The video demonstrates an immunofluorescence-based approach for quantifying replication stress in cancer cells. Hydroxyurea-treated cells produce single-stranded DNA, detected through immunofluorescence. The count of green fluorescence foci indicates the level of replication stress in cancer cells.
Protocol
NOTE: The ovarian cancer cell line, OVCAR3, was used in these steps, but this protocol is broadly applicable to multiple other cell lines, including those derived from non-ovarian sources. A schematic of the protocol is shown in Figure 1. 1. Plating the cells Make poly-L-lysine coated coverslips. Add autoclaved 12 mm diameter coverslips to a 50 mL conical tube with poly-L-lysine solution, and place on a rocker for …
Representative Results
Figure 1: IdU labeling schematic. Cells are pulsed with IdU for two population doublings. If any drug treatment is needed, it should be administered after the first population doubling in the presence of IdU. Figure 2: Comparison of the foci signal…
Offenlegungen
The authors have nothing to disclose.
Materials
3% Paraformaldehyde (PFA)
Fisher Scientific
NC0179595
10 g sucrose + 100 mL 10X PBS + water to make volume to 925 mL. Add 75 mL 40% Methanol free PFA, mix, and make aliquots of 50 mL before storage
Storage: Store in -20 °C
5-iodo-2'-deoxyuridine (IdU)
Sigma Aldrich
I7125-5G
MW = 354.10 g/mol.For 10 mM stock: dissolve 3.541 mg IdU to 1 mL 1 N liquid ammonia
Anti-BrdU antibody
BD Biosciences
347580
Storage: Store in 4 °C
Anti-mouse Alexa Fluor Plus 488 secondary antibody
Thermo Scientific
A32766
Light sensitive – keep in dark
Bovine Serum Albumin (BSA)
Sigma Aldrich
A7906-100G
Made by adding specific mass to volume of PBS
Storage: Store in 4 °C
Circular Cover Glass
Electron Microscopy Sciences
72230-01
OVCAR3
ATCC
HTB-161
Growth Media: RPMI supplemented with L-glutamine, 0.01 mg/mL bovine insulin; fetal bovine serum to a final concentration of 20% and 1X Pen Strep
Storage: Freezing Media: growth media + 5% DMSO and stored in -80 °C