[Clinical Analysis of Matched Sibling Donor Allogeneic Hematopoietic Stem Cell Transplantation in the Treatment of Young Patients with Multiple Myeloma].

OBJECTIVE: To investigate the efficacy and safety of matched sibling donor allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of young patients with multiple myeloma (MM). METHODS: The clinical data of 8 young patients (median age：46 years) with MM who underwent allo-HSCT from HLA-indentical sibling donors in the First Affiliated Hospital of Chongqing Medical University from June 2013 to September 2021 were collected, and their survival and prognosis were retrospectively analyzed. RESULTS: All the patients were successfully transplanted, and 7 patients could be evaluated the efficacy after transplantation. The median follow-up time was 35.2 (2.5-84.70) months. The complete response (CR) rate was 2/8 before transplantation and 6/7 after transplantation. Acute GVHD developed in 2 cases and extensive chronic GVHD developed in 1 case. Within 100 days, 1 case died of non-recurrent events, and 1-year and 2-year disease-free survival were 6 and 5 cases, respectively. At the end of follow-up, all the 5 patients who survived for more than 2 years survived, and the longest disease-free survival time has reached 84 months. CONCLUSION: With the development of new drugs, HLA-matched sibling donor allo-HSCT may be a curable treatment for young patients with MM.

Roles of functional lipids in bacteriorhodopsin photocycle in various delipidated purple membranes.

Purple membrane (PM) is composed of several native lipids and the transmembrane protein bacteriorhodopsin (bR) in trimeric configuration. The delipidated PM (dPM) samples can be prepared by treating PM with CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate) to partially remove native lipids while maintaining bR in the trimeric configuration. By correlating the photocycle kinetics of bR and the exact lipid compositions of the various dPM samples, one can reveal the roles of native PM lipids. However, it is challenging to compare the lipid compositions of the various dPM samples quantitatively. Here, we utilize the absorbances of extracted retinal at 382 nm to normalize the concentrations of the remaining lipids in each dPM sample, which were then quantified by mass spectrometry, allowing us to compare the lipid compositions of different samples in a quantitative manner. The corresponding photocycle kinetics of bR were probed by transient difference absorption spectroscopy. We found that the removal rate of the polar lipids follows the order of BPG ≈ GlyC < S-TGD-1 ≈ PG < PGP-Me ≈ PGS. Since BPG and GlyC have more nonpolar phytanyl groups than other lipids at the hydrophobic tail, causing a higher affinity with the hydrophobic surface of bR, the corresponding removal rates are slowest. In addition, as the reaction period of PM and CHAPS increases, the residual amounts of PGS and PGP-Me significantly decrease, in concomitance with the decelerated rates of the recovery of ground state and the decay of intermediate M, and the reduced transient population of intermediate O. PGS and PGP-Me are the lipids with the highest correlation to the photocycle activity among the six polar lipids of PM. From a practical viewpoint, combining optical spectroscopy and mass spectrometry appears a promising approach to simultaneously track the functions and the concomitant active components in a given biological system.

Aberrant expression of SPAG6 may affect the disease phenotype and serve as a tumor biomarker in BCR/ABL1-negative myeloproliferative neoplasms.

Sperm-associated antigen 6 (SPAG6) is a newly identified cancer-testis antigen that has been revealed to contribute to the occurrence and development of various types of human cancer, such as ovarian, bladder, breast and lung cancer. However, to the best of our knowledge, the expression levels of SPAG6 in breakpoint cluster region (BCR)/ABL1-negative myeloproliferative neoplasms (MPNs) have not been investigated previously. Using reverse transcription-quantitative PCR and different tissue staining techniques, the present study revealed that SPAG6 was expressed by MPN cells, both at the mRNA and protein levels, and that nucleated erythroid precursors and megakaryocytes expressed the highest levels of SPAG6. In addition, SPAG6, which is known as a microtubule-associated protein, was found to exhibit nucleic, cytoplasmic or both cytoplasmic and nucleic subcellular localization patterns within the same patient or cell type; however, it did not always co-localize with ß-tubulin. Furthermore, SPAG6 expression was revealed to be associated with fewer splenomegaly [P=0.015 for polycythemia vera (PV) and essential thrombocythemia (ET); and P=0.012 for primary myelofibrosis (PMF)] and myelofibrosis events (P=0.014 for PV and ET; and P=0.004 for PMF). In patients with PMF, upregulated expression levels of SPAG6 were also found to be associated with lower white blood cell counts (P=0.042) and lactate dehydrogenase levels (P=0.012), and higher hemoglobin levels (P=0.031) and platelet counts (P=0.025). In addition, the receiver operating characteristic curve analysis indicated that SPAG6 may be a potential biomarker for distinguishing MPN cases from healthy individuals. In conclusion, to the best of our knowledge, the present study is the first to report that aberrant SPAG6 expression may affect the disease phenotype and serve as a tumor biomarker in BCR/ABL1-negative MPNs.