Bone Marrow Adipose Tissue as a Critical Regulator of Postmenopausal Osteoporosis - A Concise Review.

Postmenopausal osteoporosis (PMOP) is a major health problem affecting millions of women worldwide. PMOP patients are often accompanied by abnormal accumulation of bone marrow adipose tissue (BMAT). BMAT is a critical regulator of bone homeostasis, and an increasing BMAT volume is negatively associated with bone mass reduction or fracture. BMAT regulates bone metabolism via adipokines, cytokines and the immune system, but the specific mechanisms are largely unknown. This review emphasizes the impact of estrogen deficiency on bone homeostasis and BMAT expansion, and the mechanism by which BMAT regulates PMOP, providing a promising strategy for targeting BMAT in preventing and treating PMOP.

DCE-MRI to distinguish all monoclonal plasma cell disease stages and correlation with diffusion-weighted MRI/PET-based biomarkers in a hybrid simultaneous whole body-2-[18F]FDG-PET/MRI imaging approach.

BACKGROUND: Dynamic contrast-enhanced-MRI (DCE-MRI) is able to study bone marrow angiogenesis in patients with multiple myeloma (MM) and asymptomatic precursor diseases but its role in the management of MM has not yet been established. The aims of this prospective study was to compare DCE-MRI-based parameters between all monoclonal plasma cell disease stages in order to find out discriminatory parameters and to seek correlations with other diffusion-weighted MRI and positron emission tomography (PET)-based biomarkers in a hybrid simultaneous whole-body-2-[18F]fluorodeoxyglucose (FDG)-PET/MRI (WB-2-[18F]FDG-PET/MRI) imaging approach. METHODS: Patients with newly diagnosed Monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM) or symptomatic MM according to international myeloma working group and underwent WB-2-[18F]FDG-PET/MRI imaging including bone marrow DCE sequences at the Nantes University Hospital were prospectively enrolled in this study before receiving treatment. RESULTS: One hundred and sixty-seven patients (N = 167, mean age: 64 years ± 11 [Standard deviation], 66 males) were considered for the analysis. DCE-MRI-based Peak Enhancement Intensity (PEI), Time to PEI (TPEI) and their maximum intensity time ratio (MITR: PEI/TPEI) values were significantly different between the different monoclonal plasma cell disease stages, PEI values increasing and TPEI values decreasing progressively along the spectrum of plasma cell disorders, from MGUS stage to symptomatic multiple myeloma. PEI values were significantly higher in patients with diffuse bone marrow involvement (either in PET or in MRI images) than in those without diffuse bone marrow involvement, unlike TPEI values. PEI and TPEI values were not significantly different between patients with or without focal bone lesions. CONCLUSION: Different DCE-MRI-based parameters (PEI, TPEI, MITR) could significantly differentiate all monoclonal plasma cell disease stages and complemented conventional MRI and PET-based biomarkers.

Global Transcriptomic and Characteristics Comparisons between Mouse Fetal Liver and Bone Marrow Definitive Erythropoiesis.

Erythropoiesis occurs first in the yolk sac as a transit "primitive" form, then is gradually replaced by the "definitive" form in the fetal liver (FL) during fetal development and in the bone marrow (BM) postnatally. While it is well known that differences exist between primitive and definitive erythropoiesis, the similarities and differences between FL and BM definitive erythropoiesis have not been studied. Here we performed comprehensive comparisons of erythroid progenitors and precursors at all maturational stages sorted from E16.5 FL and adult BM. We found that FL cells at all maturational stages were larger than their BM counterparts. We further found that FL BFU-E cells divided at a faster rate and underwent more cell divisions than BM BFU-E. Transcriptome comparison revealed that genes with increased expression in FL BFU-Es were enriched in cell division. Interestingly, the expression levels of glucocorticoid receptor Nr3c1, Myc and Myc downstream target Ccna2 were significantly higher in FL BFU-Es, indicating the role of the Nr3c1-Myc-Ccna2 axis in the enhanced proliferation/cell division of FL BFU-E cells. At the CFU-E stage, the expression of genes associated with hemoglobin biosynthesis were much higher in FL CFU-Es, indicating more hemoglobin production. During terminal erythropoiesis, overall temporal patterns in gene expression were conserved between the FL and BM. While biological processes related to translation, the tricarboxylic acid cycle and hypoxia response were upregulated in FL erythroblasts, those related to antiviral signal pathway were upregulated in BM erythroblasts. Our findings uncovered previously unrecognized differences between FL and BM definitive erythropoiesis and provide novel insights into erythropoiesis.

Hematopoietic Stem Cells and Their Niche in Bone Marrow.

Extensive research has explored the functional correlation between stem cells and progenitor cells, particularly in blood. Hematopoietic stem cells (HSCs) can self-renew and regenerate tissues within the bone marrow, while stromal cells regulate tissue function. Recent studies have validated the role of mammalian stem cells within specific environments, providing initial empirical proof of this functional phenomenon. The interaction between bone and blood has always been vital to the function of the human body. It was initially proposed that during evolution, mammalian stem cells formed a complex relationship with the surrounding microenvironment, known as the niche. Researchers are currently debating the significance of molecular-level data to identify individual stromal cell types due to incomplete stromal cell mapping. Obtaining these data can help determine the specific activities of HSCs in bone marrow. This review summarizes key topics from previous studies on HSCs and their environment, discussing current and developing concepts related to HSCs and their niche in the bone marrow.

Bone Marrow-Suppressive Treatment in Children Is Associated with Diminished IFN-γ Response from T Cells upon Polyclonal and Varicella Zoster Virus Peptide Stimulation.

Severe haematological diseases and lymphoid malignancies require bone marrow (BM)-suppressive treatments. Knowledge regarding the impact of BM-suppressive treatments on children's memory T cells is very limited. Memory T cells play a crucial role in defending against herpesviruses, which is particularly relevant in paediatric cancer care. We studied 53 children in total; 34 with cancer and 2 with severe haematological disorders, with some receiving BM-suppressive treatment with or without allogeneic-haematopoietic stem cell transplantation (allo-HSCT), alongside 17 healthy controls. We focused on peripheral blood proportions of memory T-cell subsets using flow cytometry and analysed cytokine-secreting T cells with a four-parameter FluoroSpot assay in response to T-cell mitogen and varicella zoster virus (VZV) peptides. Patients on BM-suppressive treatment showed increased clusters of differentiation (CD)4+ and CD8+ effector memory (TEM)/terminally differentiated effector (TEFF) T cells compared to the healthy controls. They also exhibited, amongst other things, when compared to the healthy controls, a reduced total number of cytokine-secreting cells, by means of interferon (IFN)-γ, interleukin (IL)-17A, IL-10, and IL-22, following mitogen activation. A diminished IFN-γ response among the children with BM-suppressive treatment was observed upon VZV-peptide stimulation, compared to the healthy children. Collectively, the findings herein indicate that the children who are undergoing or have finished BM-suppressive treatment display qualitative differences in their T-cell memory compartment, potentially increasing their susceptibility to severe viral infections and impacting their immunotherapy, which relies on the functional ability of autologous T cells.

Evaluation of bone marrow glucose uptake and adiposity in male rats after diet and exercise interventions.

Objectives: Obesity impairs bone marrow (BM) glucose metabolism. Adult BM constitutes mostly of adipocytes that respond to changes in energy metabolism by modulating their morphology and number. Here we evaluated whether diet or exercise intervention could improve the high-fat diet (HFD) associated impairment in BM glucose uptake (BMGU) and whether this associates with the morphology of BM adipocytes (BMAds) in rats. Methods: Eight-week-old male Sprague-Dawley rats were fed ad libitum either HFD or chow diet for 24 weeks. Additionally after 12 weeks, HFD-fed rats switched either to chow diet, voluntary intermittent running exercise, or both for another 12 weeks. BMAd morphology was assessed by perilipin-1 immunofluorescence staining in formalin-fixed paraffin-embedded tibial sections. Insulin-stimulated sternal and humeral BMGU were measured using [18F]FDG-PET/CT. Tibial microarchitecture and mineral density were measured with microCT. Results: HFD rats had significantly higher whole-body fat percentage compared to the chow group (17% vs 13%, respectively; p = 0.004) and larger median size of BMAds in the proximal tibia (815 µm2 vs 592 µm2, respectively; p = 0.03) but not in the distal tibia. Switch to chow diet combined with running exercise normalized whole-body fat percentage (p < 0.001) but not the BMAd size. At 32 weeks of age, there was no significant difference in insulin-stimulated BMGU between the study groups. However, BMGU was significantly higher in sternum compared to humerus (p < 0.001) and higher in 8-week-old compared to 32-week-old rats (p < 0.001). BMAd size in proximal tibia correlated positively with whole-body fat percentage (r = 0.48, p = 0.005) and negatively with humeral BMGU (r = -0.63, p = 0.02). HFD significantly reduced trabecular number (p < 0.001) compared to the chow group. Switch to chow diet reversed this as the trabecular number was significantly higher (p = 0.008) than in the HFD group. Conclusion: In this study we showed that insulin-stimulated BMGU is age- and site-dependent. BMGU was not affected by the study interventions. HFD increased whole-body fat percentage and the size of BMAds in proximal tibia. Switching from HFD to a chow diet and running exercise improved glucose homeostasis and normalized the HFD-induced increase in body fat but not the hypertrophy of BMAds.

[Clinical analysis of the correlation between the expression of soluble B cell maturation antigen and the efficacy of chimeric antigen receptor T cell targeting B cell maturation antigen in patients with multiple myeloma].

Objective: The effect of bone marrow soluble B cell maturation antigen (sBCMA) expression on the efficacy and side effects of chimeric antigen receptor (CAR) -modified T-cell-targeting B cell maturation antigen (BCMA) in patients with multiple myeloma (MM) . Methods: This study involved 29 patients with relapsed or refractory MM (RRMM) who received humanized anti-BCMA CAR-T cell clinical trials from January 2018 to December 2021. The expression of sBCMA in bone marrow before and after anti-BCMA CAR-T cell treatment was detected by flow cytometry and compared. Results: ①Two months after BCMA CAR-T cell treatment, 20 patients (68.97%) achieved an overall response (OR), whereas nine patients had stable disease (SD) or miner emission (MR). ②The expression of sBCMA in the bone marrow of 20 patients with OR was higher before treatment than after [26 926 (18 215, 32 488) ng/L vs 9 968 (6 634, 11 459) ng/L; P<0.001]; no significant difference was observed in patients with MR and SD [41 187 (33 816, 47 046) ng/L vs. 33 954 (31 569, 36 256) ng/L; P=0.145]; sBCMA expression in patients with OR before CAR-T cell treatment was lower than in patients with MR and SD (P=0.005). ③No significant linear correlation was found between the peak value of CAR-T cells and sBCMA expression in the bone marrow of all 29 patients with RRMM (R(2)=0.035, P=0.330). ④No significant difference in sBCMA expression was found between grades 0-1 CRS group (13 patients) and grades 2-4 CRS group [16 patients; 32 045 (18 742, 40 801) ng/L vs 29 102 (24 679, 38 776) ng/L, P=0.879], nor between grade 0 ICANS group (22 patients) and grade 1-3 ICANS group [seven patients; 30 073 (19 375, 40 065) ng/L vs 33 816 (22 933, 43 459) ng/L, P=0.763]. Conclusion: sBCMA expression in the bone marrow is related to the efficacy of BCMA CAR-T cell therapy in patients with RRMM, but is not significantly correlated with the severity of adverse events. It may serve as a predictive biomarker for the efficacy of BCMA CAR-T cell therapy in these patients.

[Introduction of a decalcification method for bone marrow biopsy tissue].

Bone marrow biopsy is one of the important means of hematopathological diagnosis, which has decisive diagnostic significance for various benign and malignant lymphohematopoietic system diseases. Its diagnostic value includes morphological observation, immunohistochemistry, genetics, and molecular biology testing. Owing to the unique nature of bone marrow biopsy, decalcification is an essential step in the pre-treatment process. Its purpose is to remove calcium from bone tissue, preserve intact collagen fiber components, facilitate tissue sectioning, and prevent tissue detachment during staining. If bone marrow biopsy lacks sufficient decalcification, preparing a section is difficult. Conversely, if decalcification is excessive, it can seriously disrupt tissue antigen activity. Therefore, a decalcification method with high decalcification efficiency and mild antigen damage is essential for bone marrow biopsy. This article introduces a bone marrow biopsy tissue decalcification method with high efficiency and less antigen loss: decalcification is performed at room temperature with 12% formic acid and 8% hydrochloric acid decalcification solution on a shaker.

Hematopoietic stem and progenitor cell membrane-coated vesicles for bone marrow-targeted leukaemia drug delivery.

Leukemia is a kind of hematological malignancy originating from bone marrow, which provides essential signals for initiation, progression, and recurrence of leukemia. However, how to specifically deliver drugs to the bone marrow remains elusive. Here, we develop biomimetic vesicles by infusing hematopoietic stem and progenitor cell (HSPC) membrane with liposomes (HSPC liposomes), which migrate to the bone marrow of leukemic mice via hyaluronic acid-CD44 axis. Moreover, the biomimetic vesicles exhibit superior binding affinity to leukemia cells through intercellular cell adhesion molecule-1 (ICAM-1)/integrin ß2 (ITGB2) interaction. Further experiments validate that the vesicles carrying chemotherapy drug cytarabine (Ara-C@HSPC-Lipo) markedly inhibit proliferation, induce apoptosis and differentiation of leukemia cells, and decrease number of leukemia stem cells. Mechanically, RNA-seq reveals that Ara-C@HSPC-Lipo treatment induces apoptosis and differentiation and inhibits the oncogenic pathways. Finally, we verify that HSPC liposomes are safe in mice. This study provides a method for targeting bone marrow and treating leukemia.

No evidence on infectious DNA-based agents in pediatric acute lymphoblastic leukemia using whole metagenome shotgun sequencing.

The etiology of pediatric acute lymphatic leukemia (ALL) is still unclear. Whole-metagenome shotgun sequencing of bone marrow samples in patients with treatment-naïve ALL (n=6) was performed for untargeted investigation of bacterial and viral DNA. The control group consisted of healthy children (n=4) and children with non-oncologic diseases (n=2) undergoing bone marrow sampling. Peripheral blood of all participants was investigated at the same time. After bioinformatical elimination of potential contaminants by comparison with the employed controls, no significant amounts of microbial or viral DNA were identified.

Clinical Characteristics and Diagnosis of Nonaccelerating MDS/MPN-U Patient with Granulocyte Dysplasia.

BACKGROUND: The goal was to improve the clinical cognition of nonaccelerating myelodysplastic/myeloproliferative neoplasms-unclassifiable (MDS/MPN-U) and avoid misdiagnosis or delayed diagnosis. METHODS: The clinical manifestations, laboratory indicators, histopathology, and therapeutic effects of a patient with nonaccelerating MDS/MPN-U were analyzed and the relevant literature was reviewed. RESULTS: Blood routine: white blood cell 98.48 x 109/L, red blood cell 3.20 x 1012/L, basophils 0.42 x 109/L, eosinophils 1.31 x 109/L, hemoglobin 112 g/L, and platelet 113 x 109/L. Blood smears showed granulocytosis and cells at various stages, polylobular granulocytes also can be seen. Bone marrow images show granulocytosis and dysplastic neutrophils, such as binuclear granulocyte, cyclic nuclear granulocyte, nuclear punch, cytoplasm vacuoles, polylobular granulocytes and so on. Bone marrow biopsy: Bone marrow proliferation tumor, combined with cell morphology and molecular biochemistry is recommended. Gene test showed Jak-2 positive, BCR/ABL and MPL negative. Chromosome examination indicated the presence of 46, XY, add (2)(p25), del (12) (p11.2p13)[16]/46, XY. CONCLUSIONS: MDS/MPN-U with granulocytosis and dysplastic neutrophils is rare, mostly in the elderly, and the diagnosis should be made except for other myeloid tumors. Currently, there is no uniform treatment guideline or expert consensus. The treatment options are limited and need to be further confirmed by more studies. MDS/ MPN-U with granulocytosis and dysplastic neutrophils has adverse prognostic factors such as advanced age, increase of bone marrow original cells and related gene mutations. Whether the adverse prognosis is related to specific gene mutations and cytogenetic variation remains to be clarified by more research data.

The novel HLA-C*04:01:01:182 allele identified in a candidate bone marrow donor by next-generation sequencing.

HLA-C*04:01:01:182 differs from the HLA-C*04:01:01:06 allele by one nucleotide substitution in the 5'UTR.

The novel HLA-C*14:02:01:31 allele identified in a candidate bone marrow donor by next-generation sequencing.

Characterisation of the novel HLA-C*14:02:01:31 allele in a 21-year-old Greek bone marrow donor.

Long-termin vitromaintenance of plasma cells in a hydrogel-enclosed human bone marrow microphysiological 3D model system.

Plasma cells (PCs) in bone marrow (BM) play an important role in both protective and pathogenic humoral immune responses, e.g. in various malignant and non-malignant diseases such as multiple myeloma, primary and secondary immunodeficiencies and autoimmune diseases. Dedicated microenvironmental niches in the BM provide PCs with biomechanical and soluble factors that support their long-term survival. There is a high need for appropriate and robust model systems to better understand PCs biology, to develop new therapeutic strategies for PCs-related diseases and perform targeted preclinical studies with high predictive value. Most preclinical data have been derived fromin vivostudies in mice, asin vitrostudies of human PCs are limited due to restricted survival and functionality in conventional 2D cultures that do not reflect the unique niche architecture of the BM. We have developed a microphysiological, dynamic 3D BM culture system (BM-MPS) based on human primary tissue (femoral biopsies), mechanically supported by a hydrogel scaffold casing. While a bioinert agarose casing did not support PCs survival, a photo-crosslinked collagen-hyaluronic acid (Col-HA) hydrogel preserved the native BM niche architecture and allowed PCs survivalin vitrofor up to 2 weeks. Further, the Col-HA hydrogel was permissive to lymphocyte migration into the microphysiological system´s circulation. Long-term PCs survival was related to the stable presence in the culture of soluble factors, as APRIL, BAFF, and IL-6. Increasing immunoglobulins concentrations in the medium confirm their functionality over culture time. To the best of our knowledge, this study is the first report of successful long-term maintenance of primary-derived non-malignant PCsin vitro. Our innovative model system is suitable for in-depthin vitrostudies of human PCs regulation and exploration of targeted therapeutic approaches such as CAR-T cell therapy or biologics.

miR-15a targets the HSP90 co-chaperone Morgana in chronic myeloid leukemia.

Morgana is a ubiquitous HSP90 co-chaperone protein coded by the CHORDC1 gene. Morgana heterozygous mice develop with age a myeloid malignancy resembling human atypical myeloid leukemia (aCML), now renamed MDS/MPN with neutrophilia. Patients affected by this pathology exhibit low Morgana levels in the bone marrow (BM), suggesting that Morgana downregulation plays a causative role in the human malignancy. A decrease in Morgana expression levels is also evident in the BM of a subgroup of Philadelphia-positive (Ph+) chronic myeloid leukemia (CML) patients showing resistance or an incomplete response to imatinib. Despite the relevance of these data, the mechanism through which Morgana expression is downregulated in patients' bone marrow remains unclear. In this study, we investigated the possibility that Morgana expression is regulated by miRNAs and we demonstrated that Morgana is under the control of four miRNAs (miR-15a/b and miR-26a/b) and that miR-15a may account for Morgana downregulation in CML patients.

[Application of automatic slide-dropping instrument in bone marrow chromosomal karyotyping].

OBJECTIVE: To explore the application of an automatic slide-dropping instrument in bone marrow chromosomal karyotyping. METHODS: The effects of manual and automatic dropping methods under different environmental humidity were retrospectively analyzed, and the repeatability of the automatic dropping method was analyzed. RESULTS: No statistical difference was found between the results of automatic and manual dropping methods under the optimum ambient humidity and high humidity (P > 0.05). At low humidity, there was a statistical difference between the two methods (P < 0.05). With regard to the repeatability, the coefficient of variations of the automatic dropping method for the number of split phases, the rate of good dispersion and the rate of overlap were all lower than those of the manual dropping method. A statistical difference was also found in the number of split phases (P < 0.05) but not in the discrete excellent rate and overlapping rate between the two methods (P > 0.05). CONCLUSION: Better effect can be obtained by the automatic dropping instrument. It is suggested to gradually replace manual work with machine.

[18F]F-AraG imaging reveals association between neuroinflammation and brown- and bone marrow adipose tissue.

Brown and brown-like adipose tissues have attracted significant attention for their role in metabolism and therapeutic potential in diabetes and obesity. Despite compelling evidence of an interplay between adipocytes and lymphocytes, the involvement of these tissues in immune responses remains largely unexplored. This study explicates a newfound connection between neuroinflammation and brown- and bone marrow adipose tissue. Leveraging the use of [18F]F-AraG, a mitochondrial metabolic tracer capable of tracking activated lymphocytes and adipocytes simultaneously, we demonstrate, in models of glioblastoma and multiple sclerosis, the correlation between intracerebral immune infiltration and changes in brown- and bone marrow adipose tissue. Significantly, we show initial evidence that a neuroinflammation-adipose tissue link may also exist in humans. This study proposes the concept of an intricate immuno-neuro-adipose circuit, and highlights brown- and bone marrow adipose tissue as an intermediary in the communication between the immune and nervous systems. Understanding the interconnectedness within this circuitry may lead to advancements in the treatment and management of various conditions, including cancer, neurodegenerative diseases and metabolic disorders.

Effects of Recombinant α1-Microglobulin on Early Proteomic Response in Risk Organs after Exposure to 177Lu-Octreotate.

Recombinant α1-microglobulin (A1M) is proposed as a protector during 177Lu-octreotate treatment of neuroendocrine tumors, which is currently limited by bone marrow and renal toxicity. Co-administration of 177Lu-octreotate and A1M could result in a more effective treatment by protecting healthy tissue, but the radioprotective action of A1M is not fully understood. The aim of this study was to examine the proteomic response of kidneys and bone marrow early after 177Lu-octreotate and/or A1M administration. Mice were injected with 177Lu-octreotate and/or A1M, while control mice received saline or A1M vehicle solution. Bone marrow, kidney medulla, and kidney cortex were sampled after 24 h or 7 d. The differential protein expression was analyzed with tandem mass spectrometry. The dosimetric estimation was based on 177Lu activity in the kidney. PHLDA3 was the most prominent radiation-responsive protein in kidney tissue. In general, no statistically significant difference in the expression of radiation-related proteins was observed between the irradiated groups. Most canonical pathways were identified in bone marrow from the 177Lu-octreotate+A1M group. Altogether, a tissue-dependent proteomic response followed exposure to 177Lu-octreotate alone or together with A1M. Combining 177Lu-octreotate with A1M did not inhibit the radiation-induced protein expression early after exposure, and late effects should be further studied.

[Correlation analysis of polyclonal plasma cell proportion in the bone marrow with clinical characteristics of patients with newly diagnosed multiple myeloma].

Objective: To explore the correlation of bone marrow polychonal plasma cell proportion (pPC% ) and clinical features in newly diagnosed multiple myeloma (NDMM) patients. Methods: A retrospective analysis of 317 patients with NDMM admitted to Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2018 to January 2023 was performed. The results of the pPC% in all patients were clear. The relationship between the pPC% and clinical characteristics was analyzed. Results: A total of 317 patients were included, comprising 180 males and 137 females. The median age at diagnosis was 61 (26-91) years, and 55.8% were 60 years or older. The pPC% in the bone marrow of patients with NDMM was different in the DS, International Staging System (ISS), and revised ISS (R-ISS) stages (P=0.002, 0.010, and 0.049, respectively), whereas no statistical difference in pPC% was observed among patients with different FISH risk stratigrams (P=0.971). The correlation coefficient between pPC% and hemoglobin (HGB) at the first diagnosis in patients was 0.211 (P<0.01). The correlation coefficients with serum calcium, serum creatinine, M protein level, and ß(2)-microglobulin were -0.141, -0.120, -0.181, and -0.207, respectively, and the results of the significance test were P=0.012, 0.033, 0.004, and 0.002, respectively, indicating a negative correlation. Compared with the patients with a pPC% of ≥2.5%, the group of patients with a pPC% of <2.5% had significantly higher levels of light chain, serum calcium, serum creatinine, M protein, and ß(2)-microglobulin at the initial diagnosis (P<0.05) ; lower HGB level (P<0.001) ; and a higher proportion of patients in ISS stage Ⅲ (P=0.034) . Conclusion: In this study, the pPC% in patients with NDMM was associated with clinical features of good prognosis, including higher HGB, lower serum calcium, serum creatinine, M protein quantity, ß(2)-microglobulin, light chain involvement, lower proportion of advanced disease (DS stage and ISS stage Ⅲ), and clinical features showing lower tumor burden.

Bone marrow fibrosis in newly diagnosed multiple myeloma and its correlation with clinicopathological factors.

BACKGROUND: Bone marrow fibrosis (BMF) severely impacts both the quality of life and the efficacy of diagnostic procedures. However, the correlation between BMF and clinicopathological features, cytogenetic changes, and prognosis of newly diagnosed multiple myeloma (NDMM) remains unclear. This study determined the incidence, patient characteristics, and clinical outcomes of patients with NDMM with BMF. METHODS: The clinical data, histological features, and clinical outcomes of patients with NDMM were collected. Reticular fiber staining was performed on the enrolled cases, and the degree of reticular fiber overgrowth was graded. Patients with MF-2 and MF-3 were classified as the BMF+ group, and those with MF-0 and MF-1 were classified as the BMF- group, and BMF incidence was calculated. The differences in clinical data, histological features, and clinical outcomes between the BMF+ group and the BMF- group were compared. RESULTS: A consecutive series of 146 patients with NDMM were included. The incidence of MF-0, MF-1, MF-2, and MF-3 was 7.53% (11/146), 34.93% (51/146), 51.37% (75/146), and 6.16% (9/146), respectively. The incidence of BMF-MF-2 and MF-3-was 57.53% (84/146). A significant correlation was identified between the pattern of infiltration and BMF (P < 0.001). In the BMF- group, the distribution of cases with interstitial, nodular, and diffuse infiltration of plasma cells was 16 (25.8%), 21 (33.9%), and 25 (40.3%), respectively. Conversely, in the BMF+ group, these values for interstitial, nodular, and diffuse tumor cells were 9 (10.7%), 15 (17.9%), and 60 (71.4%). Furthermore, BMF was associated with a diffuse infiltration pattern. The overall survival (OS) of the BMF+ group (39.1 months; 95% confidence interval [CI]: 34.0-44.3) was lower than that of the BMF- group (45.4 months; 95% CI: 39.5-51.3), but there was no significant difference between the two groups (P = 0.221). Univariate and multivariate analyses showed that the BMF+ status was not associated with OS in patients with NDMM (P = 0.381 and P = 0.748, respectively). CONCLUSIONS: Our findings suggest that BMF is linked to a diffuse infiltration pattern, and its occurrence is not related to the prognosis of patients with NDMM, providing a basis for further exploring the BMF value in NDMM diagnosis and treatment.