Single-cell aggrephagy-related patterns facilitate tumor microenvironment intercellular communication, influencing osteosarcoma progression and prognosis.

Osteosarcoma, a common malignant tumor in children, has emerged as a major threat to the life and health of pediatric patients. Presently, there are certain limitations in the diagnosis and treatment methods for this disease, resulting in inferior therapeutic outcomes. Therefore, it is of great importance to study its pathogenesis and explore innovative approaches to diagnosis and treatment. In this study, a non-negative matrix decomposition method was employed to conduct a comprehensive investigation and analysis of aggregated autophagy-related genes within 331,394 single-cell samples of osteosarcoma. Through this study, we have elucidated the intricate communication patterns among various cells within the tumor microenvironment. Based on the classification of aggregated autophagy-related genes, we are not only able to more accurately predict patients' prognosis but also offer robust guidance for treatment strategies. The findings of this study hold promise for breakthroughs in the diagnosis and treatment of osteosarcoma, intervention of aggrephagy is expected to improve the survival rate and quality of life of osteosarcoma patients.

Observation of Solute Transport between Articular Cartilage and Subchondral Bone in Live Mice.

OBJECTIVE: To establish a method for investigating the permeability of calcified cartilage zone (CCZ) and to observe solute transport between articular cartilage (AC) and subchondral bone (SB) through intact CCZ in vivo. DESIGN: We developed a novel fixing device combined with un-decalcified fluorescence observation method to address the permeability of CCZ in live mice. Twenty-four Balb/c female mice aged 1 to 8 months were used to observe the development of CCZ. Eighty-four Balb/c female mice (aged 1 or 6 months) with mature or immature CCZ of distal femur were used to investigate the permeability of intact CCZ in vivo. Diffusivity of rhodamine B (476 Da) and tetramethyl-rhodamine isothicyanate-dextran (TRITC-Dextran, 20 kDa) was tested from AC to SB in 0 minutes, 1 minute, 15 minutes, 30 minutes, 1 hour, and 2 hours. None diffused knee joints (0 minutes) served as blank control, while in vitro immersion of distal femurs in rhodamine B or TRITC-Dextran for 72 hours served as positive control. RESULTS: CCZ was well developed in 6-month mice. Both tracers penetrated immature CCZ down to SB in less than 1 hour in live mice, while the diffusion of both tracers decreased rapidly at tidemark in all testing time points. CONCLUSION: Current study provided direct evidence of blocking effect of CCZ in solute transportation during short diffusion period in live animal, indicating the important role of CCZ in joint development and microenvironment maintenance.

SRC3 expressed in bone marrow mesenchymal stem cells promotes the development of multiple myeloma.

SRC3 plays critical roles in various biological processes of diseases, including proliferation, apoptosis, migration, and cell cycle arrest. However, the effect of SRC3 expression in mesenchymal stem cells (MSCs) on multiple myeloma (MM) is not clear yet. In our study, MSCs (MSC-SRC3, MSC-SRC3-/-) and MM cells were co-cultured in a direct or indirect way. The proliferation of MM cells was studied by CCK-8 and colony formation assays. The apoptosis and cell cycle of MM cells were detected by flow cytometry. In addition, the expressions of proteins in MM cells were detected by western blot analysis and the secretions of cytokines were measured by ELISA. Our data showed that the expression of SRC3 in bone marrow mesenchymal stem cells (BM-MSCs) could promote cell proliferation and colony formation of MM cells through accelerating the transformation of the G1/S phase, no matter what kind of culture method was adopted. Meanwhile, SRC3 expressed in BM-MSCs could inhibit the apoptosis of MM cells through the caspase apoptosis pathway and mitochondrial apoptosis pathway. Moreover, SRC3 could enhance the adhesion ability of MM cells through up-regulating the expression of adhesion molecules including CXCL4, ICAM1, VLA4, and syndecan-1. SRC3 also played a regulatory role in the progress of MM through the NF-κB and PI-3K/Akt pathways. SRC3 expressed in MSCs was found to promote the growth and survival of MM cells, while SRC3 silencing in MSCs could inhibit the development of MM. These results would be useful for developing a more effective new strategy for MM treatment.

Enhancement of the cytotoxic activity of cytokine-induced killer cells transfected with IL3PE38KDEL gene against acute myeloid leukemia cells.

Cytokine-induced killer (CIK) cells, one of the feasible and effective methods of adoptive immunotherapy, have shown anti-leukemia activity in vivo and in vitro. But the strategy exhibits limited cytotoxic activity in clinical studies. In this study, CIK cells were transfected with an interleukin-3/Pseudomonas exotoxin gene (IL3PE38KDEL). RT-PCR and ELISA were used to verify the expression of IL3PE38KDEL in the transfected CIK cells. These cells released 1,186.7 ± 149.6 pg IL3PE38KDEL/10(4) cells over 48 h into the medium and the culture supernatant selectively killed IL3 receptor(IL3R)-positive HL60 cells, but not IL3R-negative K562 cells. Moreover, IL3PE38KDEL transfection did not influence phenotypes and cytokine production of CIK cells. Co-cultured with leukemia cells, IL3PE38KDEL transfected CIK cells showed enhanced cytotoxicity against IL3R-positive HL60 cells at all effector-to-target (E:T) ratios, but exerted a basal anti-leukemia activity against IL3R-negative K562 cells. Our findings demonstrate that IL3PE38KDEL gene transfection may be a novel strategy for improving anti-leukemia activity of CIK cells.