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2508 citation(s) found for "Yu, Yang".

STAG2 mutations regulate 3D genome organization, chromatin loops, and Polycomb signaling in glioblastoma multiforme
Waldman, Todd , Kim, Jun‐Sik , Xu, Wanying , Yang, Tianyi , Ya, Alvin , Tallon, Luke J. , Sadzewicz, Lisa , Harris, Brent T. , Sarkaria, Jann N. , Sarkaria, Jann N , Kim, Jun-Sik, Xu, Wanying, Jin, Fulai

No container title available | December 1, 2023 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-3673198/v1 Get It

Abstract Inactivating mutations of genes encoding the cohesin complex are common in a wide range of human cancers. STAG2 is the most commonly mutated cohesin complex subunit. Here we report the impact of stable correction of endogenous, naturally occurring STAG2 mutations on gene expression, 3D genome organization, chromatin loops, and Polycomb signaling in glioblastoma multiforme (GBM). In two GBM cell lines, correction of their STAG2 mutations significantly altered the expression of ~10% of all expressed genes. Virtually all the most highly regulated genes were negatively regulated by STAG2 (i.e., expressed higher in STAG2-mutant cells than in STAG2-corrected cells), and one of them – HEPH – was regulated by STAG2 in uncultured GBM tumors as well. While STAG2 correction had little effect on large scale features of 3D genome organization (A/B compartments, TADs), STAG2 correction did alter thousands of individual chromatin loops, some of which controlled the expression of adjacent genes. Loops specific to STAG2-mutant cells, which were regulated by STAG1-containing cohesin complexes, were very large, supporting prior findings that STAG1-containing cohesin complexes have greater loop extrusion processivity than STAG2-containing cohesin complexes and suggesting that long loops may be a general feature of STAG2-mutant cancers. Finally, STAG2-regulated chromatin loops were enriched for the H3K27me3 Polycomb epigenetic mark, revealing that inactivation of STAG2 can activate Polycomb signaling in GBM, identifying a potential target for therapeutic intervention in STAG2-mutant tumors. Together, these findings illuminate the landscape of STAG2-regulated genes, A/B compartments, chromatin loops, and pathways in GBM, providing important clues into the largely still unknown mechanism of STAG2 tumor suppression.
IRF4 Expression in Germinal Center and Lymphoma B Cells Regulates Antigen-Dependent Immune Response
Mukherjee, Prithviraj , Dasari, Surendra , Hachfeld, Christine, Tang, Xinyi , Weivoda, Megan , Ansell, Stephen M. , Mondello, Patrizia , Nelson, Geoffrey M. , Bhardwaj, Vaishali , Yang, Zhi-Zhang , Wang, Zhiquan , Shlomchik, Mark , Pasqualucci, Laura , Adelman, Karen

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 4142-4142

10.1182/blood-2023-174580 Get It

A substantial subset of follicular lymphoma (FL) patients has an early relapse with a poor outcome. We showed that this unfavorable group displays increased expression of IRF4, dysregulated immune signaling and an immunosuppressive microenvironment. At the molecular level, IRF4 controls expression of antigen presentation and immune molecules (e.g. HLA-DR, CD40, PDL1). Furthermore, silencing of IRF4 triggers anti-lymphoma immunity ( Mondello P et al, Blood 2022;140 Suppl 1:168-169). However, little is known on the molecular mechanisms whereby IRF4 controls the crosstalk between B and T cells. To address this question, first we performed RNA-seq, ATAC-seq and CUT&TAG of active (H3K27Ac, H3K4me3) and repressive (H3K27me3, H3K4me1) histone marks in TMD8 and HBL1 (lymphoma cells with high IRF4 expression) transfected with two pairs of siIRF4 or siCtr for 72 hours. Gene expression revealed a broad change in transcription, with 432 upregulated genes and 136 downregulated genes in siIRF4 compared to siCtr. Notably, the genes with increased expression following IRF4 silencing coded for antigen presentation, immune molecules and cytokines (e.g. HLA-DR, CD86, IL6, IL10). Accordingly, we observed significant enrichment of antigen presentation, interferon and immune response signatures ( Fig 1A). Integrating RNA-seq with chromatin accessibility showed a significant shift towards transcriptional upregulation at genes nearest to upregulated ATAC peaks, with significant enrichment at enhancers (n=771). Conversely, transcriptional suppression was enriched at enhancers (n=2,458) of downregulated peaks. k-means analyses of all union peaks, generated by merging ATAC with CUT&TAG peaks, revealed a significant gain of H3K4me3, with concordant loss of H3K4me1 at enhancers with upregulated gene expression. In contrast, H3K4me3 was severely decreased at suppressed peaks. TF motif analysis revealed an enrichment for PU.1 and E2A at IRF4-bound regions, suggesting their cooperation in regulating immune signaling. Since antigen presentation and other immune molecules are critical components of the immune synapse, we explored the role of IRF4 on the interaction between germinal center (GC) B and T cells by crossing irf4 fl/fl mice with conditional deletion of irf4 ( Klein et al, Nat Immunol 2006) and Cγ 1cre mice ( Cγ 1cre; irf4 fl/fl) to induce recombination in GC B cells. After 10 days of immunization (GC reaction peak), Cγ 1cre; irf4 fl/fl and Cγ 1cre; irf4 fl/+ GC B cells showed significant increase of HLA-DR and CD40 expression compared to WT. As expected, Cγ 1cre; irf4 fl/fl mice displayed a significantly skewed light-zone:dark-zone ratio in favor of increased dark-zone, which are the cells that most reflect the action of BCL6, with concordant suppression of plasma cells. Additionally, we observed a significant increase of CD4 + T cells after partial or complete deletion of irf4, with upregulation of T FH cells and decrease of T reg cells ( Fig 1B). Notably, mice with loss of irf4 showed a significant decrease in exhausted T FH cells. To test if this effect was dependent on MHC:TCR interaction, we cocultured CD4 + T cells with TMD8 cells transfected with two siIRF4 or siCtr in presence of blocking antibodies for MHC class I, MHC class II or both. Blocking one or the other MHC class I or II partially rescued the IRF4 effect on T reg and T FH cells respectively as well as reduced anti-lymphoma cytotoxicity. Further experiments blocking IRF4-dependent IL6 and IL10 identified these two cytokines as responsible for the additional effects on T cells. To confirm this as an antigen-dependent immune response we coculture sorted GC B cells from NP-OVA-immunized Cγ 1cre; irf4 fl/fl, Cγ 1cre; irf4 fl/+ and WT mice with CSFE-labeled OVA-specific OT-II CD4 + T cells at a ratio of 2:1 in an organoid system for 5 days. We observed induced antigen specific proliferation of CD4 + T cells in the presence of Cγ 1cre; irf4 fl/fl and Cγ 1cre; irf4 fl/+ GC B cellscompared to WT,as indicated by decrease in CSFE expression . We confirmed an increase of T FH cells and a decrease of T reg cells, supporting the conclusion that IRF4 directly controls the antigen-dependent immune response . In summary, IRF4 expression in GC and lymphoma B cells regulates immune signaling with PU.1 and E2A, thereby modulating antigen-dependent immune responses with potential implications for lymphomagenesis. Future studies investigating targeting of IRF4 in lymphoma are warranted.
Paired Circulating Tumor DNA in Cerebrospinal Fluid and Peripheral Blood: Reliable Technology for Diagnosing and Monitoring Primary and Secondary Central Nervous Lymphoma
Xiu, Bing, Liang, Aibin , Zhu, Xinyu , Zhu, Jingjing , Yang, Zhi-Zhang

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 2994-2994

10.1182/blood-2023-189100 Get It

Objective: This research delineates the temporal alterations of cell-free circulating tumor DNA (ctDNA) in the plasma and cerebrospinal fluid (CSF) of patients harboring primary and secondary central nervous system (CNS) lymphoma. The aim is to establish that CSF serves as a superior reservoir of ctDNA compared to plasma, thereby aiding in diagnostic processes and monitoring therapeutic efficacy. Concurrently, this study underscores the enhanced response and survival rates in patients administered Bruton's tyrosine kinase (BTK) inhibitors over an extended period exceeding three months. Methods: Data including cranial-enhanced magnetic resonance imaging (MRI) scans, leukocyte and protein concentrations in the CSF, exfoliated CSF cytology, flow cytometry, interleukin-10 to interleukin-6 ratios, ctDNA in plasma and CSF, were gathered from patients presenting primary and secondary CNS lymphoma(7 PCNSL,9 SCNSL). The temporal ctDNA modifications in plasma and CSF during the patient's disease progression-initial onset, remission, and relapse-were scrutinized. Additionally, the implications of BTK inhibitor usage on patient response rates and survival rates were assessed. Results: Within the cohort of primary CNS lymphoma patients, ctDNA was detected in the CSF and plasma of 2 and 5 patients, respectively. Conversely, in patients with secondary CNS lymphoma, CSF and plasma ctDNA were discovered in 8 and 4 cases, respectively. The detection rate was contingent upon the central lesion's magnitude and position and the patient's surgical history related to the brain. Four patients, including two from each group, underwent cranial-enhanced MRI to appraise tumor burden at various disease stages, simultaneously with the monitoring of ctDNA in plasma and CSF. It was revealed that ctDNA levels in the CSF were in synchrony with the tumor burden, whereas plasma ctDNA levels remained relatively static. This indicates that CSF ctDNA may serve as a viable tool to assess therapeutic responses in CNS lymphoma patients. In two patients where surgical biopsy was unfeasible and both CSF exfoliation cytology and flow cytometry returned negative results, CSF ctDNA was positive, thereby underscoring its auxiliary role in diagnosing CNS lymphoma. Furthermore, the study indicated improved response and survival rates in patients subjected to BTK inhibitors for over three months. Conclusion: CSF ctDNA demonstrates potential in detecting CNS lymphoma and in the dynamic monitoring of therapeutic responses. Compared to cranial-enhanced MRI, exfoliated CSF cytology, and flow cytometry, CSF ctDNA testing offers superior sensitivity. For patients for whom brain surgical biopsy is not an option, CSF ctDNA testing emerges as a valuable supplementary diagnostic tool. CSF ctDNA allows for dynamic monitoring of therapeutic responses in CNS lymphoma patients, enabling the detection of residual lesions, and thereby guiding the formulation and duration of the treatment regimen. Patients administered oral BTK inhibitors for more than three months demonstrate higher treatment response and survival rates.
Number Needed to Treat Analyses of Zanubrutinib in Relapsed/Refractory Chronic Lymphocytic Leukaemia
Chanan‐Khan, Asher , Xue, Mei , Massoudi, Marjan , Balk, Mark, ZivariPiran, Hossein, Duan, Cecilia, Yang, Keri, Hanna, Kirollos S.

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 2337-2337

10.1182/blood-2023-174709 Get It

Introduction: Chronic lymphocytic leukaemia (CLL) is the most common leukaemia type. In 2020, there were an estimated 207,463 people living with CLL, with an annual incidence of approximately 4.9 per 100,000 in the United States (US). Zanubrutinib is a Bruton tyrosine kinase inhibitor that is FDA-approved and an NCCN preferred and recommended treatment of CLL. In the phase 3 ALPINE trial (NCT03734016), zanubrutinib elicited a significantly higher overall response rate and significantly longer progression-free survival (PFS) than ibrutinib. This study aimed to compare zanubrutinib versus ibrutinib in Relapsed/Refractory (R/R) CLL by calculating the number needed to treat (NNT) to avoid one progression or death and associated incremental costs. Methods:A health-economic model was developed to evaluate the number of R/R CLL patients needed to be treated to avoid a progression or death from the US payer perspective. Payer blend was assumed with 40% Commercial and 60% Medicare payer mix. Clinical efficacy data were extracted from the ALPINE trial. Final analysis result of 24-month PFS (79.5% for zanubrutinib and 67.3% for ibrutinib) was used for the base-case analysis in the model. Treatment, adverse event management, other medical resource use, and subsequent treatment costs were considered in the model. The NNT, incremental cost per treated patient, and incremental cost per additional patient with progression or death were captured. Deterministic sensitivity analyses were conducted to assess parameter uncertainties and explore key model drivers. Scenario analyses were conducted to test the impact of different PFS estimates. Results: The base-case results fromthe NNT model showed that for every 8 patients treated with zanubrutinib, 1 event of progression or death would be avoided compared to using ibrutinib. The total costs per patient treated with zanubrutinib and ibrutinib are $370,558 and $430,150, respectively, with a cost savings of $59,593 associated with using zanubrutinib (Table). Drug costs and PFS have the greatest impact on the incremental cost per patient. Varying the PFS scenarios, including adjustment with drug interruption, COVID death, or treatment discontinuation, change the NNT from 8 to 12, and are associated with cost savings of $58,179 to $67,153 per zanubrutinib-treated patient in a 24-month time frame. Applying the model result to a hypothetical scenario of a clinical practice of 100 patients treated with zanubrutinib versus ibrutinib suggest that approximately 13 patients will avoid disease progression events or death. Conclusions: The NNT model suggests thatusing zanubrutinib to treat R/R CLL patients, compared to ibrutinib, will result in more favorable clinical and economic outcomes in the US.
Impact of Real-World Treatment Sequencing Patterns on Time to Next Treatment among Patients with Chronic Lymphocytic Leukemia in the United States
Chanan‐Khan, Asher , Challagulla, Swetha, Kaushiva, Alpana, Miller, Vincent A. , Wang, Yuexi , Yang, Keri, Smith, Helen

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 5143-5143

10.1182/blood-2023-179536 Get It

Background: The treatment landscape for chronic lymphocytic leukemia (CLL) is evolving at a rapid pace, with development of several targeted therapies. The real-world applicability of clinical trial effectiveness is markedly influenced by treatment choices, the specific characteristics of patients' diseases, their overall health, and individual preferences. However, there is limited evidence to understand the impact of multiple treatment options on real-world effectiveness in CLL in routine clinical practice. This study aimed to characterize recent real-world treatment sequencing patterns and associated time to next treatment among patients with CLL in the United States. Methods: This retrospective observational study included patients diagnosed with CLL (≥18 years at diagnosis) from January 1, 2018, through January 1, 2023, who received ≥1 treatment after initial diagnosis. Patients were sourced from the ConcertAI RWD360 dataset, a real-world de-identified dataset >6 million patients from across the United States derived from various electronic health record systems and integrated with a large administrative open claims dataset. Patients were followed through the end of the record or death, whichever occurred first. Patients were classified into the following treatment categories: chemotherapy (including bendamustine-based and other chemotherapy), anti-CD20-based, Bruton tyrosine kinase inhibitor (BTKi)-based (ibrutinib, acalabrutinib, or zanubrutinib), and venetoclax-based therapy. Demographic and clinical characteristics, treatment sequencing pattern, and time to next treatment were examined across lines of therapy for each treatment category. Kaplan-Meier analysis was used to estimate median time to next treatment. Results: The study included 3,431 patients with CLL (median age: 69 years; male: 63.8%). There was a significant variation in average age among the 4 treatment groups ( P<0.0001). Compared with the overall population, patients who received anti-CD20-based therapy were slightly older (median age: 71 years), while patients who received venetoclax-based therapy were relatively younger (median age: 67 years). Patients were primarily treated in community rather than academic settings (76.4% vs 21.3%). First-line patients were most commonly treated with BTKi (60.1%), venetoclax (16.0%), and anti-CD20 (15.4%) regimens. Among patients who initiated BTKi therapies, zanubrutinib use (2.6%) was limited; this may be due to the recent approval date (January 2023). Among CLL patients, 35.0% received second-line treatment and BTKi stayed dominant (35.7%), followed by anti-CD20 (29.6%) and venetoclax (25.8%) therapies. From first- to second-line therapy, the prevailing sequencing pattern was from either one BTKi to another BTKi (23.5%), venetoclax to anti-CD20 (13.2%), or BTKi to an anti-CD20 (9.7%). From second- to third-line therapy, patients most frequently switched from anti-CD20 to venetoclax (24.6%), anti-CD20 to BTKi (13.3%), or one BTKi to another BTKi (12.6%). From third- to fourth-line therapy, the predominant sequencing pattern was from venetoclax to anti-CD20 (21.3%), anti-CD20 back to venetoclax (20.6%), or one BTKi to another BTKi (11.6%). Median time to next treatment in first line was significantly longest for patients receiving BTKi (53.9 months) and shortest for patients treated with venetoclax (7.7 months) ( P<0.0001) (Figure 1). Median time to next treatment in second line was not reached among patients using BTKi, while it was significantly shorter for those on venetoclax and anti-CD20 (10.4 months and 1.5 months, respectively; P<0.0001) (Figure 2). Conclusions: This studydemonstrated unique treatment sequencing patterns among patients with CLL in the real-world setting.As the most commonly used regimen, BTKi therapy was shown to have significantly improved time to next treatment compared with other treatment regimens in first and second lines of therapies. Future studies with extended follow-up are needed to allow for assessment of newer treatments and enable evaluation of long-term clinical outcomes.
Label-free Single-molecule Immunoassay
Zhou, Xiaoyan , Chemerkouh, Mohammad Javad Haji Najafi , Snozek, Christine L.H. , Braswell, Brandyn, Wan, Zijian, Chen, Chao , Ma, Guangzhong , Yang, Eric H. , Wan, Zijian , Wang, Shaopeng

No container title available | December 1, 2023 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.26434/chemrxiv-2023-vnxgr Get It

Single-molecule immunoassay is a reliable technique for the detection and quantification of low-abundance blood biomarkers, which are essential for early disease diagnosis and biomedical research. However, current single-molecule methods all require signal amplification via labelling, which brings a variety of unwanted consequences, such as matrix effects and autofluorescence interference. Here, we introduce a real-time mass imaging-based label-free single-molecule immunoassay (LFSM-immunoassay). Featuring plasmonic scattering microscopy-based real-time mass imaging, a 2-step sandwich assay format-enabled background reduction, and minimization of matrix effects by dynamic tracking of single binding events, the LFSM-immunoassay enables ultra-sensitive and direct protein detection at the single-molecule level in neat blood sample matrices. We demonstrated that the LFSM-immunoassay can measure sub-femtomolar levels of interleukin-6 and prostate-specific antigen in whole blood with 8 log dynamic range. To show its translational potential to clinical settings, we measured NT-proBNP (N-terminal pro-brain natriuretic peptide) in 28 patient serum samples using a 20 minute LFSM-immunoassay, and the results show a strong linear correlation (r > 0.99) with clinical lab reported values.
Altered immune cell phenotypes within chronically ischemic human kidneys distal to occlusive renal artery disease
Zhu, Xiangyang , Klomjit, Nattawat , Puranik, Amrutesh S. , Lutgens, Esther , Eirin, Alfonso , Textor, Stephen C., Lerman, Lilach O. , Pawar, Aditya S. , Puranik, Amrutesh S , Lutgens, Esther , Eirin, Alfonso , Lerman, Lilach O , Klomjit, Nattawat , Yang, Zhi-Zhang , Lerman, Amir

American Journal of Physiology-Renal Physiology | November 30, 2023 | Volume: 326 | Issue: 2 | Pages: F257-F264

10.1152/ajprenal.00234.2023 | PMID 38031731 Get It

The single-cell platform mass cytometry (CyTOF) enables detection of significant changes in one million of renal cells, especially in subsets of immune cells in ischemic human kidneys distal to renal artery stenosis (RAS). We found that pro-repair cell types such as scattered tubular-progenitor-like cells, aged neutrophils, and regulatory B cells show a compensatory increase in RAS. Immune cell phenotype changes may reflect ongoing inflammation and impaired immune defense capability in the kidneys.
Results of Patch Testing to Botanicals: Review of the Mayo Clinic Experience over 2 Decades (1997–2017)
Kumar, Anagha , Jin, Mauricio F. , Kunkel, Hilary, Sathe, Nishad, Hall, Matthew R. , Drage, Lisa A., Youssef, Molly J. , Yang, Yul W. , Yiannias, James A. , Killian, Jill M. , Davis, Mark D.P. , Youssef, Molly, Killian, Jill, Kumar, Anagha Bangalore

Dermatitis® | November 27, 2023 | Volume: 35 | Issue: 1 | Pages: 43-48

10.1089/derm.2023.0109 | PMID 38011689 Get It

Abstract: Background: Botanicals are increasingly incorporated into skincare products. Although allergic contact dermatitis due to botanicals is recognized, data describing the prevalence of positive patch tests to botanicals are sparse. Objective: To report the Mayo Clinic experience of patch testing to selected botanical products in the standard, extended standard, fragrance, and plant series. Methods: IRB-approved retrospective study of the Mayo Clinic experience with patch testing to botanicals from 1997 to 2017. Results: In total, 12,169 people were patch tested to botanicals in the standard, extended standard, fragrance, and plant series; 4032 were men and 8137 were women. The mean age of the population tested was 54 (standard deviation 17.7) years. Almost 11% (1320/12,169) of the patch-tested population exhibited positive reactions to at least 1 botanical agent. Myroxylon pereirae resin 25% was the most common positive allergen in the series. Patients who had positive reactions to at least 1 botanical agent were more (19.8%) likely to have a positive reaction to at least 1 additional botanical than those patients who did not have any positive tests. Most patients presented with generalized involvement (334) or involvement of the hands (284) or face (232). Conclusion: Physicians should be aware of the high prevalence of allergic contact dermatitis and patch test positivity associated with botanical products.
Unspoken Truths
Herman, Tianna, Haines, Krista , Arora, Tania K. , Geevarghese, Sunil K. , Phillips, Joseph D. , Vicente, Diego , Griggs, Cornelia L. , Valinejad, Jaber , Alban, Andres, Swan, J. Shannon , Gazelle, G. Scott, Yang, Chi‐Fu Jeffrey , Gold, Jessica A. , Cunningham, Carrie , Collins, Reagan A. , Snyder, Rebecca A. , Stey, Anne M. , McElroy, Imani E. , Wall, Anji , Hughes, Tasha M. , Sen, Srijan , Mercaldo, Nathaniel D. , Jalali, Mohammad S. , Chhatwal, Jagpreet , Rangel, Erika, Donelan, Karen , West, Colin P.

Annals of Surgery | November 22, 2023 | Volume: 279 | Issue: 3 | Pages: 429-436

10.1097/sla.0000000000006159 | PMID 37991182 Get It

Objective: To characterize the current state of mental health within the surgical workforce in the United States. Background: Mental illness and suicide is a growing concern in the medical community; however, the current state is largely unknown. Methods: Cross-sectional survey of the academic surgery community assessing mental health, medical error, and suicidal ideation. The odds of suicidal ideation adjusting for sex, prior mental health diagnosis, and validated scales screening for depression, anxiety, post-traumatic stress disorder (PTSD), and alcohol use disorder were assessed. Results: Of 622 participating medical students, trainees, and surgeons (estimated response rate=11.4%–14.0%), 26.1% (141/539) reported a previous mental health diagnosis. In all, 15.9% (83/523) of respondents screened positive for current depression, 18.4% (98/533) for anxiety, 11.0% (56/510) for alcohol use disorder, and 17.3% (36/208) for PTSD. Medical error was associated with depression (30.7% vs. 13.3%, P<0.001), anxiety (31.6% vs. 16.2%, P=0.001), PTSD (12.8% vs. 5.6%, P=0.018), and hazardous alcohol consumption (18.7% vs. 9.7%, P=0.022). Overall, 13.2% (73/551) of respondents reported suicidal ideation in the past year and 9.6% (51/533) in the past 2 weeks. On adjusted analysis, a previous history of a mental health disorder (aOR: 1.97, 95% CI: 1.04–3.65, P=0.033) and screening positive for depression (aOR: 4.30, 95% CI: 2.21–8.29, P<0.001) or PTSD (aOR: 3.93, 95% CI: 1.61–9.44, P=0.002) were associated with increased odds of suicidal ideation over the past 12 months. Conclusions: Nearly 1 in 7 respondents reported suicidal ideation in the past year. Mental illness and suicidal ideation are significant problems among the surgical workforce in the United States.
The VUS Challenge in Cystic Kidney Disease: A Case-Based Review
Aklilu, Abinet M. , Gulati, Ashima , Kolber, Kayla J. , Yang, Hana , Dahl, Neera K. , Dahl, Neera K , Aklilu, Abinet M , Harris, Peter C.

Kidney360 | November 14, 2023 | Volume: 5 | Issue: 1 | Pages: 152-159

10.34067/kid.0000000000000298 | PMID 37962562 Get It

Genetic testing in nephrology is becoming increasingly important to diagnose patients and to provide appropriate care. This is especially true for autosomal dominant polycystic kidney disease (ADPKD) because this is a common cause of kidney failure and genetically complex. In addition to the major genes, PKD1 and PKD2 , there are at least six minor loci, and phenotypic, and in some cases, genetic overlap with other cystic disorders. Targeted next-generation sequencing, a low-cost, high-throughput technique, has made routine genetic testing viable in nephrology clinics. Appropriate pre- and post-testing genetic counseling is essential to the testing process. Carefully assessing variants is also critical, with the genetic report classifying variants in accordance with American College of Medical Genetics and Genomics guidelines. However, variant of uncertain significance (VUSs) may pose a significant challenge for the ordering clinician. In ADPKD, and particularly within PKD1 , there is high allelic heterogeneity; no single variant is present in more than 2% of families. The Mayo/Polycystic Kidney Disease Foundation variant database, a research tool, is the best current database of PKD1 and PKD2 variants containing over 2300 variants identified in individuals with polycystic kidney disease, but novel variants are often identified. In patients with a high pretest probability of ADPKD on the basis of clinical criteria, but no finding of a pathogenic (P) or likely pathogenic (LP) variant in a cystic kidney gene, additional evaluation of cystic gene VUS can be helpful. In this case-based review, we propose an algorithm for the assessment of such variants in a clinical setting and show how some can be reassigned to a diagnostic grouping. When assessing the relevance of a VUS, we consider both patient/family-specific and allele-related factors using population and variant databases and available prediction tools, as well as genetic expertise. This analysis plus further family studies can aid in making a genetic diagnosis.