Search results for "therapy resistance"
showing 10 items of 12 documents
Functional characterization of circulating tumor cells (CTCs) from metastatic ER+/HER2− breast cancer reveals dependence on HER2 and FOXM1 for endocr…
2021
Simple Summary Acquired endocrine resistance and late recurrence in patients with ER+/HER2− breast cancer are complex and not fully understood. Here, we evaluated mechanisms of acquired resistance in circulating tumor cells (CTCs) from an ER+/HER2− breast cancer patient who initially responded but later progressed under endocrine treatment. We found a switch from ERα-dependent to HER2-dependent and ERα-independent expression of FOXM1, which may enable disseminated ER+/HER2− cells to re-initiate tumor cell growth and metastasis formation in the presence of endocrine treatment. We found that NFkB signaling sustains HER2 and FOXM1 expression in CTCs in the presence of ERα inhibitors suggesting…
Effects of mutations in Wnt/β-catenin, hedgehog, Notch and PI3K pathways on GSK-3 activity—Diverse effects on cell growth, metabolism and cancer
2016
Glycogen synthase kinase-3 (GSK-3) is a serine/threonine kinase that participates in an array of critical cellular processes. GSK-3 was first characterized as an enzyme that phosphorylated and inactivated glycogen synthase. However, subsequent studies have revealed that this moon-lighting protein is involved in numerous signaling pathways that regulate not only metabolism but also have roles in: apoptosis, cell cycle progression, cell renewal, differentiation, embryogenesis, migration, regulation of gene transcription, stem cell biology and survival. In this review, we will discuss the roles that GSK-3 plays in various diseases as well as how this pivotal kinase interacts with multiple sign…
Anti-angiogenic agents in the age of resistance to immune checkpoint inhibitors: Do they have a role in non-oncogene-addicted non-small cell lung can…
2020
The introduction of licensed front-line immunotherapies has heralded a new era for the treatment of non-oncogene-addicted, advanced non-small cell lung cancer (NSCLC). Yet as with all evolutions in clinical management, changes in practice can outpace the availability of the clinical evidence needed to inform subsequent therapeutic decision making. At the time of writing, there is limited available evidence on the optimum therapeutic options after progression on immunotherapy. Further research is needed to define mechanisms of immunotherapy resistance in patients with advanced NSCLC, and to understand the implications for subsequent treatment response. Pending the availability of robust clin…
Multifaceted roles of GSK-3 and Wnt/beta-catenin in hematopoiesis and leukemogenesis: opportunities for therapeutic intervention
2013
Glycogen synthase kinase-3 (GSK-3) is well documented to participate in a complex array of critical cellular processes. It was initially identified in rat skeletal muscle as a serine/threonine kinase that phosphorylated and inactivated glycogen synthase. This versatile protein is involved in numerous signaling pathways that influence metabolism, embryogenesis, differentiation, migration, cell cycle progression and survival. Recently, GSK-3 has been implicated in leukemia stem cell pathophysiology and may be an appropriate target for its eradication. In this review, we will discuss the roles that GSK-3 plays in hematopoiesis and leukemogenesis as how this pivotal kinase can interact with mul…
Mutations and Deregulation of Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR Cascades Which Alter Therapy Response.
2012
The Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR cascades are often activated by genetic alterations in upstream signaling molecules such as receptor tyrosine kinases (RTK). Certain components of these pathways, RAS, NF1, BRAF, MEK1, DUSP5, PP2A, PIK3CA, PIK3R1, PIK3R4, PIK3R5, IRS4, AKT, NFKB1, MTOR, PTEN, TSC1, and TSC2 may also be activated/inactivated by mutations or epigenetic silencing. Upstream mutations in one signaling pathway or even in downstream components of the same pathway can alter the sensitivity of the cells to certain small molecule inhibitors. These pathways have profound effects on proliferative, apoptotic and differentiation pathways. Dysregulation of components of these cas…
Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR cascade inhibitors: How mutations can result in therapy resistance and how to overcome resistance
2012
// James A. McCubrey 1 , Linda S. Steelman 1 , William H. Chappell 1 , Stephen L. Abrams 1 , Richard A. Franklin 1 , Giuseppe Montalto 2 , Melchiorre Cervello 3 , Massimo Libra 4 , Saverio Candido 4 , Grazia Malaponte 4 , Maria C. Mazzarino 4 , Paolo Fagone 4 , Ferdinando Nicoletti 4 , Jorg Basecke 5 , Sanja Mijatovic 6 , Danijela Maksimovic-Ivanic 6 , Michele Milella 7 , Agostino Tafuri 8 , Francesca Chiarini 9 , Camilla Evangelisti 9 , Lucio Cocco 10 , Alberto M. Martelli 9,10 1 Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, USA 2 Department of Internal Medicine and Specialties, University of Palermo, Palermo, Italy 3 Consi…
Roles of signaling pathways in drug resistance, cancer initiating cells and cancer progression and metastasis
2014
The EGFR/PI3K/PTEN/Akt/mTORC pathway plays prominent roles in malignant transformation, prevention of apoptosis, drug resistance, cancer initiating cells (CICs) and metastasis. The expression of this pathway is frequently altered in breast and other cancers due to mutations at or aberrant expression of: HER2, EGFR1, PIK3CA, and PTEN as well as other oncogenes and tumor suppressor genes. miRs and epigenetic mechanisms of gene regulation are also important events which regulate this pathway. In some breast cancer cases, mutations at certain components of this pathway (e.g., PIK3CA) are associated with a better prognosis than breast cancers lacking these mutations. The expression of this pathw…
Targeting breast cancer initiating cells: advances in breast cancer research and therapy
2014
Over the past 10 years there have been significant advances in our understanding of breast cancer and the important roles that breast cancer initiating cells (CICs) play in the development and resistance of breast cancer. Breast CICs endowed with self-renewing and tumor-initiating capacities are believed to be responsible for the relapses which often occur after various breast cancer therapies. In this review, we will summarize some of the key developments in breast CICs which will include discussion of some of the key genes implicated: estrogen receptor (. ER), HER2, BRCA1, TP53, PIK3CA, RB, P16INK1 and various miRs as well some drugs which are showing promise in targeting CICs. In additio…
Deregulation of the EGFR/PI3K/PTEN/Akt/mTORC1 pathway in breast cancer: possibilities for therapeutic intervention
2014
// Nicole M. Davis 1 , Melissa Sokolosky 1 , Kristin Stadelman 1 , Stephen L. Abrams 1 , Massimo Libra 2 , Saverio Candido 2 , Ferdinando Nicoletti 2 , Jerry Polesel 3 , Roberta Maestro 4 , Antonino D’Assoro 5 , Lyudmyla Drobot 6 , Dariusz Rakus 7 , Agnieszka Gizak 7 , Piotr Laidler 8 , Joanna Dulinska-Litewka 8 , Joerg Basecke 9 , Sanja Mijatovic 10 , Danijela Maksimovic-Ivanic 10 , Giuseppe Montalto 11,12 , Melchiorre Cervello 12 , Timothy L. Fitzgerald 13 , Zoya N. Demidenko 14 , Alberto M. Martelli 15 , Lucio Cocco 15 , Linda S. Steelman 1 and James A. McCubrey 1 1 Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University Greenville, NC 27858 USA 2 …
Effective targeting of breast cancer stem cells by combined inhibition of Sam68 and Rad51
2022
AbstractBreast cancer (BC) is the second cause of cancer-related deceases in the worldwide female population. Despite the successful treatment advances, 25% of BC develops resistance to current therapeutic regimens, thereby remaining a major hurdle for patient management. Current therapies, targeting the molecular events underpinning the adaptive resistance, still require effort to improve BC treatment. Using BC sphere cells (BCSphCs) as a model, here we showed that BC stem-like cells express high levels of Myc, which requires the presence of the multifunctional DNA/RNA binding protein Sam68 for the DNA-damage repair. Analysis of a cohort of BC patients displayed that Sam68 is an independen…