Lack of bands after RNA isolation from MIA PaCa-2 cells is likely due to cell-specific issues or protocol incompatibilities rather than general problems with reagents or equipment, especially if PANC-1 isolation works fine using the same method. MIA PaCa-2 cells may produce lower amounts of RNA, more easily degraded RNA, or have different cell membrane properties that hinder lysis and RNA release. RNase contamination and harsh cell handling can also degrade RNA rapidly, leading to no visible bands on the gel.

Double-check that cells are lysed efficiently and handled gently, use fresh reagents, and ensure all equipment is RNase-free before starting. Try a more sensitive extraction protocol (such as column-based kits or modified TRIzol steps), or increase cell numbers if yield is low. These small changes may resolve the issue with MIA PaCa-2 but are less critical with PANC-1, which appears less sensitive.