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Advances in Experimental Medicine and... 2019DNA fragmentation, or the accumulation of single- and double-strand DNA breaks, is a common property of sperm, and an increase in the level of sperm DNA fragmentation is...
DNA fragmentation, or the accumulation of single- and double-strand DNA breaks, is a common property of sperm, and an increase in the level of sperm DNA fragmentation is known to influence natural reproduction. The effect of sperm DNA fragmentation on male infertility and assisted reproductive treatment (ART) outcomes remains controversial and is one of the most frequently debated topics of reproductive medicine. For the past 30 years, a number of assays have been developed to quantify the level of sperm DNA fragmentation. In this chapter, we review the causes of sperm DNA fragmentation, describe the commonly used tests to evaluate these abnormalities, and perform a systematic review of existing studies to determine the impact of sperm DNA fragmentation on male fertility and ART outcomes.
Topics: DNA Fragmentation; Female; Humans; Infertility, Male; Male; Reproduction; Reproductive Techniques, Assisted; Spermatozoa; Treatment Outcome
PubMed: 31301048
DOI: 10.1007/978-3-030-21664-1_6 -
International Journal of Molecular... Aug 2022Background: Glioblastoma (GBM) is a highly aggressive cancer with poor prognosis that needs better treatment modalities. Moreover, there is a lack of reliable biomarkers... (Meta-Analysis)
Meta-Analysis Review
Background: Glioblastoma (GBM) is a highly aggressive cancer with poor prognosis that needs better treatment modalities. Moreover, there is a lack of reliable biomarkers to predict the response and outcome of current or newly designed therapies. While several molecular markers have been proposed as potential biomarkers for GBM, their uptake into clinical settings is slow and impeded by marker heterogeneity. Detailed assessment of prognostic and predictive value for biomarkers in well-defined clinical trial settings, if available, is scattered throughout the literature. Here we conducted a systematic review and meta-analysis to evaluate the prognostic and predictive significance of clinically relevant molecular biomarkers in GBM patients. Material and methods: A comprehensive literature search was conducted to retrieve publications from 3 databases (Pubmed, Cochrane and Embase) from January 2010 to December 2021, using specific terms. The combined hazard ratios (HR) and confidence intervals (95% CI) were used to evaluate the association of biomarkers with overall survival (OS) in GBM patients. Results: Twenty-six out of 1831 screened articles were included in this review. Nineteen articles were included in the meta-analyses, and 7 articles were quantitatively summarised. Fourteen studies with 1231 GBM patients showed a significant association of MGMT methylation with better OS with the pooled HR of 1.66 (95% CI 1.32−2.09, p < 0.0001, random effect). Five studies including 541 GBM patients analysed for the prognostic significance of IDH1 mutation showed significantly better OS in patients with IDH1 mutation with a pooled HR of 2.37 (95% CI 1.81−3.12; p < 0.00001]. Meta-analysis performed on 5 studies including 575 GBM patients presenting with either amplification or high expression of EGFR gene did not reveal any prognostic significance with a pooled HR of 1.31 (95% CI 0.96−1.79; p = 0.08). Conclusions: MGMT promoter methylation and IDH1 mutation are significantly associated with better OS in GBM patients. No significant associations were found between EGFR amplification or overexpression with OS.
Topics: Biomarkers; Biomarkers, Tumor; Brain Neoplasms; DNA Methylation; DNA Modification Methylases; DNA Repair Enzymes; Glioblastoma; Humans; Tumor Suppressor Proteins
PubMed: 36012105
DOI: 10.3390/ijms23168835 -
Biochimica Et Biophysica Acta.... Jan 2023DNA methylation profiles are in dynamic equilibrium via the initiation of methylation, maintenance of methylation and demethylation, which control gene expression and... (Review)
Review
DNA methylation profiles are in dynamic equilibrium via the initiation of methylation, maintenance of methylation and demethylation, which control gene expression and chromosome stability. Changes in DNA methylation patterns play important roles in carcinogenesis and primarily manifests as hypomethylation of the entire genome and the hypermethylation of individual loci. These changes may be reflected in blood-based DNA, which provides a non-invasive means for cancer monitoring. Previous blood-based DNA detection objects primarily included circulating tumor DNA/cell-free DNA (ctDNA/cfDNA), circulating tumor cells (CTCs) and exosomes. Researchers gradually found that methylation changes in peripheral blood mononuclear cells (PBMCs) also reflected the presence of tumors. Blood-based DNA methylation is widely used in early diagnosis, prognosis prediction, dynamic monitoring after treatment and other fields of clinical research on cancer. The reversible methylation of genes also makes them important therapeutic targets. The present paper summarizes the changes in DNA methylation in cancer based on existing research and focuses on the characteristics of the detection objects of blood-based DNA, including ctDNA/cfDNA, CTCs, exosomes and PBMCs, and their application in clinical research.
Topics: Humans; DNA Methylation; Leukocytes, Mononuclear; Biomarkers, Tumor; Circulating Tumor DNA; Neoplasms; Cell-Free Nucleic Acids
PubMed: 36270476
DOI: 10.1016/j.bbadis.2022.166583 -
BMJ Open Jan 2016To measure test accuracy of non-invasive prenatal testing (NIPT) for Down, Edwards and Patau syndromes using cell-free fetal DNA and identify factors affecting accuracy. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To measure test accuracy of non-invasive prenatal testing (NIPT) for Down, Edwards and Patau syndromes using cell-free fetal DNA and identify factors affecting accuracy.
DESIGN
Systematic review and meta-analysis of published studies.
DATA SOURCES
PubMed, Ovid Medline, Ovid Embase and the Cochrane Library published from 1997 to 9 February 2015, followed by weekly autoalerts until 1 April 2015.
ELIGIBILITY CRITERIA FOR SELECTING STUDIES
English language journal articles describing case-control studies with ≥ 15 trisomy cases or cohort studies with ≥ 50 pregnant women who had been given NIPT and a reference standard.
RESULTS
41, 37 and 30 studies of 2012 publications retrieved were included in the review for Down, Edwards and Patau syndromes. Quality appraisal identified high risk of bias in included studies, funnel plots showed evidence of publication bias. Pooled sensitivity was 99.3% (95% CI 98.9% to 99.6%) for Down, 97.4% (95.8% to 98.4%) for Edwards, and 97.4% (86.1% to 99.6%) for Patau syndrome. The pooled specificity was 99.9% (99.9% to 100%) for all three trisomies. In 100,000 pregnancies in the general obstetric population we would expect 417, 89 and 40 cases of Downs, Edwards and Patau syndromes to be detected by NIPT, with 94, 154 and 42 false positive results. Sensitivity was lower in twin than singleton pregnancies, reduced by 9% for Down, 28% for Edwards and 22% for Patau syndrome. Pooled sensitivity was also lower in the first trimester of pregnancy, in studies in the general obstetric population, and in cohort studies with consecutive enrolment.
CONCLUSIONS
NIPT using cell-free fetal DNA has very high sensitivity and specificity for Down syndrome, with slightly lower sensitivity for Edwards and Patau syndrome. However, it is not 100% accurate and should not be used as a final diagnosis for positive cases.
TRIAL REGISTRATION NUMBER
CRD42014014947.
Topics: Biomarkers; Chromosome Disorders; Chromosomes, Human, Pair 13; Chromosomes, Human, Pair 18; DNA; Down Syndrome; Female; Humans; Pregnancy; Prenatal Diagnosis; Sensitivity and Specificity; Trisomy; Trisomy 13 Syndrome; Trisomy 18 Syndrome
PubMed: 26781507
DOI: 10.1136/bmjopen-2015-010002 -
Fertility and Sterility Dec 2023The impact of paternal obesity and metabolic disease on semen quality and fertility outcomes is not fully appreciated. With increasing obesity rates, researchers have... (Review)
Review
The impact of paternal obesity and metabolic disease on semen quality and fertility outcomes is not fully appreciated. With increasing obesity rates, researchers have studied the intricate relationship between paternal body mass index, metabolic health, and male fertility. This systematic review identified 112 articles in the MEDLINE database between 2013 and 2023 that investigated the effects of body mass index, diabetes, metabolic syndrome, exercise, weight loss medication, or bariatric surgery on semen parameters, sperm quality, or fertility outcomes. This review suggests that obesity, diabetes, and metabolic syndrome have a negative impact on various parameters of male fertility, from semen quality to sperm deoxyribonucleic acid integrity. There is also mounting evidence that male obesity is correlated negatively with live births via both natural conception and assisted reproductive technologies. Lifestyle interventions, such as physical exercise, generally appear to improve male fertility markers; however, the type and intensity of exercise may play a crucial role. Pharmacologic treatments for weight loss, such as metformin and glucagon-like peptide 1 agonists, present a more complex picture, with studies suggesting both beneficial and detrimental effects on male reproductive health. Similarly, surgical interventions, such as gastric bypass surgery, show promise in improving hormonal imbalances but have mixed effects on semen parameters. Future research is needed to clarify these associations and inform clinical guidelines. In the interim, health practitioners should incorporate these insights into clinical practices, encouraging proactive lifestyle changes and providing targeted treatments to improve male reproductive health.
Topics: Male; Humans; Semen Analysis; Semen; Metabolic Syndrome; Obesity; Infertility, Male; Fertility; Weight Loss; Diabetes Mellitus
PubMed: 37839720
DOI: 10.1016/j.fertnstert.2023.10.017 -
Brazilian Journal of Otorhinolaryngology 2021The association between uterine cervix and anogenital carcinomas and human papillomavirus, HPV, is well established, however the involvement of this virus in the... (Review)
Review
INTRODUCTION
The association between uterine cervix and anogenital carcinomas and human papillomavirus, HPV, is well established, however the involvement of this virus in the development of oral squamous cell carcinomas remains controversial.
OBJECTIVES
To evaluate the relationship between HPV infection and oral squamous cell carcinomas, and to estimate the incidence of this infection in these patients.
METHODS
Four electronic databases were searched to find studies that met the following inclusion criteria: i) performed in humans; ii) were cohort, case-control or cross-sectional; iii) assessed the HPV oncogenic activity by the E6 and E7 mRNA; iv) included primary oral squamous cell carcinomas which; v) diagnosis had been confirmed by biopsy. Information about the country; study period; sample obtainment; sites of oral squamous cell carcinomas; number, gender and age range of the population; the prevalence of HPV infection and subtypes detected; use of tobacco or alcohol and oral sex practice were extracted. The methodological quality of included articles was assessed using 14 criteria.
RESULTS
The search strategy retrieved 2129 articles. Assessment of the full text was done for 626 articles, but five were included. The total of participants included was 383, most of them male with mean age between 51.0 and 63.5 years old. Seventeen patients were HPV/mRNA-positive, being the subtypes 16 and 18 detected more frequently. Nine of the HPV/mRNA-positive oral squamous cell carcinomas occurred on the tongue. The quality score average of included articles was five points.
CONCLUSIONS
Among the 383 oral squamous cell carcinoma patients included, 17 (4.4%) were HPV/mRNA-positive, nevertheless it was not possible to assess if HPV infection was associated with oral squamous cell carcinomas because none of the studies included was longitudinal and cross-sectional investigations do not have control group.
Topics: Carcinoma, Squamous Cell; Cross-Sectional Studies; DNA, Viral; Female; Head and Neck Neoplasms; Humans; Male; Middle Aged; Mouth Neoplasms; Papillomaviridae; Papillomavirus Infections; Squamous Cell Carcinoma of Head and Neck
PubMed: 33339760
DOI: 10.1016/j.bjorl.2020.10.017 -
International Journal of Molecular... Jun 2023Emerging data have suggested that circulating tumor DNA (ctDNA) can be a reliable biomarker for minimal residual disease (MRD) in CRC patients. Recent studies have shown... (Meta-Analysis)
Meta-Analysis Review
Circulating Tumor DNA as a Minimal Residual Disease Assessment and Recurrence Risk in Patients Undergoing Curative-Intent Resection with or without Adjuvant Chemotherapy in Colorectal Cancer: A Systematic Review and Meta-Analysis.
Emerging data have suggested that circulating tumor DNA (ctDNA) can be a reliable biomarker for minimal residual disease (MRD) in CRC patients. Recent studies have shown that the ability to detect MRD using ctDNA assay after curative-intent surgery will change how to assess the recurrence risk and patient selection for adjuvant chemotherapy. We performed a meta-analysis of post-operative ctDNA in stage I-IV (oligometastatic) CRC patients after curative-intent resection. We included 23 studies representing 3568 patients with evaluable ctDNA in CRC patient post-curative-intent surgery. Data were extracted from each study to perform a meta-analysis using RevMan 5.4. software. Subsequent subgroup analysis was performed for stages I-III and oligometastatic stage IV CRC patients. Results showed that the pooled hazard ratio (HR) for recurrence-free survival (RFS) in post-surgical ctDNA-positive versus -negative patients in all stages was 7.27 (95% CI 5.49-9.62), < 0.00001. Subgroup analysis revealed pooled HRs of 8.14 (95% CI 5.60-11.82) and 4.83 (95% CI 3.64-6.39) for stages I-III and IV CRC, respectively. The pooled HR for RFS in post-adjuvant chemotherapy ctDNA-positive versus -negative patients in all stages was 10.59 (95% CI 5.59-20.06), < 0.00001. Circulating tumor DNA (ctDNA) analysis has revolutionized non-invasive cancer diagnostics and monitoring, with two primary forms of analysis emerging: tumor-informed techniques and tumor-agnostic or tumor-naive techniques. Tumor-informed methods involve the initial identification of somatic mutations in tumor tissue, followed by the targeted sequencing of plasma DNA using a personalized assay. In contrast, the tumor-agnostic approach performs ctDNA analysis without prior knowledge of the patient's tumor tissue molecular profile. This review highlights the distinctive features and implications of each approach. Tumor-informed techniques enable the precise monitoring of known tumor-specific mutations, leveraging the sensitivity and specificity of ctDNA detection. Conversely, the tumor-agnostic approach allows for a broader genetic and epigenetic analysis, potentially revealing novel alterations and enhancing our understanding of tumor heterogeneity. Both approaches have significant implications for personalized medicine and improved patient outcomes in the field of oncology. The subgroup analysis based on the ctDNA method showed pooled HRs of 8.66 (95% CI 6.38-11.75) and 3.76 (95% CI 2.58-5.48) for tumor-informed and tumor-agnostic, respectively. Our analysis emphasizes that post-operative ctDNA is a strong prognostic marker of RFS. Based on our results, ctDNA can be a significant and independent predictor of RFS. This real-time assessment of treatment benefits using ctDNA can be used as a surrogate endpoint for the development of novel drugs in the adjuvant setting.
Topics: Humans; Circulating Tumor DNA; Neoplasm, Residual; Chemotherapy, Adjuvant; Colorectal Neoplasms; Biomarkers, Tumor; Neoplasm Recurrence, Local
PubMed: 37373376
DOI: 10.3390/ijms241210230 -
The Lancet. Oncology Apr 2023Human papillomavirus (HPV) DNA and p16 positivity have crucial roles in the pathogenesis of vulvar cancer and vulvar intraepithelial neoplasia. We aimed to examine the... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Human papillomavirus (HPV) DNA and p16 positivity have crucial roles in the pathogenesis of vulvar cancer and vulvar intraepithelial neoplasia. We aimed to examine the pooled prevalence of HPV DNA and p16 positivity in vulvar cancer and vulvar intraepithelial neoplasia worldwide.
METHODS
In this systematic review and meta-analysis, we searched PubMed, Embase, and the Cochrane Library databases for studies published between Jan 1, 1986, and May 6, 2022, that reported the prevalence of HPV DNA, or p16 positivity, or both, in histologically verified vulvar cancer or vulvar intraepithelial neoplasia. Studies on a minimum of five cases were included. Study-level data were extracted from the published studies. Random effect models were used to examine the pooled prevalence of HPV DNA and p16 positivity in both vulvar cancer and vulvar intraepithelial neoplasia, which were further investigated using stratified analyses by histological subtype, geographical region, HPV DNA or p16 detection method, tissue sample type, HPV genotype, publication year, and age at diagnosis. Additionally, meta-regression was applied to explore sources of heterogeneity.
FINDINGS
We retrieved 6393 search results, of which 6233 were excluded for being duplicates or after application of our inclusion and exclusion criteria. We also identified two studies from manual searches of references lists. 162 studies were eligible for inclusion in the systematic review and meta-analysis. The prevalence of HPV in vulvar cancer (91 studies; n=8200) was 39·1% (95% CI 35·3-42·9) and in vulvar intraepithelial neoplasia (60 studies; n=3140) was 76·1% (70·7-81·1). The most predominant HPV genotype in vulvar cancer was HPV16 (78·1% [95% CI 73·5-82·3]), followed by HPV33 (7·5% [4·9-10·7]). Similarly, HPV16 (80·8% [95% CI 75·9-85·2]) and HPV33 (6·3% [3·9-9·2]) were also the most two predominant HPV genotypes in vulvar intraepithelial neoplasia. The distribution of type-specific HPV genotypes in vulvar cancer among geographical regions was different, with HPV16 varying between regions, showing a high prevalence in Oceania (89·0% [95% CI 67·6-99·5]) and a low prevalence in South America (54·3% [30·2-77·4]). The prevalence of p16 positivity in patients with vulvar cancer was 34·1% (95% CI 30·9-37·4; 52 studies; n=6352), and it was 65·7% (52·5-77·7; 23 studies; n=896) in patients with vulvar intraepithelial neoplasia. Furthermore, among patients with HPV-positive vulvar cancer, p16 positivity prevalence was 73·3% (95% CI 64·7-81·2), compared with 13·8% (10·0-18·1) in HPV-negative vulvar cancer. The prevalence of double positivity for HPV and p16 was 19·6% (95% CI 16·3-23·0) in vulvar cancer and 44·2% (26·3-62·8) in vulvar intraepithelial neoplasia. Most analyses had large heterogeneity (I>75%).
INTERPRETATION
The high prevalence of HPV16 and HPV33 in vulvar cancer and vulvar intraepithelial neoplasia emphasised the importance of nine-valent HPV vaccination in preventing vulvar neoplasm. Additionally, this study highlighted the potential clinical significance of double positivity for HPV DNA and p16 in vulvar neoplasm.
FUNDING
Taishan Scholar Youth Project of Shandong Province, China.
Topics: Female; Humans; Adolescent; Vulvar Neoplasms; Cyclin-Dependent Kinase Inhibitor p16; Human Papillomavirus Viruses; DNA, Viral; Prevalence; Papillomavirus Infections; Carcinoma in Situ; Carcinoma, Squamous Cell; Papillomaviridae; Human papillomavirus 16
PubMed: 36933562
DOI: 10.1016/S1470-2045(23)00066-9 -
Cancer Treatment Reviews Mar 2022Circulating tumor DNA (ctDNA) is increasingly being used as a biomarker in early breast cancer (EBC). We performed a systematic review and meta-analysis to investigate... (Meta-Analysis)
Meta-Analysis Review
Circulating tumor DNA (ctDNA) is increasingly being used as a biomarker in early breast cancer (EBC). We performed a systematic review and meta-analysis to investigate the prognostic value of ctDNA in patients with EBC treated with neoadjuvant therapy (NAT). We searched Medline, Web of Science and Embase for observational or interventional studies that included patients with EBC undergoing NAT, reported outcomes related to the predefined endpoints, and had full text articles available. Study selection followed the PRISMA guidelines and quality assessment the REMARK tool for biomarker studies. Primary endpoint was impact of ctDNA detection in different time points (baseline, on-treatment, and after NAT) on relapse-free survival (RFS) and overall survival (OS). Secondary endpoints included the association of ctDNA detection with pathologic complete response (pCR), and the positive and negative predictive value of ctDNA detection in predicting residual disease after NAT. From the 2908 studies initially identified, 11 met the eligibility criteria and were included in the meta-analysis. Detection of ctDNA, both at baseline and after completion of NAT, significantly associated to worse RFS (HR 4.22, 95% CI: 1.29-13.82 and HR 5.67, 95% CI: 2.73-11.75, respectively) and worse OS (HR 19.1, 95% CI: 6.9-53.04 and HR 4.00, 95% CI: 1.90-8.42, respectively). In contrast, detection of ctDNA did not associate with the probability of achieving a pCR. Our results suggest that ctDNA assessment during NAT for EBC merits further evaluation as a stratification risk factor in prospective trials, in order to better individualize patient's treatment.
Topics: Breast Neoplasms; Circulating Tumor DNA; Female; Humans; Neoadjuvant Therapy; Neoplasm Recurrence, Local; Prognosis; Prospective Studies
PubMed: 35219090
DOI: 10.1016/j.ctrv.2022.102362 -
The Lancet. Gastroenterology &... Oct 2022Despite growing concerns about transmissibility and clinical impact, occult hepatitis B virus (HBV) infection has received little attention in the hepatitis elimination... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Despite growing concerns about transmissibility and clinical impact, occult hepatitis B virus (HBV) infection has received little attention in the hepatitis elimination agenda. We aimed to estimate the prevalence of occult HBV infection at a global and regional scale and in specific populations.
METHODS
For this systematic review and meta-analysis, we searched the MEDLINE, Embase, Global Health, and Web of Science databases for articles published in any language between Jan 1, 2010, and Aug 14, 2019. We included original articles and conference abstracts of any study design that reported the proportion of HBsAg-negative adults (aged ≥18 years) who are positive for HBV DNA (ie, people with occult HBV infection). The prevalence of occult HBV infection was pooled, using the DerSimonian-Laird random-effects model, in the general population and specific groups defined by the type of study participants (blood donors; other low-risk populations; high-risk populations; and people with advanced chronic liver disease), and stratified by HBV endemicity in each country. We also assessed the performance of anti-HBc as an alternative biomarker to detect occult HBV infection. The study was registered with PROSPERO, CRD42019115490.
FINDINGS
305 of 3962 articles were eligible, allowing a meta-analysis of 140 521 993 individuals tested for HBV DNA. Overall, only two studies evaluated occult HBV infection in the general population, precluding unbiased global and regional estimates of occult HBV infection prevalence. In blood donors, occult HBV infection prevalence mirrored HBV endemicity: 0·06% (95% CI 0·00-0·26) in low-endemicity countries, 0·12% (0·04-0·23) in intermediate-endemicity countries, and 0·98% (0·44-1·72), in high-endemicity countries (p=0·0012). In high-risk groups, occult HBV infection prevalence was substantial, irrespective of endemicity: 5·5% (95% CI 2·9-8·7) in low-endemicity countries, 5·2% (2·5-8·6) in intermediate-endemicity countries, and 12·0% (3·4-24·7) in high-endemicity countries. The pooled sensitivity of anti-HBc to identify occult HBV infection was 77% (95% CI 62-88) and its specificity was 76% (68-83).
INTERPRETATION
A substantial proportion of people carry occult HBV infection, especially among high-risk groups across the globe and people living in highly endemic countries. Occult HBV infection should be part of the global viral hepatitis elimination strategy.
FUNDING
None.
Topics: Adolescent; Adult; DNA, Viral; Hepatitis B; Hepatitis B Antibodies; Hepatitis B virus; Hepatitis B, Chronic; Humans; Prevalence
PubMed: 35961359
DOI: 10.1016/S2468-1253(22)00201-1