Resistance to Chemotherapy

The issue of resistance to targeted drug therapy is of pressing concern, as it constitutes a major barrier to progress in managing cancer. One important aspect is the role of stochasticity in determining the nature of the patient response. We examine two particular experiments. The first measured the maximal response of melanoma to targeted therapy before the resistance causes the tumor to progress. We analyze the data in the context of a Delbruck–Luria type scheme, wherein the continued growth of preexistent resistant cells are responsible for progression. We show that, aside from a finite fraction of resistant cell-free patients, the maximal response in such a scenario would be quite uniform. To achieve the measured variability, one is necessarily led to assume a wide variation from patient to patient of the sensitive cells' response to the therapy. The second experiment is an in vitro system of multiple myeloma cells. When subject to a spatial gradient of a chemotherapeutic agent, the cells in the middle of the system acquire resistance on a rapid (two-week) timescale. This finding points to the potential important role of cell-to-cell differences, due to differing local environments, in addition to the patient-to-patient differences encountered in the first part. See all articles in this Cancer Research section, “Physics in Cancer Research.” Cancer Res; 74(17); 4663–70. ©2014 AACR.
Source: Cancer Research - Category: Cancer & Oncology Authors: Tags: Physics in Cancer Research Source Type: research

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Discussion MDSCs violently emerge in pathological conditions in an attempt to limit potentially harmful immune and inflammatory responses. Mechanisms supporting their expansion and survival are deeply investigated in cancer, in the perspective to reactivate specific antitumor responses and prevent their contribution to disease evolution. These findings will likely contribute to improve the targeting of MDSCs in anticancer immunotherapies, either alone or in combination with immune checkpoint inhibitors. New evidence indicates that the expansion of myeloid cell differentiation in pathology is subject to fine-tuning, as its...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
Antonio Lucena-Cacace1, Masayuki Umeda1, Lola E. Navas2,3 and Amancio Carnero2,3* 1Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application, Kyoto University, Kyoto, Japan 2CIBERONC, ISCIII, Madrid, Spain 3Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío (HUVR), CSIC, Universidad de Sevilla, Sevilla, Spain Glioma Cancer Stem-Like Cells (GSCs) are a small subset of CD133+ cells with self-renewal properties and capable of initiating new tumors contributing to Glioma progression, maintenance, hierarchy, and complexity. GSCs are highly res...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
Hui Zhou, Xiaoyan Fu, Qian Li and Ting Niu* Department of Hematology and Research Laboratory of Hematology, West China Hospital, Sichuan University, Chengdu, China Background: Immune checkpoint inhibition therapy with monoclonal antibody against programmed cell death protein 1 (PD-1), including nivolumab and pembrolizumab, has demonstrated powerful clinical efficacy in the treatment of advanced cancers. However, there is no evidence-based systematic review on the safety and efficacy of anti-PD-1 antibody in treating lymphoma. Methods: To evaluate the safety and efficacy of nivolumab/pembrolizumab, we analyzed clin...
Source: Frontiers in Pharmacology - Category: Drugs & Pharmacology Source Type: research
Conclusions This review describes how leukocyte-heparanase can be a double-edged sword in tumor progression; it can enhance tumor immune surveillance and tumor cell clearance, but also promote tumor survival and growth. We also discuss the potential of using heparanase in leukocyte therapies against tumors, and the effects of heparanase inhibitors on tumor progression and immunity. We are just beginning to understand the influence of heparanase on a pro/anti-tumor immune response, and there are still many questions to answer. How do the pro/anti-tumorigenic effects of heparanase differ across different cancer types? Does...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
In conclusion, e-As4S4 holds great potential for an alternative therapeutics in the treatment of breast cancer, due to its unique function of correcting the aggressive microenvironment. Introduction Metastasis is the leading cause of breast cancer mortality, which has been one major challenge in clinical treatment (1). In particular, triple-negative breast cancer (TNBC) is characterized by the absence of estrogen receptors (ER), progesterone receptors (PR) and HER2 receptors, which is one of the most aggressive types of breast cancers, marked by high rates of relapse, visceral metastases and early death (2, 3). The...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
Conclusions MDSC are major players in the immunosuppressive scenario in cancer, thanks to their phenotype heterogeneity and critical interaction with several innate immune cells, thus representing a crucial target in oncology. Here we reviewed the interactions of MDSCs with NK cells. The contribution of key cytokines, chemokines and mediators active in this process have been discussed. We also described the contribution of MDSC on angiogenesis directly or indirectly through interactions with NK and immunosuppressive activities. A parallel of the cancer associated to the decidual counterpart of these cells is discussed, a...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
In this study, we aimed to investigate the potential anti-proliferative and pro-apoptotic activities of SNG in a panel of MM cell lines (U266, IM9, MM1S, and RPMI-8226). SNG treatment of MM cells resulted in a dose-dependent decrease in cell viability through mitochondrial membrane potential loss and activation of caspase 3, 9, and cleavage of PARP. Pre-treatment of MM cells with a universal caspase inhibitor, Z-VAD-FMK, prevented SNG mediated loss of cell viability, apoptosis, and caspase activation, confirming that SNG-mediated apoptosis is caspase-dependent. The SNG-mediated apoptosis appears to be resulted from suppres...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
This study was supported by the Shanghai Sailing Program [grant number 17YF1425200, 2017]; Chinese National Natural Science Funding [grant number 81702249, 2017]; Science and Technology Commission of Shanghai Municipality [grant number 17511103403, 2017]; The funder has no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Conflict of Interest Statement The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Acknowledgments We acknowledge the ex...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
Discussion Suppressor of cytokine signaling 1 is an essential molecule for maintaining immune homeostasis and subverting inflammation. Disorders arising from excess inflammation or SOCS1 deficiency can be potentially treated with SOCS1 mimetics (Ahmed et al., 2015). While SOCS1 has promising potential in many disorders, it should be noted that new targets and actions of SOCS1 are still being discovered and not all the effects of this protein are beneficial in autoimmune diseases and cancer. For instance, SOCS1 degrades IRS1 and IRS2, required for insulin signaling, via the SOCS Box domain, thus, limiting its potential in ...
Source: Frontiers in Pharmacology - Category: Drugs & Pharmacology Source Type: research
This study proposed a pilot study of a new tool for a reliable and accurate stratification of patients with acute leukemia based on an integrative model of leukemia behavior, cell characterization, and clinical features, in addition, to an evaluation of intra-tumor and inter-tumor heterogeneity. Together our approach allows us to introduce an integrative quantitative approach to use zebrafish and tumor characterization as a prediction tool for the behavior of acute leukemia in young adults. Materials and Methods Animal Care and Handling Zebrafish wild-type (A/B and TAB5) adults were raised and maintained according to st...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
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