Cucurbitacin I

Cucurbitacin I is a natural selective inhibitor of JAK2/STAT3, with potent anti-cancer activity. In Vitro:Exposure of the COLO205 cells to Cucurbitacin I significantly decreases cell viability. The anticancer activity of Cucurbitacin I is accomplished by downregulating p-STAT3 and MMP-9 expression^[1].
PE-induced cell enlargement and upregulation of ANF and β-MHC are significantly suppressed by pretreatment of the cardiomyocytes with Cucurbitacin I. Notably, Cucurbitacin I also impaires connective tissue growth factor (CTGF) and MAPK signaling, pro-hypertrophic factors, as well as TGF-β/Smad signaling, the important contributing factors to fibrosis^[2].
Incubation of the Seax cell line with the Jak/Stat3 inhibitor Cucurbitacin I result in a time- and concentration-dependent decrease of P-Stat3 and Stat3. In freshly isolated Sz cells (n=3), Cucurbitacin I induces a concentration-dependent decrease in Stat3 expression whereas P-Stat3 is undetectable. Finally, incubation of freshly isolated Sz cells (n=4) with 30 μM Cucurbitacin I for 6 hours induces apoptosis in the large majority (73-91%) of tumor cells^[3]. In Vivo:No major side effects are noted throughout the study. It is shown that average tumor volumes at the end of the study are as follows: control, 616 mm³ (±130); CQ, 580 mm³ (±107); Cucurbitacin I, 346mm³ (±79); and combination, 220mm³ (±62). The differences in tumor volume between the Cucurbitacin I and control, combination and control, and combination and Cucurbitacin I arms are significant. Furthermore, combination-treated tumors exhibit a significantly lower average tumor weight at study termination than the control. Moreover, there was no effect on the body weights of mice^[4].