Tumor cells circulating in the blood are the 'germ cells' of breast cancer metastases. They are very rare and could not be propagated in the culture dish until now, which made research into therapy resistance difficult. A team has now succeeded for the first time in cultivating stable tumor organoids directly from blood samples of breast cancer patients. Using these mini-tumors, the researchers were able to decipher a molecular signaling pathway that ensures the cancer cells' survival and resistance to therapy. With this knowledge, the team was able to develop an approach to specifically eliminate these tumor cells in lab experiments.
