Replication of patient specific circulating tumor cells on a microfibrous filter for drug screening

Personalized medicine in cancer treatment has the potential to enhance therapeutic efficacy while simultaneously reducing adverse effects. Molecular characterization of circulating tumor cells (CTCs) offers invaluable insight into metastatic tumor heterogeneity, making them a perfect candidate for metastatic cancer drug screening. However, they are extremely rare. This study presents the development of melt-electrowritten membrane filters designed for the capture, culture, and drug testing of CTCs. By varying the collector speeds, filters with optimized pore sizes and polymer densities were produced, enabling selective capture of CTCs while minimizing co-capture of white blood cells. Biocompatibility tests showed that the filter supported the proliferation of multiple cancer cell lines. The filter successfully captured and cultured colorectal cancer patient-derived CTC44 and CTC45 cells, which formed 3D clusters observable over several weeks. Drug testing with chemotherapeutic agents 5-fluorouracil/oxaliplatin (FOX) and 5-fluorouracil/irinotecan (FIRI) revealed that CTCs in 3D clusters on the filters exhibited significantly higher drug resistance compared to 2D monolayers. These findings demonstrate the potential of the filter as a versatile platform for studying CTC biology and for screening anticancer drugs, providing a more physiologically relevant environment than traditional 2D cultures.