The human myeloma cell line LP-1: a versatile model in which to study early plasma-cell differentiation and c-myc activation

The characteristics of a human cell line (LP-1) derived from the peripheral blood of a patient with IgG-lambda myeloma in leukemic transformation are described. The cells resemble immature plasma cells in that they exhibit a membrane phenotype that is intermediate between late B lymphocytes and plasma cells, even though they secrete IgG- lambda chains. Treatment of LP-1 cells with 12–0 tetradecanoylphorbol- 13-acetate (TPA) or pokeweek mitogen (PWM) induces the appearance of surface markers and ultrastructural features typical of mature plasma cells but does not affect their proliferative activity. Molecular analysis of the cell line showed an increased expression of the c-myc protooncogene and the presence of abnormally sized transcripts. Conventional cytogenetics and pulsed-field gel electrophoresis showed no structural rearrangements of the c-myc gene, suggesting that the abnormal c-myc expression may be due to point mutations or small deletions within the gene. The LP-1 cell line is a useful model in which to study the process of B-cell maturation; such study may lead to the uncovering of unusual mechanisms of c-myc activation. Furthermore, the LP-1 cell is a potential partner in the generation of human hybridomas.

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The human myeloma cell line LP-1: a versatile model in which to study early plasma-cell differentiation and c-myc activation

Blood ◽

10.1182/blood.v73.4.1020.1020 ◽

1989 ◽

Vol 73 (4) ◽

pp. 1020-1027 ◽

Cited By ~ 49

Author(s):

L Pegoraro ◽

F Malavasi ◽

G Bellone ◽

M Massaia ◽

M Boccadoro ◽

...

Keyword(s):

Cell Line ◽

Plasma Cells ◽

Point Mutations ◽

Myeloma Cell ◽

Human Cell Line ◽

B Cell Maturation ◽

Potential Partner ◽

Human Myeloma Cell Line ◽

Myc Gene ◽

Conventional Cytogenetics

Abstract The characteristics of a human cell line (LP-1) derived from the peripheral blood of a patient with IgG-lambda myeloma in leukemic transformation are described. The cells resemble immature plasma cells in that they exhibit a membrane phenotype that is intermediate between late B lymphocytes and plasma cells, even though they secrete IgG- lambda chains. Treatment of LP-1 cells with 12–0 tetradecanoylphorbol- 13-acetate (TPA) or pokeweek mitogen (PWM) induces the appearance of surface markers and ultrastructural features typical of mature plasma cells but does not affect their proliferative activity. Molecular analysis of the cell line showed an increased expression of the c-myc protooncogene and the presence of abnormally sized transcripts. Conventional cytogenetics and pulsed-field gel electrophoresis showed no structural rearrangements of the c-myc gene, suggesting that the abnormal c-myc expression may be due to point mutations or small deletions within the gene. The LP-1 cell line is a useful model in which to study the process of B-cell maturation; such study may lead to the uncovering of unusual mechanisms of c-myc activation. Furthermore, the LP-1 cell is a potential partner in the generation of human hybridomas.

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Heterogeneous expression of a novel MPC-1 antigen on myeloma cells: possible involvement of MPC-1 antigen in the adhesion of mature myeloma cells to bone marrow stromal cells

Blood ◽

10.1182/blood.v82.12.3721.3721 ◽

1993 ◽

Vol 82 (12) ◽

pp. 3721-3729 ◽

Cited By ~ 31

Author(s):

N Huang ◽

MM Kawano ◽

H Harada ◽

Y Harada ◽

A Sakai ◽

...

Keyword(s):

Bone Marrow ◽

B Cells ◽

Cell Line ◽

Bone Marrow Stromal Cells ◽

Plasma Cells ◽

Myeloma Cell ◽

Myeloma Cell Line ◽

Myeloma Cells ◽

Human Myeloma Cell Line ◽

Heterogeneous Expression

Abstract Recent immunophenotypic analysis has shown that the heterogeneous expression of the adhesion molecule VLA-5 classifies myeloma cells into VLA-5+ mature and VLA-5- immature subpopulations. To further clarify the two myeloma subpopulations, we generated a monoclonal antibody, MPC- 1, by immunizing mice with an adherent human myeloma cell line, KMS-5. The MPC-1 antibody recognized a 48-Kd surface antigen on KMS-5 but not on U-266, a nonadherent human myeloma cell line. Specificity characterization showed that MPC-1 antigen was expressed on mature myeloma cells, normal plasma cells, and mature B cells, whereas pre-B cells and germinal center B cells lacked its expression. Monocytes and a human bone marrow stromal cell line, KM102, also expressed this antigen. Two subclones of MPC-1+ VLA-5+ (KMS-5Ad) and MPC-1-VLA-5+ (KMS- 5NAd) were separated from the KMS-5 cell line. The KMS-5NAd adhered to KM102 more tightly than did the KMS-5NAd, and the U-266 (MPC-1-VLA-5-) displayed almost no adherence to the KM102. The adhesion of the KMS-5Ad was partially inhibited by the MPC-1 antibody. These results, taken together, suggest that the MPC-1 antigen serves as a differentiation marker for B-lineage cells, including plasma cells, and may function as an adhesion molecule involved in the interaction of mature myeloma cells with bone marrow stromal cells.

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Expression of the chemokine receptor CCR1 promotes the dissemination of multiple myeloma plasma cells in vivo

Haematologica ◽

10.3324/haematol.2020.253526 ◽

2020 ◽

pp. 0-0 ◽

Cited By ~ 1

Author(s):

Mara N. Zeissig ◽

Duncan R. Hewett ◽

Vasilios Panagopoulos ◽

Krzysztof M. Mrozik ◽

L. Bik To ◽

...

Keyword(s):

Multiple Myeloma ◽

Cell Line ◽

Plasma Cells ◽

Prognostic Indicator ◽

Myeloma Cell ◽

Nsg Mice ◽

Human Myeloma Cell Line ◽

Chemokine Cxcl12 ◽

Rpmi 8226

Multiple myeloma (MM) disease progression is dependent on the ability of MM plasma cells (PCs) to egress from the bone marrow (BM), enter the circulation and disseminate to distal BM sites. Expression of the chemokine CXCL12 by BM stromal cells is crucial for MM PC retention within the BM. However, the mechanisms which overcome CXCL12-mediated retention to enable dissemination are poorly understood. We have previously identified that treatment with the CCR1 ligand CCL3 inhibits the response to CXCL12 in MM cell lines, suggesting that CCL3/CCR1 signalling may enable egress of MM PC from the BM. Here, we demonstrated that CCR1 expression was an independent prognostic indicator in newly diagnosed MM patients. Furthermore, we showed that CCR1 is a crucial driver of dissemination in vivo, with CCR1 expression in the murine MM cell line 5TGM1 being associated with an increased incidence of bone and splenic disseminated tumours in C57BL/KaLwRij mice. Furthermore, we demonstrated that CCR1 knockout in the human myeloma cell line OPM2 resulted in a >95% reduction in circulating MM PC numbers and BM and splenic tumour dissemination following intratibial injection in NSG mice. Therapeutic targeting of CCR1 with the inhibitor CCX9588 significantly reduced OPM2 or RPMI-8226 dissemination in intratibial xenograft models. Collectively, our findings suggest a novel role for CCR1 as a critical driver of BM egress of MM PCs during tumour dissemination. Furthermore, these data suggest that CCR1 may represent a potential therapeutic target for the prevention of MM tumour dissemination.

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Heterogeneous expression of a novel MPC-1 antigen on myeloma cells: possible involvement of MPC-1 antigen in the adhesion of mature myeloma cells to bone marrow stromal cells

Blood ◽

10.1182/blood.v82.12.3721.bloodjournal82123721 ◽

1993 ◽

Vol 82 (12) ◽

pp. 3721-3729 ◽

Cited By ~ 1

Author(s):

N Huang ◽

MM Kawano ◽

H Harada ◽

Y Harada ◽

A Sakai ◽

...

Keyword(s):

Bone Marrow ◽

B Cells ◽

Cell Line ◽

Bone Marrow Stromal Cells ◽

Plasma Cells ◽

Myeloma Cell ◽

Myeloma Cell Line ◽

Myeloma Cells ◽

Human Myeloma Cell Line ◽

Heterogeneous Expression

Recent immunophenotypic analysis has shown that the heterogeneous expression of the adhesion molecule VLA-5 classifies myeloma cells into VLA-5+ mature and VLA-5- immature subpopulations. To further clarify the two myeloma subpopulations, we generated a monoclonal antibody, MPC- 1, by immunizing mice with an adherent human myeloma cell line, KMS-5. The MPC-1 antibody recognized a 48-Kd surface antigen on KMS-5 but not on U-266, a nonadherent human myeloma cell line. Specificity characterization showed that MPC-1 antigen was expressed on mature myeloma cells, normal plasma cells, and mature B cells, whereas pre-B cells and germinal center B cells lacked its expression. Monocytes and a human bone marrow stromal cell line, KM102, also expressed this antigen. Two subclones of MPC-1+ VLA-5+ (KMS-5Ad) and MPC-1-VLA-5+ (KMS- 5NAd) were separated from the KMS-5 cell line. The KMS-5NAd adhered to KM102 more tightly than did the KMS-5NAd, and the U-266 (MPC-1-VLA-5-) displayed almost no adherence to the KM102. The adhesion of the KMS-5Ad was partially inhibited by the MPC-1 antibody. These results, taken together, suggest that the MPC-1 antigen serves as a differentiation marker for B-lineage cells, including plasma cells, and may function as an adhesion molecule involved in the interaction of mature myeloma cells with bone marrow stromal cells.

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Ruxolitinib Regulates the Autophagy Machinery in Multiple Myeloma Cells

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200218105159 ◽

2020 ◽

Vol 20 (18) ◽

pp. 2316-2323 ◽

Cited By ~ 3

Author(s):

Alican Kusoglu ◽

Bakiye G. Bagca ◽

Neslihan P.O. Ay ◽

Guray Saydam ◽

Cigir B. Avci

Keyword(s):

Multiple Myeloma ◽

Cell Line ◽

B Lymphocyte ◽

Plasma Cells ◽

Annexin V ◽

Myeloma Cell ◽

Control Group ◽

Multiple Myeloma Cell ◽

Ic50 Values ◽

Stat Pathway

Background: Ruxolitinib is a selective JAK1/2 inhibitor approved by the FDA for myelofibrosis in 2014 and nowadays, comprehensive investigations on the potential of the agent as a targeted therapy for haematological malignancies are on the rise. In multiple myeloma which is a cancer of plasma cells, the Interleukin- 6/JAK/STAT pathway is emerging as a therapeutic target since the overactivation of the pathway is associated with poor prognosis. Objective: In this study, our purpose was to discover the potential anticancer effects of ruxolitinib in ARH-77 multiple myeloma cell line compared to NCI-BL 2171 human healthy B lymphocyte cell line. Methods: Cytotoxic effects of ruxolitinib in ARH-77 and NCI-BL 2171 cells were determined via WST-1 assay. The autophagy mechanism induced by ruxolitinib measured by detecting autophagosome formation was investigated. Apoptotic effects of ruxolitinib were analyzed with Annexin V-FITC Detection Kit and flow cytometry. We performed RT-qPCR to demonstrate the expression changes of the genes in the IL-6/JAK/STAT pathway in ARH-77 and NCI-BL 2171 cells treated with ruxolitinib. Results: We identified the IC50 values of ruxolitinib for ARH-77 and NCI-BL 2171 as 20.03 and 33.9μM at the 72nd hour, respectively. We showed that ruxolitinib induced autophagosome accumulation by 3.45 and 1.70 folds in ARH-77 and NCI-BL 2171 cells compared to the control group, respectively. Treatment with ruxolitinib decreased the expressions of IL-6, IL-18, JAK2, TYK2, and AKT genes, which play significant roles in MM pathogenesis. Conclusion: All in all, ruxolitinib is a promising agent for the regulation of the IL-6/JAK/STAT pathway and interferes with the autophagy mechanism in MM.

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Establishment and characterization of a human plasma cell myeloma culture having a rearranged cellular myc proto-oncogene

Blood ◽

10.1182/blood.v67.6.1542.bloodjournal6761542 ◽

1986 ◽

Vol 67 (6) ◽

pp. 1542-1549 ◽

Cited By ~ 1

Author(s):

AF Gazdar ◽

HK Oie ◽

IR Kirsch ◽

GF Hollis

Keyword(s):

Cell Line ◽

Human Plasma ◽

Plasma Cell ◽

Plasma Cells ◽

Cultured Cells ◽

Human Cell Line ◽

Defined Medium ◽

Chromosome 8 ◽

Nuclear Antigen ◽

Secretory Cells

Using a serum-free defined medium, we have established a human cell line, NCI-H929, from a malignant effusion occurring in a patient with IgAk myeloma. The cultured cells have the morphologic, ultrastructural, biochemical, immunologic, and cytochemical features of plasma cells. The cells have rearranged alpha and kappa genes and synthesize and secrete high amounts of IgAk (greater than 80 micrograms/10(6) cells per 24 hours). The cells express surface immunoglobulin (alpha and kappa), the plasma cell antigen PCA-1, the transferrin receptor (T9) and T10 but lack antigens associated with earlier stages of B cell development (HLA-DR, B1, B2, B4, CALLA), as well as other leukocyte- macrophage antigens and Epstein-Barr virus (EBV) nuclear antigen. Although molecular studies confirm that both the tumor and cultured cells are derived from the same clone of malignant B cells, the tumor cells were predominantly near-diploid, whereas the cultured cells are predominantly near-tetraploid with six copies of chromosome 8, four to six of which have an 8q + abnormality. However, both the tumor and the cultured cells have a rearrangement of the cellular c-myc proto- oncogene (located at 8q24) and express c-myc RNA. Although a modest number of human “plasmacytoid” cell lines have been established, most are lymphoblastoid lines lacking plasma cell features, while others appear to be early secretory cells. In contrast, NCI-H929 is a differentiated, highly secretory human plasma cell line.

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Enforced CD19 Expression Leads to Growth Inhibition and Reduced Tumorigenicity

Blood ◽

10.1182/blood.v94.10.3551.422k08_3551_3558 ◽

1999 ◽

Vol 94 (10) ◽

pp. 3551-3558 ◽

Cited By ~ 33

Author(s):

Maged S. Mahmoud ◽

Ryuichi Fujii ◽

Hideaki Ishikawa ◽

Michio M. Kawano

Keyword(s):

Growth Inhibition ◽

Cell Line ◽

Myeloma Cell ◽

Inhibitory Effect ◽

Myeloma Cell Line ◽

Growth Inhibitory Effect ◽

Myeloma Cells ◽

Growth Inhibitory ◽

Human Myeloma Cell Line

In multiple myeloma (MM), the cell surface protein, CD19, is specifically lost while it continues to be expressed on normal plasma cells. To examine the biological significance of loss of CD19 in human myeloma, we have generated CD19 transfectants of a tumorigenic human myeloma cell line (KMS-5). The CD19 transfectants showed slower growth rate in vitro than that of control transfectants. They also showed a lower capability for colony formation as evaluated by anchorage-independent growth in soft agar assay. The CD19 transfectants also had reduced tumorigenicity in vivo when subcutaneously implanted into severe combined immunodeficiency (SCID)-human interleukin-6 (hIL-6) transgenic mice. The growth-inhibitory effect was CD19-specific and probably due to CD19 signaling because this effect was not observed in cells transfected with a truncated form of CD19 that lacks the cytoplasmic signaling domain. The in vitro growth-inhibitory effect was confirmed in a nontumorigenic human myeloma cell line (U-266). However, introduction of the CD19 gene into a human erythroleukemia cell line (K-562) also induced growth inhibition, suggesting that this effect is CD19-specific, but not restricted to myeloma cells. These data suggest that the specific and generalized loss of CD19 in human myeloma cells could be an important factor contributing to the proliferation of the malignant plasma cell clones in this disease.

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