BACKGROUND Less than 0.5%of intravenously injected drugs reach tumors,contributing to side effects.To limit damage to healthy cells,various delivery vectors have been formulated;yet,previously developed vectors suffer...BACKGROUND Less than 0.5%of intravenously injected drugs reach tumors,contributing to side effects.To limit damage to healthy cells,various delivery vectors have been formulated;yet,previously developed vectors suffer from poor penetration into solid tumors.This issue was resolved by the discovery of HN-1 peptide isolated via biopanning a phage-display library.HN-1 targets human head and neck squamous cell carcinoma(HNSCC)(breast,thyroid;potentially lung,cervix,uterine,colon cancer),translocates across the cell membrane,and efficiently infiltrates solid tumors.HN-1 peptide has been conjugated to various anticancer drugs and imaging agents though the identity of its receptor remained enigmatic.AIM To decipher the clues that pointed to retinoblastoma(Rb)-regulated discoidindomain receptor 1 as the putative receptor for HN-1 is described.METHODS HN-1 peptide was synthesized and purified using reverse-phase highperformance liquid chromatography and gel electrophoresis.The predicted mass was confirmed by mass spectroscopy.To image the 3-dimensional structure of HN-1 peptide,PyMOL was used.Molecular modeling was also performed with PEP-FOLD3 software via RPBS bioinformatics web portal(INSERM,France).The immunohistochemistry results of discoidin domain receptor 1(DDR1)protein were obtained from the publicly accessible database in the Human Protein Atlas portal,which contained the images of immunohistochemically labeled human cancers and the corresponding normal tissues.RESULTS The clues that led to DDR1 involved in metastasis as the putative receptor mediating HN-1 endocytosis are the following:(1)HN-1 is internalized in phosphate-buffered saline and its uptake is competitively inhibited;(2)HN-1(TSPLNIHNGQKL)exhibits similarity with a stretch of amino acids in alpha5 beta3 integrin(KLLITIHDRKEF).Aside from two identical residues(Ile-His)in the middle,the overall distribution of polar and nonpolar residues throughout the sequences is nearly identical.As HN-1 sequence lacks the Arg-Gly-Asp motif recognized by integrins,HN-1 may interact with an"integrin-like"molecule.The tertiary structure of both peptides showed similarity at the 3-dimensional level;(3)HN-1 is internalized by attached cells but not by suspended cells.As culture plates are typically coated with collagen,collagen-binding receptor(expressed by adherent but not suspended cells)may represent the receptor for HN-1;(4)DDR1 is highly expressed in head and neck cancer(or breast cancer)targeted by HN-1;(5)Upon activation by collagen,DDR1 becomes internalized and compartmentalized in endosomes consistent with the determination of’energy-dependent clathrin-mediated endocytosis’as the HN-1 entry route and the identification of HN-1 entrapped vesicles as endosomes;and(6)DDR1 is essential for the development of mammary glands consistent with the common embryonic lineage rationale used to identify breast cancer as an additional target of HN-1.In summary,collagenactivated tyrosine kinase receptor DDR1 overexpressed in HNSCC assumes a critical role in metastasis.Further studies are warranted to assess HN-1 peptide’s interaction with DDR1 and the therapeutic potential of treating metastatic cancer.Additionally,advances in delivery(conformation,endocytic mechanism,repertoire of targeted cancers of HN-1 peptide),tracking(HN-1 conjugated imaging agents),and activity(HN-1 conjugated therapeutic agents)are described.CONCLUSION The discovery of DDR1 as HN-1 peptide’s putative receptor represents a significant advance as it enables identification of metastatic cancers or clinical application of previously developed therapeutics to block metastasis.展开更多
BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(X...BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(XIST)expression has been reported to be elevated in the serum of DN patients.AIM To evaluate the mechanism of lncRNA XIST in renal tubular epithelial cell(RTEC)pyroptosis in DN.METHODS A DN rat model was established through streptozotocin injection,and XIST was knocked down by tail vein injection of the lentivirus LV sh-XIST.Renal metabolic and biochemical indices were detected,and pathological changes in the renal tissue were assessed.The expression of indicators related to inflammation and pyroptosis was also detected.High glucose(HG)was used to treat HK2 cells,and cell viability and lactate dehydrogenase(LDH)activity were detected after silencing XIST.The subcellular localization and downstream mechanism of XIST were investigated.Finally,a rescue experiment was carried out to verify that XIST regulates NLR family pyrin domain containing 3(NLRP3)/caspase-1-mediated RTEC pyroptosis through the microRNA-15-5p(miR-15b-5p)/Toll-like receptor 4(TLR4)axis.RESULTS XIST was highly expressed in the DN models.XIST silencing improved renal metabolism and biochemical indices and mitigated renal injury.The expression of inflammation and pyroptosis indicators was significantly increased in DN rats and HG-treated HK2 cells;cell viability was decreased and LDH activity was increased after HGtreatment. Silencing XIST inhibited RTEC pyroptosis by inhibiting NLRP3/caspase-1. Mechanistically,XIST sponged miR-15b-5p to regulate TLR4. Silencing XIST inhibited TLR4 by promotingmiR-15b-5p. miR-15b-5p inhibition or TLR4 overexpression averted the inhibitory effect ofsilencing XIST on HG-induced RTEC pyroptosis.CONCLUSIONSilencing XIST inhibits TLR4 by upregulating miR-15b-5p and ultimately inhibits renal injury inDN by inhibiting NLRP3/caspase-1-mediated RTEC pyroptosis.展开更多
文摘BACKGROUND Less than 0.5%of intravenously injected drugs reach tumors,contributing to side effects.To limit damage to healthy cells,various delivery vectors have been formulated;yet,previously developed vectors suffer from poor penetration into solid tumors.This issue was resolved by the discovery of HN-1 peptide isolated via biopanning a phage-display library.HN-1 targets human head and neck squamous cell carcinoma(HNSCC)(breast,thyroid;potentially lung,cervix,uterine,colon cancer),translocates across the cell membrane,and efficiently infiltrates solid tumors.HN-1 peptide has been conjugated to various anticancer drugs and imaging agents though the identity of its receptor remained enigmatic.AIM To decipher the clues that pointed to retinoblastoma(Rb)-regulated discoidindomain receptor 1 as the putative receptor for HN-1 is described.METHODS HN-1 peptide was synthesized and purified using reverse-phase highperformance liquid chromatography and gel electrophoresis.The predicted mass was confirmed by mass spectroscopy.To image the 3-dimensional structure of HN-1 peptide,PyMOL was used.Molecular modeling was also performed with PEP-FOLD3 software via RPBS bioinformatics web portal(INSERM,France).The immunohistochemistry results of discoidin domain receptor 1(DDR1)protein were obtained from the publicly accessible database in the Human Protein Atlas portal,which contained the images of immunohistochemically labeled human cancers and the corresponding normal tissues.RESULTS The clues that led to DDR1 involved in metastasis as the putative receptor mediating HN-1 endocytosis are the following:(1)HN-1 is internalized in phosphate-buffered saline and its uptake is competitively inhibited;(2)HN-1(TSPLNIHNGQKL)exhibits similarity with a stretch of amino acids in alpha5 beta3 integrin(KLLITIHDRKEF).Aside from two identical residues(Ile-His)in the middle,the overall distribution of polar and nonpolar residues throughout the sequences is nearly identical.As HN-1 sequence lacks the Arg-Gly-Asp motif recognized by integrins,HN-1 may interact with an"integrin-like"molecule.The tertiary structure of both peptides showed similarity at the 3-dimensional level;(3)HN-1 is internalized by attached cells but not by suspended cells.As culture plates are typically coated with collagen,collagen-binding receptor(expressed by adherent but not suspended cells)may represent the receptor for HN-1;(4)DDR1 is highly expressed in head and neck cancer(or breast cancer)targeted by HN-1;(5)Upon activation by collagen,DDR1 becomes internalized and compartmentalized in endosomes consistent with the determination of’energy-dependent clathrin-mediated endocytosis’as the HN-1 entry route and the identification of HN-1 entrapped vesicles as endosomes;and(6)DDR1 is essential for the development of mammary glands consistent with the common embryonic lineage rationale used to identify breast cancer as an additional target of HN-1.In summary,collagenactivated tyrosine kinase receptor DDR1 overexpressed in HNSCC assumes a critical role in metastasis.Further studies are warranted to assess HN-1 peptide’s interaction with DDR1 and the therapeutic potential of treating metastatic cancer.Additionally,advances in delivery(conformation,endocytic mechanism,repertoire of targeted cancers of HN-1 peptide),tracking(HN-1 conjugated imaging agents),and activity(HN-1 conjugated therapeutic agents)are described.CONCLUSION The discovery of DDR1 as HN-1 peptide’s putative receptor represents a significant advance as it enables identification of metastatic cancers or clinical application of previously developed therapeutics to block metastasis.
基金Supported by Natural Science Foundation of Shenzhen University General Hospital (SUGH2020QD011)
文摘BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(XIST)expression has been reported to be elevated in the serum of DN patients.AIM To evaluate the mechanism of lncRNA XIST in renal tubular epithelial cell(RTEC)pyroptosis in DN.METHODS A DN rat model was established through streptozotocin injection,and XIST was knocked down by tail vein injection of the lentivirus LV sh-XIST.Renal metabolic and biochemical indices were detected,and pathological changes in the renal tissue were assessed.The expression of indicators related to inflammation and pyroptosis was also detected.High glucose(HG)was used to treat HK2 cells,and cell viability and lactate dehydrogenase(LDH)activity were detected after silencing XIST.The subcellular localization and downstream mechanism of XIST were investigated.Finally,a rescue experiment was carried out to verify that XIST regulates NLR family pyrin domain containing 3(NLRP3)/caspase-1-mediated RTEC pyroptosis through the microRNA-15-5p(miR-15b-5p)/Toll-like receptor 4(TLR4)axis.RESULTS XIST was highly expressed in the DN models.XIST silencing improved renal metabolism and biochemical indices and mitigated renal injury.The expression of inflammation and pyroptosis indicators was significantly increased in DN rats and HG-treated HK2 cells;cell viability was decreased and LDH activity was increased after HGtreatment. Silencing XIST inhibited RTEC pyroptosis by inhibiting NLRP3/caspase-1. Mechanistically,XIST sponged miR-15b-5p to regulate TLR4. Silencing XIST inhibited TLR4 by promotingmiR-15b-5p. miR-15b-5p inhibition or TLR4 overexpression averted the inhibitory effect ofsilencing XIST on HG-induced RTEC pyroptosis.CONCLUSIONSilencing XIST inhibits TLR4 by upregulating miR-15b-5p and ultimately inhibits renal injury inDN by inhibiting NLRP3/caspase-1-mediated RTEC pyroptosis.
