Human Squamous Cell Carcinoma KB Research Articles

Necrosis of Carcinoma Cells Using<tex>$hboxCo_1-rm xhboxNi_rm xhboxFe_2hboxO_4$</tex>and<tex>$hboxBa_1-rm xhboxSr_rm xhboxFe_12hboxO_19$</tex>Ferrites Under Alternating Magnetic Field

The purpose of this study was to investigate the cell necrosis by the hysteric heating of Co/sub 1-x/Ni/sub x/Fe/sub 2/O/sub 4/ and Ba/sub 1-x/Sr/sub x/Fe/sub 12/O/sub 19/ ferrites under external magnetic field with respect to applications in hyperthermic cancer treatments. Co/sub 1-x/Ni/sub x/Fe/sub 2/O/sub 4/ and Ba/sub 1-x/Sr/sub x/Fe/sub 12/O/sub 19/ ferrites were synthesized by a sol-gel process. Variation of the temperature as a result of hysteresis heating was measured as a function of the exposure time to the external alternating magnetic field at frequencies of 0.1 /spl sim/ 15 MHz. A human squamous cell carcinoma KB cell line was selected to determine the effect of the synthesized ferrites on the destruction of carcinoma cells in vitro using a methylthiazol tetrazolium bromide (MTT) method. When a CoFe/sub 2/O/sub 4/ disc was placed in 0.2 ml of distilled water, the greatest temperature change (/spl Delta/T=29.3/spl deg/C) was observed. More than half of the malignant carcinoma cells were dead after being exposed to the 7-MHz ac magnetic field for 1 h by CoFe/sub 2/O/sub 4/ ferrites, while normal cells survived more than 60% of the time.

Expression and role of phosphodiesterase 3 in human squamous cell carcinoma KB cells.

Phosphodiesterase (PDE) 3s have been characterized in human squamous cell carcinoma KB cells. PDE3 activity was detected in homogenates of KB cells. PDE3A and 3B mRNAs were detected by RT-PCR in RNA from KB cells; the nucleotide sequences of the fragments were identical to those of human PDE3A and 3B. Immunoblotting with anti-PDE3 antibodies detected both PDE3A- and 3B-immunoreactive proteins in KB cells. The PDE3-specific inhibitor, cilostamide, inhibited the proliferation of KB cells. Our results indicate that PDE3s may be important regulators of the growth of KB cells. Therefore, PDE3 inhibitors may be potential new drugs for antiproliferative therapies in squamous cell carcinoma in the head and neck.