Mechanisms of human telomerase reverse transcriptase RNAi which increases hepatocellular carcinoma cell apoptosis induced by TRAIL / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To investigate the mechanisms for human telomerase reverse transcriptase (hTERT) RNA interference (RNAi) in increasing hepatocellular carcinoma cell apoptosis induced by TNF-related apoptosis-inducing ligand (TRAIL).</p><p><b>METHODS</b>Cell apoptosis was identified by flow cytometry analysis after annexin V/PI double staining. Expression of apoptosis-related proteins, procaspase-8, -9, -3, Bax, Bcl-2 and hTERT, were identified by Western blotting analysis; telomerase activity and telomere length were detected by telomeric repeat amplification protocol (TRAP) and telomere amount and length assay (TALA) methods.</p><p><b>RESULTS</b>Hepatocellular carcinoma cell apoptosis induced by TRAIL were all significantly increased by hTERT RNAi (P less than 0.05). For example, apoptosis rates were enhanced from 5.53% (untransformed) to 10.35% (transformed) in HepG 2 cells and from 14.73% to 77.24% in SMMC 7721 cells after being treated by 100 ng/ml TRAIL for 24 h. Moreover, activation of procaspase-8, -9 and -3 in transformed cells after being treated by TRAIL were all significantly raised (P less than 0.05) in a dose-dependent manner. The expression of procaspase-8, -9 and Bcl-2 were effectively augmented (P less than 0.05), but expressions of Bax and hTERT were strikingly decreased (P less than 0.05). Meanwhile, telomerase activity was apparently suppressed and telomere length was markedly shortened (P less than 0.05). There were no remarkable differences in these effects between control cells and the untransformed cells (P more than 0.05).</p><p><b>CONCLUSION</b>Enhanced cell apoptosis induced by TRAIL through hTERT RNAi may be related to up-regulation of procaspase-8 and -9 expressions. However the down-regulation of hTERT expression, reduced telomerase activity and shortened telomere length may not be related to expressions of Bcl-2 and Bax.</p>

Effects of hTERT RNAi on apoptosis of hepatocellular carcinoma cells induced by TRAIL / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the effects of human telomerase reverse transcriptase (hTERT) RNA interference (RNAi) on biological characteristics of hepatocellular carcinoma cell lines HepG2 and SMMC-7721 and on apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL).</p><p><b>METHODS</b>Small hairpin hTERT (shTERT) sequence was identified by PCR method; hTERT expressions, morphological features, cell proliferation and replicative senescence were respectively determined using RT-PCR, hematoxylin-eosin (HE) staining, growth curve and beta-galactosidase (b-Gal) staining; cell cycle and apoptosis were identified using flow cytometry after propidium iodide (PI) staining and annexin V/PI double staining.</p><p><b>RESULTS</b>shRNA were found in 6/8 HepG2 and 6/6 SMMC-7721 cell clones transformed by the recombined plasmid pSilencer 3.1-H1 neo-shTERT. The interference rates of hTERT on HepG2 and SMMC-7721 were 100% and 43.3% respectively. Cells in G2-M phases increased from 7.1% to 10.6% and from 6.9% to 7.9% respectively; and the percentage of replicative senenscence cells increased from 0 to 20.4% and from 3.6% to 10.0% respectively. The nucleus/cytoplasm ratios of the cells were obviously decreased after hTERT RNAi treatment. Moreover, apoptosis of hepatocellular carcinoma cells and apoptosis induced by TRAIL were strikingly increased by hTERT RNAi (P < 0.05). For example, apoptosis rates were increased from 3.5% to 5.2% in HepG2 cells and from 4.8% to 7.9% in SMMC-7721 cells after hTERT RNAi treatment. Apoptosis rates were increased from 5.3% to 10.4% in HepG 2 cells and from 13.9% to 77.2% in SMMC-7721 cells after being treated by 100 ng/ml TRAIL for 24 h. However, there were no remarkable changes between control cells and untransformed cells.</p><p><b>CONCLUSION</b>hTERT RNAi not only has a significant effect on biological characteristics of hepatocellular carcinoma cells, but also obviously can increase cell apoptosis induced by TRAIL.</p>

Postoperative respiratory failure in patients with cancer of esophagus and gastric cardia / 中华肿瘤杂志

<p><b>OBJECTIVE</b>We retrospectively analyzed the cause and death risk of 114 postoperative respiratory failure patients found in 3519 patients with esophageal cancer and 1495 patients with carcinoma of gastric cardia surgically treated between January 1992 and May 2003.</p><p><b>METHODS</b>To analyze the reasons causing postoperative respiratory failure in surgically treated esophageal or gastric cardia cancer patients, and the correlation between the death risk of postoperative respiratory failure and preoperative pulmonary function tests, postoperative complications, operation modes, history of preoperative accompanying diseases and so on using Binary Logistic Regression analysis and Chi-square tests (chi(2)) in SSPS statistics software.</p><p><b>RESULTS</b>In this series, postoperative respiratory failure developed in 97 of 3519 (2.76%) esophageal cancer patients and 17 of 1495 (1.14%) gastric cardia cancer patients, which were mainly caused by severe respiratory tract infection (37.7%, 43/114) and operative complications (35.1%, 40/114) such as: anastomotic leakage or perforation of thoracic stomach, extensive bleeding during operation, chylothorax, etc, totally accounting for 72.8% (83/114). In contrast with lung cancer patients, most of the postoperative respiratory failure (69.3%) occurred in the patients who had perioperative complications but almost always normal preoperative pulmonary function tests. Other reasons to cause postoperative respiratory failure were: extubation in unconscious patients at the end of general anesthesia; over-infusion during operation; pulmonary artery embolism; severe arrhythmia and so on. All patients except 2 were treated in ICU by mechanic ventilation through intubation and/or tracheotomy. Eighty patients (70.2%) were intubated and/or had tracheotomy within 3 days postoperatively. Seventy patients (61.4%) were rescued successfully, whereas 44 cases (38.6%) died of postoperative respiratory failure and/or other postoperative complications. Univariate analysis and multivariate analysis by binary logistic regression indicated that: severe perioperative complications, more postoperative complications, poor preoperative pulmonary function, radical preoperative radiotherapy, intubation and/or tracheotomy after the second postoperative day and long period of mechanic ventilation were the major risk factors leading to death once the postoperative respiratory failure developed. The former 3 factors were independent risk factors leading to death with OR of 2.50, 2.37, 1.68, respectively. Age, sex, operation modes, history of preoperative accompanying disease, prophylactic antibiotics were not demonstrated as statistically significant risk factors correlated with death.</p><p><b>CONCLUSION</b>Severe perioperative complications and respiratory tract infection are the two major causes of postoperative respiratory failure in patients with cancer of esophagus and gastric cardia. Patients with severe perioperative complications or poor preoperative pulmonary function or association with more than two kinds of postoperative complications have much higher death risk than other patients when they develop postoperative respiratory failure. Careful manipulation during operation and effective perioperative management are the most important measures to avoid postoperative respiratory failure and high mortality.</p>

Diagnosis and surgical treatment for stage I non-small-cell lung cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the results of surgery and the diagnosis of stage I non-small-cell lung cancer (NSCLC).</p><p><b>METHODS</b>The survival of 274 stage I NSCLC patients who underwent surgery from 1991 to 1998 were statistically analyzed by the Kaplan-Meier method. Comparison of the differences in survival rates among groups were made according to the Logrank test. The follow-up time was at least 5 years with a follow-up rate of 97.8%.</p><p><b>RESULTS</b>The overall 1-, 3-, 5-year survival rates for patients with pathologic stage I lesion were 92.9%, 79.6% and 66.1%. The 5-year survival rates for patients with squamous-cell carcinoma, adenocarcinoma, adenosquamous and alveolar-cell carcinoma were 73.3%, 55.3%, 52.2%, 71.7%, respectively. The 1-, 3-, 5-year survival rates for T1N0 were 95.0%, 83.2%, 74.3% whereas those of T2N0 lung lesions were 90.8%, 75.9%, 59.9% (P < 0.05). The 1-, 3-, 5-year survival rates of regular lobectomy were 94.1%, 79.3%, 67.5% and of conservative resection (segmentectomy and wedge resection) were 76.5%, 50.0%, 38.3% (P < 0.05). There was no perioperative mortality. The postoperative complications were: intrathoracic hemorrhage (2 patients, successfully treated by second thoracotomy) and chylothorax (1 patient, healed after conservative treatment).</p><p><b>CONCLUSION</b>The 5-year survival rate of pathologic stage I non-small-cell lung cancer is 66.1%. The outcome of patients with squamous-cell carcinoma (73.3%) is similar to that of alveolar-cell carcinoma (71.7%) which, however, is better than that of adenocarcinoma (55.3%) or adenosquamouscarcinoma (52.5%). The overwhelming superiority in result of IA (T1N0) lesion (74.3%) over the IB (T2N0) disease (59.9%) is quite impressive. Regular lobectomy plus radical mediastinal lymph node dissection is the appropriate management for stage I non-small-cell lung cancer.</p>

Myasthenia gravis occurring after resection of thymoma / 中华外科杂志

<p><b>OBJECTIVE</b>The aim of this study was to analyses the clinicopathologic features of the patient with myasthenia gravis (MG) occurring after resection of thymoma.</p><p><b>METHODS</b>Data of 15 patients were collected. The follow-up range from 8 to 178 (average 76.7) months. A retrospective analysis was performed through comparison with data of all 112 cases without MG, which had not occurred MG during our average 5.5 years follow-up, operated for thymoma in same period. The statistics analysis adopted chi(2) and t test.</p><p><b>RESULTS</b>(1) According to Masaoka's classification of thymoma, stage I in 7 cases, stage II in 4, stage III in 4. Histologic Bernatz's classification: lymphocyte predominant type in 4, epithelial type in 3, mixed type in 7, unknown in 1. According to Osserman's classification of MG, grade I in 7, IIa in 4, IIb in 3, III in 1. The MG onset times was the postoperative narcotic waking duration-137 (average 33.9) months, and the average remission time was 30.9 (0.5 - 120) months. (2) 4 cases who occur MG as soon as pull up narcotic tube, all adopted nondepolarizing muscular relaxants. (3) MG was discovered in 3 cases (3/67) during postoperative radiotherapy until a average dosage of 36 Gy was received in average 24 days. (4) The tendency of occurring MG following resection was found in female patients with longer duration of disease, mixed type, larger and later stage thymoma as compared with the thymoma group.</p><p><b>CONCLUSIONS</b>The factors including the operation, relatively using overdose relaxation control, choosing unfavorable muscle relaxant and postoperative radiotherapy could induce postoperative MG. An intensive care should be put on the cases with the tendency of occurring postoperative MG.</p>

Clinicopathological features and prognosis of thymic carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the clinicopathologic features of thymic carcinoma and assess its prognostic factors.</p><p><b>METHODS</b>A retrospective analysis was performed in 54 patients with thymic carcinoma who underwent surgical resection. Eighteen patients were treated by total resection of the tumor, 17 partial resection and 10 exploratory thoracotomy. The clinical stage was determined according to Masaoka's classification. The survival time and prognostic factors were evaluated by the log-rank and Cox multivariate analysis model.</p><p><b>RESULTS</b>The overall 5-year survival rate was 44.4%. Being located in anterior mediastinum and noncalcification in the tumor pathognomonically played an important role in the differential diagnosis. According to the multivariate analysis, tumor maximum diameter (OR = 1.84), histological subtype (OR = 1.70), completeness of resection (OR = 1.37), tumor invasion of peritumoral organs (OR = 1.32) and postoperative recurrence (OR = 1.26) were significant prognostic factors. Compared with other subtypes, carcinoid tumor had the characteristics of earlier lesion, better resection rate and better prognosis.</p><p><b>CONCLUSION</b>The most important prognostic variables for thymic carcinoma are tumor maximum diameter, histological subtype, completeness of resection, tumoral invasion and postoperative recurrence. Complete resection followed by chemoradiotherapy should be considered as favorable on the basis of a definitive pathologic diagnosis.</p>

Clinical features of postoperative chylothorax for lung cancer and esophageal cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To define the clinical features of postoperative chylothorax for lung cancer (PCLC), and to compare them with those for esophageal cancer (PCEC).</p><p><b>METHOD</b>We retrospectively analysed clinical characteristics of 12 patients with chylothorax among 4 084 patients receiving resection of lung cancer, as well as 52 in 4 479 patients having resection of esophageal cancer since 1985 at our hospital.</p><p><b>RESULTS</b>The incidence of PCLC was 0.29% and that of PCEC was 1.16%. The percentage of diagnosis confirmed within 4 postoperative days was 33.3% for PCLC, and 76.9% for PCEC. The rate of typical chylous pleural effusion was 83.3% for PCLC, and 5.8% for PCEC. Symptoms and signs of PCLC were much milder than those of PCEC. The re-operation rate was 16.7% for PCLC, and 96.2% for PCEC. All patients were discharged uneventfully.</p><p><b>CONCLUSION</b>The incidence, causes, clinical manifestations, diagnosis, and treatment of PCLC is different from those of PCEC.</p>

Antisense DNMT1 gene fragment in the sensitivity change of SMMC-7721 cells to tumor necrosis factor related apoptosis inducing ligand and its mechanism / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To observe the sensitivity change of SMMC-7721 cells transfected with antisense DNMT1 gene fragment to tumor necrosis factor related apoptosis inducing ligand (TRAIL) and its mechanism.</p><p><b>METHODS</b>Cell survival rate was measured by trypan blue, apoptosis rate by TUNEL method and the expression of bcl-2, bax and bad by flow cytometry.</p><p><b>RESULTS</b>Cell survival rate of SMMC-7721 cells transfected with antisense DNMT1 gene fragment was markedly lower than that transfected with sense DNMT1 gene fragment or empty vector (P < 0.05 and 0.01), but the apoptosis rate was on the contrary (P < 0.05 or 0.01). The expression of bax and bad (especially the former), but not bcl-2 of SMMC-7721 cells transfected with antisense DNMT1 gene fragment was markedly higher than those of SMMC-7721 cells transfected with sense DNMT1 gene fragment or empty vector.</p><p><b>CONCLUSION</b>The sensitivity of SMMC-7721 cells to TRAIL can be enhanced by the transfection of antisense DNMT1 gene fragment, which may be related to the increase of bax and bad expression.</p>

Cooperative anti-tumor effect of aspirin and TNF-related apoptosis-inducing ligand / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To observe the anti-tumor effect of combination TNF-related apoptosis-inducing ligand (TRAIL) with aspirin on liver cancer cell line, SMMC-7721.</p><p><b>METHODS</b>The survival fraction of SMMC-7721 cells was measured by MTT assay, apoptosis rate and cell cycle was determined by flow cytometry, and the expression of apoptosis-related gene was identified by western blot.</p><p><b>RESULTS</b>The survival fraction of SMMC-7721 cells treated with 300 ng/ml TRAIL, 3 mmol/L or 10 mmol/L aspirin alone was 82.76%, 81.34% and 71.29% respectively, and the survival fractions of SMMC-7721 cells treated with TRAIL and 3 mmol/L or 10 mmol/L aspirin were 43.54% and 37.8% respectively. The apoptosis rates of SMMC-7721 cells induced by TRAIL and 3 mmol/L or 10 mmol/L aspirin were higher than that induced by TRAIL or aspirin alone (34.76% and 38.56% vs 21.25%, 1.89% and 6.08%), and G0/G1 arrest was observed under TRAIL and aspirin. The expression of Bcl-2 in SMMC-7721 cells treated by 3 mmol/L or 10 mmol/L aspirin decreased markedly, but no effect on Bax.</p><p><b>CONCLUSION</b>The cooperative anti-tumor effect of aspirin and TRAIL may be related to the inhibition of the expression of Bcl-2 by aspirin</p>

Clinical analysis of surgical treatment of primary tracheal tumors / 中华外科杂志

<p><b>OBJECTIVE</b>To summarize the clinical experiences in treating primary tracheal tumors by surgery.</p><p><b>METHODS</b>The clinical data concerning 70 surgically treated patients between 1968 and 2001 were retrospectively analyzed.</p><p><b>RESULTS</b>There were 39 sleeve tracheal resections, 13 carinal resections, 10 lateral tracheal wall resections, 5 local enucleations, and 1 pneumonectomy. The tumors in 2 patients were unresectable. The morbidity rate was 31% (22/70) and operative 30-day mortality for resection with primary reconstruction was 8% (4/52). The tumors were benign in 14 and malignant in 56 cases. The most common malignant tumors were adenoidcystic carcinoma (45%) and squamous cell carcinoma (23%). The cases of benign tracheal tumors were followed up for an average of 5.7 years. After resection for malignant tumors, the overall 5- and 10-year survival rates were 64% (21/33) and 54% (14/26), respectively.</p><p><b>CONCLUSIONS</b>Surgical resection is the most effective treatment of tracheal tumors. Tracheal resection and reconstruction is the treatment of choice for primary tracheal tumors. Benign tumors should be resected conservatively with preservation of tracheal parenchyma. The reduction of operative complications are key points of good surgical results.</p>