The use of bacteria in the treatment of cancer has a long and interesting history. The use of live bacteria in this way however has a number of potential problems including toxicity. Purified low molecular weight bacterial proteins have therefore been tested as anticancer agents to avoid such complications. Oral cancer is a widely occurring disease around the world and these lesions are typically very resistant to anticancer agents. In our present study we investigated the effects of purified recombinant azurin from Pseudomonas (P.) aeruginosa against YD-9 (p53-positive) human oral squamous carcinoma cells. Azurin showed cytotoxic effects against these cells in a dose dependent manner. The cell death accompanied by this treatment was found to be characterized by chromatin condensation and apoptotic bodies. Azurin treatment was further found to increase the expression of p53 The stabilization of p53 and induction of apoptosis in YD-9 cells by azurin suggests that it has potentially very strong anticancer properties in oral squamous carcinoma.
Antineoplastic Agents ; Apoptosis ; Azurin ; Bacteria ; Bacterial Proteins ; Carcinoma, Squamous Cell ; Cell Death ; Chromatin ; Humans ; Molecular Weight ; Mouth Neoplasms ; Pseudomonas ; Pseudomonas aeruginosa

The use of bacteria in the treatment of cancer has a long and interesting history. The use of live bacteria in this way however has a number of potential problems including toxicity. Purified low molecular weight bacterial proteins have therefore been tested as anticancer agents to avoid such complications. Oral cancer is a widely occurring disease around the world and these lesions are typically very resistant to anticancer agents. In our present study we investigated the effects of purified recombinant azurin from Pseudomonas (P.) aeruginosa against YD-9 (p53-positive) human oral squamous carcinoma cells. Azurin showed cytotoxic effects against these cells in a dose dependent manner. The cell death accompanied by this treatment was found to be characterized by chromatin condensation and apoptotic bodies. Azurin treatment was further found to increase the expression of p53 The stabilization of p53 and induction of apoptosis in YD-9 cells by azurin suggests that it has potentially very strong anticancer properties in oral squamous carcinoma.
Antineoplastic Agents ; Apoptosis ; Azurin ; Bacteria ; Bacterial Proteins ; Carcinoma, Squamous Cell ; Cell Death ; Chromatin ; Humans ; Molecular Weight ; Mouth Neoplasms ; Pseudomonas ; Pseudomonas aeruginosa

OBJECTIVETo investigate the effects of recombinant AZURIN protein of P. aeruginosa on growth and apoptosis of U2OS cells.

METHODSThe AZURIN gene was amplified from the genome of P.aeruginosa by PCR, and cloned into prokaryotic expression vector pQE30. The soluble AZURIN protein was expressed in E. coli cells M15, then purified and refolded. After treatment of AZURIN, the cell cycle, proliferation and apoptosis were determined by morphological observation, MTT assay, flow cytometry(FCM) and DNA fragmentation assay. Mitochondrial membrane potential(DeltaPsim) was measured by FCM.

RESULTSThe purity of recombinant protein AZURIN reached to 99.1%. Proliferation of U2OS cells were significantly inhibited 12 h after AZURIN (100-200 mg/L) treatment. Apoptosis peak and DNA ladder were observed. Mitochondrial membrane potential decreased gradually from 12 h to 72 h after AZURIN treatment.

CONCLUSIONThe recombinant AZURIN inhibit the growth of the human osteosarcoma U2OS cells and inducs apoptosis in vitroìwhich may be associated with the decrease of mitochondrial membrane potential.

Apoptosis ; drug effects ; Azurin ; genetics ; pharmacology ; Bone Neoplasms ; pathology ; therapy ; Cell Proliferation ; drug effects ; Humans ; Osteosarcoma ; pathology ; therapy ; Recombinant Proteins ; genetics ; pharmacology ; Tumor Cells, Cultured

PURPOSE: Surgical therapy is the primary treatment for oral cancer, but it can cause facial distortion. Therefore, if anticancer drugs are effective against oral cancer, they may be used preferentially. However, oral squamous carcinoma cells (OSCCs) are resistant to these drugs, so finding a way to enhance the sensitivity of these cells to anticancer drugs is important. The bacterial protein azurin is known to selectively enter cancer cells and induce apoptosis. In this study, we show the anticancer effect of azurin in OSCC. MATERIALS AND METHODS: OSCC cell line (YD-9) was subjected to azurin treatment. Cell viability, morphology and protein expression levels were monitored after treatment of azurin. Cells were also subjected to combination treatment of azurin with either 5-fluorouracil or etopside. RESULTS: Azurin-treated cells showed decreased cell viability accompanied by apoptotic phenotypes including morphological change, DNA breakage, and increases in p53 and cyclin B1 protein levels. Combination treatment of azurin with other anti-tumor agents caused an increase in sensitivity to anticancer drugs in azurin-treated YD-9 cells. CONCLUSION: Azurin has a strong synergistic anticancer effect on oral cancer cells when it is used along with anticancer drugs.
Antineoplastic Agents/*administration & dosage ; Apoptosis/drug effects ; Azurin/*administration & dosage/genetics ; Carcinoma, Squamous Cell/*drug therapy/metabolism/pathology ; Cell Line, Tumor ; Cyclin B1/metabolism ; Drug Synergism ; Etoposide/administration & dosage ; Fluorouracil/administration & dosage ; Humans ; Mouth Neoplasms/*drug therapy/metabolism/pathology ; Tumor Suppressor Protein p53/metabolism