Postoperative chemoradiotherapy in gastric cancer: a phase I study of radiotherapy with dose escalation of oxaliplatin, 5-fluorouracil, and leucovorin (FOLFOX regimen)

Effect of cetuximab plus FOLFOX4 regimen on clinical outcomes in advanced gastric carcinoma patients receiving evidence-based care

BACKGROUND

Although chemotherapy is effective for treating advanced gastric carcinoma (aGC), it may lead to an adverse prognosis. Establishing a highly effective and low-toxicity chemotherapy regimen is necessary for improving efficacy and outcomes in aGC patients.

AIM

To determine the efficacy and safety of cetuximab (CET) combined with the FOLFOX4 regimen (infusional fluorouracil, folinic acid, and oxaliplatin) as first-line therapy for patients with aGC, who received evidence-based care (EBC).

METHODS

A total of 117 aGC patients who received EBC from March 2019 to March 2022 were enrolled. Of these, 60 in the research group (RG) received CET + FOLFOX4 as first-line therapy, whereas 57 in the control group (CG) received FOLFOX4. The efficacy [clinical response rate (RR) and disease control rate (DCR)], safety (liver and kidney dysfunction, leukopenia, thrombocytopenia, rash, and diarrhea), serum tumor marker expression [STMs; carbohydrate antigen (CA) 19-9, CA72-4, and carcinoembryonic antigen (CEA)], inflammatory indicators [interleukin (IL)-2 and IL-10], and quality of life (QOL) of the two groups were compared.

RESULTS

A markedly higher RR and DCR were observed in the RG compared with the CG, with an equivalent safety profile between the two groups. RG exhibited notably reduced CA19-9, CA72-4, CEA, and IL-2 levels following treatment, which were lower than the pre-treatment levels and those in the CG. Post-treatment IL-10 was statistically increased in RG, higher than the pre-treatment level and the CG. Moreover, a significantly improved QOL was evident in the RG.

CONCLUSION

The CET + FOLFOX4 regimen is highly effective as first-line treatment for aGC patients receiving EBC. It facilitates the suppression of STMs, ameliorates the serum inflammatory microenvironment, and enhances QOL, without increased adverse drug effects.

Expression Status And Prognostic Value Of M6A-associated Genes in Gastric Cancer

Purpose: Gastric cancer (GC) is a primary cause of cancer-associated mortality worldwide. N6-methyladenosine (m6A) is one of the most common RNA modifications that involves in the progression of numerous cancers. However, the expression status and function of m6A-related genes in gastric cancer is still not well understood. The current study is aimed to investigate the expression status and determinate prognostic value of m6A-related genes in gastric cancer.

Methods: m6A-asssociated gene expression was evaluated via analyzing the expression data of GC patients from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. The protein expression levels of m6A-associated molecules were further validated by immunohistochemical (IHC) staining data from GC tissue microarray (TMA) cohort and Human Protein Atlas (HPA) database. Kaplan-Meier analysis was performed to assess the prognostic value of m6A-associated genes in gastric cancer. Risk score model was established by lasso COX regression analysis and its prognostic predicted efficiency was assessed by the receiver-operator characteristic (ROC) curve. Cox regression analyses were used for exploring risk factors related to GC patient prognosis.

Results: Most of m6A-related genes were upregulated at both mRNA and protein levels in gastric cancer tissues compared with that in normal gastric tissues. The expression levels of m6A-related genes were associated with clinicopathological features including race, age and TNM stage. High expression of WTAP and FTO predicted poor prognosis of GC patients. Survival analysis demonstrated that patients with high-risk scores had worse overall survival (OS) and ROC curves suggested the prediction performance for gastric patients. Moreover, Cox regression analyses indicated that m6A risk model score was a prognostic factor for OS and FTO upregulation might be a potential independent prognostic factor for recurrence-free survival (RFS) in gastric cancer patients.

Conclusion: m6A-related genes were dysregulated in GC and were closely associated with prognosis of GC patients. FTO might serve as a novel prognostic biomarker for gastric cancer, while the m6A-related risk score might be informative for risk assessment and prognostic stratification.

A miR-567-PIK3AP1-PI3K/AKT-c-Myc feedback loop regulates tumour growth and chemoresistance in gastric cancer

Background

Gastric cancer (GC) ranks the fifth most common cancer, and chemotherapy is one of the most common treatments for GC. However, chemoresistance limits the effectiveness of chemotherapy and leads to treatment failure. This study aims to investigate the biological effect of miR-567 on gastric tumourigenesis and chemoresistance and reveal the possible mechanism.

Methods

We measured the expression of miR-567 in 37 paired normal and stomach tumour specimens, as well as GC cell lines by Real-time PCR. The functional effects of miR-567 were validated using in vitro and in vivo assays. Dual-luciferase report assays and Chromatin immunoprecipitation (ChIP) assay were conducted for target evaluation, western blot assay was used to confirm the relationships.

Findings

Our data showed that miR-567 was downregulated in gastric tissues and gastric cancer cells compared with normal tissues and gastric epithelial cells. In vitro, Gain- and lose-of-function assays showed miR-567 not only weakened cells proliferative ability, but also sensitized GC cells to 5-FU and oxaliplatin. In vivo, miR-567 overexpression significantly repressed the tumourigenesis of GC cells compared with the vector control. Mechanistic analysis showed that PIK3AP1 activated AKT phosphorylation in GC. Meanwhile, miR-567 directly targeted PIK3AP1 to inactivate PI3K/AKT/c-Myc pathway and c-Myc inversely regulated miR-567 expression, thus forming a miR-567-PIK3AP1- PI3K/AKT-c-Myc feedback loop explaining the function of miR-567.

Interpretation

Our studies revealed that miR-567 acts as a tumour suppressor gene and suppresses GC tumorigenesis and chemoresistance via a miR-567-PIK3AP1- PI3K/AKT-c-Myc feedback loop. These results suggest that miR-567 may serve as a target for chemoresistance and a potential prognostic biomarker for GC.

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miR-567 sensitized GC cells to 5-FU and oxaliplatin, suggesting that it can be a target for chemoresistance.

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miR-567 functions as a suppressor in GC progression and may serve as a novel prognostic and therapeutic biomarker for GC.

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miR-567 directly targeted PIK3AP1 to inactivate PI3K/AKT/c-Myc and regulated its own expression.

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These findings uncover a plausible mechanism for AKT/PI3K signalling activation in cancer progression.

Two postoperative chemotherapies for gastric cancer: FOLFOX4 vs. TPF

Clinical effects of FOLFOX4 and TPF chemotherapy regimen on postoperative gastric cancer patients were investigated. A total of 60 patients admitted to the First People's Hospital of Changzhou receiving gastric cancer operation were selected and they were divided into two groups at random. Thirty patients in the FOLFOX4 group were treated with oxaliplatin, fluorouracil and leucovorin, while 30 patients in the TPF group were treated with paclitaxel, fluorouracil and cisplatin. The therapeutic effects, adverse reactions, quality of life and survival time of patients in the two groups were observed. The total effective rate of the FOLFOX4 group was 73.3%, which was significantly higher than that of the TPF group (43.3%), and the difference was statistically significant (P<0.05). The proportions of neurotoxicity and thrombocytopenia in the FOLFOX4 group were 56.7 and 33.3%, while those in the TPF group were 26.7 and 60%, respectively, and the differences were statistically significant (P<0.05). The increasing proportion of postoperative scores of the FOLFOX4 group was 46.7%, which was significantly higher than that of the TPF group (20%), and the difference was statistically significant (P<0.05). The 2- and 3-year survival rates of the FOLFOX4 group were 63.3 and 50%, which were significantly higher than those of the TPF group (36.7 and 23.3%), and the differences were statistically significant (P<0.05). Therefore, the effective rate of FOLFOX4 regimen is high in the treatment of gastric cancer with relatively fewer adverse reactions, which has a certain advantage.

The prognostic value of lymph node ratio for local advanced gastric cancer patients with adjuvant chemoradiotherapy after D2 gastrectomy

This study aimed to find the prognostic factors of local advanced gastric cancer patients with adjuvant concurrent chemoradiotherapy after radical D2 gastrectomy, and explore the prognostic value of lymph node ratio (LNR).We retrospectively analyzed 164 gastric cancer patients enrolled in West China Hospital from 2006 to 2013, who underwent D2 radical gastrectomy and adjuvant chemoradiotherapy. With univariate analysis and the Cox regression model, we evaluated the association of LNR and other clinical pathological characteristics with overall survival (OS) and relapse-free survival (RFS) of patients.Of 164 gastric cancer patients, the median age at diagnosis was 60 (IQR 51-66), with 121 males (73.78%) and 43 females (26.22%). The median follow-up time was 41.5 months. One-year and 3-year OS rate of the whole cohort was 97.6% and 88.4%, with 1-year RFS rate of 90.2% and 3-year RFS rate of 76.8%, respectively. In the univariate analysis, we found that age >60years (P = .025), TNM stage III (P = .014), LNR >0.25 (P = .006) and radiation dose <45Gy (P = .048) predicted worse OS. Further multivariate analysis indicated that age >60y (HR 2.375, 95% CI 1.100-5.128; P = .028), TNM stage III (HR 7.692, 95% CI 1.009-58.824; P = .049) and LNR >0.25 (HR 2.439, 95% CI 1.075-5.525; P = .033) were independent prognostic factors for unfavorable OS. The COX analysis showed that related prognostic factors of worse RFS were TNM stage III (HR 3.802, 95% CI 1.506-9.615; P = .049) and LNR >0.25 (HR 2.326, 95% CI 1.332-4.065; P = .003).LNR can be used as an important prognostic indicator for gastric cancer patients with D2 resection and adjuvant chemoradiotherapy, and LNR more than 0.25 indicates poor prognosis.

Adjuvant chemoradiation for gastric carcinoma: State of the art and perspectives

An estimated 990,000 new cases of gastric cancer are diagnosed worldwide each year. Surgical excision, the only chance for prolonged survival, is feasible in about 20% of cases. Even after surgery, the median survival is limited to 12 to 20 months due to the frequency of locoregional and/or metastatic recurrences. This led to clinical trials associating surgery with neoadjuvant or adjuvant treatments to improve tumor control and patient survival. The most studied modalities are perioperative chemotherapy and adjuvant chemoradiotherapy. To date, evidence has shown a survival benefit for postoperative chemoradiotherapy and for perioperative chemotherapy. Phase III trials are ongoing to compare these two modalities. The aim of this review is to synthesize current knowledge about adjuvant chemoradiotherapy in the management of gastric adenocarcinoma, and to consider its prospects by integrating modern radiotherapy techniques.

A phase II trial of concurrent 3D-CRT/IMRT and oxaliplatin, 5-fluorouracil and leucovorin (FOLFOX) in gastric cancer patients with R0 gastrectomy and D2 lymph node dissection

BACKGROUND

To evaluate the safety and efficacy of a concurrent three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) plus oxaliplatin, 5-fluorouracil and leucovorin (FOLFOX) regimen in completely resected gastric cancer patients with D2 lymph node dissection.

MATERIALS AND METHODS

Patients with stage IB-IIIC gastric cancer (per the AJCC, 7th edition) who had undergone R0 and D2 gastrectomy were recruited. Two cycles of FOLFOX with concurrent 3D-CRT or IMRT (50.4 Gy/28f) were administered. One and an additional five cycles of FOLFOX were delivered before and after concurrent chemoradiotherapy, respectively. Primary endpoints were relapse-free survival (RFS) and overall survival (OS), with adverse events as secondary endpoints.

RESULTS

From 2008 to 2011, 110 patients were evaluable. The 1-, 2- and 3-year RFS and OS were 86.2, 72.2, 67.8 and 94.7, 87.2, 77.6%, respectively. On multivariate analysis, stage (≤ IIIA vs. >IIIA) was a statistically significant factor affecting both RFS and OS. Additionally, the T-category (≤ T4a vs. = T4b) was a statistically significant factor affecting only the RFS. The most commonly observed grade 3 or 4 adverse events were nausea and vomiting, decreased appetite, leukopenia/neutropenia and fatigue, each of which occurred in 14.5, 11.8, 9.1 and 6.4% patients, respectively.

CONCLUSIONS

Adjuvant 3D-CRT/IMRT to a dose of 50.4 Gy/28f with concurrent FOLFOX is safe and effective in patients following radical gastrectomy with D2 lymph node dissection.

Phase I study of postoperative radiotherapy concurrent with S-1 in patients with gastric cancer

Postoperative chemoradiotherapy (CRT) with concurrent 5-fluorouracil is the standard care for gastric cancer patients after curative surgery. The previous studies revealed that the subgroup of patients with high recurrence risk would benefit most from adjuvant CRT. S-1, a novel oral fluorouracil, has showed very effective in metastatic gastric cancer and became the standard option for gastric cancer with D2 dissection. The safety and dosage of S-1 combined with postoperative radiotherapy have not yet been evaluated. This study is to determine the maximum tolerate dose (MTD) and dose-limiting toxicity (DLT) of S-1 given concurrently with postoperative high-dose radiotherapy in gastric cancer. Patients with more advanced stage (pT4 and/or pN+) after R0 resection were recruited. Eligible patients received one cycle standard SOX (S-1 plus oxaliplatin) chemotherapy, then S-1 monotherapy with concurrent radiotherapy for 6 weeks, followed by additional three cycles of SOX. During the concurrent CRT, S-1 was administered on every radiotherapy treatment day according to a predefined dose-escalation schedule. Radiotherapy (3D-RT or IMRT) was given to a total dose of 50.4 Gy in 28 fractions. DLT was defined as grade 3 or 4 hematologic and non-hematologic toxicity. From March 2011 to October 2012, 21 patients were enrolled at five dose levels: 40 (n = 3), 50 (n = 3), 60 (n = 6), 70 (n = 6) and 80 mg/m(2)/day (n = 3). D2-dissection was performed in 18 patients (85.7 %) and 15 patients (71.4 %) had stage III disease. The most common dose-related toxicity was anorexia, nausea and vomiting, fatigue and leucopenia. DLT was occurred in one patient at 60 mg/m(2)/day (grade 3 fatigue), one patient at 70 mg/m(2)/day (grade 3 vomiting and anorexia), two patients at 80 mg/m(2)/day (one with grade 3 vomiting and anorexia; another with grade 3 febrile leucopenia). Four patients did not complete CRT as planned. Overall, this phase I study demonstrated that postoperative CRT with daily S-1 was feasible in gastric cancer and the MTD of S-1 concurrent with radiotherapy was 70 mg/m(2)/day. This S-1-based postoperative CRT will be investigated in a multicenter phase III study in West China.

Factors associated with early recurrence after curative surgery for gastric cancer

AIM: To characterize patterns of gastric cancer recurrence and patient survival and to identify predictors of early recurrence after surgery.

METHODS: Clinicopathological data for 417 consecutive patients who underwent curative resection for gastric cancer were retrospectively analyzed. Tumor and node status was reclassified according to the 7^th edition of the American Joint Committee on Cancer tumor-node-metastasis classification for carcinoma of the stomach. Survival data came from both the patients’ follow-up records and telephone follow-ups. Recurrent gastric cancer was diagnosed based on clinical imaging, gastroscopy with biopsy, and/or cytological examination of ascites, or intraoperative findings in patients who underwent reoperation. Predictors of early recurrence were compared in patients with pT1 and pT2-4a stage tumors. Pearson’s χ² test and Fisher’s exact test were used to compare differences between categorical variables. Survival curves were constructed using the Kaplan-Meier method and compared via the log-rank test. Variables identified as potentially important for early recurrence using univariate analysis were determined by multivariate logistic regression analysis.

RESULTS: Of 417 gastric cancer patients, 80 (19.2%) were diagnosed with early gastric cancer and the remaining 337 (80.8%) were diagnosed with locally advanced gastric cancer. After a median follow-up period of 56 mo, 194 patients (46.5%) experienced recurrence. The mean time from curative surgery to recurrence in these 194 patients was 24 ± 18 mo (range, 1-84 mo). Additionally, of these 194 patients, 129 (66.5%) experienced recurrence within 2 years after surgery. There was no significant difference in recurrence patterns between early and late recurrence (P < 0.05 each). For pT1 stage gastric cancer, tumor size (P = 0.011) and pN stage (P = 0.048) were associated with early recurrence of gastric tumors. Patient age, pT stage, pN stage, Lauren histotype, lymphovascular invasion, intraoperative chemotherapy, and postoperative chemotherapy were independent predictors of early recurrence in patients with pT2-4a stage gastric cancer (P < 0.05 each).

CONCLUSION: Age, pT stage, pN stage, Lauren histotype, lymphovascular invasion, intraoperative chemotherapy, and postoperative chemotherapy are independent factors influencing early recurrence of pT2-4a stage gastric cancer.

The synergistic effects of low dose fluorouracil and TRAIL on TRAIL-resistant human gastric adenocarcinoma AGS cells

The TNF-related apoptosis-inducing ligand (TRAIL) is a TNF family member which has been under intense focus because of its remarkable ability to induce apoptosis in malignant human cells while leaving normal cells unscathed. However, many cancer cells remain resistant to TRAIL. In this study, we had investigated the synergistic effects of low dose fluorouracil (5-Fu) and TRAIL on TRAIL-resistant human gastric adenocarcinoma AGS cells and explored the potential mechanisms. Cell viability was analyzed by sulforhodamine B (SRB) assay and the synergistic effects were evaluated by Jin's formula and confirmed by both morphological changes under inverted microscope and flow cytometry. The expression of TRAIL-R1 (death receptor 4, DR4), TRAIL-R2 (DR5), TRAIL-R3 (decoy receptor, DcR1), TRAIL-R4 (DcR2), procaspase-3, procaspase-8, and procaspase-9 was detected by western blotting. Our results showed that there were significant synergistic effects of low dose 5-Fu and TRAIL on TRAIL-resistant AGS cells, and this effect was supposed to be mediated by decreasing DcR2 expression and increasing DR5 expression. The extrinsic and intrinsic apoptosis pathways were both activated. The data suggest that combined treatment of low dose 5-Fu and TRAIL can be an effective therapeutic approach for gastric adenocarcinoma.

Single-arc volumetric-modulated arc therapy (sVMAT) as adjuvant treatment for gastric cancer: dosimetric comparisons with three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT)

To compare the dosimetric differences between the single-arc volumetric-modulated arc therapy (sVMAT), 3-dimensional conformal radiotherapy (3D-CRT), and intensity-modulated radiotherapy (IMRT) techniques in treatment planning for gastric cancer as adjuvant radiotherapy. Twelve patients were retrospectively analyzed. In each patient's case, the parameters were compared based on the dose-volume histogram (DVH) of the sVMAT, 3D-CRT, and IMRT plans, respectively. Three techniques showed similar target dose coverage. The maximum and mean doses of the target were significantly higher in the sVMAT plans than that in 3D-CRT plans and in the 3D-CRT/IMRT plans, respectively, but these differences were clinically acceptable. The IMRT and sVMAT plans successfully achieved better target dose conformity, reduced the V20/30, and mean dose of the left kidney, as well as the V20/30 of the liver, compared with the 3D-CRT plans. And the sVMAT technique reduced the V20 of the liver much significantly. Although the maximum dose of the spinal cord were much higher in the IMRT and sVMAT plans, respectively (mean 36.4 vs 39.5 and 40.6Gy), these data were still under the constraints. Not much difference was found in the analysis of the parameters of the right kidney, intestine, and heart. The IMRT and sVMAT plans achieved similar dose distribution to the target, but superior to the 3D-CRT plans, in adjuvant radiotherapy for gastric cancer. The sVMAT technique improved the dose sparings of the left kidney and liver, compared with the 3D-CRT technique, but showed few dosimetric advantages over the IMRT technique. Studies are warranted to evaluate the clinical benefits of the VMAT treatment for patients with gastric cancer after surgery in the future.