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1.
Langmuir ; 40(36): 19195-19208, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39192631

ABSTRACT

The process of spraying water and flavorings on dry tobacco is an important factor in the industrial environment and product quality. Tobacco as a complex porous fiber material, the interfacial transfer process of water is complex. In this study, machine learning and image recognition techniques were utilized to quickly obtain the structural parameters of the tobacco surface and construct a cellular structure model of the tobacco surface. In situ observation of the droplet impact spreading process was carried out using a high-speed camera to explore the droplet dissipation dynamics on different surfaces. And the competing processes of droplet wetting and evaporation under the influence of surface microstructure were determined by combining experimental studies and finite element simulation calculations. Based on the characteristics of tobacco pore size distribution, the infiltration under gas-liquid two-phase action was transformed into single-phase flow transfer under capillary force, and the continuous droplet infiltration process was simulated. A parallel artificial membrane permeability measurement method of bionic tobacco waxy layer was constructed for the screening of spray dosing copenetrant. This study brings new insights into the wetting of porous fibrous materials and is important for exploring the wetting process and additive development process influenced by the microstructure.

2.
Environ Res ; 263(Pt 1): 120055, 2024 Sep 23.
Article in English | MEDLINE | ID: mdl-39322059

ABSTRACT

BACKGROUND: Air pollution and outdoor light at night (LAN) have been reported to be related to type 2 diabetes (T2D). However, their interaction with risk of T2D remains uncertain. Therefore, our study aimed to explore the relationship between outdoor LAN, air pollution and incident T2D. METHODS: Our study included a cohort of 24,147 subjects recruited from 2015 to 2018 in Ningbo, China. Land use regression models were used to evaluate particulate matter with a diameter ≤2.5 µm (PM2.5), ≤10 µm (PM10) and nitrogen dioxide (NO2). Satellite images data with a spatial resolution of 500m was used to estimate outdoor LAN levels. T2D new cases were identified by medical records based on health information system. Cox proportional hazards models were used to estimate Hazard ratios (HRs) and 95% confidence intervals (CIs). Moreover, we investigated the multiplicative and additive interactions between air pollution and outdoor LAN. RESULTS: During 108,908 person-years of follow-up period, 1016 T2D incident cases were identified. The HRs (95% CIs) were 1.22 (1.15, 1.30) for outdoor LAN, 1.20 (1.00, 1.45) for PM2.5, 1.23 (1.11, 1.35) for PM10 and 1.19 (1.04, 1.37) for NO2 in every interquartile range increase, respectively. Furthermore, significant interactions were observed between outdoor LAN and NO2. CONCLUSIONS: Our findings indicated that air pollution and outdoor LAN were positively associated with T2D. Moreover, we observed an interaction between outdoor LAN and NO2 suggesting that stronger associations for outdoor LAN and T2D in areas with higher levels of NO2, and for NO2 and T2D in areas with higher levels of outdoor LAN.

3.
Gut ; 71(5): 938-949, 2022 05.
Article in English | MEDLINE | ID: mdl-34059508

ABSTRACT

OBJECTIVE: Enhancer aberrations are beginning to emerge as a key epigenetic feature of colorectal cancers (CRC), however, a comprehensive knowledge of chromatin state patterns in tumour progression, heterogeneity of these patterns and imparted therapeutic opportunities remain poorly described. DESIGN: We performed comprehensive epigenomic characterisation by mapping 222 chromatin profiles from 69 samples (33 colorectal adenocarcinomas, 4 adenomas, 21 matched normal tissues and 11 colon cancer cell lines) for six histone modification marks: H3K4me3 for Pol II-bound and CpG-rich promoters, H3K4me1 for poised enhancers, H3K27ac for enhancers and transcriptionally active promoters, H3K79me2 for transcribed regions, H3K27me3 for polycomb repressed regions and H3K9me3 for heterochromatin. RESULTS: We demonstrate that H3K27ac-marked active enhancer state could distinguish between different stages of CRC progression. By epigenomic editing, we present evidence that gains of tumour-specific enhancers for crucial oncogenes, such as ASCL2 and FZD10, was required for excessive proliferation. Consistently, combination of MEK plus bromodomain inhibition was found to have synergistic effects in CRC patient-derived xenograft models. Probing intertumour heterogeneity, we identified four distinct enhancer subtypes (EPIgenome-based Classification, EpiC), three of which correlate well with previously defined transcriptomic subtypes (consensus molecular subtypes, CMSs). Importantly, CMS2 can be divided into two EpiC subgroups with significant survival differences. Leveraging such correlation, we devised a combinatorial therapeutic strategy of enhancer-blocking bromodomain inhibitors with pathway-specific inhibitors (PARPi, EGFRi, TGFßi, mTORi and SRCi) for EpiC groups. CONCLUSION: Our data suggest that the dynamics of active enhancer underlies CRC progression and the patient-specific enhancer patterns can be leveraged for precision combination therapy.


Subject(s)
Chromatin , Colorectal Neoplasms , Basic Helix-Loop-Helix Transcription Factors , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Enhancer Elements, Genetic/genetics , Humans , Nuclear Proteins , Transcription Factors/genetics
4.
Anal Biochem ; 631: 114299, 2021 10 15.
Article in English | MEDLINE | ID: mdl-34391726

ABSTRACT

Antibiotics are widely used to treat bacterial infections during the process of vaccine production and storage resulting in antibiotic residues that can cause serious harm. A simple and sensitive method for residue analysis of 40 ß-lactam antibiotics was developed and validated for vaccines including inactivated enterovirus 71 vaccine (Vero cells), recombinant hepatitis B vaccine (Saccharomyces cerevisiae), and live attenuated varicella vaccine using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI- MS/MS). Samples were prepared with acetonitrile as the protein precipitant. LC separation was performed on a C18 column. These analytes were determined by LC-MS/MS operating multiple-reaction monitoring (MRM) scans in positive mode. The ranges for limits of detection (LOD) and quantification (LOQ) were as follows: 0.02-4 ng/dose (S/N ≥ 3) and 0.04-10 ng/dose in inactivated enterovirus 71 vaccine (Vero cells) and recombinant hepatitis B vaccine (Saccharomyces cerevisiae), 0.04-16 ng/dose and 0.2-20 ng/dose in live attenuated varicella vaccine. The ranges of recoveries of all antibiotics were 84.5%-108.2% in inactivated enterovirus 71 vaccine (Vero cells), 73%-108% in recombinant hepatitis B vaccine (Saccharomyces cerevisiae), and mostly 68.2%-107.8% in live attenuated varicella vaccine. This method simultaneously offers qualitative and quantitative analysis of multi-antibiotics in vaccines, which improves vaccine safety.


Subject(s)
Anti-Bacterial Agents/analysis , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Vaccines/analysis , beta-Lactams/analysis , Animals , Chickenpox Vaccine/analysis , Chlorocebus aethiops , Drug Contamination , Hepatitis B Vaccines/analysis , Limit of Detection , Reproducibility of Results , Saccharomyces cerevisiae , Vero Cells
5.
Ann Surg Oncol ; 24(13): 4051-4058, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28936799

ABSTRACT

BACKGROUND: The directed study of the functional proteome in colorectal cancer (CRC) has identified critical protein markers and signaling pathways; however, the prognostic relevance of many of these proteins remains unclear. METHODS: We determined the prognostic implications of the functional proteome in 263 CRC tumor samples from patients treated at MD Anderson Cancer Center (MDACC) and 462 patients from The Cancer Genome Atlas (TCGA) to identify patterns of protein expression that drive tumorigenesis. A total of 163 validated proteins were analyzed by reverse phase protein array (RPPA). Unsupervised hierarchical clustering of the tumor proteins from the MDACC cohort was performed, and clustering was validated using RPPA data from TCGA CRC. Cox regression was used to identify predictors of tumor recurrence. RESULTS: Clustering revealed dichotomization, with subtype A notable for a high epithelial-mesenchymal transition (EMT) protein signature, while subtype B was notable for high Akt/TSC/mTOR pathway components. Survival data were only available for the MDACC cohort and were used to evaluate prognostic relevance of these protein signatures. Group B demonstrated worse relapse-free survival (hazard ratio 2.11, 95% confidence interval 1.04-4.27, p = 0.039), although there was no difference in known genomic drivers between the two proteomic groups. Proteomic grouping and stage were significant predictors of recurrence on multivariate analysis. Eight proteins were found to be significant predictors of tumor recurrence on multivariate analysis: Collagen VI, FOXO3a, INPP4B, LcK, phospho-PEA15, phospho-PRAS40, Rad51, phospho-S6. CONCLUSION: CRC can be classified into distinct subtypes by proteomic features independent of common oncogenic driver mutations. Proteomic analysis has identified key biomarkers with prognostic importance, however these findings require further validation in an independent cohort.


Subject(s)
Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Colorectal Neoplasms/mortality , Mutation , Proteomics/methods , Cohort Studies , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Female , Follow-Up Studies , Gene Expression Regulation, Neoplastic , Humans , Male , Middle Aged , Prognosis , Survival Rate
6.
Int J Cancer ; 138(1): 195-205, 2016 Jan 01.
Article in English | MEDLINE | ID: mdl-26152787

ABSTRACT

Dysregulation of the Notch1 receptor has been shown to facilitate the development and progression of colorectal cancer (CRC) and has been identified as an independent predictor of disease progression and worse survival. Although mutations in the NOTCH1 receptor have not been described in CRC, we have previously discovered a NOTCH1 gene copy number gain in a portion of CRC tumor samples. Here, we demonstrated that a NOTCH1 gene copy number gain is significantly associated with worse survival and a high percentage of gene duplication in a cohort of patients with advanced CRC. In our CRC patient-derived tumor xenograft (PDTX) model, tumors harboring a NOTCH1 gain exhibited significant elevation of the Notch1 receptor, JAG1 ligand and cleaved Notch1 activity. In addition, a significant association was identified between a gain in NOTCH1 gene copy number and sensitivity to a Notch1-targeting antibody. These findings suggest that patients with metastatic CRC that harbor a gain in NOTCH1 gene copy number have worse survival and that targeting this patient population with a Notch1 antibody may yield improved outcomes.


Subject(s)
Colorectal Neoplasms/genetics , Colorectal Neoplasms/mortality , DNA Copy Number Variations , Gene Dosage , Receptor, Notch1/genetics , Animals , Antibodies, Monoclonal/pharmacology , Apoptosis/drug effects , Apoptosis/genetics , Biomarkers, Tumor , Calcium-Binding Proteins/metabolism , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Disease Models, Animal , Drug Resistance, Neoplasm/genetics , Female , Gene Duplication , Humans , Intercellular Signaling Peptides and Proteins/metabolism , Jagged-1 Protein , Male , Membrane Proteins/metabolism , Mice , Neoplasm Metastasis , Prognosis , Receptor, Notch1/antagonists & inhibitors , Receptor, Notch1/metabolism , Serrate-Jagged Proteins , Signal Transduction/drug effects , Xenograft Model Antitumor Assays
7.
Br J Cancer ; 114(12): 1352-61, 2016 06 14.
Article in English | MEDLINE | ID: mdl-27272216

ABSTRACT

BACKGROUND: High EREG and AREG expression, and left-sided primary tumours are associated with superior efficacy of anti-epidermal growth factor receptor (EGFR) therapy in metastatic colorectal cancer (CRC), but a unifying explanation of these findings is lacking. METHODS: RNA-seq, gene expression arrays, and DNA methylation profiling were completed on 179 CRC tumours. Results were validated using independent The Cancer Genome Atlas data sets. An independent cohort of 198 KRAS wild-type metastatic CRC tumours was tested for CpG island methylator phenotype (CIMP) status, and progression-free survival (PFS) with the first anti-EGFR regimen was retrospectively determined. RESULTS: EREG and AREG expression was highly inversely correlated with methylation and was inversely associated with right-sided primary tumour, BRAF mutation, and CIMP-high status. Treatment of CRC cell lines with hypomethylating agents decreased methylation and increased expression of EREG. Inferior PFS with anti-EGFR therapy was associated with CIMP-high status, BRAF mutation, NRAS mutation, and right-sided primary tumour on univariate analysis. Among known BRAF/NRAS wild-type tumours, inferior PFS remained associated with CIMP-high status (median PFS 5.6 vs 9.0 mo, P=0.023). CONCLUSIONS: EREG and AREG are strongly regulated by methylation, and their expression is associated with CIMP status and primary tumour site, which may explain the association of primary tumour site and EREG/AREG expression with anti-EGFR therapy efficacy.


Subject(s)
Amphiregulin/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , CpG Islands , DNA Methylation , Epiregulin/genetics , Amphiregulin/biosynthesis , Cohort Studies , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Epiregulin/biosynthesis , ErbB Receptors/antagonists & inhibitors , HCT116 Cells , Humans , Male , Phenotype , Promoter Regions, Genetic , Proto-Oncogene Proteins p21(ras)/biosynthesis , Proto-Oncogene Proteins p21(ras)/genetics
8.
Cancer ; 121(17): 2968-75, 2015 Sep 01.
Article in English | MEDLINE | ID: mdl-25975416

ABSTRACT

BACKGROUND: Obesity is strongly linked with chronic systemic inflammation, and each has been linked with disease progression and survival in patients with colorectal cancer (CRC). The authors investigated the joint prognostic effects of obesity and circulating cytokines in patients with metastatic CRC (mCRC), an understudied patient group. METHODS: In 242 chemotherapy-naive patients with mCRC, the authors measured a multiplex cytokine panel and abstracted clinicopathological features, height, and weight from medical records. Overall survival (OS) was calculated from the date of mCRC diagnosis until the date of death from any cause and evaluated by Kaplan-Meier analysis and multivariable Cox proportional hazards regression models. Cut points for cytokines were determined by restricted cubic spline regression. RESULTS: In multivariable models, elevated interleukin (IL)-8, IL-2 receptor alpha, and lactate dehydrogenase (LDH) emerged as significant predictors of poor OS (hazard ratio [HR] and 95% confidence interval [95% CI] for above vs below the (referent) knot point: 2.5 [95% CI, 1.7-3.7], 1.9 [95% CI, 1.3-2.7], and 2.2 [95% CI, 1.6-3.1], respectively; all P<.001). Obesity (body mass index ≥30 kg/m(2) ) was not found to be associated with OS, but appeared to modify the relationships observed with IL-8 and LDH, which were associated with a significant 4-fold and 5-fold risk of death, respectively, in obese patients compared with a 2-fold risk of death in nonobese patients (P for interaction of .06 and .04, respectively). Similar results emerged from joint effects analysis, in which obese patients with high IL-8 (or LDH) experienced the highest risk of death. CONCLUSIONS: Although obesity itself was not found to be independently associated with survival in patients with mCRC, the adverse prognostic significance of LDH and IL-8 was found to be enhanced in obese patients.


Subject(s)
Colorectal Neoplasms/pathology , Cytokines/blood , Obesity/blood , Colorectal Neoplasms/blood , Colorectal Neoplasms/mortality , Female , Humans , Inflammation/blood , Kaplan-Meier Estimate , Male , Middle Aged , Multivariate Analysis , Neoplasm Metastasis , Obesity/mortality , Obesity/pathology , Prognosis , Proportional Hazards Models
9.
Oncologist ; 20(2): 127-33, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25561511

ABSTRACT

BACKGROUND: Approximately 20% of patients with stage II colorectal cancer will experience a relapse. Current clinical-pathologic stratification factors do not allow clear identification of these high-risk patients. ColoPrint (Agendia, Amsterdam, The Netherlands, http://www.agendia.com) is a gene expression classifier that distinguishes patients with low or high risk of disease relapse. METHODS: ColoPrint was developed using whole-genome expression data and validated in several independent validation cohorts. Stage II patients from these studies were pooled (n = 416), and ColoPrint was compared with clinical risk factors described in the National Comprehensive Cancer Network (NCCN) 2013 Guidelines for Colon Cancer. Median follow-up was 81 months. Most patients (70%) did not receive adjuvant chemotherapy. Risk of relapse (ROR) was defined as survival until first event of recurrence or death from cancer. RESULTS: In the pooled stage II data set, ColoPrint identified 63% of patients as low risk with a 5-year ROR of 10%, whereas high-risk patients (37%) had a 5-year ROR of 21%, with a hazard ratio (HR) of 2.16 (p = .004). This remained significant in a multivariate model that included number of lymph nodes retrieved and microsatellite instability. In the T3 microsatellite-stable subgroup (n = 301), ColoPrint classified 59% of patients as low risk with a 5-year ROR of 9.9%. High-risk patients (31%) had a 22.4% ROR (HR: 2.41; p = .005). In contrast, the NCCN clinical high-risk factors were unable to distinguish high- and low-risk patients (15% vs. 13% ROR; p = .55). CONCLUSION: ColoPrint significantly improved prognostic accuracy independent of microsatellite status or clinical variables, facilitating the identification of patients at higher risk who might be considered for additional treatment.


Subject(s)
Colorectal Neoplasms/genetics , Gene Expression Profiling , Neoplasm Recurrence, Local/genetics , Adult , Aged , Aged, 80 and over , Colorectal Neoplasms/pathology , Female , Gene Expression Regulation, Neoplastic/genetics , Genomics , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/diagnosis , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Netherlands , Prognosis , Risk Assessment
10.
BMC Cancer ; 14: 660, 2014 Sep 10.
Article in English | MEDLINE | ID: mdl-25208577

ABSTRACT

BACKGROUND: The nonreceptor tyrosine kinase Src regulates multiple pathways critical to tumor proliferation, chemoresistance, and epithelial-to-mesenchymal transition. It is robustly activated after acute oxaliplatin exposure and in acquired oxaliplatin resistance in vitro and in vivo, but not after 5-fluorouracil (5-FU) alone. However, activation of Src and its substrate focal adhesion kinase (FAK) in metastatic colorectal cancer treated with oxaliplatin has not been investigated. We retrospectively evaluated the activation of Src and FAK in hepatic metastases of colorectal cancer and correlated these findings with the clinical outcomes of patients treated with oxaliplatin. METHODS: Samples from 170 hepatic resections from patients with metastatic colorectal cancer from two cohorts were examined by IHC for expression of Src, activated Src (pSrc), FAK, and activated FAK (pFAK). Patients in the first cohort (120 patients) were analyzed for immunohistochemical protein expression and for survival outcomes. In the second cohort, tissue was collected from 25 patients undergoing sequential hepatic metastasectomies (n = 50). RESULTS: In the first cohort, Src activation was positively correlated with pFAK expression (P = 0.44, P < 0.001). Patients pretreated with oxaliplatin and 5-FU demonstrated increased expression of pFAK (P = 0.017) compared with patients treated with 5-FU alone or irinotecan/5-FU. Total Src expression was associated with the number of neoadjuvant cycles of oxaliplatin (P = 0.047). In the second cohort, pFAK expression was higher following exposure to oxaliplatin. When patients were stratified by expression of pFAK and pSrc, an inverse relationship was observed between relapse-free survival rates and levels of both pFAK (21.1 months, 16.5 months, and 7.4 months for low, medium, and high levels of pFAK, respectively; P = 0.026) and pSrc (19.6 months, 13.6 months, and 8.2 months, respectively; P = 0.013). No differences in overall survival were detected. CONCLUSIONS: Patients administered neoadjuvant oxaliplatin demonstrated higher levels of Src pathway signaling in hepatic metastases, a finding associated with poorer relapse-free survival. These results are consistent with prior in vitro studies and support the idea that combining Src inhibition with platinum chemotherapy warrants further investigation in metastatic colorectal cancer.


Subject(s)
Antineoplastic Agents/therapeutic use , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/surgery , Focal Adhesion Kinase 1/metabolism , Organoplatinum Compounds/therapeutic use , Proto-Oncogene Proteins pp60(c-src)/metabolism , Camptothecin/analogs & derivatives , Camptothecin/therapeutic use , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Fluorouracil/therapeutic use , Hepatectomy , Humans , Irinotecan , Neoplasm Metastasis , Oxaliplatin , Survival Analysis , Treatment Outcome
11.
Mater Horiz ; 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39319678

ABSTRACT

With substantial temperature differentials between summer and winter in polar regions, there exists a pressing necessity for flexible sensors capable of functioning across a broad temperature spectrum to facilitate the construction of a more intelligent human-machine interface. Nevertheless, developing flexible sensors resilient to extremely low temperatures remains a significant challenge. In this study, we present an organohydrogel capable of functioning ranging from ambient to -78 °C, enabling real-time monitoring of multi-source signals, including motion, physiology, speech, and pressure. We synthesize organohydrogel employing a singular methodology: interpenetrating network structures as matrix frameworks, dynamic hydrophobic linkages as the physical cross-linking points, and incorporating a bionic binder. H-Bonding and chain entanglement synergistic supramolecular interactions build the organohydrogel matrix with microphase-separated domains, which, together with the combination of binary solvents and inorganic salts, allows it to exhibit excellent properties, including large stretchability (≈1700%), high ionic conductivity (1.57 S m-1), admirable sensing sensitivity performance (gauge factor: GF = 6.47, S = 0.32 kPa-1), an exceptionally low-pressure detection threshold (≈1 Pa), enables wireless transmission of distress signals through human-machine interaction even at -78 °C, which makes it possible to use it in polar exploration and to give robots a "sense of touch" for a variety of deep-diving tasks.

12.
Cancer ; 117(20): 4623-32, 2011 Oct 15.
Article in English | MEDLINE | ID: mdl-21456008

ABSTRACT

BACKGROUND: It is hypothesized that BRAF mutant cancers represent a discrete subset of metastatic colorectal cancer (CRC) defined by poorer survival. This study investigates whether BRAF mutant CRC is further defined by a distinct pattern of metastatic spread and explores the impact of BRAF mutation and microsatellite instability (MSI) on prognosis in metastatic CRC. METHODS: By using prospective clinical data and molecular analyses from 2 major centers (Royal Melbourne Hospital and The University of Texas MD Anderson Cancer Center), patients with known BRAF mutation status were analyzed for clinical characteristics, survival, and metastatic sites. RESULTS: The authors identified 524 metastatic CRC patients where BRAF mutation status was known; 57 (11%) were BRAF mutant tumors. BRAF mutant tumors were significantly associated with right-sided primary tumor, MSI, and poorer survival (median, 10.4 months vs 34.7 months, P < .001). A distinct pattern of metastatic spread was observed in BRAF mutant tumors, namely higher rates of peritoneal metastases (46% vs 24%, P = .001), distant lymph node metastases (53% vs 38%, P = .008), and lower rates of lung metastases (35% vs 49%, P = .049). In additional survival analyses, MSI tumors had significantly poorer survival compared with microsatellite stable tumors (22.1 months vs 11.1 months, P = .017), but this difference was not evident in the BRAF mutant population. CONCLUSIONS: The pattern of metastatic spread observed in this study further defines BRAF mutant CRC as a discrete disease subset. The authors demonstrated that, unlikely early stage disease, MSI is associated with poorer survival in metastatic CRC, although this is driven by its association with BRAF mutation.


Subject(s)
Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Microsatellite Instability , Mutation , Proto-Oncogene Proteins B-raf/genetics , Aged , Aged, 80 and over , Colorectal Neoplasms/mortality , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Multivariate Analysis , Predictive Value of Tests , Prognosis , Prospective Studies
13.
Clin Cancer Res ; 23(16): 4578-4591, 2017 Aug 15.
Article in English | MEDLINE | ID: mdl-28400427

ABSTRACT

Purpose: Liquid biopsies allow the tracking of clonal dynamics and detection of mutations during treatment.Experimental Design: We evaluated under blinded conditions the ability of cell-free DNA (cfDNA) to detect RAS/BRAF mutations in the plasma of 42 metastatic colorectal cancer patients treated on a phase Ib/II trial of FOLFOX and dasatinib, with or without cetuximab.Results: Prior to treatment, sequencing of archival tissue detected mutations in 25 of 42 patients (60%), while the cfDNA assay detected mutations in 37 of 42 patients (88%). Our cfDNA assay detected mutations with allele frequencies as low as 0.01%. After exposure to treatment, 41 of 42 patients (98%) had a cfDNA-detected RAS/BRAF mutation. Of 21 patients followed with serial measurements who were RAS/BRAF mutant at baseline, 11 (52%) showed additional point mutation following treatment and 3 (14%) no longer had detectable levels of another mutant allele. Of RAS/BRAF wild-type tumors at baseline, 4 of 5 (80%) showed additional point mutations. cfDNA quantitative measurements from this study closely mirrored changes in CEA and CT scan results, highlighting the importance of obtaining quantitative data beyond the mere presence of a mutation.Conclusions: Our findings demonstrate the development of new RAS/BRAF mutations in patients regardless of whether they had preexisting mutations in the pathway, demonstrating a convergent evolutionary pattern. Clin Cancer Res; 23(16); 4578-91. ©2017 AACR.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cell-Free Nucleic Acids/analysis , Colorectal Neoplasms/drug therapy , Drug Resistance, Neoplasm/drug effects , Cell-Free Nucleic Acids/genetics , Cetuximab/administration & dosage , Clonal Evolution , Colorectal Neoplasms/blood , Colorectal Neoplasms/genetics , Dasatinib/administration & dosage , Drug Resistance, Neoplasm/genetics , Fluorouracil/administration & dosage , Gene Frequency , Humans , Leucovorin/administration & dosage , Mutation , Organoplatinum Compounds/administration & dosage , Outcome Assessment, Health Care/methods , Proto-Oncogene Proteins B-raf/genetics , ras Proteins/genetics
14.
Mol Cancer Ther ; 16(7): 1435-1442, 2017 07.
Article in English | MEDLINE | ID: mdl-28468778

ABSTRACT

Developing realistic preclinical models using clinical samples that mirror complex tumor biology and behavior are vital to advancing cancer research. While cell line cultures have been helpful in generating preclinical data, the genetic divergence between these and corresponding primary tumors has limited clinical translation. Conversely, patient-derived xenografts (PDX) in colorectal cancer are highly representative of the genetic and phenotypic heterogeneity in the original tumor. Coupled with high-throughput analyses and bioinformatics, these PDXs represent robust preclinical tools for biomarkers, therapeutic target, and drug discovery. Successful PDX engraftment is hypothesized to be related to a series of anecdotal variables namely, tissue source, cancer stage, tumor grade, acquisition strategy, time to implantation, exposure to prior systemic therapy, and genomic heterogeneity of tumors. Although these factors at large can influence practices and patterns related to xenotransplantation, their relative significance in determining the success of establishing PDXs is uncertain. Accordingly, we systematically examined the predictive ability of these factors in establishing PDXs using 90 colorectal cancer patient specimens that were subcutaneously implanted into immunodeficient mice. Fifty (56%) PDXs were successfully established. Multivariate analyses showed tissue acquisition strategy [surgery 72.0% (95% confidence interval (CI): 58.2-82.6) vs. biopsy 35% (95% CI: 22.1%-50.6%)] to be the key determinant for successful PDX engraftment. These findings contrast with current empiricism in generating PDXs and can serve to simplify or liberalize PDX modeling protocols. Better understanding the relative impact of these factors on efficiency of PDX formation will allow for pervasive integration of these models in care of colorectal cancer patients. Mol Cancer Ther; 16(7); 1435-42. ©2017 AACR.


Subject(s)
Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Disease Models, Animal , Xenograft Model Antitumor Assays/methods , Animals , Colorectal Neoplasms/pathology , Female , Humans , Male , Mice , Neoplasm Staging
15.
Clin Cancer Res ; 23(15): 4146-4154, 2017 Aug 01.
Article in English | MEDLINE | ID: mdl-28280091

ABSTRACT

Purpose: Aberrant activation of the intracellular tyrosine kinase Src has been implicated as a mechanism of acquired chemotherapy resistance in metastatic colorectal cancer (mCRC). Here, the oral tyrosine kinase Src inhibitor, dasatinib, was investigated in combination with FOLFOX and cetuximab.Experimental Design: We performed a phase IB/II study of 77 patients with previously treated mCRC. Primary objectives were to determine the maximum tolerated dose, dose-limiting toxicities (DLT), pharmacodynamics, and efficacy. Using a 3 + 3 design, patients received FOLFOX6 with cetuximab and escalating doses of dasatinib (100, 150, 200 mg daily), followed by a 12-patient expansion cohort at 150 mg. Phase II studies evaluated FOLFOX plus dasatinib 100 mg in KRAS c12/13mut patients or in combination with cetuximab if KRAS c12/13WT FAK and paxillin were utilized as surrogate blood biomarkers of Src inhibition, and paired biopsies of liver metastases were obtained in patients in the expansion cohort.Results: In phase IB, the DLTs were grade 3/4 fatigue (20%) and neutropenia (23%). In phase II, grade 3/4 fatigue (23%) and pleural effusions (11%) were present. Response rates were 20% (6 of 30) in the phase IB escalation and expansion cohort and 13% (3 of 24) and 0% (0 of 23) in the KRAS c12/13WT and mutant cohorts of phase II, respectively. Median progression-free survival was 4.6, 2.3, and 2.3 months, respectively. There was no evidence of Src inhibition based on surrogate blood biomarkers or paired tumor biopsies.Conclusions: The combination of dasatinib plus FOLFOX with or without cetuximab showed only modest clinical activity in refractory colorectal cancer. This appears to be primarily due to a failure to fully inhibit Src at the achievable doses of dasatinib. The combination of dasatinib plus FOLFOX with or without cetuximab did not show meaningful clinical activity in refractory colorectal cancer due to failure to fully inhibit Src. Clin Cancer Res; 23(15); 4146-54. ©2017 AACR.


Subject(s)
Cetuximab/administration & dosage , Colorectal Neoplasms/drug therapy , Dasatinib/administration & dosage , ErbB Receptors/genetics , Proto-Oncogene Proteins p21(ras)/genetics , src-Family Kinases/genetics , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , CSK Tyrosine-Protein Kinase , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Disease-Free Survival , ErbB Receptors/antagonists & inhibitors , Female , Fluorouracil/administration & dosage , Humans , Leucovorin/administration & dosage , Male , Maximum Tolerated Dose , Middle Aged , Organoplatinum Compounds/administration & dosage , src-Family Kinases/antagonists & inhibitors
16.
Genome Biol ; 18(1): 98, 2017 05 24.
Article in English | MEDLINE | ID: mdl-28535802

ABSTRACT

BACKGROUND: Non-coding RNAs have been drawing increasing attention in recent years as functional data suggest that they play important roles in key cellular processes. N-BLR is a primate-specific long non-coding RNA that modulates the epithelial-to-mesenchymal transition, facilitates cell migration, and increases colorectal cancer invasion. RESULTS: We performed multivariate analyses of data from two independent cohorts of colorectal cancer patients and show that the abundance of N-BLR is associated with tumor stage, invasion potential, and overall patient survival. Through in vitro and in vivo experiments we found that N-BLR facilitates migration primarily via crosstalk with E-cadherin and ZEB1. We showed that this crosstalk is mediated by a pyknon, a short ~20 nucleotide-long DNA motif contained in the N-BLR transcript and is targeted by members of the miR-200 family. In light of these findings, we used a microarray to investigate the expression patterns of other pyknon-containing genomic loci. We found multiple such loci that are differentially transcribed between healthy and diseased tissues in colorectal cancer and chronic lymphocytic leukemia. Moreover, we identified several new loci whose expression correlates with the colorectal cancer patients' overall survival. CONCLUSIONS: The primate-specific N-BLR is a novel molecular contributor to the complex mechanisms that underlie metastasis in colorectal cancer and a potential novel biomarker for this disease. The presence of a functional pyknon within N-BLR and the related finding that many more pyknon-containing genomic loci in the human genome exhibit tissue-specific and disease-specific expression suggests the possibility of an alternative class of biomarkers and therapeutic targets that are primate-specific.


Subject(s)
Colorectal Neoplasms/genetics , Epithelial-Mesenchymal Transition/genetics , Gene Expression Regulation, Neoplastic , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , RNA, Long Noncoding/genetics , Adult , Aged , Aged, 80 and over , Animals , Cadherins/genetics , Cadherins/metabolism , Cell Movement , Cell Proliferation , Cohort Studies , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Female , Genetic Loci , HCT116 Cells , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Leukemia, Lymphocytic, Chronic, B-Cell/mortality , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , MicroRNAs/genetics , MicroRNAs/metabolism , Middle Aged , Neoplasm Invasiveness , Neoplasm Staging , Nucleotide Motifs , RNA, Long Noncoding/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Survival Analysis , Transcription, Genetic , Zinc Finger E-box-Binding Homeobox 1/genetics , Zinc Finger E-box-Binding Homeobox 1/metabolism
17.
J Biomol Struct Dyn ; 23(6): 635-40, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16615809

ABSTRACT

The extremely complicated nature of many biological problems makes them bear the features of fuzzy sets, such as with vague, imprecise, noisy, ambiguous, or input-missing information For instance, the current data in classifying protein structural classes are typically a fuzzy set To deal with this kind of problem, the AAPCA (Amino Acid Principal Component Analysis) approach was introduced. In the AAPCA approach the 20-dimensional amino acid composition space is reduced to an orthogonal space with fewer dimensions, and the original base functions are converted into a set of orthogonal and normalized base functions The advantage of such an approach is that it can minimize the random errors and redundant information in protein dataset through a principal component selection, remarkably improving the success rates in predicting protein structural classes It is anticipated that the AAPCA approach can be used to deal with many other classification problems in proteins as well.


Subject(s)
Amino Acids/chemistry , Principal Component Analysis/methods , Proteins/chemistry , Computational Biology , Models, Molecular , Protein Conformation , Proteins/classification , Sequence Analysis, Protein
18.
Clin Colorectal Cancer ; 15(2): e1-7, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26810202

ABSTRACT

BACKGROUND: Colorectal high-grade neuroendocrine carcinomas (HGNEC) are a rare but aggressive group of malignancies without standard management recommendations. METHODS: We retrospectively reviewed the records of 100 consecutive patients with histologically confirmed colorectal HGNEC diagnosed at MD Anderson Cancer Center between 1991 and 2013. RESULTS: In our cohort, most tumors (89%) were small cell carcinoma, and most (60%) involved the sigmoid or the anorectal regions. Sixty-four patients (64%) presented with metastatic disease at diagnosis. Striking epidemiological and clinical differences between those established in small cell lung cancer (SCLC) and our cohort were noted, including significantly lower rates of smoking and lower risk of bone, brain metastases. Over 30% of the tumors were found associated with an adenoma. Median overall survival (OS) of the cohort was 14.7 months, with 2-year and 5-year OS rates of 23% and 8%, respectively. In patients with localized disease, multimodality therapy was associated with a trend toward improved median OS (20.4 vs. 15.4 months; P = .08). Metastases at presentation (OS 20.63 vs. 8.7 months; localized vs metastatic disease at presentation; P < .001) and elevated lactate dehydrogenase levels were strongly associated with a worse outcome. CONCLUSION: In comparison to SCLC, less than half of the patients with colorectal HGNEC have history of smoking; metastatic patterns are also different between the 2 cancers. Nevertheless, HGNEC also has an aggressive biology, with the rectum being the most common site of origin. For localized disease, a multimodality approach seems to be associated with better outcomes, while systemic chemotherapy is the mainstay of treatment for advanced disease.


Subject(s)
Carcinoma, Neuroendocrine/mortality , Carcinoma, Neuroendocrine/pathology , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Carcinoma, Neuroendocrine/therapy , Colorectal Neoplasms/therapy , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies
19.
J Mol Biol ; 341(1): 271-9, 2004 Jul 30.
Article in English | MEDLINE | ID: mdl-15312778

ABSTRACT

Proteomics was used to identify a protein encoded by ORF 3a in a SARS-associated coronavirus (SARS-CoV). Immuno-blotting revealed that interchain disulfide bonds might be formed between this protein and the spike protein. ELISA indicated that sera from SARS patients have significant positive reactions with synthesized peptides derived from the 3a protein. These results are concordant with that of a spike protein-derived peptide. A tendency exists for co-mutation between the 3a protein and the spike protein of SARS-CoV isolates, suggesting that the function of the 3a protein correlates with the spike protein. Taken together, the 3a protein might be tightly correlated to the spike protein in the SARS-CoV functions. The 3a protein may serve as a new clinical marker or drug target for SARS treatment.


Subject(s)
Severe acute respiratory syndrome-related coronavirus/metabolism , Viral Proteins/metabolism , Animals , Chlorocebus aethiops , Disulfides/metabolism , Humans , Membrane Glycoproteins/metabolism , Phylogeny , Proteomics , Severe acute respiratory syndrome-related coronavirus/chemistry , Severe acute respiratory syndrome-related coronavirus/genetics , Sequence Analysis, Protein , Spike Glycoprotein, Coronavirus , Vero Cells , Viral Envelope Proteins/metabolism , Viral Proteins/chemistry , Viral Proteins/genetics , Viroporin Proteins
20.
Med Chem ; 1(3): 209-13, 2005 May.
Article in English | MEDLINE | ID: mdl-16787316

ABSTRACT

According to the "distorted key" theory as elaborated in a review article years ago (Chou, K.C.: Analytical Biochemistry, 1996, 233, 1-14), the knowledge of the cleavable peptides by SARS-CoV M(pro) (severe acute respiratory syndrome coronavirus main proteinase) can provide very useful insights on developing drugs against SARS. In view of this, the softwares, ZCURVE_CoV 1.0 and ZCURVE_CoV 2.0 (http://tubic.tju.edu.cn/sars/), developed recently for SARS-Coronavirus are used to analyze the 36 complete SARS-Coronavirus RNA sequences in the gene bank NCBI (http://www.ncbi.nlm.nih.gov/) from different sources for protein coding genes, and to search for the cleavage sites of SARS-CoV M(pro) in polyproteins pp1a and pp1ab. A total of 396 cleavage points are found in the 36 SARS-Coronavirus and 11 cleavable octapeptides abstracted from the 396 cleavage sites. The statistical distributions of amino acids for the cleavable octapeptides at the subsites R4, R3, R2, R1, R1', R2', R3' and R4' are calculated. The cleavage-specific positions are on R2, R1 and R1', and the positions R3 and R4 are featured by some certain specificity for SARS-CoV M(pro). The structural characters of amino acid residues around the cleavage-specific positions are discussed. Two most promising octapeptides, i.e., NH(2)-ATLQ downward arrowAIAS-COOH and NH(2)-ATLQ downward arrowAENV-COOH, are selected to be the candidates for chemical modification, converting into the inhibitors of SARS-CoV M(pro). A possible strategy to convert a cleavable octapeptide by SARS enzyme into a drug candidate against SARS is elucidated.


Subject(s)
Antiviral Agents/chemistry , Cysteine Endopeptidases/chemistry , Cysteine Proteinase Inhibitors/chemistry , Drug Design , Oligopeptides/chemistry , Viral Proteins/antagonists & inhibitors , Viral Proteins/chemistry , Amino Acid Sequence , Antiviral Agents/pharmacology , Computational Biology , Coronavirus 3C Proteases , Cysteine Endopeptidases/genetics , Cysteine Proteinase Inhibitors/pharmacology , Genome, Viral , Molecular Sequence Data , Oligopeptides/genetics , Oligopeptides/pharmacology , Severe acute respiratory syndrome-related coronavirus/drug effects , Severe acute respiratory syndrome-related coronavirus/enzymology , Severe acute respiratory syndrome-related coronavirus/genetics , Sequence Analysis, Protein , Sequence Analysis, RNA , Software , Viral Proteins/genetics
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