Lycorine, a natural alkaloid extracted from the Amaryllidaceae plant family, was reported to various physiological and pharmacological effects including anti-cancer activity. Nevertheless, there is no report of the anticancer effect of lycorine in oral cancer cells. The effects of lycorine on cell proliferation and apoptosis were examined through trypan blue exclusion assay, 4’-6-diamidino-2-phenylindole (DAPI) stain, Live/Dead assay, Western blot analysis and RT-PCR. Lycorine suppressed cell viability and induced apoptosis in MC3 and HSC-3 cell lines. Lycorine decreased survivin protein but did not affect its mRNA. It regulated survivin through accelerating protein degradation in a time-dependent manner although neither proteasome nor lysosome was not associated with lycorine-mediated protein degradation. Collectively, our results suggest that lycorine may be a potential therapeutic anti-cancer drug candidate for the treatment of human oral cancer.

Rushton bodies are known to be the aberrant keratinization and calcification in the epithelium of odontogenic cyst, which are similar to the features of calcifying odontogenic cyst and pilomatricoma. However, the pathogenetic mechanism of keratinization and calcification of Rushton bodies has not been clearly elucidated. Here, a case of Rushton bodies found in dentigerous cyst was examined by immunohistochemical method using antisera of PCNA, pAKT, HIF, PIM1, and PARP. The globular keratinization in lamellate fashion showed weak birefringency under polarizing microscope, and the Rushton bodies frequently underwent the dystrophic calcification. The polygonal keratinocytes of Rushton bodies were strongly positive for HIF and PARP, and the cyst epithelium was diffusely positive for pAKT and PIM1. Particularly, the cyst epithelium was hyperplastic and focally invaginated into cyst wall with positive reaction of PCNA. These findings may indicate the active response of odontogenic epithelium against the apoptotic stress of the cyst, producing the globular keratinization and irregular calcification in the polygonal keratinocytes. Therefore, it is presumed that the lamellate keratinization and dystrophic calcification of Rushton bodies are aberrant products of retrograding keratinocytes slowly undergoing apoptotic progresses similar to the phenomena of the ghost cells in calcifying odontogenic cyst and pilomatricoma, and also may have a potential for oncogenic proliferation.

In this study, we aimed to determine whether the evaluated markers of cell death could be found at particular developmental stages of normal porcine in vitro fertilization (IVF) embryos. We investigated the characteristics of spontaneous and induced apoptosis during preimplantation development stages of porcine IVF embryos. In experiment 1, to induce apoptosis of porcine IVF embryos, porcine IVF embryos at 22h post insemination were treated at different concentration of actinomycin D (0, 5, 50 and 500 ng/ml in NCSU medium). Treated embryos were incubated at in 5% , 5% for 8h, and then washed to NCSU medium and incubated until blastocyst (BL) stage. We examined cleavage rate at 2days and BL development rate at 7days after in vitro culture. A significantly lower rate of cleavage was found in the 500 ng/ml group compared to others (500 ng/ml vs. 0, 5, 50 ng/ml; 27.8 % vs. 50.0%, 41.2%, 35.9%), and BL formation rate in 500 ng/ml was lower than that of others (500 ng/ml vs. 0, 5, 50 ng/ml; 8.0% vs. 12.6%, 11.2%, 12.6%). In experiment 2, to evaluate apoptotic cells, we conducted TUNEL assay based on morphological assessment of nuclei and on detection of specific DNA degradation under fluorescence microscope. This result showed that apoptosis is a normal event during preimplantation development in control group (0 ng/ml actinomycin D). A high number of BL derived control group contained at least one apoptotic cell. Actinomycin D treated BLs responded to the presence of apoptotic inductor by significant decrease in the average number of blastomeres and increase in the incidence of apoptotic cell death. In 500 ng/ml group, the incidence of apoptosis increased at 4-cell stage and later. This result suggested that apoptosis is a process of normal embryonic development and actinomycin D is useful tool for the apoptosis study of porcine preimplantation embryos.

급성전골수구성 백혈병(Acute promyelocytic leukemia, APL)은 혈액암의 일종으로 치료의 성적이 좋지 않 을 뿐 아니라 항암요법과 병행 하였을 경우 큰 효과를 보이는 것으로 알려져 있는 방사선 치료를 병행함에 도 불구하고 정상세포에도 작용하여 부작용을 초래한다. 본 연구에서는 이러한 부작용을 감소시키기 위하 여 감마선을 TNF-α와 같이 처리하였을 경우 정상세포와 암세포의 세포 죽음에 어떠한 영향을 미치는지 확 인하였다. HL-60 세포는 APL 세포주로서 사용하였고 DMSO를 처리하여 분화시킨 HL-60 세포는 정상과립 구의 성질을 나타내어 정상대조군으로 이용하였다. 그 결과 TNF-α와 함께 감마선을 처리한 HL-60 세포에 서만 세포독성효과를 나타내었고 세포자멸사를 유도하여 세포가 죽음에 이르게 하였다. 결론적으로 TNF-α 는 항암치료의 부작용을 없애기 위해 저농도 감마선 치료 시 함께 사용하여 암 세포의 제거를 증가시켜 암 의 치료효율을 높일 수 있는 유효물질로 사료된다.