Dual Erb B Inhibition in Oesophago-gastric Cancer (DEBIOC): A phase I dose escalating safety study and randomised dose expansion of AZD8931 in combination with oxaliplatin and capecitabine chemotherapy in patients with oesophagogastric adenocarcinoma

Inhibition of AKT enhances chemotherapy efficacy and synergistically interacts with targeting of the Inhibitor of apoptosis proteins in oesophageal adenocarcinoma

The incidence of oesophageal adenocarcinoma (OAC) has risen six-fold in western countries over the last forty years but survival rates have only marginally improved. Hyperactivation of the PI3K-AKT-mTOR pathway is a common occurrence in OAC, driving cell survival, proliferation and resistance to chemotherapeutic agents. Inhibition of AKT has been explored as a treatment strategy with limited success and current inhibitors have failed to progress through clinical trials. Our study, describes a novel allosteric AKT inhibitor, ALM301, and demonstrates an enhancement of the efficacy of conventional chemotherapy when combined with ALM301 in OAC. Reduced sensitivity to ALM301 is associated with high expression of the Inhibitor of Apoptosis (IAP) family of proteins, particularly XIAP. Combined AKT and IAP inhibition synergistically enhanced OAC cell death and successfully re-sensitized ALM301 and chemotherapy resistant cell lines. A high degree of synergism was also observed in patient-derived OAC organoids indicating the potential clinical relevance of the combination. This study demonstrates the role for dual AKT/IAP inhibition in OAC and provides a strong rationale for the further investigation of this highly efficacious combination strategy.

Immune microenvironment modulation following neoadjuvant therapy for oesophageal adenocarcinoma: a translational analysis of the DEBIOC clinical trial

BACKGROUND

The Dual Erb B Inhibition in Oesophago-gastric Cancer (DEBIOC) trial reported an acceptable safety profile for neoadjuvant oxaliplatin and capecitabine (Xelox) ± AZD8931 in oesophageal adenocarcinoma (OAC) but limited efficacy. We evaluated the impact of neoadjuvant Xelox ± AZD8931, a novel small-molecule inhibitor with equipotent activity against epidermal growth factor receptor (EGFR), human epidermal growth factor receptor (HER)2 and HER3, on biological pathways using a unique software-driven solution.

PATIENTS AND METHODS

Transcriptomic profiles from 25 pre-treatment formalin-fixed paraffin-embedded OAC biopsies and 18 matched resection specimens, treated with Xelox + AZD8931 (n = 16) and Xelox alone (n = 9), were analysed using the Almac claraT total mRNA report analysing 92 gene signatures, 100 unique single-gene drug targets and 7337 single genes across 10 hallmarks of cancer. Gene-set enrichment analysis (GSEA) was utilised to investigate pathways governing pathological response. Tumour-infiltrating lymphocytes (TILs) were assessed digitally using the QuPath software.

RESULTS

Hierarchical clustering identified three molecular subgroups classified by activation of innate immune signalling. The immune-high subgroup was associated with HER2 positivity, increased pathological response and a marked reduction in immune signalling and TILs following neoadjuvant therapy. The immune-low cluster was predominantly HER2/EGFR-negative, and EGFR positivity was associated with the immune-mixed subgroup. Treatment with neoadjuvant therapy induced common resistance mechanisms, such as angiogenesis and epithelial-mesenchymal transition signalling, and a reduction in DNA repair signatures. Addition of AZD8931 was associated with reduction of expression of EGFR, HER2 and AKT pathways and also promoted an immunosuppressive microenvironment. GSEA showed that patients with a pathological response to treatment had increased immune signalling, whereas non-responders to neoadjuvant therapy were enriched for nucleotide repair and cellular growth through the action of E2F transcription factors.

CONCLUSION

OAC may be subdivided into three immune-related subgroups which undergo modulation in response to neoadjuvant therapy with marked suppression of the immune microenvironment in HER2-positive/immune-high tumours.

Pan-Cancer Analysis of GALNT6 with Potential Implications for Prognosis and Tumor Microenvironment in Human Cancer Based on Bioinformatics and qPCR Verification

Purpose

We explored the expression and prognostic value of GALNT6 and the tumor microenvironment of pan-cancer in humans.

Methods

In this study, we explored the expression pattern of GALNT6 pan-cancer across multiple databases. The prognostic value of GALNT6 was evaluated using the Kaplan-Meier method. The types and numbers of GALNT6 gene alterations were exhibited using the cBio Cancer Genomics Portal. The correlations between GALNT6 expression and immune infiltration in cancers were analyzed using the database Tumor Immune Estimation Resource 2. We also used the Kyoto Encyclopedia of Genes and Genomes pathway and Gene Ontology analysis to investigate the molecular mechanisms of the GALNT6 gene in tumorigenesis. The expression of GALNT6 was also further verified by qPCR in lung adenocarcinoma tissues.

Results

In general, compared with normal tissue, tumor tissue had a higher expression level of GALNT6. GALNT6 showed a protective effect in colon carcinoma and other cancers; however, a high expression level of GALNT6 was detrimental to survival in bladder cancer and in pheochromocytoma and paraganglioma. Mutation, amplification, and deep deletion were the three main types of GALNT6 mutations in tumors. There was a significant positive correlation between GALNT6 expression and immune infiltration of CD8+ T-cells in skin cutaneous melanoma metastasis, based on most of the algorithms used. Moreover, protein processing- and glycoprotein metabolic-associated functions were involved in the functional mechanisms of GALNT6.

Conclusion

This first pan-cancer study offers a relatively comprehensive understanding of the oncogenic roles of GALNT6 across different cancer types.

HER3-targeted therapy: the mechanism of drug resistance and the development of anticancer drugs

Human epidermal growth factor receptor 3 (HER3), which is part of the HER family, is aberrantly expressed in various human cancers. Since HER3 only has weak tyrosine kinase activity, when HER3 ligand neuregulin 1 (NRG1) or neuregulin 2 (NRG2) appears, activated HER3 contributes to cancer development and drug resistance by forming heterodimers with other receptors, mainly including epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2). Inhibition of HER3 and its downstream signaling, including PI3K/AKT, MEK/MAPK, JAK/STAT, and Src kinase, is believed to be necessary to conquer drug resistance and improve treatment efficiency. Until now, despite multiple anti-HER3 antibodies undergoing preclinical and clinical studies, none of the HER3-targeted therapies are licensed for utilization in clinical cancer treatment because of their safety and efficacy. Therefore, the development of HER3-targeted drugs possessing safety, tolerability, and sensitivity is crucial for clinical cancer treatment. This review summarizes the progress of the mechanism of HER3 in drug resistance, the HER3-targeted therapies that are conducted in preclinical and clinical trials, and some emerging molecules that could be used as future designed drugs for HER3, aiming to provide insights for future research and development of anticancer drugs targeting HER3.

Targeting HER2 in Gastroesophageal Adenocarcinoma: Molecular Features and Updates in Clinical Practice

Gastroesophageal adenocarcinoma (GEA) is one of the principal causes of death related to cancer globally. Human epidermal growth factor receptor 2 (HER2) is a tyrosine kinase receptor which is found to be overexpressed or amplified in approximately 20% of GEA cases. In GEA, the identification of HER2-positive status is crucial to activate a specific anti-HER2 targeted therapy. The landmark ToGA trial demonstrated the superiority of adding trastuzumab to platinum-based chemotherapy, becoming the first-line standard of treatment. However, unlike breast cancer, the efficacy of other anti-HER2 drugs, such as lapatinib, pertuzumab, and T-DM1, has failed to improve outcomes in advanced and locally advanced resectable GEA. Recently, the combination of trastuzumab with pembrolizumab, along with chemotherapy, and the development of trastuzumab deruxtecan, with its specific bystander activity, demonstrated improved outcomes, renewing attention in the treatment of this disease. This review will summarise historical and emerging therapies for the treatment of HER2-positive GEA, with a section dedicated to the HER2 molecular pathway and the use of novel blood biomarkers, such as circulating tumour DNA and circulating tumour cells, which may be helpful in the future to guide treatment decisions.

PANTHER: AZD8931, inhibitor of EGFR, ERBB2 and ERBB3 signalling, combined with FOLFIRI: a Phase I/II study to determine the importance of schedule and activity in colorectal cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) is a therapeutic target to which HER2/HER3 activation may contribute resistance. This Phase I/II study examined the toxicity and efficacy of high-dose pulsed AZD8931, an EGFR/HER2/HER3 inhibitor, combined with chemotherapy, in metastatic colorectal cancer (CRC).

METHODS

Treatment-naive patients received 4-day pulses of AZD8931 with irinotecan/5-FU (FOLFIRI) in a Phase I/II single-arm trial. Primary endpoint for Phase I was dose limiting toxicity (DLT); for Phase II best overall response. Samples were analysed for pharmacokinetics, EGFR dimers in circulating exosomes and Comet assay quantitating DNA damage.

RESULTS

Eighteen patients received FOLFIRI and AZD8931. At 160 mg bd, 1 patient experienced G3 DLT; 160 mg bd was used for cohort expansion. No grade 5 adverse events (AE) reported. Seven (39%) and 1 (6%) patients experienced grade 3 and grade 4 AEs, respectively. Of 12 patients receiving 160 mg bd, best overall response rate was 25%, median PFS and OS were 8.7 and 21.2 months, respectively. A reduction in circulating HER2/3 dimer in the two responding patients after 12 weeks treatment was observed.

CONCLUSIONS

The combination of pulsed high-dose AZD8931 with FOLFIRI has acceptable toxicity. Further studies of TKI sequencing may establish a role for pulsed use of such agents rather than continuous exposure.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov number: NCT01862003.

HER2-targeted advanced metastatic gastric/gastroesophageal junction adenocarcinoma: treatment landscape and future perspectives

Recently, the global incidence of gastric/gastroesophageal junction (G/GEJ) cancer has remained high. China is also a large country with a high gastric cancer (GC) incidence rate, where the cases of GC account for 40% of all cases worldwide. More than 90% of GEJ cancers are the adenocarcinoma pathological type. Patients with early-stage G/GEJ adenocarcinoma may have a better prognosis after surgery. In contrast, patients with advanced metastatic G/GEJ adenocarcinoma usually choose comprehensive treatment based on systemic pharmacotherapy, but the subsequent long-term survival is not optimistic. The discovery of various biomarkers, especially microsatellite instability (MSI), programmed cell death-ligand 1 (PD-L1), human epidermal growth factor receptor 2 (HER2), tumor mutational burden (TMB) and Epstein-Barr virus (EBV), has led to the identification of an increasing number of targeted populations and has greatly improved the clinical efficacy of treatments for G/GEJ adenocarcinoma. The ToGA trial added trastuzumab to standard chemotherapy, showed improved survival of patients with HER2-positive advanced G/GEJ adenocarcinoma and brought these patients into a new era of HER2-targeted therapy. Moreover, many HER2-targeted agents have been developed and studied in patients with advanced HER2-positive G/GEJ adenocarcinoma who have demonstrated excellent clinical outcomes. However, many patients experience disease progression with HER2-targeted therapy; hence, new anti-HER2 drugs keep being developed, significantly reducing HER2 resistance. This paper reviews HER2-targeted drugs for advanced metastatic G/GEJ adenocarcinoma, potential resistance mechanisms and future directions.

A systematic review of HER2 blockade for the curative treatment of gastroesophageal adenocarcinoma: Successes achieved and opportunities ahead

INTRODUCTION

Despite multimodality treatment for curatively-treated gastroesophageal adenocarcinoma (GEA), prognosis remains dismal. The benefit of adding trastuzumab to chemotherapy for advanced Human Epidermal Growth Factor 2 (HER2) positive GEA has been established in the ToGA trial. However, it remains unclear if HER2 inhibition might also be beneficial in the curative setting. Therefore, we conducted a systematic review to investigate the role of HER2 inhibitors for the curative treatment of GEA.

METHODS

A systematic literature search was performed in PubMed, EMBASE, CENTRAL, and clinicaltrials.gov to identify clinical trials investigating HER2 inhibition for the curative treatment of GEA. Study quality was assessed using the GRADE methodology.

RESULTS

From the 1825 studies retrieved, 17 were included (seven published articles; three published conference abstracts; seven ongoing studies). From the published studies, eight studies investigated single-agent HER2 inhibition. Four studies had a nonrandomized design, and two were randomized controlled trials. Two published studies were assessed as high-quality. The addition of single-agent HER2 inhibition to chemo(radio)therapy showed a pathological complete response rate (pCR) of 22.2% (range, 9.6-25%) and dual HER2 inhibition of 34.5% (34-35%). Two-year disease-free survival (DFS) was 51.0% (40-71%) with single-agent and 70.0% (70-70%) with dual HER2 therapy.

DISCUSSION

Dual-agent HER2 inhibition showed promising pCR rates and DFS. Given the limited additional toxicity of the addition of HER2 targeting agents and the potential benefit of dual-targeting, further investigation is required in a phase III randomized clinical trial. Next steps include combining checkpoint inhibitors and HER2 blockade given the suggested synergism, as well as investigating new anti-HER2 agents.

Gastric Cancer Harboring an ERBB3 Mutation Treated with a Pyrotinib-Irinotecan Combo: A Case Study

Gastric cancer is common, especially in East Asian countries, and is associated with high recurrence and mortality rates. Currently, there is no standard third-line treatment for metastatic gastric cancer. In this report, we present the case of a 69-year-old man with advanced gastric cancer, whose tumor was negative for human epidermal growth factor receptor 2 (HER2) according to immunohistochemical analysis. Next-generation sequencing performed on paraffin sections of the postoperative tumor samples indicated the presence of the ERBB3 V104L mutation. The patient received irinotecan plus pyrotinib as a third-line therapy and achieved a progression-free survival of 7.6 months with a high quality of life. Therefore, the combined administration of irinotecan and pyrotinib may improve the clinical condition of patients with gastric cancer harboring an ERBB3 mutation. Moreover, ERBB3 could be a potential therapeutic target for gastric cancer.

Development and Challenges of the Discovery of HER2 Inhibitors

The treatment of cancer has always been a major problem in the world. Some cancers cannot be treated with surgery, but only with cancer drugs. Among many cancer drugs, small molecule inhibitors play an irreplaceable role. HER2 is one of the HER families, and the development of HER2 inhibitors has made a huge contribution to the treatment of cancer. Some HER2 inhibitors are already on the market, and some HER2 inhibitors are undergoing clinical research. The design, synthesis and development of new HER2 inhibitors targeting different targets are also ongoing, and some are even under clinical research. The HER2 inhibitors that are on the market have developed resistance, which brings great challenges to the HER2 inhibitor development in the future. This article reviews the development and challenges of the discovery of HER2 inhibitors.