BACKGROUND Helicobacter pylori(H.pylori)eradication treatment for primary gastric mucosaassociated lymphoid tissue(MALT)lymphoma has already been established.However,t(11;18)(q21;q21)/API2-MALT1 translocation-positive...BACKGROUND Helicobacter pylori(H.pylori)eradication treatment for primary gastric mucosaassociated lymphoid tissue(MALT)lymphoma has already been established.However,t(11;18)(q21;q21)/API2-MALT1 translocation-positive lesions are a type of primary gastric MALT lymphoma in which a response to eradication treatment is difficult to achieve.In addition,trisomy 18 may be associated with diffuse large B-cell lymphoma(DLBCL)transformation of gastric MALT lymphoma.CASE SUMMARY A 66-year-old man was diagnosed with MALT lymphoma in the ascending colon by colonoscopy and biopsy.Two years later,esophagogastroduodenoscopy revealed chronic atrophic gastritis that was positive for H.pylori,and eradication treatment was administered.Two years and nine months later(at the age of 70),a new ulcerative lesion suggestive of MALT lymphoma appeared in the gastric body,and six months later,a similar lesion was also found in the fundus.One year later(4 years and 3 months after H.pylori eradication),at the age of 72,the lesion in the gastric body had become deeper and had propagated.A biopsy revealed a pathological diagnosis of DLBCL.Both MALT lymphoma lesions in the ascending colon and DLBCL lesions in the stomach were positive for the t(11;18)(q21;q21)/API2-MALT1 translocation,and trisomy 18q21 was also detected.After 6 courses of R-CHOP(rituximab,cyclophosphamide,doxorubicin,vincristine and prednisone)chemotherapy,all of the above lesions disappeared[complete remission(CR)],and CR has been maintained for more than 3 years.In addition,both the colonic and gastric lesions were proven to have the same clonality.CONCLUSION Because the patient had a MALT1 translocation with trisomy 18q21,it was thought that this gastric MALT lymphoma developed independently of H.pylori infection and progressed.展开更多
Upon growth factor stimulation, the scaffold protein, Gabl, is tyrosine phosphorylated and subsequently the adaptor protein, Crk, transmits signals from Gabl. We have previously shown that Crk overexpression, which is...Upon growth factor stimulation, the scaffold protein, Gabl, is tyrosine phosphorylated and subsequently the adaptor protein, Crk, transmits signals from Gabl. We have previously shown that Crk overexpression, which is detectable in various human cancers, induces tyrosine phosphorylation of Gabl without extracellular stimuli. In the present study, the underlying mechanisms were further investigated. Mutational analyses of CrkII demonstrated that the SH2 domain, but not the SH3（N） or the regulatory Y221 residue of CrkII, is critical for the induction of Gabl- Y307 phosphorylation. SH2 mutation of CrkII also decreased the interaction with Gabl. In GST pull-down assay, Crk-SH2 bound to wild-type Gahl, whereas Crk-SH3（N） interacted with the Gabl mutant, which lacks the clus- tered tyrosine region （residues 242-410）. Tyrosine phosphorylation of Gabl was induced by all Crk family proteins, but not other SH2-containing signalling adaptors. Src-family kinase inhibitor, PP2, abrogates Crk-induced tyrosine phosphorylations of Gabl. Y307 phosphorylation was undetectable in fibroblasts lacking Src, Yes, and Fyn, even upon overexpression of Crk, whereas cells lacking only Yes and Fyn still contained Gabl with phosphorylated Y307. Furthermore, Crk induced the phosphorylation of Src-Y416; accordingly the interaction between Crk and Csk was increased. The Gabl-Y307F mutant failed to localize near the plasma membrane even upon HGF stimulation and decreased cell migration. Moreover, Gabl-Y307F disturbed the localization of Crk, FAK, and paxillin, which are the typical components of focal adhesions. Taken together, these results indicate that Crk facilitates tyrosine phosphory- lation of Gabl-Y307 through Src, contributing to the organization of focal adhesions and enhanced cell migration, thereby possibly promoting human cancer development.展开更多
Objective： The mucus production is an indicator for the histological grade of mucinous epithelial ovarian cancer （mEOC）. In our previous study, Crk expression was targeted in the human ovarian mucinous adenocarcino...Objective： The mucus production is an indicator for the histological grade of mucinous epithelial ovarian cancer （mEOC）. In our previous study, Crk expression was targeted in the human ovarian mucinous adenocarcinoma cell line MCAS through RNA interference, resulting in the establishment of Crk knock down cells. These cells exhibited decreased tumorigenic potential both in vitro and in vivo. The purpose of this study was to investigate if there is any change in the capability of forming mucus in these Crk knock down cells. Methods： Cytoplasmic periodic acid Schiff （PAS） staining and particle excluding assay were conducted to assess the mucus formation within and around cells, respectively. Additionally, the amount of mucus formed in tumor lumps from nude mice model was measured following HE and PAS staining. Results： The increased mucus production in Crk knockdown mEOC cells （MCAS） was manifested by increased number of enlarged cells filled with vacuoles-like mucus observed by phase-contrast microscope and cytoplasmic PAS staining; and enhanced mucus secretion was represented by the assembly of pericellular matrix in particle excluding assay and increased mucus area in tumor lumps from nude mice models. Conclusion： The course of carcinogenesis in mEOC is associated with the altered pattern of mucus production and secretion. The adaptor protein Crk is implicated in both pathways.展开更多
Glioblastoma is the most aggressive and invasive brain tumor and has a poor prognosis;elucidating the underlying molecular mechanisms is essential to select molecular targeted therapies.Here,we investigated the effect...Glioblastoma is the most aggressive and invasive brain tumor and has a poor prognosis;elucidating the underlying molecular mechanisms is essential to select molecular targeted therapies.Here,we investigated the effect of microRNAs on the marked invasiveness of glioblastoma.U373 glioblastoma cells were infected with 140 different microRNAs from an OncomiR library,and the effects of the invasion-related microRNAs and targeted molecules were investigated after repeated Matrigel invasion assays.Screening of the OncomiR library identified miR-23a as a key regulator of glioblastoma invasion.In six glioblastoma cell lines,a positive correlation was detected between the expression levels of miR-23a and invasiveness.A luciferase reporter assay demonstrated that homeobox D10(HOXD10)was a miR-23a-target molecule,which was verified by high scores from both the PicTar and miRanda algorithms.Forced expression of miR-23a induced expression of invasion-related molecules,including uPAR,RhoA,and RhoC,and altered expression of glial-mesenchymal transition markers such as Snail,Slug,MMP2,MMP9,MMP14,and E-cadherin;however,these changes in expression levels were reversed by HOXD10 overexpression.Thus,miR-23a significantly promoted invasion of glioblastoma cells with polarized formation of focal adhesions,while exogenous HOXD10 overexpression reversed these phenomena.Here,we identify miR-23a-regulated HOXD10 as a pivotal regulator of invasion in glioblastoma,providing a novel mechanism for the aggressive invasiveness of this tumor and providing insight into potential therapeutic targets.展开更多
文摘BACKGROUND Helicobacter pylori(H.pylori)eradication treatment for primary gastric mucosaassociated lymphoid tissue(MALT)lymphoma has already been established.However,t(11;18)(q21;q21)/API2-MALT1 translocation-positive lesions are a type of primary gastric MALT lymphoma in which a response to eradication treatment is difficult to achieve.In addition,trisomy 18 may be associated with diffuse large B-cell lymphoma(DLBCL)transformation of gastric MALT lymphoma.CASE SUMMARY A 66-year-old man was diagnosed with MALT lymphoma in the ascending colon by colonoscopy and biopsy.Two years later,esophagogastroduodenoscopy revealed chronic atrophic gastritis that was positive for H.pylori,and eradication treatment was administered.Two years and nine months later(at the age of 70),a new ulcerative lesion suggestive of MALT lymphoma appeared in the gastric body,and six months later,a similar lesion was also found in the fundus.One year later(4 years and 3 months after H.pylori eradication),at the age of 72,the lesion in the gastric body had become deeper and had propagated.A biopsy revealed a pathological diagnosis of DLBCL.Both MALT lymphoma lesions in the ascending colon and DLBCL lesions in the stomach were positive for the t(11;18)(q21;q21)/API2-MALT1 translocation,and trisomy 18q21 was also detected.After 6 courses of R-CHOP(rituximab,cyclophosphamide,doxorubicin,vincristine and prednisone)chemotherapy,all of the above lesions disappeared[complete remission(CR)],and CR has been maintained for more than 3 years.In addition,both the colonic and gastric lesions were proven to have the same clonality.CONCLUSION Because the patient had a MALT1 translocation with trisomy 18q21,it was thought that this gastric MALT lymphoma developed independently of H.pylori infection and progressed.
基金Acknowledgments We thank M Hamaguchi （Nagoya Univ., Japan） and T Iwahara （Osaka Bioscience Institute, Japan） forJak null MEFs, and N Gotoh （Tokyo Univ., Japan）, H Higashi （Hokkaido Univ., Japan）, N Mochizuki （National Cardiovascular Cent. Res. Inst., Japan）, H Hanafusa （Prof. emeritus, The Rockefeller Univ., USA and Direc- tor em., OBI, Japan）, SK Hanks （Vanderbilt Univ., USA）, and M Matsuda （Kyoto Univ., Japan） for plasmids. We also thank K Sasai （Hokkaido Univ., Japan） and Y Ohba （Hokkaido Univ., Japan） for valuable discussion. This work was supported in part by grants-in- aid from the Ministry of Education, Science, Culture, and Sports, and the Ministry of Health, Labor, and Welfare, Japan, as well as Suhara Memorial Foundation （Sapporo, Japan）, and the Mochida Medical Science Foundation （Tokyo, Japan）. The work of SF and TK is supported by grants from Cancer Research UK and the Brit- ish Cancer Charity ＂Heads Up＂. We dedicate this work to our great mentor Hidesaburo Hana- fusa, professor emeritus of the Rockefeller University, who passed away on March 15, 2009 at the age of 79. He devoted his life to science and in particular to creating the oncogene research field, to teaching and to providing profound affection to his students and postdocs. All of the alumni of Saburo＇s laboratory pride them- selves in having been his apprentices and we would like to hereby express our deeply felt gratitude to Saburo.
文摘Upon growth factor stimulation, the scaffold protein, Gabl, is tyrosine phosphorylated and subsequently the adaptor protein, Crk, transmits signals from Gabl. We have previously shown that Crk overexpression, which is detectable in various human cancers, induces tyrosine phosphorylation of Gabl without extracellular stimuli. In the present study, the underlying mechanisms were further investigated. Mutational analyses of CrkII demonstrated that the SH2 domain, but not the SH3（N） or the regulatory Y221 residue of CrkII, is critical for the induction of Gabl- Y307 phosphorylation. SH2 mutation of CrkII also decreased the interaction with Gabl. In GST pull-down assay, Crk-SH2 bound to wild-type Gahl, whereas Crk-SH3（N） interacted with the Gabl mutant, which lacks the clus- tered tyrosine region （residues 242-410）. Tyrosine phosphorylation of Gabl was induced by all Crk family proteins, but not other SH2-containing signalling adaptors. Src-family kinase inhibitor, PP2, abrogates Crk-induced tyrosine phosphorylations of Gabl. Y307 phosphorylation was undetectable in fibroblasts lacking Src, Yes, and Fyn, even upon overexpression of Crk, whereas cells lacking only Yes and Fyn still contained Gabl with phosphorylated Y307. Furthermore, Crk induced the phosphorylation of Src-Y416; accordingly the interaction between Crk and Csk was increased. The Gabl-Y307F mutant failed to localize near the plasma membrane even upon HGF stimulation and decreased cell migration. Moreover, Gabl-Y307F disturbed the localization of Crk, FAK, and paxillin, which are the typical components of focal adhesions. Taken together, these results indicate that Crk facilitates tyrosine phosphory- lation of Gabl-Y307 through Src, contributing to the organization of focal adhesions and enhanced cell migration, thereby possibly promoting human cancer development.
基金a grant from the National Natural Science Foundation of China(No.C30672432,No.30772330)the Natural Science Foundation of Chongqing City(No.2007BB5319)the Japan-China Sasakawa Medical Fellowship
文摘Objective： The mucus production is an indicator for the histological grade of mucinous epithelial ovarian cancer （mEOC）. In our previous study, Crk expression was targeted in the human ovarian mucinous adenocarcinoma cell line MCAS through RNA interference, resulting in the establishment of Crk knock down cells. These cells exhibited decreased tumorigenic potential both in vitro and in vivo. The purpose of this study was to investigate if there is any change in the capability of forming mucus in these Crk knock down cells. Methods： Cytoplasmic periodic acid Schiff （PAS） staining and particle excluding assay were conducted to assess the mucus formation within and around cells, respectively. Additionally, the amount of mucus formed in tumor lumps from nude mice model was measured following HE and PAS staining. Results： The increased mucus production in Crk knockdown mEOC cells （MCAS） was manifested by increased number of enlarged cells filled with vacuoles-like mucus observed by phase-contrast microscope and cytoplasmic PAS staining; and enhanced mucus secretion was represented by the assembly of pericellular matrix in particle excluding assay and increased mucus area in tumor lumps from nude mice models. Conclusion： The course of carcinogenesis in mEOC is associated with the altered pattern of mucus production and secretion. The adaptor protein Crk is implicated in both pathways.
基金This work was supported,in part,by Grants-in-Aid from the Ministry of Education,Culture,Sports,Science,and TechnologyJapanese Society for the Promotion of Science+1 种基金Ministry of Health,Labor,and Welfare of Japan as well as a grant from the Japanese Science and Technology AgencyIn addition,this research was supported by Global Station for Soft Matter,a project of Global Institution for Collaborative Research and Education at Hokkaido University.Institute for Chemical Reaction Design and Discovery(ICReDD)was established by World Premier International Research Initiative(WPI),MEXT,Japan.
文摘Glioblastoma is the most aggressive and invasive brain tumor and has a poor prognosis;elucidating the underlying molecular mechanisms is essential to select molecular targeted therapies.Here,we investigated the effect of microRNAs on the marked invasiveness of glioblastoma.U373 glioblastoma cells were infected with 140 different microRNAs from an OncomiR library,and the effects of the invasion-related microRNAs and targeted molecules were investigated after repeated Matrigel invasion assays.Screening of the OncomiR library identified miR-23a as a key regulator of glioblastoma invasion.In six glioblastoma cell lines,a positive correlation was detected between the expression levels of miR-23a and invasiveness.A luciferase reporter assay demonstrated that homeobox D10(HOXD10)was a miR-23a-target molecule,which was verified by high scores from both the PicTar and miRanda algorithms.Forced expression of miR-23a induced expression of invasion-related molecules,including uPAR,RhoA,and RhoC,and altered expression of glial-mesenchymal transition markers such as Snail,Slug,MMP2,MMP9,MMP14,and E-cadherin;however,these changes in expression levels were reversed by HOXD10 overexpression.Thus,miR-23a significantly promoted invasion of glioblastoma cells with polarized formation of focal adhesions,while exogenous HOXD10 overexpression reversed these phenomena.Here,we identify miR-23a-regulated HOXD10 as a pivotal regulator of invasion in glioblastoma,providing a novel mechanism for the aggressive invasiveness of this tumor and providing insight into potential therapeutic targets.
