Myelodysplastic syndromes/neoplasms: recent classification system based on World Health Organization Classification of Tumors - International Agency for Research on Cancer for Hematopoietic and Lymphoid Tissues

Real-world Effectiveness of Azacitidine in Treatment-Naive Patients With Higher-risk Myelodysplastic Syndromes

INTRODUCTION

Azacitidine (AZA) is an approved frontline therapy for higher-risk myelodysplastic syndromes (HR-MDS); however, poor survival denotes unmet needs to increase depth/duration of response (DOR).

METHODS

This retrospective study with patient chart review evaluated AZA effectiveness in 382 treatment-naive patients with HR-MDS from a US electronic health record (EHR)-derived database. Responses were assessed using International Working Group (IWG) 2006 criteria; real-world equivalents were derived from EHRs. Primary endpoint was IWG 2006-based complete remission rate (CRR). Secondary endpoints were EHR-based CRR, IWG 2006- and EHR-based objective response rates (ORRs), duration of CR, DOR, progression-free survival, time-to-next-treatment, and overall survival (OS).

RESULTS

Using IWG 2006 criteria, the CRR was 7.9% (n = 30); median duration of CR was 12.0 months (95% CI, 7.7-15.6). In poor cytogenetic risk (n = 101) and TP53 mutation (n = 46) subgroups, CRRs were 7.9% (n = 8) and 8.7% (n = 4), respectively. ORR was 62.8% (n = 240), including a hematologic improvement rate (HIR) of 46.9% (n = 179). Using EHR-based data, CRR was 3.7% (n = 14); median duration of CR was 13.5 months (95% CI, 4.5-21.5). ORR was 67.8% (n = 259), including an HIR of 29.3% (n = 112). Median follow-up was 12.9 months; median OS was 17.9 months (95% CI, 15.5-21.7).

CONCLUSIONS

Consistent with other studies, CRRs and median OS with AZA in treatment-naive patients with HR-MDS were low in this large, real-world cohort. Novel agents/combinations are urgently needed to improve these outcomes in HR-MDS.

U2AF1 in various neoplastic diseases and relevant targeted therapies for malignant cancers with complex mutations (Review)

U2 small nuclear RNA auxiliary factor 1 (U2AF1) is a multifunctional protein that plays a crucial role in the regulation of RNA splicing during eukaryotic gene expression. U2AF1 belongs to the SR family of splicing factors and is involved in the removal of introns from mRNAs and exon-exon binding. Mutations in U2AF1 are frequently observed in myelodysplastic syndrome, primary myelofibrosis, chronic myelomonocytic leukaemia, hairy cell leukaemia and other solid tumours, particularly in lung, pancreatic, and ovarian carcinomas. Therefore, targeting U2AF1 for therapeutic interventions may be a viable strategy for treating malignant diseases. In the present review, the pathogenic mechanisms associated with U2AF1 in different malignant diseases were summarized, and the potential of related targeting agents was discussed. Additionally, the feasibility of natural product-based therapies directed against U2AF1 was explored.

Integrating AI and ML in Myelodysplastic Syndrome Diagnosis: State-of-the-Art and Future Prospects

Myelodysplastic syndrome (MDS) is composed of diverse hematological malignancies caused by dysfunctional stem cells, leading to abnormal hematopoiesis and cytopenia. Approximately 30% of MDS cases progress to acute myeloid leukemia (AML), a more aggressive disease. Early detection is crucial to intervene before MDS progresses to AML. The current diagnostic process for MDS involves analyzing peripheral blood smear (PBS), bone marrow sample (BMS), and flow cytometry (FC) data, along with clinical patient information, which is labor-intensive and time-consuming. Recent advancements in machine learning offer an opportunity for faster, automated, and accurate diagnosis of MDS. In this review, we aim to provide an overview of the current applications of AI in the diagnosis of MDS and highlight their advantages, disadvantages, and performance metrics.

Detection of primary myelofibrosis in blood serum via Raman spectroscopy assisted by machine learning approaches; correlation with clinical diagnosis

Primary myelofibrosis (PM) is one of the myeloproliferative neoplasm, where stem cell-derived clonal neoplasms was noticed. Diagnosis of this disease is based on: physical examination, peripheral blood findings, bone marrow morphology, cytogenetics, and molecular markers. However, the molecular marker of PM, which is a mutation in the JAK2V617F gene, was observed also in other myeloproliferative neoplasms such as polycythemia vera and essential thrombocythemia. Therefore, there is a need to find methods that provide a marker unique to PM and allow for higher accuracy of PM diagnosis and consequently the treatment of the disease. Continuing, in this study, we used Raman spectroscopy, Principal Components Analysis (PCA), and Partial Least Squares (PLS) analysis as helpful diagnostic tools for PM. Consequently, we used serum collected from PM patients, which were classified using clinical parameters of PM such as the dynamic international prognostic scoring system (DIPSS) for primary myelofibrosis plus score, the JAK2V617F mutation, spleen size, bone marrow reticulin fibrosis degree and use of hydroxyurea drug features. Raman spectra showed higher amounts of C-H, C-C and C-C/C-N and amide II and lower amounts of amide I and vibrations of CH3 groups in PM patients than in healthy ones. Furthermore, shifts of amides II and I vibrations in PM patients were noticed. Machine learning methods were used to analyze Raman regions: (i) 800 cm-1 and 1800 cm-1, (ii) 1600 cm-1-1700 cm-1, and (iii) 2700 cm-1-3000 cm-1 showed 100 % accuracy, sensitivity, and specificity. Differences in the spectral dynamic showed that differences in the amide II and amide I regions were the most significant in distinguishing between PM and healthy subjects. Importantly, until now, the efficacy of Raman spectroscopy has not been established in clinical diagnostics of PM disease using the correlation between Raman spectra and PM clinical prognostic scoring. Continuing, our results showed the correlation between Raman signals and bone marrow fibrosis, as well as JAKV617F. Consequently, the results revealed that Raman spectroscopy has a high potential for use in medical laboratory diagnostics to quantify multiple biomarkers simultaneously, especially in the selected Raman regions.

Cytogenetic and cytokine profile in elderly patients with cytopenia

In the elderly with cytopenia, the diagnosis of myelodysplastic syndrome (MDS) may be missed. Cytokine levels contribute to the pathology of MDS. Hence, the objectives were to evaluate cytogenetic profile as a prognostic indicator in risk stratification and cytokine levels as a screening tool in patients with cytopenia for diagnosis. Over 2 years (2016-2018), 150 elderly patients were screened. MDS diagnosis was confirmed by morphology. Interleukin-2 (IL-2) and IL-6 levels were assessed in 50 patients, and karyotyping was performed in 20 confirmed cases of MDS. Age-matched healthy controls were used for comparison of cytokine levels. Among 150 patients, 88.6% had anemia, including nutritional anemia (51.2%). MDS diagnosis was confirmed in 35 patients. In 15 patients, unexplained cytopenia (UC) was present. Karyotyping in 20 MDS patients was normal in 15 (75%) patients and revealed a complex karyotype in four (20%) patients and double chromosomal abnormality in one (5%) patient. The Revised International Prognostic Scoring System (IPSS-R) scored 91% in the low-risk group and 9% (n = 3) in the high-risk group; the latter three developed acute myeloid leukemia (AML) and two of them had a 7q deletion. Among the 15 cases of UC, one patient died from refractory anemia. No significant difference in levels of IL-2 and IL-6 were found between MDS and UC patients when compared with healthy controls, as well as between different risk groups and karyotypes. A significant difference in IL-2 levels was found in MDS patients with disease progression and with stable disease. On the basis of the findings, it is suggested that IL-2 levels will help in predicting disease progression.

Diagnostic challenge of aleukemic leukemia cutis preceding acute myelogenous leukemia: A case report

Aleukemic leukemia cutis is a rare condition in which malignant white cells invade the skin before they appear in the peripheral blood or bone marrow. It is often associated with a poor prognosis. The condition presents a diagnostic challenge as its manifestations are quite variable terms of lesion type. It can manifest as papules, nodules, and/or plaques, and in rare cases erythematous macules, blisters, and ulcers. The most commonly affected areas of the body are the lower extremities, followed by the upper extremities, back, trunk, and face. Due to the non-specific presentation of the disease, skin biopsy and comprehensive immunohistochemical testing can be extremely helpful in the diagnostic work-up. We describe a case of leukemia cutis presenting prior to acute myelogenous leukemia that was initially misdiagnosed as hyper-IgG4 disease.

Intraoperative radiation exposure in hip arthroscopy: a systematic review

Fluoroscopy is used in hip arthroscopy (HA) for portal placement, instrument localisation, and guidance in bony resection. The recent increase in arthroscopic hip procedures may place patients and surgeons at risk for increased radiation exposure and radiation-induced complications. The purpose of the current systematic review was to assess intraoperative radiation exposure in HA. The systematic review was conducted according to PRISMA guidelines; inclusion criteria were studies assessing radiation exposure in HA. 9 studies including 994 patients were included. Mean age was 38.6 years and 48% (436 of 906) were female. Mean time of fluoroscopy exposure was 0.58 minutes. Dose area product was 129.5 cGycm². Mean intraoperative absorbed radiation dose studies was 12.6 mGy. Mean intraoperative effective dose was 0.48 mSv. The mean occupational exposure to the surgeon per case was 0.0031 mSv. Higher patient body mass index (BMI) correlated to greater patient effective and cumulative dose (p < 0.05, r = 0.404), and greater occupational exposure (p < 0.001, r = 0.460). Increasing surgeon experience decreased fluoroscopy time (p = 0.039) and radiation dose (p = 0.002). Radiation dose and effective dose were well under the thresholds for deterministic effects (2 Gy) and annual radiation exposure for occupational workers (20 mSv). Intraoperative radiation exposure to patients and surgeons is within acceptable annual radiation limits. Ensuring careful selection of perioperative imaging modalities, proper protective shielding, specifically the use of leaded eyeglasses, and optimal C-arm positioning are key strategies to reduce radiation exposure to patients and surgeons alike.

The Key microRNAs Regulated the Development of Non-small Cell Lung Cancer by Targeting TGF-β-induced epithelial-mesenchymal Transition

PURPOSE

Epithelial-to-Mesenchymal Transition (EMT) was reported to play a key role in the development of Non-Small Cell Lung Cancer (NSCLC). The process of EMT is regulated by the changes of miRNAs expression. However, it is still unknown which miRNA changed the most in the process of canceration and whether these changes played a role in tumor development.

METHODS

A total of 36 SCLC patients treated in our hospital between 11th, 2015 and 10th, 2017 were enrolled. The samples of cancer tissues and paracancer tissues of patients were collected and analyzed. Then, the miRNAs in normal lung cells and NSCLC cells were also analyzed. In the presence of TGF-β, we transfected the miRNA mimics or inhibitor into NSCLC cells to investigate the role of the significantly altered miRNAs in cell migration and invasion and in the process of EMT.

RESULTS

MiR-330-3p was significantly up-regulated in NSCLC cell lines and tissues and miRNA- 205 was significantly down-regulated in NSCLC cell lines and NSCLC tissues. Transfected miRNA-205 mimics or miRMA-330-3p inhibitor inhibited the migration and invasion of NCIH1975 cell and restrained TGF-β-induced EMT in NSCLC cells.

CONCLUSION

miRNA-330-3p and miRNA-205 changed the most in the process of canceration in NSCLC. Furthermore, miR-330-3p promoted cell invasion and metastasis in NSCLC probably by promoting EMT and miR-205 could restrain NSCLC likely by suppressing EMT.

Prospective randomized comparison of early versus newer-generation vertebral access devices for kyphoplasty

INTRODUCTION

Kyphoplasty is an established method of treating osteoporotic vertebral body compression fractures. In recent years, several techniques to enhance the efficiency and outcomes of this surgery have been developed and implemented in clinical practice. In the present study, we assess the impact of two new access instruments on overall operation time and the administered dose area product in comparison with the standard access instrument used in our clinical practice. The two newer comparator devices have been designed with the intention of streamlining intraoperative workflow by omitting several procedural steps.

MATERIALS AND METHODS

This was a single-center prospective randomized trial investigating three distinct access instruments compatible with the Joline Allevo balloon catheter system. Specifically, two newer access devices marketed as being able to enhance surgical workflow (Joline RapidIntro Vertebra Access Device with a trocar tip and Joline SpeedTrack Vertebra Introducer Device with a short, tapered tip) were compared with the older, established Joline Vertebra Access Device from the same firm. Consecutive eligible and consenting patients scheduled to undergo kyphoplasty for osteoporotic vertebral compression fracture refractory to conservative, medical treatment during the period May 2012-August 2015 were randomized to receive surgery using one of the three devices. Besides the use of the trial instruments, all other preoperative, intraoperative and postoperative care was delivered according to standard practice.

RESULTS

91 kyphoplasties were performed on 65 unique patients during the study period. The median operation time across the three groups was 29 min (IQR 22.5-35.5) with a median irradiation time of 2.3 min (IQR 1.2-3.4). The median patient age was 74 years (IQR 66-80). The groups did not significantly differ in terms of age (p = 0.878), sex (p = 0.37), T score (p = 0.718), BMI (p = 0.285) or the applied volume of cement (p = 0.792). There was no significant difference between the treatment groups with respect to surgical duration (p = 0.157) or dose area product (p = 0.913).

CONCLUSIONS

Although use of the two newer-generation access instruments were designed to involve fewer unique steps per operation, their use was not associated with reduction in surgical duration, irradiation time or dose area product administered compared with the older, established vertebral access device. Care should be taken to evaluate the impact of new instruments on key surgery-related parameters such as surgical duration and radiation exposure and claims made about new instruments should be assessed a structured fashion.

A highly efficient and faithful MDS patient-derived xenotransplantation model for pre-clinical studies

Comprehensive preclinical studies of Myelodysplastic Syndromes (MDS) have been elusive due to limited ability of MDS stem cells to engraft current immunodeficient murine hosts. Here we report a MDS patient-derived xenotransplantation model in cytokine-humanized immunodeficient “MISTRG” mice that provides efficient and faithful disease representation across all MDS subtypes. MISTRG MDS patient-derived xenografts (PDX) reproduce patients’ dysplastic morphology with multi-lineage representation, including erythro- and megakaryopoiesis. MISTRG MDS-PDX replicate the original sample’s genetic complexity and can be propagated via serial transplantation. MISTRG MDS-PDX demonstrate the cytotoxic and differentiation potential of targeted therapeutics providing superior readouts of drug mechanism of action and therapeutic efficacy. Physiologic humanization of the hematopoietic stem cell niche proves critical to MDS stem cell propagation and function in vivo. The MISTRG MDS-PDX model opens novel avenues of research and long-awaited opportunities in MDS research.

Myelodyplastic hematopoietic stem cells (MDS HSC) have eluded in vivo modeling. Here the authors present a highly efficient MDS patient-derived xenotransplantation model in cytokine-humanized mice with replication of the donors’ genetic complexity and myeloid, erythroid, and megakaryocytic lineage dysplasia.

Radiation exposure to the surgeon during minimally invasive spine procedures is directly estimated by patient dose

PURPOSE

Radiation exposure is a necessary component of minimally invasive spine procedures to augment limited visualization of anatomy. The surgeon's exposure to ionizing radiation is not easily recognizable without a digital dosimeter-something few surgeons have access to. The aim of this study was to identify an easy alternative method that uses the available radiation dose data from the C-arm to accurately predict physician exposure.

METHODS

The senior surgeon wore a digital dosimeter during all minimally invasive spine fusion procedures performed over a 12-month period. Patient demographics, procedure information, and radiation exposure throughout the procedure were recorded.

RESULTS

Fifty-five minimally invasive spine fusions utilizing 330 percutaneous screws were included. Average radiation dose was 0.46 Rad/screw to the patient. Average radiation exposure to the surgeon was 1.06 ± 0.71 μSv/screw, with a strong positive correlation (r = 0.77) to patient dose. The coefficient of determination (r²) was 0.5928, meaning almost two-thirds of the variability in radiation exposure to the surgeon is explained by radiation exposure to the patient.

CONCLUSIONS

Intra-operative radiation exposure to the patient, which is easily identifiable as a continuously updated fluoroscopic monitor, is a reliable predictor of radiation exposure to the surgeon during percutaneous screw placement in minimally invasive spinal fusion surgery and therefore can provide an estimate of exposure without the use of a dosimeter. With this, a surgeon can better understand the magnitude of their exposure on a case-by-case basis rather than on a quarterly basis, or more likely, not at all. These slides can be retrieved under Electronic Supplementary Material.

Percutaneous pedicle screw placement under single dimensional fluoroscopy with a designed pedicle finder-a technical note and case series

BACKGROUND CONTEXT

Minimally invasive spine surgery has become increasingly popular in clinical practice, and it offers patients the potential benefits of reduced blood loss, wound pain, and infection risk, and it also diminishes the loss of working time and length of hospital stay. However, surgeons require more intraoperative fluoroscopy and ionizing radiation exposure during minimally invasive spine surgery for localization, especially for guidance in instrumentation placement. In addition, computer navigation is not accessible in some facility-limited institutions.

PURPOSE

This study aimed to demonstrate a method for percutaneous screws placement using only the anterior-posterior (AP) trajectory of intraoperative fluoroscopy.

STUDY DESIGN

A technical report (a retrospective and prospective case series) was carried out.

PATIENT SAMPLE

Patients who received posterior fixation with percutaneous pedicle screws for thoracolumbar degenerative disease or trauma comprised the patient sample.

METHOD

We retrospectively reviewed the charts of consecutive 670 patients who received 4,072 pedicle screws between December 2010 and August 2015. Another case series study was conducted prospectively in three additional hospitals, and 88 consecutive patients with 413 pedicle screws were enrolled from February 2014 to July 2016. The fluoroscopy shot number and radiation dose were recorded. In the prospective study, 78 patients with 371 screws received computed tomography at 3 months postoperatively to evaluate the fusion condition and screw positions.

RESULTS

In the retrospective series, the placement of a percutaneous screw required 5.1 shots (2-14, standard deviation [SD]=2.366) of AP fluoroscopy. One screw was revised because of a medialwall breach of the pedicle. In the prospective series, 5.8 shots (2-16, SD=2.669) were required forone percutaneous pedicle screw placement. There were two screws with a Grade 1 breach (8.6%), both at the lateral wall of the pedicle, out of 23 screws placed at the thoracic spine at T9-T12. Forthe lumbar and sacral areas, there were 15 Grade 1 breaches (4.3%), 1 Grade 2 breach (0.3%), and 1 Grade 3 breach (0.3%). No revision surgery was necessary.

CONCLUSION

This method avoids lateral shots of fluoroscopy during screw placement and thus decreases the operation time and exposes surgeons to less radiation. At the same time, compared with the computer-navigated procedure, it is less facility-demanding, and provides satisfactory reliability and accuracy.

Ibrutinib Treatment of Mantle Cell Lymphoma Relapsing at Central Nervous System: A Case Report and Literature Review

Mantle cell lymphoma (MCL) accounts for about 5% of all lymphomas. Its clinical and histological features are heterogeneous. After a frequently good initial response, the disease generally and repeatedly relapses and finally the outcome is poor. Particularly severe is the prognosis of the rare occurrence of CNSi (Central Nervous System involvement). Ibrutinib, an oral inhibitor of Bruton tyrosine kinase (BTK), has shown strong activity in relapsing patients with Chronic Lymphocytic Leukemia (CLL) and MCL. Few reports are available about treatment with ibrutinib of patients presenting CNSi by lymphoproliferative diseases (LPD). In all of them, ibrutinib, at the dosage between 420 and 560 mg/day, showed an impressive effectiveness. Here we describe a case of MCL with CNS relapse showing an excellent response to ibrutinib administered at the unusual dose of 280 mg/day because of concomitant treatment of cardiological disease.

miR‑181b‑5p mediates TGF‑β1-induced epithelial-to-mesenchymal transition in non-small cell lung cancer stem-like cells derived from lung adenocarcinoma A549 cells

The ability of non-small cell lung cancer (NSCLC) cells to invade and metastasize is associated with epithelial-to-mesenchymal transition (EMT). The process of EMT is, at least in part, regulated by microRNAs. However, it is unknown whether microRNAs regulate EMT in cancer stem-like cells (CSLCs), or which microRNAs are involved. In the present study, we compared microRNA expression in A549 cells, TGF-β1-treated A549 cells, CSLCs characterized by the CD133⁺/CD326⁺ phenotype, and TGF-β1-treated CSLCs. We found that miR-181b-5p expression was upregulated by TGF-β1. Moreover, the overexpression of the miR-181b-5p in A549 cells and CD133⁺/CD326⁺ cells resulted in the down-regulation of the E-cadherin and increased invasion and metastasis in vitro and in vivo. Accordingly, the knockdown of miR-181b-5p partially restored E-cadherin expression. These results suggest that miR-181b-5p regulates TGF-β1-induced EMT by targeting E-cadherin not only in normal A549 cells but also in CD133⁺/CD326⁺ cells which have characteristics of CSLCs. Thus, miR-181b-5p represents a new therapeutic target in NSCLC.

Distribution and features of hematological malignancies in Eastern Morocco: a retrospective multicenter study over 5 years

Background

Hematological malignancies (HM) are a public health problem. The pattern and distribution of diagnosed hematological cancers vary depending on age, sex, geography, and ethnicity suggesting the involvement of genetic and environmental factors for the development of these diseases. To our knowledge, there is no published report on HM in the case of Eastern Morocco. In this report we present for the first time the overall pattern of HM for this region.

Methods

Retrospective descriptive study of patients diagnosed with HM between January 2008 and December 2012 in three centres in Eastern Morocco providing cancer diagnosis, treatment or palliative care services. The FAB (French-American-British) classification system has been taken into account in the analysis of myeloid and lymphoid neoplasms.

Results

In this study, a total of 660 cases of HM were registered between January 2008 and December 2012. Overall, 6075 cases of cancers all sites combined were registered during this study period, indicating that HM account for around 10.9 % (660/6075) of all cancers recorded. Among the 660 registered cases of HM, 53 % were males and 47 % were females, with a male to female ratio of 1.1. Thus, overall, men are slightly more affected with HM than women. By contrast, a female predominance was observed in the case of Hodgkin’s lymphoma (HL), myeloproliferative neoplasms (MPN), acute myeloid leukemia (AML) and the myelodysplastic syndrome (MDS). HM occur at a relatively young age, with an overall median age at diagnosis of 54 years. Non-Hodgkin’s lymphoma (NHL) was the most common HM accounting for 29.7 % of all HM, followed by HL, MPN, multiple myelomas (MM), chronic lymphocytic leukemia (CLL), AML, MDS, acute lymphoblastic leukemia (ALL), and Waldenström macroglobulinemia (WM). The majority of HM cases have been observed among patients aged 60 years and over (40.4 % of HM). Among this age group, NHL was the most common HM. In adolescents, HL was the most frequent HM.

Conclusions

This study provided for the first time the pattern and distribution of HM in Eastern Morocco. Our findings justify the need to establish a regional cancer registry as a first step in blood cancer control in Eastern Morocco.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2205-5) contains supplementary material, which is available to authorized users.

Effects of arsenic disulfide on proliferation, cytokine production, and frequencies of CD4(+), CD8(+), and regulatory T cells in mitogen-activated human peripheral blood mononuclear cells

Influence of arsenic disulfide (As2S2) on human immune cells has little been investigated. Effects of As2S2 on proliferation, cytokine production, and frequencies of CD4(+) T, CD8(+) T and CD4(+)CD25(+)Foxp3(+) regulatory T cells in mitogen-activated human peripheral blood mononuclear cells were examined. Anti-proliferative effects of As2S2 on peripheral blood mononuclear cells activated by T-cell mitogen were assessed by a colorimetric assay. Cytokine concentrations in the culture medium were measured with beads-array procedures followed by flow cytometry. CD4(+) T cells, CD8(+) T cells and CD4(+)CD25(+)Foxp3(+) regulatory T cells were stained with fluorescence-labeled specific antibodies followed by flow cytometry analysis. As2S2 at 1-10μM significantly suppressed mitogen-activated proliferation of peripheral blood mononuclear cells (p<0.05). As2S2 at 10μM inhibited production of IL-6, -10, -17A, tumor necrosis factor-α, and interferon-γ from the activated peripheral blood mononuclear cells, though the effects were not statistically significant. As2S2 at 10μM significantly suppressed the frequencies of CD4(+) T and CD8(+) T cells (p<0.05), whereas significantly enhanced the frequency of CD4(+)CD25(+)Foxp3(+) regulatory T cells (p<0.05). The data suggest that As2S2 attenuates T cell-mediated immunity by not only suppressing the proliferation of T cells and cytokine release but also increasing the frequency of regulatory T cells. T cell-mediated autoimmunity contributes to bone marrow failure in myelodysplastic syndrome (MDS), and thus the above As2S2 effects are beneficial for the treatment of MDS patients.

Overexpression of miR-125a in myelodysplastic syndrome CD34+ cells modulates NF-κB activation and enhances erythroid differentiation arrest

Myelodysplastic syndromes (MDS) are characterized by impaired proliferation and differentiation of hematopoietic stem cells. The participation of toll-like receptor (TLR)-mediated signaling in MDS is well documented. Increased TLR signaling leads to the constitutive activation of NF-κB, which mediates inflammation, cell proliferation and apoptosis. In addition, the TLR pathway induces the expression of miRNAs which participate in the fine-tuning of the inflammatory response. miRNAs also regulate other biological processes, including hematopoiesis. miR-125a and miR-125b are known modulators of hematopoiesis and are abnormally expressed in several hematologic malignancies. However, little is known about their role in MDS. NF-κB-activating ability has been described for both miRNAs. We studied the role of miR-125a/miR-125b in MDS and their relationship with TLR signaling and hematopoietic differentiation. Our results indicate that miR-125a is significantly overexpressed in MDS patients and correlates negatively with patient survival. Expression of miR-99b, which is clustered with miR-125a, is also directly correlated with prognosis of MDS. Both miR-125a and miR-99b activated NF-κB in vitro; however, we observed a negative correlation between miR-99b expression and the levels of TLR2, TLR7 and two downstream genes, suggesting that NF-κB activation by the miRNA cluster occurs in the absence of TLR signaling. We also show that TLR7 is negatively correlated with patient survival in MDS. In addition, our data suggest that miR-125a may act as an NF-κB inhibitor upon TLR stimulation. These results indicate that miR-125a is involved in the fine-tuning of NF-κB activity and that its effects may depend on the status of the TLR pathway. Furthermore, we observed that miR-125a inhibits erythroid differentiation in leukemia and MDS cell lines. Therefore, this miRNA could serve as a prognostic marker and a potential therapeutic target in MDS.

Myelodysplastic Syndrome with 6q Deletion as the Sole Chromosome Abnormality in an Iranian Patient: A Case Report with Review of Literature

BACKGROUND

The myelodysplastic syndrome (MDS) is a highly heterogenous disorder and karyotype analysis is helpful for diagnostic and prognostic estimation. Deletion in long arm chromosome 6 (6q del) as a sole abnormality is a rare event in MDS. This is the first case report of del (6q) as the only observed diagnostic change in Iran. We also reviewed the literature of this cytogenetic lesion.