Serine/threonine-protein kinase D2-mediated phosphorylation of DSG2 threonine 730 promotes esophageal squamous cell carcinoma progression

Desmoglein-2 (DSG2) is a transmembrane glycoprotein belonging to the desmosomal cadherin family, which mediates cell-cell junctions; regulates cell proliferation, migration, and invasion; and promotes tumor development and metastasis. We previously showed serum DSG2 to be a potential biomarker for the diagnosis of esophageal squamous cell carcinoma (ESCC), although the significance and underlying molecular mechanisms were not identified. Here, we found that DSG2 was increased in ESCC tissues compared with adjacent tissues. In addition, we demonstrated that DSG2 promoted ESCC cell migration and invasion. Furthermore, using interactome analysis, we identified serine/threonine-protein kinase D2 (PRKD2) as a novel DSG2 kinase that mediates the phosphorylation of DSG2 at threonine 730 (T730). Functionally, DSG2 promoted ESCC cell migration and invasion dependent on DSG2-T730 phosphorylation. Mechanistically, DSG2 T730 phosphorylation activated EGFR, Src, AKT, and ERK signaling pathways. In addition, DSG2 and PRKD2 were positively correlated with each other, and the overall survival time of ESCC patients with high DSG2 and PRKD2 was shorter than that of patients with low DSG2 and PRKD2 levels. In summary, PRKD2 is a novel DSG2 kinase, and PRKD2-mediated DSG2 T730 phosphorylation promotes ESCC progression. These findings may facilitate the development of future therapeutic agents that target DSG2 and DSG2 phosphorylation. © 2024 The Pathological Society of Great Britain and Ireland.

Serum IGFBP-1 as a promising diagnostic and prognostic biomarker for colorectal cancer

Our previous study showed that levels of circulating insulin-like growth factor binding protein-1 (IGFBP-1) has potential diagnostic value for early-stage upper gastrointestinal cancers. This study aimed to assess whether serum IGFBP-1 is a potential diagnostic and prognostic biomarker for CRC patients. IGFBP-1 mRNA expression profile data of peripheral blood in colorectal cancer (CRC) patients were downloaded and analyzed from Gene Expression Omnibus database. We detected serum IGFBP-1 in 138 CRC patients and 190 normal controls using enzyme-linked immunosorbent assay. Blood IGFBP-1 mRNA levels were higher in CRC patients than those in normal controls (P = 0.027). In addition, serum IGFBP-1 protein levels in the CRC group were significantly higher than those in normal control group (P < 0.0001). Serum IGFBP-1 demonstrated better diagnostic accuracy for all CRC and early-stage CRC, respectively, when compared with carcinoembryonic antigen (CEA), carbohydrate antigen19-9 (CA 19-9) or the combination of CEA and CA19-9. Furthermore, Cox multivariate analysis revealed that serum IGFBP-1 was an independent prognostic factor for OS (HR = 2.043, P = 0.045). Our study demonstrated that serum IGFBP-1 might be a potential biomarker for the diagnosis and prognosis of CRC. In addition, the nomogram might be helpful to predict the prognosis of CRC.

Secreted proteins encoded by super enhancer-driven genes could be promising biomarkers for early detection of esophageal squamous cell carcinoma

BACKGROUND

Early detection of cancer remains an unmet need in clinical practice, and high diagnostic sensitivity and specificity biomarkers are urgently required. Here, we attempted to identify secreted proteins encoded by super-enhancer (SE)-driven genes as diagnostic biomarkers for esophageal squamous cell carcinoma (ESCC).

METHODS

We conducted an integrative analysis of multiple data sets including ChIP-seq data, secretome data, CCLE data and GEO data to screen secreted proteins encoded by SE-driven genes. Using ELISA, we further identified up-regulated secreted proteins through a small size of clinical samples and verified in a multi-centre validation stage (345 in test cohort and 231 in validation cohort). Receiver operating characteristic curves were used to calculate diagnostic accuracy. Artificial intelligence (AI) method named gradient boosting machine (GBM) were applied for model construction to enhance diagnostic accuracy.

RESULTS

Serum EFNA1 and MMP13 were identified, and showed significantly higher levels in ESCC patients compared to normal controls. An integrated Five-Biomarker Panel (iFBPanel) established by combining EFNA1, MMP13, carcino-embryonic antigen, Cyfra21-1 and squmaous cell carcinoma antigen had AUCs of 0.881 and 0.880 for ESCC in test and validation cohorts, respectively. Importantly, the iFBPanel also exhibited good performance in detecting early-stage ESCC patients (0.872 and 0.864). Furthermore, the iFBPanel was further empowered by AI technology which showed excellent diagnostic performance in early-stage ESCC (0.927 and 0.907).

CONCLUSIONS

Our study suggested that serum EFNA1 and MMP13 could potentially assist ESCC detection, and provided an easy-to-use detection model that might help the diagnosis of early-stage ESCC.

A Nomogram Based on Nutrition-Related Indicators and Computed Tomography Imaging Features for Predicting Preoperative Lymph Node Metastasis in Curatively Resected Esophagogastric Junction Adenocarcinoma

BACKGROUNDS

Preoperative noninvasive tools to predict pretreatment lymph node metastasis (PLNM) status accurately for esophagogastric junction adenocarcinoma (EJA) are few. Thus, the authors aimed to construct a nomogram for predicting PLNM in curatively resected EJA.

METHODS

This study enrolled 638 EJA patients who received curative surgery resection and divided them randomly (7:3) into training and validation groups. For nomogram construction, 26 candidate parameters involving 21 preoperative clinical laboratory blood nutrition-related indicators, computed tomography (CT)-reported tumor size, CT-reported PLNM, gender, age, and body mass index were screened.

RESULTS

In the training group, Lasso regression included nine nutrition-related blood indicators in the PLNM-prediction nomogram. The PLNM prediction nomogram yielded an area under the receiver operating characteristic (ROC) curve of 0.741 (95 % confidence interval [CI], 0.697-0.781), which was better than that of the CT-reported PLNM (0.635; 95% CI 0.588-0.680; p < 0.0001). Application of the nomogram in the validation cohort still gave good discrimination (0.725 [95% CI 0.658-0.785] vs 0.634 [95% CI 0.563-0.700]; p = 0.0042). Good calibration and a net benefit were observed in both groups.

CONCLUSIONS

This study presented a nomogram incorporating preoperative nutrition-related blood indicators and CT imaging features that might be used as a convenient tool to facilitate the preoperative individualized prediction of PLNM for patients with curatively resected EJA.

Nutritional and immune-related indicators-based Nomogram for predicting overall survival of surgical oral tongue squamous cell carcinoma

Oral tongue squamous cell carcinoma (OTSCC) is one of the most aggressive oral tumors. The aim of this study was to establish a nomogram to predict overall survival (OS) of TSCC patients after surgery. 169 TSCC patients who underwent surgical treatments in the Cancer Hospital of Shantou University Medical College were included. A nomogram based on Cox regression analysis results was established and internally validated using bootstrap resampling method. pTNM stage, age and total protein, immunoglobulin G, factor B and red blood cell count were identified as independent prognostic factors to create the nomogram. The Akaike Information Criterion and Bayesian Information Criterion of the nomogram were lower than those of pTNM stage, indicating a better goodness-of-fit of the nomogram for predicting OS. The bootstrap-corrected concordance index of nomogram was higher than that of pTNM stage (0.794 vs. 0.665, p = 0.0008). The nomogram also had a good calibration and improved overall net benefit. Based on the cutoff value obtained from the nomogram, the proposed high-risk group had poorer OS than low-risk group (p < 0.0001). The nomogram based on nutritional and immune-related indicators represents a promising tool for outcome prediction of surgical OTSCC.

A novel nomogram based on clinical blood indicators for prognosis prediction in curatively resected esophagogastric junction adenocarcinoma patients

Background: The incidence of esophagogastric junction adenocarcinoma (EJA) patients was increasing but their prognoses were poor. Blood-based predictive biomarkers were associated with prognosis. This study was to build a nomogram based on preoperative clinical laboratory blood biomarkers for predicting prognosis in curatively resected EJA. Methods: Curatively resected EJA patients, recruited between 2003 and 2017 in the Cancer Hospital of Shantou University Medical College, were divided chronologically into the training (n=465) and validation groups (n=289). Fifty markers, involving sociodemographic characteristics and preoperative clinical laboratory blood indicators, were screened for nomogram construction. Independent predictive factors were selected using Cox regression analysis and then were combined to build a nomogram to predict overall survival (OS). Results: Composed of 12 factors, including age, body mass index, platelets, aspartate aminotransferase-to-alanine transaminase ratio, alkaline phosphatase, albumin, uric acid, IgA, IgG, complement C3, complement factor B and systemic immune-inflammation index, we constructed a novel nomogram for OS prediction. In the training group, when combined with TNM system, it acquired a C-index of 0.71, better than using TNM system only (C-index: 0.62, p < 0.001). When applied in the validation group, the combined C-index was 0.70, also better than using TNM system (C-index: 0.62, p < 0.001). Calibration curves exhibited that the nomogram-predicted probabilities of 5-year OS were both in consistency with the actual 5-year OS in both groups. Kaplan-Meier analysis exhibited that patients with higher nomogram scores contained poorer 5-year OS than those with lower scores (p < 0.0001). Conclusions: In conclusion, the novel nomogram built based on preoperative blood indicators might be the potential prognosis prediction model of curatively resected EJA.

PCMT1 has Potential Prognostic Value and Promotes Cell Growth and Motility in Breast Cancer.. [DOI: 10.21203/rs.3.rs-2349165/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Breast cancer (BC) is one of the frequently diagnosed cancers, and the leading cause of cancer-related death among women worldwide. The roles of protein L-isoaspartate (D-aspartate) O-methyltransferase (PCMT1) in human cancer have been exploring, but the clinical significance and biological function of PCMT1 in BC are not yet clear. In this study, based on the TCGA-BRCA data set, the results showed that high expression of PCMT1 gene was significantly correlated with shorter overall survival (OS), disease specific survival (DSS) and progress free suvival (PFS) of BC patients. Utilizing the immunohistochemical assay, we found that PCMT1 protein was located in the cytoplasm of BC cells, and PCMT1 expression was only obviously correlated with progesterone receptor expression of patients (p < 0.05). Survival analysis showed that PCMT1 protein high-expression was an independent unfavorable prognostic factor for BC patients. The in vitro experiments revealed that PCMT1 could regulate growth, migration and invasion capacity of MCF-7 cell, and modulate the expression of AKT/GSK3β/mTOR signaling pathway, EMT and cell cycle-associated protein. In conclusion, PCMT1 was a potential unfavorable prognostic biomarker for BC patient and might influence the AKT/GSK3β/mTOR signaling pathway to regulate the growth and motility of MCF-7 cell.

Serum insulin-like growth factor binding protein-3 as a potential biomarker for diagnosis and prognosis of oesophageal squamous cell carcinoma

BACKGROUND

Insulin-like growth factor binding protein-3 (IGFBP3) has been reported to be related to the risk of some cancers. Here we focussed on serum IGFBP3 as a possible biomarker of diagnosis and prognosis for oesophageal squamous carcinoma (ESCC).

METHODS

Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum IGFBP3 level in the training cohort including 136 ESCC patients and 119 normal controls and the validation cohort with 55 ESCC patients and 42 normal controls. The receiver operating characteristics curve (ROC) was used to assess the diagnosis value. Cox proportional hazards model was applied to select factors for survival nomogram construction.

RESULTS

Serum IGFBP3 levels were significantly lower in early-stage ESCC or ESCC patients than those in normal controls (p < .05). The specificity and sensitivity of serum IGFBP3 for the diagnosis of ESCC were 95.80% and 50.00%, respectively, with the area under the ROC curve (AUC) of 0.788 in the training cohort. Similar results were observed in the validation cohort (88.10%, 38.18%, and 0.710). Importantly, serum IGFBP3 could also differentiate early-stage ESCC from controls (95.80%, 52.54%, 0.777 and 88.10%, 36.36%, 0.695 in training and validation cohorts, respectively). Furthermore, Cox multivariate analysis revealed that serum IGFBP3 was an independent prognostic risk factor (HR = 2.599, p = .002). Lower serum IGFBP3 level was correlated with reduced overall survival (p < .05). Nomogram based on serum IGFBP3, TNM stage, and tumour size improved the prognostic prediction of ESCC with a concordance index of 0.715.

CONCLUSION

We demonstrated that serum IGFBP3 was a potential biomarker of diagnosis and prognosis for ESCC. Meanwhile, the nomogram might help predict the prognosis of ESCC. Key MessageSerum IGFBP3 showed early diagnostic value in oesophageal squamous cell carcinoma with independent cohort validation. Moreover, serum IGFBP3 was identified as an independent prognostic risk factor, which was used to construct a nomogram with improved prognosis ability in oesophageal squamous cell carcinoma.

Serum insulin-like growth factor binding protein 3 as a promising diagnostic and prognostic biomarker in esophagogastric junction adenocarcinoma

BACKGROUND

Esophagogastric junction adenocarcinoma (EJA) lacks serum biomarkers to assist in diagnosis and prognosis. Here, we aimed to evaluate the diagnostic and prognostic value of serum insulin-like growth factor binding protein 3 (IGFBP3) in EJA patients.

METHODS

320 participants were recruited from November 2016 to January 2020, who were randomly divided into a training cohort (112 normal controls and 102 EJA patients including 24 early-stage patients) and a validation cohort (56 normal controls and 50 EJA patients including 12 early-stage patients). We used receiver operating characteristics curve (ROC) to evaluate diagnostic value. The predictive performance of the nomogram was evaluated by the concordance index (C-index).

RESULTS

Serum IGFBP3 levels were significantly lower in early-stage EJA or EJA patients than those in controls (P < 0.01). Measurement of serum IGFBP3 demonstrated an area under curve of 0.819, specificity 90.18% and sensitivity 43.14% in training cohort. Similar results were observed in validation cohort (0.804, 87.50%, 42.00%). Importantly, serum IGFBP3 had a satisfactory diagnostic value for early-stage EJA (0.822, 90.18%, 45.83% and 0.811, 84.48%, 50.00% in training and validation cohorts, respectively). Furthermore, survival analysis demonstrated that lower serum IGFBP3 level was related to poor prognosis (P < 0.05). Cox multivariate analysis revealed that serum IGFBP3 was an independent prognostic factor (HR = 0.468, P = 0.005). Compared with TNM stage, a nomogram based on serum IGFBP3, tumor size and TNM stage indicated an improved C-index in prognostic prediction (0.625 vs. 0.735, P = 0.001).

CONCLUSIONS

We found that serum IGFBP3 was a potential diagnostic and prognostic marker of EJA. Meanwhile, the nomogram might predict the prognosis of EJA more accurately and efficiently.

Nomogram constructed by immunological and inflammatory indicators for predicting prognosis of patients with esophageal squamous cell carcinoma treated with neoadjuvant chemoradiotherapy plus surgery

OBJECTIVES

At present, esophageal squamous cell carcinoma (ESCC) patients accepting neoadjuvant chemoradiotherapy (nCRT) plus surgery lack corresponding prognostic indicators. This study aimed to construct a prognostic prediction model for ESCC patients undergoing nCRT and surgery based on immune and inflammation-related indicators.

METHODS

We retrospectively analyzed the levels of serum immune- and inflammation-related indicators of ESCC patients before receiving nCRT plus surgery in the training cohort (99 patients) and validation cohort (67 patients), which were collected from 2007 to 2020. Univariate and multivariate Cox survival analyses were conducted to evaluate the indicators to set up a nomogram associated with the patients' overall survival (OS). The prediction accuracy and discriminative ability of the nomogram were measured by the concordance index (C-index), decision curve, calibration curve, integrated discrimination improvement (IDI), and net reclassification improvement (NRI).

RESULTS

Univariate and multivariate Cox analyses demonstrated that immune globin A (IgA) and C-reactive protein (CRP) were independent risk factors. A nomogram based on IgA, CRP, and cTNM stage was established for predicted OS in the training cohort and validated in the validation cohort. The C-index of the nomogram was 0.820 (95% CI: 0.705-0.934), which was higher than that of the cTNM stage (0.655 (95% CI: 0.546-0.764), p < 0.05) in the training cohort, and similar results were observed in the validation cohort (0.832 (95% CI: 0.760-0.903 vs 0.635 (95% CI: 0.509-0.757), p < 0.001). Furthermore, the prediction accuracy and net benefit of the nomogram verified by the calibration curve, decision curve, NRI, and IDI were satisfactory in the training and validation cohorts.

CONCLUSION

The newly constructed nomogram concluding serum IgA, CRP, and cTNM stage might be helpful in the prognosis prediction for ESCC patients receiving nCRT plus surgery.

Serum DSG2 as a potential biomarker for diagnosis of esophageal squamous cell carcinoma and esophagogastric junction adenocarcinoma

BACKGROUND

Exploration of serum biomarkers for early detection of upper gastrointestinal cancer is required. Here, we aimed to evaluate the diagnostic potential of serum desmoglein-2 (DSG2) in patients with esophageal squamous cell carcinoma (ESCC) and esophagogastric junction adenocarcinoma (EJA).

METHODS

Serum DSG2 levels were measured by enzyme-linked immunosorbent assay (ELISA) in 459 participants including 151 patients with ESCC, 96 with EJA, and 212 healthy controls. Receiver operating characteristic (ROC) curves were used to evaluate diagnostic accuracy.

RESULTS

Levels of serum DSG2 were significantly higher in patients with ESCC and EJA than those in healthy controls (P<0.001). Detection of serum DSG2 demonstrated an area under the ROC curve (AUC) value of 0.724, sensitivity of 38.1%, and specificity of 84.8% for the diagnosis of ESCC in the training cohort, and AUC 0.736, sensitivity 58.2%, and specificity 84.7% in the validation cohort. For diagnosis of EJA, measurement of DSG2 provided a sensitivity of 29.2%, a specificity of 90.2%, and AUC of 0.698. Similar results were observed for the diagnosis of early-stage ESCC (AUC 0.715 and 0.722, sensitivity 36.3 and 50%, and specificity 84.8 and 84.7%, for training and validation cohorts, respectively) and early-stage EJA (AUC 0.704, sensitivity 44.4%, and specificity 86.9%). Analysis of clinical data indicated that DSG2 levels were significantly associated with patient age and histological grade in ESCC (P<0.05).

CONCLUSION

Serum DSG2 may be a diagnostic biomarker for ESCC and EJA.

EFNA1 in gastrointestinal cancer: Expression, regulation and clinical significance

Ephrin-A1 is a protein that in humans is encoded by the EFNA1 gene. The ephrins and EPH-related receptors comprise the largest subfamily of receptor protein-tyrosine kinases which play an indispensable role in normal growth and development or in the pathophysiology of various tumors. The role of EFNA1 in tumorigenesis and development is complex and depends on the cell type and microenvironment which in turn affect the expression of EFNA1. This article reviews the expression, prognostic value, regulation and clinical significance of EFNA1 in gastrointestinal tumors.

Clinical Laboratory Blood Biomarker-Based Nomograms for Prediction of Lymph Node Metastasis and Prognosis in Resectable Esophagogastric Junction Adenocarcinoma: A Retrospective Diagnostic Study.. [DOI: 10.21203/rs.3.rs-1383267/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background Esophagogastric junction adenocarcinoma (EJA) lacks blood-based predictive biomarkers for lymph node status and prognosis. We aimed to build nomograms with the preoperative blood biomarkers to predict lymph node metastasis (LNM) and prognosis in resectable EJA. Methods In this study, EJA patients who underwent surgery were collected from the Cancer Hospital of Shantou University Medical College between January 2010 and December 2017. The patients were divided into training cohort (n = 465) and validation cohort (n = 289) chronologically. 52 candidate biomarkers for nomogram construction included sociodemographic data and preoperative clinical laboratory blood baseline data. Lasso regression was used to build LNM prediction nomogram (LNM nomogram). Univariate and multivariate Cox regression analysis was applied to select factors for overall survival prediction nomogram (OS nomogram). Results As a result, for predicting LNM, the LNM nomogram containing seven biomarkers showed good discrimination and calibration ability, with C-indexes of 0.684 and 0.630 in the training and validation cohorts, respectively. Moreover, the OS nomogram for survival prediction composed of 12 factors yielded C-indexes of 0.652 and 0.663 in the training and validation cohorts, respectively. Kaplan-Meier survival analysis showed patients with high OS nomogram scores had worse 5-year OS than those with low scores (training cohort: 59.6% vs. 26.2%; validation cohort: 58.6% vs. 38.6%; all p < 0.0001). Conclusions In conclusion, these two nomograms constructed based on the clinical laboratory blood biomarkers are potential prediction models for lymph node status and survival of resectable EJA.

Nomogram based on clinical characteristics and serological inflammation markers to predict overall survival of oral tongue squamous cell carcinoma patient after surgery

BACKGROUND

Oral tongue squamous cell carcinoma (OTSCC) is a prevalent malignant disease that is characterized by high rates of metastasis and postoperative recurrence. The aim of this study was to establish a nomogram to predict the outcome of OTSCC patients after surgery.

METHODS

We retrospectively analyzed 169 OTSCC patients who underwent treatments in the Cancer Hospital of Shantou University Medical College from 2008 to 2019. The Cox regression analysis was performed to determine the independent prognostic factors associated with patient's overall survival (OS). A nomogram based on these prognostic factors was established and internally validated using a bootstrap resampling method.

RESULTS

Multivariate Cox regression analysis revealed the independent prognostic factors for OS were TNM stage, age, lymphocyte-to-monocyte ratio and immunoglobulin G, all of which were identified to create the nomogram. The Akaike Information Criterion and Bayesian Information Criterion of the nomogram were lower than those of TNM stage (292.222 vs. 305.480; 298.444 vs. 307.036, respectively), indicating a better goodness-of-fit of the nomogram for predicting OS. The bootstrap-corrected of concordance index (C-index) of nomogram was 0.784 (95% CI 0.708-0.860), which was higher than that of TNM stage (0.685, 95% CI 0.603-0.767, P = 0.017). The results of time-dependent C-index for OS also showed that the nomogram had a better discriminative ability than that of TNM stage. The calibration curves of the nomogram showed good consistency between the probabilities and observed values. The decision curve analysis also revealed the potential clinical usefulness of the nomogram. Based on the cutoff value obtained from the nomogram, the proposed high-risk group had poorer OS than low-risk group (P < 0.0001).

CONCLUSIONS

The nomogram based on clinical characteristics and serological inflammation markers might be useful for outcome prediction of OTSCC patient.

Nomogram Based On Clinical Characteristics and Serological Inflammation Markers To Predict Overall Survival of Tongue Squamous Cell Carcinoma Patient After Surgery.. [DOI: 10.21203/rs.3.rs-900581/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background Tongue squamous cell carcinoma (TSCC) is a prevalent malignant disease that is characterized by high rates of metastasis and postoperative recurrence. The aim of this study was to establish a nomogram to predict the outcome of TSCC patients after surgery. Methods We retrospectively analyzed 169 TSCC patients who underwent treatments in the Cancer Hospital of Shantou University Medical College from 2008 to 2019. The Cox regression analysis was performed to determine the independent prognostic factors associated with patient’s overall survival (OS). A nomogram based on these prognostic factors was established and internally validated using a bootstrap resampling method. Results Multivariate Cox regression analysis revealed the independent prognostic factors for OS were TNM stage, age, lymphocyte-to-monocyte ratio and immunoglobulin G, all of which were identified to create the nomogram. The Akaike Information Criterion and Bayesian Information Criterion of the nomogram were lower than those of TNM stage (292.222 vs. 305.480; 298.444 vs. 307.036, respectively), indicating a better goodness-of-fit of the nomogram for predicting OS. The bootstrap-corrected of concordance index (C-index) of nomogram was 0.784 (95% CI: 0.708–0.860), which was higher than that of TNM stage (0.685, 95% CI: 0.603–0.767, P = 0.017). The results of time-dependent C-index for OS also showed that the nomogram had a better discriminative ability than that of TNM stage. The calibration curves of the nomogram showed good consistency between the probabilities and observed values. The decision curve analysis also revealed the potential clinical usefulness of the nomogram. Based on the cutoff value obtained from the nomogram, the proposed high-risk group had poorer OS than low-risk group (P < 0.0001). Conclusions The nomogram based on clinical characteristics and serological inflammation markers might be useful for outcome prediction of TSCC patient.

[Preoperative video distraction alleviates separation anxiety and improves induction compliance of preschool children: a randomized controlled clinical trial]

Objective: To explore the effect of video distraction on preoperative separation anxiety and induction compliance of preschool children receiving strabismus surgery under general anesthesia. Methods: In this prospective trial, 80 children aged 3 to 6 years scheduled for strabismus surgery under inhalation anesthesia were randomly allocated to one of two groups, a control group and a video distraction group, with 40 cases in each group. Children in the video distraction group continuously watched videos from waiting in the holding area, separating with parents, entering the operating room and induction of anesthesia, while children in the control group didn't watch videos during the same process. The modified Yale Preoperative Anxiety Scale (mYPAS) of children were recorded upon arriving at the holding area(T₁)and separating with parents(T₂). Induction Compliance Checklist (ICC) score was recorded when the anesthesia induction was performed. The emergence time, the occurrence rate of adverse events in post-anesthesia care unit (PACU) including nausea and vomiting, laryngospasm, severe cough, hypoxemia and sinus bradycardia, incidence of postoperative adverse reactions such as pain, dizziness, nausea and vomiting and lethargy, the parents' satisfaction of anesthesia were also assessed. Results: There were no significant difference in mYPAS score and the proportion of mYPAS score>30 between 2 groups at T₁ (all P>0.05). At T₂, the mYPAS score and the proportion of mYPAS score>30 in video distraction group were (34.41±13.23) and 52.50%, which were lower than those in control group (50.64±20.96, 87.50%) with statistically significant difference (all P<0.05). The ICC score of video distraction group was lower than that of the control group, which was (1.83±2.26) vs (4.03±2.99), and the difference was statistically significant (P<0.05). The proportion of children with ICC score=0 in video distraction group was 37.50%, which was higher than that in the control group (12.50%), while the proportion of children with ICC score=4-10 was lower than that of the control group, which was 17.50% vs 45.00%, and the difference was statistically significant (P<0.05). No significant intergroup differences were observed in emergence time, incidence of adverse events in PACU, and incidence of postoperative adverse reactions (P>0.05). The parents' satisfaction of anesthesia in the video distraction group was (9.23±0.89), which was higher than that in the control group (8.63±1.23), with statistically significant (P<0.05). Conclusion: Preoperative video distraction alleviates separation anxiety, improves induction compliance of preschool children receiving strabismus surgery under general anesthesia, and increases the parents' satisfaction of anesthesia.

Serum CYR61 as a potential biomarker for the diagnosis of esophagogastric junction tumor

BACKGROUND

Esophagogastric junction tumor (EGJ) is a rare but fatal disease with a rapid rising incidence worldwide in the late 20 years, and it lacks a convenient and safe method for diagnosis. The present study aimed to evaluate the potential of serum CYR61 as a biomarker for the diagnosis of EGJ tumor.

METHODS

Enzyme-linked immunosorbent assay (ELISA) was used to estimate CYR61 levels in sera of 152 EGJ tumor patients and 137 normal controls. Receiver operating characteristics (ROC) was carried out to evaluate the diagnostic accuracy. The Mann-Whitney's U test was used to compare the difference of serum levels of CYR61 between groups. And chi-square tests were employed to estimate the correlation of the positive rate of serum CYR61 between/among subgroups.

RESULTS

Serum CYR61 levels were statistically lower in EGJ tumor and early-stage EGJ tumor patients than those in normal controls (P<0.0001). The sensitivity, specificity and the area under the curve (AUC) of this biomarker in EGJ tumor were 88.2%, 43.8% and 0.691, respectively, and those for early stage of EGJ tumor were 80.0%, 66.4% and 0.722, respectively. Analyses showed that there was no correlation between the clinical data and the levels of CYR61 (P>0.05).

CONCLUSION

The present study showed that CYR61 might be a potential biomarker to assist the diagnosis of EGJ tumor.

Nomogram based on nutritional and inflammatory indicators for survival prediction of small cell carcinoma of the esophagus

OBJECTIVES

Small cell carcinoma of the esophagus (SCCE) is a rare type of esophageal cancer, and the parameters for prediction of SCCE outcome are unclear. This study aimed to construct a nomogram to predict the outcome of SCCE.

METHODS

Patients who underwent treatments at the Sun Yat-Sen University Cancer Center were recruited and divided randomly into training and validation cohorts (61 and 32 patients, respectively). A Cox regression analysis was utilized to identify independent prognostic factors to establish a nomogram and predict overall survival (OS) and disease-free survival (DFS).

RESULTS

Information on pretreatment nutritional candidate hemoglobin and inflammation-related neutrophil-to-lymphocyte ratio and platelet count were entered into the nomogram. In the training cohort, the concordance index of the nomogram for OS was 0.728, higher than that obtained by tumor/node/metastasis staging (0.614; P = 0.014). A significant difference was observed in the nomogram for DFS (0.668 vs tumor/node/metastasis stage: 0.616; P = 0.014). Similar results were found in the validation group. The decision curve analysis, net reclassification improvement, and integrated discrimination improvement showed moderate improvement of the nomogram in predicting survival. Based on the cut point calculated according to the constructed nomogram, the high-risk group had poorer OS and DFS than the low-risk group in both cohorts (all P < 0.05). Moreover, the DFS of patients receiving surgery in the high-risk group was better than that of patients receiving single radiation therapy or chemotherapy (P = 0.0111).

CONCLUSIONS

A nomogram based on nutrition- and inflammation-related indicators was developed to predict the survival of patients with SCCE.

A Panel of Tumor-associated Autoantibodies for the Detection of Early-stage Breast Cancer

We previously found a panel of autoantibodies against multiple tumor-associated antigens (BMI-1, HSP70, MMP-7, NY-ESO-1, p53 and PRDX6) that might facilitate early detection of esophagogastric junction adenocarcinoma and esophageal squamous cell carcinoma. Here we aimed at assessing the diagnostic performance of these autoantibodies in breast cancer patients. Enzyme-linked immunosorbent assay was applied to detect sera autoantibodies in 123 breast cancer patients and 123 age-matched normal controls. We adopted logistic regression analysis to identify optimized autoantibody biomarkers for diagnosis and receiver-operating characteristics to analyze diagnostic efficiency. Five of six autoantibodies, BMI-1, HSP70, NY-ESO-1, p53 and PRDX6 demonstrated significantly elevated serum levels in breast cancer compared to normal controls. An optimized panel composed of autoantibodies to BMI-1, HSP70, NY-ESO-1 and p53 showed an area under the curve (AUC) of 0.819 (95% CI 0.766-0.873), 63.4% sensitivity and 90.2% specificity for diagnosing breast cancer. Moreover, this autoantibody panel could differentiate patients with early stage breast cancer from normal controls, with AUC of 0.805 (95% CI 0.743-0.886), 59.6% sensitivity and 90.2% specificity. Our findings indicated that the panel of autoantibodies to BMI-1, HSP70, NY-ESO-1 and p53 as serum biomarkers have the potential to help detect early stage breast cancer.

A Prognostic Model Based on Clinicopathological Features and Inflammation- and Nutrition-Related Indicators Predicts Overall Survival in Surgical Patients With Tongue Squamous Cell Carcinoma

Objectives: It is reported that inflammation- and nutrition-related indicators have a prognostic impact on multiple cancers. Here we aimed to identify a prognostic nomogram model for prediction of overall survival (OS) in surgical patients with tongue squamous cell carcinoma (TSCC). Methods: The retrospective data of 172 TSCC patients were charted from the Cancer Hospital of Shantou University Medical College between 2008 and 2019. A Cox regression analysis was performed to determine prognostic factors to establish a nomogram and predict OS. The predictive accuracy of the model was analyzed by the calibration curves and the concordance index (C-index). The difference of OS was analyzed by Kaplan-Meier survival analysis. Results: Multivariate analysis showed age, tumor node metastasis (TNM) stage, red blood cell, platelets, and platelet-to-lymphocyte ratio were independent prognostic factors for OS, which were used to build the prognostic nomogram model. The C-index of the model for OS was 0.794 (95% CI = 0.729-0.860), which was higher than that of TNM stage 0.685 (95% CI = 0.605-0.765). In addition, decision curve analysis also showed the nomogram model had improved predictive accuracy and discriminatory performance for OS, compared to the TNM stage. According to the prognostic model risk score, patients in the high-risk subgroup had a lower 5-year OS rate than that in a low-risk subgroup (23% vs 49%, P < .0001). Conclusions: The nomogram model based on clinicopathological features inflammation- and nutrition-related indicators represents a promising tool that might complement the TNM stage in the prognosis of TSCC.

Serum Insulin-Like Growth Factor Binding Protein 7 as a Potential Biomarker in the Diagnosis and Prognosis of Esophagogastric Junction Adenocarcinoma

BACKGROUND/AIMS

Esophagogastric junction adenocarcinoma (EJA) is a malignant tumor associated with high morbidity and has attracted increasing attention due to a rising incidence and low survival rate. Pathological biopsy is the gold standard for diagnosis, but noninvasive and effective tests are lacking, resulting in diagnoses at advanced stages. This study explored the diagnostic value of insulin-like growth factor binding protein 7 (IGFBP7) in EJA.

METHODS

A total of 120 EJA patients and 88 normal controls were recruited, and their serum levels of IGFBP7 were measured by enzymelinked immunosorbent assay. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic value, and Pearson chi-square analysis was used to evaluate the correlation between IGFBP7 and clinical parameters. Kaplan- Meier survival analysis was carried out to assess the effect of IGFBP7 on overall survival (OS).

RESULTS

The levels of IGFBP7 were higher in both early- and late-stage EJA patients than in normal controls (p<0.001). The area under the ROC curve for EJA patients was 0.794 (95% confidence interval [CI], 0.733 to 0.854), with a cutoff value of 2.716 ng/mL, a sensitivity of 63.3% (95% CI, 54.0% to 71.8%) and a specificity of 90.9% (95% CI, 82.4% to 95.7%). For the diagnosis of early-stage EJA, the same cutoff value and specificity were obtained, but the sensitivity of IGFBP7 was 54.3% (95% CI, 36.9% to 70.8%). Patients with low IGFBP7 protein expression had lower OS than those with high expression (p=0.034). The multivariate analysis showed that IGFBP7 is an independent prognostic factor for EJA (p=0.011).

CONCLUSIONS

Serum IGFBP7 acts as a potential diagnostic and prognostic marker for EJA.

Blood-based biomarkers for early detection of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor of the digestive system worldwide, especially in China. Due to the lack of effective early detection methods, ESCC patients often present at an advanced stage at the time of diagnosis, which seriously affects the prognosis of patients. At present, early detection of ESCC mainly depends on invasive and expensive endoscopy and histopathological biopsy. Therefore, there is an unmet need for a non-invasive method to detect ESCC in the early stages. With the emergence of a large class of non-invasive diagnostic tools, serum tumor markers have attracted much attention because of their potential for detection of early tumors. Therefore, the identification of serum tumor markers for early detection of ESCC is undoubtedly one of the most effective ways to achieve early diagnosis and treatment of ESCC. This article reviews the recent advances in the discovery of blood-based ESCC biomarkers, and discusses the origins, clinical applications, and technical challenges of clinical validation of various types of biomarkers.

The Diagnostic Value of Serum L1CAM in Patients With Colorectal Cancer

OBJECTIVE

Colorectal cancer is one of the most important malignant cancer in the world with high incidence and mortality. Some studies have found that the expression of low serum L1 cell adhesion molecule is associated with poor prognosis in some malignancies. It is suggested that L1 cell adhesion molecule is a candidate serum marker for certain tumors. However, the relationship between serum L1 cell adhesion molecule and colorectal cancer, especially about the diagnostic value, is rarely reported. Therefore, this study aimed to evaluate the diagnostic potential of serum L1 cell adhesion molecule in patients with colorectal cancer.

METHODS

Enzyme-linked immunosorbent assay was carried out to detect L1 cell adhesion molecule level in sera of 229 patients with colorectal cancer and 145 normal controls. Receiver operating characteristic curves were employed to calculate the accuracy of diagnosis.

RESULTS

The levels of serum L1 cell adhesion molecule in the colorectal cancer group were significantly lower than that in normal controls (P < .05). In the normal group, the area under the receiver operating characteristic curve (area under the curve) of all colorectal cancer was 0.781 (95% confidence interval: 0.734-0.828) and early-stage colorectal cancer was 0.764 (95% confidence interval: 0.705-0.823). With optimized cutoff of 17.760 ng/mL, L1 cell adhesion molecule showed certain diagnostic value with specificity of 90.3% and sensitivities of 43.2% and 36.2% in colorectal cancer and early-stage colorectal cancer, respectively. Clinical data analysis showed that the levels of L1 cell adhesion molecule were significantly correlated with gender (P < .05) and early and late stages (P < .05). Furthermore, when compared with carcinoembryonic antigen, serum L1 cell adhesion molecule had significantly improved diagnostic accuracy for both colorectal cancer and early-stage colorectal cancer.

CONCLUSIONS

Our study demonstrated that serum L1 cell adhesion molecule might be served as a potential biomarker for the diagnosis of colorectal cancer.

ApoB/ApoA-1 Ratio as a Novel Prognostic Predictor in Patients With Primary Small Cell Carcinoma of the Esophagus

Background and Aim: Primary small cell carcinoma of the esophagus (SCCE) is a rarely aggressive disease characterized by rapid progression, widespread metastasis, and poor prognosis. This study was aimed to evaluate the prognostic significance of serum lipids for overall survival (OS) in SCCE patients. Methods: We retrospectively analyzed SCCE patients in a training cohort (61 patients) and validated them in a validation cohort (27 patients). These cases were collected from Sun Yat-sen University Cancer Center from 2006 to 2017. Univariate and multivariate Cox survival analyses were performed to determine serum lipids as prognostic factors associated with the patient's OS. Time-dependent receiver operating characteristics (ROC) were used to compare predictive power of independent prognostic factors. The predictive accuracy and discriminative ability of the prognostic factors were measured by the concordance index (C-index) and decision curve, and were compared with the TNM stage system. Results: On multivariate analysis of the training cohort, independent factors for survival were gender, BAR (ApoB/ApoA-1) and TNM stage. The area under the curve (AUC) of BAR+TNM stage in the training cohort was higher than that of TNM stage for OS, and similar result was observed in the validation cohort. The c-index of BAR+TNM stage for predicting the OS was 0.655 (95% CI = 0.571-0.740), which was higher than that of TNM stage [0.614 (95% CI = 0.530-0.698)] in the training cohort. In the validation cohort, the C-index of the BAR+TNM stage for predicting OS was also higher than that of the TNM stage [0.688 (95% CI: 0.570~0.806) vs. (0.512; 95% CI: 0.392~0.632)]. In addition, decision curve analysis also showed that the predictive accuracy of BAR+TNM stage for OS was higher than TNM stage both in the training and the validation cohorts. Conclusions: BAR represents a promising prognostic indicator that might complement TNM stage in the prognosis of SCCE, and that warrant further assessment in large SCCE patient cohort.

Circulating Levels of L1-cell Adhesion Molecule as a Serum Biomarker for Early Detection of Gastric Cancer and Esophagogastric Junction Adenocarcinoma

Background: Low serum L1 cell adhesion molecule (L1CAM) has been found in several malignant tumors. Here, we aimed to evaluate the diagnostic potential for serum L1CAM in patients with gastric cancers (GC) and esophagogastric junction adenocarcinoma (EJA). Methods: Enzyme-linked immunosorbent assay (ELISA) was carried out to detect L1CAM level in sera of 148 GC patients, 59 EJA patients and 148 healthy controls. Receiver operating characteristics (ROC) was employed to evaluate diagnostic accuracy. Results: The concentrations of serum L1CAM were significantly lower in GC and EJA than those in healthy controls (P<0.001). Detection of L1CAM provided a sensitivity of 83.1%, a specificity of 62.2%, and an area under the curve (AUC) of 0.769 (95% CI: 0.715-0.823) in diagnosing GC, and a sensitivity of 66.1%, a specificity of 62.2%, and an AUC of 0.672 (95% CI: 0.590-0.755) in diagnosing EJA. Similar results were observed in the diagnosis of early-stage GC (0.681 (95%CI: 0.596-0.766)) and early-stage EJA (0.674 (95%CI: 0.528-0.820)). Analysis of clinical data showed that the levels of L1CAM were significantly associated with lymph node metastasis in GC (P<0.05). Conclusions: Our study showed that serum L1CAM might be a diagnostic biomarker for GC and EJA.

Serum IGFBP-1 as a potential biomarker for diagnosis of early-stage upper gastrointestinal tumour

BACKGROUND

Early detection would improve upper gastrointestinal cancer prognosis. We aimed to identify serum protein biomarker for the detection of early-stage upper gastrointestinal cancer.

METHODS

We performed a three-tiered study including 2028 participants from three medical centres. First, we applied two different antibody arrays to screen candidate serum proteins that increased in 20 patients with oesophageal squamous cell carcinoma (ESCC) compared with 20 normal controls. We then evaluated the selected protein by enzyme-linked immunosorbent assay in 1064 participants including 731 upper gastrointestinal cancer patients (287 ESCCs, 237 oesophagogastric junction adenocarcinomas (EJAs), and 207 stomach cancers) and 333 normal controls. The diagnostic value of the selected protein was finally validated in two independent cohorts of ESCC patients and controls (n=472 and 452, respectively). The receiver operating characteristic was used to calculate diagnostic accuracy.

FINDINGS

Serum insulin-like growth factor binding protein-1 (IGFBP-1) identified in both antibody arrays showed significantly elevated levels in upper gastrointestinal cancers, compared with normal controls. Serum IGFBP-1 provided high diagnostic accuracy of early-stage ESCC, EJA, stomach and cancer (areas under the curve: 0·898, 0·936 and 0·864, respectively). This protein maintained diagnostic performance for early-stage ESCC in independent cohorts 1 and 2 (0·849 and 0·911, respectively). Additionally, serum levels of IGFBP-1 dropped significantly after surgical resection of primary tumours, compared with the corresponding pre-operative ESCC samples (p < 0·05).

INTERPRETATION

Serum IGFBP-1 represents a promising diagnostic biomarker to detect early-stage upper gastrointestinal cancer.

Diagnostic Value of Serum Insulin-Like Growth Factor Binding Protein 7 (IGFBP7) in Colorectal Cancer

PURPOSE

High serum insulin-like growth factor binding protein-7 (IGFBP-7) has been found in several malignant tumors. Here, we aimed to assess the diagnostic potential of serum IGFBP7 in patients with colorectal cancer (CRC).

PATIENTS AND METHODS

An enzyme-linked immunosorbent assay (ELISA) was performed to detect IGFBP7 level in the serum of 115 CRC patients and 107 healthy controls, and receiver operating characteristics (ROC) was used to evaluate the accuracy of diagnosis.

RESULTS

The levels of serum IGFBP7 were significantly higher in CRC than those in normal controls (P < 0.001). With optimized cutoff of 2.050 ng/mL, IGFBP7 showed certain diagnostic value with specificity of 93.9%, sensitivity of 64.5% and an area under the curve (AUC) of 0.815 (95% CI: 0.754-0.877) in CRC. In early-stage CRC, IGFBP7 provided an AUC of 0.826 (95% CI: 0.757-0.896), a sensitivity of 64.5%, and a specificity of 95.8%. Furthermore, when compared with carcinoembryonic antigen (CEA), the accuracy of serum IGFBP7 in the diagnosis of CRC and early-stage CRC were significantly improved. Analysis of clinical data shows that there are no significant differences between IGFBP7 and clinical factors.

CONCLUSION

Our study suggested that serum IGFBP7 might serve as a potential biomarker for early-stage CRC diagnosis.

[Study of the effects of hydromorphone on emergence agitation of children anesthetized by sevoflurane]

Objective: To observe the effect of hydromorphone on emergence agitation of children anesthetized by Sevoflurane. Methods: One hundred patients without any analgetic, aged 3 to 7 years, ASA Ⅰ-Ⅱ, undergoing strabismus surgery in Beijing Tongren Hospital from March, 2017 to December, 2017 were selected and they were randomly divided into two groups(n=50), H group and F group by random number table. After standardized tidal volume method induction by 8% sevoflurane and oxygen, suiltable laryngeal mask was inserted, and each patient was left spontaneously breathing anesthetized by 2.5%-3.0% sevoflurane.Ten minutes before the surgery, patients in H group were administered a dose of 0.01 mg/kg hydromorphone (diluted to 5 ml with normal saline) by pump control injection in 10 min, whereas patients in F group administered a dose of 1 μg/kg fentanyl in the same way. After the surgery , the patient was sent to postanesthesia care unit. A nurse who was blinded measured the vital signs, pediatric anesthesia emergence delirium(PAED) score, face legs activity cry consolability behavioral pain assessment tool(FLACC) score, the time of opening the eyes and departing from postanesthesia care unit(PACU), and the occurence rates of hypoxemia, swirl or nausea, drowsiness, and other scores. Results: The incidence of emergence agitation(EA) in H group was lower than in F group, whether EA was defined as PAED>10 (18.0% vs 28.0%, P>0.05) or PAED>12(12.0% vs 24.0%, P>0.05), there were not significant differences between them. The ratio of patients whose PAED>15 in F group was 12.0%, while the ratio of H group was 0, there was significant difference between the two groups(P=0.027). The occurrence rates of swirl, glossocoma in H group were 0 and 10.0% while those of F group were all 6.0%, there were no significant differences between the two groups(P>0.05). Conclusions: Comparing with fentanyl, hydromorphone can prevent the occurrence rate of EA of the children anesthetized by sevoflurane equally, even decrease the occurrence rate of the severe EA more observably, and reduce postoperation pain more significantly with less occurrence rate of swirl or nausea. Glossocoma need be paid attention to when HM is administered.

[Behavior change of a primipara with cesarean section during early postpartum period]

The focus of this study was to understand the process of behavior change in a cesarean section primipara during her early postpartum period. The study was conducted by the field method with the researcher as the subject's primary nurse. Content analysis was employed to analyze and categorize the 6 sections of the behavioral process record, which were taken down in narrative form by the researcher during the nursing process. Three stages of behavior change were identified: (1) Lack of confidence and uncertainty about self care and newborn care. (2) Actively intending to explore and learn about self care and newborn care. (3) Adjusting caring methods and planning for the future. In this study, the researcher provided information and caring to the subject individually. It assisted the new mother in becoming a competent mother.

Back pain after thoracolumbar fracture treated with long instrumentation and short fusion

The purposes of this retrospective study are to evaluate the degeneration of facets in unfused segments immobilized by Harrington rods and to see how often back pain developed after treatment with this method. Sixty patients with thoracolumbar fracture were treated with the Harrington rod long-fuse short technique. Harrington rods are removed an average of 14 months after initial surgery. Every case showed solid fusion during implant removal exploration. Thereafter, all cases were followed for a minimum of 5 years. Roentgenographic studies and a bone scan were performed to evaluate the degeneration of facet joints. Back pain complaint was found in 11 patients (18.3%). The degeneration of unfused facets was visualized in six patients by roentgenograms. Increased activity in the instrumented spine by bone scan examination also was noted in six patients: three cases were at unfused area, one at a fused area, and two at fused and unfused areas. In conclusion, degeneration in the immobilized and unfused segments after rod long and fused short was rarely seen clinically after long-term follow-up. Back pain was experienced in only 18.3% of the patients and seldom required medication.

[Measurements of the lumbar spinal canal of Chinese by computed tomography]

The study of the lumbar canal sizes in Chinese has not been reported before. Thirty adult patients, aged 20 to 40 years, who sustained thoracolumbar or lumbar fracture-dislocation and needed further computed tomographic (CT) scanning were included in this study. There was no significant back pain or sciatica on these patients before. Measurements of the med-sagittal anteroposterior (A-P) and interpedicular (I-P) diameters of the spinal canals L1 to L5 were requested at the same time during CT scanning. The results show that the lowest normal limits of the A-P and I-P diameters of the lumbar canals in Chinese are 11 mm and 19 mm respectively. The I-P diameters increase progressively from the first to the fifth vertebrae. The A-P diameters, however, are more variable and shortest at L2, L3 and L4 vertebrae.

Arthritis as a manifestation of self-mutilation in childhood

Traumatic arthritis resulting from self-aggression is rarely encountered in children. Differentiation from child abuse and common causes of childhood arthritis is difficult and rests upon a high level of suspicion. We describe a 10-year-old girl with hand deformities associated with joint pain and swelling managed as juvenile rheumatoid arthritis for 3 years. Reevaluation revealed both physical and radiographic evidence of recurrent trauma. Psychiatric assessment confirmed the diagnosis of autoaggression leading to self-mutilation and psychosocial rehabilitation was essential in successful management.

A polypeptide which reverses cap analogue inhibition of cell-free protein synthesis. Purification and binding to capped oligonucleotides

An assay was developed to detect the component which recognizes the methylated 5'-terminus of messenger RNA (cap) during initiation of translation. Globin mRNA translation in a reticulocyte cell-free system was partially inhibited with cap analogues, and protein fractions were added to the system in an attempt to reverse inhibition. Such an activity was detected in the 500 mM KCl extract of rabbit reticulocyte ribosomes. The activity (cap analogue inhibition reversal) was purified 800-fold by precipitation with ammonium sulfate saturation, batchwise chromatography on DEAE-cellulose, centrifugation on sucrose gradients containing 100 and 500 mM KCl, and column chromatography on DEAE-cellulose and phosphocellulose. At some stages multiple peaks of activity were detected. Electrophoretic analysis of the final preparation revealed a single polypeptide of 24,000 daltons, making it likely that it is the same as the cap-binding protein detected by Sonenberg et al. (Sonenberg, N., Morgan, M. A., Merrick, W. C., and Shatkin, A. J. (1978) Proc. Natl. Acad. Sci. U. S. A. 75, 4843-4847), using a cross-linking assay. Direct binding of purified fractions of cap analog inhibition reversal factor to capped oligonucleotides of the form m7Gppp(Np)6-8G[32P]Cp could be demonstrated by both gel filtration on Sephadex G-50 and nitrocellulose membrane filtration. Binding was stimulated by MgCl2 and nucleoside triphosphates. An approximate association constant between oligonucleotide and protein of 3 X 10(8) M-1 was obtained.

Linkage in cultured Chinese hamster cells of two genes, emtB and leuS, involved in protein synthesis and isolation of cell lines with mutations in three linked genes

We have determined via segregation analyses from appropriate hybrids that two genes involved in protein synthesis, one encoding for a ribosomal protein (emtB) and one encoding for leucyl-tRNA synthetase (leuS), cosegregate at a very high frequency and are linked in both Chinese hamster ovary and lung cells. In contrast, the emtA locus, defined by a second complementation group of emetine-resistant mutants which also have alterations affecting protein synthesis and probably the ribosome, is not linked to leuS. In addition, we have determined that a third gene, one that can be altered to give rise to chromate resistance, is syntenic with emtB and leuS. We have selected cell lines with mutations in each of these three linked genes and have shown that the three loci cosegregate at a high frequency. Because the mutations in these three linked genes provide easily distinguishable phenotypes, these cell lines should provide a powerful tool for examining several important questions concerning mitotic recombination in somatic cells.

Translational recognition of the 5'-terminal 7-methylguanosine of globin messenger RNA as a function of ionic strength

The translation of rabbit globin mRNA in cell-free systems derived from either wheat germ or rabbit reticulocyte was studied in the presence of various analogues of the methylated 5' terminus (cap) as a function of ionic strength. Inhibition by these analogues was strongly enhanced by increasing concentrations of KCl, K(OAc), Na(OAc), or NH4(OAc). At appropriate concentrations of K(OAc), both cell-free systems were equally sensitive to inhibition by m7GTP. At 50 mM K(OAc), the reticulocyte system was not sensitive to m7GMP or m7GTP, but at higher concentrations up to 200 mM K(OAc), both nucleotides caused strong inhibition. The compound in m7G5'ppp5'Am was inhibitory at all concentrations of K(OAc) ranging from 50 to 200 mM, although more strongly so at the higher concentrations. Over the same range of nucleotide concentrations, the compounds GMP, GTP, and G5'ppp5'Am were not inhibitors. The mobility on sodium dodecyl sulfate-polyacrylamide electrophoresis of the translation product was that of globin at all K(OAc) concentrations in the presence of m7GTP. Globin mRNA from which the terminal m7GTP group had been removed by chemical treatment (periodate-cyclohexylamine-alkaline phosphatase) or enzymatic treatment (tobacco acid pyrophosphatase-alkaline phosphatase) was translated less efficiently than untreated globin mRNA at higher K(OAc) concentrations, but retained appreciable activity at low K(OAc) concentrations.