Fig. 5. Relative mRNA level of OGA and HexA in (a) MDA-MB-231, and (b) MHCC-97H cells determined by qPCR. Measuring the fluorescence intensity at 598 nm of (e) HSA/GlcNPr-HHPO (50 µM/50 µM), and (f) HSA/GlcNAc-HHPO (50 µM/50 µM) in MDA-MB-231 and MHCC-97H cell lysates in a working buffer (0.1% BSA, 50 mM NaH₂PO₄, 100 mM NaCl, pH 7.0) with an excitation wavelength of 598 nm. Fluorescence intensity at 598 nm of (c) HSA/GlcNPr-HHPO (50 µM/50 µM) and (d) HSA/GlcNAc-HHPO (50 µM/50 µM) incubated with OGA (1 µg ml⁻¹) in the absence and presence of TMG (21 nM) for 1 h. Fluorescence intensity at 598 nm of (g) HSA/GlcNPr-HHPO (50 µM/50 µM) and (h) HSA/GlcNAc-HHPO (50 µM/50 µM) incubated in the cell lysate of MDA-MB-231 in the absence and presence of TMG (21 nM) for 1 h. Statistical analysis was performed with two-sided Student's t-test.