Tumor-Infiltrating Immune Cells and PD-L1 as Prognostic Biomarkers in Primary Esophageal Small Cell Carcinoma

Role of stromal PD-L1 expression in colorectal liver metastasis

BACKGROUND AND AIM

The outcomes of immune checkpoint blockade for colorectal cancer (CRC) treatment are unsatisfactory. Furthermore, the efficacy of immune checkpoint blockade for liver metastasis of various cancer is poor. Here, we investigated the relationship between stromal programmed death-ligand 1 (PD-L1) expression and the prognosis of patients with colorectal cancer liver metastasis (CRLM).

METHODS

The present study enrolled 84 CRLM patients who underwent surgery (R0) for CRC. Immunohistochemistry was performed to analyze stromal PD-L1 expression in CRLM.

RESULTS

Stromal PD-L1 was expressed in 52.3% of CRLM samples, which was associated with fewer not optimally resectable metastases (p = 0.04). Stromal PD-L1 also tended to associate with a lower tumor grade (p = 0.08). Stromal PD-L1-positive patients had longer overall survival (p = 0.003). Multivariate analysis identified stromal PD-L1 expression (p = 0.008) and poorer differentiation (p < 0.001) as independent prognostic indicators. Furthermore, stromal PD-L1 expression was correlated to a high number of tumor-infiltrating lymphocytes (TILs). Stromal PD-L1- and low TIL groups had shorter OS than stromal PD-L1 + and high TIL groups (46.6% vs. 81.8%, p = 0.05) Stromal PD-L1-positive patients had longer disease-free survival (DFS) (p = 0.03) and time to surgical failure (p = 0.001). Interestingly, stromal PD-L1 expression was positively related to the desmoplastic subtype (p = 0.0002) and inversely related to the replacement subtype of the histological growth pattern (p = 0.008).

CONCLUSIONS

Stromal PD-L1 expression may be a significant prognostic marker for CRLM.

Opportunities and challenges in combining immunotherapy and radiotherapy in esophageal cancer

BACKGROUND

Immunotherapy has shown promise in the treatment of esophageal cancer, but using it alone only benefits a small number of patients. Most patients either do not have a significant response or develop secondary drug resistance. The combination of radiotherapy and immunotherapy appears to be a promising approach to treating esophageal cancer.

PURPOSE

We reviewed milestone clinical trials of radiotherapy combined with immunotherapy for esophageal cancer. We then discussed potential biomarkers for radiotherapy combined with immunotherapy, including programmed cell death-ligand 1 (PD-L1) status, tumor mutation burden (TMB), tumor-infiltrating lymphocytes, ct-DNA, imaging biomarkers, and clinical factors. Furthermore, we emphasize the key mechanisms of radiation therapy-induced immune stimulation and immune suppression in order to propose strategies for overcoming immune resistance in radiation therapy (RT). Lastly, we discussed the emerging role of low-dose radiotherapy (LDRT) , which has become a promising approach to overcome the limitations of high-dose radiotherapy.

CONCLUSION

Radiotherapy can be considered a triggering factor for systemic anti-tumor immune response and, with the assistance of immunotherapy, can serve as a systemic treatment option and potentially become the standard treatment for cancer patients.

Systemic treatments for resectable carcinoma of the esophagus

One of the most prevalent malignancies in the world is esophageal cancer (EC). The 5-year survival rate of EC remains pitiful despite treatment advancements. Neoadjuvant chemoradiotherapy in conjunction with esophagectomy is the standard of care for patients with resectable disease. The pathological complete response rate, however, is not acceptable. A distant metastasis or a locoregional recurrence will occur in about half of the patients. To increase the clinical effectiveness of therapy, it is consequently vital to investigate cutting-edge and potent therapeutic modalities. The approach to the management of resectable EC using immunotherapy has been considerably altered by immune checkpoint inhibitors. Systemic immunotherapy has recently been shown to have the potential to increase the survival of patients with resectable EC, according to growing clinical data. A combination of chemotherapy, radiation, and immunotherapy may have a synergistic antitumor impact because, according to mounting evidence, these treatments can stimulate the immune system via a number of different pathways. In light of this, it makes sense to consider the value of neoadjuvant immunotherapy for patients with surgically treatable EC. In this review, we clarify the rationale for neoadjuvant immunotherapy in resectable EC patients, recap the clinical outcomes of these approaches, go through the upcoming and ongoing investigations, and emphasize the difficulties and unmet research requirements.

Clinicopathological features, treatment modalities, and prognosis of esophageal neuroendocrine carcinoma: A single-center retrospective study

OBJECTIVES

Esophageal neuroendocrine carcinoma (ENEC) is a rare cancer that is highly malignant and related to a poor prognosis. In this retrospective study we aimed to elucidate the clinical characteristics, diagnosis and management of patients with ENEC and to evaluate the potential prognostic factors.

METHODS

Altogether 82 patients diagnosed with ENEC between January 2009 and December 2020 at the Fudan University Shanghai Cancer Center were retrospectively enrolled. Patients' survival was analyzed using the Kaplan-Meier and log-rank methods. Univariate and multivariate analyses and a Cox regression model were used to identify the prognostic factors.

RESULTS

The median overall survival (mOS) was 13 months in all patients. Multivariate analysis revealed that advanced tumor stage (hazard ratio [HR] 2.67, 95% confidence interval [CI] 1.07-6.66, P = 0.0353), liver (HR 3.36, 95% CI 1.53-7.41, P = 0.0026) and lung metastasis (HR 3.37, 95% CI 1.20-9.51, P = 0.0214) were associated with a poor prognosis. While positive chromogranin A (CgA) expression was related to a favorable outcome (HR 0.21, 95% CI 0.09-0.49, P < 0.001). Also, patients had adjustment of chemotherapy (dose reduction or less than three cycles) were prone to a worse prognosis compared with those did not (HR 4.36, 95% CI 2.10-9.08, P < 0.001).

CONCLUSION

In patients with ENEC, advanced cancer stage, adjustment of chemotherapy, liver and lung metastasis were associated with a poor survival, while CgA expression was related to a favorable prognosis.

TNFSF15 and MIA Variant Associated with Immunotherapy and Prognostic Evaluation in Esophageal Cancer

Background

Esophageal cancer (ESCA) is a common gastrointestinal tumor, and China is one of the regions with a high incidence. Tumor immune-related cells play important roles in the tumorigenesis and development of ESCA. However, the role of tumor immune-related genes in the development of ESCA has not been established.

Methods

In this study, weighted gene coexpression network analysis (WGCNA) was used to analyze ESCA gene expression using data from The Cancer Genome Atlas (TCGA) database. Gene expression was associated with clinical traits, and modules related to CD8+T cells, dendritic cells, and regulatory T cells (Tregs) were obtained.

Results

The GO analysis showed that inflammatory chemotaxis networks were activated by cell chemotaxis, chemokine activity, and chemokine binding receptor. Three hub genes (IL17C, TNFSF15, and MIA) related to tumor immunity and metastasis were identified by WGCNA, and the abnormal expression of each hub gene in ESCA has a poor prognosis, especially in patients with high expression (P < 0.05). The risk assessment analysis also showed that tumor stage was positively correlated with tumor risk in ESCA (P < 0.05). Therefore, more than 50 pairs of tumor tissues from the T1-T3 stages with different degrees of differentiation and paracancerous tissues were selected to confirm the expression of the three genes using RT-qPCR and immunofluorescence (IF). The infiltration of CD8+ T cells in tumor tissues was lower than that in normal tissues. According to the RT-qPCR, the expressions of IL17 C, TNFSF15, and MIA in moderately and poorly differentiated tissues were significantly higher than those in normal tissues (P < 0.05). In contrast, their expressions were decreased in high differentiated tissues (P < 0.05). Furthermore, IL17C, TNFSF15, and MIA were all positively correlated with immune checkpoint PD-1; TNFSF15 and MIA were also positively correlated with CTLA4, TIGIT, and CD96.

Conclusion

In summary, IL17C, TNFSF15, and MIA may act as biomarkers for prognosis in moderately and poorly differentiated ESCAs, and they may be used as predictive genes of immunotherapy associated with CD8+ T cell and Tregs invasion in ESCAs.

Treatments for resectable esophageal cancer: from traditional systemic therapy to immunotherapy

ABSTRACT

Esophageal cancer (EC) has a high incidence and poor prognosis. The two major histological types, squamous cell carcinoma and adenocarcinoma, differ in their epidemiology and treatment options. Patients with locally advanced EC benefit from multimodal therapy concepts including neoadjuvant chemotherapy, neoadjuvant chemoradiotherapy, and perioperative chemotherapy. Currently, immunotherapy for the solid tumor is a hot spot. Treatment with adjuvant immune checkpoint inhibitors (ICIs) is the first immunotherapy for resectable EC listed in the latest National Comprehensive Cancer Network Guidelines for the Esophageal and Esophagogastric Junction Cancers. Recent clinical trials have established ICIs for three treatment models of resectable EC. Their short-term results demonstrated ideal efficacy and tolerable toxicity, though some concerns remain. This review summarizes the novel data on the ICIs for resectable EC and lists the registered related clinical trials. Hopefully, this review can provide a reference for ongoing research on the treatment options for resectable EC.

The role of the immunoescape in colorectal cancer liver metastasis

The expression of programmed death 1 (PD-1) and programmed death-ligand 1 (PD-L1) indicate the efficacy of anti-PD-1/PD-L1 therapy in colorectal cancer (CRC), but are less useful for monitoring the efficacy of therapy of CRC liver metastasis (CRLM). This study investigated the effects of immune molecules on the prognosis of CRLM. We enrolled 71 patients with CRLM who underwent curative resection for CRC. We used immunohistochemistry to analyze the expression of PD-1, PD-L1, indoleamine-pyrrole 2,3-dioxygenase (IDO), and CD163 (a marker of tumor-associated macrophages [TAMs]) in metastatic tumors. The immune molecules PD-1, PD-L1, IDO, and TAMs were expressed in 32.3%, 47.8%, 45.0%, and 47.9% of metastatic CRC samples, respectively. The 5-year overall survival rates associated with immune molecule-positive groups were significantly better than in the negative groups (PD-1: 87.7% vs 53.2%, p = 0.023; PD-L1: 82.4% vs 42.3%, p = 0.007; IDO: 80.7% vs 43.5%, p = 0.007; TAMs: 82.6% vs 48.0%, p = 0.005). Multivariate analysis revealed PD-1 expression (p = 0.032, hazard ratio: 0.19), IDO expression (p = 0.049, hazard ratio: 0.37), and tumor differentiation (p<0.001, hazard ratio: 0.02) as independent prognostic indicators. PD-1 and TAMs in metastases were associated with less aggressive features such as smaller tumors. Furthermore, TAMs positively and significantly correlated with PD-1 expression (p = 0.011), PD-L1 expression (p = 0.024), and tended to correlate with IDO expression (p = 0.078). PD-1, PD-L1, IDO, and TAMs in CRLM were associated with less aggressive features and better prognosis of patients with CRC, indicating adaptive antitumor immunity vs immune tolerance. These molecules may therefore serve as prognostic markers for CRLM.

Comprehensive Analysis of Hexokinase 2 Immune Infiltrates and m6A Related Genes in Human Esophageal Carcinoma

Background: Hexokinase 2 not only plays a role in physiological function of human normal tissues and organs, but also plays a vital role in the process of glycolysis of tumor cells. However, there are few comprehensive studies on HK2 in esophageal carcinoma (ESCA) needs further study.

Methods: Oncomine, Tumor Immune Estimation Resource (TIMER), The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database were used to analyze the expression differences of HK2 in Pan-cancer and ESCA cohort, and to analyze the correlation between HK2 expression level and clinicopathological features of TCGA ESCA samples. GO/KEGG, GGI, and PPI analysis of HK2 was performed using R software, LinkedOmics, GeneMANIA and STRING online tools. The correlation between HK2 and ESCA immune infiltration was analyzed TIMER and TCGA ESCA cohort. The correlation between HK2 expression level and m6A modification of ESCA was analyzed by utilizing TCGA ESCA cohort.

Results: HK2 is highly expressed in a variety of tumors, and its high expression level in ESCA is closely related to the weight, cancer stages, tumor histology and tumor grade of ESCA. The analysis results of GO/KEGG showed that HK2 was closely related to cell adhesion molecule binding, cell-cell junction, ameboidal-type cell migration, insulin signaling pathway, hif-1 signaling pathway, and insulin resistance. GGI showed that HK2 associated genes were mainly involved in the glycolytic pathway. PPI showed that HK2 was closely related to HK1, GPI, and HK3, all of which played an important role in tumor proliferation. The analysis results of TIMER and TCGA ESCA cohort indicated that the HK2 expression level was related to the infiltration of various immune cells. TCGA ESCA cohort analyze indicated that the HK2 expression level was correlated with m6A modification genes.

Conclusion: HK2 is associated with tumor immune infiltration and m6A modification of ESCA, and can be used as a potential biological target for diagnosis and therapy of ESCA.

m6A Regulators Is Differently Expressed and Correlated With Immune Response of Esophageal Cancer

N6 methyladenosine (m6A) RNA methylation regulators play an important role in the development of tumors. However, their function in esophageal cancer (EC) has not been fully elucidated. Here, we analyzed the gene expression data of 24 major m6A RNA methylation regulators from 775 patients with EC from TCGA dataset. The present study showed the aberrations of m6A regulators in genome were correlated to prognosis in human ECs. Meanwhile, 17 m6A regulators showed increased expression in EC samples, including YTHDC1, IGF2BP2, FTO, METTL14, YTHDF3, RBM15, WTAP, HNRNPA2B1, HNRNPC, ALKBH5, YTHDF2, METTL16, IGF2BP3, VIRMA, RBM15B, YTHDF1, KIAA1429, HAKAI, and ZC3H13. Among them, we found HNRNPC, YTHDC2, WTAP, VIRMA, IGF2BP3, and HNRNPA2B1 were significantly correlated to worse outcomes and advanced stage in EC. Furthermore, we showed levels of m6A regulators is correlated with the expression of Immuno-regulators (Immunoinhibitors, Immunostimulators, and MHC molecules) and immune infiltration levels in EC. Bioinformatics further confirm m6A regulators were involved in regulating RNA splicing, RNA stability, and cell proliferation. Our study showed m6A regulators are promising targets and biomarkers for cancer immunotherapy in EC.