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Objective To detect the expression of lysosome-associated membrane protein 1(LAMP1) in colorectal cancer (CRC) and study the relationship between LAMP1 expression and important clinical and pathological indicators of CRC, especially disease prognosis. Methods The expression and prognostic characteristics of LAMP1 in CRC were retrieved through bioinformatics analysis at the big data level. qPCR and immunohistochemical (IHC) detection were performed on 10 clinical CRC tumor tissues and tissue chips containing 60 CRC samples. Univariate and multivariate Cox regression and Kaplan-Meier survival analysis were used to analyze the prognostic factors of CRC. Results Big data showed that LAMP1 protein was mainly located in lysosomes and had varying degrees of high expression in CRC cell lines, and was significantly higher in CRC tumor tissues than in normal control tissues. The recurrence free survival (RFS) and overall survival (OS) of CRC patients with high LAMP1 expression were lower than those with low LAMP1 expression. Both qPCR and IHC results of 10 clinical cases showed that the expression of LAMP1 in CRC was significantly higher than that in adjacent control tissues (P＜0.05). In the analysis of 60 cases of cohort, univariate Cox model analysis showed that LAMP1 expression (P=0.030), tumor differentiation (P=0.041), CEA level (P=0.028) and distant metastasis (P=0.002) were significantly correlated with the prognosis of CRC. Multivariate analysis showed that tumor differentiation (P=0.006) and distant metastasis (P=0.041) were independent prognostic factors; Survival analysis showed that the overall survival was shorter in patients with high expression of LAMP1, poor tumor differentiation, CEA level≥15 ng/mL and positive distant metastasis. Conclusion LAMP1 is abnormal highly expressed in CRC. LAMP1 expression is significantly correlated with CRC malignant phenotype, which may serve as a predictive indicator of CRC prognosis.

Vγ9Vδ2 T cells are attractive effector cells for immunotherapy with potent cytotoxic activity against a variety of malignant cells. However, the effect of Vγ9Vδ2 T cells on chemotherapy‐resistant acute myeloid leukemia (AML) blasts, especially highly refractory leukemia stem cells (LSCs) is still unknown. In this study, we investigated the effect of cytotoxicity of allogeneic Vγ9Vδ2 T cells on chemotherapy‐resistant AML cell lines, as well as on primary AML blasts and LSCs obtained from refractory AML patients. The results indicated that Vγ9Vδ2 T cells can efficiently kill drug‐resistant AML cell lines in vitro and in vivo, and the sensitivity of AML cells to Vγ9Vδ2 T cell–mediated cytotoxicity is not influenced by the sensitivity of AML cells to chemotherapy. We further found that Vγ9Vδ2 T cells exhibited a comparable effect of cytotoxicity against LSCs to primary AML blasts. More importantly, we revealed that the CD226–extracellular signal–regulatory kinase1/2 (ERK1/2)–lysosome‐associated membrane protein 1 (LAMP1) pathway is an important mechanism for Vγ9Vδ2 T cell–induced cytotoxicity against AML cells. First, Vγ9Vδ2 T cells recognized AML cells by receptor‐ligand interaction of CD226–Nectin‐2, which then induced ERK1/2 phosphorylation in Vγ9Vδ2 T cells. Finally, triggering the movement of lytic granules toward AML cells induced cytolysis of AML cells. The expression level of Nectin‐2 may be used as a novel marker to predict the susceptibility/resistance of AML cells to Vγ9Vδ2 T cell treatment. [ABSTRACT FROM AUTHOR]

• LAMP1 accumulates at amyloid beta plaques in AppNL-G-F/NL-G-F (knock-in) mouse brain. • Lysosomal hydrolases are enriched at amyloid beta plaques in AppNL-G-F/NL-G-F mice. • Some lysosomal network proteins are elevated in AppNL-G-F/NL-G-F cortex. • Lysosomal network dysfunction in AppNL-G-F/NL-G-F mice resembles human AD. Lysosomal network dysfunction is a prominent feature of Alzheimer's disease (AD). Although transgenic mouse models of AD are known to model some aspects of lysosomal network dysfunction, the lysosomal network has not yet been examined in the knock-in AppNL-G-F/NL-G-F mouse. We aimed to determine whether AppNL-G-F/NL-G-F mice exhibit disruptions to the lysosomal network in the brain. Lysosome-associated membrane protein 1 (LAMP1) and cathepsins B, L and D accumulated at amyloid beta plaques in the AppNL-G-F/NL-G-F mice, as occurs in human Alzheimer's patients. The accumulation of these lysosomal proteins occurred early in the development of neuropathology, presenting at the earliest and smallest amyloid beta plaques observed. AppNL-G-F/NL-G-F mice also exhibited elevated activity of β-hexosaminidase and cathepsins D/E and elevated levels of selected lysosomal network proteins, namely LAMP1, cathepsin D and microtubule-associated protein light chain 3 (LC3-II) in the cerebral cortex, as determined by western blot. Elevation of cathepsin D did not change the extent of co-localisation between cathepsin D and LAMP1 in the AppNL-G-F/NL-G-F mice. These findings demonstrate that perturbations of the lysosomal network occur in the AppNL-G-F/NL-G-F mouse model, further validating its use an animal model of pre-symptomatic AD. [ABSTRACT FROM AUTHOR]

Progranulin (PGRN) is known to play a role in the pathogenesis of neurodegenerative diseases. Recently, it has been demonstrated that patients with the homozygous mutation in the GRN gene present with neuronal ceroid lipofuscinosis, and there is growing evidence that PGRN is related to lysosomal function. In the present study, we investigated the possible role of PGRN in the lysosomes of activated microglia in the cerebral cortex after traumatic brain injury (TBI). We showed that the mouse GRN gene has two possible coordinated lysosomal expression and regulation (CLEAR) sequences that bind to transcription factor EB (TFEB), a master regulator of lysosomal genes. PGRN was colocalized with Lamp1, a lysosomal marker, and Lamp1-positive areas in GRN-deficient (KO) mice were significantly expanded compared with wild-type (WT) mice after TBI. Expression of all the lysosome-related genes examined in KO mice was significantly higher than that in WT mice. The number of activated microglia with TFEB localized to the nucleus was also significantly increased in KO as compared with WT mice. Since the TFEB translocation is regulated by the mammalian target of rapamycin complex 1 (mTORC1) activity in the lysosome, we compared ribosomal S6 kinase 1 (S6K1) phosphorylation that reflects mTORC1 activity. S6K1 phosphorylation in KO mice was significantly lower than that in WT mice. In addition, the number of nissl-positive and fluoro-jade B-positive cells around the injury was significantly decreased and increased, respectively, in KO as compared with WT mice. These results suggest that PGRN localized in the lysosome is involved in the activation of mTORC1, and its deficiency leads to increased TFEB nuclear translocation with a resultant increase in lysosomal biogenesis in activated microglia and exacerbated neuronal damage in the cerebral cortex after TBI., (Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.)

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown etiology and abnormality of hepatobiliary transport might contribute to its pathogenesis. In this study, we aimed to isolate and identify new molecules associated with PBC. With hepatocyte canalicular membrane vesicles (CMVs) of PBC patients as immunogens, we screened the monoclonal antibody 1F9 (mAb1F9), whose antigen dominantly recognized the subapical domains in hepatocytes in normal livers. Immunohistochemistry revealed that the expression of mAb1F9 antigen (mAb1F9-Ag) significantly increased in PBC livers compared with control groups including normal livers, cirrhosis or cholestasis other than PBC. Interestingly, the augmented expression of mAb1F9-Ag was correlated with the severity of PBC, and ursodeoxycholic acid treatment may significantly improve the recovery of mAb1F9-Ag. In addition, redistribution of mAb1F9-Ag was found in 46% of PBC. mAb1F9-Ag was isolated and analyzed with mass spectrometry, which indicated lysosome-associated membrane protein 2 (LAMP-2) as the candidate. Further studies showed that mAb1F9 recognized LAMP-2 immunoprecipitates and vice verse, mAb1F9 reacted with recombinant LAMP-2. mAb1F9 and LAMP-2 antibody exhibited similar staining pattern and displayed similar subcellular localization. Together, the identity of mAb1F9-Ag is LAMP-2, suggesting that LAMP-2 may assist in the differentiation of PBC and predict a poor outcome in patients with PBC., Biological Significance: This manuscript describes the expression of a specific antibody, named mAb1F9. The antigen recognized by mAb1F9 may assist in the differentiation of primary biliary cirrhosis (PBC) and predict a poor outcome in patients with PBC. Through antigen identification, we confirm the identity of mAb1F9-Ag as lysosome-associated membrane protein 2 (LAMP-2). The clinical relevance of the manuscript is well regarded since markers are rare and usually not successful for PBC diagnosis and treatment., (© 2013.)