Different risks of nodal metastasis by tumor location in remnant gastric cancer after curative gastrectomy for gastric cancer

Silencing circ_0043256 inhibited CoCl2-induced proliferation, migration, and aerobic glycolysis in gastric cancer cells

We aimed to explore the role of circular RNA 0043256 (circ_0043256) in gastric cancer (GC) and its underlying mechanisms. The impact of circ_0043256 silencing on the proliferation, migration, apoptosis, and aerobic glycolysis of MKN-45 and AGS cells induced by CoCl2 was assessed through the utilization of CCK-8, wound healing assay, flow cytometry, and metabolic analysis. The interaction between circ_0043256 and miR-593-5p, as well as the involvement of the miR-593-5p/RRM2 axis in gastric cancer, were confirmed via luciferase assay, Western blot, and bioinformatics analysis. We found that circ_0043256 was up-regulated in GC tissues and CoCl2-treated MKN-45 and AGS cells. Silencing of circ_0043256 reversed CoCl2-induced proliferation, migration, and aerobic glycolysis in MKN-45 and AGS cells. Additionally, circ_0043256 silencing enhanced cell apoptosis and G2/M phase cell cycle arrest in response to CoCl2 treatment. Furthermore, the miR-593-5p/RRM2 axis was identified as a regulatory mechanism for circ_0043256 function in GC. Silencing of circ_0043256 and miR-593-5p mimic co-transfection significantly inhibited CoCl2-induced cellular responses in MKN-45 and AGS cells. A glycolysis inhibitor 2-DG further enhanced the inhibitory effect of circ_0043256 silencing on aerobic glycolysis of CoCl2-induced MKN-45 and AGS cells. Additionally, the inhibition of circ_0043256 resulted in a reduction in tumor volume and the expression of proliferation marker proteins in nude mice. Moreover, the suppression of circ_0043256 led to an increase in miR-593-5p expression and a decrease in RRM2 expression, ultimately causing a decrease in glycolytic-related proteins associated with the glycolytic pathway. Targeting this axis may offer a novel therapeutic approach for treating GC.

Microfluidic printed 3D bioactive scaffolds for postoperative treatment of gastric cancer

Tumor recurrence and tissue regeneration are two major challenges in the postoperative treatment of cancer. Current research hotspots are focusing on developing novel scaffold materials that can simultaneously suppress tumor recurrence and promote tissue repair. Here, we propose a microfluidic 3D-printed methacrylate fish gelatin (F-GelMA@BBR) scaffold loaded with berberine (BBR) for the postoperative treatment of gastric cancer. The F-GelMA@BBR scaffold displayed a significant killing effect on gastric cancer MKN-45 cells in vitro and demonstrated excellent anti-recurrence efficiency in gastric cancer postoperative models. In vitro experiments have shown that F-GelMA@BBR exhibits significant cytotoxicity on gastric cancer cells while maintaining the cell viability of normal cells. The results of in vivo experiments show that F-GelMA@BBR can significantly suppress the tumor volume to 49.7 % of the control group. In addition, the scaffold has an ordered porous structure and good biocompatibility, which could support the attachment and proliferation of normal cells to promote tissue repair at the tumor resection site. These features indicated that such scaffold material is a promising candidate for postoperative tumor treatment in the practical application.

The epigenetic modifier lysine methyltransferase 2C is frequently mutated in gastric remnant carcinoma

Gastric remnant carcinoma (GRC), which occurs in the stomach after partial gastrectomy, is a rare and aggressive form of gastric adenocarcinoma (GAC). Comprehensive profiling of genomic mutations in GRC could provide the basis for elucidating the origin and characteristics of this cancer. Herein, whole-exome sequencing (WES) was performed on 36 matched tumor-normal samples from patients with GRC and identified recurrent mutations in epigenetic modifiers, notably KMT2C, ARID1A, NSD1, and KMT2D, in 61.11% of cases. Mutational signature analysis revealed a low frequency of microsatellite instability (MSI) in GRC, which was further identified by MSIsensor, MSI-polymerase chain reaction, and immunohistochemistry analysis. Comparative analysis demonstrated that GRC had a distinct mutation spectrum compared to that of GAC in The Cancer Genome Atlas samples, with a significantly higher mutation rate of KMT2C. Targeted deep sequencing (Target-seq) of an additional 25 paired tumor-normal samples verified the high mutation frequency (48%) of KMT2C in GRC. KMT2C mutations correlated with poor overall survival in both WES and Target-seq cohorts and were independent prognosticators in GRC. In addition, KMT2C mutations were positively correlated with favorable outcomes in immune checkpoint inhibitor-treated pan-cancer patients and associated with higher intratumoral CD3+ , CD8+ tumor-infiltrating lymphocyte counts, and PD-L1 expression in GRC samples (p = 0.018, 0.092, 0.047, 0.010, and 0.034, respectively). Our dataset provides a platform for information and knowledge mining of the genomic characteristics of GRC and helps to frame new therapeutic approaches for this disease.

Evaluating the optimal treatment strategy for early and advanced remnant gastric cancer

BACKGROUND

This study assessed lymph node metastasis characteristics to investigate the optimal treatment strategy for early and advanced remnant gastric cancer (RGC).

METHODS

Cases of completion gastrectomy for RGC were enrolled. The frequency of lymph node metastasis was investigated, and risk factors for metastasis were identified. The clinical significance of completion gastrectomy in early remnant gastric carcinoma cases was also examined. In advanced cases, 3-year survival was analysed to investigate the prognostic importance of lymph node dissection and splenectomy.

RESULTS

Seventy-nine patients were included. Lymphatic invasion and pathological tumour depth were identified as risk factors for lymph node metastasis. There was no metastasis in the pT1 cases. In advanced cases, the incidence of lymph node #10 and jejunal lymph node metastasis was 8.3-10.0% and 17.6%, respectively. Prognosis was found to be unrelated with splenectomy.

CONCLUSIONS

Lymphatic invasion and pathological T status were identified as risk factors for LN metastasis in RGC. Additional gastrectomy after ESD might not be mandatory for early RGC cases. For advanced RGC cases, splenectomy might not improve patient prognosis, however, lymph node dissection of jejunal and #10 lymph nodes should be considered due to its high incidence of metastasis.

Tumor Location Causes Different Recurrence Patterns in Remnant Gastric cancer

Purpose

Tumor recurrence is the principal cause of poor outcomes in remnant gastric cancer (RGC) after resection. We sought to elucidate the recurrent patterns according to tumor locations in RGC.

Materials and Methods

Data were collected from the Shanghai Cancer Center between January 2006 and December 2020. A total of 129 patients with RGC were included in this study, of whom 62 had carcinomas at the anastomotic site (group A) and 67 at the non-anastomotic site (group N). The clinicopathological characteristics, surgical results, recurrent diseases, and survival were investigated according to tumor location.

Results

The time interval from the previous gastrectomy to the current diagnosis was 32.0±13.0 and 21.0±13.4 years in groups A and N, respectively. The previous disease was benign in 51/62 cases (82.3%) in group A and 37/67 cases (55.2%) in group N (P=0.002). Thirty-three patients had documented sites of tumor recurrence through imaging or pathological examinations. The median time to recurrence was 11.0 months (range, 1.0–35.1 months). Peritoneal recurrence occurred in 11.3% (7/62) of the patients in group A versus 1.5% (1/67) of the patients in group N (P=0.006). Hepatic recurrence occurred in 3.2% (2/62) of the patients in group A versus 13.4% (9/67) of the patients in group N (P=0.038). Patients in group A had significantly better overall survival than those in group N (P=0.046).

Conclusions

The tumor location of RGC is an essential factor for predicting recurrence patterns and overall survival. When selecting an optimal postoperative follow-up program for RGC, physicians should consider recurrent features according to the tumor location.

Safety and feasibility of laparoscopic gastrectomy for remnant gastric cancer compared with open gastrectomy: Single-center experience

The usefulness, safety and oncological validity of laparoscopic gastrectomy (LG) for remnant gastric cancer (RGC) have not been widely reported.A total of 38 patients who underwent gastrectomy for RGC were enrolled at Wakayama Medical University Hospital between April 2008 and December 2018. All consecutive patients were included in this retrospective study; the patients were divided into the open gastrectomy group and the laparoscopic group according to the sequential nature of their operation. Fifteen patients underwent open gastrectomy for RGC (OGR) between April 2008 and December 2013, and 23 patients underwent LG for RGC (LGR) after 2014.In the OGR group, all initial operations were performed by open surgery, whereas in the LGR group, 11 patients (47%) initially underwent laparoscopic surgery and 12 patients (53%) initially underwent open surgery (P = .002), 3 patients of which (25%) converted to open gastrectomy. There was no significant difference in the number of lymph node dissections or in operative time between the 2 groups, but blood loss was significantly lower in the LGR group than that in the OGR group (P = .002). Furthermore, although there was no difference between the 2 groups in C-reactive protein value on postoperative day 1, C-reactive protein value on postoperative day 3 was significantly lower in the LGR group than in the OGR group (P = .012). There were no differences in postoperative complications or long-term outcomes, including recurrence-free survival and overall survival.LGy is suitable in cases in which the initial surgery is performed by laparoscopic surgery. Even if the initial surgery is open surgery, it is oncologically equivalent to open gastrectomy and can be performed safely with less blood loss.