## 3 Results  
### S. triloba Acetone Extract Significantly Reduces U2 OS and SKOV3 Cell Viability  
The viability of cells exposed to varying doses of _S. triloba_ was determined based on absorbance readings obtained from the MTT assay. Readings obtained after 48 h of incubation were normalized to respective negative controls (untreated cells) and expressed as percentage viabilities. _S. triloba_ acetone extract significantly reduced U2 OS cell viability at all concentrations tested. The highest concentration (250 ug/mL) induced a reduction in viability of more than 50% (Figure 1A). Contrarily, the ethanol extract did not affect U2 OS cell viability at all concentrations tested (Figure S1). Cisplatin, which was utilized as the positive control for U2 OS cells, significantly inhibited cell viability by more than 50% at all concentrations tested (Figure 1B). SKOV3 cells on the other hand exhibited a reduction in cell viability at only the two highest concentrations tested (75 and 150 ug/mL) when treated with _S. triloba_ acetone extract. A drastic decline in SKOV3 cell viability (approximately 82%) was observed when SKOV3 cells were exposed to 150 ug/mL of the acetone extract (Figure 1C). Paclitaxel (SKOV3 positive control) significantly inhibited cell viability at all concentrations tested; reductions in SKOV3 cell viability ranged from approximately 57% to 21% (Figure 1D). Additionally, _S. triloba_ ethanol extract showed no effect on HepG2 cell viability when tested with concentrations ranging from 9.4 to 600 ug/mL for both MTT and trypan blue assays. Accordingly, the ethanol extract demonstrated no effect on HepG2 cell morphology at this concentration range (Figure S2). Since HepG2 cell viability displayed no reduction after _S. triloba_ treatment, we excluded further testing of HepG2 cells in downstream assays. DMSO, which was the solvent used to reconstitute _S. triloba_ extracts exhibited no effect on viability when tested on U2 OS or SKOV3 cells at the highest working concentration (0.2% DMSO) (Figure S3). MTT data were used to determine IC\({}_{50}\) values by generating dose-response curves for respective treatments. All dose-response curves possessed a negative slope, indicating a reduction in cell viability as the extract concentration increased. IC\({}_{50}\) values obtained for U2 OS were 30.210 \(\pm\) 1.180 ug/mL (R\({}^{2}\) = 0.797) and 3.033 \(\pm\) 1.189 ug/mL (R\({}^{2}\) = 0.919) for _S. triloba_ acetone extract and cisplatin treatments respectively (Figure 2A,B). In contrast, IC\({}_{50}\) values obtained for SKOV3 cells were 75.960 \(\pm\) 1.0237 ug/mL (R\({}^{2}\) = 0.890) and 3.148 \(\pm\) 1.197 ug/mL (R\({}^{2}\) = 0.771) for _S. triloba_ acetone extract and paclitaxel treatments respectively (Figure 2C,D). Additionally, with the exception of U2 OS cells treated with the acetone extract, all other experiments possessed Hill Slope magnitudes greater than 1. The greatest Hill Slope magnitude (6.678 \(\pm\) 3.928) was observed when SKOV3 cells were treated with _S. triloba_ acetone extract while the least magnitude (0.8665 \(\pm\) 0.137) was recorded for U2 OS cells treated with _S. triloba_ acetone extract (Table S1). Figure 1: _S. triloba_ acetone extract significantly reduces U2 OS and SKOV3 cell viability. (**A**) U2 OS cell viability after 48 h exposure to _S. triloba_ acetone. The acetone extract significantly reduced U2 OS cell viability at all tested concentrations. (**B**) U2 OS cell viability was significantly reduced by more than 50% after incubation with cisplatin (48 h) at all examined concentrations; cisplatin served as a positive control for U2 OS cells. (**C**) SKOV3 cell viability was significantly reduced when incubated (48 h) with _S. triloba_ acetone extract at both 75 \(\upmu\)g/mL and 150 \(\upmu\)g/mL concentrations. A sharp decline in SKOV3 cell viability (>50%) was observed at the 150 \(\upmu\)g/mL concentration, and this reduction showed statistical significance when compared to the 75 \(\upmu\)g/mL concentration.