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1.
Mol Cancer ; 20(1): 16, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33461590

RESUMO

BACKGROUND: The IκB kinase (IKK) complex, comprising the two enzymes IKKα and IKKß, is the main activator of the inflammatory transcription factor NF-κB, which is constitutively active in many cancers. While several connections between NF-κB signaling and the oncogene c-Myc have been shown, functional links between the signaling molecules are still poorly studied. METHODS: Molecular interactions were shown by co-immunoprecipitation and FRET microscopy. Phosphorylation of c-Myc was shown by kinases assays and its activity by improved reporter gene systems. CRISPR/Cas9-mediated gene knockout and chemical inhibition were used to block IKK activity. The turnover of c-Myc variants was determined by degradation in presence of cycloheximide and by optical pulse-chase experiments.. Immunofluorescence of mouse prostate tissue and bioinformatics of human datasets were applied to correlate IKKα- and c-Myc levels. Cell proliferation was assessed by EdU incorporation and apoptosis by flow cytometry. RESULTS: We show that IKKα and IKKß bind to c-Myc and phosphorylate it at serines 67/71 within a sequence that is highly conserved. Knockout of IKKα decreased c-Myc-activity and increased its T58-phosphorylation, the target site for GSK3ß, triggering polyubiquitination and degradation. c-Myc-mutants mimicking IKK-mediated S67/S71-phosphorylation exhibited slower turnover, higher cell proliferation and lower apoptosis, while the opposite was observed for non-phosphorylatable A67/A71-mutants. A significant positive correlation of c-Myc and IKKα levels was noticed in the prostate epithelium of mice and in a variety of human cancers. CONCLUSIONS: Our data imply that IKKα phosphorylates c-Myc on serines-67/71, thereby stabilizing it, leading to increased transcriptional activity, higher proliferation and decreased apoptosis.


Assuntos
Quinase I-kappa B/metabolismo , Inflamação/enzimologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Sequência de Aminoácidos , Animais , Apoptose/genética , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Células HEK293 , Humanos , Quinase I-kappa B/química , Inflamação/patologia , Masculino , Camundongos , Modelos Biológicos , Mutação/genética , Fosforilação , Fosfosserina/metabolismo , Fosfotreonina/metabolismo , Próstata/metabolismo , Ligação Proteica , Estabilidade Proteica , Transcrição Gênica
2.
Iran Biomed J ; 27(6): 388-96, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-38158635

RESUMO

Background: Many anogenital cancers are caused by high-risk HPV. The most common subtype is HPV16, which is prevalent in the world, including Pakistan. Various amino acid residues in HPV16 E5 are associated with high cell cycle progression and proliferation. Lack of studies on HPV16E5 in Pakistan prompted the current study. This is the first report on the occurrence of pathogenic E5 variant of HPV16 in tissue sections obtained from invasive cervical cancerous patients in Pakistan. Methods: A subset of 11 samples from HPV-positive biopsies were subjected to E5 gene amplification using PCR and analyzed using bioinformatics programs. The bioinformatics analysis detected mutations causing structural variations, which potentially contribute to the oncogenic properties of proteins. Results: The two-point mutations, C3979A and G4042A, observed in isolate 11 caused the substitution of isoleucine for leucine and valine at positions 44 and 65 in E5 protein. The rest of the isolates had Leu44Val65 amino acids. Intratypic variations and phylogenetic analysis revealed that the majority of the isolates were closely clustered with European-Asian lineage. Moreover, C3979A and G4042A contributed to higher degree of interactions with host receptors, i.e. EGFR. Conclusion: This is the first study reporting HPV16 variants in a Pakistani population based on variations in the E5 region. Our findings indicate that isolate 11 has a strong interaction with the intracellular domain of EGFR, which may enhance the generation of downstream signals. Since this was a pilot study to explore E5 gene mutation, future studies with large samples are absolutely needed.

3.
Inflamm Res ; 61(3): 177-88, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22277994

RESUMO

Toll-like receptors (TLRs) play a central role in the regulation of the host immune system. Each TLR recognizes specific pathogen-associated molecular patterns (PAMPs). TLR4 is one of the well characterized pathogen recognition receptors (PRRs) that recognizes the lipopolysaccharide (LPS) of Gram-negative bacteria, some conserved structures from fungal to mycobacterial pathogens and some endogenous ligands. A complex signaling cascade initiates after the ligand binds to the TLR4 ectodomain, leading to the activation of multiple inflammatory genes. Genetic variations greatly influence immune responses towards pathogenic challenges and disease outcome. In this review, we summarize various reports regarding TLR4 polymorphisms and disease susceptibility.


Assuntos
Predisposição Genética para Doença , Receptor 4 Toll-Like/genética , Animais , Doenças Transmissíveis/genética , Humanos , Lipopolissacarídeos/imunologia , Polimorfismo Genético , Transdução de Sinais , Receptor 4 Toll-Like/imunologia
4.
Immunol Res ; 69(4): 312-322, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34145551

RESUMO

Toll-like receptors 3 (TLR3) have been broadly studied among all TLRs over the last few decades together with its agonists due to their contribution to cancer regression. These agonists undeniably have some shared characteristics such as mimicking dsRNA but pathways through which they exhibit antitumor properties are relatively diverse. In this review, three widely studied agonists RGC100, ARNAX, and poly-IC are discussed along with their structural and physiochemical differences including the signaling cascades through which they exert their actions. Comparison has been made to identify the finest agonist with maximum effectivity and the least side effect profile.


Assuntos
Adjuvantes Imunológicos/farmacologia , Poli I-C/farmacologia , RNA/farmacologia , Receptor 3 Toll-Like/agonistas , Animais , Humanos
5.
Saudi J Biol Sci ; 28(9): 5359-5363, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34466115

RESUMO

Hepatitis C virus remained a public health problem with approximately half of the patients untreated and undiagnosed. Chronic HCV is a leading cause of cirrhosis, fibrosis, hepatocellular carcinoma and other hepatic morbidities. Active HCV has a prevalence rate of about 1% (71 million). By July, 2019, 10 million population of Pakistan was declared to have active HCV infection. According to World Health Organization, 23,720 people died of hepatitis-related complexities in Pakistan in 2016. Individuals with certain types of ABO blood groups were more susceptible to diverse kinds of infections. For instance, blood types A and AB predisposed individuals to severe malaria, while type O conferred resistance to the many of the protozoan agent. This study was designed to explore the association of hepatitis C viremia to blood groups, Rh factors, age and gender distribution among Pakistani population. Total 246 participants were screened for HCV in Taqwa diagnostics laboratory, Multan and 200 were found positive. They were divided into 4 groups on the basis of their age. First group included patients ranging from 17 to 25 (52), second, third and fourth group included patients from 26 to 34 (92), 35 to 43 (42) and 44 to above (14) respectively. Confirmed Hepatitis C patients were subjected to analysis of blood group, Rh factor and viral load. Results demonstrated that patients having 'O' blood group (60.37%) were reported for high viral load than any of the other blood groups in the patients of Southern Punjab, Pakistan. Furthermore, Rh-negative factor (26.42) was associated with high viral load than that of the Rh-positive factor (73.58). Disclosure practiced that age group (26-34) was reported for the high viral load than that of the any other group of this study. Females were more aggressively affected by HCV Viremia than male because the mean viral load among the females was higher than that of the males. Greater social awareness and gender-sensitive healthcare is necessary to improve the experiences of patients with HCV.

6.
Saudi J Biol Sci ; 28(6): 3548-3552, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34121897

RESUMO

Coronary artery disease (CAD) is the leading cause of sudden death worldwide. Inflammation is proved to be an important player in development of the CAD. Inflammation is directly regulated by the Toll like receptors (TLRs). Susceptibility of CAD is influenced by genetic variations within TLRs and the proteins involved in its signaling cascade. The TIRAP/MAL {TIR domain containing adaptor protein / MyD88 (myeloid differentiation primary response gene 88) adaptor-like} exhibits maximum genetic variations of all adaptor proteins involved in TLR signaling cascade. Susceptibility to a number of diseases can be influenced due to presence of S180L single nucleotide polymorphism (SNP) of TIRAP/MAL. This study was conducted to investigate the functional role of this well characterized S180L polymorphism on susceptibility to CAD among Pakistani patients. A total of 146 Pakistani CAD patients and 147 controls were genotyped by Amplification Refractory Mutation System-Polymerase Chain Reaction (ARMS-PCR) and the data was analyzed by using 2-tailed Chi square (x2 ) test. The p value ≤ 0.05 was considered to be significant. Significantly high frequency of homozygous L180L genotype was observed among healthy subjects as compared to the CAD patients [24 (16%) vs 7 (5%); x2 11.85; p = 0.003]. Moreover, the allele frequency of the minor allele; 180L was observed to be significantly higher among controls than the CAD patients, having same direction of association [156 (53%) vs 131 (45%); OR (95% CI) = 0.7198 (0.520-0.996); p < 0.05). Our results indicate that protective effect of L180L; a coding variant of TIRAP/MAL against CAD is discernible.

7.
APMIS ; 129(10): 579-586, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34342074

RESUMO

Coronavirus disease 2019 (COVID-19) is a novel respiratory disease that has led to a global pandemic and created a havoc. The COVID-19 disease severity varies among individuals, depending on fluctuating symptoms. Many infectious diseases such as hepatitis B and dengue hemorrhagic fever have been associated with ABO blood groups. The aim of this study was to explore whether ABO blood groups might serve as a risk or a protective factor for COVID-19 infection. Moreover, the symptomatic variations of COVID-19 infection among the individuals with different blood groups were also analyzed. An online questionnaire-based survey was conducted in which 305 partakers were included, who had successfully recovered from coronavirus infection. The ABO blood groups of 1294 healthy individuals were also taken as a control. The results of the current study demonstrated that antibody A containing blood groups (blood group B, p-value: 0.049 and blood group O, p-value: 0.289) had a protective role against COVID-19 infection. The comparison of symptomatic variations among COVID-19-infected subjects showed that blood group O subjects had lower chances of experiencing severe symptoms relating to respiratory distress, while subjects with AB blood group were more prone to develop symptoms, but the differences in both groups were found to be statistically non-significant. In conclusion, subjects who do not have anti-A antibodies in their serum (i.e., subjects with group A and AB) are more likely to be infected with COVID-19. The current data showed that there was no significant association of signs and symptoms variations of COVID-19 infection among individuals with different blood groups.


Assuntos
Sistema ABO de Grupos Sanguíneos , COVID-19/sangue , Adolescente , Adulto , Distribuição por Idade , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos de Casos e Controles , Suscetibilidade a Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Distribuição por Sexo , Inquéritos e Questionários , Adulto Jovem
8.
Viral Immunol ; 30(1): 20-27, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27830995

RESUMO

Viruses are the intracellular pathogens that reproduce only in the living cell and manipulate the cellular machinery to produce more viruses. Viral replications can affect cellular genes of the host in multiple cancerous ways. Approximately, 20% of all human oncogenesis is caused by cancer-causing viruses known as oncoviruses. Viral infection causes chronic inflammation leading to cell death, uncontrollable proliferation, and modulated expression of some of the regulatory proteins. Oncogenesis is a multistep phenomenon in which normal host cells are transformed into cancerous cells on the basis of host genetic variability. Oncogenic viruses encode genes that cause viral replication and transformation of the host cells to produce viral proteins and protein complexes. The phenomenon from basic viral infection to tumorigenesis is lengthy due to the involvement of factors like immunity complications, cellular mutations, and exposure to other cancerous agents. The viruses that are involved in human cancer development are Hepatitis B virus (HBV), Hepatitis C virus (HCV), Epstein-Barr virus (EBV), Human papilloma virus (HPV), Kaposi's sarcoma herpes virus (KSHV), and Human T lymphotrophic virus 1 (HTLV-1). This review article summarizes advanced knowledge related to human oncogenic viruses and the molecular mechanisms that lead to tumorigenesis in humans.


Assuntos
Carcinogênese , Transformação Celular Neoplásica , Interações Hospedeiro-Patógeno , Neoplasias/fisiopatologia , Neoplasias/virologia , Vírus Oncogênicos/patogenicidade , Humanos
9.
J Cancer Res Clin Oncol ; 142(12): 2497-2502, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27613186

RESUMO

PURPOSE: Over the past few decades, human papillomavirus (HPV) has been recorded as a key player in the development of various genital cancers, most notably cervical cancer. It has also been associated with some non-genital cancers. A subset of oropharyngeal cancers are known to be caused by HPV. Its aetiological involvement has been suggested for breast and lung cancer as well. However, reports regarding the HPV DNA detection vary widely from different parts of the world. Due to scarcity of local data in this regard, the current study aimed at retrospective detection of HPV presence in the archival samples of breast and lung cancer patients from north part of the country. METHODS: A total of 55 formalin-fixed paraffin-embedded tissue sections of invasive ductal carcinoma of breast (n = 46) and lung (n = 9) were collected for this study. Genotyping for HPV16 and 18 was carried out through PCR. RESULTS: HPV16 DNA was found in both breast and lung carcinoma samples with the prevalence rate of 17 and 11 %, respectively. An interesting association was found between ER/PR (Oestrogen/Progesterone receptor) and HER2/Neu (Human epidermal growth factor receptor-2) positivity with HPV occurrence in breast tumours. CONCLUSION: Current study shows the presence of HPV16 DNA in archived clinical biopsy sections from breast and lung cancers (17, 11 %), respectively. A positive correlation of HPV16 presence was found with ER/PR and HER2-positive breast cancers. These initial findings warrant further investigation in order to determine HPV prevalence and aetiological role in local cancers, especially in ER/PR/HER2-positive breast cancers on a larger scale.


Assuntos
Neoplasias da Mama/virologia , DNA Viral/isolamento & purificação , Papillomavirus Humano 16/isolamento & purificação , Neoplasias Pulmonares/virologia , Infecções por Papillomavirus/complicações , Adulto , Idoso , Neoplasias da Mama/complicações , Neoplasias da Mama/epidemiologia , Feminino , Papillomavirus Humano 16/genética , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/epidemiologia , Pessoa de Meia-Idade , Paquistão/epidemiologia , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/genética , Prevalência , Sistema de Registros , Estudos Retrospectivos
10.
Immunol Res ; 62(2): 234-52, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25784622

RESUMO

Toll like receptors (TLRs) play a crucial role in regulation of innate as well as adaptive immunity. TLRs recognize a distinct but limited repertoire of conserved microbial products. Ligand binding to TLRs activates the signaling cascade and results in activation of multiple inflammatory genes. Variation in this immune response is under genetic control. Polymorphisms in genes associated with inflammatory pathway especially influence the outcome of diseases. TLR2 makes heterodimer with TLR1 or TLR6 and recognizes a wide variety of microbial ligands. In this review, we summarize studies of polymorphisms in genes encoding TLR1, TLR2, TLR4, TLR6, and most polymorphic adaptor protein, Mal/TIRAP, revealing their effect on susceptibility to diseases.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Glicoproteínas de Membrana/genética , Polimorfismo Genético , Receptores de Interleucina-1/genética , Receptores Toll-Like/genética , Animais , Suscetibilidade a Doenças , Humanos , Ligantes , Glicoproteínas de Membrana/metabolismo , Receptores de Interleucina-1/metabolismo , Transdução de Sinais , Receptor 1 Toll-Like/genética , Receptor 1 Toll-Like/metabolismo , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptor 6 Toll-Like/genética , Receptor 6 Toll-Like/metabolismo , Receptores Toll-Like/metabolismo
11.
Asian Pac J Cancer Prev ; 16(3): 979-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25735392

RESUMO

Breast cancer is the leading cause of morbidity and mortality globally but has an even more significant impact in developing countries. Pakistan has the highest prevalence among Asian countries. A general lack of public awareness regarding the disease often results in late diagnosis and poor treatment outcomes. The literacy rate of the Southern Punjab (Pakistan) is low compared to its Northern part. It is therefore vital that university students and especially medical students develop a sound knowledge about the disease so that they can spread awareness to others who may be less educated. This study therefore considers current knowledge and understanding about the early signs of breast cancer amongst a study group of medical and non-medical university students of the Southern Punjab, Pakistan. A cross-sectional descriptive analysis of the university students was carried out using a self-administered questionnaire to assess their awareness of breast cancer from March to May 2014. A total of 566 students participated in this study, out of which 326 were non-medical and 240 were from a medical discipline. Statistical analysis was carried out using Graph Pad Prism Version 5 with a significance level set at p<0.05. The mean age of the non medical and medical participants was 23 (SD 2.1) and 22 (SD 1.3) years, respectively. Less than 35% students were aware of the early warning signs of the breast cancer development. Knowledge of medical students about risk factors was significantly better than the non medical ones, but on the whole was insufficient. Our study indicated that knowledge regarding breast cancer was generally insufficient amongst the majority of the university students (75% non-medical and 55% medical) of Southern Punjab, Pakistan. This study highlights the need to formulate an awareness campaign and to organize conferences to promote breast cancer awareness among students in this region.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Estudantes de Medicina/psicologia , Estudantes/psicologia , Adulto , Estudos Transversais , Feminino , Seguimentos , Humanos , Paquistão , Prognóstico , Fatores de Risco , Inquéritos e Questionários , Universidades , Adulto Jovem
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