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1.
Carcinogenesis ; 34(2): 454-63, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23125220

RESUMEN

Nasopharyngeal carcinoma (NPC) is a type of head and neck cancer with significantly high prevalence in Southern China. Unlike other head and neck cancers, mutations or deletions of tumor suppressor genes in NPC are not common. Recently, downregulation of tumor suppressor genes expression by microRNA (miRNA) is increasingly recognized as an important mechanism of nasopharyngeal tumorigenesis. In this study, we reported that microRNA-144 (miR-144) was frequently upregulated in NPC specimens and cell lines. Repression of miR-144 significantly decreased cell proliferation, clonogenicity, migration, invasion and tumor formation in nude mice, while restoring miR-144 in miR-144-attenuated NPC cells exhibited a strong tumorigenic role. Further, we found that miR-144 was inversely correlated with the tumor suppressor gene phosphatase and tensin homolog (PTEN) in NPC specimens and cell lines, and then we identified PTEN as a direct target of miR-144 in NPC cell lines. PTEN downregulation in miR-144-attenuated cells could increase cell growth, migration and invasion. Mechanistic investigations revealed that miR-144 suppressed the expression of PTEN to increase the expression of pAkt and cyclin D1 to promote G(1)-phase transition and decrease E-cadherin to promote migration and invasion. Taken together, we provide compelling evidence that miR-144 functions as an onco-miRNA in NPC, and its oncoeffects are mediated chiefly by repressing PTEN expression to activate the PI3K/Akt pathway.


Asunto(s)
Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias Nasofaríngeas/patología , Nasofaringe/metabolismo , Fosfohidrolasa PTEN/antagonistas & inhibidores , Adulto , Anciano , Animales , Apoptosis , Western Blotting , Carcinoma , Estudios de Casos y Controles , Adhesión Celular , Ciclo Celular , Femenino , Humanos , Técnicas para Inmunoenzimas , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/genética , Invasividad Neoplásica , Fosfohidrolasa PTEN/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
2.
Phys Med ; 114: 103150, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37757501

RESUMEN

PURPOSE: Venezia™ is an interstitial brachytherapy applicator for treating advanced cervical and vaginal vault recurrent cancer. However, there are limitations that lead to suboptimal target coverage. 3D printing introduction allows the redesign of Venezia™ for bulky and irregular-shaped tumors. METHODS: This study first describes three new designs included: 1) add-on needles template allowed for an extra layer of straight and oblique needles, 2) redesigned vaginal cap so straight and oblique needles can be used together and 3) redesigned central tube allowed vaginal vault interstitial needle insertion. Drawbacks to original Venezia™ and rationale for using these new designs were discussed. Dosimetric analysis by comparing the original Venezia™ with new design for 10 cases in Oncentra treatment planning system v4.5 (Elekta, Stockholm, Sweden) to observe the dose differences in gross tumor volume (GTV), high risk clinical target volume (HRCTV), intermediate clinical target volume (IRCTV) and organs at risk. RESULTS: For the dosimetric comparison, there were statistically significantly increased median minimal dose to 98% (D98%) of GTV, 90% (D90%) of HRCTV, and IRCTV for the new design with p-value of 0.008, 0.005 and 0.0018, respectively. Comparing the physical dose of D98% of GTV, D90% of HRCTV, and IRCTV when using the new design, it averagely increased by 11.7%, 8.0%, 19.4%, respectively per fraction. CONCLUSIONS: Dosimetric comparison revealed the new designs increased the dose to GTV, HRCTV and IRCTV and fulfilled the dose constraints of bladder, rectum and sigmoid. The 3D printed new design is biocompatible, inexpensive and can be patient specific.


Asunto(s)
Braquiterapia , Neoplasias Endometriales , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/patología , Cuello del Útero , Dosificación Radioterapéutica , Estudios de Factibilidad , Planificación de la Radioterapia Asistida por Computador
3.
JTO Clin Res Rep ; 4(5): 100499, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37223611

RESUMEN

Introduction: Lorlatinib is a potent, third-generation inhibitor of ALK. In the planned interim analysis of the ongoing, phase 3, randomized, global CROWN trial (NCT03052608), lorlatinib resulted in significantly longer progression-free survival than crizotinib in patients with previously untreated, advanced, ALK-positive NSCLC. Here, we present a subgroup analysis of Asian patients in the CROWN study. Methods: Patients received lorlatinib 100 mg once daily or crizotinib 250 mg twice daily. The primary end point was progression-free survival assessed by blinded independent central review. Objective response rate (ORR), intracranial ORR, safety, and select biomarkers were secondary end points. Results: At data cutoff (September 20, 2021), 120 patients were included in the Asian intention-to-treat subgroup (lorlatinib n = 59; crizotinib n = 61). At 36 months, 61% (95% confidence interval [CI]: 47-72) and 25% (95% CI: 12-41) of patients in the lorlatinib and crizotinib groups, respectively, were alive without disease progression (hazard ratio for disease progression by blinded independent central review or death: 0.40; 95% CI: 0.23-0.71). ORR was 78% (95% CI: 65-88) versus 57% (95% CI: 44-70) for patients treated with lorlatinib and crizotinib, respectively. In patients with measurable, nonmeasurable, or both measurable and nonmeasurable brain metastases at baseline, intracranial ORR was 73% (95% CI: 39-94) versus 20% (95% CI: 4-48) for patients treated with lorlatinib and crizotinib, respectively. The definition of nonmeasurable brain metastases is: a brain lesion less than 10 mm in MRI scan is defined as nonmeasurable brain metastasi based on RECIST criteria (Clinical trial evaluation criteria). Hypercholesterolemia, hypertriglyceridemia, and edema were the most frequently reported adverse events with lorlatinib. Conclusions: Lorlatinib efficacy and safety in the Asian subgroup of CROWN were consistent with those in the overall population.

4.
Int J Radiat Oncol Biol Phys ; 112(4): 1033-1044, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-34774997

RESUMEN

PURPOSE: To investigate a novel deep-learning network that synthesizes virtual contrast-enhanced T1-weighted (vceT1w) magnetic resonance images (MRI) from multimodality contrast-free MRI for patients with nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS: This article presents a retrospective analysis of multiparametric MRI, with and without contrast enhancement by gadolinium-based contrast agents (GBCAs), obtained from 64 biopsy-proven cases of NPC treated at Hong Kong Queen Elizabeth Hospital. A multimodality-guided synergistic neural network (MMgSN-Net) was developed to leverage complementary information between contrast-free T1-weighted and T2-weighted MRI for vceT1w MRI synthesis. Thirty-five patients were randomly selected for model training, whereas 29 patients were selected for model testing. The synthetic images generated from MMgSN-Net were quantitatively evaluated against real GBCA-enhanced T1-weighted MRI using a series of statistical evaluating metrics, which include mean absolute error (MAE), mean squared error (MSE), structural similarity index (SSIM), and peak signal-to-noise ratio (PSNR). Qualitative visual assessment between the real and synthetic MRI was also performed. Effectiveness of our MMgSN-Net was compared with 3 state-of-the-art deep-learning networks, including U-Net, CycleGAN, and Hi-Net, both quantitatively and qualitatively. Furthermore, a Turing test was performed by 7 board-certified radiation oncologists from 4 hospitals for assessing authenticity of the synthesized vceT1w MRI against the real GBCA-enhanced T1-weighted MRI. RESULTS: Results from the quantitative evaluations demonstrated that our MMgSN-Net outperformed U-Net, CycleGAN and Hi-Net, yielding the top-ranked scores in averaged MAE (44.50 ± 13.01), MSE (9193.22 ± 5405.00), SSIM (0.887 ± 0.042), and PSNR (33.17 ± 2.14). Furthermore, the mean accuracy of the 7 readers in the Turing tests was determined to be 49.43%, equivalent to random guessing (ie, 50%) in distinguishing between real GBCA-enhanced T1-weighted and synthetic vceT1w MRI. Qualitative evaluation indicated that MMgSN-Net gave the best approximation to the ground-truth images, particularly in visualization of tumor-to-muscle interface and the intratumor texture information. CONCLUSIONS: Our MMgSN-Net was capable of synthesizing highly realistic vceT1w MRI that outperformed the 3 comparable state-of-the-art networks.


Asunto(s)
Imagen por Resonancia Magnética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Medios de Contraste , Humanos , Imagen por Resonancia Magnética/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagen , Neoplasias Nasofaríngeas/diagnóstico por imagen , Redes Neurales de la Computación , Estudios Retrospectivos
5.
EBioMedicine ; 86: 104357, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36371985

RESUMEN

BACKGROUND: Epstein-Barr virus (EBV) latent infection is associated with genome-wide epigenomic changes in several malignancies, but its role in epigenetic dysregulation remains unclear in nasopharyngeal carcinoma (NPC). METHODS: To investigate EBV-associated epigenetic dysregulation, we performed a multi-omics study by integrating whole-genome bisulfite sequencing (WGBS), assay for transposase-accessible chromatin using sequencing (ATAC-Seq), whole-exome sequencing (WES), and single-cell RNA sequencing (scRNA-Seq) data. FINDINGS: In addition to the known global DNA hypermethylated subtype, we discovered a novel subtype with global hypomethylation in EBV + NPC. The consistent EBV-specific differentially methylated regions (EBV-DMRs) in the human genome were identified from both subtypes and associated with loss of CTCF binding (P < 2.2e-16). Importantly, CTCF is a master chromatin regulator and CTCF protein was reduced in 45% of NPC cases, especially in those with advanced NPC (Stage IV vs. others: 62% vs. 38%, P = 0.034). This result links EBV with chromatin changes. The ATAC-Seq data suggest regulatory epigenome reprogramming through chromatin accessibility changes in EBV + NPC with altered CTCF binding and the switch of transcription factor binding from differentiation-associated KLF/SP family to the innate and adaptive immunity-related NF-ĸB and IRF families. Detailed chromatin accessibility analysis identified a potential EBV target gene CD74, which mediated EBV-specific cell-cell communications in the tumor microenvironment (TME) and was strongly correlated with T cell exhaustion (r2 = 0.55). INTERPRETATION: Our study reveals the unexpected epigenetic heterogeneity, providing insights into NPC pathogenesis and highlighting the involvement of host factors in virus-associated epigenetic changes. EBV infection is associated with epigenome reprogramming and may promote immune evasion. FUNDING: This study was funded by the Hong Kong Research Grants Council grant (AoE/M-06/08) to MLL, General Research Fund (17103218 and 17102619) and seed funding for basic research (201611159158) to WD, and General Research Fund (17119618) to HC.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/genética , Herpesvirus Humano 4/genética , Epigenómica , Epigenoma , Cromatina , Neoplasias Nasofaríngeas/patología , Microambiente Tumoral/genética
6.
Osteoporos Sarcopenia ; 7(Suppl 1): S19-S27, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33997305

RESUMEN

OBJECTIVES: Sarcopenia is recognized to be a health problem which is as serious as obesity, but its relevance to mortality is unclear. We conducted a meta-analysis of cohort studies on lean mass and mortality in populations with different health conditions. METHODS: In this study, a systematic search of PubMed, Cochrane Library and Embase was performed for cohort studies published before Dec 20, 2017 which examined the relationship between lean mass and mortality. We included studies reporting lean mass measurement by dual-energy X-ray absorptiometry, bioimpedance analysis or computed tomography, as continuous (per standard deviation [SD] decrease) or binary variables (using sarcopenia cutoffs). We excluded studies which used muscle mass surrogates, anthropometric measurement of muscle, rate of change in muscle mass, and sarcopenia defined by composite criteria. The primary study outcome was all-cause mortality. Pooled hazard ratio estimates were calculated using a random effects model. RESULTS: A total of 9602 articles were identified from the systematic search, and 188 studies with 98 468 participants from 34 countries were included in the meta-analysis. Of the 68 studies included in the present meta-analysis, the pooled HR was 1.36 and 1.74 for every SD decrease in lean mass and in people with low lean mass (cutoffs), respectively. Significant associations were also observed in elderly and all disease subgroups, irrespective of the measurement modalities. CONCLUSIONS: Lower lean mass is robustly associated with increased mortality, regardless of health conditions and lean mass measurement modalities. This meta-analysis highlighted low lean mass as a key public health issue.

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