A survey of nurses to assess transfusion practice at the bedside using an electronic identification system: Experience at a university hospital.

OBJECTIVES: The objective of this study was to assess the performance and recognition of transfusion practice at the bedside by nurses in our hospital, where a barcode-based electronic identification system (EIS) has been used since 2002. BACKGROUND: More than half of the steps in the transfusion chain are dependent on nurses' awareness and skills. METHODS: Our transfusion policy at the bedside includes two-person checking of the patient and two-person signing of the label at the time of collecting blood samples for pre-transfusion testing and two-person blood administration, which generally involved a doctor-nurse pair but sometimes involved two nurses. Anonymous, paper-based questionnaires were sent in January 2018 to 1051 nurses who were working in Juntendo University Hospital, Tokyo, Japan. The questionnaire consisted of three parts: (a) background of respondents, (b) performance of collection of blood samples for pre-transfusion testing and (c) performance of pre-transfusion check procedures at the bedside using an EIS based on a total of 20 questions. RESULTS: There was a good response rate of individual nurses (1006/1051, 96%). Most nurses (>90%) performed two-person checking of the patient and two-person signing of the label at the time of collecting blood samples. Most nurses (>90%) performed two-person blood administration involving a doctor-nurse pair and electronic pre-transfusion check using an EIS before blood administration. CONCLUSIONS: The survey revealed that most nurses complied with our transfusion policy at the bedside, but some nurses did not. Further education/training and continuous support by the transfusion service may be needed for all nurses.

PARP1 V762A polymorphism affects the prognosis of myelodysplastic syndromes.

OBJECTIVE: Myelodysplastic syndromes (MDS), caused by various genetic mutations in hematopoietic stem cells, are associated with highly variable outcomes. Poly (ADP-ribose) polymerase-1 (PARP1) plays an important role in DNA damage repair and contributes to the progression of several types of cancer. Here, we investigated the impact of PARP1 V762A polymorphism on the susceptibility to and prognosis of MDS. METHODS: Samples collected from 105 MDS patients and 202 race-matched healthy controls were subjected to polymerase chain reaction-restriction fragment length polymorphism for genotyping. RESULTS: The allele and genotype frequencies of PARP1 V762A did not differ between MDS patients and the control group. However, MDS patients with the PARP1 V762A non-AA genotype, which is associated with high gene activity, had shorter overall survival rates (P = .01) than those with the AA genotype. Multivariate analysis of overall survival also revealed PARP1 V762A non-AA genotype as a poor prognostic factor (P = .02). When patients were analyzed according to treatment history, the PARP1 V762A non-AA genotype was only associated with poor survival in patients who had received treatment (P = .02). CONCLUSION: PARP1 V762A polymorphism may be an independent prognostic factor for MDS, and a predictive biomarker for MDS treatment.

Prognostic impact of trisomy 21 in follicular lymphoma.

The chromosomal abnormalities associated with follicular lymphoma (FL) prognosis are not fully elucidated. Here, we evaluated the pattern of chromosomal abnormalities in FL, and clarified the correlations between the cytogenetic features and clinical outcome. Cytogenetic analysis was performed using standard methods of Giemsa-banding at diagnosis for 201 FL patients admitted to our hospitals between 2001 and 2013. The identified chromosomal abnormalities were: t(14;18)(q32;q21) (59·2%), +X (17·9%), del(6)(q)/-6 (16·9%), +7 (14·4%), abnormality of 1q12-21/1q (12·9%), del(13)(q)/-13 (11·9%), abnormality of 3q27 (10·4%), abnormality of 10q22-24 (10·0%), +12/dup(12)(q) (10·0%), abnormality of 1p21-22/1p (9·0%), +18 (9·0%), del(17)(p)/-17 (5·0%), and a complex karyotype (54·7%). Patients with trisomy 21 had a significantly shorter progression-free survival (P = 0·00171) and overall survival (OS) (P < 0·001) than those without trisomy 21; additionally, patients with trisomy 21 in the rituximab-treated cohort also had a significantly shorter OS (P = 0·000428). Multivariate analysis identified trisomy 21 as an independent risk factor in our cohorts with or without t(14;18) (P = 0·015). In conclusion, the presence of trisomy 21 was an independent risk factor for in FL. Chromosomal analysis of FL patients at diagnosis can provide useful information about their expected survival.

PDCD1 and CTLA4 polymorphisms affect the susceptibility to, and clinical features of, chronic immune thrombocytopenia.

Programmed death-1 (PD-1, PDCD1) and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4, CTLA4) play central roles in immune checkpoint pathways. Single nucleotide polymorphisms (SNPs) of PDCD1 and CTLA4 have been reported to be associated with susceptibility to some autoimmune diseases. However, the potential association between SNPs in these immune checkpoint genes and risk of chronic immune thrombocytopenia (cITP) remain controversial and obscure. The aims of this study were to clarify the influence of PDCD1 and CTLA4 SNPs on the risk of developing cITP and its clinical features. We obtained genomic DNA from 119 patients with cITP and 223 healthy controls; their genotypes were determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Patients with cITP had a significantly higher frequency of the PDCD1 +7209 TT genotype compared with healthy controls. The CTLA4 -1577 GG genotype and CT60 GG genotype showed higher frequencies of platelet count <5 × 109 /l at diagnosis, minimum platelet count <5 × 109 /l, and bleeding symptoms. Moreover, the PDCD1 -606 AA genotype and +63379 TT genotype were significantly associated with a lower number of patients who achieved a complete response to prednisolone treatment. Our results suggest that the immune checkpoint polymorphisms may affect the susceptibility to the clinical features of cITP, and treatment response of the affected patients.

IL17A and IL23R gene polymorphisms affect the clinical features and prognosis of patients with multiple myeloma.

Single nucleotide polymorphisms (SNPs) in interleukin 17 (IL17A) and IL-23 receptor (IL23R) are involved in the pathogenesis of many cancers and autoimmune diseases. We investigated the influence of IL17A and IL23R SNPs on the risk of developing multiple myeloma (MM) and its clinical features. We obtained genomic DNA from 120 patients with MM and 201 healthy controls and detected IL17A -197 G/A (rs2275913) and IL23R H3Q (rs1884444) genotypes using the polymerase chain reaction-restriction fragment length polymorphism method. There were no significant differences in the genotype and allele frequencies of IL17A -197 G/A and IL23R H3Q between the controls and patients with MM. Compared with the GG and GA genotypes, the IL17A AA genotype was significantly associated with lower hemoglobin levels. The IL23R HH genotype was significantly associated with higher frequency of bone lesions and plasmacytoma than the HQ and QQ genotypes. We observed significant differences in overall survival (OS) between patients treated with thalidomide and/or bortezomib and those treated conventionally. Therefore, we also examined the effect of IL17A and IL23R polymorphisms on the clinical variables and OS in patients treated with thalidomide and/or bortezomib. We observed that the IL23R HH genotype was significantly associated with poor survival compared with the QH and HH genotypes in these patients. Our findings indicate that IL17A -197 G/A and IL23R H3Q are not associated with susceptibility to MM. However, IL-17 and IL-23R polymorphisms may affect severity, bone lesions, and extra-medullary disease in patients with MM. Moreover, IL23R polymorphisms may contribute to poor prognosis in patients with MM treated with thalidomide and/or bortezomib.

A Rare Case of Chronic Active Epstein-Barr Virus (EBV) Infection Accompanied by the Infiltration of EBV-infected CD8+ T Cells into the Muscle.

We describe a rare case of chronic active Epstein-Barr virus (CAEBV) infection, with infiltration of the skeletal muscle. A 19-year-old woman with swollen cervical lymph nodes and a fever was referred to our hospital. Swelling of the trapezium muscle and elevation of creatinine kinase level were observed. Biopsy results of the brachialis muscle revealed infiltration of Epstein-Barr virus (EBV)-encoded RNA-positive CD8 T lymphocytes. The EBV virus load in the peripheral blood was high, and EBV monoclonality was determined by Southern blot analysis. Owing to the rarity of CAEBV with skeletal muscle infiltration, this case alerts physicians to the potential diagnostic pitfalls of CAEBV.

Overexpression of B-cell lymphoma 6 alters gene expression profile in a myeloma cell line and is associated with decreased DNA damage response.

B-cell lymphoma 6 (BCL6) attenuates DNA damage response (DDR) through gene repression and facilitates tolerance to genomic instability during immunoglobulin affinity maturation in germinal center (GC) B cells. Although BCL6 expression is repressed through normal differentiation of GC B cells into plasma cells, a recent study showed the ectopic expression of BCL6 in primary multiple myeloma (MM) cells. However, the functional roles of BCL6 in MM cells are largely unknown. Here, we report that overexpression of BCL6 in a MM cell line, KMS12PE, induced transcriptional repression of ataxia telangiectasia mutated (ATM), a DDR signaling kinase, which was associated with a reduction in γH2AX formation after DNA damage. In contrast, transcription of known targets of BCL6 in GC B cells was not affected, suggesting a cell type-specific function of BCL6. To further investigate the effects of BCL6 overexpression on the MM cell line, we undertook mRNA sequence analysis and found an upregulation in the genomic mutator activation-induced cytidine deaminase (AID) with alteration in the gene expression profile, which is suggestive of de-differentiation from plasma cells. Moreover, interleukin-6 exposure to KMS12PE led to upregulation of BCL6 and AID, downregulation of ATM, and attenuation of DDR, which were consistent with the effects of BCL6 overexpression in this MM cell line. Taken together, these results indicated that overexpression of BCL6 alters gene expression profile and confers decreased DDR in MM cells. This phenotypic change could be reproduced by interleukin-6 stimulation, suggesting an important role of external stimuli in inducing genomic instability, which is a hallmark of MM cells.

Long non-coding RNA MALAT1 is an inducible stress response gene associated with extramedullary spread and poor prognosis of multiple myeloma.

Extramedullary myeloma (EMM) occurs when myeloma develops outside the bone marrow; it often develops after chemotherapy and is associated with the acquisition of chemo-resistance and a fatal course. The mechanisms underlying extramedullary spread have not yet been fully elucidated. MALAT1 is a highly abundantly and ubiquitously expressed long non-coding RNA that plays important roles in cancer metastasis. The aims of this study were to clarify the association of MALAT1 with EMM and to elucidate the underlying mechanism of EMM formation under chemotherapeutic pressure. MALAT1 expression was significantly higher in multiple myeloma (MM) than in monoclonal gammopathy of undetermined significance. Furthermore, MALAT1 expression was markedly higher in EMM compared with that in corresponding intramedullary myeloma cells. A higher MALAT1 level was associated with shorter overall and progression-free survival. MALAT1 expression level was positively correlated with expression of HSP90AA1, HSP90AB1 and HSP90B1 but not with TP53 expression. MALAT1 was significantly upregulated by bortezomib and doxorubicin. Considering the known functions of MALAT1, our results suggest that it acts as a stress response gene that is upregulated by chemotherapy, thereby linking chemotherapy to EMM formation. Elucidating the biological implication of long non-coding RNA contributes to deeper understanding concerning the pathogenesis and investigation of novel therapeutic targets for MM.

Successful Management of a Patient with Autoimmune Hemorrhaphilia due to Anti-Factor XIII/13 Antibodies Complicated by Pulmonary Thromboembolism.

Autoimmune hemophilia-like disease (hemorrhaphilia) due to anti-factor XIII (FXIII) antibodies (AH13) is a very rare, life-threatening bleeding disorder. A 77-year-old woman developed macrohematuria and a right renal pelvic hematoma. The coagulation times were not prolonged, but FXIII activity and antigen levels were severely and moderately reduced to 9 and 29% of normal values, respectively. Accordingly, the FXIII-specific activity turned out to be low. FXIII inhibitor and anti-FXIII-A subunit autoantibodies were detected by a 1:1 crossmixing test and immunoblot and immunochromatographic assays. She was therefore diagnosed with "definite AH13" and treated with plasma-derived FXIII concentrates to arrest the hemorrhage. In addition to a highly compressed inferior vena cava by a huge renal pelvic hematoma, deep vein thrombosis (DVT) and pulmonary thromboembolism (PE) were identified by systemic computed tomography. The patient was immediately started on anticoagulation therapy with low-dose heparin. Emboli disappeared quickly, probably because under-crosslinked thrombi caused by severe FXIII deficiency are vulnerable to fibrinolysis. After about 1.5 years, anti-FXIII-A subunit autoantibodies still remained despite the use of rituximab, steroid pulse therapy, oral prednisolone, and oral cyclophosphamide treatments. In conclusion, an extremely rare AH13 case complicated by DVT and PE was successfully managed by balancing anticoagulation therapy with hemostatic therapy.

Mouse model of endemic Burkitt translocations reveals the long-range boundaries of Ig-mediated oncogene deregulation.

Human Burkitt lymphomas are divided into two main clinical variants: the endemic form, affecting African children infected with malaria and the Epstein-Barr virus, and the sporadic form, distributed across the rest of the world. However, whereas sporadic translocations decapitate Myc from 5' proximal regulatory elements, most endemic events occur hundreds of kilobases away from Myc. The origin of these rearrangements and how they deregulate oncogenes at such distances remain unclear. We here recapitulate endemic Burkitt lymphoma-like translocations in plasmacytomas from uracil N-glycosylase and activation-induced cytidine deaminase-deficient mice. Mapping of translocation breakpoints using an acetylated histone H3 lysine 9 chromatin immunoprecipitation sequencing approach reveals Igh fusions up to ∼350 kb upstream of Myc or the related oncogene Mycn. A comprehensive analysis of epigenetic marks, PolII recruitment, and transcription in tumor cells demonstrates that the 3' Igh enhancer (Eα) vastly remodels ∼450 kb of chromatin into translocated sequences, leading to significant polymerase occupancy and constitutive oncogene expression. We show that this long-range epigenetic reprogramming is directly proportional to the physical interaction of Eα with translocated sites. Our studies thus uncover the extent of epigenetic remodeling by Ig 3' enhancers and provide a rationale for the long-range deregulation of translocated oncogenes in endemic Burkitt lymphomas. The data also shed light on the origin of endemic-like chromosomal rearrangements.

Primary leptomeningeal B-cell lymphoma with normal pressure hydrocephalus at diagnosis.

An 80-year-old man, presenting with gait disturbance and memory loss, had findings of normal pressure hydrocephalus. Primary leptomeningeal lymphoma (PLML) was diagnosed based on cytology and flow cytometry of cerebrospinal fluid obtained by examination. Gadolinium-enhanced MRI showed enhancement of the brain and spinal cord but FDG-PET/CT revealed no lymph node swelling. With intrathecal chemotherapy, meningeal lesions disappeared and the gait disturbance and memory loss improved. However, the disease recurred three months later, manifesting as left facial nerve palsy, but the symptoms disappeared in response to intrathecal chemotherapy and systemic rituximab administration. Although a tumor lesion in the spinal canal was suggested by MRI examination, the patient has maintained a good clinical course for four years with intrathecal chemotherapy every three months. PLML is a very rare disease and its diagnosis is difficult. Repeated intrathecal chemotherapy appeared to be effective against PLML in this case.

[Successful treatment with dasatinib for polycythemia vera patient emerging BCR-ABL positive clone during 13 years of treatment].

Herein, we report a patient with polycythemia vera (PV) who exhibited Philadelphia chromosome (Ph) positive CML-like clinical features after 13 years of hydroxycarbamide administration and successful treatment with a tyrosine kinase inhibitor (TKI). She was 64 years old when initially diagnosed with PV and was confirmed to be negative for BCR-ABL translocation. Thirteen years later, with increasing white blood cell and platelet counts, a BCR-ABL positive clone emerged and the JAK2V617F mutation disappeared. After TKI treatment, the BCR-ABL copy number decreased and the JAK2V617F mutation was again detected. Furthermore, MPN clinical features were observed. This case provides insights into the clonal divergence and growth advantage of the Ph positive clone over the MPN clone. Whether JAK2V617F is an MPN initiating event or a secondary mutation has been a point of discussion for the past several years. This issue is also considered in the present report.

Regulation of AID expression in the immune response.

The B cell-specific enzyme activation-induced cytidine deaminase (AID) has been shown to be essential for isotype switching and affinity maturation of antibody genes during the immune response. Conversely, AID activity has also been linked to autoimmunity and tumorigenesis. Determining how AID expression is regulated in vivo is therefore central to understanding its role in health and disease. Here we use phylogenetic footprinting and high-resolution histone acetylation mapping to accurately demarcate AID gene regulatory boundaries. Based on this strategy, we identify a novel, positive regulatory element required for AID transcription. Furthermore, we generate two AID indicator mouse strains using bacterial artificial chromosomes that faithfully recapitulate endogenous AID expression. The first strain uses a green fluorescent protein reporter to identify B cells that actively express AID during the immune response. In the second strain, AID transcription affects the permanent expression of a yellow fluorescent protein reporter in post-germinal center and terminally differentiated lymphocytes. We demonstrate the usefulness of these novel strains by resolving recent contradictory observations on AID expression during B cell ontogeny.

[Emergence of donor-derived anti-HLA antibody and subsequent transfusion-refractory thrombocytopenia after allogeneic hematopoietic stem cell transplantation from an HLA-matched sibling donor in a patient with acute myeloid leukemia].

A 45-year-old woman with acute myelogenous leukemia developed platelet transfusion refractoriness (PTR) after the engraftment of an allogeneic peripheral blood stem cell transplantation (PBSCT) from her multiparous sister, which was attributed to HLA antibodies that could not be detected in the patient's serum before transplantation. She achieved neutrophil engraftment by day 18 and megakaryocytopoiesis and complete donor chimerism was confirmed in the bone marrow on day 21. IgG-class HLA antibodies were detected in her serum on day 24 after PBSCT; however, on day 15, no HLA antibodies were detected. The specificity of the antibodies that emerged in the patient closely resembled that of the antibodies found in the donor. The donor had probably been immunized during pregnancy by their partner's HLA-antigens expressed by the fetus. Consequently, transplanted donor-derived cells provoked HLA antibodies in the recipient early after PBSCT, and those HLA antibodies induced PTR. The presence of HLA antibodies should be examined at least in pregnant female donors whose recipients developed PTR attributable to HLA antibodies after SCT.

Usefulness of serum creatinine and cystatin C ratio as a screening tool for predicting prognosis in patients with pancreatic cancer.

Aim: This study aimed to evaluate the usefulness of the serum creatinine/cystatin C (Cr/CysC) ratio as a prognostic factor after pancreatic surgery in patients with pancreatic cancer. Methods: We retrospectively analyzed the data of 88 patients with pancreatic ductal carcinoma who underwent pancreatic surgery from January 2017 to December 2020. CysC measured from frozen serum samples and circulating Cr levels were used to calculate the Cr/CysC ratio. The cutoff value of the Cr/CysC ratio was determined using receiver operating characteristic curves. Cox proportional hazards model analysis and survival curves were applied to identify the prognostic factors. Results: The optimal cutoff value of the Cr/CysC ratio for predicting mortality after surgery was 1.05. This study included 20 (22.7%) and 68 (77.3%) patients with high and low Cr/CysC ratios, respectively. The low Cr/CysC ratio was significantly associated with female sex (p = 0.020) and higher levels of C-reactive protein (p = 0.020). The postoperative length of stay was significantly longer in patients with low Cr/CysC rates (p = 0.044). Patients with low Cr/CysC ratio showed poorer prognosis in relapse-free survival (hazard ratio [HR] = 3.33; 95% confidence interval [CI]: 1.54-4.20; p = 0.002) and overall survival (HR = 2.52, 95% CI: 1.04-6.10, p = 0.041), respectively, which were significantly worse than in those with high Cr/CysC ratios (p = 0.003 and 0.049, respectively). Conclusion: The Cr/CysC ratio could be a useful screening tool for predicting the prognosis of patients with pancreatic ductal carcinoma undergoing pancreatic surgery.

The ratio of creatinine and cystatin C estimated glomerular filtration rates as a surrogate marker in patients with hepatocellular carcinoma undergoing hepatic resection.

BACKGROUND: The ratio of creatinine and cystatin C estimated glomerular filtration rates (eGFRcre/eGFRcys) is significantly positively correlated with sarcopenia. However, there are no published reports on the relationship between eGFRcre/eGFRcys and long-term prognosis in patients after hepatic resection for hepatocellular carcinoma (HCC). METHODS: A total of 157 patients who had undergone curative hepatic resection for HCC were retrospectively reviewed. Cystatin C levels were measured in serum samples that had been frozen after collection at surgery. We aimed to investigate the significance of cystatin C in prognostic value following hepatic resection for HCC. RESULTS: The best cut-off eGFRcre/eGFRcys value for overall survival after hepatic resection for HCC was 1.0025. High eGFRcre/eGFRcys was significantly associated with poor liver function, low skeletal muscle mass, large tumor size, large ascitic volume, worse overall and recurrence-free survival. The eGFRcre/eGFRcys was significantly related to severe recurrence patterns (multiple liver recurrences, distant metastasis). CONCLUSIONS: Preoperative eGFRcre/eGFRcys can predict overall and recurrence-free survival in HCC patients undergoing hepatic resection. The eGFRcre/eGFRcys is a simple and reliable surrogate marker that indicates eligibility for hepatic resection for HCC.

Spred-2 suppresses aorta-gonad-mesonephros hematopoiesis by inhibiting MAP kinase activation.

In midgestation mouse embryos, the aorta-gonad-mesonephros (AGM) region generates hematopoietic stem cells and definitive hematopoiesis is regulated by cell-cell interaction and signaling molecules. We showed that a Ras/mitogen-activated protein (MAP) kinase signaling-specific inhibitor and a dominant negative mutant Ras blocked the production of CD45+ hematopoietic cells in embryonic day 11.5 AGM culture, indicating an essential role for the MAP kinase pathway in AGM hematopoiesis. Overexpression of the Ras/MAP kinase pathway regulator, Spred-2, in the AGM culture significantly reduced the number of CD45+ cells. In contrast, production of CD45+ cells from the AGM region of Spred-2-null mice was up-regulated as compared with wild-type littermates. Furthermore, Spred-2-deficient mice exhibited elevated hematopoietic colony formation from vascular endothelial-cadherin+ cells. These data indicate that Spred-2 functions as a negative regulator of AGM hematopoiesis by inhibiting hematopoietic cytokine signaling.

Possible solution for the problem of unread image interpretation reports: the "Gunma University Star Search".

PURPOSE: To propose a new strategy to prevent communication errors caused by unread radiology reports. MATERIALS AND METHODS: Medical emergencies were prefixed with triple stars on radiology reports, and the attending physician was contacted by telephone. Semi-emergencies (medical issues needing addressing within 2 weeks) were prefixed with double stars. Two weeks later, the duty radiologist would search the double-starred reports, and reviewed relevant patient charts to confirm that the information had been appropriately understood and acted upon. If not, the duty radiologist contacted the referral physician by telephone. One year after implementing this strategy, we retrospectively evaluated 1-year worth of data for all the reports of CT, MRI, nuclear medicine and ultrasonography (April 2018 to March 2019). RESULTS: Three hundred and twenty-one reports were double starred (0.52% of 62,143 reports, 1.32 reports/day), and transmission of relevant information was incomplete in 23 cases (7.17%). Causes of incomplete transmission were (1) reports not being opened (n = 17), (2) relevant information on reports being overlooked (n = 5), and (3) the wrong report being opened (n = 1). Sixty-five reports contained triple stars (0.10%, 0.27 reports/day). CONCLUSION: The proposed strategy may be effective in preventing communication errors in radiology reports with important findings requiring semi-emergency clinical action.

IgG4-related Disease with a Cardiac Mass.

A 69-year-old man with palpitations and decreased blood pressure was referred. Echocardiography showed a mass in the right atrium and cardiac septum. The serum IgG4 level was 1,450 mg/dL. A biopsy of the cardiac mass showed fibrosis with inflammatory cells and increased IgG4-positive plasma cells and lymphocytes. Flow cytometry and polymerase chain reaction of the immunoglobulin heavy chain did not demonstrate monoclonality. He was diagnosed with IgG4-related disease (IgG4-RD). IgG4-RD with a cardiac mass is rare and it is difficult to distinguish it from malignant lymphoma by a pathological examination alone. We therefore performed a biopsy and analyzed the clonality in order to make an accurate diagnosis of IgG4-RD.

Integrin α7 and Extracellular Matrix Laminin 211 Interaction Promotes Proliferation of Acute Myeloid Leukemia Cells and Is Associated with Granulocytic Sarcoma.

Acute myeloid leukemia (AML) with granulocytic sarcoma (GS) is characterized by poor prognosis; however, its underlying mechanism is unclear. Bone marrow samples from 64 AML patients (9 with GS and 55 without GS) together with AML cell lines PL21, THP1, HL60, Kasumi-1, and KG-1 were used to elucidate the pathology of AML with GS. RNA-Seq analyses were performed on samples from seven AML patients with or without GS. Gene set enrichment analyses revealed significantly upregulated candidates on the cell surface of the GS group. Expression of the adhesion integrin α7 (ITGA7) was significantly higher in the GS group, as seen by RT-qPCR (p = 0.00188) and immunohistochemistry of bone marrow formalin-fixed, paraffin-embedded (FFPE) specimens. Flow cytometry revealed enhanced proliferation of PL21 and THP1 cells containing surface ITGA7 in the presence of laminin 211 and stimulated ERK phosphorylation; this effect was abrogated following ITGA7 knockdown or ERK inhibition. Overall, high ITGA7 expression was associated with poor patient survival (p = 0.0477). In summary, ITGA7 is highly expressed in AML with GS, and its ligand (laminin 211) stimulates cell proliferation through ERK signaling. This is the first study demonstrating the role of integrin α7 and extracellular matrix interactions in AML cell proliferation and extramedullary disease development.