Abstract
구강편평상피암종은 말기에서 종종 화학치료요법제들이 유도하는 세포자멸사에 저항성을 보인다. 박테리아의 독에 대한 진전된 이해는 암치료에 대한 새로운 치료전략으로 제기되어지고 있다. 본 연구는 Pseudomonas aeruginosa exotoxin A (PEA)가 세포자멸사 기작을 통해 항암제에 저항성을 보이는 YD-9 구강편평상피암종의 생존율을 현격하게 떨어뜨림을 설명하고 있다. 세포자멸사현상은 핵의 형태학적 변화와 DNA 분절 생성을 통해 입증되었다. PEA는 caspase-3, -6, -9 의 분절과 활성화를 일으켰다. 그리고 이러한 반응들은 caspase 의 기질에 해당하는 poly (ADP-ribose) polymerase (PARP), DFF45, 그리고 lamin A 의 단백질 분해를 야기했다. 사립체 막전위 감소, cytochrome c와 Smac/DlABLO의 사립체로부터 세포질로의 유리, 그리고 AIF의 사립체에서 핵으로 이동 등이 관찰되었다. p53, p21 그리고 <TEX>$14-3-3{\gamma}$</TEX>는 증가되는 반면 cyclin B와 cdc2는 감소되었다. 이상의 결과들을 종합해 보면 PEA는 caspase를 활성화시키고, 사립체에 변화를 야기시키고 더 나아가서 세포주기 유전자를 조절함으로써 항암제에 대한 강한 저항성을 보이는 YD-9 세포에서 세포자멸사를 유도한다. Oral squamous carcinoma (OSC) cells present resistance to chemotherapeutic agents-mediated apoptosis in the late stages of malignancy. Advances in the understanding of bacterial toxins have produced new strategies for the treatment of cancers. It was demonstrated here that Pseudomonas aeruginosa exotoxin A (PEA) significantly decreased the viability of chemoresistant YD-9 cells in the apoptosis mechanism. Apoptotic manifestations were evident through changes in nuclear morphology and generation of DNA fragmentation. PEA treatment induced caspase-3, -6 and -9 cleavage, and activation. These events preceded proteolysis of the caspase substrates poly (ADP-ribose) polymerase (PARP), DNA fragmentation factor 45 (DFF45), and lamin A in YD-9 cells. The reduction of mitochondrial membrane potential, release of cytochrome c and SmacjDlABLO from mitochondria to cytosol, andtranslocation of AlF into nucleus were shown. While p53, p21 and <TEX>$14-3-3{\gamma}$</TEX> were upregulated, cyclin Band cdc2 were downregulated by PEA treatment. Taken together, PEA induces apoptosis in chemoresistant YD-9 cells via activation of caspases, mitochondrial events and regulation of cell cycle genes.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.