Carcinoembryonic Antigen (CEA) and Hepatic Metastasis in Colorectal Cancer: Update on Biomarker for Clinical and Biotechnological Approaches.

BACKGROUND: Carcinoembryonic Antigen (CEA) is a recommended prognostic marker in Colorectal Cancer (CRC) for tumor diagnosis and monitoring response to therapy. High CEA levels are specifically associated with CRC progression and increased levels of the marker are expected to fall following surgical treatment. Due to its role in CRC, CEA has also been explored as a target for cancer therapy and diagnosis approaches. OBJECTIVE: The goal of this work is to highlight the role of CEA in CRC progression and liver metastasis as well as its potential as a biomarker for clinical and biotechnological approaches. METHOD: A literature search of electronic medical and patent databases Pubmed, Scopus, and Science Direct, Google patents, Esp@cenet and United States Patent and Trademark Office (USPTO), was performed. Information was collected in recent publications, including 81 articles besides 13 patents related to different CEA targeting biotechnological approaches for CRC therapy and diagnosis. RESULTS: CEA enhances CRC metastatic potential through many ways. CEA protects metastatic cells from death, changes the microenvironment of sinusoids, promoting the expression of adhesion molecule and malignant cell survival, besides being considered a proangiogenic molecule. Furthermore CEA has also been evaluated as a target in drug delivery systems, photodynamic therapy, radioimmunotherapy, cancer imaging and nanotechnological devices, leading to many patents concerning to development of anti-CEA antibodies or their fragments with potential to target colorectal cancer and liver metastasis cells. CONCLUSION: CEA is already clinically used to monitor CRC patients, and it is a very promising targeting biomarker for multiple biotechnological applications. As far as we know this is the first report on CEA that addresses patents database.

Photodynamic therapy disinfection of carious tissue mediated by aluminum-chloride-phthalocyanine entrapped in cationic liposomes: an in vitro and clinical study.

Photodynamic therapy (PDT) is a technique employed in the treatment of several superficial infections, such as caries. PDT uses a non-toxic drug termed photosensitizer (PS) followed by light irradiation. The cytotoxic effects of the therapy are related to the production of reactive species produced after light activation of a photosensitizer, which reacts with surrounding molecules and disrupts several of the cell's functions. Within this context, this study aimed to develop a clinical protocol involving PDT application mediated by aluminum-chloride-phthalocyanine (AlClPc) entrapped in cationic liposomes against cariogenic bacteria in caries lesions. Cationic liposomes were used to delivery AlClPc preferentially to bacterial cells due to the strong anionic superficial charges of these cell types. The results are represented in two fundamental steps: (1) in vitro evaluation of AlClPc delivery to cariogenic bacteria and pulp cells, as well as its potential phototoxicity; (2) a clinical study involving volunteer patients that were treated with the PDT protocol mediated by AlClPc-cationic liposome. The main results showed that the AlClPc-cationic liposome was preferentially absorbed by bacterial cells compared to eukaryotic dental pulp cells, and it was efficient in the reduction of microbial load from bacterial cultures. In addition, the clinical study showed a mean reduction of 82% of total bacterial in the treated cavities after PDT application. Taken together, the results presented in this study showed that the antimicrobial PDT protocol mediated by cationic liposomes containing AlClPc is safety for clinical application and is efficient in the reduction of bacterial load in caries lesions.

DNA damage and apoptosis induced by Pteridium aquilinum aqueous extract in the oral cell lines HSG and OSCC-3.

BACKGROUND: Bracken fern (Pteridium aquilinum) has been consumed by humans and animals for centuries. However, its consumption is associated with a high incidence of cancer in the upper digestory tract of different species. Although the oral cavity is the first site of contact with ingested toxic substances, the interaction of bracken fern composites with oral cell lines has not yet been studied. METHODS: In order to study the biological responses of oral cells exposed to bracken fern, we evaluated the genotoxic and cytotoxic effects of a bracken fern aqueous extract in oral cell lines. Human submandibular gland (HSG) and human oral epithelium cells (OSCC-3) cells were treated with three different concentrations of the extract. DNA damage was determined by the comet assay, and cellular morphology was examined by light microscopy. Apoptotic changes were evaluated by transmission electron microscopy and TUNEL assay. RESULTS: The comet assay revealed that the extract was genotoxic for both cell lines but the results were not dose-dependent. The morphological and ultrastructural analyses showed that the extract caused conspicuous alterations in both cell types: uncommon chromatin condensation, nuclear picnosis, cellular volume decrease, nuclear envelope disruption, formation of numerous vacuoles of different sizes and apoptotic bodies. The TUNEL assay confirmed apoptosis induction. CONCLUSIONS: These results demonstrate that the extract was cytotoxic to HSG and OSCC-3 cells, and that cellular degeneration occurred mainly by apoptosis. We believe that oral cells could trigger apoptosis after bracken fern induced DNA damage, in order to avoid the malignant transformation.