# COX2-Inhibitory and Cytotoxic Activities of Phytoconstituents of _Matricaria chamomilla_ L.
## 3 Results
### Drug Resistance Profiling of Myricetin  
Moreover, we addressed the question of whether myricetin is involved in classical drug resistance phenotypes of ABC-transporters (P-glycoprotein, ABCB5, ABCC1, and ABCG2), as well as oncogenes (EGFR), tumor suppressors (TP53, WT1), and others (heat shock protein HSP90, glutathione S-transferase \(\pi\), and the proliferation rate of the cell lines) (Table 2). We did not observe statistically significant correlations between the log\({}_{10}\)IC\({}_{50}\) values for myricetin and any of the resistance parameters except for GSTP and cellular proliferation rates. This indicates that the effectiveness of myricetin may be limited by these two drug resistance mechanisms, while all other resistance mechanisms to established anticancer drugs may not be relevant for myricetin.  
\begin{table}
\begin{tabular}{l l l l} \hline \hline  & & **Myricetin (log\({}_{10}\)** & **Control Drug (log\({}_{10}\)** \\  & & **IC\({}_{50}\), M)** & **IC\({}_{50}\), M)** \\ \hline
**ABCB1 Expression** & & & Epirubicin \\ \hline
7q21 (Chromosomal & \(r\)-value & \(-0.120\) & **0.447 \({}^{*}\)** \\ Locus of \(ABCB1\) Gene) & \(p\)-value & \(0.207\) & **3.55 \(\times\) 10\({}^{-4}\)\({}^{*}\)** \\ \(ABCB1\) Expression & \(r\)-value & \(-0.124\) & **0.533 \({}^{*}\)** \\ (Microarray) & \(p\)-value & \(0.186\) & **6.82 \(\times\) 10\({}^{-6}\)** \\ \(ABCB1\) Expression & \(r\)-value & \(0.118\) & **0.410** \\ (RT-PCR) & \(p\)-value & \(0.215\) & **1.54 \(\times\) 10\({}^{-3}\)** \\ \hline
**ABCB5 Expression** & & & [PERSON] \\ \hline \(ABCB5\) Expression & \(r\)-value & \(-0.040\) & **0.454 \({}^{*}\)** \\ (Microarray) & \(p\)-value & \(0.384\) & **6.67 \(\times\) 10\({}^{-4}\)\({}^{*}\)** \\ \(ABCB5\) Expression & \(r\)-value & \(0.060\) & **0.402 \({}^{*}\)** \\ (RT-PCR) & \(p\)-value & \(0.330\) & **0.0026 \({}^{*}\)** \\ \hline
**ABCC1 Expression** & & & Vinblastine \\ \hline DNA Gene & \(r\)-value & \(0.059\) & **0.429 \({}^{*}\)** \\ Copy Number & \(p\)-value & \(0.333\) & **0.001 \({}^{*}\)** \\ \(ABCC1\) Expression & \(r\)-value & \(-0.035\) & **0.398 \({}^{*}\)** \\ (Microarray) & \(p\)-value & \(0.402\) & **0.003 \({}^{*}\)** \\ \(ABCC1\) Expression & \(r\)-value & \(0.149\) & 0.299 \\ (RT-PCR) & \(p\)-value & \(0.170\) & **0.036 \({}^{*}\)** \\ \hline
**ABCG2 Expression** & & & Pancratistin \\ \hline \(ABCG2\) Expression & \(r\)-value & \(0.163\) & **0.329 \({}^{*}\)** \\ (Microarray) & \(p\)-value & \(0.120\) & **0.006 \({}^{*}\)** \\ ABCG2 Expression & \(r\)-value & \(-0.127\) & **0.346 \({}^{*}\)** \\ (Western Blot) & \(p\)-value & \(0.177\) & **0.004 \({}^{*}\)** \\ \hline
**EGFR Expression** & & & Erlotinib \\ \hline \(EGFR\) Gene & \(r\)-value & \(0.135\) & \(-0.245\) \\ Copy Number & \(p\)-value & \(0.160\) & **0.029 \({}^{*}\)** \\ \(EGFR\) Expression & \(r\)-value & \(0.133\) & **-0.458 \({}^{*}\)** \\ (Microarray) & \(p\)-value & \(0.164\) & **1.15 \(\times\) 10\({}^{-4}\)\({}^{*}\)** \\ \(EGFR\) Expression & \(r\)-value & \(0.077\) & **-0.379 \({}^{*}\)** \\ (PCR Slot Blot) & \(p\)-value & \(0.291\) & **0.002 \({}^{*}\)** \\ EGFR Expression & \(r\)-value & \(0.166\) & **-0.376 \({}^{*}\)** \\ (Protein Array) & \(p\)-value & \(0.113\) & **0.001 \({}^{*}\)** \\ \hline
**N-/K-/I-RAS Mutations** & & & Melphalan \\ \hline \(TP53\) Mutation & \(r\)-value & \(0.052\) & **0.367 \({}^{*}\)** \\ (cDNA Sequencing) & \(p\)-value & \(0.354\) & **0.002 \({}^{*}\)** \\ \hline \hline \end{tabular}
\end{table}
Table 2: Correlation between the log\({}_{10}\)IC\({}_{50}\) values for myricetin and various mechanisms of multidrug resistance in the NCI panel of tumor cell lines, including ABC-transporter-mediated (P-glycoprotein/ABCB1, ABCB5, ABCC1, and ABCG2), EGFR, RAS, TP53, WT1, HSP90, GST, and the proliferative rate. Bold and \({}^{*}\)\(p\)\(<\)\(0.05\) and \(r\)\(>\)\(0.3\) (or \(r\)\(<\)\(-\)\(0.3\)).