This indicates that bLf in its oligomeric state retains its ability to interact with receptors and is taken up by the cells in time dependent fashion, although further investigations are needed to determine the receptor-ligand interactions completely. This was further confirmed by studying the release of caspase-3, considered as the final executioner enzyme in the apoptotic pathway. Treatment with HMW-bLf induced a statistically significant increase in the levels of caspase-3 secretion in both MDA-MB-231 and SW480 cells, thereby confirming the induction of cell death by apoptosis. In both SW480 and MDA-MB-231 cells, HMW-bLf treatment significantly up-regulated caspase-3 levels, and in SW480 cells the effect was also significant when compared with control Fe-bLf at 3200 mg mL-1. The rapid internalization of HMW-bLf into the cytoplasm and nuclei of cancer cells seems to lead to the initiation of gene transcription within the cell to trigger apoptotic signals thereby, resulting in cell death via apoptosis. We and other researchers have also shown that internalization of NM-bLf into the cell and nucleus can regulate gene transcription of its receptors, cytokines such as transforming growth factor-b and survivin. bLf has been shown to activate both extrinsic and Cloxacillin Sodium intrinsic apoptotic pathways through activation of different caspases. To confirm the results obtained using the caspase-3 activity assay, Western blot was performed for cleaved caspase-3, which is the active form of the apoptosis activator enzyme. Both SW480 and MDA-MB-231 cells show upregulation of the cleaved caspase-3 expression upon treatment with HMW-bLf. Especially, high expression of cleaved caspase-3 is seen in the 3200 mg mL21 treatments of both Fe-bLf and HMW-bLf in MDA-MB-231 and with 1600 mg mL 21 in SW480. This indicates the ability HMW-bLf to induce apoptosis by activating caspase-3. We have identified its unprecedented and interesting properties. HMW-bLf besides having molecular and structural similarities to Apo-bLf in terms of iron content also retains its antibody, and receptor binding properties. It possesses Voglibose unique features such as higher thermal stability and better resistance against gut enzyme digestion than other forms of bLf monomer.