A head-to-head comparison of [68Ga]Ga-DOTATATE and [68Ga]Ga-FAPI PET/CT in patients with nasopharyngeal carcinoma: a single-center, prospective study.

PURPOSE: We aimed to compare the staging efficiency of [68Ga]Ga-DOTATATE and [68Ga]Ga-FAPI PET/CT in nasopharyngeal carcinoma (NPC) patients. METHODS: Thirty-nine patients with pathologically confirmed NPC were enrolled in this prospective study. Each patient underwent paired [68Ga]Ga-DOTATATE and [68Ga]Ga-FAPI PET/CT on 2 successive days. The accuracy of two PET/CT for assessing T, N, and M stages was compared by using head-and-neck MRI, histopathologic diagnosis and follow-up results as reference standards. The radiotracer uptake derived from two PETs was also compared. RESULTS: For treatment-naïve patients, [68Ga]Ga-DOTATATE PET/CT showed identical sensitivity for the primary tumours but clearer tumor delineation induced by higher tumour-to-background (TBR) ratio (19.1 ± 8.7 vs. 12.4 ± 7.7, P = 0.003), compared with [68Ga]Ga-FAPI PET/CT. Regarding cervical lymph node (CLN) metastases, [68Ga]Ga-DOTATATE PET had significantly better sensitivity and accuracy based on neck sides (98% vs. 82%, P < 0.001; 99% vs. 88% P = 0.008), neck levels (98% vs. 78%, 99% vs. 97%; both P < 0.001) and individual nodes (89% vs. 56%, 91% vs. 76%; both P < 0.001), and higher TBR (8.1 ± 4.1 vs. 6.3 ± 3.7, P < 0.001). Additionally, [68Ga]Ga-DOTATATE PET/CT revealed higher sensitivity and accuracy for distant metastases (96% vs. 53%, 95% vs. 52%; both P < 0.001), particularly in bone metastases (99% vs. 49%, 97% vs. 49%; both P < 0.001). For post-treatment patients, [68Ga]Ga-DOTATATE PET/CT identified one more true-negative case than [68Ga]Ga-FAPI PET/CT. CONCLUSION: [68Ga]Ga-DOTATATE PET/CT performed better than [68Ga]Ga-FAPI PET/CT in visualizing the primary tumours, detecting the metastatic lesions and identifying the local recurrence, suggesting [68Ga]Ga-DOTATATE PET/CT may be superior to [68Ga]Ga-FAPI PET/CT for NPC staging.

Correlation between hippocampal radiation doses and psychological condition for patients with stage T1-2 nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: The study aimed to investigate the correlation between radiation doses to the hippocampi and the psychological status of patients with stage T1-2 nasopharyngeal carcinoma (NPC) undergoing intensity modulated radiotherapy (IMRT) and recommend proper hippocampal dose limits for preserving patients' psychological well-being. MATERIALS AND METHODS: A retrospective study was conducted involving 152 newly diagnosed NPC patients. The patients' psychological status was assessed using the Hospital Anxiety and Depression Scale (HADS) before and after radiotherapy. The hippocampi were manually delineated on treatment planning images, and dosimetric parameters were obtained from dose-volume histograms. Logistic regression analysis was performed to identify influential dosimetric factors associated with anxiety and depression. RESULTS: The results showed that several dosimetric parameters to the hippocampi were significantly associated with anxiety but not depression. The optimal cut-off value for the independent predictor of anxiety was determined as D40 to hippocampi > 1500 cGy. Patients with D40 to hippocampi > 1500 cGy showed a higher probability for anxiety after radiotherapy. CONCLUSION: This study provides insights into the relationship between radiation doses to the hippocampi and the psychological status of stage T1-2 NPC patients undergoing IMRT. It suggests the importance of hippocampal protection for preserving patients' psychological well-being. Further studies are needed to validate these results.

Gallium nitride-based resonant cavity light-emitting diode with single-longitudinal-mode emission.

A novel, to the best of our knowledge, gallium nitride (GaN)-based resonant cavity light-emitting diode (RCLED) with single-longitudinal-mode light emission was demonstrated. A Ta2O5/SiO2 dielectric distributed Bragg reflector (DBR) with a filter-film structure was adopted as the top mirror. In contrast to the flat-topped reflectivity spectrum of the conventional high-reflective-structure DBR, for this filter-film-structure DBR, there is a light-transmitting concave band on the reflectivity spectrum. Owing to the modulation effect of this band on the output light, a single-longitudinal-mode light emission with a full width at half maximum as low as 0.63 nm was realized. Furthermore, the novel RCLED exhibited better wavelength stability. With an increase in the injection current from 50 to 500 mA, the redshift of the emission peak was only 0.2 nm. This novel RCLED with ultra-narrowband emission has a high potential for application in optical communication systems and optical fiber sensing applications.

Wafer-Level Self-Packaging Design and Fabrication of MEMS Capacitive Pressure Sensors.

This paper reports a MEMS capacitive pressure sensor (CPS) based on the operating principle of touch mode. The CPS was designed and fabricated using wafer-level self-packaged MEMS processes. The variable capacitance sensing structure was vacuum-sealed in a cavity using the Si-glass anodic bonding technique, and the embedded Al feedthrough lines at the Si-glass interface were used to realize the electrical connections between the parallel plate electrodes and the electrode pads through Al vias. The optimal design of the CPS structure was performed to trade-off the performance and reliability using finite element simulation. The CPS based on a circular-shaped diaphragm with a radius of 2000 µm and a thickness of 40 µm exhibits good comprehensive performance with a sensitivity of 52.3 pF/MPa and a nonlinearity of 2.7%FS in the pressure range of 100-500 kPa when the ambient temperature is less than 50 °C.

Preliminary study on the diagnostic value of cardiac magnetic resonance feature tracking for malignant ventricular arrhythmias in non-ischemic dilated cardiomyopathy.

Background: Patients with nonischemic dilated cardiomyopathy (NIDCM) and malignant ventricular arrhythmia (MVA) often have a poor prognosis and a high risk of sudden cardiac death. Although the diagnosis of MVA is straightforward by electrocardiogram (ECG), the underlying abnormalities of ventricular mechanics in these patients are unknown. This study aims to preliminarily explore the value of cardiac magnetic resonance feature tracking (CMR-FT) for MVA in dilated cardiomyopathy. Methods: In this retrospective study, patients with NIDCM who met inclusion criteria were divided into an MVA group and a non-MVA group (included from January 2018 to September 2021). The interobserver agreement of myocardial strain parameters, including global longitudinal strain (GLS), global circumferential strain (GCS) and global radial strain (GRS), were tested. The GLS, GCS, GRS, left ventricular ejection fraction (LVEF), Tpeak-Tend interval on ECG and brain natriuretic peptide (BNP) were compared between groups. Single-factor and multifactor receiver operating characteristic (ROC) curve analyses were conducted to calculate the area under the ROC curve (AUC), cut-off point, sensitivity, and specificity of these parameters in predicting MVA in NIDCM. Results: A total of 161 NIDCM patients were included (54 in the MVA group). GLS, GCS, and GRS had good interobserver agreement (all intraclass correlation coefficients >0.80). The absolute GLS and GCS, GRS and LVEF were lower in the MVA group than the non-MVA group (P<0.001), Tpeak-Tend and BNP were higher (P<0.001). Single-factor ROC curve analysis showed that GLS, GCS and GRS had certain diagnostic value for MVA (AUC =0.795, 0.802, and 0.754, respectively). Among them, GCS had higher sensitivity and specificity (GCS 0.796/0.776, GLS 0.778/0.757, GRS 0.741/0.692). Multifactor ROC curve analysis showed the combination of GLS and GCS (AUC =0.810), the combination of GCS and GRS (AUC =0.802), the combination of GLS and GRS (AUC =0.787), the combination of GLS, GCS, and GRS (AUC =0.810). Conclusions: The three-dimensional myocardial strain parameters (especially GLS and GCS) measured by CMR-FT had certain diagnostic value and could reflect the underlying abnormality of ventricular mechanics of NIDCM with MVA.

The psychological status in patients with nasopharyngeal carcinoma during radiotherapy.

PURPOSE: The psychological status of nasopharyngeal carcinoma (NPC) patients cannot be ignored. Few studies have studied the dynamic changes and influencing factors of psychological status in NPC patients during radiotherapy. The purpose of this study was to investigate the changing trends and risk factors of anxiety and depression in NPC patients during radiotherapy. METHODS: Demographic and clinical data of 232 newly treated NPC patients were collected. Before radiotherapy, the fourth week, and the end of radiotherapy were observational timepoints. Anxiety and depression states were evaluated by the hospital anxiety and depression scale. RESULTS: Scores of anxiety before radiotherapy, in the fourth week and at the end of radiotherapy were 6.32 ± 3.19, 7.87 ± 3.49, and 9.08 ± 3.69, respectively (P < 0.001). Incidence rates of anxiety were 34.0%, 55.1%, and 64.0% (P < 0.001). Depression scores were 5.31 ± 3.19, 7.07 ± 3.63, and 8.32 ± 3.89 (P < 0.001). Incidence rates of depression were 25.0%, 43.9%, and 56.0% (P < 0.001). Gender, age, education level, smoking, and treatment-related toxicity scores (P < 0.05) were independent risk factors for anxiety in patients with NPC during radiotherapy, while age, education level, and treatment-related toxicity scores (P < 0.05) were independent risk factors for depression in these patients. CONCLUSION: The incidence and degree of anxiety and depression in NPC patients increased during radiotherapy. Age, education level, and treatment-related side effects influenced anxiety and depression. More psychological nursing should be given to the NPC patients who are more likely to suffer from psychological distress.

Comparative transcriptomic analysis reveals the regulatory effects of inorganic nitrogen on the biosynthesis of Monascus pigments and citrinin.

Monascus spp. and its secondary metabolites have been widely applied in foods and medicines for thousands of years in eastern Asia. Nitrogen sources are essential nutrients for the growth and metabolism of Monascus spp. Our previous study found that inorganic nitrogen sources (especially NH4Cl and NH4NO3) promoted the biosynthesis of Monascus pigments (MPs) and inhibited the production of citrinin. The objective of the present study was to investigate the regulatory mechanism of inorganic nitrogen on the biosynthesis of MPs and citrinin by the comparative transcriptional approach (RNA sequencing combined with RT-qPCR). Results indicated that the submerged fermentation of M. purpureus M3103 with NH4Cl or NH4NO3 as the sole nitrogen source can significantly increase the yields of MPs (especially for Monascus orange and red pigments) and decrease citrinin production, compared with the organic nitrogen source (peptone group). Comparative transcriptomic profiling by RNA sequencing found that the numbers of differentially expressed genes (DEGs) between different experimental groups-M group (peptone group) vs. ML group (NH4Cl group), and M group (peptone group) vs. MX group (NH4NO3 group), were 722 and 1287, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that genes involved in carbon and nitrogen metabolism, biosynthesis of amino acids were up-regulated by NH4Cl and NH4NO3, which would produce more biosynthetic precursors for MPs. Whereas, the inorganic nitrogen source (both of NH4Cl and NH4NO3) down-regulated the expression levels of genes involved in tyrosine metabolism. In addition, NR analysis indicated that the essential genes and transcription factors involved in the biosynthesis pathway of citrinin were down-regulated by NH4Cl and NH4NO3. These results indicated that NH4Cl or NH4NO3 as a nitrogen source for M. purpureus M3103 can significantly promote the precursor synthesis of Monascus pigments, but reduce the transcription of polyketide synthase for citrinin, and therefore significantly increase Monascus pigments production and decrease citrinin formation. These findings will facilitate a comprehensive understanding of the regulatory mechanisms of inorganic nitrogen in the biosynthesis of secondary metabolites in M. purpureus, and would benefit the application of M. purpureus in the production of MPs.

Fabrications of L-band LiNbO3-based SAW Resonators for Aerospace Applications.

High frequency surface acoustic wave (SAW) technology offers many opportunities for aerospace applications in passive wireless sensing and communication. This paper presents the design, simulation, fabrication, and test of an L-band SAW resonator based on 128° Y-X LiNbO3 substrate. The design parameters of SAW resonator were optimized by the finite element (FEM) method and the coupling-of-mode (COM) theory. Electron-beam lithography (EBL) technology was used to fabricate the submicron-scale of interdigital transducers (IDTs) and grating reflectors. The effects of some key EBL processes (e.g., the use of electron beam resist, the choice of metal deposition methods, the charge-accumulation effect, and the proximity-effect) on the fabrication precision of SAW devices were discussed. Experimentally, the LiNbO3-based SAW resonators fabricated using improved EBL technology exhibits a Rayleigh wave resonance peaks at 1.55 GHz with return loss about -12dB, and quality factor Q is 517. Based on this SAW resonator, the temperature and strain sensing tests were performed, respectively. The experimental results exhibit a well linear dependence of temperature/strain on frequency-shift, with a temperature sensitivity of 125.4 kHz/C and a strain sensitivity of -831 Hz/µÎµ, respectively.

A "time-frozen" technique in microchannel used for the thermodynamic studies of DNA origami.

The emergence of DNA origami greatly accelerated the development of DNA nanotechnology. A thorough understanding of origami thermodynamics is very important for both fundamental studies and practical applications. These thermodynamic transitions usually take place in several seconds or even less, and are very difficult to monitor by conventional methods. Numerous tests are required to characterize the origami molecule's behaviors at different temperatures, which is very labor-intensive and time-consuming. In this paper, an axially distributed temperature gradient along a capillary was formed in a spatially varying temperature field. In such a temperature gradient, the origami molecule's thermodynamic processes occur and remain stable at every position along the capillary's microchannel. It looks like the time of the thermodynamic process is frozen along the microchannel. With this method, the origami molecule's thermodynamic characteristics at different temperatures can be obtained in a single experiment, and rapid processes can be monitored with ease by conventional methods for an adequate time period at low cost. In order to show its potential abilities, this method has been demonstrated in applications which the origami's assembly, denaturation and strand displacement are carry out in a flowing or stationary solution.

Biomimetic Beetle-Inspired Flapping Air Vehicle Actuated by Ionic Polymer-Metal Composite Actuator.

During the last decades, the ionic polymer-metal composite (IPMC) received much attention because of its potential capabilities, such as large displacement and flexible bending actuation. In this paper, a biomimetic flapping air vehicle was proposed by combining the superiority of ionic polymer metal composite with the bionic beetle flapping principle. The blocking force was compared between casted IPMC and IPMC. The flapping state of the wing was investigated and the maximum displacement and flapping angle were measured. The flapping displacement under different voltage and frequency was tested. The flapping displacement of the wing and the support reaction force were measured under different frequency by experiments. The experimental results indicate that the high voltage and low frequency would get large flapping displacement.

Influence of grating parameters on the performance of a high-power blue external-cavity semiconductor laser.

The influence of grating parameters, including the diffraction efficiency and ruling density, on the performance of high-power blue external-cavity (EC) semiconductor lasers has been studied. We find that for the Littrow-type EC laser with a zeroth-order diffracted beam as a coupling output, the high zeroth-order diffraction efficiency benefits the high external light extraction efficiency, and the high first-order diffraction efficiency contributes to the low threshold current and the wide wavelength tuning bandwidth. By using a grating with a zeroth-order diffraction efficiency of 76% and a first-order diffraction efficiency of 11.5%, the external light extraction efficiency can reach up to 80% with an output power of more than 1200 mW and a tuning bandwidth of 3.6 nm. When a grating with a first-order diffraction efficiency of 58.5% and a zeroth-order diffraction efficiency of 28.6% is used, the threshold current is reduced by 46% at the central Fabry-Perot resonance wavelength. Moreover, a tuning bandwidth of 8.3 nm ranging from 442.2 nm to 450.5 nm with an output power of more than 500 mW is achieved. Besides, we also find that the high ruling density is helpful in obtaining narrow lasing linewidth, especially for the EC laser system injected with low current. By using a grating with a ruling density of 2400 grooves/mm, the spectral linewidth of the EC laser can be narrowed to be 0.02 nm with an operating current of 300 mA. As the injection current is increased, the lasing linewidth is little affected by the ruling density of the grating due to the broadened feedback spectrum by the flattening of gain spectrum. The results above shed light on the improvement of the performance of EC lasers by selecting appropriate parameters for the grating.

High-power broadly tunable grating-coupled external cavity laser in green region.

A broadly tunable grating-coupled external cavity laser system in the green region is demonstrated by employing a commercially available broad-area green laser diode. A simple Littrow-type external cavity configuration was adopted, and two gratings with different diffraction efficiencies were used as the light feedback elements. When a grating with the first-order diffraction efficiency of 50% and the zeroth-order diffraction efficiency of 31% was used, a tuning bandwidth of 11.0 nm with an output power near 400 mW was achieved. When a grating with the first-order diffraction efficiency of 10% and the zeroth-order diffraction efficiency of 78% was used, a tuning bandwidth of 5.0 nm with an output power near 750 mW was achieved. Meanwhile, the spectral linewidth was narrowed significantly down to 0.08-0.18 nm from the free-running linewidth of 2.81 nm due to the external mode selection effect. Such high-power broadly tunable green EC lasers are important for second harmonic generation.

Improve the Performance of Mechanoelectrical Transduction of Ionic Polymer-Metal Composites Based on Ordered Nafion Nanofibres by Electrospinning.

An ionic polymer⁻metal composite (IPMC) is a kind of soft material. The applications of IPMC in actuators, environmental sensing, and energy harvesting are currently increasing rapidly. In this study, an ordered Nafion nanofibre mat prepared by electrospinning was used to investigate the characteristics of the mechanoelectrical transduction of IPMC. The morphologies of the Nafion nanofibre mat were characterized. The proton conductivity, ion exchange capacities, and water uptake potential of the Nafion nanofibre mat were compared to traditional IPMC, respectively. A novel mechanism of Nafion nanofibre IPMC was designed and the open circuit voltage and short circuit current were measured. The maximum voltage value reached 100 mv. The output power was 3.63 nw and the power density was up to 42.4 µW/Kg under the load resistance. The Nafion nanofibre mat demonstrates excellent mechanoelectrcical transduction behavior compared to traditional IPMC and could be used for the development of self-powered devices in the future.

Modified-Nutrition Index is a Significant Prognostic Factor for the Overall Survival of the Nasopharyngeal Carcinoma Patients who Undergo Intensity-modulated Radiotherapy.

PURPOSE: To explore whether the modified-nutrition index (m-NI) is a prognostic factor for the overall survival (OS) in nasopharyngeal carcinoma (NPC) patients who undergo intensity-modulated radiotherapy (IMRT). METHODS: Clinical data were prospectively collected from NPC patients who underwent IMRT at our hospital between October 2008 and December 2014. The patient nutritional status before radiotherapy was evaluated using the m-NI, based on eight nutrition indicators including body mass index, arm muscle circumference, albumin, total lymphocyte count, red blood cell count, hemoglobin, serum pre-albumin, and transferrin. The independent prognostic value of m-NI for the OS was evaluated. RESULTS: A total of 323 patients (229 males, 94 females) were included in this study, and the follow-up rate was 99.7% (322/323). The 1-, 3-, and 5-yr OS rates between malnutrition and normal nutrition groups by using the m-NI were 93.0% vs. 96.9%, 76.4% vs. 82.8%, and 61.8% vs. 77.1%, respectively. A regression analysis showed that the m-NI was the significant prognostic value for the OS in NPC. CONCLUSIONS: The m-NI before radiotherapy is a significant prognostic factor for the OS in NPC patients. Further validation of our instrument is needed in other NPC patients.

Prognostic significance of pretreated serum lactate dehydrogenase level in nasopharyngeal carcinoma among Chinese population: A meta-analysis.

BACKGROUND: A large number of studies have investigated the prognostic value of pretreated lactate dehydrogenase (LDH) level in nasopharyngeal carcinoma (NPC) patients while the role of it was inconsistent and inconclusive. Hence, the aim of the current study was to conduct a meta-analysis of all published studies to quantify the prognostic impact of pretreated serum LDH in NPC for Chinese population. OBJECTIVES: The aim of the current study was to conduct a meta-analysis of all published studies to quantify the prognostic impact of pretreated serum lactate dehydrogenase (LDH) in nasopharyngeal carcinoma (NPC) for Chinese population. METHODS: The PubMed, Medline, Embase, and Web of Science databases were searched for studies that assessed survival outcome and LDH in NPC. Overall survival (OS) was the primary survival outcome. Distant metastasis-free survival (DMFS) and disease-free survival (DFS) were secondary outcomes. The pooled hazard ratios (HRs), associated with 95% confidence intervals (95% CIs), were combined to calculate overall effects. The Cochran Q and I statistics were used to assess heterogeneity. When apparent heterogeneity was observed, sensitivity and meta-regression analyses were performed to explore its origin. RESULTS: Sixteen studies, which included 14,803 patients, were enrolled in the current meta-analysis to yield statistics. Overall, the pooled HR for OS in 11 eligible studies with high LDH level was 1.79 (95% CI = 1.47-2.12), and the pooled HR for DMFS in 9 eligible studies with high LDH level was 1.85 (95% CI = 1.48-2.22). Meanwhile, the pooled HR for DFS in 5 eligible studies with high LDH level was 1.63 (95% CI = 1.34-1.91). Egger test and funnel plots revealed that the publication bias in the current meta-analysis was insignificant. CONCLUSIONS: The present meta-analysis demonstrated that high pretreated LDH level is significantly associated with poorer OS, DMFS, and DFS, suggesting that pretreated LDH could sever as a prognostic factor in NPC among Chinese population.

Effect of chemoradiotherapy on nutrition status of patients with nasopharyngeal cancer.

We aimed to assess the effect of chemoradiotherapy on the nutritional status of patients with nasopharyngeal cancer (NPC) and to detect the risk factors for poor nutrition status in NPC patients after radiotherapy. A total of 104 NPC patients participated in this clinical observational study. Psychological distress and nutritional indicators were measured prior to chemoradiotherapy. During the course of radiation therapy, side effect symptoms were assessed weekly. At the end of radiotherapy, nutritional indicators were measured again. Logistic regression was used to identify the risk factors for poor nutritional status after radiotherapy. The values of the 9 nutritional indicators were significantly lower after radiotherapy (P < 0.001) than the initial values before treatment. After radiotherapy, 20.19% of patients had more than 10% weight loss. At a significance level of α = 0.05, the risk factors for poor nutritional status were old age (P = 0.042), female gender (P < 0.001), late stage of the disease (P = 0.013), depression (P = 0.024), high side effect score (P = 0.007), and moderate nutritional status before radiotherapy (P = 0.015). Radiotherapy affects the nutritional status of NPC patients. To prevent malnutrition during radiotherapy, nutritional assessment and intervention should be an integral part of treatment.

Association between absolute volumes of lung spared from low-dose irradiation and radiation-induced lung injury after intensity-modulated radiotherapy in lung cancer: a retrospective analysis.

The aim of this study was to investigate the association between absolute volumes of lung spared from low-dose irradiation and radiation-induced lung injury (RILI) after intensity-modulated radiotherapy (IMRT) for lung cancer. The normal lung relative volumes receiving greater than 5, 10, 20 and 30 Gy (V5-30) mean lung dose (MLD), and absolute volumes spared from greater than 5, 10, 20 and 30 Gy (AVS5-30) for the bilateral and ipsilateral lungs of 83 patients were recorded. Any association of clinical factors and dose-volume parameters with Grade ≥2 RILI was analyzed. The median follow-up was 12.3 months; 18 (21.7%) cases of Grade 2 RILI, seven (8.4%) of Grade 3 and two (2.4%) of Grade 4 were observed. Univariate analysis revealed the located lobe of the primary tumor. V5, V10, V20, MLD of the ipsilateral lung, V5, V10, V20, V30 and MLD of the bilateral lung, and AVS5 and AVS10 of the ipsilateral lung were associated with Grade ≥2 RILI (P < 0.05). Multivariate analysis indicated AVS5 of the ipsilateral lung was prognostic for Grade ≥2 RILI (P = 0.010, OR = 0.272, 95% CI: 0.102-0.729). Receiver operating characteristic curves indicated Grade ≥2 RILI could be predicted using AVS5 of the ipsilateral lung (area under curve, 0.668; cutoff value, 564.9 cm(3); sensitivity, 60.7%; specificity, 70.4%). The incidence of Grade ≥2 RILI was significantly lower with AVS5 of the ipsilateral lung ≥564.9 cm(3) than with AVS5 < 564.9 cm(3) (P = 0.008). Low-dose irradiation relative volumes and MLD of the bilateral or ipsilateral lung were associated with Grade ≥2 RILI, and AVS5 of the ipsilateral lung was prognostic for Grade ≥2 RILI for lung cancer after IMRT.

Icaritin synergistically enhances the radiosensitivity of 4T1 breast cancer cells.

Icaritin (ICT) is a hydrolytic form of icariin isolated from plants of the genus Epimedium. This study was to investigate the radiosensitization effect of icaritin and its possible underlying mechanism using murine 4T1 breast cancer cells. The combination of Icaritin at 3 µM or 6 µM with 6 or 8 Gy of ionizing radiation (IR) in the clonogenic assay yielded an ER (enhancement ratio) of 1.18 or 1.28, CI (combination index) of 0.38 or 0.19 and DRI (dose reducing index) of 2.51 or 5.07, respectively. These strongly suggest that Icaritin exerted a synergistic killing (?) effect with radiation on the tumor cells. This effect might relate with bioactivities of ICT: 1) exert an anti-proliferative effect in a dose- and time-dependent manner, which is different from IR killing effect but likely work together with the IR effect; 2) suppress the IR-induced activation of two survival paths, ERK1/2 and AKT; 3) induce the G2/M blockage, enhancing IR killing effect; and 4) synergize with IR to enhance cell apoptosis. In addition, ICT suppressed angiogenesis in chick embryo chorioallantoic membrane (CAM) assay. Taken together, ICT is a new radiosensitizer and can enhance anti-cancer effect of IR or other therapies.

Amifostine acts upon mitochondria to stimulate growth of bone marrow and regulate cytokines.

Amifostine is a first-line cytoprotective drug used to prevent radiotherapy-induced or chemotherapy-induced injuries. However, its mechanism of action is not well understood. In this study, freshly harvested bone marrow cells were treated with amifostine and analyzed with a series of mitochondrial indices. In vitro results showed that bone marrow cells treated with amifostine 0.5 h before irradiation (0.5 Gy) experienced several benefits, as compared to vehicle controls, including (1) reduced reactive oxygen species levels, which reduced the production of free radicals; (2) better preservation of mitochondria, as indicated by MitoTracker-positive staining and the increased intensity of staining; (3) reduced apoptosis, as demonstrated by Annexin V staining; and (4) a better proliferation rate, as illustrated by MTT assay. Our in vitro studies showed that amifostine-treated mice exhibited (1) higher ATP production; (2) reduced plasma IL-2 levels, suppressing the immune response triggered by radiotoxicity; and (3) enhanced radiation-induced production of granulocyte colony-stimulating factor. All of these processes benefit recovery from radiation-induced damage.