CD69 Expression Predicts Favorable Outcome in Multiple Myeloma Patients Treated with VTD

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1768-1768
Author(s):  
Gabriele Buda ◽  
Giovanni Carulli ◽  
Enrico Orciuolo ◽  
Paola Sammuri ◽  
Sara Galimberti ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Plasma Cells ◽  
Conflicts Of Interest ◽  
Clinical Status ◽  
Prognostic Impact ◽  
Clinical Report ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Cd69 Expression

Abstract Multiple myeloma is an incurable disease characterized by proliferation of clonal malignant plasma cells (PC). Molecular characterization of malignant plasma cells is increasingly important for diagnostic and therapeutic stratification but the clinical and prognostic value of immunophenotyping in MM remains questionable. We have analyzed the prognostic impact of a relatively new marker as CD69. CD69 is a type II membrane protein. T cells express CD69 rapidly upon stimulation of the T-cell receptor (TCR), which is why CD69 has been mostly regarded as an activation marker. The precise role of CD69 in immunity has not been determined because its ligand is unknown, but an emerging role of CD69 in Multiple Myeloma (MM) has been postulated. Previous laboratoristic data, using tumor lines derived from murine model with genotypic and immunophenotypic features of resistance to bortezomib, showed that as the neoplastic plasma cells (PC) develop bortezomib resistance, they have a germinal center B cell like immunophenotype, including decreased to absent expression of CD69. Interestingly the activation antigen CD69 associates with and inhibits the function of Sphingosine 1-phosphate (S1P). S1P is a bioactive lysophospholipid which is known to induce diverse cellular responses through at least five G-protein-coupled receptors on various cell types. Other data showed that MM cells express the S1P receptors, S1P1, S1P2 and S1P3. Furthermore, S1P protects MM cells against dexametason-induced apoptosis. Importantly, S1P upregulates Mcl-1 expression in a time and concentration-dependent manner in human MM cell lines. In a previous abstract, we described for the first time in a clinical report, the CD69 expression on pathological PCs of MM patients. Our preliminary data also suggested an intriguing role of CD69 in patients treated with chemotherapy in different stages of disease. In this study, we report a larger setting of 97 patients where we confirmed the expression of CD 69 in 48 of them (49%) (see table I). Immunophenotyping was carried out by a 6-color method, using a FacsCanto II cytometer and the FacsDiva software. PCs were identified as CD138+/CD38+ events after an initial gate which included events with low SSC in the CD45/SSC cytogram. The MoAb panel also included CD19, CD20, CD117, CD56, cytoplasmic light chains K and Lambda. PerCP-Cy5.5-conjugated CD69 was evaluated on phenotypically abnormal plasma cells (i.e. CD19-, CD45- or dim), which were resulted to be clonally restricted. Results were considered positive when the percentage of positive cells was > 20%. After an induction regimen of treatment with four cycles of VDT (bortezomib, dexametasone, thalidomide), 69 patients were evaluable. 40/69 (65%) of patients obtained at least of a very good partial response or better (Responding pts). In this subgroup of patients 30/45 (66.6%) showed the expression of CD 69. On the contrary only in a little part of partial or less responding patients (NR pts) 9/24 (37.5%) CD69 was detected (see table II) (p=0.02 using a chi squared test and p=0.019 using a Fisher's exact test). Data on cytogenetic abnormalities, including del(13q), t(4;14) and del(17p), detected by fluorescence in situ hybridization, were available in >90% of patients. Clinical data were available in all patients and CD69 maintained its association with different response, independently of other prognostic variables. In conclusion CD69 is often expressed in PCM cases, and the expression of this marker is useful to reveal poor prognostic categories and delineate a risk stratification. This molecule could represent an emerging clinical factor to identify different outcomes in patients affected by MM and treated with the modern drugs. Table I Pts Characteristics Total CD69+ 97 48/97 Sex Male 51(52%) Female 46(48%) Clinical status MM non evaluableMM after VTD 28/9769/97 in VGPR/CR 45/69 in PR/SD/PD 24/69 Table II Pts treated with VTD Responding pts NRpts 45 24 CD69+ 39/69 30/45 9/24 CD69- 30/69 15/45 15/24 Disclosures No relevant conflicts of interest to declare.

CD69, a New Potential Clinical Marker in Multiple Myeloma

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 2027-2027 ◽  
Author(s):  
Gabriele Buda ◽  
Giovanni Carulli ◽  
Enrico Orciuolo ◽  
Paola Sammuri ◽  
Daniele Campa ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Plasma Cells ◽  
Cell Phenotype ◽  
Clinical Report ◽  
Dependent Manner ◽  
Cd69 Expression ◽  
Group A ◽  
Group B

Abstract CD69 is a type II membrane protein. T cells express CD69 rapidly upon stimulation of the T-cell receptor (TCR), which is why CD69 has been mostly regarded as an activation marker. The precise role of CD69 in immunity has not been determined because its ligand is unknown, but an emerging role of CD69 in Multiple Myeloma (MM) has been postulated. Previous data, using tumor lines derived from murine model with genotypic and immunophenotypic features of resistance to bortezomib, showed that as the neoplastic plasma cells (PC) develop bortezomib resistance, they have a germinal center B cell like immunophenotype, including decreased to absent expression of CD69. CD69 has not been yet studied in human multiple myeloma, though it has been shown that human chronic lymphocytic lymphoma cells, when induced toward a plasma cell phenotype with tetradecanoyl phorbol acetate (TPA) have increased CD69 expression. Interestingly the activation antigen CD69 associates with and inhibits the function of Sphingosine 1-phosphate (S1P). S1P is a bioactive lysophospholipid which is known to induce diverse cellular responses through at least five G-protein-coupled receptors on various cell types. Other data showed that MM cells express the S1P receptors, S1P1, S1P2 and S1P3. Furthermore, S1P protects MM cells against dexametason-induced apoptosis. Importantly, S1P upregulates Mcl-1 expression in a time and concentration-dependent manner in human MM cell lines. Therefore, we analyzed the CD69 expression on pathological PCs, from bone marrow samples of 43 patients, by flow cytometry with two aims: to evaluate the real expression of CD69 on pathological PCs and to determine the clinico-pathological significance of this molecule. Immunophenotyping was carried out by a 6-color method, using a FacsCanto II cytometer and the FacsDiva software. PCs were identified as CD138+/CD38+ events after an initial gate which included events with low SSC in the CD45/SSC cytogram. The MoAb panel also included CD19, CD20, CD117, CD56, cytoplasmic light chains K and Lambda. PerCP-Cy5.5-conjugated CD69 was evaluated on phenotypically abnormal plasma cells (i.e. CD19-, CD45- or dim), which were resulted to be clonally restricted. Results were considered positive when the percentage of positive cells was > 20%. 22 of 43 pts (see table I, group A) were MM resistant/refractory to at least two different chemotherapy regimens (including bortezomib in all patients). 21 patients (table I, group B) were smouldering multiple myeloma (SMM) or MM in at least very good partial response (VGPR) after first line treatment. CD69 was detected on bone marrow PCs in 19 of the 43 patients evaluated (44%). Of the 19 patients with CD69+ (see table II) only 6 (27%) were in the group of refractory/resistant MM, while the majority of these advanced patients, 16/22 (73%), had an absent expression of CD69. On the contrary in the group of SMM/VGPR/CR MM 13 patients (62%) were CD69+ (p=0.04, using a Chi squared test with Yates correction). At the best of our Knowledge this is the first clinical report that confirms CD69 expression on pathological PCs of MM patients. Our preliminary data also suggest an intriguing role of CD69, this molecule could represent an emerging clinical factor to identify different outcomes in patients affected by MM and treated with the modern drugs. Table IPts CharacteristicsGroup AGroup B2221SexMale8(36%)11(52%)Female14(64%)10 (48%)Clinical statusSMMMM inVGPR/CR9 (43%)12 (57%)Relapsed/refractory22(100%)Number of Previous Therapy (range)3,5 (2-6)1 (0-1)Previous Bor regimenSMM0MM inVGPR/CR12(100%)Relapsed/refractory22(100%)Previous Lena regimenSMM0MM inVGPR/CR0Relapsed/refractory17(77%) Table II Pts Results Group A Group B 22 21 CD69+ 19/43 (44%) 6 (27%) 13 (62%) CD69-24/43 (56%) 16 (73%) 8 (38%) Disclosures No relevant conflicts of interest to declare.

Anti-Leukemia and Multiple Myeloma Selective Activity of CXCR4 Antagonist 4F-Benzoyl-TN14003 Involves Apoptotic Death Pathway.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3857-3857
Author(s):  
Katia Beider ◽  
Michal Begin ◽  
Michal Abraham ◽  
Hanna Wald ◽  
Ido Weiss ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Death ◽  
Hematological Malignancies ◽  
Conflicts Of Interest ◽  
K562 Cells ◽  
Jurkat Cells ◽  
G1 Arrest ◽  
Dependent Manner ◽  
Hl60 Cells

Abstract Abstract 3857 Poster Board III-793 The chemokine receptor CXCR4 and its ligand CXCL12 are involved in the development and progression of a diverse number of hematological malignancies, including leukemia, lymphoma and multiple myeloma (MM). Binding CXCL12 to CXCR4 activates a variety of intracellular signal transduction pathways and effector molecules that regulate cell chemotaxis, adhesion, survival, apoptosis and proliferation. It was previously shown that CXCR4 signaling can directly induce caspase-independent cell apoptosis through the interaction with the HIV gp120 envelope protein. In the present study we investigated the effect of CXCR4 specific antagonists 4F-benzoyl-TN14003 (T140) and AMD3100 on the survival and proliferation of different human hematological cancer cells. Here, we demonstrate that T140, but not AMD3100, exhibits preferential cytotoxicity towards malignant cells of hematopoietic origin, as compared to primary normal cells or solid prostate and breast tumor cells. The in vitro treatment with T140, but not with AMD3100, significantly decreased the number of viable chronic myeloid leukemia K562 cells, acute T cell leukemia Jurkat cells, acute promyelocytic leukemia NB4 and HL60 cells, and four different MM cell lines (U266, NCI-H929, RPMI8226 and ARH77), demonstrating the highest sensitivity to T140 (p<0.01). Notably, T140 inhibited the growth of freshly isolated leukemia and MM cells obtained from consenting patients. T140 inhibits the growth of MM and leukemic cells by inducing their apoptotic cell death. The apoptotic changes in the cells were associated with morphological changes, phosphatidylserine externalization, sub-G1 arrest, DNA double-stranded breaks, decrease in mitochondrial membrane potential, release of cytochrome c, and caspase 3 activation. The important role of CXCR4 in T140-mediated cell death was confirmed by demonstrating that CXCR4 over-expression in NB4 and K562 cells increased their sensitivity to T140. Furthermore, pretreatment of NB4 and HL60 cells with AMD3100 abolishes the effect of T140 on these cells, indicating the involvement of CXCR4 in T140-induced apoptosis. Importantly, the combination with novel anti-myeloma agent bortezomib significantly augments anti-myeloma activity of T140. The anti leukemic and MM effect of T140 was confirmed in xenograft in vivo tumor models. Subcutaneous (s.c.) or intra-peritoneal (i.p.) injections of T140 (100 or 300 mcg/mouse) significantly reduced, in a dose-dependent manner, the tumor size in immuno-deficient mice that were previously inoculated s.c. with human acute leukemia cells NB4 or MM cells RPMI8226 (p<0.01). Tumors from animals treated with T140 had smaller sizes and weights, larger necrotic areas and high apoptotic scores. Taken together, these data support the unique anti-cancer effect of T140 in hematological malignancies and indicate the potential therapeutic role of T140 in MM and leukemia patients. Disclosures: No relevant conflicts of interest to declare.

Membrane Lipid Biosynthesis As a Potential Therapeutic Target in Multiple Myeloma

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1836-1836
Author(s):  
Carolyne Bardeleben ◽  
Alan Lichtenstein
Keyword(s):  
Multiple Myeloma ◽  
Er Stress ◽  
Cell Lines ◽  
Cell Apoptosis ◽  
Plasma Cells ◽  
Conflicts Of Interest ◽  
Membrane Lipid ◽  
Dependent Manner ◽  
Kennedy Pathway ◽  
Phosphatidylcholine Synthesis

Abstract Abstract 1836 Phosphatidylcholine (PC) is the most prominent phospholipid in mammalian endoplasmic reticulum (ER) membranes. The rate-limiting step in PC synthesis through the Kennedy pathway is the conversion of phosphocholine + cytidine triphosphate (CTP) to cytidine diphosphocholine, (CDP)-choline, via the enzyme CTP:phosphocholine cytidylyltransferase (CCT) (see figure). Multiple myeloma (MM) cells may be particularly dependent on this biosynthetic reaction because of their high consistent level of ER stress and requirement to continuously replenish ER membranes. Indeed, CCT-null mice have a defect in differentiation of B lymphocytes to plasma cells and deficiencies in Ig synthesis. To test whether this pathway remains critical in survival of malignant MM cells, we exposed MM cell lines to an inhibitor shown to inhibit CCT activity, HexPC. HexPC induced apoptosis in all MM cell lines in a concentration- and time-dependent manner. The addition of lysophosphatidylcholine (LPC), presumably converted to PC independently of the Kennedy pathway, completely rescued MM cell apoptosis. In contrast, similar concentrations of LPC in the same cell lines could not rescue apoptosis induced by bortezomib. An additional intervention to inhibit phosphatidylcholine synthesis, namely inducing pyrimidine starvation, also resulted in MM cell apoptosis and down-regulation of CDP-choline levels. Apoptosis of MM cells induced by HexPC was associated with induction of ER stress as shown by enhanced phosphorylation of IRE1 and eIF-2alpha. This ER stress was also prevented when LPC was added to HexPC although LPC could not prevent similar ER stress induced by bortezomib. These results underscore the importance of this phosphatidylcholine synthesis pathway in MM cells and provide new targets for future therapy. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Role of N6-Methyladenosine (m6A) RNA Modification in Multiple Myeloma

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5601-5601
Author(s):  
Christian Bach ◽  
Magdalena Leffler ◽  
Cindy Flamann ◽  
Jan Kronke ◽  
Dimitrios Mougiakakos ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Lines ◽  
Messenger Rna ◽  
Plasma Cells ◽  
Conflicts Of Interest ◽  
Stop Codon ◽  
Mrna Levels ◽  
Molecular Abnormalities ◽  
Gene Expression Control

Abstract Multiple myeloma (MM) is considered a chronic and incurable disease due to its highly complex and heterogeneous molecular abnormalities. In recent years, integrating proteasome inhibitors and immunomodulatory drugs into MM frontline therapy has significantly improved treatment efficacy with a median overall survival (OS) being prolonged from 3-4 to 7 years. Despite this progress, patients refractory to the aforementioned agent classes display a median OS of only 9 months. Thus, the clinical necessity for developing novel therapeutic alternative approaches is self-evident. Methylation of N6-adenosine (m6A) is known to be important for diverse biological processes including gene expression control, translation of protein, and messenger RNA (mRNA) splicing. m6A regulatory enzymes consist of "writers" METTL3 and METTL14, "readers" YTHDF1 and YTHDF2, and "erasers" FTO and ALKBH5. However, the functions of m6A mRNA modification and the specific role of these enzymes in MM remain unknown. Here we report that METTL3, a key component of the m6A methyltransferase complex, is highly expressed in MM cell lines and in isolated patient's MM cells. In contrast, we found no significant differences in the expression of the m6A demethylases FTO and ALKBH5. Accordingly, compared to plasma cells from healthy donors, global PolyA+ RNA showed a significant increase in m6A content in patient's MM plasma cells. In MM cell lines, global m6A profiling by methylated RNA-immunoprecipitation sequencing revealed m6A peaks near the stop codon in mRNAs of multiple oncogenes including MAF and CCND1. Cross-linking immunoprecipitation showed that METTL3 bound to the m6A peak within MAF and CCND1 mRNA. Depletion of METTL3 by shRNA had little effect on global mRNA levels, but specifically reduced protein levels of c-Maf and Cyclin D1. Moreover, downregulation of METTL3 in several MM cell lines results in cell cycle arrest and apoptosis. Together, these results describe a role for METTL3 in promoting translation of a subset of oncogenes in MM and identify this enzyme as a potential therapeutic target for multiple myeloma. Disclosures No relevant conflicts of interest to declare.

Multiple Myeloma and Microenvironment Formation: The Role of CXCR4/CXCL12 Chemokine Pathway

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2962-2962
Author(s):  
Katia Beider ◽  
Avichai Shimoni ◽  
Odit Gutwein ◽  
Merav Leiba ◽  
Elena Ribakovsky ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Disease Progression ◽  
Stromal Cells ◽  
Neutralizing Antibodies ◽  
Plasma Cells ◽  
Immune Cell ◽  
Conflicts Of Interest ◽  
Cell Surface Expression ◽  
Monocyte Recruitment

Abstract Abstract 2962 Background: Multiple myeloma (MM) is characterized by clonal proliferation of malignant plasma cells (PCs) in the bone marrow (BM) compartment. Interaction of plasma cells with the BM stromal cells (BMSCs) is critical for homing, growth and drug resistance acquisition of the malignant PCs. However, the functional significance of other cellular components of the MM milieu, which includes osteoclasts and immune effector cells, is less clear. Both MM-derived and stromal cell-produced factors, including cytokines and chemokines, are believed to participate in the cross-talk between the MM and stroma leading to disease progression. Aim and Results: We hypothesized an important role for CXCL12 (SDF-1) chemokine and its receptor CXCR4 in MM-stroma interactions and microenvironment formation. We now show that MM cell lines ARH77 and RPMI8226 and primary MM cells may produce high amounts of CXCL12 and co-express CXCR4 receptor. Co-culture of the MM cells with BMSCs significantly up-regulated both CXCR4 cell-surface expression and CXCL12 secretion by the MM cells. Enhanced CXCR4 signaling in the MM cells upon the interaction with BMSCs promoted the survival and proliferation of the cells in an autocrine way. Moreover, the paracrine effect of increased CXCL12 production on immune cell migration was tested. We found, that conditioned medium (CM) produced by MM cells cultured with BMSCs specifically attracted increased numbers of CXCR4-expressing PB CD14+ cells. Furthermore, CXCR4 inhibition, using neutralizing antibodies toward CXCR4, inhibited the MM-induced migration of CD14+ monocytes, suggesting the possible role of CXCR4/CXCL12 axis in monocyte recruitment to the site of the disease. We next examined the functional consequence of MM-macrophage interaction. We saw that PB-generated macrophages induced the proliferation of MM cells, even more effectively than BMSCs. Furthermore, co-culture with macrophages strongly increased the expression of various pro-inflammatory and pro-angiogenic factors by MM cells, including CCL2 (MCP-1), CCL4 (MIP1a), IL-1b, IL-8 and VEGF. Interestingly, expression of IL-10 by MM cells was also up-regulated following the interaction with macrophages, suggesting the possible reciprocal effect of MM-produced factors on macrophage phenotype polarization. Conclusion: Taken together, our findings demonstrate that interaction of MM with BM stromal cells positively regulates the expression of CXCR4 and CXCL12 by MM cells, affecting both MM proliferation and CXCR4-dependent monocyte recruitment. The migrated monocytes may in turn interact with MM cells, support their growth and activate cytokine release, therefore producing favorable pro-inflammatory and pro-angiogenic environment and promoting disease progression. Overall, our data provide the basis for future targeting MM-BMSCs and MM-macrophage interactions with anti-CXCR4 agents as a therapeutic strategy to improve the outcome of patients with MM. Disclosures: No relevant conflicts of interest to declare.

The Chromosomal Abnormalities Del(17p), t(4;14), and +1q21 Predict Progression From Smoldering to Symptomatic Multiple Myeloma

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1806-1806 ◽  
Author(s):  
Kai Neben ◽  
Anna Jauch ◽  
Thomas Hielscher ◽  
Jens Hillengass ◽  
Nicola Lehners ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Risk Score ◽  
Chromosomal Aberrations ◽  
Plasma Cells ◽  
Chromosomal Abnormalities ◽  
Conflicts Of Interest ◽  
Statistical Significance ◽  
Entire Group ◽  
Fish Analysis ◽  
Prognostic Impact

Abstract Abstract 1806 Background: Smoldering Multiple Myeloma (SMM) is a plasma cell disorder defined by the presence of ≥10% plasma cells in bone marrow and/or a monoclonal protein level of ≥3 g/dl in serum without organ damage. The aim of the study was to analyze the prognostic impact of chromosomal aberrations on time to progression (TTP) from SMM to symptomatic MM. Design and Methods: For selection of the patients, we used the same criteria as previously described by Kyle (Kyle et al., NEJM, 2007). We analyzed the prognostic value of 5 chromosomal abnormalities and hyper-/non-hyperdiploidy (HD and NHD, respectively) in a series of 231 patients with SMM by fluorescent in situ hybridization (FISH). Gains of at least 2 of the 3 chromosomes 5, 9, and 15 defined HD status. Results: Interphase-FISH analysis on CD138-enriched plasma cells detected gains of chromosomes 1q21 (29.4%) as well as deletions of chromosomes 13q14 (19.3%) and 17p13 (6.1%). Furthermore, the IgH-translocations t(4;14) and t(11;14) were observed in a frequency of 9.2% and 22.3%, respectively. The presence of t(4;14) was correlated with the serum heavy chain IgA (p<0.001). For the entire group, the median TTP was 4.9 years (95% CI, 3.9 – NA). Of all analyzed chromosomal abnormalities, del(17p13), t(4;14), and +1q21 showed a significant impact on TTP, whereas the presence of t(11;14) and del(13q14) was of no statistical significance. The median TTP for patients with del(17p13) was 2.7 years (vs. 4.9 years without, p=0.019), with t(4;14) 2.9 years (vs. 5.2 years without, p=0.021), and with +1q21 3.7 years (vs. 5.3 years without, p=0.013), respectively. In addition, HD was associated with a statistically shorter median TTP of 3.9 vs. 5.7 years in patients with NHD, respectively (p=0.036). A multivariate analysis identified t(4;14), +1q21, HD, reduction of uninvolved immunoglobulins (no.), and the risk score defined by Kyle et al. as independent factors for adverse outcome. Conclusions: The study shows that the overall risk of progression in SMM is significantly influenced by markers for tumor burden (i.e. Kyle risk score) as well as the presence of the chromosomal aberrations del(17p13), t(4;14), and +1q21. Our findings provide evidence that specific chromosomal aberrations are not only associated with early tumor progression and drug resistance in patients with overt MM but also to drive transition from asymptomatic into symptomatic stage of disease. Disclosures: No relevant conflicts of interest to declare.

scholarly journals 5-Azacitidine Remolds the Methylation Status and Inhibits Growth in Multiple Myeloma

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4817-4817
Author(s):  
Wenming Wang ◽  
Jing Wang ◽  
Mingyi Chen ◽  
Yaoxian Liang ◽  
Zhengqian Li ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Dna Methylation ◽  
Multiple Myeloma ◽  
Cell Lines ◽  
Methylation Level ◽  
Plasma Cells ◽  
Conflicts Of Interest ◽  
Methylation Status ◽  
Dependent Manner ◽  
M Cell

Abstract Multiple myeloma (MM) is a malignant disorder characterized by the proliferation of a single clone of plasma cells derived from B cells. Previous studies have demonstrated that both gene-specific hypermethylation and global hypomethylation characterizes the multiple myeloma epigenome. 5-azacytidine as a DNA methylation inhibitor has therapeutic efficacy in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Nevertheless,the effects of 5-azacytidine on MM remains unclear. We used RT-PCR to detect the expression of PTPL1 and used MS-PCR to determine the methylation status of PTPL1 in MM cell lines and after 5-azacytidine treatment. ELISA-like reaction was used to detect global DNA methylation level. The cytotoxic activity of 5-azacytidine was tested using cell viability and apoptosis assays. Flow cytometry was used to detect cell cycle after 5-azacytidine treatment. Our experiments discovered that the PTPL1 gene was hypermethylated in the U266 and H929 cell lines, and the expression of PTPL1 mRNA could be re-inducible by 5-azacytidine. 5-azacytidine also inhibited the proliferation of multiple myeloma cell lines U266 and H929 in a time- and dose-dependent manner, induced G2/M cell cycle arrest and caspase-dependent apoptosis. But in our study 5-azacytidine increased the methylation level for both cell lines. Our study showed that PTPL1 was epigenetically regulated in MM which can be reversed by 5-azacytidine, and highlights 5-azacytidine is a potential therapeutic candidate for MM, but additional studies are needed to determine the effects of genome-wide methylation changes in MM. Disclosures No relevant conflicts of interest to declare.

scholarly journals Role of Aiolos and Ikaros in the Antitumor and Immunomodulatory Activity of IMiDs in Multiple Myeloma: Better to Lose Than to Find Them

2021 ◽  
Vol 22 (3) ◽  
pp. 1103
Author(s):  
Marco Cippitelli ◽  
Helena Stabile ◽  
Andrea Kosta ◽  
Sara Petillo ◽  
Angela Gismondi ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Plasma Cells ◽  
Immunomodulatory Activity ◽  
Cancer Cell Growth ◽  
Cytotoxic Effects ◽  
Growth And Survival ◽  
Therapeutic Implications ◽  
Development And Differentiation ◽  
Innate Lymphocytes

The Ikaros zing-finger family transcription factors (IKZF TFs) are important regulators of lymphocyte development and differentiation and are also highly expressed in B cell malignancies, including Multiple Myeloma (MM), where they are required for cancer cell growth and survival. Moreover, IKZF TFs negatively control the functional properties of many immune cells. Thus, the targeting of these proteins has relevant therapeutic implications in cancer. Indeed, accumulating evidence demonstrated that downregulation of Ikaros and Aiolos, two members of the IKZF family, in malignant plasma cells as well as in adaptative and innate lymphocytes, is key for the anti-myeloma activity of Immunomodulatory drugs (IMiDs). This review is focused on IKZF TF-related pathways in MM. In particular, we will address how the depletion of IKZF TFs exerts cytotoxic effects on MM cells, by reducing their survival and proliferation, and concomitantly potentiates the antitumor immune response, thus contributing to therapeutic efficacy of IMiDs, a cornerstone in the treatment of this neoplasia.

The P-element-induced silencing effect of KP transposons is dose dependent in Drosophila melanogaster

Genome ◽  
2011 ◽  
Vol 54 (9) ◽  
pp. 752-762 ◽  
Author(s):  
Alireza Sameny ◽  
John Locke
Keyword(s):  
Drosophila Melanogaster ◽  
Critical Role ◽  
Mutagenic Effect ◽  
P Element ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
P Elements ◽  
Single Well ◽  
Dose Dependent

Transposable elements are found in the genomes of all eukaryotes and play a critical role in altering gene expression and genome organization. In Drosophila melanogaster, transposable P elements are responsible for the phenomenon of hybrid dysgenesis. KP elements, a deletion-derivative of the complete P element, can suppress this mutagenic effect. KP elements can also silence the expression of certain other P-element-mediated transgenes in a process called P-element-dependent silencing (PDS), which is thought to involve the recruitment of heterochromatin proteins. To explore the mechanism of this silencing, we have mobilized KP elements to create a series of strains that contain single, well-defined KP insertions that show PDS. To understand the quantitative role of KP elements in PDS, these single inserts were combined in a series of crosses to obtain genotypes with zero, one, or two KP elements, from which we could examine the effect of KP gene dose. The extent of PDS in these genotypes was shown to be dose dependent in a logarithmic rather than linear fashion. A logarithmic dose dependency is consistent with the KP products interacting with heterochromatic proteins in a concentration-dependent manner such that two molecules are needed to induce gene silencing.

Protein kinase C potentiates cAMP-stimulated mouse duodenal mucosal bicarbonate secretion in vitro

2004 ◽  
Vol 286 (5) ◽  
pp. G814-G821 ◽  
Author(s):  
Bi-Guang Tuo ◽  
Jimmy Y. C. Chow ◽  
Kim E. Barrett ◽  
Jon I. Isenberg
Keyword(s):  
Short Circuit ◽  
Short Circuit Current ◽  
Duodenal Mucosa ◽  
Bicarbonate Secretion ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Ussing Chambers ◽  
Duodenal Bicarbonate Secretion

PKC has been shown to regulate epithelial Cl- secretion in a variety of models. However, the role of PKC in duodenal mucosal bicarbonate secretion is less clear. We aimed to investigate the role of PKC in regulation of duodenal mucosal bicarbonate secretion. Bicarbonate secretion by murine duodenal mucosa was examined in vitro in Ussing chambers using a pH-stat technique. PKC isoform expression and activity were assessed by Western blotting and in vitro kinase assays, respectively. PMA (an activator of PKC) alone had no effect on duodenal bicarbonate secretion or short-circuit current ( Isc). When PMA and dibutyryl-cAMP (db-cAMP) were added simultaneously, PMA failed to alter db-cAMP-stimulated duodenal bicarbonate secretion or Isc ( P > 0.05). However, a 1-h preincubation with PMA potentiated db-cAMP-stimulated duodenal bicarbonate secretion and Isc in a concentration-dependent manner (from 10-8 to 10-5M) ( P < 0.05). PMA preincubation had no effects on carbachol- or heat-stable toxin-stimulated bicarbonate secretion. Western blot analysis revealed that PKCα, -γ, -ϵ, -θ, -μ, and -ι/λ were expressed in murine duodenal mucosa. Ro 31–8220 (an inhibitor active against PKCϵ, -α, -β, and -γ), but not Gö 6983 (an inhibitor active against PKCα, -γ, -β, and -δ), reversed the potentiating effect of PMA on db-cAMP-stimulated bicarbonate secretion. PMA also time- and concentration-dependently increased the activity of PKCϵ, an effect that was prevented by Ro 31–8220 but not Gö 6983. These results demonstrate that activation of PKC potentiates cAMP-stimulated duodenal bicarbonate secretion, whereas it does not modify basal secretion. The effect of PKC on cAMP-stimulated bicarbonate secretion is mediated by the PKCϵ isoform.

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