Combination chemotherapy with paclitaxel, cisplatin and fluorouracil for patients with advanced and metastatic gastric or esophagogastric junction adenocarcinoma: a multicenter prospective study

Lymph Node Ratio Is an Independent Prognostic Factor for Patients with Siewert Type II Adenocarcinoma of Esophagogastric Junction: Results from a 10-Year Follow-up Study

PURPOSE

Emerging evidences suggest that lymph node ratio (LNR), the number of metastatic lymph node (LN) to the total number of dissected lymph nodes (NDLN), may predict survival in multiple types of solid tumor. However, the prognostic role of LNR in adenocarcinoma of the esophagogastric junction (AEG) remains uninvestigated. The present study is intended to determine the prognostic value of LNR in the patients with Siewert type II AEG.

METHODS

A total of 342 patients with Siewert type II AEG who underwent R0 resection were enrolled in this study. The optimal cutoff of LNR was stratified into tertiles using X-tile software. The log-rank test was used to evaluate the survival differences, and multivariate Cox regression analyses were performed to determine the independent prognostic variables.

RESULTS

The optimal cutoff of LNR were classified as LNR = 0, LNR between 0.01 and 0.40, and LNR > 0.41. Patients with high LNR had a shorter 5- and 10-year disease-specific survival (DSS) rate (8.5%, 1.4%) compared with those with moderate LNR (20.4%, 4.9%) and low LNR (58.0%, 27.5%) (P < 0.001). Multivariate Cox regression analysis indicated that LNR was an independent factor for DSS after adjusting for confounding variables (P < 0.05). Furthermore, after stratification by NDLN between NDLN < 15 group and NDLN ≥ 15 group, the LNR remained a significant predictor for DSS (P < 0.05).

CONCLUSIONS

LNR is an independent predictor for DSS in patients with Siewert type II AEG regardless of NDLN. Patients with higher LNR have significantly shorter DSS.

Upregulation of miR-34a by diallyl disulfide suppresses invasion and induces apoptosis in SGC-7901 cells through inhibition of the PI3K/Akt signaling pathway

Diallyl disulfide (DADS) exerts anticarcinogenic activity in various types of cancer. However, the mechanism underlying its anticarcinogenic activity remains to be elucidated. The aim of the present study was to explore the mechanism of the anticarcinogenic activity of DADS in gastric cancer (GC). The expression levels of microRNA (miR)-34a in GC and normal tissues were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The expression of miR-34a was also measured using RT-qPCR in SGC-7901 cells following treatment with DADS. In addition, the effect of DADS on the invasion capability of SGC-7901 cells was observed in the presence of miR-34a or anti-miR-34a using a Matrigel invasion assay. Furthermore, in identical conditions, the apoptosis of SGC-7901 cells was observed using flow cytometry. Finally, the present study investigated the effects of DADS and miR-34a on the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway in vitro. The level of miR-34a in GC tissues was reduced compared with that in adjacent normal tissues (P<0.05). Treatment with DADS upregulated miR-34a expression in SGC-7901 cells (P<0.05). In the Matrigel invasion assay, DADS inhibited the invasive capability of SGC-7901 cells (P<0.05 vs. control), which was improved by overexpression of miR-34a (P<0.01 vs. control) but reduced by downregulation of miR-34a (P<0.05 vs. DADS treatment group). Furthermore, DADS induced apoptosis of SGC-7901 cells (P<0.05 vs. control); and DADS and miR-34a synergistically enhanced apoptosis of SGC-7901 cells (P<0.01 vs. control). In addition, DADS and miR-34a inhibited the expression levels of phosphorylated (p)-PI3K and p-Akt (P<0.05 vs. control). By contrast, downregulation of miR-34a alleviated the decrease in p-PI3K and p-Akt expression induced by DADS (P<0.05 vs. DADS treatment group). Cell viability was reduced with increasing concentrations of DADS, however, DADS did not affect cell viability following inhibition of the PI3K/Akt signaling pathway. In conclusion, DADS suppresses invasion and induces apoptosis of SGC-7901 cells by upregulation of miR-34a, via inhibition of the PI3K-Akt signaling pathway.

Resveratrol synergistically augments anti-tumor effect of 5-FU in vitro and in vivo by increasing S-phase arrest and tumor apoptosis

Many studies have shown that natural dietary agents, in combination with chemical agents, can improve the therapeutic response of cancers to chemotherapy and reduce the associated side-effects. In the present study, we investigated the therapeutic potential and mechanisms of anticancer effects for the combination of 5-fluorouracil (5-FU) and resveratrol (Res). In these studies, we employed the cancer cell lines TE-1 and A431 and an animal model of skin cancer. The presented results provide the first evidence that Res can enhance the anti-tumor potency of 5-FU by inducing S-phase arrest. The combination of Res and 5-FU demonstrates synergistic efficacy, causing tumor regression in a two-stage model of mouse skin carcinogenesis induced by DMBA and TPA. There was clear evidence of Res augmenting the growth inhibitory effect of 5-FU on the TE-1 and A431 cancer cells in vitro. In the in vivo studies, the tumor regression rate in the combination group increased significantly after four weeks of treatment (P < 0.01). The combination of 5-FU and Res significantly increased the percentage of apoptotic cells and the level of activated caspase-3, cleaved PARP and p53 proteins as well as increased the Bax/Bcl-2 ratio. In conclusion, the 5-FU/Res combination enabled a more effective inhibition of cell growth and the induction of apoptosis in cancer cells than 5-FU alone. The results of this study suggest that chemotherapy using natural dietary agents with chemical agents represents a superior cancer treatment option.

Risk factors associated with early recurrence of adenocarcinoma of gastroesophageal junction after curative resection

OBJECTIVE

To clarify the important clinicopathological factors affecting the early recurrence of adenocarcinoma of esophagogastric junction (AEG).

METHODS

We retrospectively reviewed the clinical data of 147 AEG patients who underwent R0 resection during the period from December 1995 to December 2007. Risk factors asssociated with the early recurrence were analyzed by χ(2) test and logistic regression test.

RESULTS

The mean time to tumor recurrence was 16.3 months after R0 resection, and the 1-year recurrence rate was 48.3%. Univariate analysis showed that the histological grade (poorly and moderately differentiated), number of positive lymph nodes, and vascular invasion were significantly related with the early recurrence (P<0.05). Logistic multivariate regression analysis showed that only histological grade and vascular invasion were independently related with early tumor recurrence (P<0.05).

CONCLUSIONS

Histological grade and vascular invasion are independent factors for predicting the early tumor recurrence after R0 resection for AEG.

Expression of Rab25 correlates with the invasion and metastasis of gastric cancer

The objective of this study was to determine the expression of the important vesicle trafficking-regulating factor Rab25 in human gastric cancer tissues, to analyze the correlation between Rab25 protein expression with gastric cancer occurrence and development, and to discuss the correlation of Rab25 protein expression with gastric cancer cell metastasis. The overall aim was to provide experimental evidence that can be used to design future biological treatments of human gastric cancer. Human gastric cancer tissue and the adjacent normal gastric tissue were surgically removed, and immunohistochemistry and Western blotting were used to detect Rab25 protein expression. The correlation between Rab25 protein expression with the development and pathological characteristics of gastric cancer was analyzed. Using RNAi, Rab25 expression was reduced in the gastric cancer cell line MGC80-3, and the changes in MGC80-3 cell invasiveness were then monitored. Immunohistochemistry showed that the Rab25 protein expression rates were 78.21% and 23.08% in gastric carcinoma and the adjacent normal gastric tissue, respectively. Immunohistochemistry and Western blot results showed that Rab25 protein expression in gastric cancer was significantly higher than in adjacent normal gastric tissues (P<0.01). Less differentiated gastric cancer cells had higher expression of Rab25 protein (P<0.01). Gastric carcinomas from patients with a late pathological stage (III-IV) had significantly higher Rab25 protein expression than early stage (I-II) patients (P<0.01). Gastric carcinomas from patients with lymph node metastasis had significantly higher Rab25 protein expression than lymph node metastasis-free patients (P<0.01). Gastric carcinomas from patients with distant metastases had significantly higher Rab25 protein expression than the distant metastasis-negative patients (P<0.01). Rab25 protein expression in gastric cancer was not affected by the patients(,) sex, age, or tumor size (P>0.05). MGC80-3 cells transfected with Rab25 siRNA had significantly lower Rab25 protein expression (P<0.01) and a significantly lower number of cells that passed through a Transwell chamber compared with non-transfected controls and the transfected control group (P<0.01). Rab25 protein expression is associated with the development of gastric cancer. siRNA knockdown of Rab25 protein expression in MGC80-3 gastric cancer cells reduced MGC80-3 cell invasiveness and provided experimental evidence for potential future biological treatment strategies of human gastric cancer.

Lymphatic vascular invasion is an independent correlated factor for lymph node metastasis and the prognosis of resectable T2 gastric cancer patients

The objective of this study was to investigate the independent correlated factors for lymph node metastasis (LNM) and prognosis in T2 gastric cancer patients. A total of 135 pathologically confirmed T2 gastric cancer patients who received a gastrectomy at the Beijing University Cancer Hospital from Dec 1999 to Dec 2006 were studied retrospectively. The potential correlated factors for LNM and patients' prognosis were analyzed, including gender, age, tumor location and size, depth of invasion, lymphatic vascular invasion (LVI), differentiation grade, histological type, Borrmann type, LNM, distant metastasis, TNM stage, and whether the patient was treated with a radical gastrectomy. LNM occurred in 69 patients, which represents a rate of LNM of 51.1 %. Multivariate logistic regression analysis showed that LVI and TNM stage were independent risk factors for LNM (p values were 0.002 and 0.029, respectively). The median follow-up time was 60.3 months. Multivariable survival analysis revealed that age (<60 vs. ≥ 60), TNM stage and LVI were independent prognostic factors for gastric cancer patients (p values were <0.001, 0.047, and 0.001, respectively). In conclusion, LVI was an independent factor for LNM and the prognosis of resectable T2 gastric cancer patients.