The role of different adjuvant therapies in locally advanced gastric adenocarcinoma

Survival and Recurrence Patterns in Patients With Stomach Adenocarcinoma Receiving Chemotherapy or Chemoradiotherapy After D2 Gastrectomy in a Tertiary Care Cancer Institute: A Retrospective Real-World Evidence Cohort Study

Purpose

Clinical trials comparing the efficacy of adjuvant chemotherapy (CT) and chemo radiation therapy (CTRT) for stomach adenocarcinoma have reported equivocal results. Hence, the current retrospective cohort study assessed the long-term survival and recurrence outcomes of these therapies, to generate evidence in a real-world scenario.

Methods and Materials

Pathologically confirmed patients with stomach adenocarcinoma aged ≥18 years who underwent gastrectomy and D2 lymph nodal dissection at a tertiary cancer hospital from January 2010 to October 2017 were enrolled. Hospital-based follow-up was performed until December 2021. Data were gathered from electronic medical records, supplemented by telephonic interviews for patients who could not come for physical follow-up. CT-alone and CTRT cohorts were compared in terms of survival and recurrence outcomes.

Results

The analysis included 158 patients (mean age, 56.42 years; 63.9% male; CT-alone cohort, 69; CTRT cohort, 89). Patients in the CTRT cohort had significantly worse tumor characteristics at baseline (29.2% had the diffuse type of tumor, 94.4% had stage II or III, 68.5% had lympho-vascular space invasion, and 85.4% had lymph node involvement). Recurrence was observed in 13 (19.7%) of the 76 followed-up patients. Although locoregional recurrence was higher in the CT-alone cohort (7 vs 2), distant metastasis was higher in the CTRT cohort (3 vs 1). The overall 5-year survival was 67.0% (SE, 5.0%) and 5-year recurrence-free survival (RFS) was 75.0% (SE, 5.0%). On multivariate Cox regression, no variable was significantly associated with the overall survival, whereas age, positive lymph nodes without extracapsular extension, and lymph node-negative were significantly associated with RFS. The CTRT cohort had significantly (84.0%) higher RFS (hazard ratio, 0.161; 95% CI, 0.056-0.464; P < .001).

Conclusions

Patients who received adjuvant CTRT after D2 dissection showed similar overall survival but significantly higher RFS than the CT-alone cohort, despite having worse baseline tumor characteristics.

Combination therapy of Doxorubicin with TTFields and radiation: newer approaches to combat lung cancer

BACKGROUND

Tumor-treating fields (TTFields) have been used singly or with chemoradiation for treating glioblastoma and mesothelioma but not yet for lung cancer. Survival rates in lung cancer remain abysmal despite advances in early diagnosis and targeted therapies.

AIMS AND OBJECTIVES

We aimed to investigate the effectiveness of TTFields in inhibiting lung cancer growth and metastasis, as well as the therapeutic effectiveness of TTFields alongside radiation and chemosensitivity-enhancing agents in an in vitro model.

METHODS

We generated TTFields yielding 0-800 V sine-wave signals, 0.9 V/cm applied electric field intensity, and 150 kHz frequency. The human lung cancer cell lines A549 and H460 were used in this study. Cell viability, colony formation, cell death detection, and cell invasion assays were performed to assess the therapeutic effectiveness of TTFields; sensitization of lung cancer cells to TTFields by doxorubicin (DOX); and the combined effect of TTFields, DOX, and irradiation (IR).

RESULTS

Lung cancer cells showed a nearly 20% decrease in cell viability at 1 V/cm and 150 kHz. In A549 and H460 cells, TTFields increased apoptosis through increased cleaved caspase3, hindered cell migration and invasion, and improved chemosensitivity to DOX. The combination of DOX and TTFields showed better antitumor results than those of each individually. However, the DOX/TTFields/IR combination was most effective in reducing the viability and migration of lung cancer cells.

CONCLUSION

TTFields as an adjuvant therapy offers probability for improving lung cancer patient outcomes.

Primary tumor resection benefited the survival of patients with distant metastatic gastric cancer

Background:

The role of surgery in the treatment of patients with distant metastatic (M1) gastric cancer (GC) remains controversial currently. This study aimed to clarify the impact of primary tumor resection (PTR) on the survival of such patients.

Materials and Methods:

The surveillance, epidemiology, and end results database was adopted to extract eligible patients. We designed a retrospective case–control study. The patients were divided into two groups according to whether they received PTR. The 1:1 propensity score matching (PSM) analysis was performed to balance the confounding factors between no-surgery and surgery groups. The categorical variables were described with Chi-square tests. Cancer-specific survival (CSS) and overall survival (OS) were evaluated by Kaplan–Meier method with log-rank test. Cox proportional hazard models were utilized to identify prognostic factors of CSS.

Results:

A total of 1716 patients were included, including 1108 (64.6%) patients without surgery and 608 (35.4%) patients with surgery. After PSM, most confounders were well balanced between the two comparison groups. Survival analysis in matched cohorts indicated that surgery exerted significant survival advantages in both CSS and OS curves. The median CSS was 11.0 (9.8–12.2) months in the surgery group versus 9.0 (8.0–10.0) months in the no-surgery group (P < 0.001). Multivariable Cox regression analysis identified surgery as an independent prognostic factor for favorable prognosis (hazard ratio: 0.689, 95% confidence interval: 0.538–0.881, P = 0.003).

Conclusion:

Surgery showed significant survival benefits for the patients with M1 stage GC. Our study has provided additional evidence to support PTR for these patients.

Minimal residual disease in advanced or metastatic solid cancers: The G0-G1 state and immunotherapy are key to unwinding cancer complexity

In the last decade, a large amount of research has focused on elucidating the mechanisms that account for homing disseminated cancer cells (DCCs) from solid tumours to distant organs, which successively progress to overt metastatic disease; this is currently incurable. A better understanding of DCC behaviour is expected to allow detectable metastasis prevention by more effectively targeting 'metastatic seeds before they sprout'. As DCC biology co-evolved with that of the primary tumour, and due to the many similarities between them, the term 'niche' has been borrowed from normal adult stem cells (ASCs) to define the site of DCC metastatic colonisation. Moreover, heterogeneity, survival, protection, stemness and plasticity as well as the prolonged G0-G1 dormant state in the metastatic niche have been the main aspects of intense investigation. Consistent with these findings, in solid cancers with minimal residual disease (MRD), it has been proposed to prolong adjuvant therapy by targeting specific molecular pathway(s) involving DCC dormancy. However, so far, few disappointing clinical data have been reported. As an alternative strategy, because immune-surveillance contributes to the steady state of the DCC population and likely to the G0-G1 state of cancer cells, we have used prolonged immune-modulatory cytostatic chemotherapy, active immune stimulation with an INF-β/IL-2 sequence or drugs inhibiting myeloid-derived suppressor cell (MDSC)/Treg-mediated immune suppression. This strategy, mainly aimed at boosting the immune response, is based on recent findings suggesting the downregulation of immune escape mechanisms as well as other principal hallmarks during the G0-G1 state and/or in MRD. Preliminary clinical and/or laboratory data suggest the efficacy of this strategy in gastrointestinal and some endocrine-dependent cancers. Following this, we propose therapeutic schedules to prevent DCC activation and proliferation in solid cancers at a high risk of relapse or as maintenance therapy in metastatic patients after complete response (CR) to conventional treatment.

Gramicidin inhibits human gastric cancer cell proliferation, cell cycle and induced apoptosis

Background

Gastric cancer is a common malignant tumor with high morbidity and mortality worldwide, which seriously affects human health. Gramicidin is a short peptide antibiotic which could be used for treating infection induced by bacteria or fungi. However, the anti-cancer effect of gramicidin on gastric cancer cells and its underlying mechanism remains largely unknown.

Results

Gastric cancer cells SGC-7901, BGC-823 and normal gastric mucosal cells GES-1 were treated with different concentrations of gramicidin respectively. The results of CCK-8 experiment revealed cellular toxicity of gramicidin to cancer cells while cell colony formation assay showed that gramicidin significantly inhibited the proliferation of gastric cancer cells, but had little effect on normal gastric mucosal cells. In addition, the wound healing assay showed that gramicidin inhibited the migration of SGC-7901 cell. Meanwhile, apoptosis and cell cycle analysis revealed that gramicidin induced cell apoptosis with G2/M cell cycle inhibition. Furthermore, western blot analysis demonstrated that gramicidin down-regulated the expression of cyclinD1 and Bcl-2 as well as the FoxO1 phosphorylation.

Conclusions

The current study illustrated the anti-tumor activity of gramicidin on gastric cancer cells, providing a possibility for gramicidin to be applied in clinical practice for the treatment of gastric cancer.

Downregulated Circular RNA hsa_circ_0000291 Suppresses Migration And Proliferation Of Gastric Cancer Via Targeting The miR-183/ITGB1 Axis

Background

Circular RNAs are implicated in a variety of cancers. This investigation found that hsa_circ_0000291 expression was upregulated in gastric cancer (GC) cell lines, yet its role in GC has not yet been reported.

Objective

To explore the effects of hsa_circ_0000291 on GC cell proliferation and invasion.

Materials and methods

In the current research, we used the gastric cancer cell lines MGC803 and MKN-28 to study hsa_circ_0000291 function. The relationship between hsa_circ_0000291, miR-183 and ITGB1 was analyzed by firefly luciferase analysis and Western blots, and qRT-PCR approaches were used for protein and gene expression analysis, respectively. Tumor growth and metastasis were determined in nude mice xenografts using MKN-28 cells, with or without hsa_circ_000r0291 downregulation.

Results

Our data showed that hsa_circ_0000291 was upregulated in GC cell lines, whereas hsa_circ_0000291 silencing suppressed cell metastasis and proliferation in in vivo and in vitro studies. Our results showed that the downregulation of hsa_circ_0000291 suppressed integrin beta 1 (ITGB1) expression via miR-183 “sponging,” which was validated by rescue experiments using the luciferase reporter assay. Our observations suggested that hsa_circ_0000291 silencing suppressed the aggressive, metastatic GC phenotype.

Conclusion

Taken together, hsa_circ_0000291 knockdown inhibited GC cell metastasis and growth by regulating the miR-183/ITGB1 axis. Importantly, this approach could provide a therapy target and potential biomarker for the diagnosis and treatment of GC.