Targeted Therapies and Developing Precision Medicine in Gastric Cancer

Dual Targeting of MEK1 and Akt Kinase Identified SBL-027 as a Promising Lead Candidate to Control Cell Proliferations in Gastric Cancer

Dual inhibition of Akt and MEK1 pathways offers a promising strategy to enhance treatment efficacy in gastric cancer. In this study, we employed computational approaches followed by in vitro validations. Our results demonstrate that SBL-027 exhibits robust and enduring interactions with Akt and MEK1 kinases, as evidenced by atomistic molecular dynamics simulations and molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) based binding free energy estimates. The predicted Gibbs binding free energies indicate highly favorable interactions between SBL-027 and both Akt and MEK1 kinases. In vitro, SBL-027 displayed an IC50 value of 195.20 nM against Akt and 239.10 nM against MEK1 enzymes. The compound exhibited potent inhibition of cell proliferation in KATOIII and SNU-5 cells, with GI50 values of 490.70 and 615.14 nM, respectively. Moreover, SBL-027 induced an increase in the sub G0/G1 population during the cell cycle of KATOIII and SNU-5 cells, while facilitating early and late-phase apoptosis in these cell lines. Notably, the compound significantly reduced the percentage of dual-positive cells expressing both MEK1 and Akt in gastric cancer cells. The strong binding affinity, stability, and favorable thermodynamics of SBL-027 along with the established in vitro efficacy highlight its potential as a lead compound for further preclinical and clinical development.

Deep learning-based prediction of HER2 status and trastuzumab treatment efficacy of gastric adenocarcinoma based on morphological features

BACKGROUND

First-line treatment for advanced gastric adenocarcinoma (GAC) with human epidermal growth factor receptor 2 (HER2) is trastuzumab combined with chemotherapy. In clinical practice, HER2 positivity is identified through immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH), whereas deep learning (DL) can predict HER2 status based on tumor histopathological features. However, it remains uncertain whether these deep learning-derived features can predict the efficacy of anti-HER2 therapy.

METHODS

We analyzed a cohort of 300 consecutive surgical specimens and 101 biopsy specimens, all undergoing HER2 testing, along with 41 biopsy specimens receiving trastuzumab-based therapy for HER2-positive GAC.

RESULTS

We developed a convolutional neural network (CNN) model using surgical specimens that achieved an area under the curve (AUC) value of 0.847 in predicting HER2 amplification, and achieved an AUC of 0.903 in predicting HER2 status specifically in patients with HER2 2 + expression. The model also predicted HER2 status in gastric biopsy specimens, achieving an AUC of 0.723. Furthermore, our classifier was trained using 41 HER2-positive gastric biopsy specimens that had undergone trastuzumab treatment, our model demonstrated an AUC of 0.833 for the (CR + PR) / (SD + PD) subgroup.

CONCLUSION

This work explores an algorithm that utilizes hematoxylin and eosin (H&E) staining to accurately predict HER2 status and assess the response to trastuzumab in GAC, potentially facilitating clinical decision-making.

Efficacy and safety of ramucirumab in gastric or gastroesophageal cancer: A systematic review and meta-analysis

BACKGROUND

Ramucirumab is considered a potential treatment for gastric or gastroesophageal cancer; however, its safety has not been evaluated. This meta-analysis aimed to evaluate the efficacy and safety of ramucirumab for treating gastric or gastroesophageal cancer.

METHODS

The databases of PubMed, Embase, and Cochrane Library were searched through October 2023. The search focused on randomized controlled trials (RCTs) comparing ramucirumab (with or without chemotherapy) to a placebo (with or without chemotherapy) in patients with gastric or gastroesophageal cancer. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and adverse events (AEs) were pooled.

RESULTS

Seven RCTs with a total of 2613 patients were included. Compared with placebo (with or without chemotherapy), ramucirumab (with or without chemotherapy) significantly improved OS (HR: 0.90, 95% CI: 0.82-0.99, p = 0.030), PFS (HR: 0.74, 95% CI: 0.60-0.90, p = 0.003), ORR (OR: 1.39, 95% CI: 1.15-1.67, p < 0.001), and DCR (OR: 1.91, 95% CI: 1.38-2.63, p < 0.001). However, ramucirumab (with or without chemotherapy) also increased the incidence of decreased appetite (OR: 1.29, 95% CI: 1.09-1.53, p = 0.004), diarrhea (OR: 1.39, 95% CI: 1.01-1.91, p = 0.05), hypertension (OR: 3.13, 95% CI: 2.03-4.83, p < 0.00001), and bleeding or hemorrhage (OR: 2.34, 95% CI: 1.93-2.85, p < 0.00001).

CONCLUSIONS

Ramucirumab (with or without chemotherapy) can improve OS, PFS, ORR and DCR in patients with gastric or gastroesophageal cancer. However, it may also increase the incidence of specific AEs.

SMYD5 methylation of rpL40 links ribosomal output to gastric cancer

Dysregulated transcription due to disruption in histone lysine methylation dynamics is an established contributor to tumorigenesis1,2. However, whether analogous pathologic epigenetic mechanisms act directly on the ribosome to advance oncogenesis is unclear. Here we find that trimethylation of the core ribosomal protein L40 (rpL40) at lysine 22 (rpL40K22me3) by the lysine methyltransferase SMYD5 regulates mRNA translation output to promote malignant progression of gastric adenocarcinoma (GAC) with lethal peritoneal ascites. A biochemical-proteomics strategy identifies the monoubiquitin fusion protein partner rpL40 (ref. 3) as the principal physiological substrate of SMYD5 across diverse samples. Inhibiting the SMYD5-rpL40K22me3 axis in GAC cell lines reprogrammes protein synthesis to attenuate oncogenic gene expression signatures. SMYD5 and rpL40K22me3 are upregulated in samples from patients with GAC and negatively correlate with clinical outcomes. SMYD5 ablation in vivo in familial and sporadic mouse models of malignant GAC blocks metastatic disease, including peritoneal carcinomatosis. Suppressing SMYD5 methylation of rpL40 inhibits human cancer cell and patient-derived GAC xenograft growth and renders them hypersensitive to inhibitors of PI3K and mTOR. Finally, combining SMYD5 depletion with PI3K-mTOR inhibition and chimeric antigen receptor T cell administration cures an otherwise lethal in vivo mouse model of aggressive GAC-derived peritoneal carcinomatosis. Together, our work uncovers a ribosome-based epigenetic mechanism that facilitates the evolution of malignant GAC and proposes SMYD5 targeting as part of a potential combination therapy to treat this cancer.

Pembrolizumab in combination with trastuzumab for treatment of HER2-positive advanced gastric or gastro-esophageal junction cancer

Introduction

Gastric cancer remains a challenging malignancy with a high global mortality rate. Recent advances in targeted therapy and immunotherapy have shown promise in improving patient outcomes. This paper reviews the impact of incorporating targeted agents such as trastuzumab and immunotherapeutic agents like pembrolizumab into standard chemotherapy regimens for gastric cancer treatment.

Methods

A comprehensive analysis was conducted on pivotal clinical trials, including KEYNOTE-590, KEYNOTE-811, and ToGA, focusing on their methodologies, patient populations, treatment regimens, and outcome measures. The review also explored emerging research avenues in precision medicine, particularly genomic sequencing and biomarker identification.

Aim

To assess the efficacy and survival benefits of adding trastuzumab and pembrolizumab to standard chemotherapy in the treatment of gastric cancer and to outline future directions in gastric cancer research.

Results

Including trastuzumab and pembrolizumab in treatment regimens for human epidermal growth factor receptor 2 (HER2)-positive and PD-L1-expressing gastric cancers significantly improved progression-free and overall survival rates compared to chemotherapy alone. These findings highlight the potential of personalized therapy in enhancing treatment outcomes. Furthermore, ongoing research into the gastric cancer microenvironment and the role of the microbiome suggests novel targets for future therapeutic interventions.

Conclusion

The integration of targeted and immunotherapeutic agents with traditional chemotherapy represents a pivotal shift in gastric cancer treatment, moving towards more personalized and effective regimens.

State-of-the-Art Advancements in Gastroesophageal Cancer Treatment: Harnessing Biomarkers for Precision Care

Gastroesophageal cancers (GECs) represent a significant clinical challenge. For early resectable GEC, the integration of immune checkpoint inhibitors into the perioperative chemotherapy and chemoradiation treatment paradigms are being explored and showing promising results. Frontline management of metastatic GEC is exploring the role of targeted therapies beyond PD-1 inhibitors, including anti-human epidermal growth factor receptor 2 agents, Claudin 18.2 inhibitors, and FGFR2 inhibitors, which have shown considerable efficacy in recent trials. Looking ahead, ongoing trials and emerging technologies such as bispecific antibodies, antibody-drug conjugates, and adoptive cell therapies like chimeric antigen receptor T cells are expected to define the future of GEC management. These advancements signify a paradigm shift toward personalized and immunotherapy-based approaches, offering the potential for improved outcomes and reduced toxicity for patients with GEC.

Immunotherapy and targeted therapy as first-line treatment for advanced gastric cancer

For patients diagnosed with advanced gastric or gastroesophageal cancer that is not amenable to surgical intervention, the standard of care for first-line treatment consists of fluoropyrimidine and platinum-based chemotherapy. The incorporation of novel agents into these standard first-line regimens could potentially improve patient prognosis; options for such augmentations include both immune-based and targeted therapy combinations. To provide a comparative analysis of these different first-line combination treatments, a network meta-analysis was conducted. Outcome measures comprised overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and grade 3-4 treatment-related adverse events (TRAEs). Data were drawn from 22 randomized controlled trials, encompassing 10,787 patients and 17 distinct treatment regimens. Our findings suggest that FGFR2b-targeted therapy, specifically when used in combination with chemotherapy (bemarituzumab_chemo), exhibited the greatest efficacy. This was followed by immunotherapy-based combination regimens (CPS ≥5, Sintilimab_chemo). Further, targeted combination therapy featuring CLAUDIN 18.2 (zolbetuximab_chemo) appeared beneficial based on individual patient characteristics. In the case of HER2-positive patients, the trastuzumab_chemo regimen is recommended, as most existing studies have excluded this subpopulation. These results have significant implications for both clinical decision-making and patient care in the realm of advanced gastric or gastroesophageal cancer treatment.

Exploring the immune escape mechanisms in gastric cancer patients based on the deep AI algorithms and single-cell sequencing analysis

Gastric cancer is a prevalent and deadly malignancy, and the response to immunotherapy varies among patients. This study aimed to develop a prognostic model for gastric cancer patients and investigate immune escape mechanisms using deep machine learning and single-cell sequencing analysis. Data from public databases were analysed, and a prediction model was constructed using 101 algorithms. The high-AIDPS group, characterized by increased AIDPS expression, exhibited worse survival, genomic variations and immune cell infiltration. These patients also showed immunotherapy tolerance. Treatment strategies targeting the high-AIDPS group identified three potential drugs. Additionally, distinct cluster groups and upregulated AIDPS-associated genes were observed in gastric adenocarcinoma cell lines. Inhibition of GHRL expression suppressed cancer cell activity, inhibited M2 polarization in macrophages and reduced invasiveness. Overall, AIDPS plays a critical role in gastric cancer prognosis, genomic variations, immune cell infiltration and immunotherapy response, and targeting GHRL expression holds promise for personalized treatment. These findings contribute to improved clinical management in gastric cancer.

Immunotherapy in Esophagogastric Cancer: Treatment Landscape, Challenges, and New Directions

BACKGROUND

Cancers of the upper gastrointestinal tract represent a lethal disease entity comprising the esophagus, gastroesophageal junction, and stomach. The backbone of therapy in esophagogastric cancers has predominantly been chemotherapy-based. However, over the last decade, with the debut of immune checkpoint inhibitors, sophisticated molecular testing, and a more comprehensive understanding of the tumor microenvironment, immunotherapy has been incorporated into the treatment of localized and advanced esophagogastric cancers with promising results.

PURPOSE

This study aimed to review the unique tumor microenvironment and role of immunotherapy in esophagogastric cancers.

METHODS

We conducted a systematic review of clinical and translational research for immunotherapy in esophagogastric cancers.

RESULTS

This article will explore the unique tumor microenvironment in gastroesophageal cancers, the role of immunotherapy in localized and advanced disease, challenges in management, and new therapeutic approaches in clinical trials.

CONCLUSION

With further exploration into targeted therapy and immunotherapy, we anticipate the emergence of novel treatments that will improve survival and quality of life in patients with esophagogastric cancers.

Role of circular RNAs and gut microbiome in gastrointestinal cancers and therapeutic targets

Gastrointestinal cancers are a huge worldwide health concern, which includes a wide variety of digestive tract cancers. Circular RNAs (circRNAs), a kind of non-coding RNA (ncRNAs), are a family of single-stranded, covalently closed RNAs that have become recognized as crucial gene expression regulators, having an impact on several cellular functions in cancer biology. The gut microbiome, which consists of several different bacteria, actively contributes to the regulation of host immunity, inflammation, and metabolism. CircRNAs and the gut microbiome interact significantly to greatly affect the growth of GI cancer. Several studies focus on the complex functions of circRNAs and the gut microbiota in GI cancers, including esophageal cancer, colorectal cancer, gastric cancer, hepatocellular cancer, and pancreatic cancer. It also emphasizes how changed circRNA expression profiles and gut microbiota affect pathways connected to malignancy as well as how circRNAs affect hallmarks of gastrointestinal cancers. Furthermore, circRNAs and gut microbiota have been recommended as biological markers for therapeutic targets as well as diagnostic and prognostic purposes. Targeting circRNAs and the gut microbiota for the treatment of gastrointestinal cancers is also being continued to study. Despite significant initiatives, the connection between circRNAs and the gut microbiota and the emergence of gastrointestinal cancers remains poorly understood. In this study, we will go over the most recent studies to emphasize the key roles of circRNAs and gut microbiota in gastrointestinal cancer progression and therapeutic options. In order to create effective therapies and plan for the future gastrointestinal therapy, it is important to comprehend the functions and mechanisms of circRNAs and the gut microbiota.

Targeting FGFR Pathways in Gastrointestinal Cancers: New Frontiers of Treatment

In carcinogenesis of the gastrointestinal (GI) tract, the deregulation of fibroblast growth factor receptor (FGFR) signaling plays a critical role. The aberrant activity of this pathway is described in approximately 10% of gastric cancers and its frequency increases in intrahepatic cholangiocarcinomas (iCCAs), with an estimated frequency of 10-16%. Several selective FGFR inhibitors have been developed in the last few years with promising results. For example, targeting the FGFR pathway is now a fundamental part of clinical practice when treating iCCA and many clinical trials are ongoing to test the safety and efficacy of anti-FGFR agents in gastric, colon and pancreatic cancer, with variable results. However, the response rates of anti-FGFR drugs are modest and resistances emerge rapidly, limiting their efficacy and causing disease progression. In this review, we aim to explore the landscape of anti-FGFR inhibitors in relation to GI cancer, with particular focus on selective FGFR inhibitors and drug combinations that may lead to overcoming resistance mechanisms and drug-induced toxicities.