Publications

2018

Ou, Yangming, Lilla Zöllei, Xiao Da, Kallirroi Retzepi, Shawn Murphy, Elizabeth Gerstner, Bruce Rosen, Ellen Grant, Jayashree Kalpathy-Cramer, and Randy Gollub. 2018. “Field of View Normalization in Multi-Site Brain MRI”. Neuroinformatics 16 (3-4): 431-44. https://doi.org/10.1007/s12021-018-9359-z.
Multi-site brain MRI analysis is needed in big data neuroimaging studies, but challenging. The challenges lie in almost every analysis step including skull stripping. The diversities in multi-site brain MR images make it difficult to tune parameters specific to subjects or imaging protocols. Alternatively, using constant parameter settings often leads to inaccurate, inconsistent and even failed skull stripping results. One reason is that images scanned at different sites, under different scanners or protocols, and/or by different technicians often have very different fields of view (FOVs). Normalizing FOV is currently done manually or using ad hoc pre-processing steps, which do not always generalize well to multi-site diverse images. In this paper, we show that (a) a generic FOV normalization approach is possible in multi-site diverse images; we show experiments on images acquired from Philips, GE, Siemens scanners, from 1.0T, 1.5T, 3.0T field of strengths, and from subjects 0-90 years of ages; and (b) generic FOV normalization improves skull stripping accuracy and consistency for multiple skull stripping algorithms; we show this effect for 5 skull stripping algorithms including FSL's BET, AFNI's 3dSkullStrip, FreeSurfer's HWA, BrainSuite's BSE, and MASS. We have released our FOV normalization software at http://www.nitrc.org/projects/normalizefov .
Davatzikos, Christos, Saima Rathore, Spyridon Bakas, Sarthak Pati, Mark Bergman, Ratheesh Kalarot, Patmaa Sridharan, et al. (2018) 2018. “Cancer Imaging Phenomics Toolkit: Quantitative Imaging Analytics for Precision Diagnostics and Predictive Modeling of Clinical Outcome”. J Med Imaging (Bellingham) 5 (1): 011018. https://doi.org/10.1117/1.JMI.5.1.011018.
The growth of multiparametric imaging protocols has paved the way for quantitative imaging phenotypes that predict treatment response and clinical outcome, reflect underlying cancer molecular characteristics and spatiotemporal heterogeneity, and can guide personalized treatment planning. This growth has underlined the need for efficient quantitative analytics to derive high-dimensional imaging signatures of diagnostic and predictive value in this emerging era of integrated precision diagnostics. This paper presents cancer imaging phenomics toolkit (CaPTk), a new and dynamically growing software platform for analysis of radiographic images of cancer, currently focusing on brain, breast, and lung cancer. CaPTk leverages the value of quantitative imaging analytics along with machine learning to derive phenotypic imaging signatures, based on two-level functionality. First, image analysis algorithms are used to extract comprehensive panels of diverse and complementary features, such as multiparametric intensity histogram distributions, texture, shape, kinetics, connectomics, and spatial patterns. At the second level, these quantitative imaging signatures are fed into multivariate machine learning models to produce diagnostic, prognostic, and predictive biomarkers. Results from clinical studies in three areas are shown: (i) computational neuro-oncology of brain gliomas for precision diagnostics, prediction of outcome, and treatment planning; (ii) prediction of treatment response for breast and lung cancer, and (iii) risk assessment for breast cancer.
Ou, Yangming, Lilla Zöllei, Xiao Da, Kallirroi Retzepi, Shawn Murphy, Elizabeth Gerstner, Bruce Rosen, Ellen Grant, Jayashree Kalpathy-Cramer, and Randy Gollub. 2018. “Field of View Normalization in Multi-Site Brain MRI”. Neuroinformatics 16 (3-4): 431–444.

2017

Ou, Yangming, Lilla Zöllei, Kallirroi Retzepi, Victor Castro, Sara Bates, Steve Pieper, Katherine Andriole, Shawn Murphy, Randy Gollub, and Patricia Ellen Grant. 2017. “Using Clinically Acquired MRI to Construct Age-Specific ADC Atlases: Quantifying Spatiotemporal ADC Changes from Birth to 6-Year Old”. Hum Brain Mapp 38 (6): 3052-68. https://doi.org/10.1002/hbm.23573.
Diffusion imaging is critical for detecting acute brain injury. However, normal apparent diffusion coefficient (ADC) maps change rapidly in early childhood, making abnormality detection difficult. In this article, we explored clinical PACS and electronic healthcare records (EHR) to create age-specific ADC atlases for clinical radiology reference. Using the EHR and three rounds of multiexpert reviews, we found ADC maps from 201 children 0-6 years of age scanned between 2006 and 2013 who had brain MRIs with no reported abnormalities and normal clinical evaluations 2+ years later. These images were grouped in 10 age bins, densely sampling the first 1 year of life (5 bins, including neonates and 4 quarters) and representing the 1-6 year age range (an age bin per year). Unbiased group-wise registration was used to construct ADC atlases for 10 age bins. We used the atlases to quantify (a) cross-sectional normative ADC variations; (b) spatiotemporal heterogeneous ADC changes; and (c) spatiotemporal heterogeneous volumetric changes. The quantified age-specific whole-brain and region-wise ADC values were compared to those from age-matched individual subjects in our study and in multiple existing independent studies. The significance of this study is that we have shown that clinically acquired images can be used to construct normative age-specific atlases. These first of their kind age-specific normative ADC atlases quantitatively characterize changes of myelination-related water diffusion in the first 6 years of life. The quantified voxel-wise spatiotemporal ADC variations provide standard references to assist radiologists toward more objective interpretation of abnormalities in clinical images. Our atlases are available at https://www.nitrc.org/projects/mgh_adcatlases. Hum Brain Mapp 38:3052-3068, 2017. © 2017 Wiley Periodicals, Inc.
Zhou, Chengzhi, Tao Chen, Zhanhong Xie, Yinyin Qin, Yangming Ou, Jiexia Zhang, Shiyue Li, Rongchang Chen, and Nanshan Zhong. (2017) 2017. “RACK1 Forms a Complex With FGFR1 and PKM2, and Stimulates the Growth and Migration of Squamous Lung Cancer Cells”. Mol Carcinog 56 (11): 2391-99. https://doi.org/10.1002/mc.22663.
Phosphorylation of Pyruvate Kinase M2 (PKM2) on Tyr105 by fibroblast growth factor receptor 1 (FGFR1) has been shown to promote its nuclear localization as well as cell growth in lung cancer. Better understanding the regulation of this process would benefit the clinical treatment for lung cancer. Here, it has been found that the adaptor protein receptor for activated PKC kinase (RACK1) formed a complex with FGFR1 and PKM2, and activated the FGFR1/PKM2 signaling. Knocking down the expression of RACK1 impaired the phosphorylation on Tyr105 of PKM2 and inhibited the growth and migration of lung cancer cells, while over-expression of RACK1 in lung cancer cells led to the resistance to Erdafitinib. Moreover, knocking down the expression of RACK1 impaired the tumorigenesis of lung cancer driven by LKB loss and mutated Ras (KrasG12D). Taken together, our study demonstrated the pivotal roles of RACK1 in FGFR1/PKM2 signaling, suggesting FGFR1/RACK1/PKM2 might be a therapeutic target for lung cancer treatment.