BACKGROUND: Exploring the underlying mechanism of rituximab resistance is critical to improve the outcomes of patients with diffuse large B-cell lymphoma (DLBCL). Here, we tried to identify the effects of the axon guidance factor semaphorin-3F (SEMA3F) on rituximab resistance as well as its therapeutic value in DLBCL. METHODS: The effects of SEMA3F on the treatment response to rituximab were investigated by gain- or loss-of-function experiments. The role of the Hippo pathway in SEMA3F-mediated activity was explored. A xenograft mouse model generated by SEMA3F knockdown in cells was used to evaluate rituximab sensitivity and combined therapeutic effects. The prognostic value of SEMA3F and TAZ (WW domain-containing transcription regulator protein 1) was examined in the Gene Expression Omnibus (GEO) database and human DLBCL specimens. RESULTS: We found that loss of SEMA3F was related to a poor prognosis in patients who received rituximab-based immunochemotherapy instead of chemotherapy regimen. Knockdown of SEMA3F significantly repressed the expression of CD20 and reduced the proapoptotic activity and complement-dependent cytotoxicity (CDC) activity induced by rituximab. We further demonstrated that the Hippo pathway was involved in the SEMA3F-mediated regulation of CD20. Knockdown of SEMA3F expression induced the nuclear accumulation of TAZ and inhibited CD20 transcriptional levels via direct binding of the transcription factor TEAD2 and the CD20 promoter. Moreover, in patients with DLBCL, SEMA3F expression was negatively correlated with TAZ, and patients with SEMA3F low TAZ high had a limited benefit from a rituximab-based strategy. Specifically, treatment of DLBCL cells with rituximab and a YAP/TAZ inhibitor showed promising therapeutic effects in vitro and in vivo . CONCLUSION Our study thus defined a previously unknown mechanism of SEMA3F-mediated rituximab resistance through TAZ activation in DLBCL and identified potential therapeutic targets in patients.
Humans ; Animals ; Mice ; Rituximab/therapeutic use* ; Hippo Signaling Pathway ; Lymphoma, Large B-Cell, Diffuse/pathology* ; Prognosis ; Semaphorins/therapeutic use* ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Membrane Proteins/genetics* ; Nerve Tissue Proteins/genetics*

Objective: To investigate the expression of glycoprotein non metastatic melanoma protein B (GPNMB) in renal eosinophilic tumors and to compare the value of GPNMB with CK20, CK7 and CD117 in the differential diagnosis of renal eosinophilic tumors. Methods: Traditional renal tumor eosinophil subtypes, including 22 cases of renal clear cell carcinoma eosinophil subtype (e-ccRCC), 19 cases of renal papillary cell carcinoma eosinophil subtype (e-papRCC), 17 cases of renal chromophobe cell carcinoma eosinophil subtype (e-chRCC), 12 cases of renal oncocytoma (RO) and emerging renal tumor types with eosinophil characteristics [3 cases of eosinophilic solid cystic renal cell carcinoma (ESC RCC), 3 cases of renal low-grade eosinophil tumor (LOT), 4 cases of fumarate hydratase-deficient renal cell carcinoma (FH-dRCC) and 5 cases of renal epithelioid angiomyolipoma (E-AML)], were collected at the Affiliated Drum Tower Hospital of Nanjing University Medical School from January 2017 to March 2022. The expression of GPNMB, CK20, CK7 and CD117 was detected by immunohistochemistry and statistically analyzed. Results: GPNMB was expressed in all emerging renal tumor types with eosinophil characteristics (ESC RCC, LOT, FH-dRCC) and E-AML, while the expression rates in traditional renal eosinophil subtypes e-papRCC, e-chRCC, e-ccRCC and RO were very low or zero (1/19, 1/17, 0/22 and 0/12, respectively); the expression rate of CK7 in LOT (3/3), e-chRCC (15/17), e-ccRCC (4/22), e-papRCC (2/19), ESC RCC (0/3), RO (4/12), E-AML(1/5), and FH-dRCC (2/4) variedly; the expression of CK20 was different in ESC RCC (3/3), LOT(3/3), e-chRCC(1/17), RO(9/12), e-papRCC(4/19), FH-dRCC(1/4), e-ccRCC(0/22) and E-AML(0/5), and so did that of CD117 in e-ccRCC(2/22), e-papRCC(1/19), e-chRCC(16/17), RO(10/12), ESC RCC(0/3), LOT(1/3), E-AML(2/5) and FH-dRCC(1/4). GPNMB had 100% sensitivity and 97.1% specificity in distinguishing E-AML and emerging renal tumor types (such as ESC RCC, LOT, FH-dRCC) from traditional renal tumor types (such as e-ccRCC, e-papRCC, e-chRCC, RO),respectively. Compared with CK7, CK20 and CD117 antibodies, GPNMB was more effective in the differential diagnosis (P<0.05). Conclusion: As a new renal tumor marker, GPNMB can effectively distinguish E-AML and emerging renal tumor types with eosinophil characteristics such as ESC RCC, LOT, FH-dRCC from traditional renal tumor eosinophil subtypes such as e-ccRCC, e-papRCC, e-chRCC and RO, which is helpful for the differential diagnosis of renal eosinophilic tumors.
Humans ; Kidney Neoplasms/pathology* ; Carcinoma, Renal Cell/pathology* ; Diagnosis, Differential ; Angiomyolipoma/diagnosis* ; Biomarkers, Tumor/metabolism* ; Leukemia, Myeloid, Acute/diagnosis* ; Membrane Glycoproteins

Cancer stem cell-like cells (CSCs) play an integral role in the heterogeneity, metastasis, and treatment resistance of head and neck squamous cell carcinoma (HNSCC) due to their high tumor initiation capacity and plasticity. Here, we identified a candidate gene named LIMP-2 as a novel therapeutic target regulating HNSCC progression and CSC properties. The high expression of LIMP-2 in HNSCC patients suggested a poor prognosis and potential immunotherapy resistance. Functionally, LIMP-2 can facilitate autolysosome formation to promote autophagic flux. LIMP-2 knockdown inhibits autophagic flux and reduces the tumorigenic ability of HNSCC. Further mechanistic studies suggest that enhanced autophagy helps HNSCC maintain stemness and promotes degradation of GSK3β, which in turn facilitates nuclear translocation of β-catenin and transcription of downstream target genes. In conclusion, this study reveals LIMP-2 as a novel prospective therapeutic target for HNSCC and provides evidence for a link between autophagy, CSC, and immunotherapy resistance.
Humans ; Autophagy ; Carcinoma, Squamous Cell/pathology* ; Cell Line, Tumor ; Glycogen Synthase Kinase 3 beta/metabolism* ; Head and Neck Neoplasms/pathology* ; Neoplastic Stem Cells/pathology* ; Squamous Cell Carcinoma of Head and Neck/pathology* ; Lysosome-Associated Membrane Glycoproteins

Platycodon grandiflorum (Jacq.) A. DC. is a famous medicinal plant commonly used in East Asia. Triterpene saponins isolated from P. grandiflorum are the main biologically active compounds, among which polygalacin D (PGD) has been reported to be an anti-tumor agent. However, its anti-tumor mechanism against hepatocellular carcinoma is unknown. This study aimed to explore the inhibitory effect of PGD in hepatocellular carcinoma cells and related mechanisms of action. We found that PGD exerted significant inhibitory effect on hepatocellular carcinoma cells through apoptosis and autophagy. Analysis of the expression of apoptosis-related proteins and autophagy-related proteins revealed that this phenomenon was attributed to the mitochondrial apoptosis and mitophagy pathways. Subsequently, using specific inhibitors, we found that apoptosis and autophagy had mutually reinforcing effects. In addition, further analysis of autophagy showed that PGD induced mitophagy by increasing BCL2 interacting protein 3 like (BNIP3L) levels.In vivo experiments demonstrated that PGD significantly inhibited tumor growth and increased the levels of apoptosis and autophagy in tumors. Overall, our findings showed that PGD induced cell death of hepatocellular carcinoma cells primarily through mitochondrial apoptosis and mitophagy pathways. Therefore, PGD can be used as an apoptosis and autophagy agonist in the research and development of antitumor agents.
Humans ; Mitophagy ; Carcinoma, Hepatocellular/pathology* ; Liver Neoplasms/pathology* ; Cell Line ; Autophagy ; Apoptosis ; Membrane Proteins ; Proto-Oncogene Proteins/genetics* ; Tumor Suppressor Proteins/pharmacology*

The 2019 novel coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has occurred in China and around the world. SARS-CoV-2-infected patients with severe pneumonia rapidly develop acute respiratory distress syndrome (ARDS) and die of multiple organ failure. Despite advances in supportive care approaches, ARDS is still associated with high mortality and morbidity. Mesenchymal stem cell (MSC)-based therapy may be an potential alternative strategy for treating ARDS by targeting the various pathophysiological events of ARDS. By releasing a variety of paracrine factors and extracellular vesicles, MSC can exert anti-inflammatory, anti-apoptotic, anti-microbial, and pro-angiogenic effects, promote bacterial and alveolar fluid clearance, disrupt the pulmonary endothelial and epithelial cell damage, eventually avoiding the lung and distal organ injuries to rescue patients with ARDS. An increasing number of experimental animal studies and early clinical studies verify the safety and efficacy of MSC therapy in ARDS. Since low cell engraftment and survival in lung limit MSC therapeutic potentials, several strategies have been developed to enhance their engraftment in the lung and their intrinsic, therapeutic properties. Here, we provide a comprehensive review of the mechanisms and optimization of MSC therapy in ARDS and highlighted the potentials and possible barriers of MSC therapy for COVID-19 patients with ARDS.
Adoptive Transfer ; Alveolar Epithelial Cells ; pathology ; Animals ; Apoptosis ; Betacoronavirus ; Body Fluids ; metabolism ; CD4-Positive T-Lymphocytes ; immunology ; Clinical Trials as Topic ; Coinfection ; prevention & control ; therapy ; Coronavirus Infections ; complications ; immunology ; Disease Models, Animal ; Endothelial Cells ; pathology ; Extracorporeal Membrane Oxygenation ; Genetic Therapy ; methods ; Genetic Vectors ; administration & dosage ; therapeutic use ; Humans ; Immunity, Innate ; Inflammation Mediators ; metabolism ; Lung ; pathology ; physiopathology ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stem Cells ; physiology ; Multiple Organ Failure ; etiology ; prevention & control ; Pandemics ; Pneumonia, Viral ; complications ; immunology ; Respiratory Distress Syndrome, Adult ; immunology ; pathology ; therapy ; Translational Medical Research

Proteins are the physical basis of life and perform all kinds of life activities. Proteins have different orientations and function in different tissues. The same protein, located in different subcellular regions, can perform different and even opposite functions. Both functional and structural proteins are capable of undergoing re-localization which can directly or indirectly participate in signal transduction. Due to abnormal transduction of signals during carcinogenesis, the proteins originally expressed in the cytoplasm are translocated into the nucleus and lead to functional changes in the tumor tissue. The changes of protein localization are affected by many factors, including the interaction between proteins, expression level of proteins and the cleaved intracellular domain of transmembrane protein.
Carcinogenesis ; pathology ; Cell Line, Tumor ; Cell Nucleus ; metabolism ; Cytoplasm ; metabolism ; Gene Expression Regulation, Neoplastic ; Humans ; Membrane Proteins ; metabolism ; Protein Domains ; Protein Transport ; physiology ; Signal Transduction

OBJECTIVE: To investigate the protective effects of Sestrin2 protein on lung epithelial Beas-2B cells in the heat-exposure environment and its mechanism. METHODS: Lung epithelial Beas-2B cells were cultured at 37℃, 39℃, 40℃ and 41℃ respectively. Cells were harvested at different times (0, 3, 6 and 12 h) after pancreatin digestion. The expressions of Sestrin2, superoxide dismutase(SOD), reactive oxygen species(ROS), cell mitochondrial membrane potential and apoptosis rate of cells were detected by Western blot, fluorescence spectrophotometer and flow cytometry, respectively. Gene expression sequence was cloned into high expression plasmid pcDNA3.1. Beas-2B cells were transfected by Lipfectamine 2000 to construct Sestrin2 and SOD high expression cells. The changes of mitochondrial membrane potential and cell apoptosis were observed in the Sestrin2 and SOD high expression cells. RESULTS: With the increase of temperature, the expression level of Sestrin2 protein in heat treatment group was decreased compared with the control group. When Beas-2B cells were exposed to 41℃, the ROS level was increased, mitochondrial membrane potential was decreased significantly and apoptosis rate was increased at different time points. After high expression of Sestrin2 and SOD in the Beas-2B cells, the expression level of ROS was decreased and the change tendency of mitochondrial membrane potential was decreased, and the apoptosis rate was reduced at 41℃ exposure. CONCLUSION Sestrin2 can alleviate the apoptosis of lung epithelial cells induced by heat exposure through mitochondrial membrane potential and SOD, which has protective effect on lung epithelial Beas-2B cells.
Apoptosis ; Cell Line ; Epithelial Cells ; pathology ; Hot Temperature ; Humans ; Membrane Potential, Mitochondrial ; Nuclear Proteins ; genetics ; metabolism ; Reactive Oxygen Species ; metabolism ; Superoxide Dismutase ; metabolism ; Transfection

Malignancy of the middle ear is rare and its estimated incidence is 0.18 cases per million people in the US, with its most common type being squamous cell carcinoma. Squamous cell carcinoma in situ is thought to be a precursor to squamous cell carcinoma, which is extremely rare in the middle ear. The pathology reports of squamous cell carcinoma have not been well-characterized as it has not been reported to date in Korea. Here, we report a case of squamous cell carcinoma in situ of the middle ear in a 66-year-old man, who presented with otorrhea and tympanic membrane perforation.
Aged ; Carcinoma in Situ ; Carcinoma, Squamous Cell ; Ear, Middle ; Epithelial Cells ; Humans ; Incidence ; Korea ; Pathology ; Tympanic Membrane Perforation

Huntington's disease (HD) is a neurodegenerative disease caused by a polyglutamine expansion in the huntingtin (Htt) protein. Mutant Htt causes synaptic transmission dysfunctions by interfering in the expression of synaptic proteins, leading to early HD symptoms. Synaptic vesicle proteins 2 (SV2s), a family of synaptic vesicle proteins including 3 members, SV2A, SV2B, and SV2C, plays important roles in synaptic physiology. Here, we investigated whether the expression of SV2s is affected by mutant Htt in the brains of HD transgenic (TG) mice and Neuro2a mouse neuroblastoma cells (N2a cells) expressing mutant Htt. Western blot analysis showed that the protein levels of SV2A and SV2B were not significantly changed in the brains of HD TG mice expressing mutant Htt with 82 glutamine repeats. However, in the TG mouse brain there was a dramatic decrease in the protein level of SV2C, which has a restricted distribution pattern in regions particularly vulnerable in HD. Immunostaining revealed that the immunoreactivity of SV2C was progressively weakened in the basal ganglia and hippocampus of TG mice. RT-PCR demonstrated that the mRNA level of SV2C progressively declined in the TG mouse brain without detectable changes in the mRNA levels of SV2A and SV2B, indicating that mutant Htt selectively inhibits the transcriptional expression of SV2C. Furthermore, we found that only SV2C expression was progressively inhibited in N2a cells expressing a mutant Htt containing 120 glutamine repeats. These findings suggest that the synaptic dysfunction in HD results from the mutant Htt-mediated inhibition of SV2C transcriptional expression. These data also imply that the restricted distribution and decreased expression of SV2C contribute to the brain region-selective pathology of HD.
Aging ; metabolism ; Animals ; Brain ; metabolism ; pathology ; Cell Line, Tumor ; Gene Expression ; physiology ; Huntingtin Protein ; genetics ; metabolism ; Membrane Glycoproteins ; metabolism ; Mice ; Mice, Transgenic ; Mutation ; Nerve Tissue Proteins ; metabolism ; RNA, Messenger ; metabolism ; Transcription, Genetic ; physiology

Our previous studies proposed that Alzheimer's disease (AD) is a metabolic disorder and hypothesized that abnormal brain glucose metabolism inducing multiple pathophysiological cascades contributes to AD pathogenesis. Aging is one of the great significant risk factors for AD. Membrane aging is first prone to affect the function and structure of the brain by impairing glucose metabolism. We presume that risk factors of AD, including genetic factors (e.g., the apolipoprotein E ε4 allele and genetic mutations) and non-genetic factors (such as fat, diabetes, and cardiac failure) accelerate biomembrane aging and lead to the onset and development of the disease. In this review, we further modify our previous hypothesis to demonstrate "membrane aging" as an initial pathogenic factor that results in functional and structural alterations of membranes and, consequently, glucose hypometabolism and multiple pathophysiological cascades.
Aging ; pathology ; Alzheimer Disease ; etiology ; pathology ; Animals ; Brain ; pathology ; Cell Membrane ; pathology ; Humans