Study On The Effect And Mechanism Of LncRNA PANDAR In The Senescence-apoptosis Switch Induced By Curcumin In Colorectal Cancer Cells

Colorectal cancer(CRC)is one of the most common malignant tumors in the world.The incidence and mortality of colorectal cancer in China are increasing year by year.It has been found that long noncoding RNAs(lncRNAs)may play multiple roles in tumor progression.However,roles of lncRNAs in chemotherapy for colorectal cancer are not clear.In this paper,the biological functions of lncRNA PANDAR(promoter of CDKN1 A antisense DNA damage activated RNA)in the treatment of colorectal cancer cells with antitumor drug curcumin was studied.We used qRT-PCR technique to detect and compare the expression of PANDAR in colorectal cancerous and paracancerous tissues.The results showed that PANDAR expression was not notably differential in CRC tissues compared with the corresponding tissues.Through the construction of small interference RNA,cell proliferation,cell apoptosis and cell senescence experiments,we found that knockdown of PANDAR did not change the proliferation,apoptosis or senescence of CRC cells.Further experiments showed that low-dose curcumin could induce senescence of CRC cells without affecting cell apoptosis,and could promote the expression of PANDAR.Finally,qRT-PCR and Western blot experiments showed that silencing PANDAR in low-dose curcumin-treated cells increased cell apoptosis and attenuated cell senescence,and it was found that this effect may be accomplished by inducing the expression of PUMA(p53-upregulated modulator of apoptosis).Our study showed that knockdown of lncRNA PANDAR could switch senescence of CRC cells induced by curcumin to apoptosis,which may be potentially valuable in CRC therapy.