Role of myeloid-derived suppressor cells in metastasis

Advances in targeting tumor microenvironment for immunotherapy

The tumor microenvironment (TME) provides essential conditions for the occurrence, invasion, and spread of cancer cells. Initial research has uncovered immunosuppressive properties of the TME, which include low oxygen levels (hypoxia), acidic conditions (low pH), increased interstitial pressure, heightened permeability of tumor vasculature, and an inflammatory microenvironment. The presence of various immunosuppressive components leads to immune evasion and affects immunotherapy efficacy. This indicates the potential value of targeting the TME in cancer immunotherapy. Therefore, TME remodeling has become an effective method for enhancing host immune responses against tumors. In this study, we elaborate on the characteristics and composition of the TME and how it weakens immune surveillance and summarize targeted therapeutic strategies for regulating the TME.

Mechanism insights and therapeutic intervention of tumor metastasis: latest developments and perspectives

Metastasis remains a pivotal characteristic of cancer and is the primary contributor to cancer-associated mortality. Despite its significance, the mechanisms governing metastasis are not fully elucidated. Contemporary findings in the domain of cancer biology have shed light on the molecular aspects of this intricate process. Tumor cells undergoing invasion engage with other cellular entities and proteins en route to their destination. Insights into these engagements have enhanced our comprehension of the principles directing the movement and adaptability of metastatic cells. The tumor microenvironment plays a pivotal role in facilitating the invasion and proliferation of cancer cells by enabling tumor cells to navigate through stromal barriers. Such attributes are influenced by genetic and epigenetic changes occurring in the tumor cells and their surrounding milieu. A profound understanding of the metastatic process's biological mechanisms is indispensable for devising efficacious therapeutic strategies. This review delves into recent developments concerning metastasis-associated genes, important signaling pathways, tumor microenvironment, metabolic processes, peripheral immunity, and mechanical forces and cancer metastasis. In addition, we combine recent advances with a particular emphasis on the prospect of developing effective interventions including the most popular cancer immunotherapies and nanotechnology to combat metastasis. We have also identified the limitations of current research on tumor metastasis, encompassing drug resistance, restricted animal models, inadequate biomarkers and early detection methods, as well as heterogeneity among others. It is anticipated that this comprehensive review will significantly contribute to the advancement of cancer metastasis research.

Effects of the subtypes of apolipoprotein E on immune inhibition and prognosis in patients with Hepatocellular Carcinoma

PURPOSE

To investigate whether prognosis of patients with hepatocellular carcinoma (HCC) is affected by the abundance and subgroups of myeloid-derived suppressor cells (MDSCs) as well as subtypes and expression of apolipoprotein E (apoE).

METHODS

31 HCC patients were divided into three groups according to blood total apoE level for detecting the abundance of immunoregulatory cells by flow cytometry. Tumour tissue microarrays from 360 HCC patients were evaluated about the abundance and subgroups of MDSCs and the expression of apoE2, apoE3, apoE4 by immunofluorescence staining and immunohistochemistry staining. Survival analysis by means of univariate, multivariate COX regression and Kaplan-Meier methods of the 360 patients was performed based on clinical and pathological examinations along with 10 years' follow-up data.

RESULTS

The lower apoE group presented higher abundance of MDSCs in the peripheral blood of HCC patients than higher apoE group. The abundance of monocyte-like MDSCs (M-MDSCs) was higher in the apoE low level group than high level group (p = 0.0399). Lower H-score of apoE2 (HR = 6.140, p = 0.00005) and higher H-score of apoE4 (HR = 7.001, p = 0.009) in tumour tissue were significantly associated with shorter overall survival (OS). The higher infiltration of polymorphonuclear granulocyte-like MDSCs (PMN-MDSCs, HR = 3.762, p = 0.000009) and smaller proportion of M-MDSCs of total cells (HR = 0.454, p = 0.006) in tumour tissue were independent risk factors for shorter recurrence-free survival (RFS).

CONCLUSION

The abundance of MDSCs in HCC patients' plasma negatively correlates with the level of apoE. The expression of apoE4 in HCC tissue indicated a poor prognosis while apoE2 might be a potential protective factor.

Hepatitis B virus-related hepatocellular carcinoma exhibits distinct intratumoral microbiota and immune microenvironment signatures

Emerging evidence supports a high prevalence of cancer type-specific microbiota residing within tumor tissues. The intratumoral microbiome in hepatocellular carcinoma (HCC), especially in viral (hepatitis B virus [HBV]/hepatitis C virus [HCV]) HCC, has not been well characterized for their existence, composition, distribution, and biological functions. We report herein a finding of specific microbial signature in viral HCC as compared to non-HBV/non-HCV (NBNC) HCC. However, the significantly diverse tumor microbiome was only observed in HBV-related HCC, and Cutibacterium was identified as the representative taxa biomarker. Biological function of the unique tumor microbiota in modulating tumor microenvironment (TME) was characterized by using formalin-fixed paraffin-embedded (FFPE) tissue-based multiplex immunofluorescence histochemistry (mIFH) allowing simultaneous in situ detection of the liver cancer cells surrounded with high/low density of microbiota, and the infiltrating immune cells. In HBV_HCC, the intratumoral microbiota are positively associated with increased tumor-infiltrating CD8+ T lymphocytes, but not the CD56+ NK cells. Two subtypes of myeloid-derived suppressor cells (MDSCs): monocytic MDSCs and polymorphonuclear MDSCs, were also found to be positively correlated with the intratumoral microbiota in HBV_HCC, indicating an inhibitory role of these microbial species in antitumor immunity and the contribution to the liver TME in combination of chronic viral hepatitis during HCC development.

MicroRNAs mediated interaction of tumor microenvironment cells with breast cancer cells during bone metastasis

Breast cancer (BC) bone metastasis is primarily osteolytic and has limited therapeutic options. Metastasized BC cells prime the secondary environment in bone by forming a tumor niche, which favors their homing and colonization. The tumor microenvironment (TME) is primarily generated by the cancer cells. Bone TME is an intricate network of multiple cells, including altered bone, tumor, stromal, and immune cells. Recent findings highlight the significance of small non-coding microRNAs (miRNAs) in influencing TME during tumor metastasis. MiRNAs from TME-resident cells facilitate the interaction between the tumor and its microenvironment, thereby regulating the biological processes of tumors. These miRNAs can serve as oncogenes or tumor suppressors. Hence, both miRNA inhibitors and mimics are extensively utilized in pre-clinical trials for modulating the phenotypes of tumor cells and associated stromal cells. This review briefly summarizes the recent developments on the functional role of miRNAs secreted directly or indirectly from the TME-resident cells in facilitating tumor growth, progression, and metastasis. This information would be beneficial in developing novel targeted therapies for BC.

Galectin-1 Mediates Chronic STING Activation in Tumors to Promote Metastasis through MDSC Recruitment

The immune system plays a crucial role in the regulation of metastasis. Tumor cells systemically change immune functions to facilitate metastatic progression. Through this study, we deciphered how tumoral galectin-1 (Gal1) expression shapes the systemic immune environment to promote metastasis in head and neck cancer (HNC). In multiple preclinical models of HNC and lung cancer in immunogenic mice, Gal1 fostered the establishment of a premetastatic niche through polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC), which altered the local microenvironment to support metastatic spread. RNA sequencing of MDSCs from premetastatic lungs in these models demonstrated the role of PMN-MDSCs in collagen and extracellular matrix remodeling in the premetastatic compartment. Gal1 promoted MDSC accumulation in the premetastatic niche through the NF-κB signaling axis, triggering enhanced CXCL2-mediated MDSC migration. Mechanistically, Gal1 sustained NF-κB activation in tumor cells by enhancing stimulator of interferon gene (STING) protein stability, leading to prolonged inflammation-driven MDSC expansion. These findings suggest an unexpected protumoral role of STING activation in metastatic progression and establish Gal1 as an endogenous-positive regulator of STING in advanced-stage cancers.

SIGNIFICANCE

Galectin-1 increases STING stability in cancer cells that activates NF-κB signaling and CXCL2 expression to promote MDSC trafficking, which stimulates the generation of a premetastatic niche and facilitates metastatic progression.

Updating the therapeutic role of ginsenosides in breast cancer: a bibliometrics study to an in-depth review

Breast cancer is currently the most common malignancy and has a high mortality rate. Ginsenosides, the primary bioactive constituents of ginseng, have been shown to be highly effective against breast cancer both in vitro and in vivo. This study aims to comprehensively understand the mechanisms underlying the antineoplastic effects of ginsenosides on breast cancer. Through meticulous bibliometric analysis and an exhaustive review of pertinent research, we explore and summarize the mechanism of action of ginsenosides in treating breast cancer, including inducing apoptosis, autophagy, inhibiting epithelial-mesenchymal transition and metastasis, and regulating miRNA and lncRNA. This scholarly endeavor not only provides novel prospects for the application of ginsenosides in the treatment of breast cancer but also suggests future research directions for researchers.

Evaluation of the anti-proliferative activity of 2-oxo-pyridine and 1′H-spiro-pyridine derivatives as a new class of EGFRWt and VEGFR-2 inhibitors with apoptotic inducers†

Developing new agents for cancer treatment remains a top priority because it is one of the deadliest worldwide. A new series of 2-oxo-pyridine and 1′H-spiro-pyridine derivatives were designed and synthesized based on an N-(ethyl benzoate) moiety. The structure of the designed derivatives was confirmed by different spectroscopic techniques (FT-IR and NMR) and elemental analysis and then evaluated as antiproliferative against HepG-2 and Caco-2 cell lines compared with Doxorubicin. The spiro-pyridine derivatives 5, 7, and 8 exhibited a remarkably higher activity against Caco-2 cell lines than that of other derivatives. Additionally, these derivatives exhibited activation in the Bax and suppressed Bcl-2 expression with variable degrees. Interestingly, compound 7 showed the lowest cytotoxicity value on Caco-2 cells (IC₅₀ = 7.83 ± 0.50 μM) compared with Doxorubicin (IC₅₀ = 12.49 ± 1.10 μM). Additionally, this compound showed activation of the Bax gene (7.508-fold) and suppressed Bcl-2 (0.194-fold) compared to untreated Caco-2 cells, as revealed by the qRT-PCR technique. Moreover, compound 7 could inhibit EGFR and VEGFR-2 with sub-micromole values of 0.124 μM and 0.221 μM compared with Erlotinib (IC₅₀ = 0.033 μM) and Sorafenib (IC₅₀ = 0.043 μM), respectively. Further, cell cycle and apoptosis analysis demonstrated that compound 7 promoted apoptosis by increasing the apoptosis rate from 1.92 to 42.35% and the S cell accumulation ratio from 31.18 to 42.07% compared to untreated Caco-2 cells. Finally, the most active compound 7 showed good drug-likeness and toxicity profiles. Besides, molecular docking studies were performed to determine the binding mode, which is in agreement with the in vitro results.

Design and synthesis a novel of 2-oxo-pyridine and 1′H-spiro-pyridine derivatives as a new apoptotic inducers agents.

Tumor microenvironment enriches the stemness features: the architectural event of therapy resistance and metastasis

Cancer divergence has many facets other than being considered a genetic term. It is a tremendous challenge to understand the metastasis and therapy response in cancer biology; however, it postulates the opportunity to explore the possible mechanism in the surrounding tumor environment. Most deadly solid malignancies are distinctly characterized by their tumor microenvironment (TME). TME consists of stromal components such as immune, inflammatory, endothelial, adipocytes, and fibroblast cells. Cancer stem cells (CSCs) or cancer stem-like cells are a small sub-set of the population within cancer cells believed to be a responsible player in the self-renewal, metastasis, and therapy response of cancer cells. The correlation between TME and CSCs remains an enigma in understanding the events of metastasis and therapy resistance in cancer biology. Recent evidence suggests that TME dictates the CSCs maintenance to arbitrate cancer progression and metastasis. The immune, inflammatory, endothelial, adipocyte, and fibroblast cells in the TME release growth factors, cytokines, chemokines, microRNAs, and exosomes that provide cues for the gain and maintenance of CSC features. These intricate cross-talks are fueled to evolve into aggressive, invasive, migratory phenotypes for cancer development. In this review, we have abridged the recent developments in the role of the TME factors in CSC maintenance and how these events influence the transition of tumor progression to further translate into metastasis and therapy resistance in cancer.

Recent progress in molecular mechanisms of postoperative recurrence and metastasis of hepatocellular carcinoma

Hepatectomy is currently considered the most effective option for treating patients with early and intermediate hepatocellular carcinoma (HCC). Unfortunately, the postoperative prognosis of patients with HCC remains unsatisfactory, predominantly because of high postoperative metastasis and recurrence rates. Therefore, research on the molecular mechanisms of postoperative HCC metastasis and recurrence will help develop effective intervention measures to prevent or delay HCC metastasis and recurrence and to improve the long-term survival of HCC patients. Herein, we review the latest research progress on the molecular mechanisms underlying postoperative HCC metastasis and recurrence to lay a foundation for improving the understanding of HCC metastasis and recurrence and for developing more precise prevention and intervention strategies.

Hazard Function Analysis of Recurrence in Patients with Curatively Resected Lung Cancer: Results from the Japanese Lung Cancer Registry in 2010

Simple Summary

To optimize postoperative surveillance of lung cancer patients, we investigated the hazard function of tumor recurrence in patients with completely resected lung cancer. Using the records of the 2010 Japanese Joint Committee of Lung Cancer Registry, the risk of postoperative recurrence was analyzed using a cause-specific hazard function in patients who underwent lobectomy to completely resect pathological stage I–III lung cancer. The hazard function for recurrence exhibited a peak at approximately 9 months after surgery, followed by a tapered plateau-like tail extending to 60 months. The peak risk for intrathoracic recurrence was approximately two-fold higher compared with that of extrathoracic recurrence. When considered together with the results of the subgroup analysis, the characteristics of the postoperative tumor recurrence hazard in a large cohort of lung cancer patients may be useful for improving stage-related management of postoperative surveillance.

Abstract

To optimize postoperative surveillance of lung cancer patients, we investigated the hazard function of tumor recurrence in patients with completely resected lung cancer. We analyzed the records of 12,897 patients in the 2010 Japanese Joint Committee of Lung Cancer Registry who underwent lobectomy to completely resect pathological stage I–III lung cancer. The risk of postoperative recurrence was determined using a cause-specific hazard function. The hazard function for recurrence exhibited a peak at approximately 9 months after surgery, followed by a tapered plateau-like tail extending to 60 months. The peak risk for intrathoracic recurrence was approximately two-fold higher compared with that of extrathoracic recurrence. Subgroup analysis showed that patients with stage IIIA adenocarcinoma had a continuously higher risk of recurrence compared with patients with earlier-stage disease. However, the risk of recurrence in patients with squamous cell carcinoma was not significantly different compared with that more than 24 months after surgery, regardless of pathological stage. In conclusion, the characteristics of postoperative tumor recurrence hazard in a large cohort of lung cancer patients may be useful for determining the time after surgery at which patients are at the highest risk of tumor recurrence. This information may improve stage-related management of postoperative surveillance.

Role of myeloid-derived suppressor cells in the formation of pre-metastatic niche

Metastasis is a complex process, which depends on the interaction between tumor cells and host organs. Driven by the primary tumor, the host organ will establish an environment suitable for the growth of tumor cells before their arrival, which is called the pre-metastasis niche. The formation of pre-metastasis niche requires the participation of a variety of cells, in which myeloid-derived suppressor cells play a very important role. They reach the host organ before the tumor cells, and promote the establishment of the pre-metastasis niche by influencing immunosuppression, vascular leakage, extracellular matrix remodeling, angiogenesis and so on. In this article, we introduced the formation of the pre-metastasis niche and discussed the important role of myeloid-derived suppressor cells. In addition, this paper also emphasized the targeting of myeloid-derived suppressor cells as a therapeutic strategy to inhibit the formation of pre-metastasis niche, which provided a research idea for curbing tumor metastasis.

Construction of an immune-related gene signature for the prognosis and diagnosis of glioblastoma multiforme

Background

Increasing evidence has suggested that inflammation is related to tumorigenesis and tumor progression. However, the roles of immune-related genes in the occurrence, development, and prognosis of glioblastoma multiforme (GBM) remain to be studied.

Methods

The GBM-related RNA sequencing (RNA-seq), survival, and clinical data were acquired from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), Chinese Glioma Genome Atlas (CGGA), and Gene Expression Omnibus (GEO) databases. Immune-related genes were obtained from the Molecular Signatures Database (MSigDB). Differently expressed immune-related genes (DE-IRGs) between GBM and normal samples were identified. Prognostic genes associated with GBM were selected by Kaplan-Meier survival analysis, Least Absolute Shrinkage and Selection Operator (LASSO)-penalized Cox regression analysis, and multivariate Cox analysis. An immune-related gene signature was developed and validated in TCGA and CGGA databases separately. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to explore biological functions of the signature. The correlation between immune cell infiltration and the signature was analyzed by single-sample gene set enrichment analysis (ssGSEA), and the diagnostic value was investigated. The gene set enrichment analysis (GSEA) was performed to explore the potential function of the signature genes in GBM, and the protein-protein interaction (PPI) network was constructed.

Results

Three DE-IRGs [Pentraxin 3 (PTX3), TNFSF9, and bone morphogenetic protein 2 (BMP2)] were used to construct an immune-related gene signature. Receiver operating characteristic (ROC) curves and Cox analyses confirmed that the 3-gene-based prognostic signature was a good independent prognostic factor for GBM patients. We found that the signature was mainly involved in immune-related biological processes and pathways, and multiple immune cells were disordered between the high- and low-risk groups. GSEA suggested that PTX3 and TNFSF9 were mainly correlated with interleukin (IL)-17 signaling pathway, nuclear factor kappa B (NF-κB) signaling pathway, tumor necrosis factor (TNF) signaling pathway, and Toll-like receptor signaling pathway, and the PPI network indicated that they could interact directly or indirectly with inflammatory pathway proteins. Quantitative real-time PCR (qRT-PCR) indicated that the three genes were significantly different between target tissues.

Conclusion

The signature with three immune-related genes might be an independent prognostic factor for GBM patients and could be associated with the immune cell infiltration of GBM patients.

Cell-Cell Interactions Drive Metastasis of Circulating Tumor Microemboli

Circulating tumor cells are the cellular mediators of distant metastasis in solid malignancies. Their metastatic potential can be augmented by clustering with other tumor cells or nonmalignant cells, forming circulating tumor microemboli (CTM). Cell-cell interactions are key regulators within CTM that convey enhanced metastatic properties, including improved cell survival, immune evasion, and effective extravasation into distant organs. However, the cellular and molecular mechanism of CTM formation, as well as the biology of interactions between tumor cells and immune cells, platelets, and stromal cells in the circulation, remains to be determined. Here, we review the current literature on cell-cell interactions in homotypic and heterotypic CTM and provide perspectives on therapeutic strategies to attenuate CTM-mediated metastasis by targeting cell-cell interactions.

Glucocorticoid receptor modulates myeloid-derived suppressor cell function via mitochondrial metabolism in immune thrombocytopenia

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature cells and natural inhibitors of adaptive immunity. Intracellular metabolic changes in MDSCs exert a direct immunological influence on their suppressive activity. Our previous study demonstrated that high-dose dexamethasone (HD-DXM) corrected the functional impairment of MDSCs in immune thrombocytopenia (ITP); however, the MDSC population was not restored in nonresponders, and the mechanism remained unclear. In this study, altered mitochondrial physiology and reduced mitochondrial gene transcription were detected in MDSCs from HD-DXM nonresponders, accompanied by decreased levels of carnitine palmitoyltransferase-1 (CPT-1), a rate-limiting enzyme in fatty acid oxidation (FAO). Blockade of FAO with a CPT-1 inhibitor abolished the immunosuppressive function of MDSCs in HD-DXM responders. We also report that MDSCs from ITP patients had lower expression of the glucocorticoid receptor (GR), which can translocate into mitochondria to regulate the transcription of mitochondrial DNA (mtDNA) as well as the level of oxidative phosphorylation. It was confirmed that the expression of CPT-1 and mtDNA-encoded genes was downregulated in GR-siRNA-treated murine MDSCs. Finally, by establishing murine models of active and passive ITP via adoptive transfer of DXM-modulated MDSCs, we confirmed that GR-silenced MDSCs failed to alleviate thrombocytopenia in mice with ITP. In conclusion, our study indicated that impaired aerobic metabolism in MDSCs participates in the pathogenesis of glucocorticoid resistance in ITP and that intact control of MDSC metabolism by GR contributes to the homeostatic regulation of immunosuppressive cell function.

Prolonged survival of anaplastic thyroid carcinoma is associated with resectability, low tumor-infiltrating neutrophils/myeloid-derived suppressor cells, and low peripheral neutrophil-to-lymphocyte ratio

PURPOSE

Anaplastic thyroid carcinoma (ATC) is the most lethal form of thyroid cancer with most patients dying of their disease within a few months. Only a very small percentage of long-term survivors (LTS) are alive for 2 years or longer. In this retrospective case-control study, we provided a comprehensive comparison between 46 ATC LTSs and 75 ATC control patients who suffered disease-specific mortality within 2 years, aiming to identify factors that may be associated with prolonged survival in ATC.

METHODS

A comprehensive clinicopathologic and molecular comparison was performed between 46 ATC LTSs and 75 ATC control patients. Peripheral neutrophil count and neutrophil-to-lymphocyte ratio (NLR) were recorded. The composition of the tumor microenvironment was compared using immunohistochemistry.

RESULTS

Compared with ATC control patients, ATC LTSs were characterized by 1) higher frequency of (primary) resection as well as clinicopathologic parameters attributed to resectability; 2) lower rate of concurrent RAS/BRAF and TERT promoter mutations; 3) lower peripheral neutrophil count and NLR; and 4) lower number of tumor-infiltrating neutrophils/myeloid-derived suppressor cells (MDSC). The survival benefits of low peripheral neutrophil counts and low NLR persisted even when controlling for distant metastasis status at presentation.

CONCLUSIONS

In addition to traditional beneficial prognostic factors, e.g., surgical resection, factors attributed to resectability, and absence of co-existing RAS/BRAF and TERT promoter mutations, we herein show that tumor-infiltrating and circulating neutrophils/MDSC are adverse prognostic factors in ATC.

Emerging Roles of Immune Cells in Cancer Development and Progression

Immune cells are a major constituent of the tumor microenvironment, and participate in interactions with tumor cells to promote the acquisition of critical hallmarks of cancer [...].

Splenic and PB immune recovery in neoadjuvant treated gastrointestinal cancer patients

In recent years, immune therapy, notably immune checkpoint inhibitors (ICI), in conjunction with chemotherapy and surgery has demonstrated therapeutic activity for some tumor types. However, little is known about the optimal combination of immune therapy with standard of care therapies and approaches. In patients with gastrointestinal (GI) cancers, especially pancreatic ductal adenocarcinoma (PDAC), preoperative (neoadjuvant) chemotherapy has increased the number of patients who can undergo surgery and improved their responses. However, most chemotherapy is immunosuppressive, and few studies have examined the impact of neoadjuvant chemotherapy (NCT) on patient immunity and/or the optimal combination of chemotherapy with immune therapy. Furthermore, the majority of chemo/immunotherapy studies focused on immune regulation in cancer patients have focused on postoperative (adjuvant) chemotherapy and are limited to peripheral blood (PB) and occasionally tumor infiltrating lymphocytes (TILs); representing a minority of immune cells in the host. Our previous studies examined the phenotype and frequencies of myeloid and lymphoid cells in the PB and spleens of GI cancer patients, independent of chemotherapy regimen. These results led us to question the impact of NCT on host immunity. We report herein, unique studies examining the splenic and PB phenotypes, frequencies, and numbers of myeloid and lymphoid cell populations in NCT treated GI cancer patients, as compared to treatment naïve cancer patients and patients with benign GI tumors at surgery. Overall, we noted limited immunological differences in patients 6 weeks following NCT (at surgery), as compared to treatment naive patients, supporting rapid immune normalization. We observed that NCT patients had a lower myeloid derived suppressor cells (MDSCs) frequency in the spleen, but not the PB, as compared to treatment naive cancer patients and patients with benign GI tumors. Further, NCT patients had a higher splenic and PB frequency of CD4+ T-cells, and checkpoint protein expression, as compared to untreated, cancer patients and patients with benign GI tumors. Interestingly, in NCT treated cancer patients the frequency of mature (CD45RO+) CD4+ and CD8+ T-cells in the PB and spleens was higher than in treatment naive patients. These differences may also be associated, in part with patient stage, tumor grade, and/or NCT treatment regimen. In summary, the phenotypic profile of leukocytes at the time of surgery, approximately 6 weeks following NCT treatment in GI cancer patients, are similar to treatment naive GI cancer patients (i.e., patients who receive adjuvant therapy); suggesting that NCT may not limit the response to immune intervention and may improve tumor responses due to the lower splenic frequency of MDSCs and higher frequency of mature T-cells.

Ductal Carcinoma in Situ: Molecular Changes Accompanying Disease Progression

Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive ductal carcinoma (IDC), whereby if left untreated, approximately 12% of patients develop invasive disease. The current standard of care is surgical removal of the lesion, to prevent potential progression, and radiotherapy to reduce risk of recurrence. There is substantial overtreatment of DCIS patients, considering not all DCIS lesions progress to invasive disease. Hence, there is a critical imperative to better predict which DCIS lesions are destined for poor outcome and which are not, allowing for tailored treatment. Active surveillance is currently being trialed as an alternative management practice, but this approach relies on accurately identifying cases that are at low risk of progression to invasive disease. Two DCIS-specific genomic profiling assays that attempt to distinguish low and high-risk patients have emerged, but imperfections in risk stratification coupled with a high price tag warrant the continued search for more robust and accessible prognostic biomarkers. This search has largely turned researchers toward the tumor microenvironment. Recent evidence suggests that a spectrum of cell types within the DCIS microenvironment are genetically and phenotypically altered compared to normal tissue and play critical roles in disease progression. Uncovering the molecular mechanisms contributing to DCIS progression has provided optimism for the search for well-validated prognostic biomarkers that can accurately predict the risk for a patient developing IDC. The discovery of such markers would modernize DCIS management and allow tailored treatment plans. This review will summarize the current literature regarding DCIS diagnosis, treatment, and pathology.

Immunophenotype Rearrangement in Response to Tumor Excision May Be Related to the Risk of Biochemical Recurrence in Prostate Cancer Patients

Background: Prostate cancer (PCa) is known to exhibit a wide spectrum of aggressiveness and relatively high immunogenicity. The aim of this study was to examine the effect of tumor excision on immunophenotype rearrangements in peripheral blood and to elucidate if it is associated with biochemical recurrence (BCR) in high risk (HR) and low risk (LR) patients. Methods: Radical prostatectomy (RP) was performed on 108 PCa stage pT2–pT3 patients. Preoperative vs. postoperative (one and three months) immunophenotype profile (T- and B-cell subsets, MDSC, NK, and T reg populations) was compared in peripheral blood of LR and HR groups. Results: The BCR-free survival difference was significant between the HR and LR groups. Postoperative PSA decay rate, defined as ePSA, was significantly slower in the HR group and predicted BCR at cut-off level ePSA = −2.0% d⁻¹ (AUC = 0.85 (95% CI, 0.78–0.90). Three months following tumor excision, the LR group exhibited a recovery of natural killer CD3 − CD16+ CD56+ cells, from 232 cells/µL to 317 cells/µL (p < 0.05), which was not detectable in the HR group. Prostatectomy also resulted in an increased CD8+ population in the LR group, mostly due to CD8+ CD69+ compartment (from 186 cells/µL before surgery to 196 cells/µL three months after, p < 001). The CD8+ CD69+ subset increase without total T cell increase was present in the HR group (p < 0.001). Tumor excision resulted in a myeloid-derived suppressor cell (MDSC) number increase from 12.4 cells/µL to 16.2 cells/µL in the HR group, and no change was detectable in LR patients (p = 0.12). An immune signature of postoperative recovery was more likely to occur in patients undergoing laparoscopic radical prostatectomy (LRP). Open RP (ORP) was associated with increased MDSC numbers (p = 0.002), whereas LRP was characterized by an immunity sparing profile, with no change in MDSC subset (p = 0.16). Conclusion: Tumor excision in prostate cancer patients results in two distinct patterns of immunophenotype rearrangement. The low-risk group is highly responsive, revealing postoperative restoration of T cells, NK cells, and CD8+ CD69+ numbers and the absence of suppressor MDSC increase. The high-risk group presented a limited response, accompanied by a suppressor MDSC increase and CD8+ CD69+ increase. The laparoscopic approach, unlike ORP, did not result in an MDSC increase in the postoperative period.

An Aptamer-Based Antagonist against the Receptor for Advanced Glycation End-Products (RAGE) Blocks Development of Colorectal Cancer

Tumor angiogenesis plays a crucial role in colorectal cancer development. Dysregulation of the receptor for the advanced glycation end-products (RAGE) transmembrane signaling mediates inflammation, resulting in various cancers. However, the mechanism of the RAGE signaling pathway in modulating development of colorectal cancer has not been explored. In this study, an aptamer-based RAGE antagonist (Apt-RAGE) was used to inhibit interaction between RAGE and S100B, thus blocking downstream NFκB-mediated signal transduction. In vitro results showed that Apt-RAGE effectively inhibited S100B-dependent and S100B-independent RAGE/NFκB activation in colorectal HCT116 cancer cells, thus decreasing proliferation and migration of cells. Notably, expression and secretion of VEGF-A were inhibited, implying that Apt-RAGE can be used as an antiangiogenesis agent in tumor therapy. Moreover, Apt-RAGE inhibited tumor growth and microvasculature formation in colorectal tumor-bearing mice. Inhibition of angiogenesis by Apt-RAGE was positively correlated with suppression of the RAGE/NFκB/VEGF-A signaling. The findings of this study show that Apt-RAGE antagonist is a potential therapeutic agent for treatment of colorectal cancer.