Deregulated microRNAs (miRNAs) and their roles in cancer development have attracted much attention. Two miRNAs, miR-15a and miR-16, which act as putative tumor suppressor by targeting the oncogene BCL2, have been implicated in cell cycle, apoptosis and proliferation. In this study, we investigated the possible role of miR-15a/16 in the angiogenesis of multiple myeloma (MM). Using a stem-loop quantitative reverse transcription-PCR, we analyzed miR-15a/16 expressions in bone marrow samples from newly diagnosed MM patients and a panel of MM cell lines. miRNA transfection, western blotting analysis and assay of luciferase activity were used to examine whether vascular endothelial growth factor (VEGF) is the target of miR-15a/16. The functional roles of miR-15a/16 on tumorigenesis and angiogenesis were examined by in vitro angiogenesis models and in vivo tumor xenograft model. We showed that miR-15a and miR-16 were significantly underexpressed in primary MM cells as well as in MM cell lines. The aberrant expression of miR-15a/16 was detected especially in advanced stage MM. In human MM cell lines and normal plasma cells, expression of miR-15a/16 inversely correlated with the expression of VEGF-A. Western blotting combined with the luciferase reporter assay demonstrated that VEGF-A was a direct target of miR-15a/16. Ectopic overexpression of miR-15a/16 led to decreased pro-angiogenic activity of MM cells. Finally, infection of lentivirus-miR-15a or lentivirus-miR-16 resulted in significant inhibition of tumor growth and angiogenesis in nude mice. This study suggest that miR-15a/16 could play a role in the tumorigenesis of MM at least in part by modulation of angiogenesis through targeting VEGF-A.

Chimeric antigen receptor-modified T-cell (CAR-T) therapy is effective and safe for patients with relapsed/refractory B-cell acute lymphoblastic leukemia (r/r B-ALL), but its value has been limited in terms of long-term leukemia-free survival. New strategies that can help CAR-T therapy achieve lasting effect are urgently warranted. This nonrandomized interventional pragmatic clinical trial had a particular aim. It explored whether consolidative allogeneic hematopoietic stem cell transplantation (allo-HSCT) could improve the long-term prognosis of the minimal residual disease-negative complete remission (MRD − CR) patients after CAR-T therapy. In the first stage, 58 r/r B-ALL patients received split doses of CAR-T cells after lymphodepleting chemotherapy, and 51 (87.9%) achieved CR. In the second stage, 21/47 MRD − CR patients without previous allo-HSCT and contraindications or other restrictions, on their own accord, received consolidative allo-HSCT within three months after CAR-T therapy. There was no difference in overall survival (OS) between the MRD − CR patients who received allo-HSCT and those who did not. However, event-free survival (EFS) and relapse-free survival (RFS) were significantly prolonged by allo-HSCT in the subgroups. This was with either high (≥5%) pre-infusion bone marrow MRD assessed by flow cytometry (BM-FCM-MRD) or poor prognostic markers (P < .05). However, no difference was found in EFS and RFS for patients with pre-infusion BM-FCM-MRD <5% and without poor prognostic markers (P > .05). To conclude, CAR-T therapy bridging to allo-HSCT is a safe and effective therapeutic strategy for r/r B-ALL patients, and may prolong their EFS and RFS, especially when they have high pre-infusion BM-FCM-MRD or poor prognostic markers.

The CD19-targeted chimeric antigen receptor T cell (CAR-T) therapy has been widely proved effective on relapsed and refractory (r/r) B cell acute lymphoblastic leukemia (B-ALL). Meanwhile, CAR-T therapy-related toxicities, including cytokine release syndrome (CRS) and neurological toxicities, are drawing researchers' attention. In addition, our research team notices that coagulopathy and even disseminated intravascular coagulation (DIC) are common problems during CAR-T therapy. In our phase 1/2 clinical trial (NCT02965092), 53 r/r B-ALL patients underwent leukapheresis on day − 11 and received lymphodepleting chemotherapy on day − 7 to day − 5. Finally, they received split infusions of anti-CD19 CAR-T cells on day 0 to day 2. Plasma concentrations of tissue factor (TF) and platelet endothelial cell adhesion molecular-1 (PECAM-1) were also measured to identify the mechanism of coagulation disorders. The overall 1-month remission rate of the 53 patients was 88.7%. During the treatment course, 19 patients experienced grade 3-4 CRS, 8 patients developed grade 2-3 neurological toxicities. Beyond that, 30 patients (30/53, 56.6%) suffered from coagulation disorders, and half of them should be diagnosed as DIC. Benefiting from replacement and anticoagulant therapy, 14 patients successfully got out of the conditions of DIC. Remarkably, the severity of coagulopathy was positively correlated with CRS grade. What is more, plasma TF and PECAM-1 levels indicated that vascular endothelial factors played key roles in the process of CRS-related coagulopathy. To conclude, coagulation disorders frequently happen during CAR-T therapy. TF and PECAM-1 are of great importance in the etiology and pathogenesis of coagulation problems. Early and proper interventions targeted at CRS-related coagulopathy contribute a lot to the control of side effects in CAR-T therapy.

Background Myeloid-derived suppressor cells (MDSCs) and cancer stem cells (CSCs) are two important cellular components in the tumor microenvironment, which may modify the cancer phenotype and affect patient survival. However, the crosstalk between MDSCs and multiple myeloma stem cells (MMSCs) are relatively poorly understood. Methods The frequencies of granulocytic-MDSCs (G-MDSCs) in MM patients were detected by flow cytometry and their association with the disease stage and patient survival were analyzed. RT-PCR, flow cytometry, western blot and sphere formation assays were performed to investigate the effects of G-MDSCs, piRNA-823 and DNA methylation on the maintenance of stemness in MM. Then a subcutaneous tumor mouse model was constructed to analyze tumor growth and angiogenesis after G-MDSCs induction and/or piRNA-823 knockdown in MM cells. Results Our clinical dataset validated the association between high G-MDSCs levels and poor overall survival in MM patients. In addition, for the first time we showed that G-MDSCs enhanced the side population, sphere formation and expression of CSCs core genes in MM cells. Moreover, the mechanism study showed that G-MDSCs triggered piRNA-823 expression, which then promoted DNA methylation and increased the tumorigenic potential of MM cells. Furthermore, silencing of piRNA-823 in MM cells reduced the stemness of MMSCs maintained by G-MDSCs, resulting in decreased tumor burden and angiogenesis in vivo. Conclusion Altogether, these data established a cellular, molecular, and clinical network among G-MDSCs, piRNA-823, DNA methylation and CSCs core genes, suggesting a new anti-cancer strategy targeting both G-MDSCs and CSCs in MM microenvironment.

BackgroundMyeloid-derived suppressor cells (MDSCs) is a heterogeneous population of immature myeloid cells, inhibiting both the innate and adaptive immunity. Recent studies validated that MDSCs caused immune suppression and promoted cancer progression through various mechanisms. However, the prognostic value of MDSCs in cancer remains controversial.MethodsHere, we performed this meta-analysis to evaluate the prognostic value of MDSCs in various types of cancer. The electric databases, such as Pubmed, Embase and Web of Science, were searched for relevant publications. Hazards ratios (HRs) with the corresponding 95% confidence intervals (95%CIs) were calculated to evaluate the prognostic role of MDSCs in cancer.ResultsA total of 16 studies with 1864 patients were enrolled in our meta-analysis. Elevated MDSCs frequency was shown to be associated with shorter overall survival (OS) (HR = 2.46, 95%CI: 1.87–3.23), and poor disease-free survival / recurrence-free survival (DFS / RFS) (HR = 3.26, 95%CI: 2.10–5.04) after treatment. Furthermore, similar results were also observed in the stratified subgroup analysis, which included the analysis by region, sample size, cancer type, NOS scores, subtype and cut-off value of MDSCs.ConclusionHigh MDSCs might be related to poor clinical outcomes of patients with cancer, that is, MDSCs might be a potential prognostic biomarker in cancer.

Background BCMA-specific chimeric antigen receptor-T cells (CAR-Ts) have exhibited remarkable efficacy in refractory or relapsed multiple myeloma (RRMM); however, primary resistance and relapse exist with single-target immunotherapy. Bispecific CARs are proposed to mitigate these limitations. Methods We constructed a humanized bispecific BM38 CAR targeting BCMA and CD38 and tested the antimyeloma activity of BM38 CAR-Ts in vitro and in vivo. Twenty-three patients with RRMM received infusions of BM38 CAR-Ts in a phase I trial. Results BM38 CAR-Ts showed stronger in vitro cytotoxicity to heterogeneous MM cells than did T cells expressing an individual BCMA or CD38 CAR. BM38 CAR-Ts also exhibited potent antimyeloma activity in xenograft mouse models. In the phase I trial, cytokine release syndrome occurred in 20 patients (87%) and was mostly grade 1–2 (65%). Neurotoxicity was not observed. Hematologic toxicities were common, including neutropenia in 96% of the patients, leukopenia in 87%, anemia in 43% and thrombocytopenia in 61%. At a median follow-up of 9.0 months (range 0.5 to 18.5), 20 patients (87%) attained a clinical response and minimal residual disease-negativity (≤ 10–4 nucleated cells), with 12 (52%) achieving a stringent complete response. Extramedullary plasmacytoma was eliminated completely in 56% and partially in 33% and of 9 patients. The median progression-free survival was 17.2 months. Two relapsed patients maintained BCMA and CD38 expression on MM cells. Notably, BM38 CAR-Ts cells were detectable in 77.8% of evaluable patients at 9 months and 62.2% at 12 months. Conclusion Bispecific BM38 CAR-Ts were feasible, safe and significantly effective in patient with RRMM. Trial registration: Chictr.org.cn ChiCTR1800018143.

BackgroundRecent studies have emphasized the important prognostic role of long noncoding RNAs (lncRNAs) in various types of cancers. Here we conducted a meta-analysis to investigate whether lncRNA HOXA11-AS can be served as a prognostic biomarker in human cancers.Patients/methodsWe systematically searched PubMed, Embase, ISI Web of Science, and SCOPUS for relevant studies, to investigate the prognostic significance of HOXA11-AS expression in cancer patients. Odds ratios (ORs) or hazards ratios (HRs) with corresponding 95% confidence intervals (CIs) are pooled to estimate the association between HOXA11-AS expression and clinicopathological parameters or survival of cancer patients.ResultsA total of eight eligible studies with 1320 cancer patients were enrolled in our meta-analysis. The results revealed that increased expression level of HOXA11-AS was significantly associated with clinicopathological parameters including more lymph node metastasis (OR = 2.06, 95% CI 1.31–3.25), advanced tumor stage (OR = 4.22, 95% CI 2.60–6.85), as well as poor tumor differentiation (OR = 2.49, 95 CI 1.47–4.20), but not correlated with age (p = 0.101) or gender (p = 0.845). In addition, cancer patients with high HOXA11-AS are prognosed to have shorter OS (pooled HR = 1.86, 95% CI 1.39–2.48) and PFS (pooled HR = 2.47, 95% CI 1.29–4.75).ConclusionsHOXA11-AS overexpression might be a convinced unfavorable prognostic factor that helps the clinical decision-making process.

Background: Anti-B cell maturation antigen (BCMA) chimeric antigen receptor(CAR) T cell therapy has shown promising results from a series of clinical trials. But short progression-free survival (PFS) due to BCMA-negative or positive relapse is pretty much the agenda.Here we constructed a dual-target BM38 CAR incorporating the anti-CD38 and anti-BCMA single-chain variable fragment in tandem plus 4-1BB signaling and CD3 zeta domains and conducted the first-in-human clinical trial(ChiCTR1800018143) in patients with RRMM to evaluate the safety, efficacy and duration of BM38 T cells. Methods:Patients with relapsed or refractory multiple myeloma(RRMM), who had received at least 2 prior treatment regimens, including a proteasome inhibitor and an immunomodulatory agent, were enrolled in the phase 1 dose-climbing trial of the bispecific CAR-T cell therapy. Patients were subjected to a lymphodepleting regimen with Cy(250 mg/m2, d-5 to d-3) and Flu(25 mg/m2, d-5 to d-3) daily prior to the CAR-T infusion (d0). The dose gradients of infused CAR-T cells were 0.5, 1.0, 2.0, 3.0 and 4.0×106 cells/kg and at least 2 patients were involved at every dose level. The efficacy was assessed by the International Uniform Response Criteria for Multiple Myeloma (2016), and the toxicity was graded by CTCAE 5.0. Results: As of 31 July 2019, 16 pts consisting of 10(62.5%) with genetic abnormalities and 5(31.25%) with extramedullary lesions,had received BM38 CAR-T cells in the 5 dose-climbing cohorts. At a median follow-up of 36 weeks, no DLTs and no grade ≥ 3 neurotoxicities were observed. Cytokine release syndrome (CRS), mainly grade 1-2, was reported in 10 of 16 (62.5%) pts; 4 pts had grade ≥ 3 CRS that resolved by tocilizumab and supportive treatment. Almost all the pts were observed with hematological toxicities relieved in the first month after infusion.14(87.5%) pts achieved an overall response with 8(50%) sCR, 2(12.5%) VGPR and 4(25.00%) PR and 14(87.5%) reached bone marrow minimal residual disease(MRD)-negative status. The longest duration of sCR was over 51 weeks and 5(62.5%) of 8 patients had still maintained sCR and 2 transformed to VGPR and 1 to PR. The median duration of progression-free survival(PFS) had not been reached; PFS rates at 9 months was 75%. More encouragingly, 5(100%)extramedullary lesions were eliminated.Up to the observed day, the BM38 CAR-T cells still exist in the patients' peripheral blood by flow cytometry(FCM) and quantitative polymerase chain reaction(q-PCR). The peak time of CAR-T cells proliferation of sCR patients was about the 2nd week after infusion, which was earlier than other patients. 4.0 × 106 CAR T cells (pt11, 12 and 15) were selected for the optimal dose with superior response and acceptable toxicities and expansion cohort would be conducted. Conclusions:Our study demonstrates an improved efficacy with the bivalent BM38 CAR-T therapy for RRMM with a high ORR, especially a higher rate and a longer duration of sCR and effective elimination for extramedullary lesions. No neurotoxicity was observed. CRS and other toxicities were manageable. These initial data provide strong evidence to support the further development of the dual-target CAR-T therapy for RRMM. Clinical trial information: ChiCTR1800018143 Disclosures No relevant conflicts of interest to declare.