Https://doi.org/10.18632/oncotarget.27659 Lisi Elizabeth Lim, David L. Chan, David Thomas, Yang Du, Gary Tincknell, Anna Kuchel, Alexander Davis, Dale L. Bailey, Nick Pavlakis, Gabrielle Cehic,...

Gastric and oesophageal cancers (GOCs) are lethal cancers which metastasise early and recur frequently, even after definitive surgery. The urokinase plasminogen activator system (uPAS) is strongly implicated in the invasion and metastasis of many aggressive tumours including GOCs. Urokinase plasminogen activator (uPA) interaction with its receptor, urokinase plasminogen activator receptor (uPAR), leads to proteolytic activation of plasminogen to plasmin, a broad-spectrum protease which enables tumour cell invasion and dissemination to distant sites. uPA, uPAR and the plasminogen activator inhibitor type 1 (PAI-1) are overexpressed in some GOCs. Accumulating evidence points to a causal role of activated receptor tyrosine kinase pathways enhancing uPAS expression in GOCs. Expression of these components are associated with poorer clinicopathological features and patient survival. Stromal cells, including tumour-associated macrophages and myofibroblasts, also express the key uPAS proteins, supporting the argument of stromal involvement in GOC progression and adverse effect on patient survival. uPAS proteins can be detected on circulating leucocytes, circulating tumour cells and within the serum; all have the potential to be developed into circulating biomarkers of GOC. Herein, we review the experimental and clinical evidence supporting uPAS expression as clinical biomarker in GOC, with the goal of developing targeted therapeutics against the uPAS.

Brain metastasis from gastroesophageal adenocarcinomas (GOCs) is a rare but a devastating diagnosis. Human epidermal growth factor receptor 2 (HER2) is a prognostic and predictive biomarker in GOCs. The association of HER2 with GOC brain metastasis is not known. We performed a retrospective analysis of patients with GOCs with known HER2 status between January 2015 and November 2021. HER2 was assessed on either the primary tumour or metastasis by immunohistochemistry or in situ hybridization. The diagnosis of brain metastasis was made on standard imaging techniques in patients with symptoms or signs. HER2 results were available for 201 patients, with 34 patients (16.9%) HER2 positive. A total of 12 patients developed symptomatic brain metastasis from GOCs, of which 7 (58.3%) were HER2 positive. The development of symptomatic brain metastasis was significantly higher in the HER2-positive GOCs (OR8.26, 95%CI 2.09–35.60; p = 0.0009). There was no significant association of HER2 status and overall survival in patients with brain metastasis. Although the rate of brain metastasis remains low in GOCs, the incidence of symptomatic brain metastasis was significantly higher in patients with HER2-positive tumours.

The prognosis for metastatic gastric adenocarcinoma (mGAC) remains poor. Gene alterations in receptor tyrosine kinases (RTKs) such as epidermal growth factor receptor (EGFR) and their downstream effectors including catalytic subunit alpha of the phosphatidylinositol 3-kinase (PIK3CA) are common in mGAC. Targeted RTK and phosphatidylinositol-3-kinase (PI3K) treatments have demonstrated clinical benefits in other solid tumours and are key potential targets for clinical development against mGAC given the presence of recurrent alterations in these pathways. Furthermore, combination RTK/PI3K treatments may overcome compensatory mechanisms that arise using monotherapies, leading to improved patient outcomes. Herein, we investigated RTK/PI3K single and combination drug responses against our unique human mGAC-derived PIK3CA gain-of-function mutant, human epidermal growth factor receptor 2 (HER2)-negative, EGFR-expressing circulating tumour cell line, UWG02CTC, under two- and three-dimensional culture conditions to model different stages of metastasis. UWG02CTCs were highly responsive to the PI3K p110α-subunit targeted drugs PIK-75 (IC₅₀ = 37.0 ± 11.1 nM) or alpelisib (7.05 ± 3.7 µM). Drug sensitivities were significantly increased in 3D conditions. Compensatory MAPK/ERK pathway upregulation by PI3K/Akt suppression was overcome by combination treatment with the EGFR inhibitor gefitinib, which was strongly synergistic. PIK-75 plus gefitinib significantly impaired UWG02CTC invasion in an organotypic assay. In conclusion, UWG02CTCs are a powerful ex vivo mGAC drug responsiveness model revealing EGFR/PI3K-targeted drugs as a promising combination treatment option for HER2-negative, RAS wild-type mGAC patients.

The treatment of early-stage non-small cell lung cancer (NSCLC) is becoming increasingly complex. Standard of care management for the past decade has been adjuvant chemotherapy following curative intent resection regardless of nodal status or tumour profile. With the increased incorporation of immunotherapy in NSCLC, especially in the locally advanced, unresectable, or metastatic settings, multiple studies have sought to assess its utility in early-stage disease. While there are suboptimal responses to neoadjuvant chemotherapy alone, there is a strong rationale for the use of neoadjuvant immunotherapy in tumour downstaging, based upon the concept of enhanced T cell priming at the time of a high tumour antigen burden, and demonstrated clinically in other solid tumours, such as melanoma. In the NSCLC cancer setting, currently over 20 combinations of chemoimmunotherapy in the neoadjuvant and perioperative setting have been studied with results variable. Multiple large phase III studies have demonstrated that neoadjuvant chemoimmunotherapy combinations result in significant advances in pathological response, disease free and overall survival which has led to practice change across the world. Currently, combination immunotherapy regimens with novel agents targeting alternate immunomodulatory pathways are now being investigated. Given this, the landscape of treatment in resectable early-stage NSCLC has become increasingly complex. This review outlines the literature of neoadjuvant and perioperative immunotherapy and discusses its potential benefits and complexities and ongoing considerations into future research.

In patients with gastric, gastroesophageal junction or esophageal adenocarcinoma (GOC), peri-operative multimodal therapies have improved survival; however, prognosis remains underwhelming. Pre-operative nutritional decline and weight are linked with poorer patient outcomes. This study retrospectively analyzed the impact of peri-operative nutritional status (as assessed by patient-generated subjective global assessment, PG-SGA), and weight loss on the survival of patients undergoing curative surgery for GOC (2013 to 2022). Of the 148 patients who underwent surgery, PG-SGA and weight data were available for 107 (72%) and 121 (82%), respectively. At presentation, 44% (n = 47) of patients were well nourished, dropping to 17% (n = 18) post-operatively. Lower post-operative nutritional status correlated to worse overall survival (OS) (p < 0.001). Patients who stayed well nourished or improved their nutritional status had better survival outcomes (HR: 2.7; 95%CI: 1.2–6.1; p = 0.01). Significant weight loss (>10%) was ubiquitously observed in 54% (n = 64) of patients, and this group had shorter OS (HR: 2.2; 95%CI: 1.2–4.1; p = 0.009). In conclusion, both nutritional decline and weight loss negatively impacted survival. Maintenance of nutritional status over the peri-operative period resulted in better outcomes. This study highlights the need for improved nutritional support during curative treatment in GOC.