Role of calcium in apoptosis of HL-60 cells induced by harringtonine

Mechanisms and therapeutic effectiveness of pulsed electromagnetic field therapy in oncology

Cancer is one of the most common causes of death worldwide. Available treatments are associated with numerous side effects and only a low percentage of patients achieve complete remission. Therefore, there is a strong need for new therapeutic strategies. In this regard, pulsed electromagnetic field (PEMF) therapy presents several potential advantages including non-invasiveness, safety, lack of toxicity for non-cancerous cells, and the possibility of being combined with other available therapies. Indeed, PEMF stimulation has already been used in the context of various cancer types including skin, breast, prostate, hepatocellular, lung, ovarian, pancreatic, bladder, thyroid, and colon cancer in vitro and in vivo. At present, only limited application of PEMF in cancer has been documented in humans. In this article, we review the experimental and clinical evidence of PEMF therapy discussing future perspectives in its use in oncology.

Optimized nanosecond pulsed electric field therapy can cause murine malignant melanomas to self-destruct with a single treatment

We have identified a new, nanosecond pulsed electric field (nsPEF) therapy capable of eliminating murine melanomas located in the skin with a single treatment. When these optimized parameters are used, nsPEFs initiate apoptosis without hyperthermia. We have developed new suction electrodes that are compatible with human skin and have applied them to a xenograft nude mouse melanoma model system to identify the optimal field strength, pulse frequency and pulse number for the treatment of murine melanomas. A single treatment using the optimal pulse parameters (2,000 pulses, 100 ns in duration, 30 kV/cm in amplitude at a pulse frequency of 5-7 pulses/sec) eliminated all 17 melanomas treated with those parameters in 4 mice. This was the highest pulse frequency that we could use without raising the treated skin tumor temperature above 40 degrees C. We also demonstrate that the effects of nsPEF therapy are highly localized to only cells located between electrodes and results in very little scarring of the nsPEF-treated skin.

Nitric oxide and calcium ions in apoptotic esophageal carcinoma cells induced by arsenite

AIM: To Quantitatively analyze the nitri oxide (NO) and Ca²⁺ in apoptosis of esophageal carcinoma cells induced by arsenic trioxide (As₂O₃).

METHODS: The cell line SHEEC1, a malignant esophageal epithelial cell induced by HPV in synergy with TPA in our laboratory, was cultured in a serum-free medium and treated with As₂O₃. Before and after administration of As₂O₃, NO production in cultured medium was detected quantitatively using the Griess Colorimetric method. Intracellular Ca²⁺ was labeled by using the fluorescent dye Fluo3-AM and detected under confocal laser scanning microscope (CLSM), which was able to acquire data in real-time enabling Ca²⁺ dynamics of individual cells in vitro. The apoptotic cells were examined under electron microscopy.

RESULTS: Intracellular concentration of Ca²⁺ increased from 1.00 units to 1.09-1.38 units of fluorescent intensity at As₂O₃ treatment and NO products subsequently released from As₂O₃-treated cells increased from 0.98-1.00 × 10^-2μmol·L^-1 up to 1.48-1.52 × 10^-2μmol·L^-1 and maintained in a high level continuously. Finally apoptosis of cells occurred, chromatin being agglutinated, cells shrunk, nuclei became round and mitochondria swelled.

CONCLUSION: Ca²⁺ and NO increased with cell damage and apoptosis in cells treated by As₂O₃. The Ca²⁺ is an initial messenger to the apoptotic pathway. To investigate Ca²⁺ and NO will be a new direction for studying the apoptotic signaling messenger of the esophageal carcinoma cells induced by As₂O₃.