A Better Shot at Understanding Cancer Cells – Selective Plane Illuminative Microscopy (SPIM)

According to a study conducted by Karolinska university hospital, the three dimensional microscopy technology can diagnose cancer tissues in three – dimensions, giving more accurate results than what a two- dimensional study would.

Cancer treatment depends completely on the diagnosis of cancer tissue samples, which are tested in large quantity everyday by pathologists. Wrong diagnosis or any gap present in its understanding can lead to wrong treatment and further implications, as cancer is nothing to be “tried around” with. Today, pathologists use two-dimensional screening methods to assess what stage cancer is at; stages describe how far the tumor has spread, its outreach and future development along with what parts can be indirectly affected by it. This preliminary study decides how the treatment will proceed.

According to a professor at Karolinska institute, Per Uhlen, cancer cells can be separated into sections for selective study. However, with complicated structures like lymph system and blood samples, it becomes difficult to give a detailed and accurate diagnosis.

Traditionally, cancerous cells were studied on glass slides that flattened their structure; not letting scientists to study them in their natural form, hence suppressing many of their properties. However, with the new microscopic technique – Selective plane illuminative microscopy allows them to study cancer cells non-invasively, letting them observe the cell development over the time.

Selective Plane Illuminative Microscopy (SPIM) uses light sheet to highlight the cells from their sides, in a three dimensional structure. It produces results with optimal resolution, which was not previously achieved, and high penetration in cell structure without being invasive. This fluorescence technique reduces photo bleaching, gives dynamic range and that too at high speed, minimizing the time taken to diagnose a tumor, which previously took days and weeks.

In this technique, tumor cells are placed in a collagen block instead of flattening them on glass sheets, and a thin laser beam is passed through the block to make the cells illuminate, revealing details as tiny as up to 300 nanometers. According to a Quantitative Multi scale Cell Imaging study, melanoma cells were studied in a collagen block using this particular technique, it was revealed that these cells formed bigger lumps, called “blebs” which showed a different kind of protein distribution within the tissue. Studying this kind of intricate molecular structure was previously not possible because there was no technology offering sufficient spatial resolution.

The study also tells that currently researchers have little knowledge of how the microenvironment of a tumor cell influences temporal and spatial structure of signaling pathways. The quantitative techniques, which they have now, did provide them with valuable understanding of how protein spatial activity and distribution affects cell behavior, however the quantify cell signaling and how they change their forms, need an unrestrictive environment for studying the sample which was not possible with intrusion of glass sheets in between.

Scientists at Karolinska university hospital studied cancer samples of a patient’s bladder under three-dimensional blood system, which showed how aggressive these cancerous cells actually are. This novel microscopic technique is able to diagnose cancerous cells, which invade muscles that were missed in two-dimensional study of these cells.  Researchers believe that Selective Plane Illuminative Microscopy can help them understand how tumor cells develop in their habitat, interacting with other cells. This would also allow them to understand how cells are signaled and processes like tissue invasion take place.