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Impact of utilizing p16INK4A immunohistochemistry on estimated performance of three cervical cancer screening tests.

The histopathological diagnosis of cervical intraepithelial neoplasia grade 2,3 (CIN 2,3) is subjective and prone to variability. In our study, we analyzed the impact of utilizing a biomarker (p16(INK4A)) together with histopathology to refine the "gold standard" utilized for evaluating the performance of 3 different cervical cancer screening tests: cervical cytology, human papillomavirus (HPV) DNA testing and visual inspection with acetic acid (VIA). Cervical biopsies from 2 South African cervical cancer screening studies originally diagnosed by a single pathologist were reevaluated by a second pathologist and a consensus pathology diagnosis obtained. Immunohistochemical staining for p16(INK4A) was then performed. The estimated sensitivity of some cervical cancer screening tests was markedly impacted by the criteria utilized to define CIN 2,3. Use of routine histopathology markedly underestimated the sensitivity of both conventional cytology and HPV DNA testing compared to an improved gold standard of consensus pathology and p16(INK4A) positivity. In contrast, routine histopathology overestimated the sensitivity of VIA. Our results demonstrate that refining the diagnosis of CIN 2,3 through the use of consensus pathology and immunohistochemical staining for p16(INK4A) has an important impact on measurement of the performance of cervical cancer screening tests. The sensitivity of screening tests such as HPV DNA testing and conventional cytology may be underestimated when an imperfect gold standard (routine histopathology) is used. In contrast, the sensitivity of other tests, such as VIA, may be overestimated with an imperfect gold standard.

Cyclin-Dependent Kinase Inhibitor p16↗

Response profiles to fluticasone and montelukast in mild-to-moderate persistent childhood asthma.

BACKGROUND: Outcome data are needed to base recommendations for controller asthma medication use in school-aged children. OBJECTIVE: We sought to determine intraindividual and interindividual response profiles and predictors of response to an inhaled corticosteroid (ICS) and a leukotriene receptor antagonist (LTRA). METHODS: An ICS, fluticasone propionate (100 mug twice daily), and an LTRA, montelukast (5-10 mg nightly, age dependent), were administered to children ages 6 to 17 years with mild-to-moderate persistent asthma using only as-needed bronchodilators in a multicenter, double-masked, 2-sequence, 16-week crossover trial. Clinical, pulmonary, and inflammatory responses to these controllers were evaluated. RESULTS: Improvements in most clinical asthma control measures occurred with both controllers. However, clinical outcomes (asthma control days [ACDs], the validated Asthma Control Questionnaire, and albuterol use), pulmonary responses (FEV(1)/forced vital capacity, peak expiratory flow variability, morning peak expiratory flow, and measures of impedance), and inflammatory biomarkers (exhaled nitric oxide [eNO]) improved significantly more with fluticasone than with montelukast treatment. eNO was both a predictor of ACDs (P = .011) and a response indicator (P = .003) in discriminating the difference in ACD response between fluticasone and montelukast. CONCLUSIONS: The more favorable clinical, pulmonary, and inflammatory responses to an ICS than to an LTRA provide pediatric-based group evidence to support ICSs as the preferred first-line therapy for mild-to-moderate persistent asthma in children. eNO, as a predictor of response, might help to identify individual children not receiving controller medication who achieve a greater improvement in ACDs with an ICS compared with an LTRA.

Acetates↗

Prognostic relevance of histological grade and its components in node-negative breast cancer patients.

Available results highlight the lack of good level of evidence studies on the pure prognostic value of histological grade. In the present study, the prognostic relevance of histological grade and of its three components, tubule formation, nuclear pleomorphism and mitotic count, was analyzed in a series of 372 patients with node-negative breast cancer treated with locoregional therapy alone until early relapse. Histological grade was determined blindly by two observers and discordance between evaluations was resolved after joint review using a multihead microscope. No relation was observed between histological grade and any of its three components and disease-free survival. Conversely, a significant relation was observed between histological grade and distant metastasis-free survival (at 6 years, 94, 86 and 76% for grades 1, 2 and 3, respectively, P=0.013) as well as overall survival (98, 90 and 86%, P=0.001). A breakdown analysis as a function of the three components showed that neither tubule formation nor nuclear pleomorphism was associated with prognosis, and only mitotic count strongly influenced both distant metastasis-free survival (91, 82 and 74%, P=0.014) and overall survival (97, 87 and 85%, P=0.011). Histological grade suffers from a much higher subjectivity than any other microscopic evaluation of biomarkers as it is the sum of three different morphological features. Within the Italian Network for Quality Assessment of Tumor Biomarkers program we observed that histological grade is an independent prognostic variable, but also that this role is ascribable only to the number of mitotic figures. In conclusion, due to the ever smaller size of diagnosed breast cancers, resulting in less cancer tissue for biofunctional and molecular analysis, mitotic count evaluated under strict quality control conditions seems to be an accurate and feasible prognostic variable.

Adult↗

CRISPR-Cas9‑based lipid nanocarriers for advanced therapy of urinary bladder cancer.

Bladder cancer (BCa) exhibits significant genetic and phenotypic variability. This variability suggests that various tumor subtypes could be influenced by several biomarkers and signaling pathways, which presents a problem for monotherapy strategies. Despite the initial effectiveness of traditional therapies, BCa's high rates of progression and recurrence, and the eventual development of drug resistance in many patients, continue to be major concerns. Because of the potential to transform the genetic modifications linked to the disease, genome editing using CRISPR/Cas9 has become a transformative tool in medicine with noteworthy potential for BCa therapy. Although the CRISPR/Cas9 technology is incredibly effective at transforming the field of genome editing, its instability and cellular impermeability pose significant challenges to its delivery. To increase efficient delivery of CRISPR/Cas9, nanovectors may be investigated. Significant promise exists for improving the therapeutic potential of CRISPR-Cas9 technology and addressing complex cancer therapy difficulties because of the rapid development of nanotechnology-based delivery systems. Relevant articles were searched in Google Scholar, Scopus, and Web of Science covering studies published between 2007 and 2026. Along with the impact of lipid-based nanoparticles on their safe transport to cancer cells, this review emphasizes the significance of the CRISPR/Cas9 genome editing system in the treatment of BCa.

CRISPR–Cas9↗

Smoking and high-risk mammographic parenchymal patterns: a case-control study.

STATEMENT OF FINDINGS: Current smoking was strongly and inversely associated with high-risk patterns, after adjustment for concomitant risk factors. Relative to never smokers, current smokers were significantly less likely to have a high-risk pattern. Similar results were obtained when the analysis was confined to postmenopausal women. Past smoking was not related to the mammographic parenchymal patterns. The overall effect in postmenopausal women lost its significance when adjusted for other risk factors for P2/DY patterns that were found to be significant in the present study, although the results are still strongly suggestive. The present data indicate that adjustment for current smoking status is important when evaluating the relationship between mammographic parenchymal pattern and breast cancer risk. They also indicate that smoking is a prominent potential confounder when analyzing effects of other risk factors such as obesity-related variables. It appears that parenchymal patterns may act as an informative biomarker of the effect of cigarette smoking on breast cancer risk.

Breast Neoplasms↗

Influence of metal (Cd and Zn) waterborne exposure on radionuclide (134Cs, 110Ag, and 57Co) bioaccumulation by rainbow trout (Oncorhynchus mykiss): a field and laboratory study.

Field and laboratory experiments were carried out to assess the influence of Cd and Zn on the contamination levels of 110Ag, 57Co, and 134Cs in rainbow trout. During a four-week prior exposure phase, two fish groups were held in tanks in the Lot River (France) at a reference (<0.05 microg Cd/L and 68 microg Zn/L) and at a polluted site (1.5 microg Cd/L and 152 microg Zn/L). During a subsequent phase, organisms were brought back to the laboratory, where the radionuclide accumulation and depuration were studied for 14 and 7 d, respectively. During this second phase, the water used in the experiments was brought back from the two sites on the Lot River in order to work under the same chemical conditions. The potential effect of chronic exposure to stable metals on several biomarkers has been explored: Plasma analysis indicated the disruption of certain variables linked to the energetic metabolism and to the maintenance of the ionic balance. In contrast, no significant disruption of the measured enzyme activities was observed. With regard to the bioaccumulation of radionuclides, concentrations in fish exposed to metals are much lower than those in fish from the control group. Various hypotheses are proposed to link fish metabolic profiles due to metal exposure to the radiocontamination of organisms.

Animals↗

DNA single strand breakage, DNA adducts, and sister chromatid exchange in lymphocytes and phenanthrene and pyrene metabolites in urine of coke oven workers.

OBJECTIVES: To investigate the specificity of biological monitoring variables (excretion of phenanthrene and pyrene metabolites in urine) and the usefulness of some biomarkers of effect (alkaline filter elution, 32P postlabelling assay, measurement of sister chromatid exchange) in workers exposed to polycyclic aromatic hydrocarbons (PAHs). METHODS: 29 coke oven workers and a standardised control group were investigated for frequencies of DNA single strand breakage, DNA protein cross links (alkaline filter elution assay), sister chromatid exchange, and DNA adducts (32P postlabelling assay) in lymphocytes. Phenanthrene and pyrene metabolites were measured in 24 hour urine samples. 19 different PAHs (including benzo(a)pyrene, pyrene, and phenanthrene) were measured at the workplace by personal air monitoring. The GSTT1 activity in erythrocytes and lymphocyte subpopulations in blood was also measured. RESULTS: Concentrations of phenanthrene, pyrene, and benzo(a)pyrene in air correlated well with the concentration of total PAHs in air; they could be used for comparisons of different workplaces if the emission compositions were known. The measurement of phenanthrene metabolites in urine proved to be a better biological monitoring variable than the measurement of 1-hydroxypyrene. Significantly more DNA strand breaks in lymphocytes of coke oven workers were found (alkaline filter elution assay); the DNA adduct rate was not significantly increased in workers, but correlated with exposure to PAHs in a semiquantitative manner. The number of sister chromatid exchanges was lower in coke oven workers but this was not significant; thus counting sister chromatid exchanges was not a good variable for biomonitoring of coke oven workers. Also, indications for immunotoxic influences (changes in lymphocyte subpopulations) were found. CONCLUSIONS: The measurement of phenanthrene metabolites in urine seems to be a better biological monitoring variable for exposure to PAHs than measurement of hydroxypyrene. The alkaline filter elution assay proved to be the most sensitive biomarker for genotoxic damage, whereas the postlabelling assay was the only one with some specificity for DNA alterations caused by known compounds.

Adult↗

Screening of single-chain variable fragments against TSP50 from a phage display antibody library and their expression as soluble proteins.

A novel gene, testes-specific protease 50 (TSP50), is abnormally activated and differentially expressed in most patients with breast cancer, suggesting it as a novel biomarker for this disease. The possibility that TSP50 may be an oncogene is presently under investigation. In this study, the single-chain variable fragments (scFvs) against TSP50 were panned from a phage display antibody library using TSP50-specific peptide, pep-50, as a target antigen. After 4 rounds of panning, 3 clones (A1, A11, and C8) from the library were verified to show strong binding affinities for TSP50 by enzyme-linked immunosorbent assay (ELISA) and to contain the variable region genes of the light and heavy chains of scFv antibodies but different complementary determining regions by sequencing. The genes of scFv-A1 and scFv-A11 were cloned into expression vector pPELB and successfully expressed as a soluble protein inEscherichia coli Rosetta. The yields of expressions were about 4.0 to 5.0 mg of protein from 1 L of culture. The expressed proteins were purified by a 2-step procedure consisting of ion-exchange chromatography, followed by immobilized metal affinity chromatography. The purified proteins were shown a single band at the position of 31 KDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Sandwich ELISA demonstrated that the expressed scFv proteins were able to specifically react with pep-50, laying a foundation for the investigation of the function of TSP50 in the development and treatment of breast cancer.

Animals↗

Use of metallothionein in gills from oysters (Crassostrea gigas) as a biomarker: seasonal and intersite fluctuations.

The use of oyster gills for the analytical determination of metallothionein (MT) concentration as a biomarker of metal exposure was investigated. Temporal variations in MT and metal concentrations (which can interfere with inter-site differences) were examined over a 7 month period (from spring to autumn) in Japanese oysters from a clean site (Bay of Bourgneuf, France) and a metal-rich site (Gironde estuary, France) as well as in individuals translocated from the clean to the contaminated area. The ratio between the annual average of MT concentrations in specimens from the clean and the metal-rich sites was 1.3. During the last 3 months of the experiment, significant differences were no longer registered between transplants and residents from the Gironde estuary. Metals concentrations in oyster gills differed consistently between the clean and the metal-rich sites (annual average ratios of 1.5, 2.7 and 9.8, respectively, for zinc, copper and cadmium) and a fast increase in metal concentrations (over a few months) was observed in transplants, mainly for cadmium. MT and soluble metal concentrations were found to be positively and significantly correlated over the period of the study. This relationship is a positive argument for a possible use of gill MT concentration as a biomarker of metal pollution in contrast to previous findings on the digestive gland, there being a smaller amount of seasonal variability in the weight of oyster gills.

Animals↗

Can we identify a 'high risk' patient profile to determine who will experience rapid progression of osteoarthritis?

Disease modifying drugs for osteoarthritis (OA) that may halt or retard joint destruction and at the same time possibly improve symptoms are being developed and tested at various stages in clinical trials. This has, for at least two reasons, focused attention on the need for identification of patient groups at high risk for incident or progressive OA. First, well characterized such groups may be useful in clinical trials. Second, assuming that disease modifying OA drugs become available in the future, primary target groups in need of such therapy have to be identified. Risk factors for incident OA may differ from those for OA progression. Interactions between risk factors for OA is little understood. Factors that have consistently been reported as associated with radiographic OA progression are obesity, generalized OA, alignment and synovitis. Other factors such as bone scintigraphic lesions, joint injury nad biomarkers (such as type II collagen fragments, COMP and HA) show promise. Further evaluation of these variables and their individual and combined influence will be useful to design a risk profile for OA incidence and progression.

Biomarkers↗

AI-driven diagnostic and prognostic models for metabolic dysfunction-associated steatotic liver disease: insights from clinical, imaging, and multi-omics studies-a scoping review.

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), is the most common chronic liver disease around the world, affecting 33.6% of the adult population (95% CI: 28.1%-39.5%; I 2&#x2009;=&#x2009;99.9%), or roughly one in three. The extent of the liver damage is variable, from simple steatosis to metabolic dysfunction-associated steatohepatitis (MASH, formerly NASH), cirrhosis and hepatocellular carcinoma (HCC). Early diagnosis is essential to prevent serious liver damage. Traditional diagnostic techniques such as liver biopsy, imaging, and biomarker testing are all invasive, costly, reduced sensitive to early-stage disease, and they also have variability among observers. Modern diagnostic and prognostic approaches based on the principles of Artificial Intelligence (AI) and specifically on machine learning (ML) and deep learning (DL) have enabled multimodal approaches integrating clinical, imaging and molecular data. This scoping review conducted per PRISMA-ScR guidelines, synthesizes findings from 73 studies (search window 2020-2026) across three dimensions: clinical data driven models, imaging-based classifiers (ultrasound, CT and MRI), and multi-omics (genomics, transcriptomics and proteomics) techniques. Moreover, emergence of models such as U-Net and LiverNet 2.x, classification models like DeepLiverNet and BiLSTM models, as well as transformer frameworks and the identification of biomarkers models are also described. This study also investigates challenges such as data heterogeneity, data interpretability, fairness and real-world clinical application. Finally, important areas of research opportunities and future directions are highlighted to present a developing clinically applicable, explainable and ethical AI solutions to manage MASLD.

MASLD↗

Biomarkers of oxidative damage in human disease.

Oxidative/nitrosative stress, a pervasive condition of increased amounts of reactive oxygen/nitrogen species, is now recognized to be a prominent feature of many acute and chronic diseases and even of the normal aging process. However, definitive evidence for this association has often been lacking because of recognized shortcomings with biomarkers and/or methods available to assess oxidative stress status in humans. Emphasis is now being placed on biomarkers of oxidative stress, which are objectively measured and evaluated as indicators of normal biological processes, pathogenic processes, or pharmacologic responses to therapeutic intervention. To be a predictor of disease, a biomarker must be validated. Validation criteria include intrinsic qualities such as specificity, sensitivity, degree of inter- and intraindividual variability, and knowledge of the confounding and modifying factors. In addition, characteristics of the sampling and analytical procedures are of relevance, including constraints and noninvasiveness of sampling, stability of potential biomarkers, and the simplicity, sensitivity, specificity, and speed of the analytical method. Here we discuss some of the more commonly used biomarkers of oxidative/nitrosative damage and include selected examples of human studies.

Biomarkers↗

Effect of creatinine and specific gravity normalization techniques on xenobiotic biomarkers in smokers' spot and 24-h urines.

Renal excretion mechanisms are xenobiotic-specific; therefore, accurate exposure assessment requires an understanding of relationships of xenobiotic biomarker concentration and excretion rate to urine flow, specific gravity and creatinine concentration. Twenty-four-hour urine collection for xenobiotic exposure assessment is considered the "gold standard" procedure. Random spot-urine collection is convenient and minimizes subject compliance concerns but requires that normalization techniques be employed to account for diuresis and diurnal variation in xenobiotic biomarker excretion. This paper examines and makes recommendations concerning normalization techniques and conditions under which spot-urine results most accurately reflect 24-h urine results. Specific gravity, creatinine, and xenobiotic biomarkers were determined in smokers' spot and 24-h urines. Normalization techniques were applied, variance-component analyses were performed to estimate variability, spot urines were pooled mathematically to simulate 24-h urines and analyses of variance were performed to evaluate spot urines' ability to reflect 24-h urine concentrations. For each xenobiotic biomarker concentration, log-linear relationships were observed with urine flow, specific gravity, and creatinine. For most xenobiotic biomarker excretion rates, log-linear relationships were observed with urine flow; creatinine, however, was unaffected by urine flow. The conventional creatinine ratio-normalization technique demonstrated greater variability (within-day, between-day and between-subject) than other normalization techniques. Comparisons of simulated 24-h urines to spot urines suggest that spot-urine collection be performed only between 2 p.m. and 2 a.m. and that the modified specific-gravity-adjusted-creatinine ratio-normalization technique and the creatinine-regression normalization technique yield the best agreement between spot- and simulated 24-h urine results.

Biomarkers↗

Breath biomarkers and non-alcoholic fatty liver disease: preliminary observations.

Breath biomarkers have the potential to offer information that is similar to conventional clinical tests or they are entirely unique. Preliminary data support the use of breath biomarkers in the study of liver disease, in particular non-alcoholic fatty liver disease (NAFLD). It was evaluated whether breath ethanol, ethane, sulfur compounds and acetone would be associated with hepatic histopathology amongst morbidly obese patients presenting for bariatric surgery. Breath samples were collected during a preoperative visit and compared with liver biopsies obtained during the surgery. A Student's two-tailed t-test was used to compare differences between the two groups. Linear regression was used to analyse associations between the concentrations of breath molecules and independent predictor variables. It was found that breath ethanol, ethane and acetone can be useful biomarkers in patients with NAFLD. In particular, breath ethanol can be associated with hepatic steatosis, and breath acetone can be associated with non-alcoholic steatohepatitis.

Acetone↗

Patient-related variables predicting acute coronary syndrome following admission for chest pain of possible coronary origin.

OBJECTIVE: Improving risk stratification of patients experiencing acute chest pain with non-revealing electrocardiogram and cardiac biomarkers could reduce missed acute coronary syndrome and avoid unnecessary hospitalization. METHODS: We assessed the ability of situational, circumstantial, and other patient-related variables in predicting acute coronary syndrome in 921 consecutive patients randomly admitted to this medical department with chest pain of possible coronary origin. A reference group comprised 107 patients referred promptly to the coronary care unit with acute myocardial infarction. RESULTS: Acute coronary syndrome eventually developed in 219 (23.7%) patients. Age and proportions of male patients and those with diabetes, which were significantly lower in the heterogeneous chest pain group than in the reference group, did not differ when re-evaluation was performed between the latter group and the subgroup of patients who eventually developed acute coronary syndrome. Overweight and a family history of premature coronary artery disease remained significantly higher in the reference group, while prevalence of pre-existing coronary artery disease, previous coronary angiography, and coronary intervention remained significantly lower. Variables most significantly predictive of acute coronary syndrome resulted: pre-existing coronary artery disease [odds ratio (OR) 3.2; 95% confidence interval (CI) 2.17-4.71; P<0.001), older age (OR 1.35; 95% CI 1.17-1.57; P<0.001), male sex (OR 1.77; 95% CI 1.19-2.61; P=0.004), diabetes (OR 1.6; 95% CI 1.11-2.32; P=0.01), self-initiation of pain relief treatment before seeking medical help (OR 1.54; 95% CI 1.07-2.23; P=0.02), and conviction that hospitalization for acute coronary disease was mandatory (OR 1.46; 95% CI 1.03-2.07; P=0.03). CONCLUSIONS: Easily obtainable patient-related variables might improve risk stratification and assist physicians to decide on policy in the emergency department and upon hospitalization.

Acute Disease↗

Large-scale proteomics profiling of peripheral blood of DM1 patients identifies biomarkers for disease severity and functional capacity.

BackgroundMyotonic Dystrophy Type 1 (DM1), the most common genetic neuromuscular disorder in adults, poses significant challenges for drug development due to its multisystem nature and high clinical variability in symptoms and disease progression. With a growing number of therapies entering clinical trials, this study addresses the urgent need for biomarkers that can serve as surrogate endpoints.MethodsWe profiled 437 serum samples from adult DM1 patients collected at two timepoints of the OPTIMISTIC trial using bottom-up mass spectrometry with data-independent acquisition. Associations between protein expression, the disease-causing CTG-repeat and 25 clinical outcome measures were studied using linear mixed-effect models. All key study findings were validated in an independent cohort of 69 DM1 patients and 10 healthy controls.ResultsOf the 259 identified proteins, 161 showed significant associations with the CTG-repeat length (FDR&#x2009;<&#x2009;5%). Hypogammaglobulinemia was confirmed and shown to be worse in severely affected patients. A strong proteomic signature was associated with clinical measures of functional capacity, with the 6-Minute Walk Test showing the strongest signal (70 associations, FDR&#x2009;<&#x2009;5%). These novel associations reveal a compelling link between chronic inflammation and reduced functional capacity. A machine learning algorithm identified a minimal set of 13 proteins robustly reflecting both the underlying genetic defect and functional capacity.ConclusionsDM1 induces a broad disease fingerprint in the serum proteome, predominantly affecting proteins of the immune system. A carefully selected panel of proteins showed the greatest potential to meet the statistical criteria required for surrogate endpoints in clinical trials.

Humans↗

Interpretation of serum ferritin concentrations as indicators of total-body iron stores in survey populations: the role of biomarkers for the acute phase response.

BACKGROUND: Nutritional surveys use acute phase protein (APP) biomarkers such as C-reactive protein (CRP) and alpha1-acid glycoprotein (AGP) to identify the influence of inflammation on the distribution of iron status biomarkers. Few, however, have examined which biomarker better identifies persons with spurious elevations in iron status markers. OBJECTIVE: We explored the relations of APP biomarkers to iron-status biomarkers in infants and school-age children. DESIGN: In screening surveys, we identified a sample of African American infants (n = 351) and Guatemalan school-age children (n = 375). We used a common set of APP and iron-status biomarkers to examine the association between the 2 sets of markers (laboratory variables). RESULTS: The overall prevalence of either inflammation or iron deficiency was <10% in both samples. The log AGP and CRP values were significantly correlated (r = 0.70), but the unexplained variance still was >50%. Serum ferritin-but not transferrin receptor, transferrin receptor index, or serum iron-was related to APP concentrations, but poor positive predictive value (<72%) and low kappa scores were found. Ferritin concentrations >1 geometric SD above the geometric mean were poorly predicted by either elevated AGP or CRP. Qualitative CRP analysis was not effective in identifying persons who had other indications of mild inflammation. CONCLUSIONS: These analyses show that a low prevalence of inflammation has little influence on the distribution of ferritin, and 2 common indicators of inflammation do not perform equally well in identifying persons who may have elevations in ferritin due to inflammation.

Acute-Phase Proteins↗

M17, a gene specific for germinal center (GC) B cells and a prognostic marker for GC B-cell lymphomas, is dispensable for the GC reaction in mice.

In T-cell-dependent antibody responses, antigen-specific B cells undergo a phase of secondary antibody diversification in germinal centers (GCs). Somatic hypermutation (SHM) introduces mutations into the rearranged immunoglobulin (Ig) variable (V) region genes, and class-switch recombination (CSR) alters the Ig heavy (H) chain constant region. Aberrant SHM or CSR is thought to contribute to the development of GC-derived B-cell malignancies. Diffuse large B-cell lymphomas (DLBCLs) are a heterogeneous group of such GC-derived tumors. Based on their gene expression profile, DLBCLs can be divided into activated B-cell-like and GC-like subgroups. The human gene HGAL is predominantly expressed in GCs. It is also part of the gene expression signature of GC-like DLBCL, and its high expression in DLBCL has been associated with a better clinical prognosis. We have generated mice deficient of the HGAL homologue M17 in order to investigate its functional significance. The mutant animals form normal GCs, undergo efficient CSR and SHM, and mount T-cell-dependent antibody responses similar to wild-type controls. Thus, M17 is dispensable for the GC reaction, and its potential function in the pathogenesis of DLBCL remains elusive.

Animals↗