PD-L1 expression in megakaryocytes and its clinicopathological features in primary myelofibrosis patients.

Myeloproliferative neoplasms (MPNs) are characterized by upregulation of proinflammatory cytokines and immune dysregulation, which provide a reasonable basis for immunotherapy in patients. Megakaryocytes are crucial in the pathogenesis of primary myelofibrosis (PMF), the most clinically aggressive subtype of MPN. In this study, we aimed to explore PD-L1 (programmed death-ligand 1) expression in megakaryocytes and its clinical implications in PMF. We analyzed PD-L1 expression on megakaryocytes in PMF patients by immunohistochemistry and correlated the results with clinicopathological features and molecular aberrations. We employed a two-tier grading system considering both the proportion of cells positively stained and the intensity of staining. Among the 85 PMF patients, 41 (48%) showed positive PD-L1 expression on megakaryocytes with the immune-reactive score ranging from 1 to 12. PD-L1 expression correlated closely with higher white blood cell count (p = 0.045), overt myelofibrosis (p = 0.010), JAK2V617F mutation (p = 0.011), and high-molecular risk mutations (p = 0.045), leading to less favorable overall survival in these patients (hazard ratio 0.341, 95% CI 0.135-0.863, p = 0.023). Our study provides unique insights into the interaction between immunologic and molecular phenotypes in PMF patients. Future work to explore the translational potential of PD-L1 in the clinical setting is needed.

Distinct clinical and biological characteristics of acute myeloid leukemia with higher expression of long noncoding RNA KIAA0125.

Expression of long non-coding RNA KIAA0125 has been incorporated in various gene expression signatures for prognostic prediction in acute myeloid leukemia (AML) patients, yet its functions and clinical significance remain unclear. This study aimed to investigate the clinical and biological characteristics of AML bearing different levels of KIAA0125. We profiled KIAA0125 expression levels in bone marrow cells from 347 de novo AML patients and found higher KIAA0125 expression was closely associated with RUNX1 mutation, but inversely correlated with t(8;21) and t(15;17) karyotypes. Among the 227 patients who received standard chemotherapy, those with higher KIAA0125 expression had a lower complete remission rate, shorter overall survival (OS) and disease-free survival (DFS) than those with lower expression. The prognostic significance was validated in both TCGA and GSE12417 cohorts. Subgroup analyses showed that higher KIAA0125 expression also predicted shorter DFS and OS in patients with normal karyotype or non-M3 AML. In multivariable analysis, higher KIAA0125 expression remained an adverse risk factor independent of age, WBC counts, karyotypes, and mutation patterns. Bioinformatics analyses revealed that higher KIAA0125 expression was associated with hematopoietic and leukemic stem cell signatures and ATP-binding cassette transporters, two predisposing factors for chemoresistance.

Performance of a multiplex PCR pneumonia panel for the identification of respiratory pathogens and the main determinants of resistance from the lower respiratory tract specimens of adult patients in intensive care units.

BACKGROUND: Timely diagnostic investigation to establish the microbial etiology of pneumonia is essential to ensure the administration of effective antibiotic therapy to individual patients. METHODS: We evaluated a multiplex PCR assay panel, the FilmArray® pneumonia panel (FilmArray PP, BioFire Diagnostics), for detection of 35 respiratory pathogens and resistance determinants and compared the performance of the standard-of-care test in intensive care unit patients with lower respiratory tract infections. RESULTS: Among the 59 endotracheal aspirates and bronchoalveolar lavage specimens obtained from 51 adult patients, FilmArray PP was effective in detecting respiratory bacterial pathogens with an overall positive percent agreement of 90% (95% confidence interval [CI], 73.5-97.9%) and negative percent agreement of 97.4% (95% CI, 96.0-98.4%). FilmArray PP semi-quantitative reporting demonstrated a concordance rate of 53.6% for the culture-positive specimens and 86.3% for the culture-negative specimens. FilmArray PP detected 16 viral targets, whereas the conventional viral isolation failed, except influenza A, which showed 100% concordance with PCR. Coinfections were detected in 42.3% of the specimens. Substantial discrepancies were observed in identifying antimicrobial resistance gene targets and in the susceptibility testing. However, FilmArray PP may still be useful at the early stage of pneumonia before culture and susceptibility test reports are available. Consequently, the results of FilmArray PP might alter the antibiotic prescription in 40.7% of the patients. CONCLUSIONS: FilmArray PP offers a rapid and sensitive diagnostic method for lower respiratory tract infections. However, clinical correlation is advised to determine its significance in interpreting multiple pathogens and detection of genes involved in antimicrobial resistance.

Usefulness of the FilmArray meningitis/encephalitis (M/E) panel for the diagnosis of infectious meningitis and encephalitis in Taiwan.

BACKGROUND/PURPOSE: Early recognition of causative pathogens is critical for the appropriate management of central nervous system infection and improved outcomes. The BioFire® FilmArray® Meningitis/Encephalitis Panel (BioFire® ME Panel, BioFire Diagnostics) is the first U.S. Food and Drug Administration (FDA)-approved multiplex PCR assay that allows the rapid detection of 14 pathogens, including bacteria (n = 6), viruses (n = 7), and fungi (n = 1), from cerebrospinal fluid (CSF). The performance of the panel is expected to be dependent on the epidemiology of M/E in different geographical regions. METHODS: In this preliminary study, we used the BioFire® ME Panel in 42 subjects who presented to the emergency department with symptoms of M/E in our hospital. The results were compared to conventional culture, antigen detection, PCR, and various laboratory findings. RESULTS: The panel detected six positive samples, of which five were viral and one bacterial. We observed an overall agreement rate of 88% between the BioFire® ME Panel results and the conventional methods. There were no false-positive findings, but five discordant results were observed for enterovirus, herpes simplex virus type 1, Escherichia coli, and Cryptococcus species. CONCLUSIONS: The BioFire® ME Panel performed equivalently to the traditional PCR methods for virus detection, and better than bacterial cultures. This revolutionary system represents a paradigm shift in the diagnosis of M/E and may aid in the rapid identification of community-acquired M/E. However, the usefulness of this tool is limited in regions with a high prevalence of infectious M/E caused by microorganisms not included in the panel.

Fulminant primary cardiac lymphoma with sudden cardiac death: A case report and brief review.

Primary cardiac lymphoma (PCL) is very rare, with the variable clinical manifestations potentially leading to a delayed diagnosis. PCL is usually detected incidentally through image studies, whereas the diagnosis can be confirmed via analysis of pericardial effusion, endomyocardial biopsy tissue, or surgical specimens. Although no standard therapy has been established for PCL, without treatment, the prognosis is grave, with the estimated overall survival being approximately 1 year. We report a difficult diagnosis and complicated case of fulminant PCL, which is the first comprehensively reported case of PCL with secondary hemophagocytosis. A man presented with progressive dyspnea for 3 weeks, and then sudden cardiac death with ventricular fibrillation occurred. After resuscitation, echocardiography revealed a thickened left ventricular wall and severe mitral regurgitation, and computed tomography showed a right atrial mass with diffuse myocardial lesions. PCL was confirmed through a pathological analysis of specimens collected during mitral valvuloplasty, which also implied extensive myocardial involvement. Bone marrow biopsy demonstrated no evidence of lymphoma involvement, but secondary hemophagocytosis was noted. Despite aggressive chemotherapy, the patient died of sepsis with multiorgan failure 26 days after the operation.

High expression of dedicator of cytokinesis 1 (DOCK1) confers poor prognosis in acute myeloid leukemia.

DOCK family genes encode evolutionarily conserved guanine nucleotide exchange factors for Rho GTPase involving multiple biological functions. Yet the patterns and prognostic significance of their expression in acute myeloid leukemia (AML) remain unexplored. Here we analyzed the expression patterns of 11 DOCK family genes in AML cells based on the array data of 347 patients from our cohort and several other published datasets. We further focused on the implications of the expression of DOCK1 since it was the only one in DOCK family to be associated with survival. Physiological functions and biological pathways associated with DOCK1 were identified using bioinformatics approaches. With a median follow up of 57 months, higher DOCK1 expression was associated with shorter disease free and overall survival. The finding could be validated by two independent cohorts. Multivariate analysis showed higher DOCK1 expression as a strong independent unfavorable prognostic factor. Higher DOCK1 expression was closely associated with older age, higher platelet and peripheral blast counts, intermediate-risk cytogenetics, FLT3-ITD, MLL-PTD and mutations in PTPN11, NPM1, RUNX1, ASXL1 and DNMT3A. Functional enrichment analysis suggested the association of DOCK1 overexpression with several key physiological pathways including cell proliferation, motility, and chemotaxis. Therefore, we suggested that AML with higher DOCK1 expression showed characteristic clinical and biological features. DOCK1 expression is an important prognostic marker and a potential therapeutic target for the treatment of AML. Studies in large prospective cohorts are necessary to confirm our findings. Further mechanistic studies to delineate the role of DOCK1 in the leukemogenesis are warranted.