FOXM1 is an important cell cycle regulator and regulates cell proliferation. In addition, FOXM1 has been reported to contribute to oncogenesis in various cancers. However, it is not clearly understood how FOXM1 contributes to acute myeloid leukemia (AML) cell proliferation. In this study, we investigated the cellular and molecular function of FOXM1 in AML cells. The FOXM1 messenger RNA (mRNA) expressed in AML cell lines was predominantly the FOXM1B isoform, and its levels were significantly higher than in normal high aldehyde dehydrogenase activity (ALDH(hi)) cells. Reduction of FOXM1 expression in AML cells inhibited cell proliferation compared with control cells, through induction of G(2)/M cell cycle arrest, a decrease in the protein expression of Aurora kinase B, Survivin, Cyclin B1, S-phase kinase-associated protein 2 and Cdc25B and an increase in the protein expression of p21(Cip1) and p27(Kip1). FOXM1 messenger RNA (mRNA) was overexpressed in all 127 AML clinical specimens tested (n = 21, 56, 32 and 18 for M1, M2, M4 and M5 subtypes, respectively). Compared with normal ALDH(hi) cells, FOXM1 gene expression was 1.65- to 2.26-fold higher in AML cells. Moreover, the FOXM1 protein was more strongly expressed in AML-derived ALDH(hi) cells compared with normal ALDH(hi) cells. In addition, depletion of FOXM1 reduced colony formation of AML-derived ALDH(hi) cells due to inhibition of Cdc25B and Cyclin B1 expression. In summary, we found that FOXM1B mRNA is predominantly expressed in AML cells and that aberrant expression of FOXM1 induces AML cell proliferation through modulation of cell cycle progression. Thus, inhibition of FOXM1 expression represents an attractive target for AML therapy.

Although hypervirulent Klebsiella pneumoniae (hvKp) has been associated with severe community-acquired infections that occur among relatively healthy individuals, information about hvKp infections in health care settings remains limited. Here, we systematically analyzed the clinical and molecular characteristics of K. pneumoniae isolates causing bloodstream infections in a cross-sectional study. Clinical characteristics of K. pneumoniae bloodstream infections from hospitals across Japan were analyzed by a review of the medical records. Whole-genome sequencing of the causative isolates was performed. Bacterial species were confirmed and hvKp were identified using whole-genome sequencing data. Clinical characteristics of hvKp infections were compared with those of non-hvKp infections by bivariate analyses. Of 140 cases of K. pneumoniae bloodstream infections, 26 cases (18.6%) were caused by various clones of hvKp defined by the carriage of cardinal virulence genes. Molecular identification revealed that 24 (17.1%) and 14 (10%) cases were caused by Klebsiella variicola and Klebsiella quasipneumoniae, respectively. Patients with hvKp infections had higher proportions of diabetes mellitus (risk ratio [RR], 1.75; 95% confidence interval [CI], 1.05 to 2.94), and their infections had significantly higher propensity to involve pneumonia (RR, 5.85; 95% CI, 1.39 to 24.6), liver abscess (RR, 5.85; 95% CI, 1.39 to 24.6), and disseminated infections (RR, 6.58; 95% CI, 1.16 to 37.4) than infections by other isolates. More than one-half of hvKp infections were health care associated or hospital acquired, and a probable event of health care-associated transmission of hvKp was documented. hvKp isolates, which are significantly associated with severe and disseminated infections, are frequently involved in health care-associated and hospital-acquired infections in Japan.

A COVID-19 outbreak occurred in the Diamond Princess cruise ship and we sampled environmental surfaces after passengers and crews vacated the cabins. SARS-CoV-2 RNA was detected from 58 out of 601 samples (10%) from case-cabins 1-17 days after the cabins were vacated, but not from non-case-cabins. There was no difference in the detection proportion between cabins for symptomatic (15%, 28/189, Cq: 29.79-38.86) and asymptomatic cases (21%, 28/131, Cq: 26.21-38.99). No SARS-CoV-2 virus was isolated from any of the samples. Transmission risk of SARS-CoV-2 from symptomatic and asymptomatic patients may be similar and environmental surfaces could be involved in viral transmission.

Persistent thrombocytopenia is a common complication after allogeneic hematopoietic cell transplantation (HCT). Eltrombopag is an oral thrombopoietin receptor agonist whose efficacy against persistent thrombocytopenia after allogeneic HCT has not been well characterized. This retrospective study evaluated the safety and efficacy of eltrombopag in 12 consecutive patients with persistent thrombocytopenia after allogeneic HCT. Eltrombopag was started at 12.5 mg once daily and the dose was increased by 12.5 mg daily every week until platelet counts exceeded 50,000/μL. Five patients had prolonged isolated thrombocytopenia (PIT) and 7 patients had secondary failure of platelet recovery (SFPR). The cumulative incidence rate of successful platelet recovery to ≥50,000/μL without transfusion support was 60% in PIT patients and 71% in SFPR patients. No patients discontinued the drug because of adverse events or intolerability. Notably, the rate of platelet recovery was higher (100% versus 58%; P = .0017) and recovery was faster (median, 33 days versus 137 days; P = .0078) in patients with normal numbers of bone marrow megakaryocytes before starting eltrombopag than in those with decreased numbers of megakaryocytes. Eltrombopag is a promising treatment for both PIT and SFPR after allogeneic HCT. The number of megakaryocytes in bone marrow before eltrombopag treatment may predict the response to eltrombopag.

IMPORTANCE Patients with cancer and health care workers (HCWs) are at high risk of SARS-CoV-2 infection. Assessing the antibody status of patients with cancer and HCWs can help understand the spread of COVID-19 in cancer care. OBJECTIVE To evaluate serum SARS-CoV-2 antibody status in patients with cancer and HCWs during the COVID-19 pandemic in Japan. DESIGN, SETTING, AND PARTICIPANTS Participants were enrolled for this prospective cross-sectional study between August 3 and October 30, 2020, from 2 comprehensive cancer centers in the epidemic area around Tokyo, Japan. Patients with cancer aged 16 years or older and employees were enrolled. Participants with suspected COVID-19 infection at the time of enrollment were excluded. EXPOSURES Cancer of any type and cancer treatment, including chemotherapy, surgery, immune checkpoint inhibitors, radiotherapy, and targeted molecular therapy. MAIN OUTCOMES AND MEASURES Seroprevalence and antibody levels in patients with cancer and HCWs. Seropositivity was defined as positivity to nucleocapsid IgG (N-IgG) and/or spike IgG (S-IgG). Serum levels of SARS-CoV-2 IgM and IgG antibodies against the nucleocapsid and spike proteins were measured by chemiluminescent enzyme immunoassay. RESULTS A total of 500 patients with cancer (median age, 62.5 years [range, 21-88 years]; 265 men [55.4%]) and 1190 HCWs (median age, 40 years [range, 20-70 years]; 382 men [25.4%]) were enrolled.In patients with cancer, 489 (97.8%) had solid tumors, and 355 (71.0%) had received anticancer treatment within 1 month. Among HCWs, 385 (32.3%) were nurses or assistant nurses, 266 (22.4%) were administrative officers, 197 (16.6%) were researchers, 179 (15.0%) were physicians, 113 (9.5%) were technicians, and 50 (4.2%) were pharmacists. The seroprevalence was 1.0% (95% CI, 0.33%-2.32%) in patients and 0.67% (95% CI, 0.29%-1.32%) in HCWs (P = .48). However, the N-IgG and S-IgG antibody levels were significantly lower in patients than in HCWs (N-IgG: β, −0.38; 95% CI, −0.55 to −0.21; P < .001; and S-IgG: β, −0.39; 95% CI, −0.54 to −0.23; P < .001). Additionally, among patients, N-IgG levels were significantly lower in those who received chemotherapy than in those who did not (median N-IgG levels, 0.1 [interquartile range (IQR), 0-0.3] vs 0.1 [IQR, 0-0.4], P = .04). In contrast, N-IgG and S-IgG levels were significantly higher in patients who received immune checkpoint inhibitors than in those who did not (median N-

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has curative potential against hematological malignancies. However, there are concerns about the associated risk of non-relapse mortality (NRM). We performed a retrospective single-center study to assess changes in outcomes after allo-HSCT and causes of NRM over three 5-year periods. The rates of 2-year NRM and overall survival (OS) were 16% and 59%, respectively. We found a significant decrease in NRM (P o 0.001), with 2-year NRM of 26, 14 and 9%, and a significant increase in OS (P = 0.005), with 2-year OS of 52%, 58% and 65%, over the three periods (1998-2002, 2003-2007 and 2008-2012), respectively. Of note, a steady improvement was observed in NRM, period by period, among patients aged 50 years or older, patients who underwent HSCT from an unrelated bone marrow donor and patients who underwent HSCT with a reduced-intensity conditioning regimen. Our data showed that the improved NRM can mainly be attributed to a decreased mortality related to infection after starting systemic steroid as GVHD treatment, and a decreased mortality related to organ failure.

To clarify the clinical features and outcome of Stenotrophomonas maltophilia infection among hematopoietic SCT (HCT) recipients, we retrospectively reviewed the records of 1085 consecutive HCT recipients and identified 42 episodes in 31 HCT recipients with S. maltophilia infection. We compared these recipients with 30 non-HCT patients with S. maltophilia infection. The mortality rate in HCT recipients was significantly higher than that in non-HCT patients (relative risk 5.7, P ¼ 0.04), and we identified seven patients with pulmonary hemorrhage due to S. maltophilia, exclusively in the HCT cohort. Six of these latter seven patients died within 1 day from the onset of hemorrhage and the isolate was identified after death in most cases; one patient, who received empiric therapy for S. maltophilia and granulocyte transfusion, survived for more than 2 weeks. The patients with pulmonary hemorrhage had a more severe and longer duration of neutropenia, persistent fever despite of the use of broad-spectrum antibiotics, complication by pneumonia and higher C-reactive protein levels than those without pulmonary hemorrhage. In conclusion, S. maltophilia was associated with fulminant and fatal pulmonary hemorrhage in HCT recipients. Empiric therapy with antibiotics before the onset of pulmonary hemorrhage may be effective in HCT recipients who carry the conditions identified.

This study aimed to characterize the incidence and risk factors of invasive fungal disease, cytomegalovirus infection, other viral diseases, and gram-negative rod infection after glucocorticoid treatment for severe acute graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation and to elucidate the associations of cumulative steroid dose with the risks of individual infections. The study cohort included 91 consecutive patients who developed maximum grades III and IV acute GVHD at our center. The mean cumulative prednisolone-equivalent dose was 41 mg/kg during the first 4 weeks. The cumulative incidence rates of fungal disease, cytomegalovirus disease, other viral diseases, and gram-negative rod infection at 6 months after glucocorticoid treatment were remarkably high, at 14%, 21%, 28%, and 20%, respectively. GVHD within 26 days after transplantation and low lymphocyte count at GVHD treatment were associated with increased risks of several infections. Cumulative prednisolone-equivalent steroid doses ≥ 55 mg/kg during the first 4 weeks were associated with an increased risk of fungal disease (hazard ratio, 3.65; P = .03) and cumulative doses ≥ 23 mg/kg were associated with an increased risk of non-cytomegalovirus viral diseases (hazard ratio, 4.14; P = .02). Strategies to reduce the risk of infectious complications are needed, particularly for patients who have risk factors and those who receive high cumulative steroid doses.