Abstract 4227
Background
Tumor-associated macrophages (TAMs) are a major component of innate immunity supporting primary tumor growth and metastasis. Chemotherapy is one of the main treatment strategies for solid tumors, while chemoresistance is the major limitation of the chemotherapy for patients with various types of cancer. A number of evidence indicate that TAMs can accumulate in tumors after chemotherapy and contribute to chemoresistance.
Methods
For the endocytic uptake of EGF we used flow cytometry analysis. Confocal microscopy was used for the analysis of stabilin-1-mediated internalization and endocytic trafficking of EGF in CHO cells and in modeled TAMs differentiated in the presence of conditioned supernatants of breast cancer (MCF-7) and colorectal cancer (Colo206F) cell lines. We performed next-generation sequencing of RNA samples obtained from our modeled TAMs. Validation of sequencing data by real-time PCR was performed for selected genes implicated in the endocytic uptake: DNM3, STX8, DENND1A and EHD1.
Results
For the first time we demonstrated that stabilin-1 ectopically expressed in CHO cells mediates endocytic uptake of EGF, key growth factor stimulating progression of breast and colorectal cancer. In the model of primary human TAMs, we have demonstrated that cisplatin decreases stabilin-1-mediated internalization and endocytic trafficking of EGF, without affecting gene expression of scavenger receptor stabilin-1. Molecular mechanisms of cisplatin effect on TAMs were uncovered using high throughput RNA sequencing. Gene set enrichment analysis identified that cisplatin contributes to defects in endocyting machinery reducing membrane biogenesis and vesicular transport. Significant suppression of DNM3, STX8, DENND1A and EHD1 genes expression by cisplatin was confirmed by RT-PCR.
Conclusions
We suggested that suppression of receptor-mediated clearance of tumor-supportive factors, such as EGF, by chemotherapeutic drugs may potentially lead to the tumor progression and/or relapse as a mechanism of macrophage-mediated chemoresistance. This study was supported by grand RSF №19-15-00151.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
National Research Tomsk State University.
Funding
RSF N19-15-00151.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
3305 - A phase I dose-escalation and expansion trial of intratumorally administered CV8102, alone and in combination with anti-PD-1 in patients with advanced solid tumors
Presenter: Jürgen Krauss
Session: Poster Display session 1
Resources:
Abstract
5353 - Phase 1/2 Study of 9-ING-41, a small molecule selective Glycogen Synthase Kinase-3 Beta (GSK-3β) Inhibitor, as a Single Agent and Combined with Chemotherapy, in Patients with Refractory Hematological Malignancies or Solid Tumors
Presenter: Benedito Carneiro
Session: Poster Display session 1
Resources:
Abstract
3946 - Trial in progress: a Phase I, open-label study of GSK1795091 administered in combination with immunotherapies in participants with advanced solid tumors (NCT03447314).
Presenter: Aaron Hansen
Session: Poster Display session 1
Resources:
Abstract
3449 - Radiographic Phenotyping to Identify Intracranial Disseminated Recurrence in Brain metastases Treated With Radiosurgery Using Contrast-enhanced MR Imaging
Presenter: CheYu Hsu
Session: Poster Display session 1
Resources:
Abstract
4553 - Association between TP53 mutations and efficacy of Osimertinib for brain metastasis from EGFR-mutant lung cancer
Presenter: Lijuan Chen
Session: Poster Display session 1
Resources:
Abstract
4942 - Response assessment of melanoma brain metastases treated by stereotactic radiotherapy or immunotherapy or both: a comparison of RECIST 1.1, RANO and iRANO criteria
Presenter: Emilie Le Rhun
Session: Poster Display session 1
Resources:
Abstract
3529 - Management of multiple brain metastases by Staged SRS focusing on utmost risk lesions
Presenter: shaoqun Li
Session: Poster Display session 1
Resources:
Abstract
5315 - Whole brain radiotherapy plus simultaneous in-field boost versus whole brain radiotherapy plus fractionated stereotactic radiotherapy for multiple brain metastases of non-small cell lung cancer
Presenter: Lu Li
Session: Poster Display session 1
Resources:
Abstract
1116 - 3D based texture analysis serving as potential diagnostic factor in discriminating primary central nervous system lymphoma from metastatic brain tumors: A preliminary study
Presenter: Wen Guo
Session: Poster Display session 1
Resources:
Abstract
5344 - Global trends in population-based survival for 303,169 adults diagnosed with glioblastoma in 44 countries during 2000-2014 (CONCORD-3)
Presenter: Fabio Girardi
Session: Poster Display session 1
Resources:
Abstract