scholarly journals Emerging treatment options for patients with p53-pathway-deficient CLL

2019 ◽  
Vol 10 ◽  
pp. 204062071989135 ◽  
Author(s):  
Marisa J. L. Aitken ◽  
Hun J. Lee ◽  
Sean M. Post
Keyword(s):  
Cell Cycle ◽  
Chronic Lymphocytic Leukemia ◽  
Tumor Suppressors ◽  
Cancer Biology ◽  
Treatment Options ◽  
Neoplastic Transformation ◽  
Lymphocytic Leukemia ◽  
P53 Pathway ◽  
The Past ◽  
Cycle Arrest

Over the past 40 years, p53 has been the most widely studied protein in cancer biology. Originally thought to be an oncogene due to its stabilization in many cancers, it is now considered to be one of the most critical tumor suppressors in a cell’s ability to combat neoplastic transformation. Due to its critical roles in apoptosis, cell-cycle arrest, and senescence, TP53 deletions and mutations are commonly observed and are often a portent of treatment failures and poor clinical outcomes. This is particularly true in chronic lymphocytic leukemia (CLL), as patients with p53 alterations have historically had dismal outcomes. As such, the tremendous efforts made to better understand the functions of p53 in CLL have contributed substantially to recent advances in treating patients with p53-pathway-deficient CLL.

scholarly journals T Cell Defects and Immunotherapy in Chronic Lymphocytic Leukemia

Cancers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 3255
Author(s):  
Elisavet Vlachonikola ◽  
Kostas Stamatopoulos ◽  
Anastasia Chatzidimitriou
Keyword(s):  
T Cell ◽  
Chronic Lymphocytic Leukemia ◽  
Immune Responses ◽  
B Lymphocytes ◽  
Therapeutic Option ◽  
Treatment Options ◽  
Lymphocytic Leukemia ◽  
Cell Compartment ◽  
The Past ◽  
Great Dependency

In the past few years, independent studies have highlighted the relevance of the tumor microenvironment (TME) in cancer, revealing a great variety of TME-related predictive markers, as well as identifying novel therapeutic targets in the TME. Cancer immunotherapy targets different components of the immune system and the TME at large in order to reinforce effector mechanisms or relieve inhibitory and suppressive signaling. Currently, it constitutes a clinically validated treatment for many cancers, including chronic lymphocytic leukemia (CLL), an incurable malignancy of mature B lymphocytes with great dependency on microenvironmental signals. Although immunotherapy represents a promising therapeutic option with encouraging results in CLL, the dysfunctional T cell compartment remains a major obstacle in such approaches. In the scope of this review, we outline the current immunotherapeutic treatment options in CLL in the light of recent immunogenetic and functional evidence of T cell impairment. We also highlight possible approaches for overcoming T cell defects and invigorating potent anti-tumor immune responses that would enhance the efficacy of immunotherapy.

scholarly journals Selective Inhibition of Aurora Kinase A by AK-01/LY3295668 Attenuates MCC Tumor Growth by Inducing MCC Cell Cycle Arrest and Apoptosis

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3708
Author(s):  
Bhaba K. Das ◽  
Aarthi Kannan ◽  
Quy Nguyen ◽  
Jyoti Gogoi ◽  
Haibo Zhao ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Checkpoint Inhibitors ◽  
Treatment Options ◽  
Standard Of Care ◽  
Aurora Kinase ◽  
Selective Inhibition ◽  
Potential Candidate ◽  
Cycle Arrest

Merkel cell carcinoma (MCC) is an often-lethal skin cancer with increasing incidence and limited treatment options. Although immune checkpoint inhibitors (ICI) have become the standard of care in advanced MCC, 50% of all MCC patients are ineligible for ICIs, and amongst those treated, many patients develop resistance. There is no therapeutic alternative for these patients, highlighting the urgent clinical need for alternative therapeutic strategies. Using patient-derived genetic insights and data generated in our lab, we identified aurora kinase as a promising therapeutic target for MCC. In this study, we examined the efficacy of the recently developed and highly selective AURKA inhibitor, AK-01 (LY3295668), in six patient-derived MCC cell lines and two MCC cell-line-derived xenograft mouse models. We found that AK-01 potently suppresses MCC survival through apoptosis and cell cycle arrest, particularly in MCPyV-negative MCC cells without RB expression. Despite the challenge posed by its short in vivo durability upon discontinuation, the swift and substantial tumor suppression with low toxicity makes AK-01 a strong potential candidate for MCC management, particularly in combination with existing regimens.

scholarly journals Tumor Suppressor Inactivation in the Pathogenesis of Adult T-Cell Leukemia

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Christophe Nicot
Keyword(s):  
Cell Cycle ◽  
T Cell ◽  
Tumor Suppressor ◽  
Cell Cycle Arrest ◽  
Tumor Suppressors ◽  
Epigenetic Mechanisms ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Adult T Cell Leukemia ◽  
Cycle Arrest

Tumor suppressor functions are essential to control cellular proliferation, to activate the apoptosis or senescence pathway to eliminate unwanted cells, to link DNA damage signals to cell cycle arrest checkpoints, to activate appropriate DNA repair pathways, and to prevent the loss of adhesion to inhibit initiation of metastases. Therefore, tumor suppressor genes are indispensable to maintaining genetic and genomic integrity. Consequently, inactivation of tumor suppressors by somatic mutations or epigenetic mechanisms is frequently associated with tumor initiation and development. In contrast, reactivation of tumor suppressor functions can effectively reverse the transformed phenotype and lead to cell cycle arrest or death of cancerous cells and be used as a therapeutic strategy. Adult T-cell leukemia/lymphoma (ATLL) is an aggressive lymphoproliferative disease associated with infection of CD4 T cells by the Human T-cell Leukemia Virus Type 1 (HTLV-I). HTLV-I-associated T-cell transformation is the result of a multistep oncogenic process in which the virus initially induces chronic T-cell proliferation and alters cellular pathways resulting in the accumulation of genetic defects and the deregulated growth of virally infected cells. This review will focus on the current knowledge of the genetic and epigenetic mechanisms regulating the inactivation of tumor suppressors in the pathogenesis of HTLV-I.

scholarly journals Drosophila neuroblast asymmetric divisions: cell cycle regulators, asymmetric protein localization, and tumorigenesis

2008 ◽  
Vol 180 (2) ◽  
pp. 267-272 ◽  
Author(s):  
William Chia ◽  
W. Gregory Somers ◽  
Hongyan Wang
Keyword(s):  
Cell Cycle ◽  
Tumor Suppressors ◽  
System Development ◽  
Protein Localization ◽  
Asymmetric Division ◽  
Nervous System Development ◽  
Cell Cycle Regulators ◽  
The Past ◽  
Larval Nervous System ◽  
Asymmetric Divisions

Over the past decade, many of the key components of the genetic machinery that regulate the asymmetric division of Drosophila melanogaster neural progenitors, neuroblasts, have been identified and their functions elucidated. Studies over the past two years have shown that many of these identified components act to regulate the self-renewal versus differentiation decision and appear to function as tumor suppressors during larval nervous system development. In this paper, we highlight the growing number of molecules that are normally considered to be key regulators of cell cycle events/progression that have recently been shown to impinge on the neuroblast asymmetric division machinery to control asymmetric protein localization and/or the decision to self-renew or differentiate.

scholarly journals Expression of the c-myc proto-oncogene in multiple myeloma and chronic lymphocytic leukemia: an in situ analysis

Blood ◽  
1991 ◽  
Vol 78 (1) ◽  
pp. 180-191 ◽  
Author(s):  
R Greil ◽  
B Fasching ◽  
P Loidl ◽  
H Huber
Keyword(s):  
Cell Cycle ◽  
Multiple Myeloma ◽  
Chronic Lymphocytic Leukemia ◽  
Peripheral Blood ◽  
Proliferative Activity ◽  
Plasma Cells ◽  
Lymphocytic Leukemia ◽  
Myc Gene ◽  
Gene Transcripts

Abstract The c-myc gene plays a pivotal role in mediating the competence state for cell cycle transversion. This biologic role is in contradiction to reports of elevated expression of the gene in multiple myeloma, a tumor with restricted self-renewal capacity. To more clearly define the role of this gene in plasma cells of myeloma patients, c-myc messenger RNA (mRNA) and/or oncoprotein expression were semiquantitatively analyzed on the single cell level in 19 cases of multiple myeloma, among them 1 biclonal case and 1 case with coexistent chronic lymphocytic leukemia (CLL). Performing anti-sense/mRNA in situ hybridization, mature c-myc gene transcripts were detected in 92% (12 of 13) of cases and could definitely be attributed to the plasma cells by our study. The number of Ki 67-positive plasma cells actively passing the cell cycle was less than 1% and independent of c-myc gene expression. However, because the presence of the 152-c-MYC epitope was correlated to extent of marrow plasmacytosis (r = .64; P = .043) and content of plasmablasts (P = .09), the c-myc gene might serve a function different from proliferative activity, but also associated with tumor cell mass. In CLL cells (21 of 22 cases) and their benign counterparts, ie, bone marrow and peripheral blood lymphocytes, the anti-sense/c-myc mRNA hybridization signals remained below the threshold considered as cutpoint between negative and positive. The low amounts of c-myc transcripts were correlated to neither stage of disease (P = .52) nor lymphocyte counts (P = .24). Because the numbers of peripheral blood lymphoma cells were independent of tumor mass and of c-myc gene transcripts expressed, peripheral blood lymphocytosis might more likely reflect homing processes than proliferative activity in CLL.

BCR ligation induced by IgM stimulation results in gene expression and functional changes only in IgVH unmutated chronic lymphocytic leukemia (CLL) cells

Blood ◽  
2008 ◽  
Vol 112 (3) ◽  
pp. 782-792 ◽  
Author(s):  
Anna Guarini ◽  
Sabina Chiaretti ◽  
Simona Tavolaro ◽  
Roberta Maggio ◽  
Nadia Peragine ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Chronic Lymphocytic Leukemia ◽  
Lymphocytic Leukemia ◽  
Cross Linking ◽  
Cell Cycle Distribution ◽  
Moderate Increase ◽  
Functional Changes ◽  
Cytoskeleton Organization ◽  
Different Response

Abstract Chronic lymphocytic leukemia (CLL) patients exhibit a variable clinical course. To investigate the association between clinicobiologic features and responsiveness of CLL cells to anti-IgM stimulation, we evaluated gene expression changes and modifications in cell-cycle distribution, proliferation, and apoptosis of IgVH mutated (M) and unmutated (UM) samples upon BCR cross-linking. Unsupervised analysis highlighted a different response profile to BCR stimulation between UM and M samples. Supervised analysis identified several genes modulated exclusively in the UM cases upon BCR cross-linking. Functional gene groups, including signal transduction, transcription, cell-cycle regulation, and cytoskeleton organization, were up-regulated upon stimulation in UM cases. Cell-cycle and proliferation analyses confirmed that IgM cross-linking induced a significant progression into the G1 phase and a moderate increase of proliferative activity exclusively in UM patients. Moreover, we observed only a small reduction in the percentage of subG0/1 cells, without changes in apoptosis, in UM cases; contrariwise, a significant increase of apoptotic levels was observed in stimulated cells from M cases. These results document that a differential genotypic and functional response to BCR ligation between IgVH M and UM cases is operational in CLL, indicating that response to antigenic stimulation plays a pivotal role in disease progression.

How I treat chronic lymphocytic leukemia after venetoclax

Blood ◽  
2021 ◽  
Author(s):  
Thomas E Lew ◽  
Constantine S. Tam ◽  
John F. Seymour
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Residual Disease ◽  
Treatment Options ◽  
Cell Receptor ◽  
Resistance Mechanisms ◽  
Lymphocytic Leukemia ◽  
Bcl2 Family ◽  
Clinical Scenarios ◽  
Car T

Venetoclax-based regimens have expanded the therapeutic options for patients with chronic lymphocytic leukemia (CLL), frequently achieving remissions with undetectable measurable residual disease (uMRD) and facilitating time-limited treatment without utilizing chemotherapy. Although response rates are high and durable disease control is common, longer-term follow-up of patients with relapsed and refractory (RR) disease, especially in the presence of TP53 aberrations, demonstrates frequent disease resistance and progression. Although the understanding of venetoclax resistance remains incomplete, progressive disease (PD) is typified by oligoclonal leukemic populations with distinct resistance mechanisms, including BCL2 mutations, upregulation of alternative BCL2 family proteins and genomic instability. Although most commonly observed in heavily pre-treated patients with disease refractory to fludarabine and harboring complex karyotype (CK), Richter transformation (RT) presents a distinct and challenging manifestation of venetoclax resistance. For patients with progressive CLL after venetoclax, treatment options include B-cell receptor pathway inhibitors (BCRis), allogeneic stem cell transplantation (SCT), chimeric antigen receptor (CAR) T-cells, and venetoclax re-treatment for those with disease relapsing after time-limited therapy. However, data to inform clinical decisions for these patients are limited. We review the biology of venetoclax resistance and outline an approach to the common clinical scenarios encountered after venetoclax-based therapy that will increasingly confront practising clinicians.

Sign in / Sign up

Export Citation Format

Share Document