BACKGROUND: Several studies have demonstrated the occurrence of secondary tumors as a rare but significant complication of chimeric antigen receptor T (CAR-T) cell therapy, underscoring the need for a detailed investigation. Given the limited variety of secondary tumor types reported to date, a comprehensive characterization of the various secondary tumors arising after CAR-T therapy is essential to understand the associated risks and to define the role of the immune microenvironment in malignant transformation. This study aims to characterize the immune microenvironment of a newly identified secondary tumor post-CAR-T therapy, to clarify its pathogenesis and potential therapeutic targets. METHODS: In this study, the bone marrow (BM) samples were collected by aspiration from the primary and secondary tumors before and after CD19 CAR-T treatment. The CD45 + BM cells were enriched with human CD45 microbeads. The CD45 + cells were then sent for 10× genomics single-cell RNA sequencing (scRNA-seq) to identify cell populations. The Cell Ranger pipeline and CellChat were used for detailed analysis. RESULTS: In this study, a rare type of secondary chronic myelomonocytic leukemia (CMML) were reported in a patient with diffuse large B-cell lymphoma (DLBCL) who had previously received CD19 CAR-T therapy. The scRNA-seq analysis revealed increased inflammatory cytokines, chemokines, and an immunosuppressive state of monocytes/macrophages, which may impair cytotoxic activity in both T and natural killer (NK) cells in secondary CMML before treatment. In contrast, their cytotoxicity was restored in secondary CMML after treatment. CONCLUSIONS This finding delineates a previously unrecognized type of secondary tumor, CMML, after CAR-T therapy and provide a framework for defining the immune microenvironment of secondary tumor occurrence after CAR-T therapy. In addition, the results provide a rationale for targeting macrophages to improve treatment strategies for CMML treatment.
Humans ; Lymphoma, Large B-Cell, Diffuse/therapy* ; Tumor Microenvironment/genetics* ; Antigens, CD19/metabolism* ; Leukemia, Myelomonocytic, Chronic/genetics* ; Immunotherapy, Adoptive/adverse effects* ; Male ; Single-Cell Analysis/methods* ; Female ; Sequence Analysis, RNA/methods* ; Receptors, Chimeric Antigen ; Middle Aged

Lipophosphatidic acid(LTA)was used to stimulate Mac-T cells,and the expression lev-els and phosphorylation levels of key proteins of nuclear factor-κB(NF-κB)and mitogen-activated protein kinase(MAPK)signaling pathway and the expression levels of upstream key action factors TLR4 and MyD88 proteins were detected by Western blot,and EDU assay was used to detect cell proliferation levels and flow cytometry was used to detect apoptosis.The results showed that acti-vation of GPR120 significantly decreased the phosphorylation levels of LTA-induced NF-κB(P65 and IκBα)(P＜0.01)and MAPK(JNK,ERK,p38)(P＜0.01)in Mac-T cells;inhibition of GPR120 was able to upregulate LTA-induced NF-κB(p65 and IκBα)in Mac-T cells(P＜0.01)and MAPK(JNK,ERK,p38)phosphorylation levels(P＜0.01);and activation of GPR120 significantly allevia-ted LTA-induced upregulation of TLR4 and MyD88(P＜0.01);inhibition of GPR120 significantly exacerbated LTA-induced upregulation of TLR4 and MyD88(P＜0.05);LTA stimulation led to a trend of diminished Mac-T cell proliferation and significantly increased apoptosis,whereas activa-tion of the GPR120 gene significantly increased cell activity(P＜0.01),promoted cell proliferation and significantly reduced apoptosis(P＜0.05)thereby alleviating the damage to Mac-T cells by LTA;LTA stimulation led to a highly significant increase in apoptosis(P＜0.01).In contrast,acti-vation of the GPR120 gene significantly reversed the increase in the apoptosis rate of Mac-T cells induced by LTA(P＜0.01),while inhibition of the GPR120 gene enhanced the apoptosis-promo-ting effect of LTA(P＜0.05),indicating that activation of the GPR120 gene attenuated the in-crease of apoptosis rate caused by LTA-induced inflammatory Mac-T cells.The results suggest that GPR120 can regulate inflammation by mediating TLR4 and MyD88 expression to inhibit NF-κB/MAPK inflammatory pathway activation and can promote cell proliferation.

Objective:To evaluate the risk factors of clinical cure and biochemical recurrence (BCR) after radical prostatectomy (RP).Methods:The clinical data of 896 patients who underwent RP at Peking University First Hospital from April 2001 to December 2020 were retrospectively analyzed. Average age was (65.90±6.3) years, median preoperative prostate specific antigen (PSA) was 10.75 (0.36-264.20) ng/ml, median prostate volume was 40.0 (12.0-220.9) ml, median PSA density (PSAD) was 0.27 (0.02-3.42) ng/(ml·g). Clinical staging: 432 cases in T 1c stage, 333 cases in T 2a/bstage, 76 cases in T 2c stage, and 55 cases in ≥T 3 stage. Preoperative Gleason score of biopsy: 193 cases in 3+ 3, 315 cases in 3+ 4, 162 cases in 4+ 3, 226 cases in ≥8. The RP surgery was operated by open or laparoscopic or robot-assisted approach. Clinical cure and BCR were used as the end points for analysis. Clinical cure was defined as a decrease in serum PSA level below 0.03 ng/ml 6 weeks after surgery. BCR was defined as the 2 consecutive serum PSA >0.2ng/ml during the follow-up after RP. Multivariate logistic regression was used to analyze the independent risk factors of clinical cure. The Kaplan-Meier method was used to draw the biochemical recurrence-free survival curve, the log-rank method was used for univariate analysis of BCR, and the Cox regression analysis was used for multivariate analysis. Results:All 896 patients were followed-up for 58 (5-241) months, 678 cases (75.7%) achieved clinical cure. Based on univariate analysis and multivariate analysis, among the preoperative indicators, whether the proportion of positive biopsy needles ≥33% ( P=0.007) and preoperative Gleason score of biopsy ( P=0.041) were independent risk factors of clinical cure. A total of 890 cases were included in the analysis of risk factors of BCR, of whom 172 cases (19.3%) had BCR. The 1-, 5-, and 10-year biochemical recurrence-free survival(BFS)rates were 98.1%, 83.1% and 68.4% respectively. The median BFS has not been reached, and the average BFS was 181 months (95% CI 172-189). The results of univariate and multivariate analysis showed that whether achieved clinical cure ( P=0.001) and postoperative pathological staging ( P<0.001) were independent risk factors of BCR. Conclusions:Whether the proportion of positive biopsy needles≥33% and preoperative Gleason score of biopsy were independent risk factors of clinical cure. Postoperative pathological staging and whether achieved clinical cure may be independent risk factors of BCR.

Objective:To clone and express the HCDH gene fragment in E.coli,and then to prepare its antiserum.Methods:The HCDH gene fragment was amplified by PCR,and ligated to the expression vector pMAL-P2X after DNA sequencing analysis.Recombinant plasmid was transformed into the E.coli.Then its expression was induced by IPTG and analyzed by SDS-PAGE.The otter rabbit was immunized with maltose resin affinity purified antigen.Antiserum valence was detected using ELISA and AGP test.The specificity was detected using Western blot.Results:The objective products of 786 bp were obtained,then the prokaryotic expression vector of HCDH gene was established and the corresponding antiserum was prepared successfully.Conclusion:It lays solid foundation for the further researches on detecting the changes of HCDH protein on the expression level or the expression regulation of HCDH gene.