To prospectively determine the diagnostic accuracy of diffusion-weighted magnetic resonance (MR) imaging for discrimination of malignant neck nodes due to lymphoma, squamous cell carcinoma (SCC), and ...undifferentiated nasopharyngeal carcinoma (NPC), with histologic findings and imaging criteria as reference standards.
Ethics committee approval and informed consent were obtained. Patients with malignant lymphadenopathy underwent 1.5-T diffusion-weighted MR imaging. A region of interest was drawn around the malignant node on apparent diffusion coefficient (ADC) maps; ADC values were compared (Kruskal-Wallis test). Receiver operating characteristic analysis was employed to investigate whether ADC values could aid in discrimination among malignancies.
Forty-three patients (34 men, nine women; mean age, 54 years) with 43 nodes underwent imaging. Mean ADC values for lymphoma (n = 8), NPC (n = 17), and SCC (n = 18) were (0.664 +/- 0.071 standard deviation) x 10(-3) mm(2)/sec, (0.802 +/- 0.128) x 10(-3) mm(2)/sec, and (1.057 +/- 0.169) x 10(-3) mm(2)/sec, respectively, with significant differences between SCC and lymphoma or NPC (P < .001) and between NPC and lymphoma (P = .04). To optimize sensitivity and specificity with equal weighting, ADC threshold values for distinguishing between SCC and NPC, between SCC and lymphoma, and between NPC and lymphoma were 0.894 x 10(-3) mm(2)/sec, 0.824 x 10(-3) mm(2)/sec, and 0.694 x 10(-3) mm(2)/sec, respectively. To produce a 100% specificity while sensitivity is maximized, the following ADC threshold values were obtained for prediction of differentiation between malignancies: (a) SCC versus lymphoma, greater than 0.824 x 10(-3) mm(2)/sec (sensitivity, 94%), and lymphoma versus SCC, less than 0.767 x 10(-3) mm(2)/sec (sensitivity 88%); (b) NPC versus SCC, less than 0.764 x 10(-3) mm(2)/sec (sensitivity, 47%), and SCC versus NPC, greater than 1.093 x 10(-3) mm(2)/sec (sensitivity, 39%); (c) NPC versus lymphoma, greater than 0.788 x 10(-3) mm(2)/sec (sensitivity, 53%), and lymphoma versus NPC, no suitable threshold value.
Diffusion-weighted MR imaging shows significant differences among malignant nodes of SCC, lymphoma, and NPC. ADC threshold values can help distinguish SCC from lymphoma.
http://radiology.rsnajnls.org/cgi/content/full/2451061804/DC1.
Purpose NRG Oncology/RTOG 1203 was designed to compare patient-reported acute toxicity and health-related quality of life during treatment with standard pelvic radiation or intensity-modulated ...radiation therapy (IMRT) in women with cervical and endometrial cancer. Methods Patients were randomly assigned to standard four-field radiation therapy (RT) or IMRT radiation treatment. The primary end point was change in patient-reported acute GI toxicity from baseline to the end of RT, measured with the bowel domain of the Expanded Prostate Cancer Index Composite (EPIC). Secondary end points included change in patient-reported urinary toxicity, change in GI toxicity measured with the Patient-Reported Outcome Common Terminology Criteria for Adverse Events, and quality of life measured with the Trial Outcome Index. Results From 2012 to 2015, 289 patients were enrolled, of whom 278 were eligible. Between baseline and end of RT, the mean EPIC bowel score declined 23.6 points in the standard RT group and 18.6 points in the IMRT group ( P = .048), the mean EPIC urinary score declined 10.4 points in the standard RT group and 5.6 points in the IMRT group ( P = .03), and the mean Trial Outcome Index score declined 12.8 points in the standard RT group and 8.8 points in the IMRT group ( P = .06). At the end of RT, 51.9% of women who received standard RT and 33.7% who received IMRT reported frequent or almost constant diarrhea ( P = .01), and more patients who received standard RT were taking antidiarrheal medications four or more times daily (20.4% v 7.8%; P = .04). Conclusion Pelvic IMRT was associated with significantly less GI and urinary toxicity than standard RT from the patient's perspective.
Accurate target definition is critical for the appropriate application of radiation therapy. In 2008, the Radiation Therapy Oncology Group (RTOG) published an international collaborative atlas to ...define the clinical target volume (CTV) for intensity modulated pelvic radiation therapy in the postoperative treatment of endometrial and cervical cancer. The current project is an updated consensus of CTV definitions, with removal of all references to bony landmarks and inclusion of the para-aortic and inferior obturator nodal regions.
An international consensus guideline working group discussed modifications of the current atlas and areas of controversy. A document was prepared to assist in contouring definitions. A sample case abdominopelvic computed tomographic image was made available, on which experts contoured targets. Targets were analyzed for consistency of delineation using an expectation-maximization algorithm for simultaneous truth and performance level estimation with kappa statistics as a measure of agreement between observers.
Sixteen participants provided 13 sets of contours. Participants were asked to provide separate contours of the following areas: vaginal cuff, obturator, internal iliac, external iliac, presacral, common iliac, and para-aortic regions. There was substantial agreement for the common iliac region (sensitivity 0.71, specificity 0.981, kappa 0.64), moderate agreement in the external iliac, para-aortic, internal iliac and vaginal cuff regions (sensitivity 0.66, 0.74, 0.62, 0.59; specificity 0.989, 0.966, 0.986, 0.976; kappa 0.60, 0.58, 0.52, 0.47, respectively), and fair agreement in the presacral and obturator regions (sensitivity 0.55, 0.35; specificity 0.986, 0.988; kappa 0.36, 0.21, respectively). A 95% agreement contour was smoothed and a final contour atlas was produced according to consensus.
Agreement among the participants was most consistent in the common iliac region and least in the presacral and obturator nodal regions. The consensus volumes formed the basis of the updated NRG/RTOG Oncology postoperative atlas. Continued patterns of recurrence research are encouraged to refine these volumes.
Arginine is an amino acid critically involved in multiple cellular processes including the syntheses of nitric oxide and polyamines, and is a direct activator of mTOR, a nutrient-sensing kinase ...strongly implicated in carcinogenesis. Yet, it is also considered as a non- or semi-essential amino acid, due to normal cells' intrinsic ability to synthesize arginine from citrulline and aspartate via ASS1 (argininosuccinate synthase 1) and ASL (argininosuccinate lyase). As such, arginine can be used as a dietary supplement and its depletion as a therapeutic strategy. Strikingly, in over 70% of tumors, ASS1 transcription is suppressed, rendering the cells addicted to external arginine, forming the basis of arginine-deprivation therapy. In this review, we will discuss arginine as a signaling metabolite, arginine's role in cancer metabolism, arginine as an epigenetic regulator, arginine as an immunomodulator, and arginine as a therapeutic target. We will also provide a comprehensive summary of ADI (arginine deiminase)-based arginine-deprivation preclinical studies and an update of clinical trials for ADI and arginase. The different cell killing mechanisms associated with various cancer types will also be described.
Obesity is a risk factor in various types of cancer, including breast cancer. The disturbance of adipose tissue in obesity highly correlates with cancer progression and resistance to standard ...treatments such as chemo- and radio-therapies. In this study, in a syngeneic mouse model of triple-negative breast cancer (TNBC), diet-induced obesity (DIO) not only promoted tumor growth, but also reduced tumor response to radiotherapy. Serpine1 (Pai-1) was elevated in the circulation of obese mice and was enriched within tumor microenvironment. In vitro co-culture of human white adipocytes-conditioned medium (hAd-CM) with TNBC cells potentiated the aggressive phenotypes and radioresistance of TNBC cells. Moreover, inhibition of both cancer cell autonomous and non-autonomous SERPINE1 by either genetic or pharmacological strategy markedly dampened the aggressive phenotypes and radioresistance of TNBC cells. Mechanistically, we uncovered a previously unrecognized role of SERPINE1 in DNA damage response. Ionizing radiation-induced DNA double-strand breaks (DSBs) increased the expression of SERPINE1 in cancer cells in an ATM/ATR-dependent manner, and promoted nuclear localization of SERPINE1 to facilitate DSB repair. By analyzing public clinical datasets, higher SERPINE1 expression in TNBC correlated with patients' BMI as well as poor outcomes. Elevated SERPINE1 expression and nuclear localization were also observed in radioresistant breast cancer cells. Collectively, we reveal a link between obesity and radioresistance in TNBC and identify SERPINE1 to be a crucial factor mediating obesity-associated tumor radioresistance.
Arginine plays diverse roles in cellular physiology. As a semi-essential amino acid, arginine deprivation has been used to target cancers with arginine synthesis deficiency. Arginine-deprived cancer ...cells exhibit mitochondrial dysfunction, transcriptional reprogramming and eventual cell death. In this study, we show in prostate cancer cells that arginine acts as an epigenetic regulator to modulate histone acetylation, leading to global upregulation of nuclear-encoded oxidative phosphorylation (OXPHOS) genes. TEAD4 is retained in the nucleus by arginine, enhancing its recruitment to the promoter/enhancer regions of OXPHOS genes and mediating coordinated upregulation in a YAP1-independent but mTOR-dependent manner. Arginine also activates the expression of lysine acetyl-transferases and increases overall levels of acetylated histones and acetyl-CoA, facilitating TEAD4 recruitment. Silencing of TEAD4 suppresses OXPHOS functions and prostate cancer cell growth in vitro and in vivo. Given the strong correlation of TEAD4 expression and prostate carcinogenesis, targeting TEAD4 may be beneficially used to enhance arginine-deprivation therapy and prostate cancer therapy.
Objective To test whether the combined use of total plasma/serum bilirubin (TSB) levels and clinical risk factors more accurately identifies infants who receive phototherapy than does the use of ...either method alone. Study design We recruited healthy infants of ≥35 weeks' gestation at 6 centers that practiced universal predischarge TSB screening. Transcutaneous bilirubin (TcB) was measured at 24 hours, with TSB at 24-60 hours and at 3- to 5- and 7- to 14-day follow-up visits. Clinical risk factors were identified systematically. Results Of 1157 infants, 1060 (92%) completed follow-up, and 982 (85%) had complete datasets for analysis. Infant characteristics included 25% were nonwhite and 55% were Hispanic/Latino; >90% were breastfed. During the first week, jaundice was documented in 84% of subjects. Predischarge TSB identified the 41 (4.2%) and 34 (3.5%) infants who received phototherapy before and after discharge, respectively. Prediction of postdischarge phototherapy was similar for combined clinical risk factors (earlier gestational age GA, bruising, positive direct antiglobulin test, Asian race, exclusive breastfeeding, blood type incompatibility, jaundice extent) and age-adjusted TSB (area under the curve AUC = .86 vs .87), but combined screening was better (AUC = .95). TcB/TSB combined with GA alone was equally predictive (AUC = .95; 95% CI .93-.97). Conclusions Jaundice is present in 4 of 5 (84%) healthy newborns. Predischarge TcB/TSB (adjusted for postnatal age) combined with specific clinical factors (especially GA) best predicts subsequent phototherapy use. Universal implementation of this strategy in the US should improve outcomes of healthy newborns discharged early.
X-ray fluorescence spectra obtained by the MESSENGER spacecraft orbiting Mercury indicate that the planet's surface differs in composition from those of other terrestrial planets. Relatively high ...Mg/Si and low Al/Si and Ca/Si ratios rule out a lunarlike feldspar-rich crust. The sulfur abundance is at least 10 times higher than that of the silicate portion of Earth or the Moon, and this observation, together with a low surface Fe abundance, supports the view that Mercury formed from highly reduced precursor materials, perhaps akin to enstatite chondrite meteorites or anhydrous cometary dust particles. Low Fe and Ti abundances do not support the proposal that opaque oxides of these elements contribute substantially to Mercury's low and variable surface reflectance.
The role of fatty acid metabolism, including both anabolic and catabolic reactions in cancer has gained increasing attention in recent years. Many studies have shown that aberrant expression of the ...genes involved in fatty acid synthesis or fatty acid oxidation correlate with malignant phenotypes including metastasis, therapeutic resistance and relapse. Such phenotypes are also strongly associated with the presence of a small percentage of unique cells among the total tumor cell population. This distinct group of cells may have the ability to self‐renew and propagate or may be able to develop resistance to cancer therapies independent of genetic alterations. Therefore, these cells are referred to as cancer stem cells/tumor‐initiating cells/drug‐tolerant persisters, which are often refractory to cancer treatment and difficult to target. Moreover, interconversion between cancer cells and cancer stem cells/tumor‐initiating cells/drug‐tolerant persisters may occur and makes treatment even more challenging. This review highlights recent findings on the relationship between fatty acid metabolism, cancer stemness and therapeutic resistance and prompts discussion about the potential mechanisms by which fatty acid metabolism regulates the fate of cancer cells and therapeutic resistance.
Poorly organized tumour vasculature often results in areas of limited nutrient supply and hypoxia. Despite our understanding of solid tumour responses to hypoxia, how nutrient deprivation regionally ...affects tumour growth and therapeutic response is poorly understood. Here, we show that the core region of solid tumours displayed glutamine deficiency compared with other amino acids. Low glutamine in tumour core regions led to dramatic histone hypermethylation due to decreased α-ketoglutarate levels, a key cofactor for the Jumonji-domain-containing histone demethylases. Using patient-derived (V600E)BRAF melanoma cells, we found that low-glutamine-induced histone hypermethylation resulted in cancer cell dedifferentiation and resistance to BRAF inhibitor treatment, which was largely mediated by methylation on H3K27, as knockdown of the H3K27-specific demethylase KDM6B and the methyltransferase EZH2 respectively reproduced and attenuated the low-glutamine effects in vitro and in vivo. Thus, intratumoral regional variation in the nutritional microenvironment contributes to tumour heterogeneity and therapeutic response.
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