Mikala Egeblad observed the action film of tumour cells by recording their landscapes inside live mice. In the previous study, cells stayed still, frozen on microscope slides, but now viewing them in a living animal brings cells to life. “You turn on the microscope and look in the live mouse and suddenly these same cells are running around like crazy,” says Egeblad, a cancer researcher at Cold Spring Harbor Laboratory in New York. “It really changed my thinking.”

Novel technique offer the chance to spy on the action of individual tumour cells, and investigators thereby utilize relative clues to hypothesis about how cancers grow ,spread and resist treatment. As an promising approach, Tracking Cancer in Live Animals over Time(TCLAT, also called intravital imaging) allows biologists to piece together timelines for key cellular and molecular events, and zoom in some lesion cells that drive the disease or resist treatment.

Intravital imaging involves focusing powerful microscopes directly onto exposed tissue in a live mouse. Microscopy technology, In combination with markers, make this approach powerful. A growing library of molecular makers are available to enhance the color identification and enable researchers to visualize different types of cells and structure, such as immune-system cells.

Recording cancer response to drug

Some scientists are using intravital imaging to track cancer drugs in the body, and to explore why some drug treatments fail. Cancer biologists typically test the effect of chemotherapies in vivo by measuring changes in cancer growth and size in mice. Intravital imaging gives a more direct view, revealing which cells in a lesion take up the drugs, and whether those cells live or die.

Egeblad and her team have made films of doxorubicin, a naturally fluorescent cancer drug, as it infiltrated mammary tumours in mice. They were surprised by the degree of variability — even within small regions of the tumour — in the amount of the drug that got into the cells, and in the number of cells that died.

Viewing action film of tumour cells help aware that the microenvironment, not just genetics, can influence cancer. The further study is an opportunity to reply the questions with deep and  broad insights: how do different components of the tumour and its environment co-evolve?

References:

1. Intravital microscopy through an abdominal imaging window reveals a pre-micrometastasis stage during liver metastasis. Sci Transl Med. 2012 Oct 31;4(158):158ra145.

2. Tumor microenvironment of metastasis in human breast carcinoma: a potential prognostic marker linked to hematogenous dissemination. Clin Cancer Res. 2009 Apr 1;15(7):2433-41.