Pancreatic ductal adenocarcinoma(PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significa...Pancreatic ductal adenocarcinoma(PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive PDAC.Additional genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling network.Recent exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein(YAP) and WW-domaincontaining transcriptional co-activator with PDZ-binding motif(TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.展开更多
The WW domain-containing oxidoreductase(WWOX) is a tumor suppressor in a variety of cancers, including breast cancer. Reduced WWOX expression is associated with the basal-like subtype and a relatively poor disease-f...The WW domain-containing oxidoreductase(WWOX) is a tumor suppressor in a variety of cancers, including breast cancer. Reduced WWOX expression is associated with the basal-like subtype and a relatively poor disease-free survival rate among breast cancer patients. Though several WWOX partners have been identified, the functional mechanisms of WWOX's role in cancers have not been fully addressed to date. In the current study, we found WWOX suppresses expression of KLF5—an oncogenic transcription factor—at protein level, and suppresses cancer cell proliferation in both bladder and breast cancer cell lines. Furthermore, we demonstrated that WWOX physically interacts with KLF5 via the former's WW domains and the latter's PY motifs. Interestingly, we found the expression of WWOX negatively correlates with KLF5 expression in a panel of breast cancer cell lines. Taken together, we conjecture that WWOX may suppress cancer cell proliferation partially by reducing the expression of KLF5.展开更多
The growth-inhibiting and apoptosis-inducing effects of WW domain-containing oxidoreductase(WWOX) gene on ovarian cancer cell line A2780 were investigated.The full length cDNA of human WWOX gene was amplified from nor...The growth-inhibiting and apoptosis-inducing effects of WW domain-containing oxidoreductase(WWOX) gene on ovarian cancer cell line A2780 were investigated.The full length cDNA of human WWOX gene was amplified from normal human ovary tissues.The correct cDNA of full length WWOX was subcloned into eukaryocytic expression vector pCMV.After introduction of WWOX gene into cancer cells with liposome,the WWOX mRNA and protein level in the cancer cells were detected by reverse transcription polymerase chain reaction(RT-PCR) and immunoblotting.The growth activities of cancer cells were detected by Trypan blue staining.The clone formation assay in soft agar was employed to observe the proliferation of the cancer cells.Apoptosis was examined by DNA ladder and acridine orange-ethidium bromide fluorescent staining.The results showed that 72 h after WWOX gene transfection,the WWOX expression was increased significantly(P<0.01).The growth of ovarian cancer cells was decreased by 16.41% to 38.49%(P<0.01).The clone formation abilities were reduced(P<0.01).Some cancer cells presented the characteristic morphological changes of apoptosis with obvious ladder bands on electrophoresis.The apoptosis rate was(20.7±6.0)%(P<0.01).It was concluded that over-expression of WWOX gene could induce apoptosis and inhibit the growth of ovarian cancer cells,which might be potentially useful in the gene therapy of ovarian cancers.展开更多
文摘Pancreatic ductal adenocarcinoma(PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive PDAC.Additional genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling network.Recent exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein(YAP) and WW-domaincontaining transcriptional co-activator with PDZ-binding motif(TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.
基金supported by National Natural Science Foundation of China (81272930, 81322038, 31260208, and U1132605)the Science and Technological Key Project of Yunnan Province (2012FB185)West Light Foundation of the Chinese Academy of Sciences (to R.L.)
文摘The WW domain-containing oxidoreductase(WWOX) is a tumor suppressor in a variety of cancers, including breast cancer. Reduced WWOX expression is associated with the basal-like subtype and a relatively poor disease-free survival rate among breast cancer patients. Though several WWOX partners have been identified, the functional mechanisms of WWOX's role in cancers have not been fully addressed to date. In the current study, we found WWOX suppresses expression of KLF5—an oncogenic transcription factor—at protein level, and suppresses cancer cell proliferation in both bladder and breast cancer cell lines. Furthermore, we demonstrated that WWOX physically interacts with KLF5 via the former's WW domains and the latter's PY motifs. Interestingly, we found the expression of WWOX negatively correlates with KLF5 expression in a panel of breast cancer cell lines. Taken together, we conjecture that WWOX may suppress cancer cell proliferation partially by reducing the expression of KLF5.
文摘The growth-inhibiting and apoptosis-inducing effects of WW domain-containing oxidoreductase(WWOX) gene on ovarian cancer cell line A2780 were investigated.The full length cDNA of human WWOX gene was amplified from normal human ovary tissues.The correct cDNA of full length WWOX was subcloned into eukaryocytic expression vector pCMV.After introduction of WWOX gene into cancer cells with liposome,the WWOX mRNA and protein level in the cancer cells were detected by reverse transcription polymerase chain reaction(RT-PCR) and immunoblotting.The growth activities of cancer cells were detected by Trypan blue staining.The clone formation assay in soft agar was employed to observe the proliferation of the cancer cells.Apoptosis was examined by DNA ladder and acridine orange-ethidium bromide fluorescent staining.The results showed that 72 h after WWOX gene transfection,the WWOX expression was increased significantly(P<0.01).The growth of ovarian cancer cells was decreased by 16.41% to 38.49%(P<0.01).The clone formation abilities were reduced(P<0.01).Some cancer cells presented the characteristic morphological changes of apoptosis with obvious ladder bands on electrophoresis.The apoptosis rate was(20.7±6.0)%(P<0.01).It was concluded that over-expression of WWOX gene could induce apoptosis and inhibit the growth of ovarian cancer cells,which might be potentially useful in the gene therapy of ovarian cancers.