Basic Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 21, 2018; 24(43): 4880-4892
Published online Nov 21, 2018. doi: 10.3748/wjg.v24.i43.4880
Establishment, functional and genetic characterization of three novel patient-derived rectal cancer cell lines
Michael Gock, Christina S Mullins, Carina Bergner, Friedrich Prall, Robert Ramer, Anja Göder, Oliver H Krämer, Falko Lange, Bernd J Krause, Ernst Klar, Michael Linnebacher
Michael Gock, Ernst Klar, Department of General Surgery, University Medical Center, Rostock 18055, Germany
Christina S Mullins, Michael Linnebacher, Section of Molecular Oncology and Immunotherapy, University Medical Center, Rostock 18055, Germany
Carina Bergner, Bernd J Krause, Department of Nuclear Medicine, University Medical Center, Rostock 18055, Germany
Friedrich Prall, Institute of Pathology, University Medical Center, Rostock 18055, Germany
Robert Ramer, Institute of Pharmacology, University Medical Center, Rostock 18055, Germany
Anja Göder, Oliver H Krämer, Institute of Toxicology, University Medical Center Mainz, Mainz 55131, Germany
Falko Lange, Oscar-Langendorff-Institute of Physiology, University Medical Center, Rostock 18055, Germany
Author contributions: Gock M, Lange F, Krause BJ and Linnebacher M designed research; Mullins CS, Prall F, Ramer R, Göder A and Lange F performed research; Gock M, Prall F, Krämer OH, Lange F, Krause BJ and Linnebacher M analyzed and reviewed data; Gock M, Bergner C and Klar E provided materials necessary to perform the experiments; Gock M and Linnebacher M wrote the manuscript; Mullins CS, Krämer OH, Lange F and Krause BJ contributed parts of the manuscript and critically reviewed the final version of the manuscript.
Supported by the German Research Foundation to Oliver H Krämer, No. KR 2291/7-1.
Institutional animal care and use committee statement: All procedures were approved by Ethikkommission an der Medizinischen Fakultät der Universität Rostock (reference number II HV 43/2004) in accordance with generally accepted guidelines for the use of human material.
Conflict-of-interest statement: To the best of our knowledge, no conflict of interest exists.
Data sharing statement: No additional data to share.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Institutional review board statement: This study was reviewed and approved by Ethikkommission an der Medizinischen Fakultät der Universität Rostock, Germany.
Correspondence to: Michael Linnebacher, PhD, Postdoc, Research Scientist, Department of General Surgery, Section of Molecular Oncology and Immunotherapy, University Medical Center, Schillingallee 35, Rostock 18055, Germany. michael.linnebacher@med.uni-rostock.de
Telephone: +49-381-4946043 Fax: +49-381-4946002
Received: August 3, 2018
Peer-review started: August 3, 2018
First decision: October 8, 2018
Revised: October 22, 2018
Accepted: November 2, 2018
Article in press: November 2, 2018
Published online: November 21, 2018
ARTICLE HIGHLIGHTS
Research background

It is well known that ultra-low passage and in-depth characterized patient-derived tumor models are highly desirable for basic research and for predicting individual responses to current or novel therapy regimens.

Research motivation

To establish individual tumor models of rectal cancer from patient-derived tumor samples to gain further insights into the biological behavior of rectal cancer.

Research objectives

Main objective of the study was the establishing and profound characterization of new patient-derived rectal cancer cell lines with corresponding patient-derived xenograft models that allow testing of drug response, translational and basic research.

Research methods

Establishment of cell lines could be achieved by direct in vitro culturing and in vivo xenografting with following in vitro culturing. Profound analysis of morphological features, invasive and migratory behavior, phenotype, molecular profile including mutational analysis, and protein expression was done. Responsiveness to current chemotherapeutic drugs was evaluated and sensitivity to radiation and combined radio-chemotherapy was examined. At last the positron emission tomography (PET) tracers 18F-fluorodeoxyglucose (FDG) and 18F-fluorothymidine were used to assess glucose metabolism and proliferation activity respectively.

Research results

Three individual ultra-low passage rectal cancer cell lines could be established. In vitro and in vivo experiments demonstrated that all cell lines retained their malignant properties. Molecular analysis classified all three cell lines as sporadic type (CIMP-0/non-MSI-H). Mutational analysis revealed an individual mutational profile of each cell line (HROC126: APCwt, TP53wt, KRASwt, BRAFwt, PTENwt; HROC239 T0 M1: APCmut, P53wt, KRASmut, BRAFwt, PTENmut and HROC284Met: APCwt, P53mut, KRASmut, BRAFwt, PTENmut). The cell lines demonstrated a heterogeneous response to chemotherapy, radiation and combined radio-chemotherapy. Interestingly, analysis of glucose metabolism showed a markedly reduced uptake of the PET tracer 18F-FDG after combined radio-chemotherapy of all three cell lines.

Research conclusions

Taken together, this study describes the development and in-depth characterization of three patient-derived rectal cancer cell lines that could be established from fresh patients´ tumor samples for the first time. These powerful matched in vitro and in vivo models provide useful tools not only to perform basic research to better understand the biology of rectal cancer, but also to test and establish novel therapy regimens.

Research perspectives

This descriptive study exemplifies the methodology and characterization of rectal cancer cell lines obtained directly from patients´ tumor material. This is an important step to extend the abilities of personalized tumor therapy in the near future.