Merkel cell polyomavirus-negative Merkel cell carcinoma is associated with JAK-STAT and MEK-ERK pathway activation.

Merkel cell polyomavirus (MCPyV) is monoclonally integrated into the genomes of approximately 80% of Merkel cell carcinomas (MCCs). While the presence of MCPyV affects the clinicopathological features of MCC, the molecular mechanisms of MCC pathogenesis after MCPyV infection are unclear. This study investigates the association between MCPyV infection and activation of the MEK-ERK and JAK-STAT signaling pathways in MCC to identify new molecular targets for MCC treatment. The clinicopathological characteristics of 30 MCPyV-positive and 20 MCPyV-negative MCC cases were analyzed. The phosphorylation status of MEK, ERK, JAK, and STAT was determined by immunohistochemical analysis. The activation status of the MEK-ERK and JAK-STAT pathways and the effects of a JAK inhibitor (ruxolitinib) was analyzed in MCC cell lines. Immunohistochemically, the expression of pJAK2 (P = .038) and pERK1/2 (P = .019) was significantly higher in MCPyV-negative than in MCPyV-positive MCCs. Male gender (hazard ratio [HR] 2.882, P = .039), older age (HR 1.137, P < .001), negative MCPyV status (HR 0.324, P = .013), and advanced cancer stage (HR 2.672, P = .041) were identified as unfavorable prognostic factors; however, the phosphorylation states of JAK2, STAT3, MEK1/2, and ERK1/2 were unrelated to the prognosis. The inhibition of cell proliferation by ruxolitinib was greater in MCPyV-negative MCC cell lines than in an MCPyV-positive MCC cell line. The expression of pERK1/2 and pMEK was higher in MCPyV-negative than in MCPyV-positive cell lines. These results suggest that activation of the JAK2 and MEK-ERK pathways was more prevalent in MCPyV-negative than in MCPyV-positive MCC and the JAK inhibitor ruxolitinib inhibited MEK-ERK pathway activation. Consequently, the JAK-STAT and MEK-ERK signaling pathways may be potential targets for MCPyV-negative MCC treatment.

Deficiency of sphingomyelin synthase 2 prolongs survival by the inhibition of lymphoma infiltration through ICAM-1 reduction.

The tumor microenvironment (TME) formation involving host cells and cancer cells through cell adhesion molecules (CAMs) is essential for the multiple steps of cancer metastasis and growth. Sphingomyelin synthase 2 (SMS2) is involved in inflammatory diseases such as obesity and diabetes mellitus by regulation of the SM/ceramide balance. However, the involvement of SMS2 in TME formation and metastasis is largely unknown. Here, we report that SMS2-deficient (SMS2-KO) mice show suppressed the EL4 cell infiltration to liver and prolonged survival time. ICAM-1 was identified as a candidate for the inhibition of TME formation in immortalized mouse embryonic fibroblasts (tMEFs) from mRNA array analysis for CAMs. Reduced SM/ceramide balance in SMS2-KO tMEFs suppressed the attachment of EL4 cells through transcriptional reduction of ICAM-1 by the inhibition of NF-κB activation. TNF-α-induced NF-κB activation and subsequent induction of ICAM-1 were suppressed in SMS2-KO tMEFs but restored by SMS2 re-introduction. In the EL4 cell infiltration mouse model, EL4 injection increased ICAM-1 expression in WT liver but not in SMS2-KO mouse liver. Therefore, inhibition of SMS2 may be a therapeutic target to suppress the infiltration of malignant lymphoma.

Merkel cell polyomavirus and Langerhans cell neoplasm.

BACKGROUND: The relationship between various external agents such as pollen, food, and infectious agents and human sensitivity exists and is variable depending upon individual's health conditions. For example, we believe that the pathogenetic potential of the Merkel cell polyomavirus (MCPyV), the resident virus in skin, is variable and depends from the degree of individual's reactivity. MCPyV as well as Epstein-Barr virus, which are normally connected with humans under the form of subclinical infection, are thought to be involved at various degrees in several neoplastic and inflammatory diseases. In this review, we cover two types of Langerhans cell neoplasms, the Langerhans cell sarcoma (LCS) and Langerhans cell histiocytosis (LCH), represented as either neoplastic or inflammatory diseases caused by MCPyV. METHODS: We meta-analyzed both our previous analyses, composed of quantitative PCR for MCPyV-DNA, proteomics, immunohistochemistry which construct IL-17 endocrine model and interleukin-1 (IL-1) activation loop model, and other groups' data. RESULTS: We have shown that there were subgroups associated with the MCPyV as a causal agent in these two different neoplasms. Comparatively, LCS, distinct from the LCH, is a neoplastic lesion (or sarcoma) without presence of inflammatory granuloma frequently observed in the elderly. LCH is a proliferative disease of Langerhans-like abnormal cells which carry mutations of genes involved in the RAS/MAPK signaling pathway. We found that MCPyV may be involved in the development of LCH. CONCLUSION: We hypothesized that a subgroup of LCS developed according the same mechanism involved in Merkel cell carcinoma pathogenesis. We proposed LCH developed from an inflammatory process that was sustained due to gene mutations. We hypothesized that MCPyV infection triggered an IL-1 activation loop that lies beneath the pathogenesis of LCH and propose a new triple-factor model.

Acute-phase ITIH4 levels distinguish multi-system from single-system Langerhans cell histiocytosis via plasma peptidomics.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a proliferative disorder in which abnormal Langerhans cell (LC)-like cells (LCH cells) intermingle with inflammatory cells. Whether LCH is reactive or neoplastic remains a controversial matter. We recently described Merkel cell polyomavirus (MCPyV) as a possible causative agent of LCH and proposed interleukin-1 loop model: LCH is a reactive disorder with an underlying oncogenic potential and we now propose to test this theory by looking for acute markers of inflammation. We detected MCPyV-DNA in the peripheral blood cells of patients with high-risk organ-type (LCH-risk organ (RO) (+)) but not those with non-high-risk organ-type LCH (LCH-RO (-)); this difference was significant. LCH-RO (-) is further classified by its involvement of either a single organ system (SS-LCH) or multiple organ systems (MS-LCH). In patients with LCH-RO (-), MCPyV-DNA sequences were present in LCH tissues, and significant differences were observed between LCH tissues and control tissues associated with conditions such as dermatopathic lymphadenopathy and reactive lymphoid hyperplasia. Although MCPyV causes subclinical infection in nearly all people and 22 % of healthy adults will harbor MCPyV in their buffy coats, circulating monocytes could serve as MCPyV reservoirs and cause disseminated skin lesions. METHODS: Plasma sample from 12 patients with LCH-RO (-) (5 MS-LCH and 7 SS-LCH) and 5 non-LCH patients were analyzed by peptidomics. Mass spectrometry (MS) spectra were acquired and peptides exhibiting quantitative differences between MS-LCH and SS-LCH patients were targeted. RESULTS: One new candidate biomarker, m/z 3145 was selected and identified after obtaining a MS/MS fragmentation pattern using liquid chromatography-MS/MS. This peak was identified as a proteolytic fragment derived from inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4, [PDB: Q14624]). CONCLUSIONS: Peptidomics of LCH have revealed that the level of acute-phase ITIH4 distinguishes MS-LCH-RO (-) from SS-LCH-RO (-). Acute-phase proteins serve non-specific, physiological immune functions within the innate immune system. LCH may be a reactive disorder with both underlying neoplastic potential of antigen presenting cells harboring BRAF mutations and hyper-immunity of other inflammatory cells against MCPyV infection. Among LCH-RO (-), MCPyV-DNA sequences were present in both MS-LCH tissues and SS-LCH tissues without significant differences. ITIH4 may show that LCH activity or LCH subtypes correlates with the systemic or localized reactions of MCPyV infection.

Interleukin-1 loop model for pathogenesis of Langerhans cell histiocytosis.

We propose Langerhans cell histiocytosis (LCH) is an inflammatory process that is prolonged by mutations. We hypothesize that Merkel cell polyomavirus (MCPyV) infection triggers an interleukin-1 (IL-1) activation loop that underlies the pathogenesis of LCH. Langerhans cells (LCs) are antigen presenting cells in the skin. When LCs encounter exogenous antigens, they migrate from the epidermis into draining lymphoid tissues to initiate T-cell activity. It has been proposed that LC migration-related factors, including E-cadherin, matrix metalloproteinase, and Notch ligand induce LCH activity. We found that the tyrosine phosphatase SHP-1, which binds IL-1 receptor-associated kinase 1, is expressed at a significantly higher level in LCH affecting multiple organ systems (MS-LCH) than in LCH affecting a single organ system (SS-LCH). IL-1 stimulates T helper 17 cells and their signature cytokine IL-17 had been a matter of controversy. We detected higher levels of IL-17A receptor expression in MS-LCH than in SS-LCH and proposed an IL-17 endocrine model that could settle the controversy. IL-1 is the first cytokine secreted in response to sensitizers and promotes LC migration from sentinel tissues. Myeloid differentiation primary response 88 (MyD88), downstream of the IL-1 receptor, has functions in both RAS signaling and inflammation, leading to human cell transformation. In 2010, an activating mutation in the B-rapidly accelerated fibrosarcoma gene (BRAF) V600E was found in LCH. This BRAF mutation induces phosphorylation of the extracellular signal-regulated kinase (ERK) that may play an important role with MyD88 in LCH pathogenesis. However, phosphorylated ERK (pERK) is rapidly dephosphorylated by dual specificity phosphatase 6 (DUSP6), and limited proliferation is predicted in BRAF mutant cells. MyD88 binds pERK via its D-domain, thereby preventing pERK-DUSP6 interaction and maintaining ERK in an active, phosphorylated state. We detected MCPyV-DNA in the peripheral blood cells of two out of three patients with LCH in high-risk organs but not in those of patients with LCH in non-high-risk organs (0/12; P = .029). MCPyV infection can trigger precursor LCH cells with BRAF mutation to produce IL-1; the IL-1 loop is amplified in all LCH subclasses. Our model indicates both BRAF mutation and IL-1 loop regulation as potential therapeutic targets.

Phosphohistone-H3 (PHH3) is prognostic relevant in Merkel cell carcinomas but Merkel cell polyomavirus is a more powerful prognostic factor than AJCC clinical stage, PHH3, Ki-67 or mitotic indices.

Merkel cell carcinomas (MCCs) associated with Merkel cell polyomavirus (MCPyV) have better prognosis than those without MCPyV. The relationship between mitotic index (MI) and MCC outcome has remained elusive because of the difficulty in differentiating mitotic cells from apoptotic ones. We evaluated the role of phosphohistone-H3 (PHH3) (Ser10), a new mitotic count biomarker, in MCPyV-positive or -negative MCC patients, and assessed its prognostic value in comparison to Ki-67 labeling index or MI using hematoxylin and eosin (HE) staining. We compared the prognostic value of PHH3 mitotic index with that of MI by HE in 19 MCPyV-positive and 9 MCPyV-negative MCC patients. PHH3-positive immunoreactivity was mostly observed in mitotic figures. Multivariate analysis significantly showed that MCPyV status (HR, 0.004; 95% CI 0.0003-0.058) and the American Joint Committee of Cancer (AJCC) stage (HR, 5.02; 95% CI 1.23-20.51) were observed as significantly independent prognostic factors for OS. PHH3-positive cell counts/10 HPF was a slightly significant independent prognostic factor for OS (HR, 4.96; 95% CI 0.93-26.55). PHH3-positive MI and MCPyV status in MCC patients are useful in prognostication, although MCPyV-infection is a more powerful prognostic factor in MCCs than the AJCC scheme on proliferation or mitotic indices.

Merkel cell polyomavirus (MCPyV) strains in Japanese merkel cell carcinomas (MCC) are distinct from Caucasian type MCPyVs: genetic variability and phylogeny of MCPyV genomes obtained from Japanese MCPyV-infected MCCs.

Most of merkel cell carcinomas (MCC), a rare, aggressive skin cancer with neuroendocrine features, harbor merkel cell polyomavirus (MCPyV). Seroepidemiological studies suggested high prevalence of MCPyV in the human population. More than ten sequence data on MCPyV strains in Japan have been available, whereas most sequence data were detected from patients living in Europe or European ancestry. Analysis of nine almost complete and 19 partial sequences from two oncogenes, small T antigen (ST) and large T antigen (LT) genomes obtained from 32 Japanese MCPyV-infected MCC revealed that each Japanese MCPyV-infected MCC harbored a specific MCPyV strain with some synonymous or, silent mutations and stop codons or deletions, but functional domains of T antigen had no amino acid changes. All stop codons were localized after retinoblastoma protein-binding domain. These Japanese MCPyV strains were very closely interrelated to themselves and a consensus sequence of Japanese strain was generated. Phylogenetic analysis of our nine sequences and 70 other sequences for ST and LT gene registered in GenBank indicated that Japanese or Asian MCPyV strains formed distinct clades from Caucasian clade, and phylogenetic tree of our nine and 75 other sequences for ST gene formed characteristic three clades and showed that all Japanese or Asian strains were included in the dominant clade. These suggested the possibility of geographically related genotypes of MCPyV. The genomic characterization of MCPyV variants will provide an important database and insights for illuminating their evolutional and biological differences.

Detection of Merkel cell polyomavirus in the human tissues from 41 Japanese autopsy cases using polymerase chain reaction.

It has recently been shown that approximately 80% of Merkel cell carcinomas harbor a novel polyomavirus named Merkel cell polyomavirus (MCPyV). MCPyV has been detected in human tissue samples. However, detailed distribution of MCPyV in non-neoplastic Japanese human tissues remains unclear. To address this, we used single or real-time quantitative polymerase chain reaction (PCR) for 41 autopsy cases. PCR revealed MCPyV-DNA in non-neoplastic samples: total, 29/41 (71%); adult, 29/39 (74%); fetus or infant, 0/2; men, 24/28 (86%); women, 5/13 (38%); total human tissues, 66/572 (12%); skin, 8/15 (53%); adrenal gland, 9/33 (27%), and other 16 organs (4-25%). This study first reported the presence of MCPyV-DNA in non-neoplastic tissues of thyroid gland, adrenal gland, spleen, bone marrow, stomach, gallbladder, pancreas, heart, and aorta. PCR revealed that viral load ranged from 0.00026 to 0.22 in all MCPyV-positive tissues compared with Merkel cell carcinoma samples. These detailed PCR data showed higher prevalence of MCPyV infection in Japanese men than women (p = 0.004) and broad distribution of MCPyV with low viral load in more non-neoplastic human tissues than in the previous reports. These data provide valuable insights for further studies of MCPyV infection and MCPyV-related diseases.

Clinical significance of the expression of FOXP3 and TIGIT in Merkel cell carcinoma.

The pathogenesis of 80% of Merkel cell carcinoma (MCC) cases is associated with Merkel cell polyomavirus (MCPyV). Forkhead helix transcription factor P3 (FOXP3) and the T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domains (TIGIT)-CD155 pathway, which are targets for immunotherapy, were assessed as prognostic factors of MCC. We analyzed mRNA expression data of 111 patients with MCC and performed immunohistochemical analysis to detect the expression of programmed death ligand 1 (PD-L1), CD8, FOXP3, TIGIT, and CD155 in 65 cases of MCC. In CD8 and FOXP3 immunostaining, the number of expressing-infiltrating cells was determined by dividing the region into tumor center and invasive front areas. FOXP3 expression was evaluated separately in cells with high and low intensities. Aberrant TIGIT expression and weak CD155 staining were observed in MCC cells. CD8- and FOXP3-positive cell infiltrations were higher in the invasive front than in the tumor center. Multivariate Cox hazard analysis revealed that high infiltration of cells with low-intensity FOXP3 expression in the invasive front is a favorable prognostic factor (p = 0.025). Thus, targeting TIGIT-CD155 signaling and FOXP3 as well as PD-L1 may be a therapeutic strategy for MCC.

Imaging of Liver Tissues Using a Combination of Silver Impregnation and Low-Vacuum Scanning Electron Microscopy; A Simple Method for the High-Resolution Visualization of Reticulin Structures with Applicability to a Quantitative Analysis.

Background: Low-vacuum scanning electron microscopy (LVSEM) enables the detailed three-dimensional imaging of archival tissues without special pretreatments. The clinical utility of LVSEM in the assessment of liver diseases has not yet been defined. So, we investigated the utility of LVSEM imaging in morphological assessments of normal and diseased liver tissues, with a focus on reticulin structures. Methods: Formalin-fixed tissue samples of two normal livers and two hepatocellular carcinomas with background regenerative nodules/areas were stained with platinum blue stain or silver-impregnated using Watanabe's method and then comparatively observed under LVSEM. We also evaluated the applicability of LVSEM imaging of liver tissues to a quantitative analysis using a digital image analysis technique. Results: Optimal high-resolution images of reticulin structures were obtained using 10-µm-thick silver-impregnated sections. Reticulin fibers were clearly observed to run dendritically around sinusoids in normal livers, and markedly increased in regenerative nodules/areas. Normal reticulin frameworks were lost in hepatocellular carcinoma, leaving a few fragments of reticulin fibers within tumors. Moreover, when a quantitative analysis was applied to these images, we successfully demonstrated a significantly higher reticulin fiber density in regenerative nodules/areas than in the normal liver (P < 0.05). Conclusion: We not only obtained detailed three-dimensional images of reticulin structures in various liver tissues by LVSEM combined with silver impregnation but also showed their applicability to a quantitative analysis. The method presented herein may be applied to future studies for the more accurate diagnosis and better classification/risk stratification of various liver diseases.

Development of a Prognostic Scoring System using MYC Expression and Soluble Interleukin Receptor -2 level for Diffuse Large B-cell Lymphoma.

Background: Diffuse large B-cell lymphoma, not otherwise specified (DLBCL-NOS), is the most frequent type of lymphoid neoplasm. Methods: We investigated the relationships between clinical factors of DLBCL-NOS and MYC immunohistochemistry (IHC) staining. Results: A total of 110 patients diagnosed with DLBCL-NOS from 2012 to 2020 at Tottori University Hospital and treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) chemotherapy were included. IHC staining of MYC in formalin-fixed, paraffin-embedded tumor specimens was performed, and ROC-curve analysis revealed the cut-off value of the MYC positive rate as 55%. The 2-year overall survival (OS) rates of the MYC-negative and -positive groups were 84.7% vs 57.7% (P = 0.0091), and the progression-free survival rates were 77.8% vs 54.7% (P = 0.016), respectively. Multivariate analysis for OS showed prognostic significance of MYC positivity [hazards ratio (HR): 2.496; P = 0.032], and serum levels of soluble interleukin-2 receptor (sIL-2R) > 2000 U/mL (HR: 3.950; P = 0.0019), as well as age > 75 (HR: 2.356; P = 0.068). The original scoring system was developed based on these findings. By assigning one point to each item, age (> 75), MYC positivity, and sIL-2R level (> 2000), all patients were classified into three risk categories: group 1 (0 points), group 2 (1 point), and group 3 (2-3 points). The 2-year survival rates were 100%, 83.0%, and 47.1% for the groups 1, 2, and 3, respectively (P < 0.0001). Conclusion: We suggest that a prognostic scoring system using MYC expression and soluble interleukin receptor -2 level is useful for the prediction of prognosis, contributing to further stratification in DLBCL-NOS.

Belt Electrode-Skeletal Muscle Electrical Stimulation During Early Hematopoietic Post-Transplantation To Prevent Skeletal Muscle Atrophy and Weakness.

A decline in physical functions at the early stage of allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a serious issue. Belt electrode-skeletal muscle electrical stimulation (B-SES) can induce significant muscle contractions with electrical stimulation and reduce muscle weakness. However, this approach has not been used in allo-HSCT patients. This study aimed to examine the effect of B-SES on physical function, and safety in patients during the early post-transplantation period. Forty-three adult patients who underwent B-SES after allo-HSCT were stratified into 2 groups based on the intensity of electrical stimulation (high versus low). B-SES was performed in combination with exercise therapy for 4 post-transplantation weeks. Knee extensor strength (KES) in the low B-SES group decreased significantly, whereas no change was observed in the high-intervention group. A significant positive correlation was observed between total intensity and ΔKES. A reduction in the 6-minute walking distance in the high B-SES group patients was lower than that of historical data. Two patients had B-SES-related complications including muscle pain. This study is the first to propose a new rehabilitation intervention strategy for allo-HSCT. Combined use of B-SES may be a new approach to reducing the decline of physical function in the early post-transplantation period.

Pre-transplant phase angle as a potential marker for predicting the development of infection after allogeneic hematopoietic stem cell transplantation.

BACKGROUND & AIMS: Nutritional assessment in allogeneic hematopoietic stem cell transplantation (allo-HSCT) is important and decreased skeletal muscle mass is a risk factor for the development of infection. Recently, it has become clear that qualitative rather than skeletal muscle mass loss is a marker that reflects post-transplant outcome, but its association with the development of infection remains unclear. Therefore, we assessed skeletal muscle status by body composition using bioelectrical impedance analysis (BIA) and investigated its association with the development of infection. METHODS: A retrospective cohort study was conducted to assess the quantity as well as quality of skeletal muscle using the body composition of BIA assessment. The quantitative (appendicular skeletal muscle mass index; ASM) and qualitative (phase angle; PhA) indicators of skeletal muscle calculated from body composition analysis were used to determine factors influencing the development of infection after allo-HSCT. RESULTS: In total, 80 adult patients, aged 20-70 years (median, 52) were included in this study. The ASM was mildly decreased after allo-HSCT and PhA was significantly decreased. Furthermore, low pre-transplant PhA was identified as an independent risk factor for the development of infection early after transplantation, with a cutoff value of 4.9°. CONCLUSION: In particular, pre-transplant PhA may predict the development of infection early after allo-HSCT, and muscle indices that can be assessed with pre-transplant body composition are a useful evaluation method that can discriminate post-transplant outcomes.

Minimal important difference of the 6-minute walk test after allogenic hematopoietic stem cell transplantation.

PURPOSE: The 6-min walk test (6MWT) of allogenic hematopoietic stem cell transplantation (allo-HSCT) recipients has been gaining attention; however, minimal differences have not been reported. This study aimed to determine the minimal important difference (MID) in the 6MWT among hospitalized patients with allo-HSCT. MATERIALS AND METHODS: The MID of the 6MWT was calculated using three different methodologies based on an anchor-based method; basic anchor-based methods, linear regression analysis, and receiver operating characteristic (ROC) curve analysis. The decrease in the score of Question 2 of the European Organization for Research and Treatment of Cancer Quality of life questionnaire core-30 was included as an anchor question for calculating the MID. Both actual and percentage changes in 6MWT values from baseline and at discharge were used in the MID calculations. In the actual and percentage change of the 6MWT, the one with the larger the area under the curve in the ROC curve was recommended as the MID. RESULTS: Among the three methods using actual values, the largest MID of the 6MWT was -37.5 m (sensitivity: 54%, specificity: 88%). CONCLUSION: More careful follow-up after discharge is necessary for allo-HSCT patients who show a reduction of 37.5 m or more in the acute illness phase.

Advancements in allogeneic hematopoietic stem cell transplantation have improved the survival rates of individuals with malignant hematological disorders, and efforts should now be focused on enhancing their physical function and quality of life.There is a problem that the physical performance of the patients is reduced by the side effects of treatment.More careful follow-up after discharge is necessary for allo-HSCT patients who show a reduction of 37.5 m or more in the acute illness phase.

Intramuscular Adipose Tissue Content Predicts Patient Outcomes after Allogeneic Hematopoietic Stem Cell Transplantation.

During clinical courses involving treatment with allogeneic hematopoietic stem cell transplantation (allo-HSCT), multidisciplinary patient assessment including physical function is indispensable, and quantitative skeletal muscle loss is a poor prognostic marker. Deteriorating quality of muscle from intramuscular adipose tissue degeneration can be important as well, because many patients are cachexic or sarcopenic before allo-HSCT, although this approach has not yet been used in such patients. We conducted this retrospective cohort study to evaluate the quality as well as quantity of skeletal muscle using computed tomography (CT) scans. The psoas muscle mass index (PMI) and radiographic density (RD) calculated by cross-sectional area and averaged CT values of the psoas major muscle at the umbilical level were used to determine the quantity and quality of muscle, respectively. A total of 186 adult patients, ranging in age from 17 to 68 years (median, 49 years), were included in this study, with 46 (24.7%) assigned to the lower PMI group and 49 (26.3%) assigned to the lower RD group. Low RD was identified as an independent risk factor for poor overall survival after allo-HSCT (adjusted hazard ratio [HR], 2.54; P < .01), whereas PMI was not significant. Decreased RD along with a reduced 6-min walking distance before transplantation were significant factors in increased nonrelapse mortality (HR, 2.69; P = .01). This study is the first to suggest the use of a qualitative skeletal muscle index to serve as a prognostic indicator following allo-HSCT. RD should be included in pretransplantation screening parameters, and approaches that include rehabilitation focused on improving both muscle quality and quantity may improve the prognosis of allo-HSCT.

Human Papilloma Virus 18-Positive Submucosal Small Cell Neuroendocrine Carcinoma of the Vagina: An Immunohistochemical and Genomic Study.

Primary vaginal neuroendocrine carcinoma (NEC) is extremely rare among female genital tract tumors. Here, we report 2 cases of vaginal small cell NEC (SCNEC) using immunohistochemistry and next-generation sequencing (NGS) analysis. The 2 patients were in their mid-to-late 70s, presented with abnormal vaginal bleeding and had a vaginal submucosal mass. The biopsied or resected tumors showed a typical neuroendocrine morphology consisting of solid nests of atypical tumor cells, with no specific organoid patterns, and proliferating in the vaginal submucosa. Immunohistochemical analysis showed strong and diffuse expression of chromogranin A, synaptophysin, and p16, but no thyroid transcription factor 1 expression. Additionally, both cases were positive for human papillomavirus (HPV) 18. An NGS-based cancer panel analysis revealed that the tumors carried NF1 and AR mutations, but no major driver mutations were detected. The results of this study suggested that HPV18 infection is linked to vaginal SCNEC.

Subclinical Epstein-Barr Virus Primary Infection and Lytic Reactivation Induce Thyrotropin Receptor Autoantibodies.

Epstein-Barr virus (EBV) is a herpes virus that mainly infects in B lymphocytes and occasionally reactivates lytically. Most individuals have been infected with EBV primarily in their childhood with no symptoms, and the virus persists latently for life. We have previously reported that EBV-infected B cells with thyrotropin receptor autoantibodies (TRAbs) on their surface [TRAb(+) EBV(+) cells] were present in the peripheral blood mononuclear cells (PBMCs) of healthy adult controls and patients with Graves' disease, and that TRAbs released in the culture medium of PBMCs containing TRAb(+) EBV(+) cells by EBV reactivation. EBV lytic reactivation induced the differentiation of host B cells into plasma cells and antibody production. Various autoantibodies have been detected during the acute phase of infectious mononucleosis (IM) that is the symptomatic primary infection of EBV. Therefore, the autoantibody production may be induced by the asymptomatic primary infection. In this study, we examined the presence of TRAb(+) cells, EBV(+) cells, and TRAb(+) EBV(+) cells in PBMCs from 29 healthy or subclinical children without Graves' disease and one cord blood that were divided into six age groups, and also measured plasma TRAb levels. The results obtained demonstrated that low levels of TRAb production occurred with EBV primary infection and lytic reactivation in children without symptoms of IM. Furthermore, the populations of TRAb(+) cells, EBV(+) cells, and TRAb(+) EBV(+) cells were small in the period of primary infection, but they potentially expand with repeated EBV lytic reactivation. This may partly explain why the onset of Graves' disease often occurs in young adults, but rarely in infancy.

Decreased H3K27me3 Expression Is Associated With Merkel Cell Polyomavirus-negative Merkel Cell Carcinoma, Especially Combined With Cutaneous Squamous Cell Carcinoma.

BACKGROUND/AIM: Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine skin cancer, frequently infected with Merkel cell polyomavirus (MCPyV). H3K27me3 acts as a repressive histone modification that epigenetically controls gene transcription. The aim of this study was to examine H3K27me3 expression in MCC. MATERIALS AND METHODS: H3K27me3 expression levels were immunohistochemically analyzed in 20 MCPyV-positive MCCs, 15 MCPyV-negative MCCs with squamous cell carcinoma (SCC) (combined MCCs), and six MCPyV-negative pure MCCs. RESULTS: Reduced H3K27me3 expression was variously observed in MCCs. H3K27me3 H-score was significantly lower in MCPyV-negative MCCs than in MCPyV-positive MCCs (p=0.002). H3K27me3 expression was significantly lower in MCPyV-negative combined MCC component than in MCPyV-positive MCCs (p<0.001), MCPyV-negative pure MCCs (p=0.036), or pure MCC histology (p<0.001). Kaplan-Meier analysis showed no association of H3K27me3 with outcome. CONCLUSION: Differential reduction in H3K27me3 expression was observed based on MCPyV status and morphological type. These results implicate H3K27me3-mediated epigenetic changes in tumorigenesis of MCC, especially in MCPyV-negative MCC combined with SCC.