Transcriptome analyses of insect cells to facilitate baculovirus-insect expression

The High Five cell line (BTI-TN-5B1-4) isolated from the cabbage looper, Trichoplusia ni is an insect cell line widely used for baculovirus-mediated recombinant protein expression. Despite its widespread application in industry and academic laboratories, the genomic background of this cell line remains unclear. Here we sequenced the transcriptome of High Five cells and assembled 25,234 transcripts. Codon usage analysis showed that High Five cells have a robust codon usage capacity and therefore suit for expressing proteins of both eukaryotic- and prokaryotic-origin. Genes involved in glycosylation were profiled in our study, providing guidance for engineering glycosylated proteins in the insect cells. We also predicted signal peptides for transcripts with high expression abundance in both High Five and Sf21 cell lines, and these results have important implications for optimizing the expression level of some secretory and membrane proteins.

High plasma fibrinogen concentration and platelet count unfavorably impact survival in non-small cell lung cancer patients with brain metastases / 癌症

High expression of fibrinogen and platelets are often observed in non-small cell lung cancer (NSCLC) patients with local regional or distant metastasis. However, the role of these factors remains unclear. The aims of this study were to evaluate the prognostic significance of plasma fibrinogen concentration and platelet count, as well as to determine the overall survival of NSCLC patients with brain metastases. A total of 275 NSCLC patients with brain metastasis were enrolled into this study. Univariate analysis showed that high plasma fibrinogen concentration was associated with age≥65 years (P = 0.011), smoking status (P = 0.009), intracranial symptoms (P = 0.022), clinical T category (P = 0.010), clinical N category (P = 0.003), increased partial thromboplastin time (P < 0.001), and platelet count (P < 0.001). Patients with low plasma fibrinogen concentration demonstrated longer overall survival compared with those with high plasma fibrinogen concentration (median, 17.3 months versus 11.1 months; P≤0.001). A similar result was observed for platelet counts (median, 16.3 months versus 11.4 months; P = 0.004). Multivariate analysis showed that both plasma fibrinogen concentration and platelet count were independent prognostic factors for NSCLC with brain metastases (R2 = 1.698, P < 0.001 and R2 = 1.699, P < 0.001, respectively). Our results suggest that high plasma fibrinogen concentration and platelet count indicate poor prognosis for NSCLC patients with brain metastases. Thus, these two biomarkers might be independent prognostic predictors for this subgroup of NSCLC patients.

Clinicopathological characteristics and prognosis of young esophageal cancer patients / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To compare the clinicopathological features and prognosis of esophageal cancer between young and elderly patients.</p><p><b>METHODS</b>Clinical data of 716 patients with esophageal squamous cell carcinoma undergoing curative operation from January 1990 to December 1998 at the Cancer Center of Sun Yat-sen University were analyzed retrospectively. Clinicopathological features and prognosis of 117 patients aged ≤45 years (young group) at diagnosis were compared with 599 patients aged >45 years (elderly group).</p><p><b>RESULTS</b>Except for tumor stage, there were no significant differences of clinicopathology between the young group and the elderly group (all P>0.05). There were more pathologic stage III cancer in the young group than the elderly group (47.9% vs. 33.6%, P=0.010). The 5-year survival rate (36.0% vs 33.8%) and 10-year survival rate (29.2% vs 25.0%) were not significantly different between the two groups (P=0.418). Multivariate analysis showed that the age was not the independent prognostic factors of esophageal squamous cell carcinoma (P=0.160, RR=1.187, 95%CI:0.935-1.506).</p><p><b>CONCLUSION</b>Young esophageal cancer patients have more advanced tumors than elderly patients. However, the survival is comparable to the elderly.</p>

ABCG2-overexpressing S1-M1-80 cell xenografts in nude mice keep original biochemistry and cell biological properties / 癌症

S1-M1-80 cells, derived from human colon carcinoma S1 cells, are mitoxantrone-selected ABCG2-overexpressing cells and are widely used in in vitro studies of multidrug resistance(MDR). In this study, S1-M1-80 cell xenografts were established to investigate whether the MDR phenotype and cell biological properties were maintained in vivo. Our results showed that the proliferation, cell cycle, and ABCG2 expression level in S1-M1-80 cells were similar to those in cells isolated from S1-M1-80 cell xenografts (named xS1-M1-80 cells). Consistently, xS1-M1-80 cells exhibited high levels of resistance to ABCG2 substrates such as mitoxantrone and topotecan, but remained sensitive to the non-ABCG2 substrate cisplatin. Furthermore, the specific ABCG2 inhibitor Ko143 potently sensitized xS1-M1-80 cells to mitoxantrone and topotecan. These results suggest that S1-M1-80 cell xenografts in nude mice retain their original cytological characteristics at 9 weeks. Thus, this model could serve as a good system for further investigation of ABCG2-mediated MDR.

Survival analysis of 220 patients with completely resected stage-II non-small cell lung cancer / 癌症

<p><b>BACKGROUND AND OBJECTIVE</b>Surgery is the main therapy for patients with stage II non small cell lung cancer (NSCLC), but patients still have an unsatisfactory prognosis even though complete resection is usually possible. Adjuvant chemotherapy provides low rates of clinical benefit as well. We retrospectively analyzed prognostic factors of patients with completely resected stage II NSCLC to find patients with unfavorable factors for proper management.</p><p><b>METHODS</b>Clinical data of 220 patients with complete resections of stage II NSCLC at the Sun Yat sen University Cancer Center between January 1998 and December 2004 were retrospectively analyzed. Cumulative survival was analyzed by the Kaplan Meier method and compared by log rank test. Prognosis was analyzed by the Cox proportional hazards model.</p><p><b>RESULTS</b>The overall 3 and 5 year survival rates were 58.8% and 47.9%, respectively. The 3 and 5 year disease free survival rates were 45.8% and 37.0%, respectively. Of the 220 patients, 86 (39.1%) had recurrence or metastasis. A univariate analysis demonstrated that age (> 55 years), blood type, the presence of symptoms, chest pain, tumor volume (> 20 cm3), total number of removed lymph nodes (> or = 10), number of involved N1 lymph nodes (> or =3 ), total number of removed N2 lymph nodes (> 6), and the ratio of involved N1 lymph nodes (> or = 35%) were significant prognostic factors for 5 year survival. In the multivariate analysis, age (> 55 years), chest pain, tumor volume (> 20 cm3), total number of removed lymph nodes (> or = 10), and number of involved N1 lymph nodes (> or = 3) were independent prognostic factors for 5 year survival.</p><p><b>CONCLUSIONS</b>For patients with completely resectable stage II NSCLC, having > 55 years, presenting chest pain, tumor volumes > 20 cm3, and > or = 3 involved N1 lymph nodes were adverse prognostic factors, and > or = 10 removed lymph nodes was a favorable one. Patients with poor prognoses might be treated by individual adjuvant therapy for better survival.</p>

Impact of the number of resected and involved lymph nodes on the outcome in patients with stage II non-small cell lung cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>The aim of this study was to evaluate if factors associated with dissected lymph nodes affect the outcome of completely resected stage II (T1-2N1) non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>Clinical data of 121 patients with complete resection of stage II NSCLC in Sun Yat-sen University Cancer center from January 1998 to December 2004 were reviewed retrospectively and the effect of factors of dissected lymph nodes on overall survival (OS) and disease-free survival (DFS) of NSCLC was analyzed.</p><p><b>RESULTS</b>The univariate analysis demonstrated that the total number of removed lymph nodes, the number of involved N1 lymph nodes, the ratio of involved N1 lymph nodes and the total number of removed N2 lymph nodes were significant prognostic factors for OS. In the multivariate analysis, the total number of removed lymph nodes and the number of involved N1 lymph nodes were independent prognostic factors for OS. In both of univariate and multivariate analyses, tumor size, the total number of removed lymph nodes and the number of involved N1 lymph nodes were independent prognostic factors for DFS.</p><p><b>CONCLUSION</b>For patients with completely resectable stage II NSCLC, 10 or more lymph nodes should be removed at the surgical resection. Total number of removed lymph nodes >or= 10 is a favorable prognostic factor and involved N1 >or= 3 is an adverse one.</p>

Clinical analysis of 22 cases of esophageal adenosquamous carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>This study was to review the clinical features, diagnosis, treatment, and prognosis of esophageal adenosquamous carcinoma (ASC).</p><p><b>METHODS</b>Clinical data of 22 patients with pathologically confirmed esophageal ASC, treated in the Cancer Center of Sun Yat-sen University from May 1988 to April 2006, were retrospectively analyzed. The survival analysis was performed using Kaplan-Meier method.</p><p><b>RESULTS</b>Of 4208 patients diagnosed as esophageal cancer during the same time in our center, only 22 had esophageal ASC, accounted for 0.52%. The median age of the 22 cases was 60 years (range, 42 to 69 years). Esophageal ASC showed similar clinical symptoms, radiological and endoscopic features to esophageal squamous cell carcinoma (ESCC). Nineteen cases were preoperatively misdiagnosed as ESCC by endoscopic biopsy. Among the 22 patients, 16 were treated by surgery alone, 3 by surgery plus postoperative radiotherapy, and the remaining 3 by radiotherapy, sequential chemoradiotherapy and concurrent chemoradiotherapy, each in one case, respectively. The overall 1-, 3- and 5-year survival rates were 67.6%, 33.8% and 18.1%, respectively, with a median survival time of 24.5 months.</p><p><b>CONCLUSION</b>Esophageal adenosquamous carcinoma is a rare esophageal disease and prone to be misdiagnosed as esophageal squamous cell carcinoma. Initial surgical treatment combined with other therapies is suggested. The prognosis of esophageal adenosquamous carcinoma has not yet been well established.</p>

Risk factor analysis of mediastinal lymph node metastasis in non-small cell lung cancer patients and the strategy of mediastinoscopy prior to surgery / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To discuss the strategy of mediastinoscopy for the evaluation of mediastinal lymph node status (metastasis or not) of non-small cell lung cancer (NSCLC) prior to surgery.</p><p><b>METHODS</b>From October 2000 to June 2007, 152 consecutive NSCLC cases pathologically proven and clinically staged I-III were enrolled in the study. Of the 152 cases, there were 118 males and 34 females. Age ranged 24-79 years old and the median age was 58. All cases underwent CT and mediastinoscopy for the evaluation of mediastinal lymph node status prior to surgery. Compared with the results of final pathology, the positive rate of mediastinoscopy and the prevalence of mediastinal lymph node metastasis were calculated in the NSCLC patients with negative mediastinal or hilar lymph nodes on CT scan (the shortest axis of mediastinal or hilar lymph nodes <1 cm). Clinical characteristics used as predictive factor including sex, age, cancer location, type of pathology, T status, cancer type (central or peripheral), size of mediastinal lymph nodes (the shortest axis <1 cm or >1 cm) on CT scan and serum CEA level were analyzed by univariate and multivariate analysis with Binary logistic regression model to identify risk factors of mediastinal metastasis.</p><p><b>RESULTS</b>The positive rate of mediastinoscopy was 11.6% (8/69) and the prevalence of mediastinal metastasis was 20.1% (14/69) in NSCLC with negative mediastinal or hilar lymph nodes on CT scan respectively. In clinical stage I (cT1-2N0M0) NSCLC the positive rate of mediastinoscopy was 11.3% (7/62), N2 accounting for 6.5% (4/62) and N3 4.8% (3/62), respectively; and the prevalence of mediastinal lymph node metastasis was 19.4% (12/62), N2 ccounting for 14.6% (9/62) and N3 4.8% (3/62), respectively. In the whole group both univariate and multivariate analysis showed that adenocarcinoma or mediastinal lymph nodes > or =1 cm in the shortest axis on CT scan was an independent risk factor to predict mediastinal lymph node metastasis. In NSCLC with negative mediastinal or hilar lymph nodes on CT scan both univariate and multivariate analysis showed that adenocarcinoma was a predictor of mediastinal lymph node metastasis. Conclusion We recommend the policy of routine mediastinoscopy in NSCLC prior to surgery if the mediastinal staging was only based on CT scan. Mediastinal lymph nodes > or =1 cm in the shortest axis on CT scan mandates preoperative mediastinoscopy. Adenocarcinoma also indicates mandatory mediastinoscopy even with negative mediastinal or hilar lymph nodes on CT scan.</p>

Value of mediastinoscopy in preoperative staging of non-small cell lung cancer-based on survival analysis / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the value of mediastinoscopy in preoperative staging of non-small cell lung cancer (NSCLC) based on survival analysis.</p><p><b>METHODS</b>152 cases of potentially operable NSCLC were enrolled in this study. All cases underwent CT scan and mediastinoscopy for assessment of the mediastinal lymph node status before initial treatment. The definitive treatment was decided on the basis of mediastinoscopy and the survival rate was analyzed with a median follow-up of 30.5 months. Survival analysis was conducted by comparing the lymph node status which was determined by final pathology (groups pN0, pN1, pN2, pN3), CT scan (group cN0-1, cN2-3) and mediastinoscopy (group mN0-1, mN2, mN3).</p><p><b>RESULTS</b>The 5-year survival rates in group pN0, pN1, pN2 and pN3 were 61.7%, 75.0%, 32.4% and 16.1%, respectively. Both groups pN0 and pN1 had significantly higher survival rates than those in groups pN2 and pN3 (P < 0.05). There were not significant differences between survival rates in groups cN0-1 and cN2-3 (P = 0.670), while the survival rate in group mN0-1 was significantly higher than that in groups mN2 and mN3 (P < 0.05).</p><p><b>CONCLUSION</b>Mediastinoscopy is of great value in preoperative staging of NSCLC. Not only does it detect lymph node metastasis more precisely but also better predict the prognosis than CT scan.</p>

Prospective comparison of CT versus mediastinoscopy in preoperative evaluation of mediastinal lymph node status in patients with non-small cell lung cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To compare the value of CT and mediastinoscopy in assessment of mediastinal lymph node status in potentially operable non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>From Oct. 2000 to Jun. 2007, 152 consecutive patients with pathologically proven and stage I to approximately III NSCLC were enrolled into the study. Of the 152 cases, there were 118 males and 34 females, with a median age of 58 years (range, 24 to approximately 79 years). Compared with the final pathology, the sensitivity, specificity, positive and negative predictive values and accuracy of CT and mediastinoscopy for preoperative evaluation of mediastinal lymph node status were calculated, respectively. The accuracy and diagnostic efficacy of CT and mediastinoscopy was compared by Pearson chi(2) test and ROC curve, respectively.</p><p><b>RESULTS</b>The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of detection of mediastinal metastasis was 73.8%, 70.1%, 64.9%, 78.2% and 71.7% by CT, respectively, versus 83.1%, 100.0%, 100.0%, 88.8% and 92.8% by mediastinoscopy, respectively. Both the accuracy and diagnostic efficacy of mediastinoscopy were superior to CT (Pearson chi(2) test, P < 0.001; Z test of the areas under the ROC curve, P < 0.001). The complication rate of mediastinoscopy was 4.6%, and the false negative rate was 7.2%.</p><p><b>CONCLUSION</b>Mediastinoscopy is safe and effective in preoperative assessment of mediastinal lymph node status in potentially operable NSCLC, while CT alone is inadequate.</p>

Impact of visceral pleural invasion on the prognosis of stage Ib non-small cell lung cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the impact of visceral pleural invasion (VPI) on prognosis and staging in patients with stage Ib non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>Clinical data of 232 patients with stage Ib NSCLC surgically treated by curative resection between January 1994 and December 2003 was retrospectively reviewed. Histopathological diagnosis was reviewed by an experienced pathologist. According to the tumor size and status of VPI, patients were stratified into three group: group A: tumor > 3 cm and VPI(-); group B: tumor < or = 3 cm and VPI (+); group C: tumor > 3 cm and VPI(+). There were 45 patients in group A, 96 in group B and 91 in group C. Kaplan-Meier method was used for survival analysis. Cox proportional hazards model was used for multivariate analysis.</p><p><b>RESULTS</b>187 (80.6%) patients had visceral plural invasion, while 45 (19.4%) had no. The 5-and 10-year survival rates of patients with VPI were 59.3% and 42.6%, while it was 70.1% and 56.7% for the patients without (P = 0.035), respectively. The 5-year survival rates of patients in group A, B and C were 70.1%, 61.9% and 56.2%; and 10-years survival rates were 56.7%, 50.6% and 35.9%, respectively (P = 0.018). VPI with large size of tumor was revealed by Cox multivariate analysis as an independent prognostic factor (RR = 1.530, 95% CI: 1.132-2.067, P = 0.006).</p><p><b>CONCLUSION</b>A significant difference in survival exists among the stage Ib NSCLC patients who have different T status, the patient with > 3 cm tumor and visceral plural invasion may have the worst prognosis. Further studies are still needed to assess whether it is necessary or not to modify the T2 statue of tumor > 3 cm with visceral plural invasion.</p>

Surgical treatment and prognosis in patients with squamous cell carcinoma of thoracic esophagus / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze the prognostic factors of thoracic esophageal squamous cell carcinoma (ESCC) after esophagectomy.</p><p><b>METHODS</b>The clinicopathologic data of 716 patients with thoracic ESCC from January 1990 to December 1998 were analyzed retrospectively. There were 538 male and 178 female patients aged from 24 to 78 years old with a median of 57 years old. Cumulative survival rate was analyzed by the Kaplan-Meier method and compared by the Log-rank test. COX regression model was used for multivariate prognostic analysis.</p><p><b>RESULTS</b>The overall 1-, 3-, 5- and 10-year survival rates were 82.9%, 44.3%, 34.2% and 25.7% respectively. The 5-year survival rates was 80.0%, 51.2%, 19.7% and 13.3% for stage I, stage IIA, stage IIB and stage III respectively. Of the 716 patients, 151 (21.1%) patients recurred, including 48 (84.2%) of stage IIA recurrence, 22 (91.7%) of stage IIB recurrence and 63 (90.0%) of stage III recurrence occurred within 3 years postoperatively. Univariate analysis revealed that the factors impacting the prognosis were gender, depth of invasion, lymph node metastasis, pathologic stage, number of lymph node metastatic field, differentiation, surgical margin and tumor relapse. Multivariate analysis showed that depth of invasion, lymph node metastasis, pathologic stage and tumor relapse were independently associated to poor prognosis.</p><p><b>CONCLUSIONS</b>Depth of invasion, lymph node metastasis, pathologic stage and tumor relapse are the independent factors of ESCC. Surgery is still the primary treatment for stage I-IIA esophageal cancer; but it is suggested to adopt surgical treatment as primary modality combined with other therapies for stage IIB-III esophageal cancer.</p>

Prognostic effect of mediastinal lymph node dissection in patients with stage I non-small cell lung cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the prognostic effect of mediastinal lymph node dissection in patients with stage I non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>The clinical data of 330 patients with stage I NSCLC who were treated with curative resection from January 1994 to December 2003 were reviewed retrospectively. According to the extent of mediastinal lymph node dissection and the pathology report, the patients were assigned to lung resection combined with mediastinal lymph node dissection (LND) group or with lymph node sampling (LNS) group. The Kaplan-Meier method was used for survival analysis. COX proportional hazards model was used for multivariate analysis.</p><p><b>RESULTS</b>There were 233 (70.6%) male patients and 97 (29.4%) female patients. The median age was 60 years old. Ninety-eight patients were in stage IA and 233 in stage IB. One hundred and forty patents were in group LND and 190 in group LNS. The mean number of removed lymph nodes in group LND and group LNS were (13.3 +/- 4.7) and (5.2 +/- 3.0) (P < 0.01), respectively. The mean of mediastinal lymph node station sampled in group LND and group LNS were (3.7 +/- 0.9) and (1.3 +/- 1.1) (P < 0.01), respectively. The 5-year and 10-year survival rates of patients in group LND were 72.0% and 66.1%, while in group LNS were 65.9% and 43.0% (P < 0.05), respectively. Other prognostic factors included symptom, staging, visceral pleura invasion and tumor size. LND was disclosed as a favourable prognostic factor at COX multivariate analysis, together with absence of symptom at diagnosis.</p><p><b>CONCLUSION</b>As compared with LNS, LND can improve survival in stage I NSCLC.</p>

Experimental study of preventing postoperative stenosis by modifying artificial esophagus in dogs / 中国医学科学院学报

<p><b>OBJECTIVE</b>To observe the effect of the modified artificial esophagus on postoperative stenosis in dogs.</p><p><b>METHODS</b>The models of defected esophagus were established in dogs. The double-layered membrane tube (modifying type) was implanted in the test group (n = 10) and the esophageal stent was further inserted when the stenosis occurred. The single pattern tube (original type) was transplanted to the control group (n = 30). The dilation treatment was performed to relieve the postoperative stenosis; alternatively, the esophageal stent was implanted in the unsuccessful dogs.</p><p><b>RESULTS</b>The average artificial esophagus removal time was 19.10 days in the test group, which was significantly lower than 39.07 days in the control group (t = 15.6, P = 0.000). No obstruction after removal was observed in the experimental group. The incidence of postoperative stenosis had no significant difference between these two groups.</p><p><b>CONCLUSION</b>The double-layered membrane tube can make the tube removal safer by shortening the removal time.</p>