In October 2009, a 71-year-old female was diagnosed with a cystic tumor in the tail of the pancreas with an irregular dilatation of the main pancreatic duct in the body and tail of the pancreas. A distal pancreatectom...In October 2009, a 71-year-old female was diagnosed with a cystic tumor in the tail of the pancreas with an irregular dilatation of the main pancreatic duct in the body and tail of the pancreas. A distal pancreatectomy with splenectomy, and partial resection of the duodenum, jejunum and transverse colon was performed. In March 2011, a follow-up computed tomography scan showed a low density mass at the head of the remnant pancreas. We diagnosed it as a recurrence of the tumor and performed a total pancreatectomy for the remnant pancreas. In the histological evaluation of the resected specimen of the distal pancreas, the neoplastic cells formed an acinar and papillary structure that extended into the main pancreatic duct. Mucin5AC, α1-antitrypsin (α-AT) and carcinoembryonic antigen (CEA) were detected in the tumor cells by immunohistochemistry. In the resected head of the pancreas, the tumor was composed of both acinar and ductal elements with a mottled pattern. The proportions of each element were approximately 40% and 60%, respectively. Strongly positive α-AT cells were detected in the acinar element. Some tumor cells were also CEA positive. However, the staining for synaptophysin and chromogranin A was negative in the tumor cells. Ultimately, we diagnosed the tumor as a recurrence of mixed acinar-ductal carcinoma in the remnant pancreas. In conclusion, we report here a rare case of repeated pancreatic resection for multicentric lesions of mixed acinar-ductal carcinoma of the pancreas.展开更多
Recently,there has been significant progress in the development of genetically-engineered mouse(GEM)models.By introducing genetic alterations and/or signaling alterations of human pancreatic cancer into the mouse panc...Recently,there has been significant progress in the development of genetically-engineered mouse(GEM)models.By introducing genetic alterations and/or signaling alterations of human pancreatic cancer into the mouse pancreas,animal models can recapitulate human disease.Pancreas epithelium-specific endogenous Kras activation develops murine pancreatic intraepithelial neoplasia(mPanIN).Additional inactivation of p16,p53,or transforming growth factor-βsignaling,in the context of Kras activation,dramatically accelerates mPanIN progression to invasive pancreatic ductal adenocarcinoma(PDAC)with abundant stromal expansion and marked fibrosis(desmoplasia).The autochthonous cancer models retain tumor progression processes from pre-cancer to cancer as well as the intact tumor microenvironment,which is superior to xenograft models,although there are some limitations and differences from human PDAC.By fully studying GEM models,we can understand the mechanisms of PDAC formation and progression more precisely,which will lead us to a breakthrough in novel diagnostic and therapeutic methods as well as identification of the origin of PDAC.展开更多
Pancreatic ductal adenocarcinoma(PDAC) is a common pancreatic cancer and the fourth leading cause of cancer death in the United States. Treating this life-threatening disease remains challenging due to the lack of eff...Pancreatic ductal adenocarcinoma(PDAC) is a common pancreatic cancer and the fourth leading cause of cancer death in the United States. Treating this life-threatening disease remains challenging due to the lack of effective prognosis, diagnosis and therapy. Apart from pancreatic duct cells, acinar cells may also be the origin of PDAC. During pancreatitis or combined with activating KRasG12 D mutation, acinar cells lose their cellular identity and undergo a transdifferentiation process called acinarto-ductal-metaplasia(ADM), forming duct cells which may then transform into pancreatic intraepithelial neoplasia(Pan IN) and eventually PDAC. During ADM, the activation of mitogen-activated protein kinases, Wnt, Notch and phosphatidylinositide 3-kinases/Akt signaling inhibits the transcription of acinar-specific genes, including Mist and amylase, but promotes the expression of ductal genes, such as cytokeratin-19. Inhibition of this transdifferentiation process hinders the development of Pan IN and PDAC. In addition, the transdifferentiated cells regain acinar identity, indicating ADM may be a reversible process. This provides a new therapeutic direction in treating PDAC through cancer reprogramming. Many studies have already demonstrated the success of switching Pan IN/PDAC back to normal cells through the use of PD325901, the expression of E47, and the knockdown of Dickkopf-3. In this review, we discuss the signaling pathways involved in ADM and the therapeutic potential of targeting reprogramming in order to treat PDAC.展开更多
Aim: To elucidate the anti-apoptotic properties of nuclear factor kappa light-chain-enhancer of activated B cells (NF-κB) and feedback regulation of NF-κB by nuclear factor of kappa light-chain-enhancer of activated...Aim: To elucidate the anti-apoptotic properties of nuclear factor kappa light-chain-enhancer of activated B cells (NF-κB) and feedback regulation of NF-κB by nuclear factor of kappa light-chain-enhancer of activated B-cells inhibitor alpha (IκBα). Methods: We developed an in vitro model of Sjogren’s syndrome by transfecting human salivary gland (HSG) and acinar cells (NS-SV-AC) with a plasmid-encoding IκBαM (pCMV-IκBαM), a degradation-resistant IκBα (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha)-mutant, and examined TNF-induced apoptosis and anti-apoptotic properties of NF-κB. Apoptosis and induction of pro-apoptotic and anti-apoptotic genes were investigated by cDNA arrays, RT-PCR, electrophoretic mobility shift assays, and western blot. Results: In the presence of NF-κB inhibitors, TNF-induced apoptosis was markedly increased in both salivary gland and acinar cells. Increased caspase-3 activity was present in both HSG and NS-SV-AC cells. IκBαM-transfected salivary gland cells were more sensitive to TNF-induced apoptosis than IκBαM-transfected acinar cells. Transcription of pro-apoptotic genes was confirmed in both HSG and NS-SV-AC cells that were transfected with IκBαM. Results from caspase-3 activity assay confirmed previous experiments showing an apoptotic role for NF-κB. Conclusion: Data from gene expression arrays suggest that different mechanisms may operate during TNF-induced apoptosis in salivary gland ductal and acinar cells.展开更多
文摘In October 2009, a 71-year-old female was diagnosed with a cystic tumor in the tail of the pancreas with an irregular dilatation of the main pancreatic duct in the body and tail of the pancreas. A distal pancreatectomy with splenectomy, and partial resection of the duodenum, jejunum and transverse colon was performed. In March 2011, a follow-up computed tomography scan showed a low density mass at the head of the remnant pancreas. We diagnosed it as a recurrence of the tumor and performed a total pancreatectomy for the remnant pancreas. In the histological evaluation of the resected specimen of the distal pancreas, the neoplastic cells formed an acinar and papillary structure that extended into the main pancreatic duct. Mucin5AC, α1-antitrypsin (α-AT) and carcinoembryonic antigen (CEA) were detected in the tumor cells by immunohistochemistry. In the resected head of the pancreas, the tumor was composed of both acinar and ductal elements with a mottled pattern. The proportions of each element were approximately 40% and 60%, respectively. Strongly positive α-AT cells were detected in the acinar element. Some tumor cells were also CEA positive. However, the staining for synaptophysin and chromogranin A was negative in the tumor cells. Ultimately, we diagnosed the tumor as a recurrence of mixed acinar-ductal carcinoma in the remnant pancreas. In conclusion, we report here a rare case of repeated pancreatic resection for multicentric lesions of mixed acinar-ductal carcinoma of the pancreas.
文摘Recently,there has been significant progress in the development of genetically-engineered mouse(GEM)models.By introducing genetic alterations and/or signaling alterations of human pancreatic cancer into the mouse pancreas,animal models can recapitulate human disease.Pancreas epithelium-specific endogenous Kras activation develops murine pancreatic intraepithelial neoplasia(mPanIN).Additional inactivation of p16,p53,or transforming growth factor-βsignaling,in the context of Kras activation,dramatically accelerates mPanIN progression to invasive pancreatic ductal adenocarcinoma(PDAC)with abundant stromal expansion and marked fibrosis(desmoplasia).The autochthonous cancer models retain tumor progression processes from pre-cancer to cancer as well as the intact tumor microenvironment,which is superior to xenograft models,although there are some limitations and differences from human PDAC.By fully studying GEM models,we can understand the mechanisms of PDAC formation and progression more precisely,which will lead us to a breakthrough in novel diagnostic and therapeutic methods as well as identification of the origin of PDAC.
基金Supported by the General Research Fund,Research Grants Council of Hong Kong,No.CUHK462211,No.CUHK462713 and No.14102714the National Natural Science Foundation of China,No.81101888 and No.8142730
文摘Pancreatic ductal adenocarcinoma(PDAC) is a common pancreatic cancer and the fourth leading cause of cancer death in the United States. Treating this life-threatening disease remains challenging due to the lack of effective prognosis, diagnosis and therapy. Apart from pancreatic duct cells, acinar cells may also be the origin of PDAC. During pancreatitis or combined with activating KRasG12 D mutation, acinar cells lose their cellular identity and undergo a transdifferentiation process called acinarto-ductal-metaplasia(ADM), forming duct cells which may then transform into pancreatic intraepithelial neoplasia(Pan IN) and eventually PDAC. During ADM, the activation of mitogen-activated protein kinases, Wnt, Notch and phosphatidylinositide 3-kinases/Akt signaling inhibits the transcription of acinar-specific genes, including Mist and amylase, but promotes the expression of ductal genes, such as cytokeratin-19. Inhibition of this transdifferentiation process hinders the development of Pan IN and PDAC. In addition, the transdifferentiated cells regain acinar identity, indicating ADM may be a reversible process. This provides a new therapeutic direction in treating PDAC through cancer reprogramming. Many studies have already demonstrated the success of switching Pan IN/PDAC back to normal cells through the use of PD325901, the expression of E47, and the knockdown of Dickkopf-3. In this review, we discuss the signaling pathways involved in ADM and the therapeutic potential of targeting reprogramming in order to treat PDAC.
文摘Aim: To elucidate the anti-apoptotic properties of nuclear factor kappa light-chain-enhancer of activated B cells (NF-κB) and feedback regulation of NF-κB by nuclear factor of kappa light-chain-enhancer of activated B-cells inhibitor alpha (IκBα). Methods: We developed an in vitro model of Sjogren’s syndrome by transfecting human salivary gland (HSG) and acinar cells (NS-SV-AC) with a plasmid-encoding IκBαM (pCMV-IκBαM), a degradation-resistant IκBα (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha)-mutant, and examined TNF-induced apoptosis and anti-apoptotic properties of NF-κB. Apoptosis and induction of pro-apoptotic and anti-apoptotic genes were investigated by cDNA arrays, RT-PCR, electrophoretic mobility shift assays, and western blot. Results: In the presence of NF-κB inhibitors, TNF-induced apoptosis was markedly increased in both salivary gland and acinar cells. Increased caspase-3 activity was present in both HSG and NS-SV-AC cells. IκBαM-transfected salivary gland cells were more sensitive to TNF-induced apoptosis than IκBαM-transfected acinar cells. Transcription of pro-apoptotic genes was confirmed in both HSG and NS-SV-AC cells that were transfected with IκBαM. Results from caspase-3 activity assay confirmed previous experiments showing an apoptotic role for NF-κB. Conclusion: Data from gene expression arrays suggest that different mechanisms may operate during TNF-induced apoptosis in salivary gland ductal and acinar cells.
