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1.
Theranostics ; 10(14): 6095-6112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32483441

RESUMO

Background and Aims: Cancer stem cells (CSCs) have been shown to be responsible for the tumor initiation, metastasis, and therapeutic resistance of colorectal cancer (CRC). Recent studies have also indicated the importance of CSCs in escaping immune surveillance. However, the coordinated epigenetic control of the stem cell signature and the key molecule(s) involved in immunosurveillance of colorectal CSCs (CRCSCs) are unclear. Here, we investigated the role of a histone modifier, AT-rich interaction domain-containing protein 3B (ARID3B), in CRC. Methods: CRC patient-derived xenografts (PDXs) with knockout of ARID3B induced by CRISPR/Cas9 in vivo were used. Molecular/cellular biology assays were performed. Clinical data obtained from The Cancer Genome Atlas, as well as from our cohort (Taipei Veterans General Hospital), were analyzed. Results: ARID3B was crucial for the growth of CRC, and ARID3B promoted the stem-like features of CRC. Mechanistically, ARID3B activated Notch target genes, intestinal stem cell (ISC) genes, and programmed death-ligand 1 (PD-L1) through the recruitment of lysine-specific demethylase 4C (KDM4C) to modulate the chromatin configuration for transcriptional activation. Clinical sample analyses showed that the coexpression of ARID3B and the Notch target HES1 correlated with a worse outcome and that ARID3B and PD-L1 were highly expressed in the consensus molecular subtype 4 of CRC. Pharmacological inhibition of KDM4 activity reversed the ARID3B-induced signature. Conclusion: We reveal a noncanonical Notch pathway for activating Notch target genes, ISC genes, and PD-L1 in CRC. This finding explains the immune escape of CRCSCs and indicates a potential group that may benefit from immune checkpoint inhibitors. Epigenetic drugs for reversing stem-like features of CRC should also be investigated.

2.
Theranostics ; 10(15): 6695-6714, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32550898

RESUMO

Background: Head and neck cancer (HNC) is a major cause of morbidity and mortality and has a poor treatment outcome. Irinotecan, a topoisomerase-I inhibitor, induces cell death by decreasing the religation of double-strand DNA. However, epithelial-mesenchymal transition (EMT), therapy resistance, and systemic toxicity caused by available antineoplastic agents hinder the efficacy and safety of HNC treatment. Chemotherapy combined with gene therapy shows potential application in circumventing therapy resistance and EMT. miR-200 exerts a remarkable suppressing effect on EMT-associated genes. Herein, liposomes and solid lipid nanoparticles (SLNs) modified with a pH-sensitive, self-destructive polyethylene glycol (PEG) shell and different peptides were designed as irinotecan and miR-200 nanovectors to enhance tumor-specific accumulation. These peptides included one ligand targeting the angiogenic tumor neovasculature, one mitochondrion-directed apoptosis-inducing peptide, and one cell-penetrating peptide (CPP) with high potency and selectivity toward cancer cells. Methods: Physicochemical characterization, cytotoxicity analysis, cellular uptake, regulation mechanisms, and in vivo studies on miR-200- and irinotecan-incorporated nanoparticles were performed to identify the potential antitumor efficacy and biosafety issues involved in HNC treatment and to elucidate the underlying signaling pathways. Results: We found that the cleavable PEG layer responded to low extracellular pH, and that the CPP and targeting peptides were exposed to improve the uptake and release of miR-200 and irinotecan into HNC human tongue squamous carcinoma (SAS) cells. The apoptosis of SAS cells treated with the combinatorial therapy was significantly induced by regulating various pathways, such as the Wnt/ß-catenin, MDR, and EMT pathways. The therapeutic efficacy and safety of the proposed co-treatment outperformed the commercially available Onivyde and other formulations used in a SAS tumor-bearing mouse model in this study. Conclusion: Chemotherapy and gene therapy co-treatment involving pH-sensitive and targeting peptide-modified nanoparticles may be an innovative strategy for HNC treatment.

3.
Cells ; 9(3)2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143517

RESUMO

Epithelial-mesenchymal transition (EMT) has been well recognized for its essential role in cancer progression as well as normal tissue development. In cancer cells, activation of EMT permits the cells to acquire migratory and invasive abilities and stem-like properties. However, simple categorization of cancer cells into epithelial and mesenchymal phenotypes misleads the understanding of the complicated metastatic process, and contradictory results from different studies also indicate the limitation of application of EMT theory in cancer metastasis. Nowadays, growing evidence suggests the existence of an intermediate status between epithelial and mesenchymal phenotypes, i.e., the "hybrid epithelial-mesenchymal (hybrid E/M)" state, provides a possible explanation for those conflicting results. Appearance of hybrid E/M phenotype offers a more plastic status for cancer cells to adapt the stressful environment for proceeding metastasis. In this article, we review the biological importance of the dynamic changes between the epithelial and the mesenchymal states. The regulatory mechanisms encompassing the translational, post-translational, and epigenetic control for this complex and plastic status are also discussed.

4.
Hematol Oncol ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32011024

RESUMO

BCR-ABL mutations are associated with resistance to tyrosine kinase inhibitors (TKIs) in Philadelphia chromosome-positive leukaemia. The emergence of these mutations in the era of second-generation TKIs, such as dasatinib and nilotinib, remains an evolving field. We conducted a retrospective study to quantitatively characterize the BCR-ABL transcript and mutation status during treatment with first-generation and second-generation TKI therapies. BCR-ABL mutations were detected by direct sequencing for patients with Philadelphia chromosome-positive leukaemia receiving TKI therapies. The efficacy of TKI therapy was quantitatively assessed by calculating the log reduction of BCR-ABL transcripts, which was measured using real-time quantitative polymerase chain reaction. Fisher's exact test was performed to analyse the associations of log reduction <3 and mutation status. We found 35 patients harbouring 55 mutations of 43 different types, of which 30% occurred in patients receiving imatinib, 27% in nilotinib, and 43% in dasatinib. We found a novel germline mutation, N336 N (AAC➔AAT), and two novel frameshift mutations, Asn358Thr fs*14 and Gly251Ala fs*16. T315I was the most common missense mutation, followed by V299L and F317L. Intron 8 35-bp insertion was the most frequent frameshift mutation. Both missense and multiple BCR-ABL mutations were significantly associated with worse molecular response compared with the molecular response of patients without mutation. Missense mutations, rather than frameshift, were associated with less log reduction, while the T315I, F317L, and T315A mutations were significantly correlated with poor log reduction. Collectively, amino acid substitutions at T315I, F317L, and T315A accounted for the majority of missense mutations and the loss of major molecular response. Mutation analysis is essential for patients receiving TKI therapy who exhibit an unfavourable response. The present study provided a landscape of BCR-ABL mutations in the era of second-generation TKIs.

5.
J Exp Clin Cancer Res ; 39(1): 10, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931847

RESUMO

In the original publication of this article [1], labelling within Fig. 7a was incorrect. The updated figure is shown below, with 'DMT1' now corrected to read 'DNMT1'.

6.
Oral Oncol ; 102: 104526, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31978755

RESUMO

OBJECTIVES: Given a lack of universally-accepted standard-of-care treatment for patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC), study objectives were to assess treatment utilization and survival outcomes for R/M HNSCC in the real-world setting. MATERIALS AND METHODS: A multi-site retrospective chart review was conducted in Europe (Germany, United Kingdom, Italy, Spain), Asia Pacific (Australia, South Korea, Taiwan), and Latin/North America (Brazil and Canada) to identify patients who initiated first-line systemic therapy for R/M HNSCC between January 2011 and December 2013. Patients were followed through December 2015 to collect clinical characteristics, treatment and survival data. RESULTS: Among 733 R/M HNSCC patients across 71 sites, median age was 60 years (inter-quartile range 54-67), 84% male, and 70% Eastern Cooperative Oncology Group performance status 0-1; 32% had oral cavity and 30% oropharyngeal cancers. The most common first-line regimen across all countries consisted of platinum-based combinations (73%), including platinum + 5-fluorouracil (5-FU) (26%), cetuximab + platinum ± 5-FU (22%), or taxane + platinum ± 5-FU (16%). However, use of different platinum-based combinations varied substantially; administration of cetuximab + platinum ± 5-FU was frequent in Italy (81%), Germany (46%) and Spain (38%), whereas use in other countries was limited. Median follow-up was 22.6 months (95% confidence interval [CI]: 21.5-24.6 months). Median real-world overall survival was only 8.0 months (95% CI: 7.0-8.0), with one-year survival reaching only 30.9% (95% CI: 27.5-34.3). CONCLUSION: Systemic therapies used in clinical practice for patients with R/M HNSCC vary substantially across countries. Prognosis remains poor in this patient population, highlighting the need for newer, more efficacious treatments.

7.
Biochem Biophys Res Commun ; 522(4): 1009-1014, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31813546

RESUMO

Hypoxia-inducible factor-1α (HIF-1α) induces cancer metastasis. We previously demonstrated that HIF-1α-induced membrane-type 4 matrix metalloproteinase (MT4-MMP) is involved in hypoxia-mediated metastasis in head and neck squamous cell carcinoma (HNSCC). However, the functions and detailed mechanisms of MT4-MMP in cancer metastasis are not well understood. In this study, we investigated whether MT4-MMP regulates invadopodia formation or individual cell movement-both critical to cancer migration and invasion-in three-dimensional (3D) environments. By expressing MT4-MMP in the HNSCC cell line FaDu, we demonstrated that MT4-MMP increases invadopodia formation and gelatin degradation. Furthermore, the amoeboid-like cell movement on collagen gel was increased by MT4-MMP expression in FaDu cells. Mechanistically, MT4-MMP may induce invadopodia formation by binding with Tks5 and PDGFRα to result in Src activation and promote amoeboid-like movement by stimulating the small GTPases Rho and Cdc42. Altogether, our data indicate that MT4-MMP induces two crucial mechanisms of cancer dissemination, invadopodia formation and amoeboid movement, and elucidate the prometastatic role of MT4-MMP in hypoxia-mediated cancer metastasis.

8.
J Exp Clin Cancer Res ; 38(1): 474, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31771617

RESUMO

BACKGROUND: The inflammatory cytokine interleukin-6 (IL-6) is critical for the expression of octamer-binding transcription factor 4 (OCT4), which is highly associated with early tumor recurrence and poor prognosis of hepatocellular carcinomas (HCC). DNA methyltransferase (DNMT) family is closely linked with OCT4 expression and drug resistance. However, the underlying mechanism regarding the interplay between DNMTs and IL-6-induced OCT4 expression and the sorafenib resistance of HCC remains largely unclear. METHODS: HCC tissue samples were used to examine the association between DNMTs/OCT4 expression levels and clinical prognosis. Serum levels of IL-6 were detected using ELISA assays (n = 144). Gain- and loss-of-function experiments were performed in cell lines and mouse xenograft models to determine the underlying mechanism in vitro and in vivo. RESULTS: We demonstrate that levels of DNA methyltransferase 3 beta (DNMT3b) are significantly correlated with the OCT4 levels in HCC tissues (n = 144), and the OCT4 expression levels are positively associated with the serum IL-6 levels. Higher levels of IL-6, DNMT3b, or OCT4 predicted early HCC recurrence and poor prognosis. We show that IL-6/STAT3 activation increases DNMT3b/1 and OCT4 in HCC. Activated phospho-STAT3 (STAT-Y640F) significantly increased DNMT3b/OCT4, while dominant negative phospho-STAT3 (STAT-Y705F) was suppressive. Inhibiting DNMT3b with RNA interference or nanaomycin A (a selective DNMT3b inhibitor) effectively suppressed the IL-6 or STAT-Y640F-induced increase of DNMT3b-OCT4 and ALDH activity in vitro and in vivo. The fact that OCT4 regulates the DNMT1 expressions were further demonstrated either by OCT4 forced expression or DNMT1 silence. Additionally, the DNMT3b silencing reduced the OCT4 expression in sorafenib-resistant Hep3B cells with or without IL-6 treatment. Notably, targeting DNMT3b with nanaomycin A significantly increased the cell sensitivity to sorafenib, with a synergistic combination index (CI) in sorafenib-resistant Hep3B cells. CONCLUSIONS: The DNMT3b plays a critical role in the IL-6-mediated OCT4 expression and the drug sensitivity of sorafenib-resistant HCC. The p-STAT3 activation increases the DNMT3b/OCT4 which confers the tumor early recurrence and poor prognosis of HCC patients. Findings from this study highlight the significance of IL-6-DNMT3b-mediated OCT4 expressions in future therapeutic target for patients expressing cancer stemness-related properties or sorafenib resistance in HCC.

9.
Head Neck ; 41 Suppl 1: 46-56, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31573750

RESUMO

BACKGROUND: Recently, two anti-PD-1 immune checkpoint inhibitors, pembrolizumab and nivolumab, have been approved by the US Food and Drug Administration for patients who fail on platinum-based chemotherapy. However, overall response and progression-free survival are still limited, and multiple novel agents are under development to fulfill this unmet clinical need. METHODS: Publications between 1992 and 2019 regarding the immunological/biological mechanisms and early phase clinical trial outcomes of immunomodulatory agents for head and neck cancer were described in this review article. RESULTS: Eleven immunomodulatory agents for advanced head and neck, including small molecules, antibodies, and therapeutic vaccines were described. Treatment responses were noted in nearly all 11 agents, as monotherapy or combination therapy. CONCLUSIONS: Potentials of the novel immunomodulatory agents to improve treatment efficacy of head and neck cancer and to maintain tolerable safety profile have been disclosed.

10.
Clin Otolaryngol ; 44(6): 1087-1095, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31574203

RESUMO

OBJECTIVES: Perineural invasion (PNI) is a poor prognostic pathologic feature of oral squamous cell carcinoma (OSCC). The mechanisms of PNI remain poorly understood, and nerve-tumour interactions have been implicated for its pathogenesis. DESIGN AND SETTING: Systematic investigation of nerve-tumour interactions was performed using fresh human peripheral nerve. In vitro and in vivo models were used to determine the ability of human peripheral nerves to enhance OSCC migration/invasion. Retrospective cohort study was also carried out in one medical centre from 2001 to 2009. PARTICIPANTS: 314 T1-2 OSCC patients. MAIN OUTCOME MEASURES: In the transwell migration/invasion assay, the cells in five representative fields were counted. In the nerve implantation model, tumour size was estimated. PNI quantification by PNI focus number was carried out in the OSCC patients to correlate with cervical lymph node metastasis and oncologic outcomes. RESULTS: The transwell migration/invasion assay demonstrated that human peripheral nerves, compared with subcutaneous soft tissue, significantly enhanced the migration/invasion abilities of OSCC. Moreover, the enhanced migration was dose-dependent with increased length or number of peripheral nerve segments. The nerve implantation model showed that human peripheral nerve also enhanced OSCC growth in vivo. Finally, increased PNI focus number was found dose-dependently associated with increased cervical lymph node metastasis and decreased 5-year disease-specific survival rates. CONCLUSIONS: These results clearly indicated the presence of nerve-tumour interaction that involved paracrine influences leading to aggressiveness of OSCC. Further investigations are required to explore key cell types and molecules involved in nerve-tumour interactions for future therapeutic targeting of PNI in OSCC.

11.
Nanoscale ; 11(44): 21119-21127, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31538997

RESUMO

An immunomagnetic "nano-net" was designed and synthesized for specifically capturing rare cells of interest from mixtures. The nano-net, Ab@Lipo-MNP-GO, consists of conjugated antibody molecules on a lipid coated magnetic nanoparticle-graphene oxide sheet complex. The magnetism, chemical composition, and the morphology of the construct and its precursors were characterized by SQUID, FTIR, TGA, DLS and SEM, to confirm the feasibility of the synthetic steps and the resulting properties suitable for solution phase immuno-recognition for cell capture. When applied to capturing circulating tumor cells (CTCs) in oral, colon and lung cancer clinical patients' blood samples, the nano-net construct exhibited far superior ability whereas conventional immunomagnetic beads in some cases were unable to capture any CTCs, even by increasing the bead concentration. Confocal images showed that the nano-net wrapped around the CTCs while the immunomagnetic beads attached them with point contacts. A stable, patch-like multivalent matrix nano-net was demonstrated to tackle the shortcomings of single point contact of immunomagnetic beads to the target cell. This strategy is universal for any cell separation in complex fluids.


Assuntos
Anticorpos Antineoplásicos/química , Grafite/química , Separação Imunomagnética , Nanoestruturas/química , Células Neoplásicas Circulantes/imunologia , Feminino , Células HCT116 , Humanos , Masculino
12.
Sci Rep ; 9(1): 12913, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501464

RESUMO

The median overall survival (OS) of some head and neck malignancies, such as head and neck squamous cell carcinoma (HNSCC), with metastatic lesions was only 12 months. Whether aggressive pulmonary metastasectomy (PM) improves survival is controversial. Patients with primary head and neck malignancy undergoing PM were enrolled. Clinical outcomes were compared among different histological types. Whole-exome sequencing was used for matched pulmonary metastatic samples. The genes where genetic variants have been identified were sent for analysis by DAVID, IPA, and STRING. Forty-nine patients with primary head and neck malignancies were enrolled. Two-year postmetastasectomy survival (PMS) rates of adenoid cystic carcinoma, thyroid carcinoma, nasopharyngeal carcinoma, and HNSCC were 100%, 88.2%, 71.4%, and 59.2%, respectively (P = 0.024). In HNSCC, the time to distant metastasis was an independent predictive factor of the efficacy of PM. Several pathways, such as branched-chain amino acid (BCAA) consumption, were significantly associated with the progression of HNSCC [P < 0.001, fold enrichment (FE) = 5.45]. Moreover, metabolism-associated signaling pathways also seemed to be involved in cancer metastasis. Histological types and time to distant metastasis were important factors influencing the clinical outcomes of PM. For HNSCC, metabolic-associated signaling pathways were significantly associated with tumor progression and distant metastasis. Future validations are warranted.

13.
Int J Oncol ; 55(4): 938-948, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31485600

RESUMO

Liposarcoma (LPS) is one of the most frequently reported type of soft­tissue sarcoma (STS). Well­differentiated (WD) LPS and dedifferentiated (DD) LPS are the two most common subtypes. Chemotherapy has been considered to be ineffective in LPS, and novel treatment agents are thus necessary. In this study, we reanalyzed two published microarray data sets of LPS. By comparing the top 50 upregulated genes in DD LPS in both sets of data, we identified 12 overlapping genes. Of note, the top five gene sets enriched in DD LPS in both sets of data were involved in cell cycle regulation. Among the 12 overlapping genes, aurora kinase A (AURKA) is a well­known gene involved in cell cycle regulation; we thus further investigated this gene. AURKA was significantly upregulated in DD LPS, compared with WD LPS. Among 40 cases of DD LPS in GSE30929, patients with high AURKA expression in tumors had significantly worse distant recurrence­free survival than those with low expression. In an in vitro model, MLN8237, an AURKA inhibitor, could inhibit AURKA in LPS cell lines with a resultant G2/M arrest. MLN8237 was also reported to exert a cytotoxic effect by inducing apoptosis in LPS cell lines. Furthermore, except for cisplatin, MLN8237 had a significantly synergistic effect with chemotherapy agents against LPS. MLN8237 induced cellular senescence in LPS cell lines with increased expression of DcR2, a senescence biomarker, and upregulated expression of cytokines associated with the senescence­associated secretory phenotype, including interleukin (IL)­1α, IL­6 and IL­8. Our study identified AURKA as a potential biomarker for predicting poor prognosis in LPS. The findings of the present study suggested the potential of AURKA as a therapeutic target in LPS cell line models, while the novel combination of AURKA inhibitors and chemotherapy requires further investigation.


Assuntos
Aurora Quinase A/genética , Azepinas/farmacologia , Perfilação da Expressão Gênica/métodos , Lipossarcoma/genética , Pirimidinas/farmacologia , Aurora Quinase A/antagonistas & inibidores , Desdiferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Tratamento Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lipossarcoma/tratamento farmacológico , Análise de Sequência com Séries de Oligonucleotídeos , Regulação para Cima/efeitos dos fármacos
14.
J Mol Med (Berl) ; 97(9): 1345-1357, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31302714

RESUMO

Corneal endothelial cell (CEC) dysfunction causes corneal edema that may lead to blindness. In addition to corneal transplantation, simple descemetorhexis has been proposed to treat centrally located disease with adequate peripheral cell reserve, but promoting the centripetal migration of CECs is pivotal to this strategy. Here, we show that targeting non-muscle myosin II (NMII) activity by Y27632, a ROCK inhibitor, or blebbistatin, a selective NMII inhibitor, promotes directional migration of CECs and accelerates in vitro wound healing. The lamellipodial protrusion persistence is increased, and actin retrograde flow is decreased after NMII inhibition. Counteracting lamellipodial protrusion by actin-related protein 2/3 (ARP2/3) inhibitor abolishes this migration-promoting effect. Although both Y27632 and blebbistatin accelerate wound healing, cell junctional integrity and barrier function are better preserved after blebbistatin treatment, leading to more rapid corneal deturgescence in rabbit corneal endothelial wounding model. Our findings indicate that NMII is a promising therapeutic target in the treatment of CEC dysfunction. KEY MESSAGES: NMII inhibition promotes directional migration and wound healing of CECs in vitro. Lamellipodial protrusion persistence is increased after NMII inhibition. Selective NMII inhibitor preserves junctional integrity better than ROCK inhibitor. Selective NMII inhibitor accelerates corneal deturgescence after wounding in vivo.

15.
Int J Oncol ; 55(2): 536-546, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31268158

RESUMO

Gastrointestinal stromal tumors (GISTs) are gastrointestinal tract sarcomas that commonly contain a mutation in the tyrosine kinases, KIT and platelet­derived growth factor receptor A (PDGFRA). Imatinib, sunitinib and regorafenib are all effective tyrosine kinase inhibitors; however, acquired resistance is inevitable. The E26 variant 1 (ETV1) pathway has been found to be a key downstream effector of KIT and is therefore a reasonable therapeutic target for this disease. In this study, we explored the potential agents targeting ETV1 in GISTs by uploading an ETV1 knockout gene signature of GIST cell lines to the pattern­matching software 'Connectivity Map'. The activity and mechanisms of identified agents were examined using an in vitro model. Four drugs were identified: Suberanilohydroxamic acid and trichostatin [two histone deacetylase inhibitors (HDACIs)] and trifluoperazine and thioridazine (two phenothiazine­class drugs). Western blot analysis demonstrated that all four drugs had ETV1­downregulating effects. As HDACIs have been previously studied in GISTs, we focused on phenothiazine. Phenothiazine was found to exert cytotoxicity and to induce apoptosis and autophagy in GISTs. Treatment with phenothiazine had little effect on the KIT/AKT/mammalian target of rapamycin (mTOR) pathway, but instead upregulated extracellular­signal­regulated kinase (ERK) activity. A combination of phenothiazine and a MEK inhibitor had a synergistic cytotoxic effect on GISTs. Western blot analysis indicated that ELK1 and early growth response 1 (EGR1) were activated/upregulated following phenothiazine treatment, and the MEK inhibitor/phenothiazine combination downregulated the ERK/ELK1/EGR1 pathway, resulting in diminished autophagy, as well as enhanced apoptosis. On the whole, the findings of this study established phenothiazine as a novel class of therapeutic agents in GIST treatment and demonstrate that a combination of phenothiazine and MEK inhibitor has great potential for use in the treatment of GISTs.


Assuntos
Biomarcadores Tumorais/genética , Conectoma , Proteínas de Ligação a DNA/antagonistas & inibidores , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fenotiazinas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Antineoplásicos/farmacologia , Antiprotozoários/farmacologia , Apoptose , Proteínas de Ligação a DNA/genética , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Perfilação da Expressão Gênica , Humanos , Prognóstico , Transdução de Sinais , Fatores de Transcrição/genética
16.
Oncologist ; 24(12): 1534-1542, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31292272

RESUMO

BACKGROUND: The form of microsatellite instability (MSI) affecting tetranucleotide repeats known as elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) has emerged as a new potential biomarker in multiple cancers. In colorectal cancer (CRC), the correlation between EMAST and MSI mutations remain inconclusive. MATERIALS AND METHODS: We evaluated 1,505 patients with CRC using five EMAST markers (D20S82, D20S85, D8S321, D9S242, and MYCL1) and the Bethesda panel of MSI markers. Most commonly, mutations involved in CRCs were identified by MassArray Assay, and DNA repair genes were analyzed by next-generation sequencing. Clinical characteristics and prognostic relevance were correlated with EMAST and MSI. RESULTS: Tumors that were EMAST positive and MSI high (MSI-H) were detected in 159 (10.6%) and 154 (10.2%) of 1,505 patients with CRC. Patients were divided into four groups according to EMAST and MSI status (EMAST-positive and MSI-H, EMAST-positive and microsatellite-stable [MSS], EMAST-negative and MSI-H, and EMAST-negative and MSS). The EMAST-positive and MSI-H group was associated with female predominance, higher prevalence of proximal colon tumors, early stage tumors, poorly differentiated tumors, mucinous histology, and higher incidence of mutations in PI3KCA, BRAF, TGFBR, PTEN, and AKT1 compared with other groups. Furthermore, compared with only EMAST-positive tumors or only MSI-H tumors, tumors that were both EMAST-positive and MSI-H had a higher frequency of MLH1, MSH3, MSH6, PMS2, and EXO1 gene mutations. Finally, the presence of EMAST-positive and MSI-H tumors was a good prognostic indicator in CRC. CONCLUSION: High mutations in several DNA repair genes in EMAST-positive and MSI-H tumors suggest that this subtype of CRC might be more suitable for treatment with immune therapy. IMPLICATIONS FOR PRACTICE: Elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) is a unique molecular subtype of colorectal cancer (CRC). The current study demonstrated that the EMAST-positive and MSI-high (MSI-H) group was associated with female predominance, higher prevalence of proximal colon tumors, early stage tumors, poorly differentiated tumors, mucinous histology, and higher incidence of mutations in PI3KCA, BRAF, TGFBR, PTEN, and AKT1 compared with other groups. Most importantly, high mutations in DNA repair genes and MSI-related genes in EMAST-positive and MSI-H tumors suggest that this subtype of CRC might be more suitable for treatment with immune therapy compared with MSI-H tumors alone.

17.
Int J Cancer ; 145(8): 2209-2224, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30980673

RESUMO

The dynamic cell-cell communication is essential for tissue homeostasis in normal physiological circumstances and contributes to a diversified tumor microenvironment. Although exosomes are extracellular vesicles that actively participate in cell-cell interaction by shutting cellular components, impacts of tumor exosomes in the context of cancer stemness remain elusive. Here, we expand colorectal cancer stem cells (CRCSCs) as cancer spheroids and demonstrate that the ß-catenin/Tcf-4-activated RAB27B expression is required for the secretion of CRCSC exosomes. In an exosomal RNA sequencing analysis, a switch of exosomal RNA species from retrotransposons to microRNAs (miRNAs) is identified upon expanding CRCSCs. miRNA-146a-5p (miR-146a) is the major miRNA in CRCSC exosomes and exosomal miR-146a promotes stem-like properties and tumorigenicity by targeting Numb in recipient CRC cells. Among 53 CRC patients, those with abundant exosomal miR-146a expression in serum exhibits higher miR-146aHigh /NumbLow CRCSC traits, an increased number of tumor-filtrating CD66(+) neutrophils and a decreased number of tumor-infiltrating CD8(+) T cells. Our study elucidates a unique mechanism of tumor exosome-mediated stemness expansion.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Exossomos/genética , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Proteínas rab de Ligação ao GTP/genética , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Exossomos/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células HT29 , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Interferência de RNA , Microambiente Tumoral/genética , Proteínas rab de Ligação ao GTP/metabolismo
18.
Nat Cell Biol ; 21(5): 664, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30820041

RESUMO

In the version of Supplementary Fig. 6c originally published with this Article, the immunoprecipitation (IP) and immunoblotting (IB) tags in the top panel were mislabelled. In addition, in Supplementary Fig. 6e, the blot of the IP: Numb; IB: ß-Trcp panel for HCT15 was mistakenly duplicated for HCT116. The correct versions of these figures are shown below. An independent repeat of the experiments presented in Supplementary Fig. 6c and e, showing results that are consistent with those reported in the unprocessed blots, have been deposited in figshare ( 10.6084/m9.figshare.7570685 ).

19.
Nat Cell Biol ; 21(4): 533, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30833696

RESUMO

In the version of Supplementary Fig. 3c originally published with this Article, the authors mistakenly duplicated a blot from Supplementary Fig. 3b. The correct versions of these figures are shown below. In addition, two independent repeats of the experiments presented in Supplementary Figs. 3b and 3c, showing results consistent with those originally reported, have been deposited in Figshare ( 10.6084/m9.figshare.7545263 ).

20.
Nat Cell Biol ; 21(2): 251-262, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30664792

RESUMO

Epithelial-mesenchymal transition (EMT) is a pivotal mechanism for cancer dissemination. However, EMT-regulated individual cancer cell invasion is difficult to detect in clinical samples. Emerging evidence implies that EMT is correlated to collective cell migration and invasion with unknown mechanisms. We show that the EMT transcription factor Snail elicits collective migration in squamous cell carcinoma by inducing the expression of a tight junctional protein, claudin-11. Mechanistically, tyrosine-phosphorylated claudin-11 activates Src, which suppresses RhoA activity at intercellular junctions through p190RhoGAP, maintaining stable cell-cell contacts. In head and neck cancer patients, the Snail-claudin-11 axis prompts the formation of circulating tumour cell clusters, which correlate with tumour progression. Overexpression of snail correlates with increased claudin-11, and both are associated with a worse outcome. This finding extends the current understanding of EMT-mediated cellular migration via a non-individual type of movement to prompt cancer progression.


Assuntos
Movimento Celular/genética , Claudinas/genética , Neoplasias/genética , Fatores de Transcrição da Família Snail/genética , Animais , Células CACO-2 , Linhagem Celular Tumoral , Células Cultivadas , Claudinas/metabolismo , Transição Epitelial-Mesenquimal/genética , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Neoplasias/patologia , Fatores de Transcrição da Família Snail/metabolismo , Transplante Heterólogo , Células Tumorais Cultivadas
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