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1.
Small ; 19(11): e2204747, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36585358

RESUMO

As the foremost cause of cancer-related death, metastasis consists of three steps: invasion, circulation, and colonization. Only targeting one single phase of the metastasis cascade may be insufficient since there are many alternative routes for tumor cells to disseminate. Here, to target the whole cascade of metastasis, hybrid erythrocyte and tumor cell membrane-coated nanoparticle (Hyb-NP) is designed with dual functions of increasing circulation time and recognizing primary, circulating, and colonized tumors. After loading with monensin, a recently reported metastasis inhibitor, the delivery system profoundly reduces spontaneous metastasis in an orthotopic breast cancer model. Underlying mechanism studies reveal that Hyb-NP can deliver monensin to its action site in the Golgi apparatus, and in return, monensin can block the exocytosis of Hyb-NP from the Golgi apparatus, forming a reservoir-like subcellular structure. Notably, the Golgi apparatus reservoir displays three vital functions for suppressing metastasis initialization, including enhanced subcellular drug retention, metastasis-related cytokine release inhibition, and directional migration inhibition. Collectively, based on metastasis cascade targeting at the tissue level, further formation of the Golgi apparatus drug reservoir at the subcellular level provides a potential therapeutic strategy for cancer metastasis suppression.


Assuntos
Monensin , Neoplasias , Humanos , Monensin/farmacologia , Complexo de Golgi/ultraestrutura , Citoplasma
2.
Small ; 18(6): e2104591, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34859582

RESUMO

The endoplasmic reticulum (ER) in cancer cells has been considered as a pharmacological target. Still, the effects of a ER-targeted system remain less investigated, due to the fact that most chemo-drugs take actions in the nucleus. Here, it is demonstrated that ER-targeted delivery of doxorubicin (DOX), a typically nucleus-tropic-and-acting agent, attenuates its original effect on cytotoxicity while generating new functions favorable for immune activation. First, a library of DOX derivatives with variable ER-targeting abilities is synthesized. The results reveal that higher ER-targeting efficiency correlates with greater ER stress. As compared with naïve drug, ER-targeted DOX considerably alters the mode of action from nuclear DNA damage-associated cytotoxicity to ER stress-mediated calreticulin exposure. Consequently, ER-targeted DOX decreases cytotoxicity but increases the capability to induce immunogenic cell death (ICD). Therefore, a platform combining naïve and ER-targeted DOX is constructed for in vivo application. Conventional polymer-DOX conjugate inhibits tumor growth by exerting a direct killing effect, and ER-targeted polymer-DOX conjugate suppresses residual tumors by eliciting ICD-associated immunity, together resulting in considerable tumor regression. In addition, simultaneous inhibition of adaptive PD-L1 enrichment (due to negative-feedback to ICD induction) further leads to greater therapeutic outcome. Collectively, ER-targeted therapy can enhance anticancer efficacy by promoting ICD-associated immunotherapy, and potentiating chemotherapy and checkpoint blockade therapy.


Assuntos
Antígeno B7-H1 , Doxorrubicina , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Retículo Endoplasmático/metabolismo , Imunoterapia
3.
Biochem Biophys Res Commun ; 492(1): 82-88, 2017 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-28803985

RESUMO

Body fat mass is closely associated to diseases related to obesity. MicroRNAs (miRNAs, miR) are important regulatory molecules that function as post-transcriptional gene regulators of adipocyte development. In the current study, we revealed that reduced expression of miR-199a-3p in adipose tissue resulting from high fat diet (HFD)-induced obesity in mice. Overexpression of miR-199a-3p promoted adipocyte proliferation by regulating the expression of regulating factors of the cell cycle. Furthermore, miR-199a-3p blunted lipid accumulation in 3T3-L1 adipocytes. This was accompanied by a marked decrease in the expression of adipocyte-specific genes involved in lipogenic transcription, fatty acid synthesis, and fatty acid transportation. Furthermore, the fatty acid oxidation process was enhanced. Luciferase activity assays confirmed that miR-199a-3p regulates adipocyte differentiation by directly targeting the 3'-untranslated region (3'-UTR) of stearoyl-CoA desaturase (SCD). Moreover, miR-199a-3p regulates fatty acid composition by decreasing the ratio of unsaturated fatty acids (UFAs) in adipocytes transfected with miR-199a-3p mimics. These results suggest that miR-199a-3p may promote adipocyte proliferation, while also repressing adipocyte differentiation by down-regulating SCD and changing fatty acid composition during adipogenesis.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Diferenciação Celular/genética , Ácidos Graxos/metabolismo , MicroRNAs/genética , Estearoil-CoA Dessaturase/deficiência , Estearoil-CoA Dessaturase/genética , Células 3T3-L1 , Animais , Dieta Hiperlipídica , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Obesos
4.
Yi Chuan ; 39(10): 888-896, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29070484

RESUMO

As it is well known, proper exercise benefits our mind and body, especially the skeletal muscle. Exercise increases the capacity of muscle metabolism, enhances the biological function of mitochondria, regulates the transformation of muscle fiber types and increases the muscle power. In recent years, more and more researches show that epigenetic regulation plays an important role in strengthening the muscle, and these studies mainly include DNA methylation, histone modification, and regulation of miRNA expression. In order to adapt to the body movement, these three epigenetic patterns change the metabolic capacity of skeletal muscle, mitochondrial biological function and muscle fiber types by regulating the gene expression of skeletal muscle. In this review, we summarize research progresses of exercise-induced epigenetic regulation of gene expression of skeletal muscle, in order to provide a reference for further studies of how sports improve our body health.


Assuntos
Epigênese Genética , Exercício Físico , Regulação da Expressão Gênica , Músculo Esquelético/metabolismo , Metilação de DNA , Humanos
5.
Biochem Biophys Res Commun ; 475(1): 140-8, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27179777

RESUMO

MicroRNAs (miRNAs, miR) play important roles in adipocyte development. Recent studies showed that the expression of several miRNAs is closely related with promoter methylation. However, it is not known whether miRNA mediates adipocytes differentiation by means of DNA methylation. Here, we showed that miR-145a-5p was poorly expressed in adipose tissue from mice fed a high fat diet (HFD). Overexpression or inhibition of miR-145a-5p was unfavorable or beneficial, respectively, for adipogenesis, and these effects were achieved by regulating adipocyte-specific genes involved in lipogenic transcription, fatty acid synthesis, and fatty acid transportation. Particularly, we first suggested that miR-145a-5p mimics or inhibitors promoted or repressed adipocytes proliferation by regulating p53 and p21, which act as cell cycle regulating factors. Surprisingly, the miR-145a-5p-repressed adipocyte differentiation was enhanced or rescued when cells treated with 5-Aza-dC were transfected with miR-145a-5p mimics or inhibitors, respectively. These data indicated that, as a new mean to positively regulate adipocyte proliferation, the process of miR-145a-5p-inhibited adipogenesis may be regulated by DNA methylation.


Assuntos
Adipócitos/citologia , Adipogenia , Metilação de DNA , MicroRNAs/genética , Células 3T3-L1 , Adipócitos/metabolismo , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Proliferação de Células , Regulação da Expressão Gênica , Masculino , Camundongos , Regiões Promotoras Genéticas
6.
Injury ; 55(3): 111256, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38049367

RESUMO

PURPOSE: The objective of this study was to measure the morphological characteristics of inferior pole fracture of the patella (IPFP) and develop a practical classification system to determine the corresponding treatment protocols for different IPFPs with specific patterns. METHODS: A retrospective radiographic review was performed on a series of 71 patients with IPFP. The preoperative CT data were collected and measured using image processing software. The number of fragments, maximum fracture fragment anteroposterior length (MFFAL), maximum fracture fragment transverse length (MFFTL), fracture fragment coronal angle (FFCA), fracture fragment sagittal angle (FFSA), maximum fracture fragment height (MFFH) and maximum transverse sectional area (MTSA) were analysed. RESULTS: The mean number of fracture fragments was 3.8. The average MFFAL was 14.9 mm, the average MFFTL was 23.5 mm, the average FFCA was 92.1°, the average FFSA was 93.0°, the average MFFH was 13.6 mm, and the average MTSA was 299.3 mm2. A new classification system was introduced to describe the varied patterns of IPFP, summarized as (I) simple IPFP; (II) comminuted IPFP; (III) simple IPFP with simple patellar body fracture; and (IV) comminuted patellar fracture involving the inferior pole. With the four-type classification system, 12 type I, 22 type II, 21 type III, and 16 type IV lesions were observed, each with specific morphological characteristics. CONCLUSION: Most IPFPs exhibited a diversiform pattern, demonstrating that coverage fixation was likely needed. The four-type classification system might offer a valuable approach to help orthopaedic surgeons make individual treatment plans.


Assuntos
Fraturas Ósseas , Fraturas Cominutivas , Traumatismos do Joelho , Humanos , Fixação Interna de Fraturas/métodos , Patela/diagnóstico por imagem , Patela/cirurgia , Estudos Retrospectivos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Fraturas Cominutivas/cirurgia , Tomografia , Computadores , Fios Ortopédicos
7.
Nat Commun ; 15(1): 2763, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553476

RESUMO

The binding of therapeutic antagonists to their receptors often fail to translate into adequate manipulation of downstream pathways. To fix this 'bug', here we report a strategy that stitches cell surface 'patches' to promote receptor clustering, thereby synchronizing subsequent mechano-transduction. The "patches" are sewn with two interactable nanothreads. In sequence, Nanothread-1 strings together adjacent receptors while presenting decoy receptors. Nanothread-2 then targets these decoys multivalently, intertwining with Nanothread-1 into a coiled-coil supramolecular network. This stepwise actuation clusters an extensive vicinity of receptors, integrating mechano-transduction to disrupt signal transmission. When applied to antagonize chemokine receptors CXCR4 expressed in metastatic breast cancer of female mice, this strategy elicits and consolidates multiple events, including interception of metastatic cascade, reversal of immunosuppression, and potentiation of photodynamic immunotherapy, reducing the metastatic burden. Collectively, our work provides a generalizable tool to spatially rearrange cell-surface receptors to improve therapeutic outcomes.


Assuntos
Quimiocina CXCL12 , Neoplasias , Feminino , Animais , Camundongos , Quimiocina CXCL12/metabolismo , Transdução de Sinais , Receptores CXCR4/metabolismo , Movimento Celular , Metástase Neoplásica , Linhagem Celular Tumoral
8.
J Bone Joint Surg Am ; 106(11): 1008-1018, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38683886

RESUMO

➤ The concept of anteromedial cortical support (AMCS) serves as valuable guidance for the intraoperative reduction of trochanteric hip fractures.➤ Positive medial cortical support (MCS) and positive or neutral anterior cortical support (ACS) are desirable. Some evidence has suggested that positive MCS is potentially superior to neutral MCS.➤ Experimental studies underscore the vital importance of the anteromedial wall and reveal why positive MCS potentially outperforms neutral MCS.➤ Incorporating the AMCS concept, the Chang reduction quality criteria (CRQC) are a reliable alternative approach to evaluate the reduction quality of trochanteric hip fractures.


Assuntos
Fraturas do Quadril , Humanos , Fraturas do Quadril/cirurgia , Fixação Interna de Fraturas/métodos
9.
Adv Sci (Weinh) ; 11(13): e2307030, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38279587

RESUMO

Allogeneic tumor cell vaccines provide off-the-shelf convenience but lack patient specificity due to heterogeneity in tumor antigens. Here, allogeneic tumor cell corpses are converted into "zombie cells" capable of assimilating heterogeneous tumor by seizing cancer cells and spreading adjuvant infection. This causes pseudo-oncolysis of tumors, transforming them into immunogenic targets for enhanced phagocytosis. It is shown that in postoperative tumor models, localized delivery of premade "zombie cells" through stepwise gelation in resection cavity consolidates tumor surgery. Compared to analogous vaccines lacking "seizing" or "assimilating" capability, "zombie cell" platform effectively mobilizes T cell response against residual tumors, and establishes immunological memory against tumor re-challenge, showing less susceptibility to immune evasion. Despite using allogeneic sources, "zombie cell" platform functions as generalizable framework to produce long-term antitumor immunity in different tumor models, showing comparable effect to autologous vaccine. Together, with the potential of off-the-shelf availability and personalized relevance to heterogenous tumor antigens, this study suggests an alternative strategy for timely therapy after tumor surgery.


Assuntos
Vacinas Anticâncer , Transplante de Células-Tronco Hematopoéticas , Neoplasias , Humanos , Neoplasias/terapia , Imunoterapia , Antígenos de Neoplasias
10.
Orthop Surg ; 16(4): 930-942, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438157

RESUMO

OBJECTIVE: Dual-plate fixation was thought to be the gold standard for treating complicated bicondylar tibial plateau fractures, yet it was found to be hard to accommodate the posterior column in three-column fractures. Currently, column-specific fixation is becoming more and more recognized, but no comprehensive investigation has been performed to back it up. Therefore, the objective of this study was to validate the importance of posterior column fixation in the three-column tibial fractures by a finite element (FE) analysis and clinical study. METHODS: In FE analysis, three models were developed: the longitudinal triple-plate group (LTPG), the oblique triple-plate group (OTPG), and the dual-plate group (DPG). Three loading scenarios were simulated. The distribution of the displacement and the equivalent von Mises stress (VMS) in each structure was calculated. The comparative measurements including the maximum posterior column collapse (MPCC), the maximum total displacement of the model (MTD), the maximum VMS of cortical posterior column (MPC-VMS), and the maximum VMS located on each group of plates and screws (MPS-VMS). The clinical study evaluated the indicators between the groups with or without the posterior plate, including operation time, blood loss volume, full-weight bearing period, Hospital for Special Surgery Knee Scoring system (HSS), Rasmussen score, and common postoperative complications. RESULTS: In the FE analysis, the MPCC, the MPC-VMS, and the MTD were detected in much lower amounts in LTPG and OTPG than in DPG. In comparison with DPG, the LTPG and OTPG had larger MPS-VMS. In the clinical study, 35 cases were included. In the triple-plate (14) and dual-plate (21) groups, the operation took 115.6 min and 100.5 min (p < 0.05), respectively. Blood loss in both groups was 287.0 mL and 206.6 mL (p < 0.05), and the full-weight bearing period was 14.5 weeks and 16.2 weeks (p < 0.05). At the final follow-up, the HSS score was 85.0 in the triple-plate group and 77.5 in the dual-plate (p < 0.05), the Rasmussen score was 24.1 and 21.6 (p < 0.05), there were two cases with reduction loss (9.5%) in the dual-plate group and one case of superficial incision infection found in the triple-plate group. CONCLUSION: The posterior implant was beneficial in optimizing the biomechanical stability and functional outcomes in the three-column tibial plateau fractures.


Assuntos
Fraturas da Tíbia , Fraturas do Planalto Tibial , Humanos , Análise de Elementos Finitos , Fixação Interna de Fraturas , Fraturas da Tíbia/cirurgia , Placas Ósseas
11.
Int J Surg ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39017710

RESUMO

The posterolateral tibial plateau is crucial for maintaining knee stability during flexion, and fractures in this area often involve ligament and meniscus injuries, necessitating effective management. However, treating posterolateral tibial plateau fractures (PLF) poses significant challenges due to the complex anatomy. Therefore, this review aims to explore contemporary concepts of PLF, from identification to fixation, and proposes a comprehensive treatment strategy. In this article, the authors detail the injury mechanisms, fracture morphology, PLF classification systems, surgical approaches, and techniques for open reduction and internal fixation (ORIF) as well as arthroscopic-assisted internal fixation (ARIF). The findings indicate that PLF is typically caused by flexion-valgus forces, resulting in depression or split-depression patterns. For isolated PLF, the supra-fibular head approach is often preferable, whereas posterior approaches are more suitable for combined fractures. Additionally, innovative plates, particularly the horizontal belt plate, have shown satisfactory outcomes in treating PLF. Currently, the 'bicondylar four-quadrant' concept is widely used for assessing and managing the tibial plateau fractures involving PLF, forming the cornerstone of the comprehensive treatment strategy. Despite challenges in surgical exposure and implant placement, ORIF remains the mainstream treatment for PLF, benefiting significantly from the supra-fibular head approach and the horizontal belt plate. Furthermore, ARIF has proven effective by providing enhanced visualization and surgical precision in managing PLF, emerging as a promising technique.

12.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(1): 115-119, 2023 Jan 15.
Artigo em Zh | MEDLINE | ID: mdl-36708124

RESUMO

Objective: To summarize the surgical treatment methods and progress of inferior patellar pole fractures and provide reference for clinical application. Methods: The literature on surgical treatment of inferior patellar pole fractures was extensively reviewed, and the relevant research progress, advantages, and limitations were summarized. Results: The inferior pole of the patella is an important part of the knee extension device, which can strengthen the force arm of the quadriceps. Inferior patellar pole fractures are relatively rare and often comminuted, usually requiring surgical treatment. At present, there are various methods to treat inferior patellar pole fractures, including patellectomy of inferior pole, tension-band wiring technique, plate internal fixation, suture anchor fixation, claw-like shape memory alloy, separate vertical wiring technique. Different methods have their own characteristics, advantages, and disadvantages. The single internal fixation method has more complications and is easy to cause fixation failure. Therefore, the trend of combining various internal fixation methods is developing at present. Conclusion: When the main fragment of the inferior patellar pole fracture is large and mainly distributed transversely, the combination protocol based on tension-band wiring technique can be regarded as an ideal choice. When the fragments are severely damaged and small, the comprehensive protocol based on suture fixation can result in a better postoperative functional recovery.


Assuntos
Fraturas Ósseas , Fraturas Cominutivas , Traumatismos do Joelho , Humanos , Patela/cirurgia , Estudos Retrospectivos , Fraturas Ósseas/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Cominutivas/cirurgia , Traumatismos do Joelho/cirurgia , Fios Ortopédicos , Resultado do Tratamento
13.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(3): 290-295, 2023 Mar 15.
Artigo em Zh | MEDLINE | ID: mdl-36940986

RESUMO

Objective: To compare the biomechanical differences among the three novel internal fixation modes in treatment of bicondylar four-quadrant fractures of the tibial plateau through finite-element technique, and find an internal fixation modes which was the most consistent with mechanical principles. Methods: Based on the CT image data of the tibial plateau of a healthy male volunteer, a bicondylar four-quadrant fracture model of the tibial plateau and three experimental internal fixation modes were established by using finite element analysis software. The anterolateral tibial plateaus of groups A, B, and C were fixed with inverted L-shaped anatomic locking plates. In group A, the anteromedial and posteromedial plateaus were longitudinally fixed with reconstruction plates, and the posterolateral plateau was obliquely fixed with reconstruction plate. In groups B and C, the medial proximal tibia was fixed with T-shaped plate, and the posteromedial plateau was longitudinally fixed with the reconstruction plate or posterolateral plateau was obliquely fixed with the reconstruction plate, respectively. An axial load of 1 200 N was applied to the tibial plateau (a simulation of a 60 kg adult walking with physiological gait), and the maximum displacement of fracture and maximum Von-Mises stress of the tibia, implants, and fracture line were calculated in 3 groups. Results: Finite element analysis showed that the stress concentration area of tibia in each group was distributed at the intersection between the fracture line and screw thread, and the stress concentration area of the implant was distributed at the joint of screws and the fracture fragments. When axial load of 1 200 N was applied, the maximum displacement of fracture fragments in the 3 groups was similar, and group A had the largest displacement (0.74 mm) and group B had the smallest displacement (0.65 mm). The maximum Von-Mises stress of implant in group C was the smallest (95.49 MPa), while that in group B was the largest (177.96 MPa). The maximum Von-Mises stress of tibia in group C was the smallest (43.35 MPa), and that in group B was the largest (120.50 MPa). The maximum Von-Mises stress of fracture line in group A was the smallest (42.60 MPa), and that in group B was the largest (120.50 MPa). Conclusion: For the bicondylar four-quadrant fracture of the tibial plateau, a T-shaped plate fixed in medial tibial plateau has a stronger supporting effect than the use of two reconstruction plates fixed in the anteromedial and posteromedial plateaus, which should be served as the main plate. The reconstruction plate, which plays an auxiliary role, is easier to achieve anti-glide effect when it is longitudinally fixed in posteromedial plateau than obliquely fixed in posterolateral plateau, which contributes to the establishment of a more stable biomechanical structure.


Assuntos
Tíbia , Fraturas da Tíbia , Humanos , Adulto , Masculino , Tíbia/cirurgia , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia , Análise de Elementos Finitos , Fixação Interna de Fraturas/métodos , Placas Ósseas , Fenômenos Biomecânicos
14.
Injury ; 54(4): 1203-1209, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36754702

RESUMO

PURPOSE: To evaluate the feasibility and clinical outcomes of tension-band wiring through a single cannulated screw combined with two suture anchors in treating inferior pole fracture of the patella. METHODS: Between September 2018 and September 2021, a total of 22 patients with a mean age of 55 years who sustained inferior pole fracture of the patella and were treated by tension-band wiring through a single cannulated screw combined with two suture anchors were enrolled. X-ray radiographs were performed to observe the bone union time. The duration of each operation was recorded to reflect the complexity of surgical treatment. Functional measurements, comprising range of motion (ROM), the Böstman scale, and the Knee Injury and Osteoarthritis Outcome Score (KOOS), were taken. Postoperative complications including fixation failure, incision infection, loss of reduction, and malunion were evaluated. RESULTS: All patients were followed up for an average of 17 months (range: 12-25 months). The average clinical bone union time was 8 weeks (range: 6-12 weeks), and the radiographic bone union time was 11 weeks (range: 8-12 weeks). At the final follow-up, the mean ROM was 136° (range: 115°-140°), the KOOS was 85 (range: 68-100) and the Böstman score was 28 (range: 20-30); these outcomes were classified as excellent in 17 cases and good in 5 cases, with no instances of poor results. Loss of reduction occurred in one case, while no cases of incision infection, fixation failure or malunion were observed. CONCLUSION: For inferior pole fracture of the patella, tension-band wiring through a single cannulated screw combined with suture anchors can offer sufficient fixation stability to achieve a satisfactory clinical outcome with reduced operational complexity; this procedure should be recommended in clinical practice.


Assuntos
Fraturas Ósseas , Patela , Humanos , Pessoa de Meia-Idade , Patela/diagnóstico por imagem , Patela/cirurgia , Patela/lesões , Âncoras de Sutura , Fios Ortopédicos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Fixação Interna de Fraturas/métodos , Parafusos Ósseos , Infecção da Ferida Cirúrgica , Resultado do Tratamento
15.
Adv Sci (Weinh) ; 10(23): e2301434, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37290058

RESUMO

Strategies that induce dysfunction in the endoplasmic reticulum (ER) hold great promise for anticancer therapy, but remain unsatisfactory due to the compensatory autophagy induction after ER disruption. Moreover, as autophagy can either promote or suppress cell survival, which direction of autophagy better suits ER-targeting therapy remains controversial. Here, a targeted nanosystem is constructed, which efficiently escorts anticancer therapeutics into the ER, triggering substantial ER stress and autophagy. Concurrently, an autophagy enhancer or inhibitor is combined into the same nanoparticle, and their impacts on ER-related activities are compared. In the orthotopic breast cancer mouse model, the autophagy enhancer increases the antimetastasis effect of ER-targeting therapy and suppresses over 90% of cancer metastasis, while the autophagy inhibitor has a bare effect. Mechanism studies reveal that further enhancing autophagy accelerates central protein snail family transcriptional repressor 1 (SNAI1) degradation, suppressing downstream epithelial-mesenchymal transition, while inhibiting autophagy does the opposite. With the same trend, ER-targeting therapy combined with an autophagy enhancer provokes stronger immune response and tumor inhibition than the autophagy inhibitor. Mechanism studies reveal that the autophagy enhancer elevates Ca2+ release from the ER and functions as a cascade amplifier of ER dysfunction, which accelerates Ca2+ release, resulting in immunogenic cell death (ICD) induction and eventually triggering immune responses. Together, ER-targeting therapy benefits from the autophagy-enhancing strategy more than the autophagy-inhibiting strategy for antitumor and antimetastasis treatment.


Assuntos
Chaperona BiP do Retículo Endoplasmático , Retículo Endoplasmático , Camundongos , Animais , Retículo Endoplasmático/metabolismo , Morte Celular , Autofagia/fisiologia , Estresse do Retículo Endoplasmático
16.
J Control Release ; 363: 402-414, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37751825

RESUMO

Post-surgical efferocytosis of tumor associated macrophages (TAMs) originates an immunosuppressive tumor microenvironment and facilitates abscopal metastasis of residual tumor cells. Currently, few strategies could inhibit efferocytosis while recovering the tumor-eliminative phagocytosis of TAMs. Herein, we developed an in situ hydrogel that contains anti-CD47 antibody (aCD47) and apocynin (APO), an inhibitor of nicotinamide adenine dinucleotide phosphate oxidase. This hydrogel amplifies the non-efferocytic phagocytosis of TAMs by (1) blocking the extracellular "Don't eat me" signal of efferocytosis with aCD47, which enhances the receptor-mediated recognition and engulfment of tumor cells by TAMs in the post-surgical tumor bed, and (2) by utilizing APO to dispose of tumor debris in a non-efferocytic manner, which prevents acidification and maturation of efferosomes and allows for M1-polarization of TAMs, leading to improved antigen presentation ability. With the complementary intervention of extracellular and intracellular, this hydrogel reverses the immunosuppressive effects of efferocytosis, and induces a potent M1-associated Th1 immune response against tumor recurrence. In addition, the in situ detachment and distal colonization of metastatic tumor cells were efficiently restrained due to the intervention of efferocytosis. Collectively, the hydrogel potentiates surgery treatment of tumor by recovering the tumor-elimination ability of post-surgical TAMs.


Assuntos
Macrófagos , Neoplasias , Humanos , Hidrogéis/farmacologia , Fagocitose , Neoplasias/patologia , Microambiente Tumoral
17.
J Control Release ; 352: 747-758, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36356942

RESUMO

The abnormal metabolism of rapidly growing tumors can create an acidic tumor microenvironment (TME) that renders cancer cells resistant to chemotherapy and further facilitates endothelial-to-mesenchymal transition (EMT) progress to promote metastasis. Here, we developed a combination strategy consisting of (1) peritumorally injected scaffold that alleviates TME acidosis, and (2) intravenously injected nanoparticles that delivers anti-cancer agents to tumor. Concurrent treatment with these two drug delivery systems profoundly delayed the growth of primary tumor and reduced the spontaneous metastasis to lung in an orthotopic breast cancer mouse model. Mechanism studies both in vitro and in vivo further revealed that neutralization of TME pH by the hydrogel scaffold sensitized cancer cells to nanoparticle-based chemotherapy, thereby strengthening the cytotoxicity against tumor growth; In parallel, reversal of tumor acidity downregulated various pro-metastatic proteins intratumorally to block the EMT progress, thereby reducing the metastatic potential of cancer cells. This work provided proof-of-concept demonstration that chemotherapy sensitization and EMT suppression could be synchronized by the modulation of TME pH, which may be potentially beneficial for simultaneous inhibition of tumor growth and cancer metastasis.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Camundongos , Animais , Microambiente Tumoral , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Metástase Neoplásica/tratamento farmacológico
18.
J Control Release ; 347: 199-210, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35550911

RESUMO

Dendritic cells (DCs) play central role in adaptive antitumor immunity, while their function is often hampered by low immunogenicity of tumor tissues and surrounding hostile microenvironment. Herein, a "split bullets" loaded nanoplatform that can bidirectionally injure mitochondria (MT) and endoplasmic reticulum (ER) of tumor cells is developed. After cellular uptake, the released "split bullets" separately target to different subcellular destinations and exert distinct effects on DCs: (1) MT-targeted "bullet" recruits peripheral DCs into tumor sites, due to its capability to trigger adenosine triphosphate release from tumor cells; (2) ER-targeted "bullet" activates tumor-infiltrating DCs, which is attributed to its ability to evoke calreticulin exposure on tumor cells. These effects collectively improve the tropism and reactivity of DCs to tumor-specific antigen in a two-pronged way. As a result of enhanced function of DCs in antigen capture, treatment of the "split bullets" loaded nanoplatform ignites robust immune response to suppress primary melanoma, and establishes systemic immune memory against post-surgical tumor recurrence. Overall, this nanoplatform offers a generalizable approach to boost DCs and augment immunotherapy.


Assuntos
Vacinas Anticâncer , Melanoma , Nanopartículas , Imunidade Adaptativa , Células Dendríticas , Humanos , Fatores Imunológicos , Imunoterapia , Microambiente Tumoral
19.
ACS Nano ; 16(4): 6064-6079, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35344338

RESUMO

Tumor surgery can create an inflammatory trauma to aggravate residual tumor "seed" to colonize pre-metastatic niches (PMNs) "soil" at secondary sites, thereby promoting post-operative metastasis. However, two-pronged strategies for post-surgical elimination of asynchronous "seeds" and "soil" at different regions are currently lacking. Here, we have designed a hydrogel that can be injected into a resection cavity, where it immediately forms a scaffold and gradually degrades responding to enriched reactive oxygen species at adjacent trauma for local delivery and on-demand release of autologous cancer cells succumbing to oncolysis (ACCO) and anti-inflammatory agent. The autologous cell source self-provides a whole array of tumor-associated antigens, and the oncolysis orchestration of a subcellular cascade confers a self-adjuvanting property, together guaranteeing high immunogenicity of the ACCO vaccine that enables specific antitumor immunization. In parallel, inflammation alleviation exerted bidirectional functions to reshape the local immune landscape and resuscitate ACCO, leading to the eradication of residual tumor "seeds" while simultaneously intercepting the "seed-soil" crosstalk to normalize distant lung leading to regression of pre-existing PMN "soil". As a result, regional and metastatic recurrence were completely thwarted. Together, this framework synchronizing oncolysis immunization and inflammation alleviation provides an effective option for post-operative suppression of metastasis.


Assuntos
Hidrogéis , Inflamação , Humanos , Neoplasia Residual , Imunização , Metástase Neoplásica
20.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4183-4184, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-25600741

RESUMO

Liangshan pig is one of the famous native breeds in Sichuan province in China. It lives in the mountainous areas (about 1500-2500 m altitude) and has a superior meat quality. Here, the complete mitochondrial genome sequence of Liangshan pig was first reported. The total length of mitochondrial genome is 16,760 bp, including 34.62% A, 25.79% T, 26.20%, C and 13.39% G, with an A + T bias of 60.41%. Mitochondrial genome contains a major non-coding control region (D-Loop region), two ribosomal RNA genes, 13 protein-coding genes (PCGs), and 22 transfer RNA genes. The D-loop region is located between the tRNA-Pro and tRNA-Phe genes with a length of 1324 bp, some tandem repeat sequences was found in the region. The mitochondrial genome of Liangshan pig provides an important role in genetic mechanism.


Assuntos
Mitocôndrias/genética , Análise de Sequência de DNA/métodos , Sus scrofa/genética , Animais , Composição de Bases , China , Ordem dos Genes , Tamanho do Genoma , Genoma Mitocondrial , Fases de Leitura Aberta , RNA Ribossômico/genética , RNA de Transferência/genética
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