ABSTRACT
Clonal evolution drives tumor progression, dissemination, and relapse in multiple myeloma (MM), with most patients dying of relapsed disease. This multistage process requires tumor cells to enter the circulation, extravasate, and colonize distant bone marrow (BM) sites. Here, we developed a fluorescent or DNA-barcode clone-tracking system on MM PrEDiCT (progression through evolution and dissemination of clonal tumor cells) xenograft mouse model to study clonal behavior within the BM microenvironment. We showed that only the few clones that successfully adapt to the BM microenvironment can enter the circulation and colonize distant BM sites. RNA sequencing of primary and distant-site MM tumor cells revealed a progression signature sequentially activated along human MM progression and significantly associated with overall survival when evaluated against patient data sets. A total of 28 genes were then computationally predicted to be master regulators (MRs) of MM progression. HMGA1 and PA2G4 were validated in vivo using CRISPR-Cas9 in the PrEDiCT model and were shown to be significantly depleted in distant BM sites, indicating their role in MM progression and dissemination. Loss of HMGA1 and PA2G4 also compromised the proliferation, migration, and adhesion abilities of MM cells in vitro. Overall, our model successfully recapitulates key characteristics of human MM disease progression and identified potential new therapeutic targets for MM.
Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Biomarkers, Tumor/metabolism , Disease Models, Animal , Gene Expression Regulation, Neoplastic , HMGA1a Protein/metabolism , Multiple Myeloma/pathology , Neoplasm Recurrence, Local/pathology , RNA-Binding Proteins/metabolism , Adaptor Proteins, Signal Transducing/antagonists & inhibitors , Adaptor Proteins, Signal Transducing/genetics , Animals , Apoptosis , Biomarkers, Tumor/genetics , Bone Marrow/metabolism , Bone Marrow/pathology , CRISPR-Cas Systems , Cell Adhesion , Cell Movement , Cell Proliferation , Clonal Evolution , Disease Progression , Female , HMGA1a Protein/antagonists & inhibitors , HMGA1a Protein/genetics , Humans , Mice , Mice, SCID , Multiple Myeloma/genetics , Multiple Myeloma/metabolism , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/metabolism , Prognosis , RNA-Binding Proteins/antagonists & inhibitors , RNA-Binding Proteins/genetics , Survival Rate , Tumor Cells, CulturedABSTRACT
Alterations in KRAS have been identified as the most recurring somatic variants in the multiple myeloma (MM) mutational landscape. Combining DNA and RNA sequencing, we studied 756 patients and observed KRAS as the most frequently mutated gene in patients at diagnosis; in addition, we demonstrated the persistence or de novo occurrence of the KRAS aberration at disease relapse. Small-molecule inhibitors targeting KRAS have been developed; however, they are selective for tumors carrying the KRASG12C mutation. Therefore, there is still a need to develop novel therapeutic approaches to target the KRAS mutational events found in other tumor types, including MM. We used AZD4785, a potent and selective antisense oligonucleotide that selectively targets and downregulates all KRAS isoforms, as a tool to dissect the functional sequelae secondary to KRAS silencing in MM within the context of the bone marrow niche and demonstrated its ability to significantly silence KRAS, leading to inhibition of MM tumor growth, both in vitro and in vivo, and confirming KRAS as a driver and therapeutic target in MM.
Subject(s)
Multiple Myeloma/drug therapy , Multiple Myeloma/genetics , Mutation/drug effects , Oligonucleotides, Antisense/pharmacology , Proto-Oncogene Proteins p21(ras)/genetics , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Humans , Mice, SCID , Molecular Targeted Therapy , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/genetics , Oligonucleotides, Antisense/therapeutic use , Small Molecule Libraries/pharmacology , Small Molecule Libraries/therapeutic useABSTRACT
Prostate cancer (PC) is the second most common cancer in men worldwide. Due to the large-scale sequencing efforts, there is currently a better understanding of the genomic landscape of PC. The identification of defects in DNA repair genes has led to clinical studies that provide a strong rationale for developing poly (ADP-ribose) polymerase (PARP) inhibitors and DNA-damaging agents in this molecularly defined subset of patients. The identification of molecularly defined subgroups of patients has also other clinical implications; for example, we now know that carriers of breast cancer 2 (BRCA2) pathogenic sequence variants (PSVs) have increased levels of serum prostate specific antigen (PSA) at diagnosis, increased proportion of high Gleason tumors, elevated rates of nodal and distant metastases, and high recurrence rate; BRCA2 PSVs confer lower overall survival (OS). Distinct tumor PSV, methylation, and expression patterns have been identified in BRCA2 compared with non-BRCA2 mutant prostate tumors. Several DNA damage response and repair (DDR)-targeting agents are currently being evaluated either as single agents or in combination in patients with PC. In this review article, we highlight the biology and clinical implications of deleterious inherited or acquired DNA repair pathway aberrations in PC and offer an overview of new agents being developed for the treatment of PC.
Subject(s)
Neoplasm Recurrence, Local/drug therapy , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms/drug therapy , DNA Damage/genetics , DNA Repair/drug effects , Humans , Male , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Prostatic Neoplasms, Castration-Resistant/genetics , Prostatic Neoplasms, Castration-Resistant/pathologyABSTRACT
Prostate cancer (PC) is the most common cancer in men and the second leading cause of cancer-related death worldwide. Many therapeutic advances over the last two decades have led to an improvement in the survival of patients with metastatic PC, yet the majority of these patients still succumb to their disease. Antiagiogenic therapies have shown substantial benefits for many types of cancer but only a marginal benefit for PC. Ongoing clinical trials investigate antiangiogenic monotherapies or combination therapies. Despite the important role of angiogenesis in PC, clinical trials in refractory castration-resistant PC (CRPC) have demonstrated increased toxicity with no clinical benefit. A better understanding of the mechanism of angiogenesis may help to understand the failure of trials, possibly leading to the development of new targeted anti-angiogenic therapies in PC. These could include the identification of specific subsets of patients who might benefit from these therapeutic strategies. This paper provides a comprehensive review of the pathways involved in the angiogenesis, the chemotherapeutic agents with antiangiogenic activity, the available studies on anti-angiogenic agents and the potential mechanisms of resistance.
Subject(s)
Angiogenesis Inhibitors/therapeutic use , Molecular Targeted Therapy , Neovascularization, Pathologic/drug therapy , Prostatic Neoplasms/blood supply , Prostatic Neoplasms/drug therapy , Angiogenesis Inhibitors/pharmacology , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Drug Resistance, Neoplasm , Humans , MaleABSTRACT
Epithelial ovarian cancer (EOC) accounts for nearly 90% of all ovarian malignancies. The standard therapeutic strategy includes cytoreductive surgery and neo (adjuvant) platinum-based chemotherapy. Relapse of advanced high grade serous ovarian cancer (HGSOC) is related to the development of drug resistance. A defective DNA damage response is a defining hallmark of HGSOC. Poly (ADP-ribose) polymerase (PARP) inhibitors exploit this deficiency through synthetic lethality and have emerged as promising anticancer therapies, especially in breast cancer gene (BRCA1 or BRCA2) mutation carriers. Apart from inducing synthetic lethality, PARP inhibitors have also been shown to trap PARP1 and PARP2 on DNA, leading to PARP-DNA complexes. This "PARP trapping" potentiates synergism between PARP inhibition and both alkylating agents and platinum-based chemotherapy. However, there are remarkable differences in the ability of PARP inhibitors to trap PARP, based on the size and structure of each separate molecule. Since monotherapy with PARP inhibitors is unlikely to induce cancer cell death in BRCA-proficient tumors, the efficacy of PARP inhibitors could be potentially optimized when combined with DNA-damaging agents, or with molecular targeted agents that also impair mechanisms of DNA repair. Olaparib, rucaparib, and niraparib have all obtained US Food and Drug Administration (FDA) and/or European Medicines Agency (EMA) approval in ovarian cancer in different settings. Veliparib does not yet have an approved label; nevertheless, there are currently promising results available in preclinical and early clinical settings. This comprehensive review summarizes the mechanism of action of veliparib and provides an overview of its early and ongoing clinical investigations.
Subject(s)
Benzimidazoles/therapeutic use , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathology , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Female , Humans , PrognosisABSTRACT
Multiple myeloma (MM) is characterized by clonal expansion of malignant plasma cells in the bone marrow (BM). Despite the significant advances in treatment, MM is still a fatal malignancy. This is mainly due to the supportive role of the BM microenvironment in differentiation, migration, proliferation, survival, and drug resistance of the malignant plasma cells. The BM microenvironment is composed of a cellular compartment (stromal cells, osteoblasts, osteoclasts, endothelial cells, and immune cells) and a non-cellular compartment. In this review, we discuss the interaction between the malignant plasma cell and the BM microenvironment and the strategy to target them.
Subject(s)
Bone Marrow/drug effects , Hematopoietic Stem Cell Transplantation , Monoclonal Gammopathy of Undetermined Significance/therapy , Multiple Myeloma/therapy , Plasma Cells/physiology , Tumor Microenvironment/drug effects , Angiogenesis Inhibitors/therapeutic use , Animals , Bone Marrow/immunology , Boronic Acids/therapeutic use , Bortezomib , Humans , Lenalidomide , Multiple Myeloma/mortality , Pyrazines/therapeutic use , Survival Analysis , Thalidomide/analogs & derivatives , Thalidomide/therapeutic use , Treatment OutcomeABSTRACT
Here we show that overexpression or activation of B-cell maturation antigen (BCMA) by its ligand, a proliferation-inducing ligand (APRIL), promotes human multiple myeloma (MM) progression in vivo. BCMA downregulation strongly decreases viability and MM colony formation; conversely, BCMA overexpression augments MM cell growth and survival via induction of protein kinase B (AKT), MAPK, and nuclear factor (NF)-κB signaling cascades. Importantly, BCMA promotes in vivo growth of xenografted MM cells harboring p53 mutation in mice. BCMA-overexpressing tumors exhibit significantly increased CD31/microvessel density and vascular endothelial growth factor compared with paired control tumors. These tumors also express increased transcripts crucial for osteoclast activation, adhesion, and angiogenesis/metastasis, as well as genes mediating immune inhibition including programmed death ligand 1, transforming growth factor ß, and interleukin 10. These target genes are consistently induced by paracrine APRIL binding to BCMA on MM cells, which is blocked by an antagonistic anti-APRIL monoclonal antibody hAPRIL01A (01A). 01A is cytotoxic against MM cells even in the presence of protective bone marrow (BM) myeloid cells including osteoclasts, macrophages, and plasmacytoid dendritic cells. 01A further decreases APRIL-induced adhesion and migration of MM cells via blockade of canonical and noncanonical NF-κB pathways. Moreover, 01A prevents in vivo MM cell growth within implanted human bone chips in SCID mice. Finally, the effect of 01A on MM cell viability is enhanced by lenalidomide and bortezomib. Taken together, these data delineate new molecular mechanisms of in vivo MM growth and immunosuppression critically dependent on BCMA and APRIL in the BM microenvironment, further supporting targeting this prominent pathway in MM.
Subject(s)
B-Cell Maturation Antigen/physiology , Bone Marrow/physiology , Cell Proliferation/genetics , Cellular Microenvironment , Immune Tolerance/genetics , Multiple Myeloma/pathology , Tumor Necrosis Factor Ligand Superfamily Member 13/physiology , Animals , B-Cell Maturation Antigen/genetics , Bone Marrow/pathology , Cell Line, Tumor , Cellular Microenvironment/genetics , Gene Expression Regulation, Neoplastic , Heterografts , Humans , Mice , Mice, SCID , Multiple Myeloma/genetics , Osteoclasts/pathology , Osteoclasts/physiology , Tumor Necrosis Factor Ligand Superfamily Member 13/geneticsABSTRACT
Familial aggregation of Waldenström macroglobulinemia (WM) cases, and the clustering of B-cell lymphoproliferative disorders among first-degree relatives of WM patients, has been reported. Nevertheless, the possible contribution of inherited susceptibility to familial WM remains unrevealed. We performed whole exome sequencing on germ line DNA obtained from 4 family members in which coinheritance for WM was documented in 3 of them, and screened additional independent 246 cases by using gene-specific mutation sequencing. Among the shared germ line variants, LAPTM5(c403t) and HCLS1(g496a) were the most recurrent, being present in 3/3 affected members of the index family, detected in 8% of the unrelated familial cases, and present in 0.5% of the nonfamilial cases and in <0.05 of a control population. LAPTM5 and HCLS1 appeared as relevant WM candidate genes that characterized familial WM individuals and were also functionally relevant to the tumor clone. These findings highlight potentially novel contributors for the genetic predisposition to familial WM and indicate that LAPTM5(c403t) and HCLS1(g496a) may represent predisposition alleles in patients with familial WM.
Subject(s)
Blood Proteins/genetics , Exome , Genetic Predisposition to Disease , Germ-Line Mutation , Membrane Proteins/genetics , Waldenstrom Macroglobulinemia/genetics , Adaptor Proteins, Signal Transducing , Family , Female , High-Throughput Nucleotide Sequencing , Humans , MaleABSTRACT
The tumor suppressors B-lymphocyte-induced maturation protein-1 (BLIMP-1) and p53 play a crucial role in B-cell lymphomas, and their inactivation contributes to the pathogenesis of a wide spectrum of lymphoid malignancies, including diffuse large B-cell lymphomas (DLBCLs). Patients with activated B-cell-like (ABC) DLBCL may present with loss of BLIMP-1, c-Myc over-expression, decreased p53, and poor prognosis. Nevertheless, there is a lack of in vivo models recapitulating the biology of high-grade ABC DLBCL. We therefore aimed to develop an in vivo model aiming to recapitulate the phenotype observed in this cohort of patients. A Cre-Lox approach was used to achieve inactivation of both p53 and BLIMP-1 in murine B-cells. Contextual ablation of BLIMP-1 and p53 led to development of IgM-positive B-cell lymphoma with an aggressive phenotype, supported by c-Myc up-regulation, and accumulation of somatic mutations, as demonstrated by whole exome sequencing. Sensitivity of B-tumor cells to BTK inhibition was demonstrated. This model mirrors what reported in patients with ABC DLBLC, and therefore represents a novel model for studying the biology of ABC-DLBCL harboring the dual loss of BLIMP-1/p53 and c-Myc over-expression.
Subject(s)
B-Lymphocytes/metabolism , B-Lymphocytes/pathology , Cell Transformation, Neoplastic/genetics , Repressor Proteins/deficiency , Tumor Suppressor Protein p53/deficiency , Animals , B-Lymphocytes/drug effects , Biomarkers , Clonal Evolution/genetics , Disease Models, Animal , Gene Expression , Gene Expression Regulation, Neoplastic , Genes, myc , High-Throughput Nucleotide Sequencing , Humans , Mice , Mice, Transgenic , Positive Regulatory Domain I-Binding Factor 1 , Protein Kinase Inhibitors/pharmacologyABSTRACT
PURPOSE OF THE REVIEW: Herein we dissect mechanisms behind the dissemination of cancer cells from primary tumor site to the bone marrow, which are necessary for metastasis development, with a specific focus on multiple myeloma. RECENT FINDINGS: The ability of tumor cells to invade vessels and reach the systemic circulation is a fundamental process for metastasis development; however, the interaction between clonal cells and the surrounding microenvironment is equally important for supporting colonization, survival, and growth in the secondary sites of dissemination. The intrinsic propensity of tumor cells to recognize a favorable milieu where to establish secondary growth is the basis of the "seed and soil" theory. This theory assumes that certain tumor cells (the "seeds") have a specific affinity for the milieu of certain organs (the "soil"). Recent literature has highlighted the important contributions of the vascular niche to the hospitable "soil" within the bone marrow. In this review, we discuss the crucial role of stromal cells and endothelial cells in supporting primary growth, homing, and metastasis to the bone marrow, in the context of multiple myeloma, a plasma cell malignancy with the unique propensity to primarily grow and metastasize to the bone marrow.
Subject(s)
Bone Marrow/blood supply , Bone Neoplasms/secondary , Connective Tissue/blood supply , Endothelial Cells/metabolism , Mesenchymal Stem Cells/metabolism , Multiple Myeloma/pathology , Bone Marrow/metabolism , Connective Tissue/metabolism , Endothelial Cells/cytology , Humans , Mesenchymal Stem Cells/cytology , Multiple Myeloma/metabolism , Neoplasm Metastasis , Tumor MicroenvironmentABSTRACT
Bone is a favorable microenvironment for tumor growth and a frequent destination for metastatic cancer cells. Targeting cancers within the bone marrow remains a crucial oncologic challenge due to issues of drug availability and microenvironment-induced resistance. Herein, we engineered bone-homing polymeric nanoparticles (NPs) for spatiotemporally controlled delivery of therapeutics to bone, which diminish off-target effects and increase local drug concentrations. The NPs consist of poly(D,L-lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG), and bisphosphonate (or alendronate, a targeting ligand). The engineered NPs were formulated by blending varying ratios of the synthesized polymers: PLGA-b-PEG and alendronate-conjugated polymer PLGA-b-PEG-Ald, which ensured long circulation and targeting capabilities, respectively. The bone-binding ability of Ald-PEG-PLGA NPs was investigated by hydroxyapatite binding assays and ex vivo imaging of adherence to bone fragments. In vivo biodistribution of fluorescently labeled NPs showed higher retention, accumulation, and bone homing of targeted Ald-PEG-PLGA NPs, compared with nontargeted PEG-PLGA NPs. A library of bortezomib-loaded NPs (bone-targeted Ald-Bort-NPs and nontargeted Bort-NPs) were developed and screened for optimal physiochemical properties, drug loading, and release profiles. Ald-Bort-NPs were tested for efficacy in mouse models of multiple myeloma (MM). Results demonstrated significantly enhanced survival and decreased tumor burden in mice pretreated with Ald-Bort-NPs versus Ald-Empty-NPs (no drug) or the free drug. We also observed that bortezomib, as a pretreatment regimen, modified the bone microenvironment and enhanced bone strength and volume. Our findings suggest that NP-based anticancer therapies with bone-targeting specificity comprise a clinically relevant method of drug delivery that can inhibit tumor progression in MM.
Subject(s)
Antineoplastic Agents , Bone Neoplasms/drug therapy , Boronic Acids , Drug Delivery Systems , Lactic Acid , Multiple Myeloma/drug therapy , Nanoparticles , Polyethylene Glycols , Polyglycolic Acid , Pyrazines , Tumor Microenvironment/drug effects , Alendronate/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Boronic Acids/chemistry , Boronic Acids/pharmacology , Bortezomib , Cell Line, Tumor , Heterografts , Humans , Lactic Acid/chemical synthesis , Lactic Acid/chemistry , Lactic Acid/pharmacology , Mice , Mice, Inbred BALB C , Mice, Nude , Multiple Myeloma/metabolism , Multiple Myeloma/pathology , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Neoplasm Transplantation , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Polyethylene Glycols/chemical synthesis , Polyethylene Glycols/chemistry , Polyethylene Glycols/pharmacokinetics , Polyglycolic Acid/chemical synthesis , Polyglycolic Acid/chemistry , Polyglycolic Acid/pharmacology , Polylactic Acid-Polyglycolic Acid Copolymer , Pyrazines/chemistry , Pyrazines/pharmacology , Xenograft Model Antitumor AssaysABSTRACT
The CXCR4/stromal cell-derived factor-1 (SDF-1) axis is essential for cell trafficking and has been shown to regulate tumor progression and metastasis in many tumors including multiple myeloma (MM). A second chemokine receptor for SDF-1, CXCR7 was discovered recently and found on activated endothelial cells. We examined the role of CXCR7 in angiogenic mononuclear cells (AMCs) trafficking in MM. Our data demonstrate that AMCs are circulating in patients with MM and in vivo studies show that they specifically home to areas of MM tumor growth. CXCR7 expression is important for regulating trafficking and homing of AMCs into areas of MM tumor growth and neoangiogenesis. We demonstrate that the CXCR7 inhibitor, POL6926, abrogated trafficking of AMCs to areas of MM tumor progression leading to a significant inhibition of tumor progression. These effects were through regulation of endothelial cells and not through a direct tumor effect, indicating that targeting a bone marrow microenvironmental cell can lead to a delay in MM tumor progression. In conclusion, our studies demonstrate that CXCR7 may play an important role in the regulation of tumor progression in MM through an indirect effect on the recruitment of AMCs to areas of MM tumor growth in the bone marrow niche.
Subject(s)
Multiple Myeloma/etiology , Multiple Myeloma/immunology , Receptors, CXCR/metabolism , Animals , Biomimetic Materials/pharmacology , Cell Line, Tumor , Disease Progression , Human Umbilical Vein Endothelial Cells , Humans , Mice , Mice, Inbred BALB C , Mice, SCID , Multiple Myeloma/pathology , Neoplastic Cells, Circulating/immunology , Neoplastic Cells, Circulating/pathology , Neovascularization, Pathologic , Plasma Cells/immunology , Plasma Cells/pathology , Receptors, CXCR/antagonists & inhibitors , Stem Cell Niche/immunology , Tumor Microenvironment/immunologyABSTRACT
The C-X-C chemokine receptor type 4 (CXCR4) plays a crucial role in modulating cell trafficking in hematopoietic stem cells and clonal B cells. We screened 418 patients with B-cell lymphoproliferative disorders and described the presence of the C1013G/CXCR4 warts, hypogammaglobulinemia, infections, and myelokathexis-associated mutation in 28.2% (37/131) of patients with lymphoplasmacytic lymphoma (Waldenström macroglobulinemia [WM]), being either absent or present in only 7% of other B-cell lymphomas. In vivo functional characterization demonstrates its activating role in WM cells, as demonstrated by significant tumor proliferation and dissemination to extramedullary organs, leading to disease progression and decreased survival. The use of a monoclonal antibody anti-CXCR4 led to significant tumor reduction in a C1013G/CXCR4 WM model, whereas drug resistance was observed in mutated WM cells exposed to Bruton's tyrosine kinase, mammalian target of rapamycin, and phosphatidylinositol 3-kinase inhibitors, but not proteasome inhibitors. These findings demonstrate that C1013G/CXCR4 is an activating mutation in WM and support its role as a critical regulator of WM molecular pathogenesis and as an important therapeutic target.
Subject(s)
Drug Resistance, Neoplasm , Enzyme Inhibitors/pharmacology , Mutation, Missense , Receptors, CXCR4/metabolism , Waldenstrom Macroglobulinemia/metabolism , Animals , Cell Proliferation/drug effects , Disease-Free Survival , Female , Heterografts , Humans , Male , Mice , Mice, SCID , Neoplasm Metastasis , Neoplasm Transplantation , Receptors, CXCR4/genetics , Survival Rate , Waldenstrom Macroglobulinemia/drug therapy , Waldenstrom Macroglobulinemia/genetics , Waldenstrom Macroglobulinemia/mortality , Waldenstrom Macroglobulinemia/pathologyABSTRACT
Proline-rich tyrosine kinase 2 (Pyk2) is a member of the focal adhesion kinase family that has been recently linked to tumor development. However, its role in modulating multiple myeloma (MM) biology and disease progression remains unexplored. We first demonstrated that patients with MM present with higher expression of Pyk2 compared with healthy individuals. By using loss-of-function approaches, we found that Pyk2 inhibition led to reduction of MM tumor growth in vivo as well as decreased cell proliferation, cell-cycle progression, and adhesion ability in vitro. In turn, overexpression of Pyk2 promoted the malignant phenotype, substantiated by enhanced tumor growth and reduced survival. Mechanistically, inhibition of Pyk2 reduced activation of Wnt/ß-catenin signaling by destabilizing ß-catenin, leading to downregulation of c-Myc and Cyclin D1. Furthermore, treatment of MM cells with the FAK/Pyk2 inhibitor VS-4718 effectively inhibited MM cell growth both in vitro and in vivo. Collectively, our findings describe the tumor-promoting role of Pyk2 in MM, thus providing molecular evidence for a novel tyrosine kinase inhibitor as a new therapeutic option in MM.
Subject(s)
Aminopyridines/pharmacology , Focal Adhesion Kinase 2/antagonists & inhibitors , Multiple Myeloma/prevention & control , Protein Kinase Inhibitors/pharmacology , Xenograft Model Antitumor Assays , Animals , Cell Adhesion/drug effects , Cell Adhesion/genetics , Cell Cycle/drug effects , Cell Cycle/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Cells, Cultured , Disease Progression , Female , Focal Adhesion Kinase 2/genetics , Focal Adhesion Kinase 2/metabolism , Gene Expression Regulation, Enzymologic/drug effects , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , HEK293 Cells , Humans , Immunoblotting , Luminescent Measurements , Mice, SCID , Multiple Myeloma/genetics , Multiple Myeloma/metabolism , RNA Interference , Reverse Transcriptase Polymerase Chain Reaction , Survival Analysis , Tumor Burden/drug effects , Tumor Burden/genetics , Wnt Signaling Pathway/drug effects , beta Catenin/metabolismABSTRACT
Glycosylation is a stepwise procedure of covalent attachment of oligosaccharide chains to proteins or lipids, and alterations in this process, especially increased sialylation, have been associated with malignant transformation and metastasis. The role of altered sialylation in multiple myeloma (MM) cell trafficking has not been previously investigated. In the present study we identified high expression of ß-galactoside α-2,3-sialyltransferase, ST3GAL6, in MM cell lines and patients. This gene plays a key role in selectin ligand synthesis in humans through the generation of functional sialyl Lewis X. In MRC IX patients, high expression of this gene is associated with inferior overall survival. In this study we demonstrate that knockdown of ST3GAL6 results in a significant reduction in levels of α-2,3-linked sialic acid on the surface of MM cells with an associated significant reduction in adhesion to MM bone marrow stromal cells and fibronectin along with reduced transendothelial migration in vitro. In support of our in vitro findings, we demonstrate significantly reduced homing and engraftment of ST3GAL6 knockdown MM cells to the bone marrow niche in vivo, along with decreased tumor burden and prolonged survival. This study points to the importance of altered glycosylation, particularly sialylation, in MM cell adhesion and migration.
Subject(s)
Multiple Myeloma/enzymology , Neoplasm Proteins/metabolism , Sialyltransferases/metabolism , Transendothelial and Transepithelial Migration , Animals , Bone Marrow Cells/enzymology , Bone Marrow Cells/pathology , Cell Adhesion/genetics , Cell Line, Tumor , Cell Survival/genetics , Female , Gene Knockdown Techniques , Human Umbilical Vein Endothelial Cells , Humans , Male , Mice , Mice, SCID , Multiple Myeloma/genetics , Multiple Myeloma/pathology , N-Acetylneuraminic Acid/biosynthesis , N-Acetylneuraminic Acid/genetics , Neoplasm Proteins/genetics , Sialyltransferases/genetics , Stromal Cells/enzymology , Stromal Cells/pathology , beta-Galactoside alpha-2,3-SialyltransferaseABSTRACT
Unprecedented advances in multiple myeloma (MM) therapy during the last 15 years are predominantly based on our increasing understanding of the pathophysiologic role of the bone marrow (BM) microenvironment. Indeed, new treatment paradigms, which incorporate thalidomide, immunomodulatory drugs (IMiDs), and proteasome inhibitors, target the tumor cell as well as its BM microenvironment. Ongoing translational research aims to understand in more detail how disordered BM-niche functions contribute to MM pathogenesis and to identify additional derived targeting agents. One of the most exciting advances in the field of MM treatment is the emergence of immune therapies including elotuzumab, daratumumab, the immune checkpoint inhibitors, Bispecific T-cell engagers (BiTes), and Chimeric antigen receptor (CAR)-T cells. This chapter will review our knowledge on the pathophysiology of the BM microenvironment and discuss derived novel agents that hold promise to further improve outcome in MM.
Subject(s)
Multiple Myeloma/pathology , Multiple Myeloma/physiopathology , Tumor Microenvironment , Animals , Bone Marrow/pathology , Bone Marrow/physiopathology , HumansABSTRACT
Tumor-associated neovasculature is a critical therapeutic target; however, despite significant progress made in the clinical efficacy of anti-vessel drugs, the effect of these agents remains transient: over time, most patients develop resistance, which inevitably leads to tumor progression. To develop more effective treatments, it is imperative that we better understand the mechanisms involved in tumor vessel formation, how they participate to the tumor progression and metastasis, and the best way to target them. Several mechanisms contribute to the formation of tumor-associated vasculature: i) neoangiogenesis; ii) vascular co-option; iii) mosaicism; iv) vasculogenic mimicry, and v) postnatal vasculogenesis. These mechanisms can also play a role in the development of resistance to anti-angiogenic drugs, and could serve as targets for designing new anti-vascular molecules to treat solid as well as hematological malignancies. Bone marrow-derived endothelial progenitor cell (EPC)-mediated vasculogenesis represents an important new target, especially at the early stage of tumor growth (when EPCs are critical for promoting the "angiogenic switch"), and during metastasis, when EPCs promote the transition from micro- to macro-metastases. In hematologic malignancies, the EPC population could be related to the neoplastic clone, and both may share a common ontogeny. Thus, characterization of tumor-associated EPCs in blood cancers may provide clues for more specific anti-vascular therapy that has both direct and indirect anti-tumor effects. Here, we review the role of vasculogenesis, mediated by bone marrow-derived EPCs, in the progression of cancer, with a particular focus on the role of these cells in promoting progression of hematological malignancies.
Subject(s)
Endothelial Cells/pathology , Neoplasms/blood supply , Neoplasms/pathology , Neovascularization, Pathologic/pathology , Stem Cells/pathology , Animals , Disease Progression , Hematologic Neoplasms/pathology , HumansABSTRACT
The phosphatidylinositol-3 kinase (PI3K) pathway is activated in multiple myeloma (MM) and Waldenstrom Macroglobulenima (WM), and plays a crucial role in tumor progression and drug resistance. In this study, we characterized the role of pan-class I PI3K inhibition on cell trafficking and survival of MM and WM cells. We tested the effect of pan-class I PI3K inhibition by siRNA silencing or pharmacologic inhibition with buparlisib on MM cell survival, apoptosis and cell cycle in vitro and tumor growth and mobilization of MM cells in vivo. We then evaluated buparlisib-dependent mechanisms of induced MM cell mobilization. Moreover, the effect of buparlisib on cell survival, apoptosis, and adhesion of WM cells to bone marrow stromal cells (BMSCs) has been evaluated. We showed that buparlisib induced toxicity in MM cells, supported by induction of apoptosis and cell cycle arrest. Buparlisib was also found to reduce tumor progression in vivo. Importantly, buparlisib enhanced MM cell mobilization in vivo which was driven by decreased adhesion of MM cells to BMSCs and increased chemotaxis via up-regulation of CXCR4 expression. Similar to its effects on MM cells, buparlisib also induced cell survival and apoptosis, and decreased adhesion in WM cells. These data highlight the critical contribution of class I PI3K signaling to the regulation of survival and cell dissemination in B-cell malignancies.
Subject(s)
Aminopyridines/pharmacology , Antineoplastic Agents/pharmacology , Morpholines/pharmacology , Multiple Myeloma/pathology , Neoplasm Proteins/antagonists & inhibitors , Phosphoinositide-3 Kinase Inhibitors , Protein Kinase Inhibitors/pharmacology , Waldenstrom Macroglobulinemia/pathology , Aminopyridines/therapeutic use , Animals , Apoptosis/drug effects , Cell Adhesion/drug effects , Cell Cycle/drug effects , Cell Line , Cell Line, Tumor , Chemotaxis/drug effects , Coculture Techniques , Drug Screening Assays, Antitumor , Female , Fibronectins , Humans , Mesenchymal Stem Cells/cytology , Mice , Mice, SCID , Morpholines/therapeutic use , Multiple Myeloma/enzymology , Neoplasm Invasiveness , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , RNA Interference , RNA, Small Interfering/pharmacology , Receptors, CXCR4/biosynthesis , Receptors, CXCR4/genetics , Waldenstrom Macroglobulinemia/enzymology , Xenograft Model Antitumor AssaysABSTRACT
Pentraxin 3 (PTX3) is a soluble pattern recognition receptor that binds with high affinity and selectivity to fibroblast growth factor-2 (FGF2), thus inhibiting its pro-angiogenic activity. Here we investigated the effects of PTX3 on monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) patient-derived bone marrow (BM) plasma cells (PCs), endothelial cells (ECs), and fibroblasts (FBs), and assessed whether PTX3 can modulate the cross-talk between PCs and those microenvironment cells. PTX3 and FGF2 expression was evaluated by ELISA. Functional studies, including cell viability, wound healing, chemotaxis, and Matrigel(®) assays, were performed on MGUS and MM ECs and FBs upon the PTX3 treatment. Through western blot PTX3-induced modulation in FGF2/FGF receptor signalling pathways was evaluated in MGUS and MM ECs and FBs through western blot. Co-cultures between MM ECs/FBs and human PC lines were used to evaluate possible PTX3 indirect effects on MM PCs. Adhesion molecules were studied by flow cytometry. PTX3 provides a direct time- and dose-dependent apoptotic effect on MM ECs and FBs, but not on either MM primary PCs or human PC lines. PTX3 inhibits migration of MM ECs and FBs in a dose-dependent manner, and impacts in vitro and in vivo FGF2-mediated MM angiogenesis. Co-cultures of PCs and ECs/FBs show that PTX3 treatment indirectly impairs PC viability and adhesion. We conclude that PTX3 is an anti-angiogenic factor in MM and behaves as a cytotoxic molecule on MM cells by inhibiting the cross-talk between PCs and ECs/FBs.
Subject(s)
Bone Marrow Cells/metabolism , C-Reactive Protein/metabolism , Cell Communication , Endothelial Cells/metabolism , Fibroblasts/metabolism , Multiple Myeloma/metabolism , Plasma Cells/metabolism , Serum Amyloid P-Component/metabolism , Adult , Aged , Aged, 80 and over , Animals , Apoptosis , Blotting, Western , Bone Marrow Cells/pathology , Case-Control Studies , Cell Adhesion , Cell Adhesion Molecules/metabolism , Cell Line , Cellular Microenvironment , Chemotaxis , Chick Embryo , Coculture Techniques , Culture Media, Conditioned/metabolism , Cytokines/metabolism , Endothelial Cells/pathology , Enzyme-Linked Immunosorbent Assay , Female , Fibroblast Growth Factor 2/metabolism , Fibroblasts/pathology , Flow Cytometry , Humans , Male , Middle Aged , Monoclonal Gammopathy of Undetermined Significance/metabolism , Monoclonal Gammopathy of Undetermined Significance/pathology , Multiple Myeloma/blood supply , Multiple Myeloma/pathology , Neovascularization, Pathologic , Plasma Cells/pathology , Receptors, Fibroblast Growth Factor/metabolism , Signal Transduction , Time Factors , Tumor Cells, CulturedABSTRACT
Head and neck squamous cell carcinoma (HNSCC) is a deadly disease with a poor prognosis due to late diagnosis and limited treatment options. Immunotherapy (IT) is emerging as a promising approach, especially after the failure of standard of care therapies (STs). The objective of this systematic review and meta-analysis was to evaluate whether the addition of IT to STs improves outcomes for patients with HNSCC, including overall survival (OS), progression-free survival (PFS), and quality of life (QoL). This review employed the Population Intervention Comparison and Outcome (PICO) framework to identify relevant search terms in electronic databases, and also included supplementary hand searches. Six primary research articles were selected using the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) flow chart, and were critically appraised. Data extraction from these studies was conducted, and a meta-analysis was performed to aid in the generation of forest plots. The addition of IT to standard anticancer therapies was found to enhance patient outcomes, such as OS, PFS, and QoL. The toxicity profile of IT was acceptable, with minimal treatment-related deaths. The most frequently observed adverse events (AE) were related to the skin, followed by hematological toxicities. Based on our analysis, the addition of IT to STs is a suitable treatment option and is supported by current research. However, further studies are needed to investigate factors that influence treatment effectiveness and to develop optimal therapies. To achieve this, we recommend a comprehensive treatment approach that involves the multidisciplinary team (MDT) and patient assessment tools.