Tumor aggressiveness is independent of radiation quality in murine hepatocellular carcinoma and mammary tumor models

Abstract

Purpose

Estimating cancer risk associated with interplanetary space travel is complicated. Human exposure data to high atomic number, high-energy (HZE) radiation is lacking, so data from low linear energy transfer (low-LET) γ-ray radiation is used in risk models, with the assumption that HZE and γ-ray radiation have comparable biological effects. This assumption has been challenged by reports indicating that HZE radiation might produce more aggressive tumors. The goal of this research is to test whether high-LET HZE radiation induced tumors are more aggressive.

Materials and methods

Murine models of mammary and liver cancer were used to compare the impact of exposure to 0.2Gy of 300MeV/n silicon ions, 3 Gy of γ-rays or no radiation. Numerous measures of tumor aggressiveness were assessed.

Results

For the mammary cancer models, there was no significant change in the tumor latency or metastasis in silicon-irradiated mice compared to controls. For the liver cancer models, we observed an increase in tumor incidence but not tumor aggressiveness in irradiated mice.

Conclusion

Tumors in the HZE-irradiated mice were not more aggressive than those arising from exposure to low-LET γ-rays or spontaneously. Thus, enhanced aggressiveness does not appear to be a uniform characteristic of all tumors in HZE-irradiated animals.

Keywords:

• Mammary cancer
• liver cancer
• mouse model
• radiation
• biomarker discovery
• metastasis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by NASA grant [NNX15AK13G].

Notes on contributors

Eshwar B. Udho

Eshwar B. Udho is a Senior Scientist at Promega Corporation.

Shane M. Huebner

Shane M. Huebner is an Assistant Scientist at the University of Wisconsin – Madison.

Dawn M. Albrecht

Dawn M. Albrecht is a Senior Research Specialist at the University of Wisconsin – Madison.

Kristina A. Matkowskyj

Kristina A. Matkowskyj is an Associate Professor at the University of Wisconsin – Madison

Linda Clipson

Linda Clipson is a Researcher at the University of Wisconsin – Madison.

Catigan A. Hedican

Catigan A. Hedican was a Research Assistant at Promega Corporation.

Rachel Koth

Rachel Koth was a Research Assistant at Promega Corporation.

Santina M. Snow

Santina M. Snow is a Research Assistant at the University of Wisconsin – Madison.

Emily L. Eberhardt

Emily L. Eberhardt was an undergraduate research assistant at the University of Wisconsin – Madison.

Devon Miller

Devon Miller was an undergraduate research assistant at the University of Wisconsin – Madison.

Rachel Van Doorn

Rachel Van Doorn was an undergraduate research assistant at the University of Wisconsin – Madison.

Genti Gjyzeli

Genti Gjyzeli was an undergraduate research assistant at the University of Wisconsin – Madison.

Erin K. Spengler

Erin Spengler is an Associate Professor at the University of Wisconsin – Madison.

Douglas R. Storts

Douglas R. Storts is Head of Research at Promega Corporation.

Douglas H. Thamm

Douglas H. Thamm is a Professor at Colorado State University.

Elijah F. Edmondson

Elijah F. Edmondson, DVM PhD, is a veterinary pathologist at Frederick National Laboratory for Cancer Research.

Michael M. Weil

Michael M. Weil is a Professor at Colorado State University.

Richard B. Halberg

Richard B. Halberg is an Associate Professor at the University of Wisconsin – Madison.

Jeffery W. Bacher

Jeffery W. Bacher is a Senior Scientist at Promega Corporation and Adjunct Professor at University of Wisconsin – Madison.