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1.
BMC Cancer ; 24(1): 1247, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385104

RESUMO

BACKGROUND: Neoadjuvant chemoradiotherapy followed by total mesorectal excision is a standard treatment for locally advanced rectal cancer. Mismatch repair-deficient locally advanced rectal cancer (LARC) was highly sensitive to PD-1 blockade. However, most rectal cancers are microsatellite stable (MSS) or mismatch repair-proficient (pMMR) subtypes for which PD-1 blockade is ineffective. Radiation can trigger the activation of CD8 + T cells, further enhancing the responses of MSS/pMMR rectal cancer to PD-1 blockade. Radioimmunotherapy offers a promising therapeutic modality for rectal cancer. Progenitor T exhausted cells are abundant in tumour-draining lymph nodes and play an important role in immunotherapy. Conventional irradiation fields include the mesorectum and regional lymph nodes, which might cause considerable damage to T lymphocytes and radiation-induced fibrosis, ultimately leading to a poor response to immunotherapy and rectal fibrosis. This study investigated whether node-sparing modified short-course irradiation combined with chemotherapy and PD-1 blockade could be effective in patients with MSS/ pMMR LARC. METHODS: This was a open-label, single-arm, multicentre, prospective phase II trial. 32 LARC patients with MSS/pMMR will receive node-sparing modified short-course radiotherapy (the irradiated planned target volume only included the primary tumour bed but not the tumour-draining lymph nodes, 25 Gy/5f, 5 Gy/f) followed by CAPOX and tislelizumab. CAPOX and tislelizumab will be started two days after the completion of radiotherapy: oxaliplatin 130 mg/m2 intravenous infusion, day 1; capecitabine 1000 mg/m2 oral administration, days 1-14; and tislelizumab 200 mg, intravenous infusion, day 1. There will be four 21-day cycles. TME will be performed at weeks 14-15. We will collect blood, tumour, and lymphoid specimens; perform flow cytometry and in situ multiplexed immunofluorescence detection; and analyse the changes in various lymphocyte subsets. The primary endpoint is the rate of pathological complete response. The organ preservation rate, tumour regression grade, local recurrence rate, disease-free survival, overall survival, adverse effects, and quality of life will also be analysed. DISCUSSION: In our research, node-sparing modified radiotherapy combined with immunotherapy probably increased the responsiveness of immunotherapy for MSS/pMMR rectal cancer patients, reduced the occurrence of postoperative rectal fibrosis, and improved survival and quality of life. This is the first clinical trial to utilize a node-sparing radiation strategy combined with chemotherapy and PD-1 blockade in the neoadjuvant treatment of rectal cancer, which may result in a breakthrough in the treatment of MSS/pMMR rectal cancer. TRIAL REGISTRATION: This study was registered at www. CLINICALTRIALS: gov . TRIAL REGISTRATION NUMBER: NCT05972655. Date of registration: 31 July 2023.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias Retais , Humanos , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Neoplasias Retais/radioterapia , Neoplasias Retais/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Estudos Prospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Oxaliplatina/uso terapêutico , Oxaliplatina/administração & dosagem , Quimiorradioterapia/métodos , Masculino , Capecitabina/uso terapêutico , Capecitabina/administração & dosagem , Feminino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Adulto
2.
Dis Colon Rectum ; 65(8): 1062-1068, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35421009

RESUMO

BACKGROUND: Anastomotic stenosis is a common complication of colorectal cancer surgery with anastomosis. Transanal minimally invasive surgery is a novel approach to the treatment of anastomotic stenosis. OBJECTIVE: This study aimed to evaluate the efficacy and safety of transanal minimally invasive surgery for anastomotic stenosis treatment. DESIGN: This was a retrospective study. SETTINGS: This study was conducted at a comprehensive cancer center. PATIENTS: This study included patients with rectal anastomotic stenosis who after undergoing colorectal surgery were admitted to the Sir Run Run Shaw Hospital between September 2017 and June 2019. MAIN OUTCOME MEASURES: The primary outcome was the operative success rate. The secondary outcomes were intraoperative variables, postoperative complications, stoma closure conditions, and stenosis recurrence risks. RESULTS: Nine patients, aged 52 to 80 years, with a history of colorectal cancer with end-to-end anastomosis underwent transanal minimally invasive surgery for anastomotic stenosis. The distance between the stenosis and the anal verge ranged from 5 to 12 cm. The mean stenosis diameter was 0.3 cm. Four patients had completely obstructed rectal lumens. Eight of 9 patients successfully underwent transanal minimally invasive surgery radial incision and cutting. The average operation time was 50 minutes. After the procedure, 1 patient had symptomatic procedure-associated perforations but recovered with conservative treatment. No perioperative mortality occurred. One patient underwent transverse colostomy 1 month after transanal minimally invasive surgery because of proximal colon ischemia induced by primary rectal surgery. Eight patients underwent protective loop ileostomy. After transanal minimally invasive surgery, stoma closure was performed in 88% of patients with no stenosis recurrence or obstruction at follow-up (21-42 mo). LIMITATIONS: This study was limited by its small sample size and single-center design. CONCLUSIONS: Transanal minimally invasive surgery provides an excellent operative field, good maneuverability, and versatile instrumentation and is a safe and effective treatment for rectal anastomotic stenosis, especially for severe fibrotic stenosis or complete obstruction. See Dynamic Article Video at http://links.lww.com/DCR/B965 .


Assuntos
Neoplasias Retais , Cirurgia Endoscópica Transanal , Canal Anal/cirurgia , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/etiologia , Fístula Anastomótica/cirurgia , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Humanos , Complicações Pós-Operatórias , Neoplasias Retais/cirurgia , Reto/cirurgia , Estudos Retrospectivos , Cirurgia Endoscópica Transanal/efeitos adversos
3.
Langenbecks Arch Surg ; 407(4): 1751-1756, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35034165

RESUMO

BACKGROUND: Anastomotic leakage (AL) is a severe complication of rectal cancer low anterior resection (LAR). Ileostomy, the most common method to reduce the severity of AL, is associated with the risk of permanent stoma and an additional operation for stoma reversal. This purpose of this study is to develop a novel protective technique called the stent-based diverting technique (SDT) to protect the anastomosis following LAR. METHODS: From March 2020 to December 2020, thirty-four patients treated with LAR followed by SDT were enrolled prospectively at Sir Run Run Shaw Hospital. Demographic characteristics, laboratory test results, surgical outcomes, and oncological features were recorded. RESULTS: Overall, the median period of stent degradation was 21 (18-24) days. One patient (2.9%) had anastomotic leakage, and another patient (2.9%) had intestinal obstruction, while no other complications (e.g., intestinal volvulus, perforation, fistula) were observed in this study. CONCLUSIONS: The unique SDT may be a novel approach to prevent anastomotic leakage following low anterior resection of rectal cancer.


Assuntos
Neoplasias Retais , Estomas Cirúrgicos , Anastomose Cirúrgica/métodos , Fístula Anastomótica/etiologia , Fístula Anastomótica/prevenção & controle , Fístula Anastomótica/cirurgia , Humanos , Ileostomia/métodos , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Stents/efeitos adversos
4.
EMBO Rep ; 19(10)2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30126922

RESUMO

Progressive attrition of telomeres triggers DNA damage response (DDR) and limits the regenerative capacity of adult stem cells during mammalian aging. Intriguingly, telomere integrity is not only determined by telomere length but also by the epigenetic status of telomeric/sub-telomeric regions. However, the functional interplay between DDR induced by telomere shortening and epigenetic modifications in aging remains unclear. Here, we show that deletion of Gadd45a improves the maintenance and function of intestinal stem cells (ISCs) and prolongs lifespan of telomerase-deficient mice (G3Terc-/-). Mechanistically, Gadd45a facilitates the generation of a permissive chromatin state for DDR signaling by inducing base excision repair-dependent demethylation of CpG islands specifically at sub-telomeric regions of short telomeres. Deletion of Gadd45a promotes chromatin compaction in sub-telomeric regions and attenuates DDR initiation at short telomeres of G3Terc-/- ISCs. Treatment with a small molecule inhibitor of base excision repair reduces DDR and improves the maintenance and function of G3Terc-/- ISCs. Taken together, our study proposes a therapeutic approach to enhance stem cell function and prolong lifespan by targeting epigenetic modifiers.


Assuntos
Proteínas de Ciclo Celular/genética , Epigênese Genética/genética , Proteínas Nucleares/genética , RNA/genética , Telomerase/genética , Telômero/genética , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Ilhas de CpG/genética , Dano ao DNA/genética , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Knockout , Células-Tronco/metabolismo
5.
Surg Endosc ; 34(10): 4655-4661, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31741161

RESUMO

BACKGROUND: As a key landmark during laparoscopic right colectomy, the classification and variation of the gastrocolic trunk of Henle (GTH) remains to be clarified. The aim of this nationwide multicenter study was to describe the characteristics of the GTH intra-operatively during laparoscopic right colectomies. METHODS: Three hundred seventy-one patients who underwent laparoscopic right colectomies from January 2018 to March 2019 in 25 hospitals across China were enrolled in the study. The length of the GTH, the classification with a precise description of confluent tributaries, and other variations were analyzed. RESULTS: Of the 371 patients, 363 had a GTH. The proportion of type-0, type-I, type-II, and type-III was 15.2% (n = 55), 54.8% (n = 199), 25.3% (n = 92), and 4.7% (n = 17), respectively. The average length of the GTH was 8.5 mm, ranging from 2 to 30 mm. CONCLUSIONS: This is the first multicenter study with a large sample by which the GTH was classified based on laparoscopic intraoperative observation. Variations in the GTH were classified into four types based on the number of colic drainage veins (right colic, superior right colic, middle colic, accessory middle colic, and ileocolic veins), among which the right colic vein was the most common. The length of the GTH was relatively short, and thus might carry a risk of bleeding. Further clinical data should be correlated with the characteristics of the GTH.


Assuntos
Colectomia/métodos , Neoplasias do Colo/cirurgia , Laparoscopia/métodos , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino
6.
BMC Cancer ; 19(1): 629, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31238895

RESUMO

BACKGROUND: This study aimed to evaluate the value of chitinase activity in prognosticating the occurrence of metastasis in and prognosis of patients with colorectal cancer (CRC). METHODS: The chitinase activity in four different groups, namely 335 CRC patients without distant metastasis at their first visit (Group 1), 51 patients with CRC having synchronous liver metastasis (Group 2), 100 healthy age-matched controls (Group 3) and 40 patients with liver cancer (Group 4), were assayed using an enzyme-linked immunosorbent assay. The Cox proportional hazards ratio model and Kaplan-Meier curve were used to identify the association between chitinase activity and the clinical outcome of CRC patients without metastasis in the training set and testing set at their first visit. An in vitro Transwell experiment was performed to evaluate the migration of colon cancer cells. RESULTS: Patients with high chitinase activity had a significantly higher metastasis risk than those with low chitinase activity in the training and testing sets during follow-up, both at stage I/II and stage III. Further, multivariate analysis revealed that chitinase activity was an independent risk factor prognosticating liver metastases (P = 0.001). The combination of chitinase activity and lymph node metastasis status increased the accuracy of the prognosis of liver metastases after radical resection (P = 0.454E-011). In addition, chitinase promoted CRC cell migration in vitro. CONCLUSIONS: Chitinase activity can prognosticate the occurrence of metastasis in patients with CRC. Moreover, the combination of chitinase activity and N stage increased the power of prognosticating the occurrence of metastasis. Inhibiting chitinase activity may serve as a new strategy to treat metastases of CRC.


Assuntos
Quitinases/sangue , Neoplasias do Colo/enzimologia , Neoplasias do Colo/patologia , Neoplasias Hepáticas/secundário , Neoplasias Retais/enzimologia , Neoplasias Retais/patologia , Biomarcadores Tumorais/sangue , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular , Neoplasias do Colo/mortalidade , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Retais/mortalidade , Estudos Retrospectivos
7.
RNA Biol ; 16(8): 991-1000, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31107151

RESUMO

RNA epigenetics has received a great deal of attention in recent years, and the reversible N6-methyladenosine (m6A) modification on messenger RNAs (mRNAs) has emerged as a widespread phenomenon. The vital roles of m6A in diverse biological processes are dependent on many RNA-binding proteins (RBPs) with 'reader' or 'nonreader' functions. Moreover, m6A effector proteins affect cellular processes, such as stem cell differentiation, tumor development and the immune response by controlling signal transduction. This review provides an overview of the interactions of m6A with various RBPs, including the 'reader' proteins (excluding the YT521-B homology (YTH) domain proteins and the heterogeneous nuclear ribonucleoproteins (hnRNPs)), and the functional 'nonreader' proteins, and this review focuses on their specific RNA-binding domains and their associations with other m6A effectors. Furthermore, we summarize key m6A-marked targets in distinct signaling pathways, leading to a better understanding of the cellular m6A machinery.


Assuntos
Adenosina/análogos & derivados , Epigenômica , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Adenosina/genética , Humanos , Transdução de Sinais/genética
8.
Nucleic Acids Res ; 44(18): 8693-8703, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27325744

RESUMO

Angiogenesis is recognized as an important hallmark of cancer. Although telomerase is thought to be involved in tumor angiogenesis, the evidence and underlying mechanism remain elusive. Here, we demonstrate that human telomerase reverse transcriptase (hTERT) activates vascular epithelial growth factor (VEGF) gene expression through interactions with the VEGF promoter and the transcription factor Sp1. hTERT binds to Sp1 in vitro and in vivo and stimulates angiogenesis in a manner dependent on Sp1. Deletion of the mTert gene in the first generation of Tert null mice compromised tumor growth, with reduced VEGF expression. In addition, we show that hTERT expression levels are positively correlated with those of VEGF in human gastric tumor samples. Together, our results demonstrate that hTERT facilitates tumor angiogenesis by up-regulating VEGF expression through direct interactions with the VEGF gene and the Sp1 transcription factor. These results provide novel insights into hTERT function in tumor progression in addition to its role in telomere maintenance.


Assuntos
Neovascularização Patológica/metabolismo , Fator de Transcrição Sp1/metabolismo , Telomerase/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Células HeLa , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica/genética , Neoplasias Gástricas/irrigação sanguínea , Neoplasias Gástricas/genética , Transcrição Gênica , Regulação para Cima/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Cell Physiol Biochem ; 41(6): 2545-2552, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28472806

RESUMO

BACKGROUND: The published literature contains conflicting results regarding the impact of the glutathione S-transferase T1 (GSTT1) null genotype on the susceptibility to inflammatory bowel disease. Therefore, we conducted a meta-analysis of observational studies to assess the association. METHODS: We searched four online databases for eligible studies. The odds ratio (OR) with 95% CI was used to assess the gene-disease association. We also performed subgroup analyses by type of inflammatory bowel disease and ethnicity. RESULTS: There were 16 individual studies from 11 publications included in the analysis. There were 3366 cases with inflammatory bowel disease and 6013 controls. The meta-analysis of all 16 studies showed the GSTT1 null genotype was associated with increased susceptibility to inflammatory bowel disease (OR = 1.98, 95%CI 1.39-2.84, P < 0.001). The subgroup analysis by ethnicity further identified an association between the GSTT1 null genotype and inflammatory bowel disease in Caucasians, Asians, and Africans. The GSTT1 null genotype was associated with both ulcerative colitis (OR = 1.96, P = 0.004) and Crohn's disease (OR = 2.01, P = 0.022). The GSTT1 null genotype was still significantly associated with ulcerative colitis (OR = 1.63, P < 0.0001) and Crohn's disease (OR = 1.40, P = 0.023) after adjusting for study heterogeneity. CONCLUSION: The GSTT1 null genotype is significantly associated with an increased susceptibility to inflammatory bowel disease and is a risk factor for both ulcerative colitis and Crohn's disease.


Assuntos
Predisposição Genética para Doença , Glutationa Transferase/genética , Doenças Inflamatórias Intestinais/genética , Colite Ulcerativa/genética , Doença de Crohn/genética , Bases de Dados Factuais , Genótipo , Humanos , Razão de Chances , Fatores de Risco
10.
Hepatology ; 61(6): 2030-41, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25704606

RESUMO

UNLABELLED: The liver possesses extraordinary regenerative capacity in response to injury. However, liver regeneration (LR) is often impaired in disease conditions. Wild-type p53-induced phosphatase 1 (Wip1) is known as a tumor promoter and enhances cell proliferation, mainly by deactivating antioncogenes. However, in this work, we identified an unexpected role of Wip1 in LR. In contrast to its known role in promoting cell proliferation in extrahepatic tissue, we found that Wip1 suppressed hepatocyte proliferation after partial hepatectomy (PHx). Deletion of Wip1 increased the rate of LR after PHx. Enhanced LR in Wip1-deficient mice was a result of the activation of the mammalian target of rapamycin (mTOR) complex 1 (mTORC1) pathway. Furthermore, we showed that Wip1 physically interacted with and dephosphorylated mTOR. Interestingly, inhibition of Wip1 also activated the p53 pathway during LR. Disruption of the p53 pathway further enhanced LR in Wip1-deficient mice. Therefore, inhibition of Wip1 has a dual role in LR, i.e., promoting hepatocyte proliferation through activation of the mTORC1 pathway, meanwhile suppressing LR through activation of the p53 pathway. However, the proregenerative role of mTORC1 overwhelms the antiproliferative role of p53. Furthermore, CCT007093, a Wip1 inhibitor, enhanced LR and increased the survival rate of mice after major hepatectomy. CONCLUSION: mTOR is a new direct target of Wip1. Wip1 inhibition can activate the mTORC1 pathway and enhance hepatocyte proliferation after hepatectomy. These findings have clinical applications in cases where LR is critical, including acute liver failure, cirrhosis, or small-for-size liver transplantations.


Assuntos
Hepatócitos/fisiologia , Regeneração Hepática , Fosfoproteínas Fosfatases/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Proliferação de Células , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Hepatectomia , Sistema de Sinalização das MAP Quinases , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Complexos Multiproteicos/metabolismo , NF-kappa B/metabolismo , Proteína Fosfatase 2C , Proteína Supressora de Tumor p53/metabolismo
11.
Future Oncol ; 11(2): 193-203, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25040106

RESUMO

BACKGROUND: N-acetyl-glucosaminidase (NAG) is a potential marker of genotoxicity. We retrospectively analyzed plasma NAG and clinico-pathologic features in advanced gastrointestinal adenocarcinoma patients. METHODS: Plasma from 118 patients and 51 healthy volunteers was analyzed for associations between NAG levels and age, disease presence, stage, treatment responses and survival. RESULTS: Pretreatment NAG correlated with age but was independently increased in metastatic versus locally advanced disease, particularly in gastric/esophageal patients. NAG was also associated with reduced overall survival. In subgroup analysis, increased NAG activity between day 1 and 2 of chemotherapy cycle 1 correlated with treatment response. CONCLUSION: We demonstrated that NAG correlates with gastrointestinal cancer outcomes. Further studies are required to determine if plasma markers of genotoxicity can be useful for disease monitoring.


Assuntos
Acetilglucosaminidase/sangue , Adenocarcinoma/sangue , Neoplasias Colorretais/sangue , Neoplasias Esofágicas/sangue , Neoplasias Gástricas/sangue , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Estudos de Casos e Controles , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Resultado do Tratamento , Adulto Jovem
12.
Front Surg ; 11: 1388250, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38712335

RESUMO

Background: Colorectal cancer (CRC) is the third most common cancer worldwide. Patients diagnosed with stage I CRC typically do not require postoperative adjuvant treatment. However, postoperative recurrence is present in at least 40% of patients with CRC and often occurs in those with stage I disease. This study aimed to elucidate the current status of recurrence and clinicopathological characteristics in patients with stage I CRC. Methods: Data of indicated patients were obtained from 18 registries in Surveillance, Epidemiology, and End Results (SEER). The multivariable Fine-Gray regression model was used to identify the mortality risk of patients. Disparities in survival were analyzed using Kaplan-Meier curves. Logistic regression was employed to identify factors associated with recurrent risk overestimation. Results: Our study indicated a recurrence rate of 15.04% (1,874/12,452) in stage I CRC cases. Notably, we identified race, age, T stage, and carcinoembryonic antigen (CEA) levels as independent risk factors for tumor recurrence, substantially impacting prognosis. Furthermore, gender, race (Black), age (>65 years), elevated CEA levels, and refusal or unknown status regarding radiotherapy significantly correlated with an adverse prognosis in patients with stage I CRC. Conclusions: We identified certain key clinicopathological features of patients with stage I CRC and demonstrated the survival benefits of radiotherapy, offering a new perspective on stage I CRC follow-up and treatment recommendations.

13.
J Clin Invest ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39436710

RESUMO

BRAFV600E-mutant metastatic colorectal cancer (mCRC) is associated with poor prognosis. The combination of anti-BRAF/EGFR (encorafenib/cetuximab) treatment for patients with BRAFV600E-mutant mCRC improved clinical benefits; unfortunately, inevitable acquired resistance limits the treatment outcome, and the mechanism has not been validated. Here, we discovered that monoacylglycerol O-Acyltransferase 3 (MOGAT3) mediated diacylglycerol (DAG) accumulation contributed to acquired resistance to encorafenib/cetuximab by dissecting BRAFV600E-mutant mCRC patient-derived xenograft (PDX) model exposed to encorafenib/cetuximab administration. Mechanistically, upregulated MOGAT3 promotes DAG synthesis and reduces fatty acid oxidation (FAO)-promoting DAG accumulation and activating PKCα-CRAF-MEK-ERK, driving acquired resistance. Resistance-induced hypoxia promotes MOGAT3 transcriptional elevation; simultaneously, MOGAT3-mediated DAG accumulation increases HIF1A expression in translation level through PKCα-CRAF-eIF4E activation, strengthening the resistance status. Intriguingly, reducing intratumoral DAG by fenofibrate or Pf-06471553 restores the antitumor efficacy of encorafenib/cetuximab on resistant BRAFV600E-mutant mCRC, interrupted PKCα-CRAF-MEK-ERK signaling. These findings reveal the critical metabolite DAG as a modulator of encorafenib/cetuximab efficacy in BRAFV600E-mutant mCRC, suggesting that fenofibrate may prove beneficial for resistant BRAFV600E-mutant mCRC patients.

14.
Sci China Life Sci ; 67(9): 1881-1898, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38805063

RESUMO

Aberrant expression of circular RNAs (circRNAs) is frequently linked to colorectal cancer (CRC). Here, we identified circZFR as a promising biomarker for CRC diagnosis and prognosis. CircZFR was upregulated in CRC tissues and serum exosomes and its level was linked to cancer incidence, advanced-stages, and metastasis. In both in vitro and in vivo settings, circZFR promoted the growth and spread while suppressing apoptosis of CRC. Exosomes with circZFR overexpression promoted the proliferation and migration of cocultured CRC cells. Mechanistically, epithelial splicing regulatory protein 1 (ESRP1) in CRC cells may enhance the production of circZFR. BCL2-associated transcription factor 1 (BCLAF1) bound to circZFR, which prevented its ubiquitinated degradation. Additionally, circZFR sponged miR-3127-5p to boost rhotekin 2 (RTKN2) expression. Our TCP1-CD-QDs nanocarrier was able to carry and deliver circZFR siRNA (si-circZFR) to the vasculature of CRC tissues and cells, which inhibited the growth of tumors in patient-derived xenograft (PDX) models. Taken together, our results show that circZFR is an oncogenic circRNA, which promotes the development and spread of CRC in a BCLAF1 and miR-3127-5p-dependent manner. CircZFR is a possible serum biopsy marker for the diagnosis and a desirable target for further treatment of CRC.


Assuntos
Proliferação de Células , Neoplasias Colorretais , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , MicroRNAs , RNA Circular , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Apoptose/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Exossomos/metabolismo , Exossomos/genética , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Prognóstico , Proteínas Repressoras , RNA Circular/genética , RNA Circular/metabolismo , Proteínas Supressoras de Tumor
15.
Cancer Res ; 84(20): 3371-3387, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39250301

RESUMO

Tumor stroma plays a critical role in fostering tumor progression and metastasis. Cancer-associated fibroblasts (CAF) are a major component of the tumor stroma. Identifying the key molecular determinants for the protumor properties of CAFs could enable the development of more effective treatment strategies. In this study, through analyses of single-cell sequencing data, we identified a population of CAFs expressing high levels of sulfatase 1 (SULF1), which was associated with poor prognosis in patients with colorectal cancer. Colorectal cancer models using mice with conditional SULF1 knockout in fibroblasts revealed the tumor-supportive function of SULF1+ CAFs. Mechanistically, SULF1+ CAFs enhanced the release of VEGFA from heparan sulfate proteoglycan. The increased bioavailability of VEGFA initiated the deposition of extracellular matrix and enhanced angiogenesis. In addition, intestinal microbiota-produced butyrate suppressed SULF1 expression in CAFs through its histone deacetylase (HDAC) inhibitory activity. The insufficient butyrate production in patients with colorectal cancer increased the abundance of SULF1+ CAFs, thereby promoting tumor progression. Importantly, tumor growth inhibition by HDAC was dependent on SULF1 expression in CAFs, and patients with colorectal cancer with more SULF1+ CAFs were more responsive to treatment with the HDAC inhibitor chidamide. Collectively, these findings unveil the critical role of SULF1+ CAFs in colorectal cancer and provide a strategy to stratify patients with colorectal cancer for HDAC inhibitor treatment. Significance: SULF1+ cancer-associated fibroblasts play a tumor-promoting role in colorectal cancer by stimulating extracellular matrix deposition and angiogenesis and can serve as a biomarker for the therapeutic response to HDAC inhibitors in patients.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Colorretais , Sulfotransferases , Microambiente Tumoral , Fator A de Crescimento do Endotélio Vascular , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Animais , Humanos , Camundongos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Sulfotransferases/metabolismo , Sulfotransferases/genética , Camundongos Knockout , Neovascularização Patológica/patologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/genética , Feminino , Microbioma Gastrointestinal , Butiratos/metabolismo , Butiratos/farmacologia , Linhagem Celular Tumoral , Prognóstico , Masculino
16.
Exp Hematol Oncol ; 13(1): 90, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198883

RESUMO

BACKGROUND: Peritoneal metastases frequently occur in epithelial ovarian cancer (EOC), resulting in poor prognosis and survival rates. Tumor-associated-macrophages (TAMs) massively infiltrate into ascites spheroids and are multi-polarized as protumoral M2-like phenotype, orchestrating the immunosuppression and promoting tumor progression. However, the impact of omental conditioned medium/ascites (OCM/AS) on TAM polarization and its function in tumor progression remains elusive. METHODS: The distribution and polarization of TAMs in primary and omental metastatic EOC patients' tumors and ascites were examined by m-IHC, FACS analysis, and immunofluorescence. QPCR, immunofluorescence, FACS analysis, lipid staining assay, ROS assay, and Seahorse real-time cell metabolic assay characterized TAMs as being polarized in the ascites microenvironment. The oncogenic role of TAMs in tumor cells was demonstrated by co-cultured migration/invasion, proliferation, and spheroid formation assays. Mechanistic studies of the regulations of TAM polarization were performed by using RNA-Seq, GTPase pull-down, G-LISA activation assays, and other biochemical assays. A Yap1 macrophages (MФs) conditional knockout (cKO) mouse model demonstrated the roles of YAP1 in TAM polarization status and its pro-metastatic function. Finally, the anti-metastatic potential of targeting TAMs through restoring YAP1 by pharmacological agonist XMU MP1 was demonstrated in vitro and in vivo. RESULTS: Abundant polyunsaturated fatty acids (PUFAs) in OCM/AS suppressed RhoA-GTPase activities, which, in turn, downregulated nuclear YAP1 in MФs, leading to increased protumoral TAM polarization accompanied by elevated OXPHOS metabolism. Abolishment of YAP1 in MФs further confirmed that a higher M2/M1 ratio of TAM polarization could alleviate CD8+ T cell infiltration and cytotoxicity in vivo. Consistently, the loss of YAP1 has been observed in EOC metastatic tissues, suggesting its clinical relevance. On the contrary, restoration of YAP1 expression by pharmaceutical inhibition of MST1/2 induced conversion of M2-to-M1-like polarized MФs, elevating the infiltration of CD8+ T cells and attenuating tumor growth. CONCLUSION: This study revealed that PUFAs-enriched OCM/AS of EOC promotes M2-like TAM polarization through RhoA-YAP1 inhibition, where YAP1 downregulation is required for accelerating protumoral M2-like TAM polarization, thereby causing immunosuppression and enhancing tumor progression. Conversion of M2-to-M1-like polarized MФs through Yap1 activation inhibits tumor progression and contributes to developing potential TAMs-targeted immunotherapies in combating EOC peritoneal metastases.

17.
Adv Sci (Weinh) ; 11(12): e2306571, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38235606

RESUMO

Most patients with inflammatory bowel disease (IBD) develop anemia, which is attributed to the dysregulation of iron metabolism. Reciprocally, impaired iron homeostasis also aggravates inflammation. How this iron-mediated, pathogenic anemia-inflammation crosstalk is regulated in the gut remains elusive. Herein, it is for the first time revealed that anemic IBD patients exhibit impaired production of short-chain fatty acids (SCFAs), particularly butyrate. Butyrate supplementation restores iron metabolism in multiple anemia models. Mechanistically, butyrate upregulates ferroportin (FPN) expression in macrophages by reducing the enrichment of histone deacetylase (HDAC) at the Slc40a1 promoter, thereby facilitating iron export. By preventing iron sequestration, butyrate not only mitigates colitis-induced anemia but also reduces TNF-α production in macrophages. Consistently, macrophage-conditional FPN knockout mice exhibit more severe anemia and inflammation. Finally, it is revealed that macrophage iron overload impairs the therapeutic effectiveness of anti-TNF-α antibodies in colitis, which can be reversed by butyrate supplementation. Hence, this study uncovers the pivotal role of butyrate in preventing the pathogenic circuit between anemia and inflammation.


Assuntos
Anemia , Colite , Doenças Inflamatórias Intestinais , Humanos , Camundongos , Animais , Ferro/metabolismo , Butiratos/metabolismo , Butiratos/farmacologia , Inibidores do Fator de Necrose Tumoral/metabolismo , Inflamação/metabolismo , Anemia/metabolismo , Macrófagos/metabolismo , Camundongos Knockout
18.
Tumour Biol ; 34(4): 2225-31, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23636797

RESUMO

Previous studies suggest that genetic factors play important roles in the development of colorectal cancer. CYP2E1 T7632A and 9-bp insertion polymorphisms may influence the risk of colorectal cancer, but published results are conflicting. We therefore conducted a meta-analysis comprising 9 case-control studies with 4,592 cases and 5,918 controls. Odds ratios (ORs) with 95 % confidence interval (95 % CI) were used to assess the strength of the associations of CYP2E1 T7632A and 9-bp insertion polymorphisms with colorectal cancer. For CYP2E1 T7632A polymorphism, meta-analysis showed that there was no significant association between the CYP2E1 T7632A polymorphism and colorectal cancer risk under all contrast models (A vs. T: OR = 1.06, 95 % CI 0.88-1.29, P = 0.528; AA vs. TT: OR = 0.85, 95 % CI 0.61-1.19, P = 0.351; AA/TA vs. TT: OR = 1.08, 95 % CI 0.87-1.34, P = 0.484; and AA vs. TT/TA: OR = 0.87, 95 % CI 0.62-1.21, P = 0.395). For CYP2E1 96-bp insertion polymorphism, meta-analysis showed that there was a significant association between the CYP2E1 96-bp insertion polymorphism and colorectal cancer risk under the allele contrast model and the dominant contrast model (for the allele contrast model: OR = 1.20, 95 % CI 1.06-1.36, P = 0.005; for the dominant contrast model: OR = 1.25, 95 % CI 1.07-1.45, P = 0.005). Subgroup analysis by race suggested that there was an obvious association between the CYP2E1 96-bp insertion polymorphism and colorectal cancer risk in Asians under the codominant contrast model. In conclusion, our meta-analysis demonstrates that there is a significant association between the CYP2E1 96-bp insertion polymorphism and colorectal cancer risk, and CYP2E1 9-bp insertion polymorphism is a risk factor for developing colorectal cancer.


Assuntos
Neoplasias Colorretais/genética , Citocromo P-450 CYP2E1/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Mutagênese Insercional , Polimorfismo Genético , Risco
19.
Oncol Lett ; 25(2): 63, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36644148

RESUMO

Colorectal cancer (CRC) has high morbidity and mortality, particularly if diagnosed at an advanced stage. Although there have been several studies on CRC, few have investigated the relationship between oncosis and CRC. Thus, the purpose of the present study was to identify oncosis-related long noncoding RNAs (lncRNAs) and to establish a clinical prognostic model. Original data were acquired from The Cancer Genome Atlas database and PubMed. Differentially expressed oncosis-related lncRNAs (DEorlncRNAs) were identified and were subsequently formed into pairs. Next, a series of tests and analyses, including both univariate and multivariate analyses, as well as Lasso and Cox regression analyses, were performed to establish a receiver operating characteristic curve. A cut-off point was subsequently used to divide the samples into groups labelled as high- or low-risk. Thus, a model was established and evaluated in several dimensions. Six pairs of DEorlncRNAs associated with prognosis according to the algorithm were screened out and the CRC cases were divided into high- and low-risk groups. Significant differences between patients in the different risk groups were observed for several traits, including survival outcomes, clinical pathology characteristics, immune cell infiltration status and drug sensitivity. In addition, PCR and flow cytometry were performed to further verify the model. In summary, a new risk model algorithm based on six pairs of DEorlncRNAs in CRC, which does not require specific data regarding the level of gene expression, was established and validated. This algorithm may be used to predict patient prognosis, immune cell infiltration and drug sensitivity.

20.
Bioact Mater ; 28: 420-431, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37519924

RESUMO

Full-thickness skin wounds are have continued to be reconstructive challenges in dermal and skin appendage regeneration, and skin substitutes are promising tools for addressing these reconstructive procedures. Herein, the one-step fabrication of a cell sheet integrated with a biomimetic hydrogel as a tissue engineered skin for skin wound healing generated in one step is introduced. Briefly, cell sheets with rich extracellular matrix, high cell density, and good cell connections were integrated with biomimetic hydrogel to fabricate gel + human skin fibroblasts (HSFs) sheets and gel + human umbilical vein endothelial cells (HUVECs) sheets in one step for assembly as a cell sheet-laden hydrogel (CSH). The designed biomimetic hydrogel formed with UV crosslinking and ionic crosslinking exhibited unique properties due to the photo-generated aldehyde groups, which were suitable for integrating into the cell sheet, and ionic crosslinking reduced the adhesive force toward the substrate. These properties allowed the gel + cell sheet film to be easily released from the substrate. The cells in the harvested cell sheet maintained excellent viability, proliferation, and definite migration abilities inside the hydrogel. Moreover, the CSH was implanted into a full-thickness skin defects to construct a required dermal matrix and cell microenvironment. The wound closure rate reached 60.00 ± 6.26% on the 2nd day, accelerating mature granulation and dermis formation with skin appendages after 14 days. This project can provide distinct guidance and strategies for the complete repair and regeneration of full-thickness skin defects, and provides a material with great potential for tissue regeneration in clinical applications.

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