No abstract

Treatment with ALA PDT induced pronounced necrosis in tumors only if the light was delivered at a low rate. The treatment prolonged the survival for tumor-bearing animals.

We compared the in vitro effect of boric acid (BA) versus phenylboronic acid (PBA) on the migration of prostate and breast cancer cell lines and non-tumorigenic cells from the same tissues. Treatment at 24 hours with BA (≤500 μM) did not inhibit chemotaxis on fibronectin in any cell line. However, treatment over the same time course with concentrations of PBA as low as 1 μM significantly inhibited cancer cell migration without effecting nontumorigenic cell lines. The compounds did not affect cell adhesion or viability at 24 hours but did alter morphology; both decreased cancer cell viability at eight days. These results suggest that PBA is more potent than BA in targeting the metastatic and proliferative properties of cancer cells.

In recent years, studies with plant compounds have shown both chemotherapeutic and chemopreventive properties. The current study with plant stress hormones (jasmonates) showed growth inhibitory effects in breast cancer cells. Cis-jasmone (CJ) and methyl jasmonate (MJ) inhibited the long-term proliferation of MDA-MB-435 and MCF-7 cells. Cell cycle analysis showed G0/G1 and S-phase arrest with increasing apoptotic population. Cellular signaling studies with MJ showed decreased membrane fluidity and activation of extrinsic and intrinsic apoptotic pathways. Specifically in extrinsic apoptotic pathway increased expression of TNFR1, activation of MAPK and caspase-8 was observed. MJ also decreased the mitochondrial membrane potential and activated caspase-3 in breast cancer cells. In conclusion our results revealed novel signaling mechanism of MJ in breast cancer cells, indicating that MJ could have potential applications for chemotherapeutic purposes.

The results show that ALA-PDT could not prevent tumors from forming if treatment was performed shortly after tumor initiation. This was likely due to inadequate levels of ALA/PpIX in the glioma cells.