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1.
Hum Reprod ; 39(3): 516-525, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38195766

RESUMO

STUDY QUESTION: Does fluorescence lifetime imaging microscopy (FLIM)-based metabolic imaging assessment of human blastocysts prior to frozen transfer correlate with pregnancy outcomes? SUMMARY ANSWER: FLIM failed to distinguish consistent patterns in mitochondrial metabolism between blastocysts leading to pregnancy compared to those that did not. WHAT IS KNOWN ALREADY: FLIM measurements provide quantitative information on NAD(P)H and flavin adenine dinucleotide (FAD+) concentrations. The metabolism of embryos has long been linked to their viability, suggesting the potential utility of metabolic measurements to aid in selection. STUDY DESIGN, SIZE, DURATION: This was a pilot trial enrolling 121 IVF couples who consented to have their frozen blastocyst measured using non-invasive metabolic imaging. After being warmed, 105 couples' good-quality blastocysts underwent a 6-min scan in a controlled temperature and gas environment. FLIM-assessed blastocysts were then transferred without any intervention in management. PARTICIPANTS/MATERIALS, SETTING, METHODS: Eight metabolic parameters were obtained from each blastocyst (4 for NAD(P)H and 4 for FAD): short and long fluorescence lifetime, fluorescence intensity, and fraction of the molecule engaged with enzyme. The redox ratio (intensity of NAD(P)H)/(intensity of FAD) was also calculated. FLIM data were combined with known metadata and analyzed to quantify the ability of metabolic imaging to differentiate embryos that resulted in pregnancy from embryos that did not. De-identified discarded aneuploid human embryos (n = 158) were also measured to quantify correlations with ploidy status and other factors. Statistical comparisons were performed using logistic regression and receiver operating characteristic (ROC) curves with 5-fold cross-validation averaged over 100 repeats with random sampling. AUC values were used to quantify the ability to distinguish between classes. MAIN RESULTS AND THE ROLE OF CHANCE: No metabolic imaging parameters showed significant differences between good-quality blastocysts resulting in pregnancy versus those that did not. A logistic regression using metabolic data and metadata produced an ROC AUC of 0.58. In contrast, robust AUCs were obtained when classifying other factors such as comparison of Day 5 (n = 64) versus Day 6 (n = 41) blastocysts (AUC = 0.78), inner cell mass versus trophectoderm (n = 105: AUC = 0.88) and aneuploid (n = 158) versus euploid and positive pregnancy embryos (n = 108) (AUC = 0.82). LIMITATIONS, REASONS FOR CAUTION: The study protocol did not select which embryo to transfer and the cohort of 105 included blastocysts were all high quality. The study was also limited in number of participants and study sites. Increased power and performing the trial in more sites may have provided a stronger conclusion regarding the merits of the use of FLIM clinically. WIDER IMPLICATIONS OF THE FINDINGS: FLIM failed to distinguish consistent patterns in mitochondrial metabolism between good-quality blastocysts leading to pregnancy compared to those that did not. Blastocyst ploidy status was, however, highly distinguishable. In addition, embryo regions and embryo day were consistently revealed by FLIM. While metabolic imaging detects mitochondrial metabolic features in human blastocysts, this pilot trial indicates it does not have the potential to serve as an effective embryo viability detection tool. This may be because mitochondrial metabolism plays an alternative role post-implantation. STUDY FUNDING/COMPETING INTEREST(S): This study was sponsored by Optiva Fertility, Inc. Boston IVF contributed to the clinical site and services. Becker Hickl, GmbH, provided the FLIM system on loan. T.S. was the founder and held stock in Optiva Fertility, Inc., and D.S. and E.S. had options with Optiva Fertility, Inc., during this study. TRIAL REGISTRATION NUMBER: The study was approved by WCG Connexus IRB (Study Number 1298156).


Assuntos
Flavina-Adenina Dinucleotídeo , NAD , Feminino , Gravidez , Humanos , Projetos Piloto , Ploidias , Aneuploidia
2.
Cancers (Basel) ; 12(8)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722082

RESUMO

(1) Background: The relatively poor expert restaging accuracy of MRI in rectal cancer after neoadjuvant chemoradiation may be due to the difficulties in visual assessment of residual tumor on post-treatment MRI. In order to capture underlying tissue alterations and morphologic changes in rectal structures occurring due to the treatment, we hypothesized that radiomics texture and shape descriptors of the rectal environment (e.g., wall, lumen) on post-chemoradiation T2-weighted (T2w) MRI may be associated with tumor regression after neoadjuvant chemoradiation therapy (nCRT). (2) Methods: A total of 94 rectal cancer patients were retrospectively identified from three collaborating institutions, for whom a 1.5 or 3T T2w MRI was available after nCRT and prior to surgical resection. The rectal wall and the lumen were annotated by an expert radiologist on all MRIs, based on which 191 texture descriptors and 198 shape descriptors were extracted for each patient. (3) Results: Top-ranked features associated with pathologic tumor-stage regression were identified via cross-validation on a discovery set (n = 52, 1 institution) and evaluated via discriminant analysis in hold-out validation (n = 42, 2 institutions). The best performing features for distinguishing low (ypT0-2) and high (ypT3-4) pathologic tumor stages after nCRT comprised directional gradient texture expression and morphologic shape differences in the entire rectal wall and lumen. Not only were these radiomic features found to be resilient to variations in magnetic field strength and expert segmentations, a quadratic discriminant model combining them yielded consistent performance across multiple institutions (hold-out AUC of 0.73). (4) Conclusions: Radiomic texture and shape descriptors of the rectal wall from post-treatment T2w MRIs may be associated with low and high pathologic tumor stage after neoadjuvant chemoradiation therapy and generalized across variations between scanners and institutions.

3.
Inflamm Bowel Dis ; 23(8): 1328-1337, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28594651

RESUMO

BACKGROUND: As mechanisms of neoplasia in patients with ulcerative colitis (UC) remain poorly understood, we sought to identify pathways of carcinogenesis in this high-risk population. METHODS: MicroRNA (miRNA) and mRNA expression was examined in nondysplastic rectosigmoid mucosa from UC patients with (n = 19) or without remote colon neoplasia (n = 23). We developed a method to identify miRNA-regulated pathways based on differentially expressed miRNAs and their putative mRNAs targets in the same samples. One key pathway identified in the analysis, miR-4728-3p regulation of focal adhesion signaling was further evaluated in vitro and through examination of expression in UC-cancers. RESULTS: There were 101 significantly up-regulated and 98 down-regulated miRNAs (adjusted P < 0.05) in the rectal mucosa of UC patients harboring proximal neoplasia. Bioinformatic analysis identified miR-4728-3p as a regulator of 3 proteins involved in focal adhesion signaling, CAV1, THBS2, and COL1A2. Real-time PCR validated down-regulation of miR-4728-3p in nondysplastic tissue remote from UC-neoplasia and in UC-associated colon cancers. miR-4728-3p transfection into colon cancer cells down-regulated expression levels and decreased luciferase activities in cells expressing a wild type 3' untranslated region compared with a mutant 3' untranslated region for all 3 genes. Exogenous transfected miR-4728-3p also delayed wound healing and decreased formation of focal adhesion complexes. CONCLUSIONS: Patients with long-standing UC who harbor neoplasia can be identified based on miRNA and mRNA profiles in nondysplastic tissue. Using a method to analyze miRNA and mRNA expression from the same tissues, we identified that miR-4728-3p is likely an important tumor suppressor in UC-associated colon carcinogenesis.


Assuntos
Caveolina 1/metabolismo , Colite Ulcerativa/complicações , Colágeno Tipo I/metabolismo , Neoplasias Colorretais/patologia , Adesões Focais/genética , MicroRNAs/genética , Trombospondinas/metabolismo , Adulto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Caveolina 1/genética , Colágeno Tipo I/genética , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , Feminino , Seguimentos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais , Trombospondinas/genética
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