Tumor metastasis is the primary cause of mortality in patients with cancer. Several chemokines are identified as important mediators of tumor growth and/or metastasis. The level of CXCL13 has been reported to be elevated in serum or tumor tissues in patients, which mainly functions to attract B cells and follicular B helper T cells. However, the role of CXCL13 in cancer growth and metastasis is not fully explored. In the current study, we found that CXCL13 is not a strong mediator to directly promote tumor growth; however, the mice deficient in CXCL13 had far fewer pulmonary metastatic foci than did the wild-type mice in experimental pulmonary metastatic models. In addition, Cxcl13^−/− mice also had fewer IL-10–producing B cells (CD45⁺CD19⁺IL-10⁺) in the metastatic tumor immune microenvironment than those of wild-type C57BL/6 mice, resulting in an enhanced antitumor immunity. Notably, CXCL13 deficiency further improved the efficacy of a traditional chemotherapeutic drug (cyclophosphamide), as well as that of anti–programmed death receptor-1 immunotherapy. These results suggested that CXCL13 has an important role in regulating IL-10–producing B cells in tumor metastasis and might be a promising target for improving therapeutic efficiency and stimulating tumor immunity in future cancer therapy. Key Points CXCL13 contributes to tumor metastasis by recruiting regulatory B cells. Recruited regulatory B cells affect both innate and adaptive immunity. Lack of CXCL13 increases the efficacy of chemotherapy and PD-1 blockade.

Objective: Currently, the most commonly used methods for linkage analysis of pre‐implantation genetic testing for monogenic disorders (PGT‐M) are next generation sequencing (NGS) and SNP array. We aim to investigate whether the application efficacy of Asian screening array (ASA) in PGT‐M preclinical workup for the Chinese population is superior to NGS based single nucleotide polymorphism (SNP) panels.Methods: We conducted a retrospective analysis by reviewing 294 couples from a single center over the past 4 years and compared the detection results between NGS‐based SNP panels and ASA. Using the numbers of informative SNPs upstream and downstream flanking of variants, we assessed the detection efficiency of both methods in monogenic diseases, chromosomal microdeletion syndrome and males with de novo variants, among other scenarios.Results: Results indicate that ASA offers a greater number of informative SNPs compared with NGS‐based SNP panels. Additionally, data analysis for ASA is generally more straightforward and may require less computational resources. While ASA can address most PGT‐M challenges, we have also identified certain genes in previous tests that are not suitable for PGT‐M using ASA.Conclusion: The application of ASA in PGT‐M preclinical workup for Chinese populations has good practical value as it can perform linkage analysis for most genetic variants. However, for certain variants, NGS or other testing methods, such as mutated allele revealed by sequencing with aneuploidy and linkage analysis (MARSALA), may still be necessary for completion.

Introduction: X-linked recessive chronic granulomatous disease (XR-CGD) is a severe primary immunodeficiency principally caused by a CYBB (OMIM: 300481) gene variant. Recurrent fatal bacterial or fungal infections are the main clinical manifestations of XR-CGD. Patient concerns: In the current case, in vitro fertilization (IVF) associated with preimplantation genetic testing for monogenic disorder (PGT-M) was applied for a Chinese couple who had given birth to a boy with XR-CGD. Diagnosis: Next-generation sequencing-based SNP haplotyping and Sanger-sequencing were used to detect the CYBB gene variant (c.804 + 2T>C, splicing) in this family. Interventions: The patient was treated with IVF and PGT-M successively. Outcomes: In this IVF cycle, 7 embryos were obtained, and 2 of them were euploid and lacked the CYBB gene variant (c.804 + 2T>C). The PGT results were verified by prenatal diagnosis after successful pregnancy, and a healthy girl was eventually born. Conclusion: PGT-M is an effective method for helping families with these fatal and rare inherited diseases to have healthy offspring. It can availably block the transmission of disease-causing loci to descendant.

Balanced chromosomal rearrangements (BCRs) refer to a type of chromosomal structural variations without chromosomal gains or losses. BCR carriers may experience fertility issues, including a higher risk of infertility, recurrent miscarriages, or having offspring with chromosomal abnormalities. Since there are no apparent gains or losses of genetic materials in BCR carriers, their detection has long been a focal and challenging issue in the field of chromosomal structural variation analysis. Karyotyping cannot detect submicroscopic rearrangements because of restricted resolution and the application of fluorescence in situ hybridization (FISH) is limited by the necessity of a known loci. Chromosomal microarray analysis and standard short-read sequencing, widely used in clinical practice, cannot detect BCRs. In summary, the clinical detection techniques are unable to accurately identify the breakpoints of BCRs. The improved short-read sequencing such as mate-pair sequencing has been found to detect balanced rearrangements. Emerging advanced technologies such as long-read sequencing, and optical genome mapping, have already shown their potential in detecting BCRs. This review primarily elucidates the principles, applicability, advantages, and limitations of the detection techniques for BCRs, aiming to assist in the early identification and appropriate advice of patients with BCRs in genetic counseling.