Moreover, in breast cancers of transgenic mice, in TNBC PDXs, and in two clinical TNBC samples that express high or low cath-D levels, we found that cath-D expression was inversely correlated with SPARC levels, and detected the SPARC fragments of 34-kDa and 27-kDa only in samples that strongly expressed cath-D. The gene discussed is SPARC; the disease is breast carcinoma.