BACKGROUND: B-cell maturation antigen (BCMA)-directed chimeric antigen receptor T (CAR-T) therapy yield remarkable responses in patients with relapsed/refractory multiple myeloma (R/RMM). Circulating tumor DNA (ctDNA) reportedly exhibits distinct advantages in addressing the challenges posed by tumor heterogeneity in the distribution and genetic variations in R/RMM. METHODS: Herein, the ctDNA of 108 peripheral blood plasma samples from patients with R/RMM was thoroughly investigated before administration of anti-BCMA CAR-T therapy to establish its predictive potential. Flow cytometry is used primarily to detect subgroups of T cells or CAR-T cells. RESULTS: In this study, several tumor and T cell effector-mediated factors were considered to be related to treatment failure by an integrat analysis, including higher percentages of multiple myeloma (MM) cells in the bone marrow (P = 0.013), lower percentages of CAR-T cells in the peripheral blood at peak (P = 0.037), and higher percentages of CD8+ T cells (P = 0.034). Furthermore, there is a substantial correlation between high ctDNA level (>143 ng/mL) and shorter progression-free survival (PFS) (P = 0.007). Multivariate Cox regression analysis showed that high levels of ctDNA (>143 ng/mL), MM-driven high-risk mutations (including IGLL5 [P = 0.004], IRF4 [P = 0.024], and CREBBP [P = 0.041]), number of multisite mutations, and resistance-related mutation (ERBB4, P = 0.040) were independent risk factors for PFS. CONCLUSION: Finally, a ctDNA-based risk model was built based on the above independent risk factors, which serves as an adjunct non-invasive measure of substantial tumor burden and a prognostic genetic feature that can assist in predicting the response to anti-BCMA CAR-T therapy. REGISTERATION Chinese Clinical Trial Registry (ChiCTR2100046474) and National Clinical Trial (NCT04670055, NCT05430945).

Urate oxidase (Uox) plays a pivotal role in uric acid (UA) degradation, and it has been applied in controlling serum UA level in clinical treatment of hyperuricemia (HUA). However, because Uox is a heterogenous protein to the human body, the immune rejections typically occur after intravenous administration, which greatly hampers the application of Uox-based agents. In this study, we used Lactococcus lactis NZ9000, a food-grade bacterium, as a host to express exogenous Uox genes, to generate the Uox-expressing engineered strains to treat HUA. Aspergillus flavus-derived Uox (aUox) and the "resurrected" human-derived Uox (hUox) were cloned into vector and expressed in NZ9000, to generate engineered strains, respectively. The engineered NZ9000 strains were confirmed to express Uox and showed UA-lowering activity in a time-dependent manner in vitro. Next, in an HUA mice model established by oral gavage of yeast paste, the UA levels were increased by 85.4% and 106.2% at day 7 and day 14. By contrast, in mice fed with NZ9000-aUox, the UA levels were increased by 39.5% and 48.3% while in mice fed with NZ9000-hUox were increased by 57.0% and 82.9%, suggesting a UA-lowering activity of both engineered strains. Furthermore, compared with allopurinol, the first-line agent for HUA treatment, mice fed with NZ9000-aUox exhibited comparable liver safety but better kidney safety than allopurinol, indicating that the use of engineered NZ9000 strains not only alleviated kidney injury caused by HUA, but could also avoided the risk of kidney injury elicited by using allopurinol. Collectively, our study offers an effective and safe therapeutic approach for HUA long-term treatment and controlling.
Animals ; Lactococcus lactis/metabolism* ; Urate Oxidase/genetics* ; Mice ; Uric Acid/blood* ; Hyperuricemia ; Humans ; Administration, Oral ; Aspergillus flavus/genetics* ; Male

HuR (human antigen R), an mRNA-binding protein responsible for poor prognosis in nearly all kinds of malignancies, is a potential anti-tumor target for drug development. While screening HuR inhibitors with a fluorescence polarization (FP) based high-throughput screening (HTS) system, the clinically used drug eltrombopag was identified. Activity of eltrombopag on molecular level was verified with FP, electrophoretic mobility shift assay (EMSA), simulation docking and surface plasmon resonance (SPR). Further, we showed that eltrombopag inhibited cell proliferation of multiple cancer cell lines and macrophages, and the anti-tumor activity was also demonstrated in a 4T1 tumor-bearing mouse model. The data showed that eltrombopag was efficient in reducing microvessels in tumor tissues. We then confirmed the HuR-dependent anti-angiogenesis effect of eltrombopag in 4T1 cells and RAW264.7 macrophages with qRT-PCR, HuR-overexpression and HuR-silencing assays, RNA stability assays, RNA immunoprecipitation and luciferase assays. Finally, we analyzed the anti-angiogenesis effect of eltrombopag on human umbilical vein endothelial cells (HUVECs) mediated by macrophages with cell scratch assay and Matrigel angiogenesis assay. With these data, we revealed the HuR-dependent anti-angiogenesis effect of eltrombopag in breast tumor, suggesting that the existing drug eltrombopag may be used as an anti-cancer drug.

OBJECTIVETo explore the differences in sensitivity to rapamycin of five esophageal squamous cell carcinoma cell lines with different differentiation and the changes of sensitivity of the cells after siRNA-interfered expression of p70S6K.

METHODSEffects of rapamycin on proliferation of ESCC cell lines with different differentiation, EC9706, TE-1, Eca109, KYSE790 and KYSE450 cells, were investigated using cell counting kit 8 (CCK-8) assay, and according to the above results, the EC9706 cells non-sensitive to rapamycin were chosen to be transfected with p70S6K-siRNA. The changes in sensitivity of cells to rapamycin were measured in vitro and in vivo using CCK-8 kit, flow cytometry and tumor formation in nude mice.

RESULTSCCK-8 results showed that all the five cell line cells were sensitive to low concentration of rapamycin (<100 nmol/L), but TE-1 and EC9706 cells, which were with poor differentiation, showed resistance to high concentration of rapamycin. After EC9706 cells were treated with 50, 100, 200, 500 and 1 000 nmol/L rapamycin and p70S6K-siRNA, the proliferation rates of EC9706 cells were (48.67 ± 1.68)%, (15.45 ± 1.54)%, (14.00 ± 0.91)%, (10.97 ± 0.72)% and (2.70 ± 0.32)%, respectively, and were significantly lower than that of cells treated with 50, 100, 200, 500 and 1 000 nmol/L rapamycin and control siRNA [(74.53 ± 1.71)%, (68.27 ± 1.35)%, (71.74 ± 2.44)%, (76.23 ± 1.02)% and (80.21 ± 2.77)%] (P<0.05 for all). The results of flow cytometry showed that the ratios of cells in G1 phase of the p70S6K-siRNA, rapamycin and p70S6K-siRNA+ rapamycin groups were (53.82 ± 1.78)%, (57.87 ± 4.01)% and (73.73 ± 3.68)%, respectively, significantly higher than that in the control group (46.09 ± 2.31)% (P<0.05 for all). The results of tumor formation test in vivo showed that the inhibitory effect of rapamycin on tumor growth was stronger after the cells were transfected with p70S6K-siRNA, and the inhibition rate was 96.5%.

CONCLUSIONESCC cells with different differentiation have different sensitivity to rapamycin, and p70S6K-siRNA can improve the sensitivity of cells to rapamycin in vitro and in vivo.

Animals ; Antibiotics, Antineoplastic ; pharmacology ; Carcinoma, Squamous Cell ; drug therapy ; metabolism ; pathology ; Cell Differentiation ; Cell Line, Tumor ; Cell Proliferation ; Esophageal Neoplasms ; drug therapy ; metabolism ; pathology ; Humans ; Mice ; Mice, Nude ; RNA, Small Interfering ; Ribosomal Protein S6 Kinases, 70-kDa ; genetics ; metabolism ; Signal Transduction ; Sirolimus ; pharmacology ; Transfection