Search

Plant cells frequently undergo endoreduplication, a modified cell cycle in which genome is repeatedly replicated without cytokinesis. As the key step to achieve final size and function for cells, endoreduplication is prevalent during plant development. However, mechanisms to control the balance between endoreduplication and mitotic cell division are still poorly understood. Here, we show that the Arabidopsis TCP (CINCINNATA-like TEOSINTE BRANCHED1-CYCLOIDEA-PCF)-family transcription factor gene AtTCP15 is expressed in trichomes, as well as in rapidly dividing and vascular tissues. Expression of AtTCP15SRDX, AtTCP15 fused with a SRDX repressor domain, induces extra endoreduplication in trichomes and cotyledon cells in transgenic Arabidopsis. On the contrary, overexpression of AtTCP15 suppresses endoreduplication in trichomes and other examined cells. Misregulation of AtTCP15 affects the expression of several important genes involved in cell-cycle regulation. AtTCP15 protein binds directly to the promoter regions of CYCA2;3 and RETINOBLASTOMA-RELATED (RBR) genes, which play key roles in endoreduplication. Taken together, AtTCP15 plays an important role in regulating endoreduplication during Arabidopsis development.

Objective: To observe the clinicopathological characteristics of gastric cancer with pathological complete response(pCR) following neoadjuvant chemotherapy., Methods: Data of gastric cancer patients who received neoadjuvant chemotherapy from 2002 to 2008 in the Beijing Cancer Hospital were reviewed. Five cases were found to have pCR. The slides were reviewed by two experienced pathologists independently. Histological structure, morphology of tumor cells, morphology and quantity of stromal cells were evaluated., Results: Structure of the gastric wall was distinguishable in all the 5 cases, while distortion and rupture of muscular layer were found in 2 cases. Exudative inflammatory reaction was present in the whole gastric wall including the serosa layer. Three patients had ulcerative lesions with epithelial layer shedding, and atypical hyperplasia was found around the border of the ulcer, and vascular endothelial cells were swollen. Residual distorted necrotic tumor cells resided in 1 case only and no residual tumor cells was present in the other 4 patients. Significant hyperplasia of fibroblasts was present in 4 cases, large amount of lymphocytes infiltration in 3 cases including concurrent plasma cell infiltration in 1 case, multinucleated giant cell reaction in the muscular layer of 1 case, and foam cells aggregation in 1 case with mucinous adenocarcinoma. In addition, there were 2 cases with pCR had lymph node metastasis., Conclusions: For cases with pCR following neoadjuvant chemotherapy, heterogeneity of stromal cells reaction is found in previous tumor site. Furthermore, the response of primary tumor does not necessarily parallel to that of lymph nodes.

Objective: To study the status of splenic hilar lymph nodes(No.4sa, No.10 or No.11d lymph nodes) metastasis and to investigate the proper dissection technique in patients with advanced gastric cancer., Methods: A retrospective study was performed to investigate 590 patients who underwent D2 curative proximal or total gastrectomy for gastric carcinoma from January 2006 to December 2009. Clinicopathological factors such as sex, age, location of the primary tumor, tumor sizes, gross type, depth of invasion, microscopic classification, neoadjuvant chemotherapy and the metastasis of adjacent lymph node were analyzed with univariate and multivariate analysis. Influence of combined splenectomy or pancreatectomy on lymph node dissection was also investigated., Results: The overall ratio of metastatic lymph node(positive lymph nodes/lymph nodes harvested) in the splenic hilum was 17.5%(99/565). The positive rates of No.4sa, No.10, No.11d lymph nodes were 17.8% (41/230), 13.9%(29/209), and 22.8%(29/127), respectively. A total of 7.1%(42/590) of the patients had lymph node metastasis in the splenic hilum. Multivariable logistic regression analysis showed that age, tumor size, depth of tumor invasion, positive metastasis of No.4sb lymph node were independent risk factors for lymph node metastasis in the splenic hilum region. When comparing patients undergoing combined splenectomy or pancreatectomy(n=23) and those who did not undergo combined organ resection (n=553), the ratios of metastatic lymph node in the splenic hilum were 14.8%(4/27) and 17.2%(91/527), respectively, and the difference was not statistically significant(P>0.05). The postoperative complication rates were 26.1%(6/23) and 5.4%(30/553), respectively, and the difference was statistically significant(P<0.05). The operative mortality rates were 4.3% and 0.9%, respectively, and the difference was not statistically significant(P>0.05)., Conclusions: Metastasis to lymph nodes in the splenic hilum region in patients with gastric cancer possesses a certain pattern, and it is associated with tumor location, size, depth of invasion, and metastasis in No.4sb. Combined resection of the spleen or pancreas does not result in increased number of harvested lymph nodes or positive lymph nodes, yet is associated with higher complication rate. Therefore, combined organ resection should be meticulous.

Objective: To compare the expression of human epidermal growth factor receptor 2 (HER2) under different scoring systems in gastroesophageal cancer and its relationship with clinicopathological features., Methods: Clinicopathological data were retrospectively reviewed of 127 patients with gastroesophageal cancer between January and December 2009 in the Department of Surgery at the Cancer Hospital of Peking University. Tumor specimens were collected. The expression of HER2 protein was detected by immunohistochemistry., Results: HER2 positive rate(++/+++) in gastroesophageal cancer was 15.0%(19/127) with both new and traditional immunohistochemical scoring systems, while HER2 strong positive rate(+++) was 10.2%(13/127) and 6.3%(8/127), respectively(P=0.26). Univariate analysis showed that the expression rate of HER2 protein was associated with differentiation and Lauren classification of the tumor. Multivariable analysis showed that TNM staging and tumor differentiation were independently associated with the expression of HER2 protein(both P<0.05)., Conclusions: There is no change in HER2 positive rate in gastroesophageal cancer between the new and traditional immunohistochemical scoring systems. Expression of HER2 is associated with clinicopathological features in the gastroesophageal cancer.

This pilot study was undertaken to assess the effect of weekly docetaxel, cisplatin and fluorouracil (DCF) as a preoperative treatment for gastric cancer with multiple synchronous hepatic metastases. Gastric cancer patients with synchronous multiple liver metastasis were first given preoperative chemotherapy consisting of two courses (each course consisted of 6-week administration and 2-week withdrawal) of weekly DCF regimen. Following the operation, postoperative chemotherapy and hepatic arterial infusion (HAI) treatment were performed as required. Eight patients completed two courses of preoperative chemotherapy with weekly DCF regimen. No toxicity of grade 3 or more was observed during the course of chemotherapy. The response rate was 100% according to the RECIST criteria. Seven of the patients have survived for over 1 year, and six of them are still alive after more than 1 year. Because of the unexpected high response to weekly DCF, we consider that it should be verified through phase II and III trials as an important part of the comprehensive treatment for gastric cancer with liver metastasis.

Objective: To clarify the important clinicopathological and therapeutical factors affecting the prognosis of patients with gastroesophageal junction carcinoma., Methods: Data of 514 cases with gastroesophageal junction carcinoma who underwent surgical treatment from September 1995 to January 2007 was retrospectively analyzed. Relevant prognostic factors were studied with univariate and multivariate analysis., Results: For all 514 cases (424 men and 90 women), the median age was 63 years. The 1-, 3- and 5-year survival rates of this group were 74.8%, 42.1% and 29.1%, respectively. Gross type, TNM classification, histological type, vascular invasion and extent of surgical resection affected patients' survival remarkably. There was no significant difference in survival between operative approaches (via laparotomy or left thoracotomy) (P > 0.05). Long-term survival was similar between proximal subtotal gastrectomy and total gastrectomy in advanced cases (P > 0.05). For stage II and III tumors, patients with neoadjuvant chemotherapy had better prognosis than those without (P < 0.05). Cox multivariate regression analysis revealed TNM classification and vascular invasion were independent prognostic factors., Conclusions: TNM classification and vascular invasion are independent prognostic factors for gastroesophageal junction carcinoma. Neoadjuvant chemotherapy may improve prognosis of the patients with stage II and III tumors. Radical resection should be achieved with rational surgical procedures tailored by tumor position, size, staging and so on.

Objective: To explore the pattern of lymph node metastasis and its influence on the prognosis of early gastric cancer(EGC)., Methods: The pattern of lymph node metastasis and the 3-,5-year survival rates in 157 EGC patients undergone surgery from October 1995 to October 2005 were analyzed retrospectively. The SPSS 11.5 statistics software was used to perform univariate and multivariate analysis., Results: Twenty-two cases had lymph node metastasis among 157 EGC patients(14%). Two mucous cancers(2.4%) and 20 submucosal tumors(27.0%) had lymph node metastases (P<0.01). Lymph node metastasis was not seen in minute gastric cancer(diameter < or =0.5 cm). Lymph node metastasis rates were 6.4% in the cancers with diameter 1.1-2.0 cm and 21.5% in the cancers with the diameter >2.0 cm(P<0.01). Besides, lymph node metastasis rate of well-differentiated EGC was 0, of moderate differentiated EGC 11.1%, and poor-differentiated EGC 0.9%(P<0.01). Of 9 cases with vascular cancer embolus, 4 had lymph node metastases. Logistic regression analysis showed that tumor size, vascular cancer embolus, histopathological type and depth of invasion were independent factors of lymph node metastasis in EGC. The 3- and 5-year survival rates of EGC patients with lymph node metastasis were 81.6 % and 79.5% respectively, which were much lower than those without lymph node metastasis(95.7% and 93.2%, P<0.01)., Conclusions: Lymph node metastasis in EGC is mainly correlated with depth of infiltration, tumor size, vascular cancer embolus and differentiation. For EGC treatment, choice should be made reasonably based on the risk of lymph node metastasis.

Objective: To explore the CT criteria for evaluating lymph node (LN) metastasis and preoperative N-staging of gastric cancer through the comparison of CT signs and surgical pathology., Methods: Eighty-nine patients with gastric cancer underwent CT examinations before radical resections. A soft-reading method on PACS workstation was employed to evaluate the detection of LNs. The size and number of LNs were registered, and the accumulated size of LNs was calculated in every case. The pathological N-staging (pN(0-3)) was considered on the basis of pathological examination of excised specimens according to UICC TNM-staging system (6th edition, 2002). The relationships between LN metastases and CT findings were analyzed by SPSS using t test and one-way ANOVA analysis., Results: The distribution of maximal size, CT detection number and accumulated size were significantly different among different pN stages (P<0.01). All these 3 indicators were significantly different between LN metastasis group and non-metastasis group (P<0.01). There was no significant difference of maximal size among different pN stages in positive metastasis LNs (P>0.05), while significant difference could be found in CT detection number between pN1 and pN3 (P<0.01), pN2 and pN3 (P<0.01), and in accumulated size between pN1 and pN3 (P<0.01), pN1 and pN2 (P<0.01)., Conclusions: The involvement of LNs in gastric cancer and pN staging are associated with size, number, and accumulated size of CT detection. CT detection number is more valuable in the evaluation of N staging than LNs size. CT detection number combined with accumulated size of LNs can provide meaningful information for preoperative N-staging.

Objective: To examine the utility of the Ligasure vessel-sealing system in D(2) lymphadenectomy of gastric cancer, and compare with conventional hand tie method., Methods: One hundred and twenty-four consecutive patients undergone D(2) lymphadenectomy of gastric cancer from Jan. to Oct. 2005 were enrolled in this study. Operations of 62 patients were performed with Ligasure, whereas the other 62 patients with hand tie method. Operative duration, volume of intraoperative hemorrhage and postoperative course were analyzed., Results: There was significant difference in operative duration (187.3 min vs 210.5 min, P< 0.05) and no significant differences in volume of intraoperative hemorrhage, postoperative course, or duration of postoperative drainage between Ligasure group and conventional method group. No significant difference was observed in the frequency of postoperative complications between the two groups., Conclusion: D(2) lymphadenectomy of gastric cancer using Ligasure instead of conventional hand tie method appears to be technically feasible and easy.

Pancreatic cancer remains a major troublesome clinical problem, with conventional cancer treatments having little impact on disease course. The extent of disease is often classified as localized, locally advanced, and metastatic. Radical operation is the most effective method, but only 15%-20% of patients have resectable disease, and around 20% of them survive to 5 years. For locally advanced, unresectable, and metastatic diseases, palliative treatment is more appropriate, but the median survival in these patients is less than 6 months and the 5-year survival rates are even lower than 4%. Neoadjuvant therapy has been gradually accepted in breast cancer and gastroenterological cancer, and its value in pancreatic cancer has attracted increasing interests. This paper reviews recent advances of neoadjuvant therapy in pancreatic cancer.