AIM: To evaluate ATP-binding cassette(ABC) transporters in colonic pathophysiology as they had recently been related to colorectal cancer(CRC) development. METHODS: Literature search was conducted on Pub Med using com...AIM: To evaluate ATP-binding cassette(ABC) transporters in colonic pathophysiology as they had recently been related to colorectal cancer(CRC) development. METHODS: Literature search was conducted on Pub Med using combinations of the following terms: ABC transporters, ATP binding cassette transporter proteins, inflammatory bowel disease, ulcerative, colitis, Crohns disease, colorectal cancer, colitis, intestinal inflammation, intestinal carcinogenesis, ABCB1/P-glycoprotein(P-gp/CD243/MDR1), ABCC2/multidrug resistance protein 2(MRP2) and ABCG2/breast cancer resistance protein(BCRP), Abcb1/Mdr1 a, abcc2/Mrp2, abcg2/Bcrp, knock-out mice, tight junction, membrane lipid function. RESULTS: Recently, human studies reported thatchanges in the levels of ABC transporters were early events in the adenoma-carcinoma sequence leading to CRC. A link between ABCB1, high fat diet and gut microbes in relation to colitis was suggested by the animal studies. The finding that colitis was preceded by altered gut bacterial composition suggests that deletion of Abcb1 leads to fundamental changes of hostmicrobiota interaction. Also, high fat diet increases the frequency and severity of colitis in specific pathogenfree Abcb1 KO mice. The Abcb1 KO mice might thus serve as a model in which diet/environmental factors and microbes may be controlled and investigated in relation to intestinal inflammation. Potential molecular mechanisms include defective transport of inflammatory mediators and/or phospholipid translocation from one side to the other of the cell membrane lipid bilayer by ABC transporters affecting inflammatory response and/or function of tight junctions, phagocytosis and vesicle trafficking. Also, diet and microbes give rise to molecules which are potential substrates for the ABC transporters and which may additionally affect ABC transporter function through nuclear receptors and transcriptional regulation. Another critical role of ABCB1 was suggested by the finding that ABCB1 expression identifies a subpopulation of pro-inflammatory Th17 cells which were resistant to treatment with glucocorticoids. The evidence for the involvement of ABCC2 and ABCG2 in colonic pathophysiology was weak. CONCLUSION: ABCB1, diet, and gut microbes mutually interact in colonic inflammation, a well-known risk factor for CRC. Further insight may be translated into preventive and treatment strategies.展开更多
Dear Editor,Despite the improved outcome of advanced estrogen receptor-positive(ER+)breast cancer patients treated with endocrine therapy in combination with either a cyclindependent kinase 4/6 inhibitor(CDK4/6i)or a ...Dear Editor,Despite the improved outcome of advanced estrogen receptor-positive(ER+)breast cancer patients treated with endocrine therapy in combination with either a cyclindependent kinase 4/6 inhibitor(CDK4/6i)or a phosphoinositide 3-kinase inhibitor(PI3Ki),the disease will eventually progress,and the optimal treatment strategy upon progression remains undefined[1-4].To address this,we developed MCF-7-and T47D-derived PIK3CAmutated breast cancer cell lines[5]resistant to combined CDK4/6i palbociclib and fulvestrant(MPF-R and TPFR)or combined PI3Ki alpelisib and fulvestrant(MAF-R and TAF-R),respectively(Supplementary Materials and Methods).Drug-sensitive isogenic cells(M-S and T-S)grown in parallel with MPF-R and TPF-R cells and the original MCF-7/S0.5 and T47D cells were analyzed for comparison.展开更多
文摘AIM: To evaluate ATP-binding cassette(ABC) transporters in colonic pathophysiology as they had recently been related to colorectal cancer(CRC) development. METHODS: Literature search was conducted on Pub Med using combinations of the following terms: ABC transporters, ATP binding cassette transporter proteins, inflammatory bowel disease, ulcerative, colitis, Crohns disease, colorectal cancer, colitis, intestinal inflammation, intestinal carcinogenesis, ABCB1/P-glycoprotein(P-gp/CD243/MDR1), ABCC2/multidrug resistance protein 2(MRP2) and ABCG2/breast cancer resistance protein(BCRP), Abcb1/Mdr1 a, abcc2/Mrp2, abcg2/Bcrp, knock-out mice, tight junction, membrane lipid function. RESULTS: Recently, human studies reported thatchanges in the levels of ABC transporters were early events in the adenoma-carcinoma sequence leading to CRC. A link between ABCB1, high fat diet and gut microbes in relation to colitis was suggested by the animal studies. The finding that colitis was preceded by altered gut bacterial composition suggests that deletion of Abcb1 leads to fundamental changes of hostmicrobiota interaction. Also, high fat diet increases the frequency and severity of colitis in specific pathogenfree Abcb1 KO mice. The Abcb1 KO mice might thus serve as a model in which diet/environmental factors and microbes may be controlled and investigated in relation to intestinal inflammation. Potential molecular mechanisms include defective transport of inflammatory mediators and/or phospholipid translocation from one side to the other of the cell membrane lipid bilayer by ABC transporters affecting inflammatory response and/or function of tight junctions, phagocytosis and vesicle trafficking. Also, diet and microbes give rise to molecules which are potential substrates for the ABC transporters and which may additionally affect ABC transporter function through nuclear receptors and transcriptional regulation. Another critical role of ABCB1 was suggested by the finding that ABCB1 expression identifies a subpopulation of pro-inflammatory Th17 cells which were resistant to treatment with glucocorticoids. The evidence for the involvement of ABCC2 and ABCG2 in colonic pathophysiology was weak. CONCLUSION: ABCB1, diet, and gut microbes mutually interact in colonic inflammation, a well-known risk factor for CRC. Further insight may be translated into preventive and treatment strategies.
基金funded in part by grants from the Danish Cancer Society(to Henrik J.Ditzel)Health Insurance“Denmark”(to Henrik J.Ditzel)+1 种基金Academy of Geriatric Cancer Research(AgeCare)(to Henrik J.Ditzel)Pink Tribute(to Henrik J.Ditzel).
文摘Dear Editor,Despite the improved outcome of advanced estrogen receptor-positive(ER+)breast cancer patients treated with endocrine therapy in combination with either a cyclindependent kinase 4/6 inhibitor(CDK4/6i)or a phosphoinositide 3-kinase inhibitor(PI3Ki),the disease will eventually progress,and the optimal treatment strategy upon progression remains undefined[1-4].To address this,we developed MCF-7-and T47D-derived PIK3CAmutated breast cancer cell lines[5]resistant to combined CDK4/6i palbociclib and fulvestrant(MPF-R and TPFR)or combined PI3Ki alpelisib and fulvestrant(MAF-R and TAF-R),respectively(Supplementary Materials and Methods).Drug-sensitive isogenic cells(M-S and T-S)grown in parallel with MPF-R and TPF-R cells and the original MCF-7/S0.5 and T47D cells were analyzed for comparison.
