Guanine nucleotide-binding protein subunit beta-4 promotes gastric cancer progression via activating Erk1/2

Gastric cancer (GC) is one of the most common and lethal malignancies worldwide, and its poor prognosis is mainly due to the rapid tumor progression including tumor invasion, distant metastasis, etc. Understanding the molecular mechanisms regulating GC progression lays the basis for the development of targeted therapeutic agents. Increasing evidence suggests that guanine nucleotide-binding protein subunit beta-4 (GNB4), a key subunit of heterotrimeric G protein, plays a crucial role in the initiation and progression of multiple malignancies. However, whether and how GNB4 promotes GC progression are still unknown. In this study, we found that GNB4 was highly expressed in GC tissues compared to that in non-tumor tissues and was significantly associated with tumor invasion depth, pathological stage and poor survival rate of GC patients. Both gain-of-function and loss-of-function studies revealed that GNB4 significantly enhanced GC cell growth and motility both in vitro and in vivo. Further studies revealed that GNB4 overexpression induced G1-S transition and promoted the process of epithelial-mesenchymal transformation. These tumor promoting effects were mediated by GNB4 which activates the Erk1/2 pathway through upregulating Erk1/2 phosphorylation, as U0126, an Erk1/2 phosphorylation inhibitor, could significantly inhibit GNB4-mediated cell proliferation, migration and invasion. In summary, GNB4 contributes to the proliferation and metastasis of GC cells by activating the Erk1/2 signaling pathway, and it may serve as a potential therapeutic target of GC.

Systemic inflammation score is a prognostic marker after curative resection in gastric cancer

Background

The systemic inflammation score (SIS), as calculated from preoperative serum albumin level and lymphocyte‐to‐monocyte ratio, has been demonstrated to be a prognostic marker in cancer. The present study intended to investigate the prognostic role of SIS in gastric cancer patients after curative gastrectomy in comparison with other prognostic markers.

Methods

Preoperative SIS was retrospectively calculated in patients who underwent curative gastrectomy between 2007 and 2011 in Fudan University Shanghai Cancer Center. The prognostic accuracy of each score was compared utilizing time‐dependent receiver operating characteristics analysis.

Results

The higher SIS score was associated with older age, larger tumour size, a more advanced tumour‐nodes‐metastasis stage and lymph node status, deeper tumour invasion, the presence of lymphovascular invasion and a poorer overall survival and disease‐free survival. In time‐dependent receiver operating characteristics analysis, the SIS had a higher area under the curve for the prediction of 5‐year overall survival than the neutrophil lymphocyte ratio. The SIS maintained the predictive accuracy superiority throughout the observation period.

Conclusion

The SIS is a useful prognostic marker in gastric cancer patients after curative gastrectomy.

Chinese consensus on management of tyrosine kinase inhibitor-associated side effects in gastrointestinal stromal tumors

Tyrosine kinase inhibitors (TKIs) have improved the overall survival of patients with gastrointestinal stromal tumors (GISTs), but their side effects can impact dose intensity and, consequently, the clinical benefit. To date, no guideline or consensus has been published on the TKI-associated adverse reactions. Therefore, the Chinese Society of Surgeons for Gastrointestinal Stromal Tumor of the Chinese Medical Doctor Association organized an expert panel discussion involving representatives from gastrointestinal surgery, medical oncology, cardiology, dermatology, nephrology, endocrinology, and ophthalmology to consider the systemic clinical symptoms, molecular and cellular mechanisms, and treatment recommendations of GISTs. Here, we present the resultant evidence- and experience-based consensus to guide the management of TKI-associated side events in clinical practice.

Comparative effectiveness of adjuvant treatments for resected gastric cancer: a network meta-analysis

BACKGROUND

Different adjuvant treatments are available for patients with gastric cancer, but conventional meta-analyses performing direct comparisons between two alternative treatments did not have enough power to compare all the adjuvant treatments. Thus, we did a network meta-analysis summarizing the direct and indirect comparisons to identify the optimum treatment.

METHODS

We systematically searched for RCTs of adjuvant treatments for gastric cancer comparing two or more of the following treatments: surgery alone, radiotherapy with fluoropyrimidine, S-1-based regimens, and XELOX. The treatments offering available indirect evidence to investigate the comparative effectiveness of adjuvant treatments mentioned above were also included. Then we performed a Bayesian network meta-analysis to summarize the direct and indirect comparisons. We estimated hazard ratios with 95% credible intervals (CrI) for OS and DFS.

RESULTS

11 eligible RCTs (5620 patients) were included in the network meta-analysis. Radiotherapy with fluorouracil (5-FU/RT), S-1-based regimens, and XELOX significantly improved OS as compared with surgery alone [(HR = 0.75 with 95% CrI: 0.63-0.89), (HR = 0.63 with 95% CrI: 0.52-0.76), and (HR = 0.66 with 95% CrI: 0.51-0.85), respectively]. No treatment was clearly superior to others; however, S-1-based regimes and XELOX showed a statistically non-significant trend to better survival as compared with 5-FU/RT.

CONCLUSIONS

S-1-based chemotherapy and XELOX are likely to be the most effective adjuvant treatments for patients with resected gastric cancer. 5-FU alone provided little survival benefits as compared with surgery alone. Further clinical trials may be required to investigate S-1-based and XELOX-based adjuvant treatment strategies.

[Current status of surgical treatment of gastric gastrointestinal tumors: a national multi-center retrospective study]

OBJECTIVE

To retrospectively analyze the clinicopathology of patients with gastric gastrointestinal stromal tumor(gGIST) who underwent radical excision within 18 years in 10 domestic medical centers in order to understand the status of domestic surgical treatment of gGIST.

METHODS

Clinicopathological data of gGIST patients undergoing radical excision in 10 medical centers from January 1998 to January 2016 were collected, and their operational conditions, postoperative adjuvant therapy, gene detection and survival were analyzed retrospectively.

RESULTS

A total of 1 846 cases were recruited in this study, including 246 cases from Guangdong General Hospital, 331 cases from Sun Yat-sen University Cancer Center, 374 cases from Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, 342 cases from Nanfang Hospital of Southern Medical University, 265 cases from Fujian Medical University Union Hospital, 148 cases from Fudan University Shanghai Cancer Center, 49 cases from West China Hospital of Sichuan University, 43 cases from Peking University Cancer Hospital and Institute, 28 cases from the 81st Hospital of Pepole's Liberation Army(PLA), 20 cases from Cancer Hospital of China Medical University, Liaoning Cancer Hospital and Institute. There were 918 male (49.7%) and 928 female patients (50.3%) with median onset age of 59(18 to 95) years old. Fundus(735 cases, 39.8%) and body (781 cases, 42.3%) of stomach were the common sites of lesions. The average size of tumor was (5.3±4.6) cm. There were 1 421 cases with mitotic count ≤5(77.0%). According to the operation procedure, 924 cases (50.1%) underwent laparoscopic surgery, 759 cases (41.1%) laparotomy, 120 cases (6.5%) endoscopic surgery, and 20 cases (1.1%) laparoscopic combined with endoscopic surgery, 6 cases (0.3%) laparoscopic excision surgery through gastric wall and cavity, and 17 cases (0.9%) laparoscopy and then were transferred to laparotomy. Wedge excision were performed in 1 308 cases (70.9%), proximal gastric excision in 226 cases(12.2%), distal gastric excision in 92 cases (5.0%), total gastrectomy in 94 cases (5.1%), and local gastrectomy in 126 cases(6.8%). Multi-visceral excision was performed in 138 cases, and the splenectomy was performed in 83 cases(60.1%)with the highest ratio. According to modified NIH classification, 399 cases(21.6%) were extreme low risk, 580 cases(31.4%) were low risk, 424 cases(23.0%) were moderate risk, 443 cases (24.0%) were high risk. A total of 461 cases received postoperative imatinib adjuvant therapy, accounting for 53.2%(461/867) of patients with moderate and high risk. Among 1 846 cases, 1 402 cases (75.9%) had complete follow-up data and the median follow-up time was 33.6 (0.1 to 158) months. The 5-year survival rates of extreme low risk, low risk, moderate risk and high risk were 100%, 98.5%, 92.5%, and 79.2% with significant difference(P=0.000).

CONCLUSIONS

Gastric GIST occurs mostly in fundus and body of stomach in China. Wedge excision is the main operational procedure and laparoscopic operation is over 50%. General prognosis of gastric GIST is quite good.