fig1

Figure 1. Cell physiologic conditions in an SCLC CTC tumorosphere. This figure shows a microscopic image of a SCLC CTC BHGc10 tumorosphere with a schematic overlay indicating regions of proliferating, quiescent and hypoxic cells. These spheroid structures grow up to diameters of 1-2 millimeters and develop gradients of nutrient and oxygen supply as well as accumulation of metabolic waste products. SCLC: small cell lung cancer; CTC: circulating tumor cell