Podocalyxin-like protein as a predictive biomarker for benefit of neoadjuvant chemotherapy in resectable gastric and esophageal adenocarcinoma

Prognostic, Diagnostic and Predictive Biomarkers in the Barrett’s Oesophagus-Adenocarcinoma Disease Sequence

Simple Summary

Oesophageal adenocarcinoma (OAC) is a type of cancer of the oesophagus (food pipe) which is associated with poor patient outcomes. Barrett’s oesophagus (BO) is a precancerous condition of the oesophagus associated with chronic heartburn. Currently, surveillance programs exist which monitor patients with BO to prevent it from developing into OAC. However, these surveillance programs are expensive and unpleasant for patients. Prognostic biomarkers are signs which could be measured to determine the chance of someone with BO developing OAC, allowing more targeted surveillance. Similarly, diagnostic biomarkers are indicators which could be measured to see if someone has OAC. Developing new diagnostic biomarkers could allow wider population testing. Only a small proportion of patients with OAC respond to treatment before surgery. Predictive biomarkers could be measured to predict whether someone would respond to the treatments, allowing more individualized therapy. This review focuses on potential biomarkers which could improve patient outcomes in BO/OAC.

Abstract

Oesophageal adenocarcinoma (OAC) incidence has increased dramatically in the developed world, yet outcomes remain poor. Extensive endoscopic surveillance programs among patients with Barrett’s oesophagus (BO), the precursor lesion to OAC, have aimed to both prevent the development of OAC via radiofrequency ablation (RFA) and allow earlier detection of disease. However, given the low annual progression rate and the costs of endoscopy/RFA, improvement is needed. Prognostic biomarkers to stratify BO patients based on their likelihood to progress would enable a more targeted approach to surveillance and RFA of high-risk precursor lesions, improving the cost–risk–benefit ratio. Similarly, diagnostic biomarkers for OAC could enable earlier diagnosis of disease by allowing broader population screening. Current standard treatment for locally advanced OAC includes neoadjuvant chemotherapy (+/− radiotherapy) despite only a minority of patients benefiting from neoadjuvant treatment. Accordingly, biomarkers predictive of response to neoadjuvant therapy could improve patient outcomes by reducing time to surgery and unnecessary toxicity for the patients who would have received no benefit from the therapy. In this mini-review, we will discuss the emerging biomarkers which promise to dramatically improve patient outcomes along the BO-OAC disease sequence.

High Infiltration of CD68+/CD163- Macrophages Is an Adverse Prognostic Factor after Neoadjuvant Chemotherapy in Esophageal and Gastric Adenocarcinoma

Tumor-associated macrophages (TAMs) have emerged as key players in tumor immunology but demonstrate a continuum of functional states being either tumor suppressive or promoting. Moreover, chemotherapeutic agents have been shown to alter the tumor microenvironment. Perioperative chemotherapy is a standard treatment option for resectable esophageal and gastric (EG) adenocarcinoma. The aim of this study was to investigate the influence of neoadjuvant chemotherapy (NAC) on TAMs to improve the prognostication and treatment course for these patients. The study cohort comprised 148 patients, all of whom were diagnosed with resectable EG adenocarcinoma and treated with NAC. Immunohistochemistry was applied to assess the total infiltration and infiltration into tumor nests (TN) of CD68+/CD163-, CD68+/CD163+, and MARCO+ TAMs, on paired biopsies from primary tumors (PT) pre-NAC, and resected PT and lymph node metastases post-NAC. In pre-NAC specimens, high CD68+/CD163+ infiltration into TN was an unfavorable prognostic factor. No association was found between TAM density in PT pre-NAC and histopathological regression. The density of CD68+/CD163+ TAMs was increased in PT post-NAC, while the density of MARCO+ TAMs was decreased. CD68+/CD163- TAM density was not altered. In post-NAC specimens, higher total as well as TN infiltration of CD68+/CD163- TAMs were adverse prognostic factors. In conclusion, these results suggest that NAC may alter certain TAM subsets in EG adenocarcinoma, along with their functional properties and thus their prognostic value.

Biomarkers for the prediction of esophageal cancer neoadjuvant chemoradiotherapy response: A systemic review

Neoadjuvant chemoradiotherapy followed by surgery has been established as the standard treatment for locally advanced esophageal cancer. For patients with complete regression after neoadjuvant chemotherapy, active surveillance rather than planned surgery has been proposed as an organ preservation strategy. Reliable biomarkers to predict chemoradiation response is needed. We first summarized the previous reports of biomarkers with the potential to predict the treatment response of esophageal cancer neoadjuvant chemoradiotherapy. These traditional biomarkers are classified into three groups: genetic biomarkers, RNA biomarkers, and protein biomarkers. We then summarized some special types of biomarkers, including metabolites biomarkers, immune and tumor microenvironment biomarkers, and microbiome biomarkers.

T cells, B cells, and PD-L1 expression in esophageal and gastric adenocarcinoma before and after neoadjuvant chemotherapy: relationship with histopathological response and survival

Perioperative chemotherapy enhances the survival rates for patients with esophageal and gastric (EG) adenocarcinoma, but not all patients benefit from this additional treatment. Chemotherapeutic agents have been demonstrated to alter the immune cell (IC) composition in the tumor microenvironment. Hence, there is a rationale to investigate the influence of neoadjuvant chemotherapy (NAC) on different IC subsets, to better understand and compare their utility as complementary prognostic or predictive biomarkers in a clinically relevant context. The density of T cells (CD8⁺ and FoxP3⁺), B cells (CD20⁺) and the expression of PD-L1 on ICs and tumor cells (TC) was assessed by immunohistochemistry on paired biopsies from primary tumors (PT) pre-NAC, and resected PT and lymph node metastases post-NAC. The cohort encompasses 148 patients with resectable EG adenocarcinoma, all of whom received NAC. The density of CD8⁺ cells was decreased and the density of FoxP3⁺ cells and CD20⁺ cells was increased in PT post-NAC. PD-L1 expression was not altered following NAC. In pre-NAC specimens, high FoxP3⁺ density and high PD-L1 expression on ICs were favorable prognostic factors, whereas high CD8⁺ density was an unfavorable prognostic factor. In post-NAC specimens, however, high FoxP3⁺ density was an unfavorable prognostic factor, and high PD-L1 expression on TC was associated with a shorter survival. There were no significant associations between IC density or PD-L1 expression in PT pre-NAC and histopathological regression. These findings propose that NAC might alter the density and prognostic impact of some IC subsets in EG adenocarcinoma.

CTCF-induced upregulation of LINC01207 promotes gastric cancer progression via miR-1301-3p/PODXL axis

BACKGROUND

Long non coding RNAs (lncRNAs) have been validated to be involved in the complicated biological processes during tumor progression. LINC01207 has been identified as an oncogene in several cancer types. However, the function of LINC01207 and its underlying molecular mechanism in gastric cancer (GC) are poorly understood.

METHODS

The expression level of LINC01207, miR-1301-3p and PODXL mRNA was detected in GC tissues and cells by RT-qPCR. The level of PODXL protein was examined by western blot. Colony formation assay, EdU assay, TUNEL assay, caspase-3 activity test and transwell assays were carried out to analyze the effect of LINC01207 on GC cell proliferation, apoptosis, migration and invasion. The interaction between RNAs was confirmed by luciferase reporter assay, RNA pull-down assay and RIP assay.

RESULTS

LINC01207 was expressed at high level in GC tissues and cells. Silencing of LINC01207 impaired GC cell proliferation, migration and invasion but promoted cell apoptosis. Mechanistically, LINC01207 acted as a ceRNA by sponging miR-1301-3p to upregulate PODXL. Besides, miR-1301-3p silencing or PODXL overexpression could abolish the inhibitory effect of LINC01207 knockdown on GC cell growth and migration. CCCTC-binding factor (CTCF) could transcriptionally activate LINC01207 in GC cells.

CONCLUSIONS

CTCF-induced activation of LINC01207 contributes to GC progression through regulating miR-1301-3p/PODXL axis.

PODXL might be a new prognostic biomarker in various cancers: a meta-analysis and sequential verification with TCGA datasets

ABSRACT

BACKGROUND: Several studies have investigated the associations between the podocalyxin-like protein (PODXL) expression quantity or locations and cancers survival, but the results were far from conclusive. Therefore, we proceeded a meta-analysis on PODXL in various human cancers to find its prognostic value and followed confirmation using the TCGA datasets.

METHODS

We performed a systematic search, and 18 citations, including 5705 patients were pooled in meta-analysis. The results were verified with TCGA datasets.

RESULTS

Total eligible studies comprised 5705 patients with 10 types of cancer. And the result indicated that PODXL high-expression or membrane-expression were significantly related to poor overall survival (OS). However, subgroup analysis showed a significant association between high expressed PODXL and poor OS in the colorectal cancer, pancreatic cancer, urothelial bladder cancer, renal cell carcinoma and glioblastoma multiforme. Then, we validated the inference using TCGA datasets, and the consistent results were demonstrated in patients with pancreatic cancer, glioblastoma multiforme, gastric cancer, esophageal cancer and lung adenocarcinoma.

CONCLUSION

The result of meta-analysis showed that high expressed PODXL was significantly linked with poor OS in pancreatic cancer and glioblastoma multiforme, but not in gastric cancer, esophageal cancer or lung adenocarcinoma. And the membrane expression of PODXL might also associate with poor OS. PODXL may act as tumor promotor and may serve as a potential target for antitumor therapy.

NNT-AS1 enhances bladder cancer cell growth by targeting miR-1301-3p/PODXL axis and activating Wnt pathway

As a tumor involved in the urinary system, bladder cancer (BC) seriously threatens human health. Emerging as crucial biomarkers, long noncoding RNAs (lncRNAs) play an important role in the regulation of many cancers. lncRNA NNT-AS1 has been studied in a series of cancers, whereas its role and potential molecular mechanism was poorly understood in BC. Here, we found that NNT-AS1 was upregulated in BC cells. Functionally, the silencing of NNT-AS1 inhibited cell proliferation, migration, invasion, and endothelial-mesenchymal transition. Furthermore, the apoptosis of BC cells was induced upon NNT-AS1 knockdown. Later, miR-1301-3p, the downstream gene of NNT-AS1, was found at a low level in BC cells. In addition, we found that miR-1301-3p targeted to PODXL. PODXL expression downregulated in NNT-AS1-silenced cells was restored by miR-1301-3p inhibition. Importantly, NNT-AS1 was discovered to activate Wnt pathway, and the treatment of LiCl recovered the repressive role of NNT-AS1 silencing in BC cell growth. Through restoration assays, we observed that PODXL overexpressing countervailed NNT-AS1 depletion-mediated suppression on BC cell growth and Wnt pathway. These data suggested that NNT-AS1 enhances BC cell growth and activates Wnt pathway by targeting miR-1301-3p/PODXL axis.