[Technology specification of bedside hypertonic saline-contrast electrical impedance tomography of lung perfusion and clinical application].

Bedside hypertonic saline-contrast electrical impedance tomography (EIT) method for lung perfusion evaluation has several advantages of bedside, simple, noninvasive and radiation-free. For a long time, EIT perfusion image of hypertonic saline was mostly limited to animal experiments, and related clinical research is in the ascendant. This technical specification for clinical application is reached based on our previous researches, review of literatures in this field. The purpose of this technical specification is to facilitate the unified and standardized use of hypertonic saline-contrast EIT technology for regional lung perfusion, to evaluate the safety and quality control of the technology, and to unify the results.

[Clinical value of early bedside ultrasound measurement of quadriceps femoris in diagnosis of ICU-acquired weakness].

Objective: To explore the correlation between quadriceps thickness (thickness of rectus femoris and vastus intermedius), cross-sectional area (cross-sectional area of the rectus femoris) and the strength score of the Medical Research Council (MRC) in critically ill patients, and to explore the changes in the length of hospital stay in the intensive care unit (ICU), and to determine the diagnostic value of muscle changes in the ICU-acquired weakness (ICU-AW). Methods: Patients admitted to the Department of Critical Care Medicine from March to October in 2019 who were expected to stay for more than five days were enrolled in this study. The cross-sectional area of the rectus femoris, the thickness of the rectus femoris, the thickness of the vastus intermedius on the first day of the ICU (D(1)), day 3 (D(3)), and day 5 (D(5)), day 7 (D(7)), out of ICU (D(ICU)), and the MRC muscle strength scores on the day of out of ICU prospectively were collected in all the patients, and the correlation and the regularity of quadriceps changes were analyzed. MRC>48 points on the day of dismiss of ICU were used as the standard for the diagnosis of ICU-AW, and the relationship between muscle changes of the quadriceps and ICU-AW was analyzed. The t test or the Mann-Whitney U test was used for data analysis. Results: A total of 45 patients were included, including 25 males and 20 females, aged (58±10) years. The rectus femoris cross-sectional area, rectus femoris thickness, and vastus intermedius thickness decreased with the length of ICU hospital stay. The cross-sectional area, thickness of the rectus femoris muscle, and the vastus intermedius thickness were positively correlated with the MRC score (r=0.452, 0.411, 0.402, all P<0.05), and the changes were all negatively correlated with the MRC score (r=-0.682, -0.740, -0.734, all P<0.05). On the 3rd day after ICU admission, the best cutoff value of rectus muscle cross-sectional area atrophy rate for discrimination of ICU-AW was 6.0%, with a sensitivity of 66.7% and a specificity of 77.8%; on the 5th day, the best cutoff value of rectus femoris thickness atrophy rate was 14.5%, with a sensitivity of 77.8% and a specificity of 66.7%; on the 7th day, the best cutoff value of vastus intermedius thickness atrophy rate was 19.9%, with a sensitivity of 70.6% and a specificity of 87.5%. Conclusion: Bedside ultrasound measurement of the quadriceps femoris cross-sectional area and thickness has certain diagnostic value for ICU-AW, and can identify patients with ICU-AW early.

[Relationship between social support, resilience, self-esteem and post-traumatic stress disorder in intensive care unit nurses].

Objective: To investigate the correlation between social support, resilience, self-esteem and post-traumatic stress disorder (PTSD) in intensive care unit (ICU) nurses. Methods: A total of 717 ICU nurses from 24 provinces conducted these questionnaires (Chinese version of Impact of Event Scale-Revised(IES-R), Social Support Rate Score(SSRS), Cannor-Davidson Resilience(CD-RISC) and Self-Esteem Scale(SES)). There were 101 males and 616 females, with an average age of (30±5) years. With the aim to investigate PTSD impact factors, the ICU nurses were divided into the PTSD positive group (IES-R>35) and PTSD negative group (IES-R<35). The correlation between IES-R and other scales were analyzed with linear regression analysis. Results: In this investigation, 414 nurses were screened with PTSD and 303 nurses without. IES-R score was negatively correlated with SSRS, CD-RISC and SES (r=-0.275, -0.202, -0.709, all P<0.05). Multivariate regression analysis showed that ICU clinical experience was an independent risk factor for PTSD, and SES Score, SSRS Score and physical health status were protective factors. SES partially mediated the association of SSRS with IES-R, and the mediating effect were 51.5%. The area under characteristic curve (ROC) showed that SSRS score, CD-RISC score, SES score and PTSD risk score Logit (P) for prediction of PTSD was 0.629, 0.604, 0.831 and 0.848, respectively. Conclusions: Social support, physical health and self-esteem are protective factors of PTSD, while ICU clinical experience is a risk factor. SES partially mediated the association of SSRS with IES-R.

[Predictive value of white blood cell, procalcitonin and high-sensitivity C-reactive protein for the bloodstream infection in the super-elderly critically-ill patients].

Objective: To investigate the ability of white blood cell (WBC), procalcitonin (PCT) and high-sensitivity C-reactive protein (hs-CRP) in the super-elderly patients with bloodstream infection. Methods: It was a retrospective study. A total of 77 patients (≥85 years) admitted to the ICU of Peking Union Medical College Hospital from June, 2016 to December, 2017 were enrolled. The patients included 67 males and 10 females, with an age of 85-105 years and the average age was (92±5) years. According to the results of blood culture, patients were divided into positive blood culture group (n=50) and negative blood culture group (n=27). The data which obeyed normal distribution were compared with single sample t test between the two groups. Results: There was no significant difference in WBC level between the positive blood culture group and the negative blood culture group[12.4(7.8, 36.6)×10(9)/L vs 10.7(8.5, 18.7)×10(9)/L, U=0.109, P=0.124]. Compared to the positive blood culture group, the PCT level [2.6(0.8, 7.4)µg/L vs 1.5(0.6, 5.3)µg/L, U=3.015, P=0.004] and hs-CRP level [119(62, 220) mg/vs 54 (24, 80) mg/L, U=7.791, P<0.001] were significantly higher in the negative blood culture group. The ROC analysis showed that the area under the curves (AUC) of WBC, PCT and hs-CRP was 0.704(95%CI: 0.586-0.822, P<0.01), 0.896(95%CI: 0.829-0.964, P<0.01) and 0.864(95%CI: 0.778-0.949, P<0.01), respectively. The best cutoff value of PCT for discrimination of positive blood culture was 0.44 µg/L, which resulted in a sensitivity of 70.0% and a specificity of 92.6%. The best cutoff value of hs-CRP was 50.35 mg/L, which resulted in a sensitivity of 62.0% and a specificity of 88.9%. Conclusion: Compared to WBC, both PCT and hs-CRP have a better ability to predict bloodstream infection in the Super-elderly patients.

[Using peripheral perfusion index and venous-to-arterial CO(2) difference/arterial-central venous O(2) difference ratio to assess lactate clearance in septic patients after resuscitation].

Objective: The relationship of venous-to-arterial CO(2) difference(Pv-aCO(2))/arterial-central venous O(2) difference (Ca-vO(2)) ratio, peripheral perfusion index(PI) and lactate clearance(LC) were investigated during resuscitation in septic patients. And, the meaning of the combination PI and Pv-aCO(2)/Ca-vO(2) ratio to interpret incoherence of lactate clear was explored. Methods: The patients with sepsis were prospectively observed, who admitted to critically care medicine department of Peking Union Medical College Hospital. The hemodynamic parameters, simultaneous arterial and central venous blood gas analysis and PI were obtained at the enrollment (T0) and 8 hours (T8) during resuscitation. The lactate clearance was defined as 8h-LC≥10% and non-lactate clearance was defined as 8h-LC ≤ 10%. Additionally, the patients were divided as three sub-groups according to the PI value at T8: the normalized PI group with PI≥1.4,the mild impaired PI with 1.4

[The relationship between arterial blood lactate clearance, prognosis and myocardial damage in patients with septic shock after early goal-directed therapy].

Objective: To evaluate the prognostic value of arterial blood lactate clearance based on central venous oxygen saturation and perfusion index in patients with septic shock related myocardial injury after early goal-directed therapy. Methods: One hundred and fifty-seven patients with septic shock after early resuscitation were enrolled from August 2013 to July 2016 in ICU at Peking Union Medical College Hospital. Parameters indicating early resuscitation included central venous pressure (CVP) 8-12 mmHg (1 mmHg=0.133 kPa),mean arterial pressure (MAP) >65 mmHg, central venous oxygen saturation(ScvO(2))>70% and urine volume (UO) >0.5ml·kg(-1)·h(-1) and arterial blood lactate (Lac) >2 mmoL/L.Patients were divided into group A [ScvO(2)>80% and perfusion index (PI)>1.4], group B(ScvO(2)>80% and PI<1.4),group C(ScvO(2)<80% and PI>1.4),group D(ScvO(2)<80% and PI<1.4).Hemodynamic parameters and tissue perfusion indexes at 2 hours(T2),4 hours(T4) and 6 hours(T6) after early resuscitation and troponin I which indicated myocardial damage, on day 1 2 3 in ICU were recorded. Results: ⑴Lac clearance in group C was the quickest, which was 34.57% (21.44%, 44.20%) , 58.33% (30.19%, 70.79%) , 71.43% (53.75%, 82.79%) at T2, T4, T6 respectively.⑵The maximal incidence of myocardial damage was in group B(85.0%) and the lowest in group A (45.7%) on day 1 in ICU.Whereas on day 2, group C showed the lowest incidence of myocardial damage (29.3%) and group B the highest(70.0%). On day 3,the proportion of elevated troponin I in group B was 70.0%, which was significantly higher than that of group B (29.3%,P<0.008).⑶Logistic regression analysis suggested that the rate of Lac clearance at T4 in group B was related to the incidence of myocardial damage on day 2 and 3 in ICU. Conclusions: The combination of PI and ScvO(2) as a resuscitation target in patients with septic shock facilitates Lac clearance as the goal of resuscitation.The rate of arterial Lac clearance based on ScvO(2) and PI is correlated with myocardial injury in patients with septic shock after early goal-directed therapy.

[The clinical significance of microcirculation and oxygen metabolism evaluation in acute kidney injury assessment in patients with septic shock after resuscitation].

Objective: To evaluate the value of microcirculation and oxygen metabolism evaluation (MicrOME) in acute kidney injury(AKI) evaluation in patients with septic shock after resuscitation. Methods: Consecutive patients with septic shock after resuscitation and mechanical ventilation were enrolled from October 2016 to February 2017 in ICU at Peking Union Medical College Hospital.Patients were divided into 3 groups based on 10 min transcutaneous oxygen challenge test transcutaneous partial pressure of oxygen(PtcO(2))and venoarterial pressure of carbon dioxide difference (Pv-aCO(2)) /arteriovenous O(2) content difference (Ca-vO(2)) by blood gas analysis, i.e. group A [ΔPtcO(2)>66 mmHg(1 mmHg=0.133 kPa) and Pv-aCO(2)/Ca-vO(2)≤1.23], group B (ΔPtcO(2)≤66 mmHg), group C (ΔPtcO(2)>66 mmHg and Pv-aCO(2)/Ca-vO(2)>1.23). Heart rate,mean arterial pressure,central venous pressure,noradrenaline dose,lactate,Pv-aCO(2),Ca-vO(2), lactate clearance, central venous oxygen saturation(ScvO(2)) and liquid equilibrium were assessed after resuscitation.AKI staging based on Kidney Disease Global Improving Outcomes (KDIGO) clinical practice guideline was analyzed. The predictive value of lactate, ScvO(2), Pv-aCO(2)/Ca-vO(2) to progression of AKI after resuscitation was determined using receiver operating characteristic(ROC)curve analysis. Results: A total of 49 septic shock patients were enrolled including 30 males and 19 females with mean age of (61.10±17.10)years old.There were 19 patients in group A,21 patients in group B, and 9 patients in group C. Acute physiology and chronic health evaluation Ⅱ score was 20.92±7.19 and sequential organ failure assessment score 12.02±3.28. There were 4 patients with AKI and 1 progressed in group A, 11 patients with AKI and 2 progressed in group B, 6 patients with AKI and 4 progressed in group C. The cutoff value of Pv-aCO(2)/Ca-vO(2) was equal or more than 2.20 for predicting progression of AKI, resulting in a sensitivity of 85.7% and a specificity of 73.8%. Conclusion: MicrOME is a significant parameter to predict the progression of AKI in patients with septic shock after resuscitation. Pv-aCO(2)/Ca-vO(2) is also a good predictive factor.

[Comparison of invasive and non-invasive blood pressure in critically ill patients].

Objective: To investigate the difference of invasive and noninvasive blood pressure in systolic, diastolic and mean blood pressure (SBP, DBP and MAP) levels in critically ill patients. Methods: A total of 197 critically ill patients were enrolled in the intensive care unit of Peking Union Medical College Hospital in this prospective observative study. There were 113 males and 84 females with a mean age of (59±17) years. With Pearson correlation and Bland-Altman analysis, the difference and agreement of invasive and noninvasive blood pressure in SBP, DBP and MAP levels were investigated. Results: Invasive blood pressure monitoring was significantly correlated with noninvasive blood pressure (the correlation coefficients of SBP, DBP and MAP was 0.908, 0.861 and 0.888, respectively, all P<0.001). The mean bias and 95% confidence interval (CI) in SBP(invasive)-SBP(noninvasive), DBP(invasive)-DBP(noninvasive), MAP(invasive)-MAP(noninvasive) respectively was as following: SBP (14.5±11.9) mmHg (-8.8-37.8 mmHg); DBP (1.0±7.2) mmHg(-13.2-15.2 mmHg); MAP (10.5±8.3) mmHg (-5.9-26.8 mmHg). Moreover, there was a significant positive correlation between the bias of SBP(invasive)-SBP(noninvasive) and the value of SBP; when the SBP(invasive)≥143 mmHg was used to predict a value of bias≥20 mmHg, the sensitivity was 72.4% and specificity was 81.3%, and the area under the receiver operating characteristic curve was 0.808 (95% CI: 0.745-0.870). Conclusions: There is a good agreement between invasive and noninvasive blood pressure in critically ill patients, the bias of invasive-noninvasive blood pressure measurement is positively correlated to the value of blood pressure.

[Experts consensus on the management of the right heart function in critically ill patients].

To establish the experts consensus on the right heart function management in critically ill patients. The panel of consensus was composed of 30 experts in critical care medicine who are all members of Critical Hemodynamic Therapy Collaboration Group (CHTC Group). Each statement was assessed based on the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) principle. Then the Delphi method was adopted by 52 experts to reassess all the statements. (1) Right heart function is prone to be affected in critically illness, which will result in a auto-exaggerated vicious cycle. (2) Right heart function management is a key step of the hemodynamic therapy in critically ill patients. (3) Fluid resuscitation means the process of fluid therapy through rapid adjustment of intravascular volume aiming to improve tissue perfusion. Reversed fluid resuscitation means reducing volume. (4) The right ventricle afterload should be taken into consideration when using stroke volume variation (SVV) or pulse pressure variation (PPV) to assess fluid responsiveness.(5)Volume overload alone could lead to septal displacement and damage the diastolic function of the left ventricle. (6) The Starling curve of the right ventricle is not the same as the one applied to the left ventricle,the judgement of the different states for the right ventricle is the key of volume management. (7) The alteration of right heart function has its own characteristics, volume assessment and adjustment is an important part of the treatment of right ventricular dysfunction (8) Right ventricular enlargement is the prerequisite for increased cardiac output during reversed fluid resuscitation; Nonetheless, right heart enlargement does not mandate reversed fluid resuscitation.(9)Increased pulmonary vascular resistance induced by a variety of factors could affect right heart function by obstructing the blood flow. (10) When pulmonary hypertension was detected in clinical scenario, the differentiation of critical care-related pulmonary hypertension should be a priority. (11) Attention should be paid to the change of right heart function before and after implementation of mechanical ventilation and adjustment of ventilator parameter. (12) The pulmonary arterial pressure should be monitored timingly when dealing with critical care-related pulmonary hypertension accompanied with circulatory failure.(13) The elevation of pulmonary aterial pressure should be taken into account in critical patients with acute right heart dysfunction. (14) Prone position ventilation is an important measure to reduce pulmonary vascular resistance when treating acute respiratory distress syndrome patients accompanied with acute cor pulmonale. (15) Attention should be paid to right ventricle-pulmonary artery coupling during the management of right heart function. (16) Right ventricular diastolic function is more prone to be affected in critically ill patients, the application of critical ultrasound is more conducive to quantitative assessment of right ventricular diastolic function. (17) As one of the parameters to assess the filling pressure of right heart, central venous pressure can be used to assess right heart diastolic function. (18). The early and prominent manifestation of non-focal cardiac tamponade is right ventricular diastolic involvement, the elevated right atrial pressure should be noticed. (19) The effect of increased intrathoracic pressure on right heart diastolic function should be valued. (20) Ttricuspid annular plane systolic excursion (TAPSE) is an important parameter that reflects right ventricular systolic function, and it is recommended as a general indicator of critically ill patient. (21) Circulation management with right heart protection as the core strategy is the key point of the treatment of acute respiratory distress syndrome. (22) Right heart function involvement after cardiac surgery is very common and should be highly valued. (23) Right ventricular dysfunction should not be considered as a routine excuse for maintaining higher central venous pressure. (24) When left ventricular dilation, attention should be paid to the effect of left ventricle on right ventricular diastolic function. (25) The impact of left ventricular function should be excluded when the contractility of the right ventricle is decreased. (26) When the right heart load increases acutely, the shunt between the left and right heart should be monitored. (27) Attention should be paid to the increase of central venous pressure caused by right ventricular dysfunction and its influence on microcirculation blood flow. (28) When the vasoactive drugs was used to reduce the pressure of pulmonary circulation, different effects on pulmonary and systemic circulation should be evaluated. (29) Right atrial pressure is an important factor affecting venous return. Attention should be paid to the influence of the pressure composition of the right atrium on the venous return. (30) Attention should be paid to the role of the right ventricle in the acute pulmonary edema. (31) Monitoring the difference between the mean systemic filling pressure and the right atrial pressure is helpful to determine whether the infusion increases the venous return. (32) Venous return resistance is often considered to be a insignificant factor that affects venous return, but attention should be paid to the effect of the specific pathophysiological status, such as intrathoracic hypertension, intra-abdominal hypertension and so on. Consensus can promote right heart function management in critically ill patients, optimize hemodynamic therapy, and even affect prognosis.

Involvement of nNOS in the antinociceptive activity of melatonin in inflammatory pain at the level of sensory neurons.

OBJECTIVE: The efficacy of melatonin as an analgesic agent has been well documented in animals and humans. However, the underlying mechanisms by which melatonin exerts antinociceptive effects on inflammatory pain are poorly understood. Here, we investigated the potential of melatonin to ameliorate inflammatory pain. MATERIALS AND METHODS: In vitro, ND7/23 neurons were treated with capsaicin. We used PCR and Western blot analyses to detect the expression of neuronal nitric oxide synthase (nNOS) in response to melatonin. Orofacial inflammatory pain was induced by 4% formalin administration on the right whisker pad of Sprague Dawley (SD) rats. The analgesic effect of melatonin was evaluated using mechanical threshold analyses. The expression level of nNOS in the trigeminal ganglion (TG) and trigeminal nucleus caudalis (Vc) neurons was assessed by RNAscope and immunohistochemistry. RESULTS: In vitro, capsaicin upregulated the expression of nNOS, which was dose-dependently reversed by melatonin pretreatment (p < 0.001). In a rat model of orofacial inflammatory pain, melatonin pretreatment significantly attenuated mechanical allodynia in both the acute and chronic phases (p < 0.05). Furthermore, melatonin decreased the formalin-evoked elevated nNOS mRNA and protein levels in the TG and Vc neurons in the acute and chronic phases (p < 0.05). CONCLUSIONS: Taken together, these results suggest that nNOS may play an active role in both peripheral and central processing of nociceptive information following orofacial inflammatory pain induction. The regulatory effect of melatonin on nNOS in inflammatory pain may have potential implications for the development of novel analgesic strategies.

Melatonin regulates mitochondrial function and biogenesis during rat dental papilla cell differentiation.

OBJECTIVE: The aim of this study was to investigate the effect of melatonin on mitochondria of dental papilla cells (DPCs) during the odontogenic differentiation process. MATERIALS AND METHODS: Primary DPCs were obtained from the first molar dental papilla of neonatal rats and cultured in osteogenic (OS) or basal medium supplemented with melatonin at different concentrations (0, 1 pM, 0.1 nM, 10 nM, and 1 µM) for differentiation in vitro. Effects of melatonin on differentiation, mitochondrial respiratory function, and mitochondrial biogenesis of DPCs were analyzed. RESULTS: Upon odontogenic induction, Alkaline phosphatase (ALP) activity, dentin sialophosphoprotein (DSPP), and dentin matrix protein (DMP1) expression were significantly enhanced, with a peaked expression at 10 nM of melatonin treatment. During DPCs differentiation, 10 nM melatonin could significantly induce the increase of intracellular Adenosine triphosphate (ATP), the decrease of the oxidized form of nicotinamide adenine dinucleotide (NAD+)/NADH ratio and reactive oxygen species (ROS). The mRNA and protein levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), nuclear respiratory factor 1 (NRF-1), and mitochondrial transcription factor A (TFAM) were significantly increased, and the peak level of expression was found in cells treated with 10 nM of melatonin. Furthermore, the mitochondria DNA (mtDNA) copy number was significantly decreased during DPCs differentiation. CONCLUSIONS: These findings suggest that melatonin can promote the differentiation of rat DPCs and regulate mitochondrial energy metabolism, ROS scavenging, and mitochondrial biogenesis.

Low-level serum miR-24-2 is associated with the progression of colorectal cancer.

BACKGROUND: colorectal cancer (CRC) is the second leading cause of cancer and cancer-related death in the world. Noninvasive biomarkers for early diagnosis of CRC are highly demanded. OBJECTIVE: The up-regulation of specific microRNAs (miRNAs) in serum has been considered a promising biomarker of CRC and miR-24-2 may be a potential biomarker in the diagnosis the progression of CRC. METHODS: Sixty-eighty healthy subjects and 228 CRC patients were divided into six groups: control group, CRC 0, CRC I, CRC II, CRC III, CRC IV and CRC V. Serum level of miR-24-2 was measured by real-time qPCR. Serum lipid profiles and oxidative-related molecules were also measured. RESULTS: Serum levels of miR-24-2 in CRC patients were significantly higher than healthy subjects (p< 0.05). In addition, the expression level of the miR-24-2 was decreased with the progression of CRC and reached the lowest level in CRC V. Spearman Rank Correlation analysis showed that miR-24-2 level was negatively related to the levels of superoxide dismutase (SOD) and reduced glutathione (GSH), aspartate transaminase (AST), alanine transaminase (ALT), cholesterol and triglyceride (p< 0.05). CONCLUSIONS: Serum miR-24-2 is a potential negative biomarker in the diagnosis of the progression of CRC patients and associated with biochemical indices.

Electrophysiological effects of melatonin on rat trigeminal ganglion neurons that participate in nociception in vitro.

OBJECTIVE: Melatonin (MT) is a hormone mainly produced by the pineal gland. It may be involved in the regulation of nociception, the mechanisms of which remain unclear. In the present study, electrophysiological effects of MT on neurons were studied. MATERIALS AND METHODS: The cultured neurons were isolated from Sprague-Dawley rats trigeminal ganglia (TG). The neuron was voltage clamped using the whole cell patch clamp technique. We recorded resting membrane potential, action potential threshold and number, action potential duration and GABA-activated inward currents in the presence of 0.01 µM, 10 µM MT, and in the absence of MT. RESULTS: In the presence of high concentration of MT, the spontaneous action potential disappeared and action potential threshold was significantly increased. GABA-activated inward currents were recorded and blocked by GABAA receptor antagonist, bicuculline, in the majority of TG neurons (91% 40/44). Continuous perfusion of MT could cause a decrease of GABA-activated currents. The inhibiting effect was dose-dependent and irreversible. CONCLUSIONS: The results suggest that MT has several electrophysiological effects on TG neurons, which may be involved in the peripheral mechanisms of orofacial pain.

Downregulation of G3BPs inhibits the growth, migration and invasion of human lung carcinoma H1299 cells by suppressing the Src/FAK-associated signaling pathway.

G3BP is a RasGAP binding protein that is overexpressed in many human cancers. We previously reported that downregulation of G3BP suppressed cell growth and induced apoptosis in HCT116 cells. Here we report that both transient and stable knockdown of G3BP suppressed the growth, migration and invasion capability of human lung carcinoma H1299 cells. Moreover, downregulation of G3BP significantly inhibited the phosphorylation of Src, FAK and ERK, and the levels of NF-κB were also markedly decreased in H1299 cells. Knockdown of G3BP also decreased the expression of matrix metalloproteinase-2 (MMP-2), MMP-9 and plasminogen activator (uPA), and in vivo data demonstrated that downregulation of G3BP markedly inhibited the growth of H1299 tumor xenografts. Together, these data revealed that knockdown of G3BP inhibited the migration and invasion of human lung carcinoma cells through the inhibition of Src, FAK, ERK and NF-κB and decreased levels of MMP-2, MMP-9 and uPA.

Suppression of N-Ras by shRNA-expressing plasmid increases sensitivity of HepG2 cells to vincristine-induced growth inhibition.

Oncogenic ras genes relate to the development of human cancers. In this study, we used a plasmid-mediated short-hairpin RNA (shRNA) targeting N-ras gene to combine with clinical drug vincristine (VCR) for the treatment of human hepatoma cells. Our results showed that anti-N-Ras shRNA expression vector (pCSH1-shNR) knocked down the target mRNA and protein. Higher efficacy on growth inhibition was observed when pCSH1-shNR was combined with VCR. This synergistic effect was associated with abrogation of VCR-induced overexpressions of P-glycoprotein and multidrug resistance-associated protein 1 by pCSH1-shNR through downregulations of N-Ras and total Ras. Western blot analysis showed that pCSH1-shNR-induced downregulations of N-Ras and total Ras were potentiated by VCR. Following Ras downregulation, phosphorylations of ERK1/2 and Akt were dramatically inhibited by combinatory treatment. The data showed that pCSH1-shNR-induced inhibition of nuclear factor-kappaB was enhanced by VCR. In addition, the combination of pCSH1-shNR and VCR synergistically inhibited the growth of human hepatoma HepG2 in vivo. Our findings suggested that combination of gene-specific therapeutics and appropriate chemotherapeutic agents might be a promising approach for the treatment of human hepatocellular carcinoma.