Longitudinal Imaging of Liver Cancer Using MicroCT and Nanoparticle Contrast Agents in CRISPR/Cas9-Induced Liver Cancer Mouse Model

Abstract

Introduction: Micro-computed tomography with nanoparticle contrast agents may be a suitable tool for monitoring the time course of the development and progression of tumors. Here, we suggest a practical and convenient experimental method for generating and longitudinally imaging murine liver cancer models. Methods: Liver cancer was induced in 6 experimental mice by injecting clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeats-associated protein 9 plasmids causing mutations in genes expressed by hepatocytes. Nanoparticle agents are captured by Kupffer cells and detected by micro-computed tomography, thereby enabling longitudinal imaging. A total of 9 mice were used for the experiment. Six mice were injected with both plasmids and contrast, 2 injected with contrast alone, and one not injected with either agent. Micro-computed tomography images were acquired every 2- up to 14-weeks after cancer induction. Results: Liver cancer was first detected by micro-computed tomography at 8 weeks. The mean value of hepatic parenchymal attenuation remained almost unchanged over time, although the standard deviation of attenuation, reflecting heterogeneous contrast enhancement of the hepatic parenchyma, increased slowly over time in all mice. Histopathologically, heterogeneous distribution and aggregation of Kupffer cells was more prominent in the experimental group than in the control group. Heterogeneous enhancement of hepatic parenchyma, which could cause image quality deterioration and image misinterpretation, was observed and could be due to variation in Kupffer cells distribution. Conclusion: Micro-computed tomography with nanoparticle contrast is useful in evaluating the induction and characteristics of liver cancer, determining appropriate size of liver cancer for testing, and confirming therapeutic response.

Evaluation of Radiation Sensitivity Differences in Mouse Liver Tumor Organoids Using CRISPR/Cas9-Mediated Gene Mutation

“…The plasmids (60 μg) were prepared and diluted in 2 mL saline. The solution was hydrodynamically injected through the lateral tail vein using a 31-gauge syringe in 5–7 s. 21 Plasmids with Tp53 + Pten , Tp53 + Pten + Nf1 , Tp53 + Pten + Nf2 , Tp53 + Pten + Tsc2 , Tp53 + Pten + Cdkn2a , or Tp53 + Pten + Rb1 sgRNAs were injected into 9–10 mice in each group. Mice were raised in a clean room to observe the development of liver tumors.…”

Research trends and hot spots in global nanotechnology applications in liver cancer: a bibliometric and visual analysis (2000-2022)

“…In the field of primary LC, nanoparticles are modified as highly tumorspecific imaging contrast agents and targeted therapeutic agents (44). In a CRISPR/Cas9-induced LC mouse model, nanoparticle contrast agent-based micro-CT enables longitudinal imaging of appropriate LC size (45). In allogeneic model imaging studies established in LC patients, nanoparticles using rare earth as T2weighted imaging contrast agents were shown to be effective in enhancing the signal difference between LC tissue and normal liver tissue on magnetic resonance imaging (MRI) (46).…”

Inhibition of Ehrlich ascites carcinoma growth by melatonin: Studies with micro-CT

“…Cancer is a multifaceted disease and evidence gathered from proof-of-concept studies over decades of research has revolutionized our understanding about underlying causes of carcinogenesis and metastasis [1]. Tumor growth is known to occur in two distinct phases, known as early and late vascularization phases.…”