Detection of myeloma cell-derived microvesicles: a tool to monitor multiple myeloma load

The persistence of tumor load in multiple myeloma (MM) lead to relapse in patients achieving complete remission (CR). Appropriate and effective methods of myeloma tumor load monitoring are important for guiding clinical management. This study aimed to clarify the value of microvesicles in monitoring MM tumor load. Microvesicles in bone marrow and peripheral blood were isolated by differential ultracentrifugation and detected by flow cytometry. Western blotting was applied to assess myosin light chain phosphorylation levels. Flow cytometry to detect Ps⁺CD41a^-, Ps⁺CD41a^-CD138⁺, Ps⁺CD41a^-BCMA⁺ microvesicles from bone marrow can be used to predict myeloma burden, furthermore, Ps⁺CD41a^- microvesicles may as a potential index to MRD test. Mechanistically, the releasing of microvesicles from MM cell was regulated by Pim-2 Kinase via Phosphorylation of MLC-2 protein.

PIM2 kinase regulates the expression of TIGIT and energy metabolism on NK cell in multiple myeloma patients.. [DOI: 10.21203/rs.3.rs-2159151/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background: PIM2 kinase play a vital role in the generation of plasma cell and bone loss in multiple myeloma(MM), which highly related to the tumor progression and as a potential therapy target in MM. In immune cell,PIM2 kinase involved in the regulation of lymphocyte like T cell and B cell, However, its role in NK cells remains unclear. Methods: Single-cell RNA sequencing data were analysed the expression of PIM2 kinase in NK cells from MM patients and healthy donors.Immune checkpoint expression, cell apoptosis, and NK cell function had been evaluated through flow cytometry.Then, NCBI, UCSC, JASPAR and GEPIA database were used to predict promoter of TIGIT.NK-92 cells with ETS-1 knockdown were established by using sh-RNA. Kinase functional assay (ADP-Glo) were used to confirm PIM2 inhibitor from 160 kinds of natural flavonoids compound.Samples treated with or without drugs were analyzed using mass spectrometry and RNA-seq. The oxygen consumption rate (OCR), and the extracellular acidification rate (ECAR) were measured by assay kit. Result: The PIM2 kinase was highly expressed in the NK cells from MM patients based on single-cell sequencing analysis and confirmed in clinical sample by PCR and flow cytometry.Inhibition of PIM2 kinase can increase the function of NK cells and down regulation TIGIT expression. Mechanism, we confirmed that ETS-1 which was directly binding to the promoter of TIGIT was up-regulated by PIM2 kinase, which can lead the strengthened transcription of TIGIT on NK cells.Furthermore, two novel natural flavonoids compound named Kaempferol and Quercetin dihydrate as PIM2 kinase inhibitors exhibiting higher efficiency at low dose in MM cells,while influence the expression of TIGIT and energy metabolism on NK-92 cells. For in vitro experiment,PIM2 kinase inhibitors can activate NK cell killing function and decrease TIGIT expression,while promoted the apoptosis of MM cells irrespective of adding BMSCs or not in co-culture systems BMSCs. Conclusion: PIM2 kinase involved in the regulation of NK cell.Inhibiting PIM2 kinase could down-regulate the expression of TIGIT and improve energy metabolism to enhance NK cell anti myeloma cell.

Dysphagia in patients with brainstem stroke: incidence and outcome

OBJECTIVE

This study was conducted to delineate the incidence and outcome of dysphagia among hospitalized patients who were referred for rehabilitation because of brainstem stroke.

DESIGN

We retrospectively reviewed the medical records of 36 patients who were admitted because of brainstem stroke. Information on the patients' clinical features, feeding status, and the results of clinical and videofluoroscopic swallowing examinations were obtained through chart review. Follow-up interviews were conducted via telephone to learn the general medical condition and feeding status of the patients 7-43 mo after hospital discharge.

RESULTS

A total of 81% of the patients had dysphagia at the time of initial clinical swallowing evaluation, which was performed 10-75 days after the onset of stroke. A total of 79% of the dysphagic individuals depended on tube feeding at the initial evaluation; 22% of all individuals could not resume oral intake at discharge. Statistical analyses revealed a significant association between poor outcome and disease involving the medulla, the presence of a wet voice during the initial swallowing test, and a delay or absence of the swallowing reflex. The incidence of aspiration pneumonia was 11%. There was a correlation between the detection of aspiration by modified barium meal videofluoroscopy and the development of aspiration pneumonia. Follow-up interviews showed that 88% of the 27 patients who were contacted had resumed full oral intake 4 mo after the onset of stroke.

CONCLUSIONS

The incidence of dysphagia was relatively high in our study population. The long-term outcome was favorable.