Cross-Talk Between Tumor Cells Undergoing Epithelial to Mesenchymal Transition and Natural Killer Cells in Tumor Microenvironment in Colorectal Cancer

The Impact of Laparoscopic Appendectomy and Open Appendectomy on B7-H3-Mediated Intrinsic Immune Response in Children with Acute Suppurative Appendicitis

Purpose

Surgery impairs immune function and increases postoperative complications. B7H3, a co-stimulatory molecule, plays a crucial role in immune regulation. The present study examined the impact of B7H3 on the postoperative immune response in children with acute suppurative appendicitis (ASA) by comparing preoperative and postoperative B7H3 levels in laparoscopic surgery (LA) and open appendectomy (OA).

Patients and Methods

198 pediatric ASA patients were enrolled. The researcher group performed LA, while the control group performed OA. Perioperative time, recovery time of gastrointestinal function, time to pass gas, length of incision, and length of hospitalization were compared in the perioperative period. Additionally, an ELISA assay was conducted to examine the levels of inflammatory factors and B7H3 and CD28. Short-term postoperative complications were also evaluated.

Results

Compared with the control group, the research group had a short operative time, gastrointestinal function recovery time, gas time, and hospitalization time. The short-term complication rate was significantly lower in the research group. More importantly, B7H3 and CD28 were insignificantly different preoperatively, but they were all reduced postoperatively. Moreover, the reduction was more pronounced in the research group. The same results were noted in inflammatory factors and immune markers, which were non-significant different preoperatively and were typically reduced postoperatively, particularly in the research group. Finally, postoperative B7H3 was positively correlated with both inflammatory factors and immune cell levels.

Conclusion

B7H3 was reduced in both postoperative periods, and the reduction was more pronounced in the LA group. B7H3 may be involved in postoperative recovery by modulating postoperative inflammation and immune responses.

Contribution of Autophagy to Epithelial Mesenchymal Transition Induction during Cancer Progression

Epithelial Mesenchymal Transition (EMT) is a dedifferentiation process implicated in many physio-pathological conditions including tumor transformation. EMT is regulated by several extracellular mediators and under certain conditions it can be reversible. Autophagy is a conserved catabolic process in which intracellular components such as protein/DNA aggregates and abnormal organelles are degraded in specific lysosomes. In cancer, autophagy plays a controversial role, acting in different conditions as both a tumor suppressor and a tumor-promoting mechanism. Experimental evidence shows that deep interrelations exist between EMT and autophagy-related pathways. Although this interplay has already been analyzed in previous studies, understanding mechanisms and the translational implications of autophagy/EMT need further study. The role of autophagy in EMT is not limited to morphological changes, but activation of autophagy could be important to DNA repair/damage system, cell adhesion molecules, and cell proliferation and differentiation processes. Based on this, both autophagy and EMT and related pathways are now considered as targets for cancer therapy. In this review article, the contribution of autophagy to EMT and progression of cancer is discussed. This article also describes the multiple connections between EMT and autophagy and their implication in cancer treatment.

Methylenetetrahydrofolate reductase polymorphic variants C677T and A1298C in rectal cancer in Slavic population: significance for cancer risk and response to chemoradiotherapy

Background: Methylenetetrahydrofolate reductase (MTHFR) single nucleotide polymorphisms (SNPs) have been suggested as risk, prognostic, and predictive factors for colorectal cancer in various populations, but have not been validated so far. The aim of this study was to examine the association of MTHFR C677T (rs1801133) and A1298C (rs1801131) single nucleotide polymorphisms with the risk of rectal cancer as well as the response to neoadjuvant chemoradiotherapy (nCRT) based on 5-Fluorouracil (5-FU)/leucovorin (LV) in the locally advanced setting. Patients and methods: This case-control study included 119 healthy controls and 97 patients with locally advanced rectal cancer (LARC). For MTHFR genotyping, restriction fragment length polymorphism analysis (PCR-RFLP) was employed. Results: In silico analysis highlighted that SNPs C677T and A1298T correlate with MTHFR gene expression, and that gene expression profile correlates with cancer risk and stage. Using dominant and recessive models, it was found that the MTHFR 677CC vs. 677CT+677TT have increased risk of cancer development (odds ratio (OR): 2.27; 95% confidence interval (CI): 1.30-3.95, p = 0.002) as well as 677CC+677CT compared to 677TT (OR: 4.18, 95% CI: 1.16-14.99, p = 0.014). MTHFR 1298AA also shown increased risk for cancer development compared to 1298AC+1298CC (OR:2.0, 95% CI: 1.20-3.59, p = 0.035) Statistical analysis of combined genotypes highlighted the protective role of CT/AC combined genotype (OR: 3.15 95% CI: 1.576-6.279, p = 0.002) while the CC/AA genotype showed an increased risk for rectal cancer development (OR: 2.499, 95% CI: 1.246-5.081, p = 0.016) The carriers of the 677C/1298A haplotype had the highest risk for developing rectal cancer (OR: 1.74; 95% CI: 1.198-2.530, p = 0.002) while the 677T/1298C haplotype seems to provide a protective effect. (OR: 0.44; 95%CI 0.248-0.795, p = 0.003). No significant association with response to chemoradiotherapy was found. Conclusion: Our data point to MTHFR 667C allele and 1298A alleles as low-penetrance risk factors for rectal cancer in our population. To the best of our knowledge, this is the first study of this type performed on the Slavic population in the Western Balkan, as various population-based factors might also be significant our findings can be used for future meta-analyses and the construction of genetic cancer risk prediction panels.

Role of Histone Deacetylase 6 and Histone Deacetylase 6 Inhibition in Colorectal Cancer

Histone deacetylase 6 (HDAC6), by deacetylation of multiple substrates and association with interacting proteins, regulates many physiological processes that are involved in cancer development and invasiveness such as cell proliferation, apoptosis, motility, epithelial to mesenchymal transition, and angiogenesis. Due to its ability to remove misfolded proteins, induce autophagy, and regulate unfolded protein response, HDAC6 plays a protective role in responses to stress and enables tumor cell survival. The scope of this review is to discuss the roles of HDCA6 and its implications for the therapy of colorectal cancer (CRC). As HDAC6 is overexpressed in CRC, correlates with poor disease prognosis, and is not essential for normal mammalian development, it represents a good therapeutic target. Selective inhibition of HDAC6 impairs growth and progression without inducing major adverse events in experimental animals. In CRC, HDAC6 inhibitors have shown the potential to reduce tumor progression and enhance the therapeutic effect of other drugs. As HDAC6 is involved in the regulation of immune responses, HDAC6 inhibitors have shown the potential to improve antitumor immunity by increasing the immunogenicity of tumor cells, augmenting immune cell activity, and alleviating immunosuppression in the tumor microenvironment. Therefore, HDAC6 inhibitors may represent promising candidates to improve the effect of and overcome resistance to immunotherapy.

Biomarkers in Adult-Type Diffuse Gliomas: Elevated Levels of Circulating Vesicular Heat Shock Protein 70 Serve as a Biomarker in Grade 4 Glioblastoma and Increase NK Cell Frequencies in Grade 3 Glioma

The presence of circulating Hsp70 levels and their influence on the immunophenotype of circulating lymphocyte subsets were examined as diagnostic/prognostic biomarkers for the overall survival (OS) in patients with IDH-mutant WHO grade 3 oligodendroglioma, astrocytoma, and IDH-wildtype grade 4 glioblastoma (GBM). Vesicular and free Hsp70 in the plasma/serum was measured using the Hsp70-exo and R&D Systems DuoSet® Hsp70 ELISAs. The immunophenotype and membrane Hsp70 status was determined by multiparameter flow cytometry on peripheral blood lymphocytes and single-cell suspensions of tumor specimens and cultured cells. Compared to healthy controls, circulating vesicular Hsp70 levels were significantly increased in patients with GBM, concomitant with a significant decrease in the proportion of CD3+/CD4+ helper T cells, whereas the frequency of NK cells was most prominently increased in patients with grade 3 gliomas. Elevated circulating Hsp70 levels and a higher prevalence of activated CD3-/CD56+/CD94+/CD69+ NK cells were associated with an improved OS in grade 3 gliomas, whereas high Hsp70 levels and low CD3+/CD4+ frequencies were associated with an adverse OS in GBM. It is assumed that a reduced membrane Hsp70 density on grade 4 versus grade 3 primary glioma cells and reduced CD3+/CD4+ T cell counts in GBM might drive an immunosuppressive tumor microenvironment.

Natural killer cell-related prognosis signature predicts immune response in colon cancer patients

Background: Natural killer (NK) cells are crucial components of the innate immune system that fight tumors and viral infections. Patients with colorectal cancer (CRC) have a poor prognosis, and immunotherapeutic tools play a key role in the treatment of CRC. Methods: Public data on CRC patients was collected from the TCGA and the GEO databases. Tissue data of CRC patients were collected from Guangxi Medical University Affiliated Cancer Hospital. An NK-related prognostic model was developed by the least absolute shrinkage and selection operator (LASSO) and Cox regression method. Validation data were collected from different clinical subgroups and an external independent validation cohort to verify the model's accuracy. In addition, multiple external independent immunotherapy datasets were collected to further examine the value of NK-related risk scores (NKRS) in the prediction of immunotherapy response. Potential biological functions of key genes were examined by methods of cell proliferation, apoptosis and Western blotting. Results: A novel prognostic model for CRC patients based on NK-related genes was developed and NKRS was generated. There was a significantly poorer prognosis among the high-NKRS group. Based on immune response prediction, patients with low NKRS may be more suitable for immunotherapy and they are more sensitive to immunotherapy. The proliferation rate of CRC cells was significantly reduced and apoptosis of CRC cells was increased after SLC2A3 was knocked down. SLC2A3 was also found to be associated with the TGF-β signaling pathway. Conclusion: NKRS has potential applications for predicting prognostic status and response to immunotherapy in CRC patients. SLC2A3 has potential as a therapeutic target for CRC.

Data-Independent Acquisition Mass Spectrometry Analysis of FFPE Rectal Cancer Samples Offers In-Depth Proteomics Characterization of the Response to Neoadjuvant Chemoradiotherapy

Locally advanced rectal cancer (LARC) presents a challenge in identifying molecular markers linked to the response to neoadjuvant chemoradiotherapy (nCRT). This study aimed to utilize a sensitive proteomic method, data-independent mass spectrometry (DIA-MS), to extensively analyze the LARC proteome, seeking individuals with favorable initial responses suitable for a watch-and-wait approach. This research addresses the unmet need to understand the response to treatment, potentially guiding personalized strategies for LARC patients. Post-treatment assessment included MRI scans and proctoscopy. This research involved 97 LARC patients treated with intense chemoradiotherapy, comprising radiation and chemotherapy. Out of 97 LARC included in this study, we selected 20 samples with the most different responses to nCRT for proteome profiling (responders vs. non-responders). This proteomic approach shows extensive proteome coverage in LARC samples. The analysis identified a significant number of proteins compared to a prior study. A total of 915 proteins exhibited differential expression between the two groups, with certain signaling pathways associated with response mechanisms, while top candidates had good predictive potential. Proteins encoded by genes SMPDL3A, PCTP, LGMN, SYNJ2, NHLRC3, GLB1, and RAB43 showed high predictive potential of unfavorable treatment outcome, while RPA2, SARNP, PCBP2, SF3B2, HNRNPF, RBBP4, MAGOHB, DUT, ERG28, and BUB3 were good predictive biomarkers of favorable treatment outcome. The identified proteins and related biological processes provide promising insights that could enhance the management and care of LARC patients.

Exploring novel genetic and hematological predictors of response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer

Introduction: The standard treatment for locally advanced rectal cancer (LARC) is neoadjuvant chemoradiotherapy (nCRT). To select patients who would benefit the most from nCRT, there is a need for predictive biomarkers. The aim of this study was to evaluate the role of clinical, pathological, radiological, inflammation-related genetic, and hematological parameters in the prediction of post-nCRT response. Materials and methods: In silico analysis of published transcriptomics datasets was conducted to identify candidate genes, whose expression will be measured using quantitative Real Time PCR (qRT-PCR) in pretreatment formaline-fixed paraffin-embedded (FFPE) samples. In this study, 75 patients with LARC were prospectively included between June 2020-January 2022. Patients were assessed for tumor response in week 8 post-nCRT with pelvic MRI scan and rigid proctoscopy. For patients with a clinical complete response (cCR) and initially distant located tumor no immediate surgery was suggested ("watch and wait" approach). The response after surgery was assessed using histopathological tumor regression grading (TRG) categories from postoperative specimens by Mandard. Responders (R) were defined as patients with cCR without operative treatment, and those with TRG 1 and TRG 2 postoperative categories. Non-responders (NR) were patients classified as TRG 3-5. Results: Responders group comprised 35 patients (46.6%) and NR group 53.4% of patients. Analysis of published transcriptomics data identified genes that could predict response to treatment and their significance was assessed in our cohort by qRT-PCR. When comparison was made in the subgroup of patients who were operated (TRG1 vs. TRG4), the expression of IDO1 was significantly deregulated (p < 0.05). Among hematological parameters between R and NR a significant difference in the response was detected for neutrophil-to-monocyte ratio (NMR), initial basophil, eosinophil and monocyte counts (p < 0.01). According to MRI findings, non-responders more often presented with extramural vascular invasion (p < 0.05). Conclusion: Based on logistic regression model, factors associated with favorable response to nCRT were tumor morphology and hematological parameters which can be easily and routinely derived from initial laboratory results (NMR, eosinophil, basophil and monocyte counts) in a minimally invasive manner. Using various metrics, an aggregated score of the initial eosinophil, basophil, and monocyte counts demonstrated the best predictive performance.

Newly identified form of phenotypic plasticity of cancer: immunogenic mimicry

Cancer plasticity is now a recognized new hallmark of cancer which is due to disturbances of cell differentiation programs. It is manifested not only in various forms like the best-known epithelial-mesenchymal transition (EMT) but also in vasculogenic and megakaryocytic mimicries regulated by EMT-specific or less-specific transcription factors such as HIF1a or STAT1/2. Studies in the past decades provided ample data that cancer plasticity can be manifested also in the expression of a vast array of immune cell genes; best-known examples are PDL1/CD274, CD47, or IDO, and we termed it immunogenic mimicry (IGM). However, unlike other types of plasticities which are epigenetically regulated, expression of IGM genes are frequently due to gene amplifications. It is important that the majority of the IGM genes are regulated by interferons (IFNs) suggesting that their protein expressions are regulated by the immune microenvironment. Most of the IGM genes have been shown to be involved in immune escape of cancers broadening the repertoire of these mechanisms and offering novel targets for immunotherapeutics.

circCAPRIN1 interacts with STAT2 to promote tumor progression and lipid synthesis via upregulating ACC1 expression in colorectal cancer

BACKGROUND

Circular RNAs (circRNAs) generated by back-splicing of precursor mRNAs (pre-mRNAs) are often aberrantly expressed in cancer cells. Accumulating evidence has revealed that circRNAs play a critical role in the progression of several cancers, including colorectal cancer (CRC). However, the current understandings of the emerging functions of circRNAs in CRC lipid metabolism and the underlying molecular mechanisms are still limited. Here, we aimed to explore the role of circCAPRIN1 in regulating CRC lipid metabolism and tumorigenesis.

METHODS

circRNA microarray was performed with three pairs of tumor and non-tumor tissues from CRC patients. The expression of circRNAs were determined by quantitative PCR (qPCR) and in situ hybridization (ISH). The endogenous levels of circRNAs in CRC cells were manipulated by transfection with lentiviruses overexpressing or silencing circRNAs. The regulatory roles of circRNAs in the occurrence of CRC were investigated both in vitro and in vivo using gene expression array, RNA pull-down/mass spectrometry, RNA immunoprecipitation assay, luciferase reporter assay, chromatin immunoprecipitation analysis, and fluorescence in situ hybridization (FISH).

RESULTS

Among circRNAs, circCAPRIN1 was most significantly upregulated in CRC tissue specimens. circCAPRIN1 expression was positively correlated with the clinical stage and unfavorable prognosis of CRC patients. Downregulation of circCAPRIN1 suppressed proliferation, migration, and epithelial-mesenchymal transition of CRC cells, while circCAPRIN1 overexpression had opposite effects. RNA sequencing and gene ontology analysis indicated that circCAPRIN1 upregulated the expressions of genes involved in CRC lipid metabolism. Moreover, circCAPRIN1 promoted lipid synthesis by enhancing Acetyl-CoA carboxylase 1 (ACC1) expression. Further mechanistic assays demonstrated that circCAPRIN1 directly bound signal transducer and activator of transcription 2 (STAT2) to activate ACC1 transcription, thus regulating lipid metabolism and facilitating CRC tumorigenesis.

CONCLUSIONS

These findings revealed the oncogenic role and mechanism of circCAPRIN1 in CRC. circCAPRIN1 interacted with STAT2 to promote CRC tumor progression and lipid synthesis by enhancing the expression of ACC1. circCAPRIN1 may be considered as a novel potential diagnostic and therapeutic target for CRC patients.

β1-Integrin plays a major role in resveratrol-mediated anti-invasion effects in the CRC microenvironment

Background: Tumor microenvironment (TME) is one of the most important factors in tumor aggressiveness, with an active exchange between tumor and other TME-associated cells that promotes metastasis. The tumor-inhibitory effect of resveratrol on colorectal cancer (CRC) cells has been frequently reported. However, whether resveratrol can specifically suppress TME-induced CRC invasion via β1-integrin receptors has not been fully elucidated yet.

Methods: Two CRC cell lines (HCT116, RKO) were cultured in multicellular, pro-inflammatory 3D-alginate TME cultures (containing fibroblasts, T-lymphocytes) to investigate the role of β1-integrin receptors in the anti-invasive and anti-metastatic effect of resveratrol by antisense oligonucleotides (ASO).

Results: Our results show that resveratrol dose-dependently suppressed the migration-promoting adhesion adapter protein paxillin and simultaneously enhanced the expression of E-cadherin associated with the phenotype change of CRC cells, and their invasion. Moreover, resveratrol blocked TME-induced phosphorylation and nuclear translocation of p65-NF-κB, which was associated with changes in the expression pattern of epithelial-mesenchymal-transition-related biomarkers (slug, vimentin, E-cadherin), metastasis-related factors (CXCR4, MMP-9, FAK), and apoptosis (caspase-3). Finally, transient transfection of β1-integrin, in contrast to knockdown of NF-κB, abrogated most anti-invasive, anti-metastatic effects as well as downstream signaling of resveratrol, resulting in a concomitant increase in CRC cell invasion, indicating a central role of β1-integrin receptors in the anti-invasive function of resveratrol.

Conclusion: These results demonstrate for the first time that silencing β1-integrins may suppress, at least in part the inhibitory effects of resveratrol on invasion and migration of CRC cells, underscoring the crucial homeostatic role of β1-integrin receptors.

The Role of Inflammatory Cytokines in the Pathogenesis of Colorectal Carcinoma—Recent Findings and Review

The inflammatory process plays a significant role in the development of colon cancer (CRC). Intestinal cytokine networks are critical mediators of tissue homeostasis and inflammation but also impact carcinogenesis at all stages of the disease. Recent studies suggest that inflammation is of greater importance in the serrated pathway than in the adenoma-carcinoma pathway. Interleukins have gained the most attention due to their potential role in CRC pathogenesis and promising results of clinical trials. Malignant transformation is associated with the pro-tumorigenic and anti-tumorigenic cytokines. The harmony between proinflammatory and anti-inflammatory factors is crucial to maintaining homeostasis. Immune cells in the tumor microenvironment modulate immune sensitivity and facilitate cancer escape from immune surveillance. Therefore, clarifying the role of underlying cytokine pathways and the effects of their modulation may be an important step to improve the effectiveness of cancer immunotherapy.

CAR T Cells Targeting Membrane-Bound Hsp70 on Tumor Cells Mimic Hsp70-Primed NK Cells

Strategies to boost anti-tumor immunity are urgently needed to treat therapy-resistant late-stage cancers, including colorectal cancers (CRCs). Cytokine stimulation and genetic modifications with chimeric antigen receptors (CAR) represent promising strategies to more specifically redirect anti-tumor activities of effector cells like natural killer (NK) and T cells. However, these approaches are critically dependent on tumor-specific antigens while circumventing the suppressive power of the solid tumor microenvironment and avoiding off-tumor toxicities. Previously, we have shown that the stress-inducible heat shock protein 70 (Hsp70) is frequently and specifically expressed on the cell surface of many different, highly aggressive tumors but not normal tissues. We could take advantage of tumors expressing Hsp70 on their membrane (‘mHsp70’) to attract and engage NK cells after in vitro stimulation with the 14-mer Hsp70 peptide TKDNNLLGRFELSG (TKD) plus low dose interleukin (IL)-2. However, a potential limitation of activated primary NK cells after adoptive transfer is their comparably short life span. T cells are typically long-lived but do not recognize mHsp70 on tumor cells, even after stimulation with TKD/IL-2. To combine the advantages of mHsp70-specificity with longevity, we constructed a CAR having specificity for mHsp70 and retrovirally transduced it into primary T cells. Co-culture of anti-Hsp70 CAR-transduced T cells with mHsp70-positive tumor cells stimulates their functional responsiveness. Herein, we demonstrated that human CRCs with a high mHsp70 expression similarly attract TKD/IL-2 stimulated NK cells and anti-Hsp70 CAR T cells, triggering the release of their lytic effector protein granzyme B (GrB) and the pro-inflammatory cytokine interferon (IFN)-γ, after 4 and 24 hours, respectively. In sum, stimulated NK cells and anti-Hsp70 CAR T cells demonstrated comparable anti-tumor effects, albeit with somewhat differing kinetics. These findings, together with the fact that mHsp70 is expressed on a large variety of different cancer entities, highlight the potential of TKD/IL-2 pre-stimulated NK, as well as anti-Hsp70 CAR T cells to provide a promising direction in the field of targeted, cell-based immunotherapies which can address significant unmet clinical needs in a wide range of cancer settings.

MS: Wip1 suppresses angiogenesis through the STAT3-VEGF signalling pathway in serous ovarian cancer

Multifaceted functions of the so-called “oncogene” Wip1 have been reported in a previous study, while its actual role remains to be explored in serous ovarian cancer (SOC). In this study, by performing bioinformatic analysis with a public database and immunohistochemical staining of Wip1 in tumour tissue from SOC, we concluded that decreased expression of Wip1 was associated with a higher rate of tumour metastasis and platinum-based therapy resistance and increased ascites volume, which led to poorer prognosis in SOC patients. We also found that overexpression of Wip1 in SKOV3 cells decreased the levels of several cytokines, including VEGF, by secretome profiling analysis, and Wip1 overexpression suppressed angiogenesis both in vitro and in vivo. Mechanistic studies indicated that overexpression of Wip1 decreased the expression of VEGF at both the protein and mRNA levels and that the inhibitory effect was mediated by dephosphorylation of STAT3 at Ser727. Our study uncovered the role of Wip1 in SOC and provides a novel therapeutic strategy for suppressing angiogenesis.