NSC631570 affects MMP9, HENT1, and SPARC expression in cell cultures of pancreatic cancer. Can we use it in combination with gemcitabine/nab-paclitaxel?

Purpose: The chemotherapy as Gemcitabine (GEM) treatment plus Nab-paclitaxel (Nab-pax), in combination with the surgical procedure shown to increase the OS in PDAC patients. Indeed, two molecular factors might be associated with efficacy of Gem/Nab-pax treatment: SPARC and hENT1 genes. Additionally, another marker associated with aggressiveness of PDAC is the Matrix Metallo-Proteinase 9 (MMP9). While, NSC-631570 showed its molecular activity against MMP9 and SPARC in PDAC cell lines (PDAC-CL). Our goal was to investigate the efficacy of NSC-631570 in in vitro model of PDAC, on MMP9, hENT1 and SPARC proteins in preclinical model of PDAC. Materials and methods: Four PTCCs and Two PDAC-CL were used for cytotoxicity study by NSC-631570. Cells were stained by Immunocytochemistry (IHC) for MMP9 and Immunofluorescence (IF) for SPARC. Another part of cells were used in order to extract RNA to perform quantitative PCR analyses for hENT1 and SPARC. Untreated cells served to asses the expression basal levels of markers and no–stained cells were used as negative control for both IHC and IF. We evaluated protein expression by imaging analysis. Results: We found a significant reduction of MMP9 protein expression in both PTCCs and PDAC-CL treated NSC-631570 with respect to their controls (p<0.01). The drug increased significantly the number cells and showed to modify the structure of nuclei with respect to untreated cells (p<0.001). In addition, NSC-631570 up-regulated the mRNA levels of hENT1 in all PDAC models after IC50 exposure. This data is confirmed by DDCt analyses in comparison with housekeeping gene. In particular, the 2ˆ(-DDCt) revealed that treated cells express higher level of hENT1 with respect to non treated cells (mean value 285.93%; p<0.001). Furthermore, SPARC mRNA levels waere up-regulated in 2/4 PTCCs and in 2/2 PDAC-CL. Finally, the concomitant down-regulation of MMP9 and over-expression hENT1 and SPARC genes was observed in 3/6 (66.7%) of PDAC models. Conclusions: New pharmacological approach is a challenge in order to reduce the metastatic behavior of the PDAC and increase the clinical outcome after chemotherapy treatment. NSC-631570 has been shown to modulate the expression of SPARC and hENT1 justifing Gem/Nab-pax therapy in combination with NSC-631570, highlighting its applicability as a promising clinical approach against PDAC.