Neoadjuvant versus Postoperative Chemoradiotherapy is Associated with Improved Survival for Patients with Resectable Gastric and Gastroesophageal Cancer.

BACKGROUND: The optimal timing of chemoradiotherapy (CRT) for patients with localized gastric cancer remains unclear. This study aimed to compare the survival outcomes between neoadjuvant and postoperative CRT for patients with gastric and gastroesophageal junction (GEJ) cancer. METHODS: This retrospective study analyzed 152 patients with gastric (42%) or GEJ (58%) adenocarcinoma who underwent definitive surgical resection and received either neoadjuvant or postoperative CRT between 2005 and 2017 at the authors' institution. The primary end point of the study was overall survival (OS). RESULTS: The median follow-up period was 37.5 months. Neoadjuvant CRT was performed for 102 patients (67%) and postoperative CRT for 50 patients (33%). The patients who received neoadjuvant CRT were more likely to be male and to have a GEJ tumor, positive lymph nodes, and a higher clinical stage. The median radiotherapy (RT) dose was 50.4 Gy for neoadjuvant RT and 45.0 Gy for postoperative RT (p < 0.001). The neoadjuvant CRT group had a pathologic complete response (pCR) rate of 26% and a greater rate of R0 resection than the postoperative CRT group (95% vs. 76%; p = 0.002). Neoadjuvant versus postoperative CRT was associated with a lower rate of any grade 3+ toxicity (10% vs. 54%; p < 0.001). The multivariable analysis of OS showed lower hazards of death to be independently associated neoadjuvant versus postoperative CRT (hazard ratio [HR] 0.57; 95% confidence interval [CI] 0.36-0.91; p = 0.020) and R0 resection (HR 0.50; 95% CI 0.27-0.90; p = 0.021). CONCLUSIONS: Neoadjuvant CRT was associated with a longer OS, a higher rate of R0 resection, and a lower treatment-related toxicity than postoperative CRT. The findings suggest that neoadjuvant CRT is superior to postoperative CRT in the treatment of gastric and GEJ cancer.

A study protocol of a randomized phase II trial of perioperative chemoimmunotherapy verses perioperative chemoimmunotherapy plus preoperative chemoradiation for locally advanced gastric (G) or gastroesophageal junction (GEJ) adenocarcinoma: the NeoRacing study.

BACKGROUND: Perioperative chemotherapy (ChT) and preoperative chemoradiation (CRT) are both the standard treatments for locally advanced gastric cancer (LAGC). CRT can achieve a higher pathological complete regression (pCR) rate, but whether this higher pCR rate can be transformed into a long-term survival benefit remains inconclusive. Therefore, relevant studies are in progress. On the other hand, immunotherapy has been established for the first-line treatment of advanced gastric cancer (AGC) and has been widely explored in the perioperative setting. The combination of chemotherapy/radiotherapy and immunotherapy may have a synergistic effect, which will lead to a better antitumor effect. The preliminary reports of ongoing studies show promising results, including a further improved pCR rate. However, the preferred treatment combination for LAGC is still not established. To solve this problem, we are carrying out this randomized phase II trial, which aims to evaluate the efficacy and safety of perioperative chemotherapy plus the use of PD-1 antibody with or without preoperative chemoradiation for LAGC. METHODS: Eligible patients with LAGC or gastroesophageal junction (GEJ) adenocarcinoma were randomized to receive perioperative ChT, PD-1 antibody, surgery with (Arm A) or without preoperative CRT (Arm B), and PD-1 antibody maintenance until one year after surgery. The primary endpoint of this study is that the pCR rate of Arm A will be significantly higher than that of Arm B. The secondary endpoints include the pathological partial regression (pPR) rate, R0 resection rate, objective response rate (ORR), event-free survival (EFS), overall survival (OS), safety and surgical complications. Moreover, several explorative endpoints will be evaluated to find and validate the predictive biomarkers of immunotherapy. DISCUSSION: The results of the NeoRacing study will provide important information concerning the application of PD-1 antibody in LAGC patients during the perioperative setting. Meanwhile, the two treatment protocols will be compared in terms of efficacy and safety. TRIAL REGISTRATION: ClinicalTrials.gov , NCT05161572 . Registered 17 December 2021 - Retrospectively registered.

Prognostic significance of tumor deposits in radically resected gastric cancer: a retrospective study of a cohort of 1915 Chinese individuals.

BACKGROUND: Tumor deposits (TDs) have been identified as an independent prognostic factor in gastric cancer (GC). However, the associated clinicopathological factors and how to simply and reasonably incorporate TD into the TNM staging system remain undetermined. The aim of the current study was therefore to assess the significance of TD among radically resected GC patients. METHODS: We retrospectively reviewed 1915 patients undergoing radical resection between 2007 and 2012. The patients were classified into two groups according to TD status (absent vs. present), and the clinicopathologic characteristics, DFS, and OS were compared. Associations of TD presence with other clinicopathologic factors were evaluated by logistic regression analysis. Univariate and multivariate Cox regression analyses were performed to determine the prognostic factors for DFS and OS in the primary cohort. Propensity score matching (PSM) was performed to reduce the possibility of selection bias according to the presence of TD. External validation of previously proposed modified staging systems incorporating TD was conducted. RESULTS: The detection rate of TD was 10.5% (201/1915). The presence of TD was significantly related to unfavorable clinicopathologic variables, including advanced T and N categories. According to the multivariate Cox regression analysis, the presence of TD was identified as an independent prognostic factor for DFS and OS in the primary cohort (both P < 0.001). In the after-PSM cohort, TD presence also significantly shortened DFS and OS. In the external validation, one system that incorporated TD into the pTNM stage had the best performance. CONCLUSIONS: The presence of TD was significantly associated with poor survival in radically resected GC patients. The incorporation of TD into the TNM staging system can further improve the predictive capability. A multicenter cohort with a large sample size is needed to determine the appropriate method of incorporation.

A Novel Small Molecular Prostaglandin Receptor EP4 Antagonist, L001, Suppresses Pancreatic Cancer Metastasis.

Metastatic pancreatic cancer remains a major clinical challenge, emphasizing the urgent need for the exploitation of novel therapeutic approaches with superior response. In this study, we demonstrate that the aberrant activation of prostaglandin E2 (PGE2) receptor 4 (EP4) is a pro-metastatic signal in pancreatic cancer. To explore the therapeutic role of EP4 signaling, we developed a potent and selective EP4 antagonist L001 with single-nanomolar activity using a panel of cell functional assays. EP4 antagonism by L001 effectively repressed PGE2-elicited cell migration and the invasion of pancreatic cancer cells in a dose-dependent manner. Importantly, L001 alone or combined with the chemotherapy drug gemcitabine exhibited remarkably anti-metastasis activity in a pancreatic cancer hepatic metastasis model with excellent tolerability and safety. Mechanistically, EP4 blockade by L001 abrogated Yes-associated protein 1 (YAP)-driven pro-metastatic factor expression in pancreatic cancer cells. The suppression of YAP's activity was also observed upon L001 treatment in vivo. Together, these findings support the notions that EP4-YAP signaling axis is a vital pro-metastatic pathway in pancreatic cancer and that EP4 inhibition with L001 may deliver a therapeutic benefit for patients with metastatic pancreatic cancer.

Study protocol of a randomized phase III trial of comparing preoperative chemoradiation with preoperative chemotherapy in patients with locally advanced gastric cancer or esophagogastric junction adenocarcinoma: PREACT.

BACKGROUND: The prognosis of patients with locally advanced gastric cancer or esophagogastric junction adenocarcinoma is still dismal. There are no standard treatment strategies for these patients. Multidisciplinary team (MDT) approach is a good choice for making a high-quality decision. Generally, MDT will recommend these patients to receive preoperative chemotherapy or preoperative chemoradiation based on all kinds of treatment guidelines. However, the preferred preoperative treatment is still not established. In order to solve this problem, we carry out this randomized phase III trial of comparing preoperative chemoradiation with preoperative chemotherapy in patients with locally advanced gastric cancer or esophagogastric junction adenocarcinoma. METHODS: Eligible patients with locally advanced gastric cancer or esophagogastric junction adenocarcinoma are randomized to receive preoperative chemoradiation or preoperative chemotherapy, followed by surgery and postoperative chemotherapy. In the preoperative chemoradiation arm (Pre-CRT), patients receive two cycles of S-1 and oxaliplatin (SOX), chemoradiation, then followed by surgery and three more cycles of SOX chemotherapy. In the preoperative chemotherapy arm (Pre-CT), patients receive three cycles of SOX, following surgery three more cycles of SOX are given. The primary endpoint of this trial is to verify that preoperative chemoradiation could significantly improve the 3-year disease free survival (DFS) of patients with locally advanced gastric cancer or esophagogastric junction adenocarcinoma compared to preoperative chemotherapy. DISCUSSION: The results from this trial will provide important information about whether preoperative chemoradiation could improve survival compared to preoperative chemotherapy among patients with locally advanced gastric cancer or esophagogastric junction adenocarcinoma. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03013010. First posted January 6, 2017.

Phase II trial of preoperative chemoradiation plus perioperative SOX chemotherapy in patients with locally advanced gastric cancer.

BACKGROUND AND PURPOSE: The ideal treatment strategy of patients with locally advanced gastric adenocarcinoma is unclear. The aim of this study is to evaluate the efficacy and feasibility of preoperative chemoradiation in these patients. PATIENTS AND METHODS: All patients underwent laparoscopic exploration or exploratory laparotomy before chemoradiation. Patients received one cycle of S-1 and oxalipatin followed by concurrent radiation and chemotherapy, then underwent another cycle of S-1 and oxalipatin. Surgery was performed 6-8 weeks after completing radiochemotherapy. The rate of curative gastrectomy and survival were investigated. This trial was registered with ClinicalTrial.gov, number NCT02024217. RESULTS: From April 2012 to August 2014, 40 patients were enrolled in the trial, and 36 patients were assessable. The most common hematologic toxic effects were leukopenia (80.6%), neutropenia (69.4%), and thrombocytopenia (50%); the most common nonhematologic toxic effects were anorexia (50%), nausea (22.3%), and vomiting (13.9%). There were no treatment related deaths. A total of 33 patients underwent second exploratory laparotomy after preoperative chemoradiation, and 24 (67%) patients received curative gastrectomy. The rates of pathological complete response (pCR) were 13.9%. The medial survival time (MST) was 30.3 months. CONCLUSION: Preoperative chemoradiation may be an effective treatment strategy among patients with locally advanced gastric adenocarcinoma.

Postoperative chemoradiotherapy versus chemotherapy for R0 resected gastric cancer with D2 lymph node dissection: an up-to-date meta-analysis.

BACKGROUND: This meta-analysis aims to provide more evidence on the role of postoperative chemoradiotherapy (CRT) for gastric cancer (GC) patients in Asian countries where D2 lymphadenectomy is prevalent. METHODS: We conducted a systematic review of randomized controlled trials (RCTs), extracted data of survival and toxicities, and pooled data to evaluate the efficacy and toxicities of CRT compared with chemotherapy (CT) after D2 lymphadenectomy. RESULTS: A total of 960 patients from four RCTs were selected. The results showed that postoperative CRT significantly reduced loco-regional recurrence rate (LRRR: RR = 0.50, 95 % CI = 0.34-0.74, P = 0.0005) and improved disease-free survival (DFS: HR = 0.73, 95 % CI = 0.60-0.89, P = 0.002). However, CRT did not affect distant metastasis rate (DMR: RR = 0.81, 95 % CI = 0.60-1.08, P = 0.15) and overall survival (OS: HR = 0.91, 95 % CI = 0.74-1.11, P = 0.34). The main grade 3-4 toxicities manifested no significant differences between the two groups. CONCLUSIONS: Overall, CRT after D2 lymphadenectomy may reduce LRRR and prolong DFS. The role of postoperative CRT should be further investigated in the population with high risk of loco-regional recurrence.

Radiomics of skeletal muscle helps to predict gastrointestinal toxicity in locally advanced rectal cancer patients receiving neoadjuvant chemoradiotherapy.

Background: The skeletal muscle index (SMI) can serve as a surrogate for a patient's nutritional status, which is associated with treatment toxicity. This study aims to investigate the potential of baseline skeletal muscle radiomics features to predict gastrointestinal toxicity of neoadjuvant chemoradiotherapy for rectal cancer. Methods: A total of 214 rectal cancer patients (115, 49 and 50 in the training, internal and external validation set, respectively) who underwent neoadjuvant pelvic radiotherapy with capecitabine and irinotecan were retrospectively identified. The skeletal muscle at the level of the third lumber vertebra was contoured, and the radiomics features were extracted from computed tomography scans. In the training set, the least absolute shrinkage and selection operator (LASSO) regression algorithm was applied to select features that were most significantly associated with grade 3-4 gastrointestinal toxicity (diarrhea, nausea, vomiting and proctitis). The predictive performance and clinical utility were estimated using the area under the receiver operator characteristic curve (AUC), F1-score and decision curve analysis (DCA). Results: Nine features, including the SMI and eight radiomics features, were associated with grade 3-4 gastrointestinal toxicity and included in the logistic regression. This combined predictive model, which incorporated the SMI and radiomics features, showed better discrimination than the SMI alone, with an AUC of 0.856 (95 % CI: 0.782-0.929) in the training cohort, 0.812 (95 % CI: 0.667-0.956) in the internal validation cohort and 0.745 (95 % CI: 0.600-0.890) in the external validation cohort. DCA further verified the clinical utility of the combined predictive model. Conclusion: Radiomics features of skeletal muscle were significantly associated with gastrointestinal toxicity. The predictive model incorporating the SMI and radiomics features exhibits favorable discrimination and may be highly informative for clinical decision-makings.

Radiomic score for lung nodules as a prognostic biomarker in locally advanced rectal cancer patients: A bi-institutional study.

BACKGROUND: Undetermined lung nodules are common in locally advanced rectal cancer (LARC) and lack precise risk stratification. This study aimed to develop a radiomic-based score (Rad-score) to distinguish metastasis and predict overall survival (OS) in patients with LARC and lung nodules. METHODS: Retrospective data from two institutions (July 10, 2006-September 24, 2015) was used to develop and validate the Rad-score for distinguishing lung nodule malignancy. The prognostic value of the Rad-score was investigated in LARC cohorts, leading to the construction and validation of a clinical and radiomic score (Cli-Rad-score) that incorporates both clinical and radiomic information for the purpose of improving personalized clinical prognosis prediction. Descriptive statistics, survival analysis, and model comparison were performed to assess the results. RESULTS: The Rad-score demonstrated great performance in distinguishing malignancy, with C-index values of 0.793 [95% CI: 0.729-0.856] in the training set and 0.730 [95% CI: 0.666-0.874] in the validation set. In independent LARC cohorts, Rad-score validation achieved C-index values of 0.794 [95% CI: 0.737-0.851] and 0.747 [95% CI: 0.615-0.879]. Regarding prognostic prediction, Rad-score effectively stratified patients. Cli-Rad-score outperformed the clinicopathological information alone in risk stratification, as evidenced by significantly higher C-index values (0.735 vs. 0.695 in the internal set and 0.618 vs. 0.595 in the external set). CONCLUSIONS: CT-based radiomics could serve as a reliable and powerful tool for lung nodule malignancy distinction and prognostic prediction in LARC patients. Rad-score predicts prognosis independently. Incorporation of Cli-Rad-score significantly enhances the persionalized clinical prognostic capacity in LARC patients with lung nodules.

The advantage of circulating tumor cells over serum carcinoembryonic antigen for predicting treatment responses in rectal cancer.

AIM: The objective of this study was to investigate the clinical significance of circulating tumor cells (CTCs) on the evaluation and prediction of treatment responses in rectal cancer patients compared with serum carcinoembryonic antigen (CEA). MATERIALS & METHODS: Both CTCs and CEA levels of 103 rectal cancer patients (66 with stage II-III and 37 with recurrence or metastasis) were analyzed before and after chemoradiotherapy. CTCs were detected using EpCAM magnetic bead-based enrichment combined with cytometric identification. RESULTS: CTCs were detected in all patients while no tumor cells were found in healthy controls. CTC levels in metastatic patients were significantly higher than those with recurrence or stage II-III rectal cancer. There is a close relationship between CTC levels and treatment outcomes but serum CEA did not have any correlation. CONCLUSION: CTCs are promising markers for the evaluation and prediction of treatment responses in rectal cancer patients, superior to the conventional tumor marker CEA.

Long-term outcomes in a retrospective cohort of patients with rectal cancer with complete response after total neoadjuvant therapy: a propensity-score weighted analysis.

Background: The watch-and-wait (W&W) strategy is a novel treatment option for patients with rectal cancer who have a strong desire for organ preservation. The study aimed to explore the long-term outcomes of the W&W strategy in a large cohort of rectal cancer patients who achieved a clinical complete response (cCR) after consolidation total neoadjuvant therapy (TNT), and to compare with patients who achieved a pathological complete response (pCR) after radical surgery. Methods: The W&W group comprised patients who were assessed as having a cCR after consolidation TNT and adopted the W&W strategy. Patients who underwent standard resection and achieved a pCR were compared as a reference. Inverse probability of treatment weighting (IPTW)-adjusted Kaplan-Meier analysis with log-rank test was used to compare survival outcomes. Results: We included 89 and 171 patients in the W&W and pCR groups, respectively. The median follow-up period was 45 and 58 months for the W&W and pCR groups, respectively. After IPTW adjustment, the 2-year local regrowth/recurrence rate for the W&W and pCR groups were 9.9% and 2.0%, respectively (p < 0.001). The W&W and pCR groups had similar 5-year outcomes, including overall survival, disease-free survival, and distant metastasis-free survival (all p > 0.05). No significant difference was observed in the rates of distant metastasis between patients in the W&W group with local regrowth and those without local regrowth (25% versus 6.2%, p = 0.119). Conclusion: Patients who were managed with a W&W strategy after consolidation TNT had favorable survival outcomes, which were similar to those of patients with a pCR. The rate of local regrowth in W&W patients was lower in our study than in other studies as a result of the implementation of consolidation TNT.

A real-time respiration position based passive breath gating equipment for gated radiotherapy: a preclinical evaluation.

PURPOSE: To develop a passive gating system incorporating with the real-time position management (RPM) system for the gated radiotherapy. METHODS: Passive breath gating (PBG) equipment, which consists of a breath-hold valve, a controller mechanism, a mouthpiece kit, and a supporting frame, was designed. A commercial real-time positioning management system was implemented to synchronize the target motion and radiation delivery on a linear accelerator with the patient's breathing cycle. The respiratory related target motion was investigated by using the RPM system for correlating the external markers with the internal target motion while using PBG for passively blocking patient's breathing. Six patients were enrolled in the preclinical feasibility and efficiency study of the PBG system. RESULTS: PBG equipment was designed and fabricated. The PBG can be manually triggered or released to block or unblock patient's breathing. A clinical workflow was outlined to integrate the PBG with the RPM system. After implementing the RPM based PBG system, the breath-hold period can be prolonged to 15-25 s and the treatment delivery efficiency for each field can be improved by 200%-400%. The results from the six patients showed that the diaphragm motion caused by respiration was reduced to less than 3 mm and the position of the diaphragm was reproducible for difference gating periods. CONCLUSIONS: A RPM based PBG system was developed and implemented. With the new gating system, the patient's breath-hold time can be extended and a significant improvement in the treatment delivery efficiency can also be achieved.

Are biomarkers correlated with recurrence patterns in patients with resectable gastric adenocarcinoma.

The aims of this study are to analyze the failure patterns in radical resected gastric adenocarcinoma, and to evaluate the correlation between recurrence patterns and potentially prognostic factors, including clinical pathological characteristic and biomarkers. Between Jan 2004 and Jun 2006, 84 patients were enrolled into the database analysis, including 8 with clinical stage I, 20 with clinical stage II, 21 with clinical stage IIIA, 22 with clinical stage IIIB and 13 with clinical stage IV, male 61 and female 23. The collected biomarkers including: preoperative tumor markers: CEA, AFP, CA199, CA50, CA72-4 and CA24-2; postoperative immunohistochemical (IHC) markers: Bax, Bcl-2, P27, CyclinD1, TOPO2, MDR, GST-π, Ki67, epidermal growth factor receptor (EGFR), P21, P53, proliferating cell nuclear antigen (PCNA), C-myc and Neu. Three-year local control rate (LCR), disease-free survival (DFS) and over-all survival (OS) were 66, 61 and 64% respectively. Logistic regression analysis showed cyclinD1 and CEA were correlated with prognosis; cyclinD1, CEA were correlated with loco-regional recurrence; PCNA was correlated with remote metastasis; bcl-2, ki67, c-myc2 and Neu were correlated with lymph node metastasis. The present study indicate that patterns of recurrence are variable and may be associated with specific biomarkers, in addition, high level of CEA and low-expressed of cyclinD1 resulted in poor prognosis.

The role of nutritional assessment for predicting radiotherapy-induced adverse events in patients with gastric cancer.

OBJECTIVE: The aim of this study was to investigate the role of nutritional factors in predicting radiotherapy-associated toxicities for gastric cancer patients. METHODS: A total of 285 gastric cancer patients who underwent radiotherapy in our hospital (Fudan University Shanghai Cancer Center) between 2010 and 2017 were included in this retrospective study. Nutritional status assessment included body weight loss (BWL), body mass index (BMI), serum albumin, nutrition risk screening 2002(NRS-2002), patient-generated subjective global assessment(PG-SGA) and nutritional risk index (NRI). RESULTS: Of all patients, 19.6% were underweight (BMI<18.5 kg/m2), 25.6% were hypoalbuminemia (<35 g l-1) and 48.8% lost ≥10% of body weight in the 6-month interval before radiotherapy(BWL). Meanwhile, 73.3%, 78.6 and 47.2% of the patients were diagnosed as malnutrition based on NRS-2002, PG-SGA and NRI, respectively. Hematological adverse events were present in 91.2% (≥Grade 1) and 20.4% (≥Grade 3) of the patients. Non-hematological adverse events occurred in 89.8% (≥Grade1) and 14.4% (≥Grade 3) of the patients. Multivariate analyses indicated that only hypoalbuminemia(<35 g l-1) was independent predictor for Grade 3/4 hematological and non-hematological adverse events. Meanwhile, higher BWL(≥10%) was also independent predictor for Grade 3/4 non-hematological adverse events. NRS-2002, PG-SGA and NRI score were not associated with treatment-induced adverse events. CONCLUSION: BWL and serum albumin are useful factors for predicting severe adverse events in gastric cancer patients who undergo radiotherapy. ADVANCES IN KNOWLEDGE: The use of nutritional factors in predicting severe adverse events enables implementation of individualized treatment strategies for early and intensive nutritional interventions in high-risk patients.

Pangenomic analysis of Chinese gastric cancer.

Pangenomic study might improve the completeness of human reference genome (GRCh38) and promote precision medicine. Here, we use an automated pipeline of human pangenomic analysis to build gastric cancer pan-genome for 185 paired deep sequencing data (370 samples), and characterize the gene presence-absence variations (PAVs) at whole genome level. Genes ACOT1, GSTM1, SIGLEC14 and UGT2B17 are identified as highly absent genes in gastric cancer population. A set of genes from unaligned sequences with GRCh38 are predicted. We successfully locate one of predicted genes GC0643 on chromosome 9q34.2. Overexpression of GC0643 significantly inhibits cell growth, cell migration and invasion, cell cycle progression, and induces cell apoptosis in cancer cells. The tumor suppressor functions can be reversed by shGC0643 knockdown. The GC0643 is approved by NCBI database (GenBank: MW194843.1). Collectively, the robust pan-genome strategy provides a deeper understanding of the gene PAVs in the human cancer genome.

Immune Score Predicts Outcomes of Gastric Cancer Patients Treated with Adjuvant Chemoradiotherapy.

BACKGROUND: Substantial evidence has demonstrated that tumor-infiltrating lymphocytes (TILs) are correlated with patient prognosis. The TIL-based immune score (IS) affects prognosis in various cancers, but its prognostic impact in gastric cancer (GC) patients treated with adjuvant chemoradiotherapy remains unclear. METHODS: A total of 101 GC patients who received chemoradiotherapy after gastrectomy were retrospectively analyzed in this study. Immunohistochemistry staining for CD3+ and CD8+ T-cell counts in both tumor center (CT) and invasive margin (IM) regions was built into the IS. Patients were then divided into three groups based on their differential IS levels. The correlation between IS and clinical parameters was analyzed. The prognostic impact of IS and clinical parameters was evaluated using Kaplan-Meier analysis and Cox proportional hazard regression analysis. Receiver operating characteristic (ROC) curves were plotted to compare the area under the curve (AUC) of IS with other clinical parameters. Nomograms for disease-free survival (DFS) and overall survival (OS) prediction were constructed based on the identified parameters. RESULTS: Finally, 20 (19.8%), 57 (56.4%), and 24 (23.8%) GC patients were identified with low, intermediate, and high IS levels, respectively. GC patients with higher IS levels exhibited better DFS (p < 0.001) and OS (p < 0.001). IS was an independent prognostic factor for both DFS (p < 0.001) and OS (p < 0.001) in multivariate analysis. IS presented a better predictive ability than the traditional pathological tumor-node-metastasis (pTNM) staging system (AUC: 0.801 vs. 0.677 and 0.800 vs. 0.660, respectively) with respect to both DFS and OS. The C-index of the nomograms for DFS and OS prediction was 0.737 and 0.774, respectively. CONCLUSIONS: IS is a strong predictive factor for both DFS and OS in GC patients treated with adjuvant chemoradiotherapy, which may complement the traditional pTNM staging system.

Antitumor Effect of Cycle Inhibiting Factor Expression in Colon Cancer via Salmonella VNP20009.

BACKGROUND: Colon cancer is one of the major causes of morbidity and mortality worldwide. Cycle inhibiting factors (Cifs) have been shown to deamidate Nedd8, resulting in cell cycle arrest. OBJECTIVE: To determine the antitumor effect of Cifs on colon cancer by using attenuated Salmonella typhimurium VNP20009. METHODS: The VNP-SOPE2-cif and VNP-SOPE2-cif-C/A plasmids were transfected into attenuated Salmonella typhimurium VNP20009. The efficiency and specificity of the Cif promoter were validated in colon cancer SW480 cell lines. Western blotting was subsequently performed to evaluate cell cycle regulators, including P21, P27 and Wee1. In vivo, the antitumor effect of VNP20009 was evaluated in a colon cancer xenograft model. RESULTS: Firstly, VNP-SOPE2-cif and VNP-SOPE2-cif-C/A were selectively expressed both in the bacterial and colon cancer cells. Cif expression in SW480 cells via the VNP tumor-targeted expression system induced the accumulation of Wee1, p21 and p27 expression. Moreover, tumor growth was significantly inhibited in the mice with VNP-SOPE2-cif compared to the mice with VNP with the empty construct. CONCLUSION: These results suggest that Cif gene delivered by VNP20009 is a promising approach for the treatment of colon cancer.