae/isolation & purification , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Chloramphenicol O-Acetyltransferase/genetics , Chloramphenicol O-Acetyltransferase/metabolism , Drug Resistance, Multiple, Bacterial/genetics , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Chloramphenicol Resistance/genetics , Humans , Haemophilus Infections/microbiology , Whole Genome Sequencing
3.
Anticancer Res ; 44(4): 1353-1364, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38538001

ABSTRACT

Ataxia-telangiectasia mutated (ATM) is a pivotal protein with versatile kinase activity that responds to DNA damage. While its well-established role as a DNA repair protein is widely recognized, the understanding of its noncanonical functions in ovarian cancer remains limited. Numerous studies have investigated the potential of targeting ATM for ovarian cancer treatment. In addition to its involvement in homologous recombination repair (HRR), an increasing body of research suggests that ATM plays a role in cellular metabolism and adaptive immunity. This review focuses on the current evidence and provides a perspective on how targeting ATM in ovarian cancer can address HRR-deficient genotypes, influence macropinocytosis, and enhance immune checkpoint blockade (ICB) therapy. It underscores the diverse avenues through which targeting ATM is a potential tailored treatment for ovarian cancer.


Subject(s)
Ataxia Telangiectasia Mutated Proteins , Ovarian Neoplasms , Female , Humans , Adaptive Immunity , Ataxia Telangiectasia Mutated Proteins/genetics , Ataxia Telangiectasia Mutated Proteins/metabolism , Cell Cycle Proteins/metabolism , DNA Damage , DNA Repair , DNA-Binding Proteins/genetics , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/genetics , Protein Serine-Threonine Kinases/metabolism , Tumor Suppressor Proteins/metabolism
4.
J Acute Med ; 14(1): 39-41, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38487754

ABSTRACT

Ocular globe injury is a severe ophthalmic emergency that requires immediate attention in the emergency department. In this case report, we present a 35-year-old male who suffered a penetrating ocular injury and globe rupture caused by a nail puncture. The patient presented with severe pain and visual loss and was treated with tetanus vaccination, empirical antibiotics, and pain control, followed by an urgent orbital computed tomography (CT) scan and consultation with an ophthalmologist. The CT scan revealed a retained nail in the ocular space, and an urgent operation was performed to repair the eyeball rupture, remove the intraocular foreign body, and perform an anterior vitrectomy. The patient was discharged 6 days after the operation with a visual acuity of 20/400 and an ocular trauma score of 34. This case highlights the importance of initial emergency physician decision-making and the need for a thorough history-taking and examination when encountering penetrating ocular injuries.

6.
Molecules ; 28(8)2023 Apr 11.
Article in English | MEDLINE | ID: mdl-37110602

ABSTRACT

Genetically modified plants and crops can contribute to remarkable increase in global food supply, with improved yield and resistance to plant diseases or insect pests. The development of biotechnology introducing exogenous nucleic acids in transgenic plants is important for plant health management. Different genetic engineering methods for DNA delivery, such as biolistic methods, Agrobacterium tumefaciens-mediated transformation, and other physicochemical methods have been developed to improve translocation across the plasma membrane and cell wall in plants. Recently, the peptide-based gene delivery system, mediated by cell-penetrating peptides (CPPs), has been regarded as a promising non-viral tool for efficient and stable gene transfection into both animal and plant cells. CPPs are short peptides with diverse sequences and functionalities, capable of agitating plasma membrane and entering cells. Here, we highlight recent research and ideas on diverse types of CPPs, which have been applied in DNA delivery in plants. Various basic, amphipathic, cyclic, and branched CPPs were designed, and modifications of functional groups were performed to enhance DNA interaction and stabilization in transgenesis. CPPs were able to carry cargoes in either a covalent or noncovalent manner and to internalize CPP/cargo complexes into cells by either direct membrane translocation or endocytosis. Importantly, subcellular targets of CPP-mediated nucleic acid delivery were reviewed. CPPs offer transfection strategies and influence transgene expression at subcellular localizations, such as in plastids, mitochondria, and the nucleus. In summary, the technology of CPP-mediated gene delivery provides a potent and useful tool to genetically modified plants and crops of the future.


Subject(s)
Cell-Penetrating Peptides , Nucleic Acids , Animals , Plants, Genetically Modified/genetics , Plants, Genetically Modified/metabolism , Cell-Penetrating Peptides/chemistry , Transfection , Gene Transfer Techniques , DNA , Nucleic Acids/metabolism
7.
Antioxidants (Basel) ; 12(4)2023 Apr 08.
Article in English | MEDLINE | ID: mdl-37107275

ABSTRACT

Karyomegalic interstitial nephritis (KIN) is a genetic adult-onset chronic kidney disease (CKD) characterized by genomic instability and mitotic abnormalities in the tubular epithelial cells. KIN is caused by recessive mutations in the FAN1 DNA repair enzyme. However, the endogenous source of DNA damage in FAN1/KIN kidneys has not been identified. Here we show, using FAN1-deficient human renal tubular epithelial cells (hRTECs) and FAN1-null mice as a model of KIN, that FAN1 kidney pathophysiology is triggered by hypersensitivity to endogenous reactive oxygen species (ROS), which cause chronic oxidative and double-strand DNA damage in the kidney tubular epithelial cells, accompanied by an intrinsic failure to repair DNA damage. Furthermore, persistent oxidative stress in FAN1-deficient RTECs and FAN1 kidneys caused mitochondrial deficiencies in oxidative phosphorylation and fatty acid oxidation. The administration of subclinical, low-dose cisplatin increased oxidative stress and aggravated mitochondrial dysfunction in FAN1-deficient kidneys, thereby exacerbating KIN pathophysiology. In contrast, treatment of FAN1 mice with a mitochondria-targeted ROS scavenger, JP4-039, attenuated oxidative stress and accumulation of DNA damage, mitigated tubular injury, and preserved kidney function in cisplatin-treated FAN1-null mice, demonstrating that endogenous oxygen stress is an important source of DNA damage in FAN1-deficient kidneys and a driver of KIN pathogenesis. Our findings indicate that therapeutic modulation of kidney oxidative stress may be a promising avenue to mitigate FAN1/KIN kidney pathophysiology and disease progression in patients.

8.
J Cell Biol ; 222(1)2023 01 02.
Article in English | MEDLINE | ID: mdl-36399181

ABSTRACT

Macropinocytosis is a nonspecific endocytic process that may enhance cancer cell survival under nutrient-poor conditions. Ataxia-Telangiectasia mutated (ATM) is a tumor suppressor that has been previously shown to play a role in cellular metabolic reprogramming. We report that the suppression of ATM increases macropinocytosis to promote cancer cell survival in nutrient-poor conditions. Combined inhibition of ATM and macropinocytosis suppressed proliferation and induced cell death both in vitro and in vivo. Supplementation of ATM-inhibited cells with amino acids, branched-chain amino acids (BCAAs) in particular, abrogated macropinocytosis. Analysis of ATM-inhibited cells in vitro demonstrated increased BCAA uptake, and metabolomics of ascites and interstitial fluid from tumors indicated decreased BCAAs in the microenvironment of ATM-inhibited tumors. These data reveal a novel basis of ATM-mediated tumor suppression whereby loss of ATM stimulates protumorigenic uptake of nutrients in part via macropinocytosis to promote cancer cell survival and reveal a potential metabolic vulnerability of ATM-inhibited cells.


Subject(s)
Ataxia Telangiectasia Mutated Proteins , Neoplasms , Pinocytosis , Humans , Adaptation, Physiological , Ataxia Telangiectasia Mutated Proteins/genetics , Ataxia Telangiectasia Mutated Proteins/metabolism , Cellular Reprogramming , Neoplasms/metabolism , Tumor Microenvironment , Amino Acids, Branched-Chain/metabolism , Metabolomics , Animals , Mice , Cell Line, Tumor
9.
Int J Mol Sci ; 23(23)2022 Nov 29.
Article in English | MEDLINE | ID: mdl-36499314

ABSTRACT

Long-term exposure to arsenic may induce several human cancers, including non-melanoma skin cancer. The tissue inhibitor of metalloproteinase (TIMP)-3, encoded by the TIMP3 gene, may inhibit tumor growth, invasion, and metastasis of several cancer types. In this study, we aimed to investigate effects of the TIMP3 -1296 T > C (rs9619311) and -915 A > G (rs2234921) single-nucleotide polymorphisms (SNPs) on skin cancer risk in an arsenic-exposed population, and to evaluate the influence of allele-specific changes by an in silico analysis. In total, 1078 study participants were followed up for a median of 15 years for newly diagnosed skin cancer. New cases were identified through linkage to the National Cancer Registry of Taiwan. A Cox regression analysis was used to evaluate the effects of TIMP3 variants. Transcription factor (TF) profiling of binding sites of allele-specific changes in SNPs was conducted using the JASPAR scan tool. We observed borderline associations between TIMP3 genotypes and skin cancer risk. However, when combined with high arsenic exposure levels, the rs9619311 C allele, rs2234921 G allele, or C-G haplotype groups exhibited a greater risk of developing skin cancer compared to the respective common homozygous genotype group. The in silico analysis revealed several TF motifs located at or flanking the two SNP sites. We validated that the C allele of rs9619311 attenuated the binding affinity of BACH2, MEIS2, NFE2L2, and PBX2 to the TIMP3 promoter, and that the G allele of rs2234921 reduced the affinity of E2F8 and RUNX1 to bind to the promoter. Our findings suggest significant modifications of the effect of the association between arsenic exposure and skin cancer risk by the TIMP3 rs9619311 and rs2234921 variants. The predicted TFs and their differential binding affinities to the TIMP3 promoter provide insights into how TIMP3 interacts with arsenic through TFs in skin cancer formation.


Subject(s)
Arsenic , Skin Neoplasms , Humans , Arsenic/toxicity , Cohort Studies , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Genotype , Skin Neoplasms/chemically induced , Skin Neoplasms/genetics , Mutation , Case-Control Studies , Proto-Oncogene Proteins/genetics , Homeodomain Proteins/genetics , Tissue Inhibitor of Metalloproteinase-3/genetics
10.
Discov Oncol ; 13(1): 87, 2022 Sep 13.
Article in English | MEDLINE | ID: mdl-36098827

ABSTRACT

Cancerous inhibitor of protein phosphatase 2A (CIP2A) is an oncoprotein overexpressed in human malignancies, including prostate cancer (PCa). In this study, we aimed to explore the oncogenic function of CIP2A in PCa cells and its underlying mechanism. We showed that 63.3% (38/60 cases) of PCa tissues exhibited a high CIP2A immunostaining, compared to 25% (3/12 cases) of BPH samples (p = 0.023). Furthermore, the protein level of CIP2A was positively correlated with patients' short survival time and nuclear AR levels in PCa tissues. Compared to PZ-HPV-7, an immortalized prostate cell line, androgen-sensitive LNCaP C-33, androgen-independent LNCaP C-81, or 22Rv1 cells exhibited a high CIP2A level, associated with high protein and phosphorylation levels of AR. While AR expression and activity modulated CIP2A expression, manipulating CIP2A expression in PCa cells regulated their AR protein levels and proliferation. The reduction of CIP2A expression also enhanced the sensitivity of PCa cells toward Enzalutamide treatment. Our data further showed that depletion of polo-kinase 1 (PLK1) expression or activity in C-81 or 22Rv1 cells caused reduced protein levels of c-Myc and AR. Notably, inhibition of PLK1 activity could abolish CIP2A-promoted expressions in c-Myc, AR, and prostate-specific antigen (PSA) in C-33 cells under an androgen-deprived condition, suggesting the role of PLK1 activity in CIP2A-promoted AR expression. In summary, our data showed the existence of a novel regulation between CIP2A and AR protein levels, which is critical for promoting PCa malignancy. Thus, CIP2A could serve as a therapeutic target for PCa.

11.
Transl Oncol ; 18: 101372, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35182956

ABSTRACT

Bladder cancer is prevalent cancer worldwide with poor outcomes for patients with high-grade disease. Emerging evidence shows that alteration of metabolic status drives tumorigenesis in bladder cancer. As long noncoding RNA urothelial cancer associated 1 (UCA1) is known to play an essential role in cancer metabolisms, such as glycolysis and glutaminolysis. Chen et al. report the novel function of UCA1 in glutamine metabolism through interacting with heterogeneous nuclear ribonucleoproteins (hnRNPs) I and L (hnRNP I/L). This study reveals that UCA1 promotes glutamic pyruvate transaminase 2 (GPT2) expression at the transcription level in mechanistic studies. Inhibition of either UCA1, hnRNPI/L, or GPT2 significantly reduces bladder cancer tumor growth in the mice model. This work explores a new mechanism for glutamine metabolism and the novel therapeutic target of the UCA1-hnRNPI/L-GPT2 axis across malignancies.

13.
J Cell Mol Med ; 26(8): 2273-2284, 2022 04.
Article in English | MEDLINE | ID: mdl-35191177

ABSTRACT

Human oral squamous cell carcinoma (OSCC) is the common head and neck malignancy in the world. While surgery, radiotherapy and chemotherapy are emerging as the standard treatment for OSCC patients, the outcome is limited to the recurrence and side effects. Therefore, patients with OSCC require alternative strategies for treatment. In this study, we aimed to explore the therapeutic effect and the mode of action of the novel curcumin analog, HO-3867, against human OSCC cells. We analysed the cytotoxicity of HO-3867 using MTT assay. In vitro mechanic studies were performed to determine whether MAPK pathway is involved in HO-3867 induced cell apoptosis. As the results, we found HO-3867 suppressed OSCC cells growth effectively. The flow cytometry data indicate that HO-3867 induce the sub-G1 phase. Moreover, we found that HO-3867 induced cell apoptosis by triggering formation of activated caspase 3, caspase 8, caspase 9 and PARP. After dissecting MAPK pathway, we found HO-3867 induced cell apoptosis via the c-Jun N-terminal kinase (JNK)1/2 pathway. Our results suggest that HO-3867 is an effective anticancer agent as its induction of cell apoptosis through JNK1/2 pathway in human oral cancer cells.


Subject(s)
Carcinoma, Squamous Cell , Curcumin , Head and Neck Neoplasms , Mouth Neoplasms , Apoptosis , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Proliferation , Curcumin/therapeutic use , Humans , Mouth Neoplasms/pathology , Piperidones , Squamous Cell Carcinoma of Head and Neck
14.
Clin Transl Med ; 11(12): e627, 2021 12.
Article in English | MEDLINE | ID: mdl-34923765

ABSTRACT

Acidic nucleoplasmic DNA-binding protein 1 (And-1), an important factor for deoxyribonucleic acid (DNA) replication and repair, is overexpressed in many types of cancer but not in normal tissues. Although multiple independent studies have elucidated And-1 as a promising target gene for cancer therapy, an And-1 inhibitor has yet to be identified. Using an And-1 luciferase reporter assay to screen the Library of Pharmacologically Active Compounds (LOPAC) in a high throughput screening (HTS) platform, and then further screen the compound analog collection, we identified two potent And-1 inhibitors, bazedoxifene acetate (BZA) and an uncharacterized compound [(E)-5-(3,4-dichlorostyryl)benzo[c][1,2]oxaborol-1(3H)-ol] (CH3), which specifically inhibit And-1 by promoting its degradation. Specifically, through direct interaction with And-1 WD40 domain, CH3 interrupts the polymerization of And-1. Depolymerization of And-1 promotes its interaction with E3 ligase Cullin 4B (CUL4B), resulting in its ubiquitination and subsequent degradation. Furthermore, CH3 suppresses the growth of a broad range of cancers. Moreover, And-1 inhibitors re-sensitize platinum-resistant ovarian cancer cells to platinum drugs in vitro and in vivo. Since BZA is an FDA approved drug, we expect a clinical trial of BZA-mediated cancer therapy in the near future. Taken together, our findings suggest that targeting And-1 by its inhibitors is a potential broad-spectrum anti-cancer chemotherapy regimen.


Subject(s)
DNA-Binding Proteins/antagonists & inhibitors , Ovarian Neoplasms/drug therapy , Cell Line/drug effects , DNA-Binding Proteins/therapeutic use , Female , High-Throughput Screening Assays/methods , High-Throughput Screening Assays/statistics & numerical data , Humans , Ovarian Neoplasms/physiopathology
15.
J Am Coll Emerg Physicians Open ; 2(4): e12501, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34337596
17.
J Cell Biol ; 220(8)2021 08 02.
Article in English | MEDLINE | ID: mdl-34037658

ABSTRACT

Oncogene-induced senescence (OIS) is a stable cell cycle arrest that occurs in normal cells upon oncogene activation. Cells undergoing OIS express a wide variety of secreted factors that affect the senescent microenvironment termed the senescence-associated secretory phenotype (SASP), which is beneficial or detrimental in a context-dependent manner. OIS cells are also characterized by marked epigenetic changes. We globally assessed histone modifications of OIS cells and discovered an increase in the active histone marks H3K79me2/3. The H3K79 methyltransferase disruptor of telomeric silencing 1-like (DOT1L) was necessary and sufficient for increased H3K79me2/3 occupancy at the IL1A gene locus, but not other SASP genes, and was downstream of STING. Modulating DOT1L expression did not affect the cell cycle arrest. Together, our studies establish DOT1L as an epigenetic regulator of the SASP, whose expression is uncoupled from the senescence-associated cell cycle arrest, providing a potential strategy to inhibit the negative side effects of senescence while maintaining the beneficial inhibition of proliferation.


Subject(s)
Cellular Senescence , DNA Methylation , Epigenesis, Genetic , Fibroblasts/enzymology , Histone-Lysine N-Methyltransferase/metabolism , Histones/metabolism , Interleukin-1alpha/metabolism , 9,10-Dimethyl-1,2-benzanthracene , Animals , CCAAT-Enhancer-Binding Protein-beta/genetics , CCAAT-Enhancer-Binding Protein-beta/metabolism , Cell Cycle Checkpoints , Cell Proliferation , Female , HEK293 Cells , Histone-Lysine N-Methyltransferase/genetics , Histones/genetics , Humans , Interleukin-1alpha/genetics , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Microscopy, Fluorescence , Papilloma/chemically induced , Papilloma/genetics , Papilloma/metabolism , Papilloma/pathology , Phenotype , Secretory Pathway , Skin Neoplasms/chemically induced , Skin Neoplasms/genetics , Skin Neoplasms/metabolism , Skin Neoplasms/pathology , Tetradecanoylphorbol Acetate
18.
J Emerg Med ; 60(2): e33-e37, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33097353

ABSTRACT

BACKGROUND: Electrical injuries are common in daily life. The severity of electrical injury depends on the electric current, and assessing electrical damage is difficult because there appears to be no correlation between skin burns and visceral injury. We report a case of bilateral lung injury with pulmonary hemorrhage after exposure to low-voltage electricity. CASE REPORT: A 23-year-old man was shocked by a low-voltage (110 V) electric current while at work. He had temporary loss of consciousness and twitching in the extremities, but soon regained consciousness and spontaneously stopped twitching. Electrical burn wounds were discovered on his back and forehead. Dyspnea and hemoptysis were noted. A computed tomography scan of the chest revealed patchy infiltration and consolidation of both lungs. The patient received treatment of tranexamic acid and prophylactic antibiotics for electricity-induced lung injury and pulmonary hemorrhage. Resolution of chest radiograph abnormalities was recorded on day 7. The mild dyspnea ceased approximately 2 weeks later. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Electricity-induced lung injury should be considered in patients with electrical injury through a suspicious electrical current transmission pathway, respiratory symptoms, and corresponding imaging findings. Pulmonary complications can be serious and require early intervention.


Subject(s)
Burns, Electric , Burns , Lung Diseases , Adult , Burns, Electric/complications , Electricity , Humans , Lung/diagnostic imaging , Male , Young Adult
19.
Heliyon ; 6(9): e05097, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33024871

ABSTRACT

While therapies targeting deficiencies in the homologous recombination (HR) pathway are emerging as the standard treatment for high grade serous ovarian cancer (HGSOC) patients, this strategy is limited to the ~50% of patients with a deficiency in this pathway. Therefore, patients with HR-proficient tumors are likely to be resistant to these therapies and require alternative strategies. We found that the HR gene Ataxia Telangiectasia Mutated (ATM) is wildtype and its activity is upregulated in HGSOC compared to normal fallopian tube tissue. Interestingly, multiple pathways related to metabolism are inversely correlated with ATM expression in HGSOC specimens, suggesting that combining ATM inhibition with metabolic drugs would be effective. Analysis of FDA-approved drugs from the Dependency Map demonstrated that ATM-low cells are more sensitive to fenofibrate, a PPARα agonist that affects multiple cellular metabolic pathways. Consistently, PPARα signaling is associated with ATM expression. We validated that combined inhibition of ATM and treatment with fenofibrate is synergistic in multiple HGSOC cell lines by inducing senescence. Together, our results suggest that metabolic changes induced by ATM inhibitors are a potential target for the treatment of HGSOC.

20.
Int J Mol Sci ; 21(21)2020 Oct 24.
Article in English | MEDLINE | ID: mdl-33114312

ABSTRACT

Protein phosphorylation is one of the most important post-translational modifications, and many biological processes are related to phosphorylation, such as DNA repair, transcriptional regulation and signal transduction and, therefore, abnormal regulation of phosphorylation usually causes diseases. If we can accurately predict human phosphorylation sites, this could help to solve human diseases. Therefore, we developed a kinase-specific phosphorylation prediction system, GasPhos, and proposed a new feature selection approach, called Gas, based on the ant colony system and a genetic algorithm and used performance evaluation strategies focused on different kinases to choose the best learning model. Gas uses the mean decrease Gini index (MDGI) as a heuristic value for path selection and adopts binary transformation strategies and new state transition rules. GasPhos can predict phosphorylation sites for six kinases and showed better performance than other phosphorylation prediction tools. The disease-related phosphorylated proteins that were predicted with GasPhos are also discussed. Finally, Gas can be applied to other issues that require feature selection, which could help to improve prediction performance. GasPhos is available at http://predictor.nchu.edu.tw/GasPhos.


Subject(s)
Computational Biology/methods , Phosphotransferases/chemistry , Algorithms , Genetic Predisposition to Disease , Humans , Machine Learning , Phosphorylation , Phosphotransferases/genetics , Software
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