Avoidance of Cell Death

Cell viability assays detect live cells and can be used to measure the effect of drug treatments on tumor cell proliferation.

Watch this video to learn the procedure for culturing and plating cells for use in cell-based assays.

Cytotoxicity assays detect dead cells and can be used to measure cytotoxic effects of cancer drugs in cell-based screenings.

Apoptosis can be induced in tumors due to elevated levels of oncogene signaling or DNA damage associated with hyperproliferation. However, tumors can also gain the ability to evade apoptosis, resulting in malignancy and resistance to therapy.

In stressed, nutrient-limited environments such as tumors, autophagy is induced to break down organelles and allow cellular material to be recycled and used for biosynthesis and energy metabolism. Autophagy can have opposing effects on tumor cell behavior. In some cases, it serves as a survival mechanism for tumors, protecting tumors from undergoing apoptosis. In other cases, it can also induce apoptosis, resulting in tumor cell death.

A simple, homogeneous autophagy assay enables screening for modulators of autophagic flux in 2D or 3D culture model systems using a plate-reading luminometer.

3D cultures contain gradients of oxygen and nutrients from the exterior to the interior, allowing them to mimic tissue or tumor environments more closely compared to 2D cultures. As a result, 3D culture systems have become the choice model system for cancer drug development. Working with 3D cultures often requires optimization of 2D assay protocols, such as increased shaking and incubation times. More recently, assays specifically designed for use with 3D cell cultures have become available.