Using standard curves, we simultaneously analyzed serglycin present in the culture medium of cancer cells and we found that the concentration of serglycin was as follows: A549, 0.86 ± 0.07 μg/mL; NCI-H23, 0.43 ± 0.02 μg/mL; HCC827, 0.82 ± 0.12 μg/mL; MDA-MB-231, 0.6 ± 0.16 μg/mL; and DLD-1, 0.14 ± 0.05 μg/mL (Figure 1(c)). The gene discussed is SRGN; the disease is cancer.