Molecular Immunotherapy: Promising Approach to Treat Metastatic Colorectal Cancer by Targeting Resistant Cancer Cells or Cancer Stem Cells

Colorectal cancer: a comprehensive review of carcinogenesis, diagnosis, and novel strategies for classified treatments

Colorectal cancer is the third most common and the second deadliest cancer worldwide. To date, colorectal cancer becomes one of the most important challenges of the health system in many countries. Since the clinical symptoms of this cancer appear in the final stages of the disease and there is a significant golden time between the formation of polyps and the onset of cancer, early diagnosis can play a significant role in reducing mortality. Today, in addition to colonoscopy, minimally invasive methods such as liquid biopsy have received much attention. The treatment of this complex disease has been mostly based on traditional treatments including surgery, radiotherapy, and chemotherapy; the high mortality rate indicates a lack of success for current treatment methods. Moreover, disease recurrence is another problem of traditional treatments. Recently, new approaches such as targeted therapy, immunotherapy, and nanomedicine have opened new doors for cancer treatment, some of which have already entered the market, and many methods have shown promising results in clinical trials. The success of immunotherapy in the treatment of refractory disease, the introduction of these methods into neoadjuvant therapy, and the successful results in tumor shrinkage without surgery have made immunotherapy a tough competitor for conventional treatments. It seems that the combination of those methods with such targeted therapies will go through promising changes in the future of colorectal cancer treatment.

Targeting the "tumor microenvironment": RNA-binding proteins in the spotlight in colorectal cancer therapy

Colorectal cancer (CRC) is the third most common cancer and has the second highest mortality rate among cancers. The development of CRC involves both genetic and epigenetic abnormalities, and recent research has focused on exploring the ex-transcriptome, particularly post-transcriptional modifications. RNA-binding proteins (RBPs) are emerging epigenetic regulators that play crucial roles in post-transcriptional events. Dysregulation of RBPs can result in aberrant expression of downstream target genes, thereby affecting the progression of colorectal tumors and the prognosis of patients. Recent studies have shown that RBPs can influence CRC pathogenesis and progression by regulating various components of the tumor microenvironment (TME). Although previous research on RBPs has primarily focused on their direct regulation of colorectal tumor development, their involvement in the remodeling of the TME has not been systematically reported. This review aims to highlight the significant role of RBPs in the intricate interactions within the CRC tumor microenvironment, including tumor immune microenvironment, inflammatory microenvironment, extracellular matrix, tumor vasculature, and CRC cancer stem cells. We also highlight several compounds under investigation for RBP-TME-based treatment of CRC, including small molecule inhibitors such as antisense oligonucleotides (ASOs), siRNAs, agonists, gene manipulation, and tumor vaccines. The insights gained from this review may lead to the development of RBP-based targeted novel therapeutic strategies aimed at modulating the TME, potentially inhibiting the progression and metastasis of CRC.

Comparing the efficacy of combined versus single immune cell adaptive therapy targeting colorectal cancer

PURPOSE

Colorectal cancer (CRC) is the most frequent cancer with limited therapeutic achievements. Recently, adoptive cellular immunotherapy has been developed as an antitumor therapy. However, its efficacy has not been tested in CRC. This study investigated the ability of an immune cell cocktail of dendritic cells (DCs), T cells, and natural killer (NK) cells to overcome immunological hurdles and improve the therapeutic efficacy of cell therapy for CRC.

METHODS

CRC lysate-pulsed monocyte-derived DCs (Mo-DCs), CRC antigen-specifically expanded T cells (CTL), and in vitro-expanded NK cells were cultured from patient peripheral blood mononuclear cells (PBMC). The ability of the combined immune cells to kill autologous tumor cells was investigated by co-culturing the combined immune cells with patient-derived tumor cells.

RESULTS

The Mo-DCs produced expressed T cell co-stimulating molecules like CD80, CD86, human leukocyte antigen (HLA)-DR and HLA-ABC, at high levels and were capable of activating naive T cells. The expanded T cells were predominantly CD8 T cells with high levels of CD8 effector memory cells and low levels of regulatory T cells. The NK cells expressed high levels of activating receptors and were capable of killing other cancer cell lines (K562 and HT29). The immune cell cocktail demonstrated a higher ability to kill autologous tumor cells than single types. An in vivo preclinical study confirmed the safety of the combined immune cell adaptive therapy showing no therapy-related death or general toxicity symptoms.

CONCLUSION

The results suggested that combined immune cell adaptive therapy could overcome the limited efficacy of cell immunotherapy.

Molecular and immunological mechanisms of clonal evolution in multiple myeloma

Multiple myeloma (MM) is a hematologic malignancy characterized by the proliferation of clonal plasma cells in the bone marrow (BM). It is known that early genetic mutations in post-germinal center B/plasma cells are the cause of myelomagenesis. The acquisition of additional chromosomal abnormalities and distinct mutations further promote the outgrowth of malignant plasma cell populations that are resistant to conventional treatments, finally resulting in relapsed and therapy-refractory terminal stages of MM. In addition, myeloma cells are supported by autocrine signaling pathways and the tumor microenvironment (TME), which consists of diverse cell types such as stromal cells, immune cells, and components of the extracellular matrix. The TME provides essential signals and stimuli that induce proliferation and/or prevent apoptosis. In particular, the molecular pathways by which MM cells interact with the TME are crucial for the development of MM. To generate successful therapies and prevent MM recurrence, a thorough understanding of the molecular mechanisms that drive MM progression and therapy resistance is essential. In this review, we summarize key mechanisms that promote myelomagenesis and drive the clonal expansion in the course of MM progression such as autocrine signaling cascades, as well as direct and indirect interactions between the TME and malignant plasma cells. In addition, we highlight drug-resistance mechanisms and emerging therapies that are currently tested in clinical trials to overcome therapy-refractory MM stages.

Efficacy of Whole Cancer Stem Cell-Based Vaccines: A Systematic Review of Preclinical and Clinical Studies

BACKGROUND

Despite the conventional cancer therapeutic, cancer treatment remains a medical challenge due to neoplasm metastasis and cancer recurrence; therefore, new approaches promoting therapeutic strategies are highly desirable. As a new therapy, the use of whole neoplastic stem cells or cancer stem cell (CSC)-based vaccines is one strategy to overcome these obstacles. We investigated the effects of whole CSC-based vaccines on the solid tumor development, metastasis, and survival rate.

METHODS

Primary electronic databases (PubMed/MEDLINE, Scopus, Embase, and Web of Science) and a major clinical registry were searched. Interventional studies of whole CSC-based vaccines in rodent cancer models (38 studies) and human cancer patients (11 studies) were included; the vaccine preparation methodologies, effects, and overall outcomes were evaluated.

RESULTS

Preclinical studies were divided into 4 groups: CSC-lysates/ inactivated-CSC-based vaccines, CSC-lysate-loaded dendritic cell (CSC-DC) vaccines, cytotoxic T-cell (CTL) vaccines generated with CSC-DC (CSC-DC-CTL), and combinatorial treatments carried out in the prophylactic and therapeutic experimental models. The majority of preclinical studies reported a promising effect on tumor growth, survival rate, and metastasis. Moreover, whole CSC-based vaccines induced several antitumor immune responses. A small number of clinical investigations suggested that the whole CSC-based vaccine treatment is beneficial; however, further research is required.

CONCLUSIONS

This comprehensive review provides an overview of the available methods for assessing the efficacy of whole CSC-based vaccines on tumor development, metastasis, and survival rate. In addition, it presents a set of recommendations for designing high-quality clinical studies that may allow to determine the efficacy of whole CSC-based-vaccines in cancer therapy.

The Immunosuppressive Effect of TNFR2 Expression in the Colorectal Cancer Microenvironment

Colorectal cancer (CRC) represents one of the most common causes of death among cancers worldwide. Its incidence has been increasing among the young population. Many risk factors contribute to the development and progression of CRC and about 70% of them are sporadic. The CRC microenvironment is highly heterogeneous and represents a very complex immunosuppressive platform. Many cytokines and their receptors are vital participants in this immunosuppressive microenvironment. Tumor necrosis factors (TNFs) and TNF receptor 2 (TNFR2) are critical players in the development of CRC. TNFR2 was observed to have increased the immunosuppressive activity of CRC cells via regulatory T cells (T regs) and myeloid-derived suppressor cells (MDSC) in the CRC microenvironment. However, the exact mechanism of TNFR2 in regulating the CRC prognosis remains elusive. Here, we discuss the role of TNFR2 in immune escape mechanism of CRC in the immunosuppressive cells, including Tregs and MDSCs, and the complex signaling pathways that facilitate the development of CRC. It is suggested that extensive studies on TNFR2 downstream signaling must be done, since TNFR2 has a high potential to be developed into a therapeutic agent and cancer biomarker in the future.

Molecular Impact of the Tumor Microenvironment on Multiple Myeloma Dissemination and Extramedullary Disease

Multiple myeloma (MM) is the most common malignant monoclonal disease of plasma cells. Aside from classical chemotherapy and glucocorticoids, proteasome inhibitors, immunomodulatory agents and monoclonal antibodies are used in the current treatment scheme of MM. The tumor microenvironment (TME) plays a fundamental role in the development and progression of numerous solid and non-solid cancer entities. In MM, the survival and expansion of malignant plasma cell clones heavily depends on various direct and indirect signaling pathways provided by the surrounding bone marrow (BM) niche. In a number of MM patients, single plasma cell clones lose their BM dependency and are capable to engraft at distant body sites or organs. The resulting condition is defined as an extramedullary myeloma (EMM). EMMs are highly aggressive disease stages linked to a dismal prognosis. Emerging literature demonstrates that the dynamic interactions between the TME and malignant plasma cells affect myeloma dissemination. In this review, we aim to summarize how the cellular and non-cellular BM compartments can promote plasma cells to exit their BM niche and metastasize to distant intra-or extramedullary locations. In addition, we list selected therapy concepts that directly target the TME with the potential to prevent myeloma spread.

Trained Immunity of IL-12-, IL-15-, and IL-18-Induced CD3+CD56+ NKT-Like Cells

CD₃+CD₅₆+ natural killer T (NKT)-like cells have an immune function of T cells and NK cells, which play an important role in antitumor and antiviral immune responses. This study aims to establish a CD₃+CD₅₆+ NKT-like cell model by simulating the memory NK effect induced by cytokines IL-12, IL-15, and IL-18 (IL-12/15/18) and explore the formation mechanism. Our study found that the IL-12/15/18 preactivated CD₃+CD₅₆+ NKT-like cells exhibited enhanced IFN-γ production in response to restimulation with IL-12/15/18 for 6h on day 7. The intrinsic potential of these trained cells was significantly improved, showing an increase in IFN-γ, TNF-α, and cell proliferation potential. The IFN-γ release, granzyme B level, and proliferation ability significantly increased when stimulated by NK-cell-sensitive K562 tumor cells. Among these cytokines, the combination of IL-12/15/18 was particularly effective. After the preactivation of IL-12/15/18, some cell surface proteins related to function and differentiation, such as CD11b, CD62 L, NKp46, NKG2A, and CD127, showed an evident and consistent change trend. The CDK4/6 inhibitor can effectively weaken this effect, and the expression of cyclin D1, Rb protein phosphorylation, and E2F-1 decreased significantly. Our work revealed that cytokine IL-12/15/18 can induce CD₃+CD₅₆+ NKT-like cells to obtain enhanced training immunity, which was a memory-like phenomenon.

LncRNAs, the Molecules Involved in Communications With Colorectal Cancer Stem Cells

Colorectal cancer stem cells (CRCSCs) can actively self-renew, as well as having multidirectional differentiation and tumor regeneration abilities. Because the high functional activities of CRCSCs are associated with low cure rates in patients with colorectal cancer, efforts have sought to determine the function and regulatory mechanisms of CRCSCs. To date, however, the potential regulatory mechanisms of CRCSCs remain incompletely understood. Many non-coding genes are involved in tumor invasion and spread through their regulation of CRCSCs, with long non-coding RNAs (lncRNAs) being important non-coding RNAs. LncRNAs may be involved in the colorectal cancer development and drug resistance through their regulation of CRCSCs. This review systematically evaluates the latest research on the ability of lncRNAs to regulate CRCSC signaling pathways and the involvement of these lncRNAs in colorectal cancer promotion and suppression. The regulatory network of lncRNAs in the CRCSC signaling pathway has been determined. Further analysis of the potential clinical applications of lncRNAs as novel clinical diagnostic and prognostic biomarkers and therapeutic targets for colorectal cancer may provide new ideas and protocols for the prevention and treatment of colorectal cancer.

Association of Angiogenesis Gene Expression With Cancer Prognosis and Immunotherapy Efficacy

Background: Several new blood vessels are formed during the process of tumor development. These new blood vessels provide nutrients and water for tumour growth, while spreading tumour cells to distant areas and forming new metastases in different parts of the body. The available evidence suggests that tumour angiogenesis is closely associated with the tumour microenvironment and is regulated by a variety of pro-angiogenic factors and/or angiogenic inhibitors.

Methods: In the present study, a comprehensive characterization of angiogenesis genes expression was performed in a pan-cancer analysis across the 33 human cancer types. Further, genetic data from several public databases were also used in the current study. An angiogenesis score was assigned to The Cancer Genome Atlas (TCGA) pan-cancer data, with one angiogenesis score as per sample for each tumour.

Results: It was found that angiogenesis genes vary across cancer types, and are associated with a number of genomic and immunological features. Further, it was noted that macrophages and iTreg infiltration were generally higher in tumours with high angiogenesis scores, whereas lymphocytes and B cells showed the opposite trend. Notably, NK cells showed significantly different correlations among cancer types. Furthermore, results of the present study showed that a high angiogenesis score was associated with poor survival and aggressive types of cancer in most of the cancer types.

Conclusion: In conclusion, the current study evidently showed that the expression of angiogenesis genes is a key feature of tumour biology that has a major impact on prognosis of patient with cancers.

Intertwined leukocyte balances in tumours and peripheral blood as robust predictors of right and left colorectal cancer survival

BACKGROUND

Colorectal cancer (CRC) accounts for 9.4% of overall cancer deaths, ranking second after lung cancer. Despite the large number of factors tested to predict their outcome, most patients with similar variables show big differences in survival. Moreover, right-sided CRC (RCRC) and left-sided CRC (LCRC) patients exhibit large differences in outcome after surgical intervention as assessed by preoperative blood leukocyte status. We hypothesised that stronger indexes than circulating (blood) leukocyte ratios to predict RCRC and LCRC patient outcomes will result from combining both circulating and infiltrated (tumour/peritumour fixed tissues) concentrations of leukocytes.

AIM

To seek variables involving leukocyte balances in peripheral blood and tumour tissues and to predict the outcome of CRC patients.

METHODS

Sixty-five patients diagnosed with colon adenocarcinoma by the Digestive Surgery Service of the La Paz University Hospital (Madrid, Spain) were enrolled in this study: 43 with RCRC and 22 with LCRC. Patients were followed-up from January 2017 to March 2021 to record overall survival (OS) and recurrence-free survival (RFS) after surgical interventions. Leukocyte concentrations in peripheral blood were determined by routine laboratory protocols. Paraffin-fixed samples of tumour and peritumoural tissues were assessed for leukocyte concentrations by immunohistochemical detection of CD4, CD8, and CD14 marker expression. Ratios of leukocyte concentration in blood and tissues were calculated and evaluated for their predictor values for OS and RFS with Spearman correlations and Cox univariate and multivariate proportional hazards regression, followed by the calculation of the receiver-operating characteristic and area under the curve (AUC) and the determination of Youden’s optimal cutoff values for those variables that significantly correlated with either RCRC or LCRC patient outcomes. RCRC patients from the cohort were randomly assigned to modelling and validation sets, and clinician-friendly nomograms were developed to predict OS and RFS from the respective significant indexes. The accuracy of the model was evaluated using calibration and validation plots.

RESULTS

The relationship of leukocyte ratios in blood and peritumour resulted in six robust predictors of worse OS in RCRC: CD8⁺ lymphocyte content in peritumour (CD8_pt, AUC = 0.585, cutoff < 8.250, P = 0.0077); total lymphocyte content in peritumour (CD4CD8_pt, AUC = 0.550, cutoff < 10.160, P = 0.0188); lymphocyte-to-monocyte ratio in peritumour (LMR_pt, AUC = 0.807, cutoff < 3.185, P = 0.0028); CD8⁺ LMR in peritumour (CD8MR_pt, AUC = 0.757, cutoff < 1.650, P = 0.0007); the ratio of blood LMR to LMR in peritumour (LMR_b/LMR_pt, AUC = 0.672, cutoff > 0.985, P = 0.0244); and the ratio of blood LMR to CD8⁺ LMR in peritumour (LMR_b/CD8MR_pt, AUC = 0.601, cutoff > 1.485, P = 0.0101). In addition, three robust predictors of worse RFS in RCRC were found: LMR_pt (AUC = 0.737, cutoff < 3.185, P = 0.0046); LMR_b/LMR_pt (AUC = 0.678, cutoff > 0.985, P = 0.0155) and LMR_b/CD8MR_pt (AUC = 0.615, cutoff > 1.485, P = 0.0141). Furthermore, the ratio of blood LMR to CD4⁺ LMR in peritumour (LMR_b/CD4MR_pt, AUC = 0.786, cutoff > 10.570, P = 0.0416) was found to robustly predict poorer OS in LCRC patients. The nomograms showed moderate accuracy in predicting OS and RFS in RCRC patients, with concordance index of 0.600 and 0.605, respectively.

CONCLUSION

Easily obtainable variables at preoperative consultation, defining the status of leukocyte balances between peripheral blood and peritumoural tissues, are robust predictors for OS and RFS of both RCRC and LCRC patients.

The Effect of Terpenoid Natural Chinese Medicine Molecular Compound on Lung Cancer Treatment

Among all malignant tumors in the whole universe, the incidence and mortality of lung cancer disease rank first. Especially in the past few years, the occurrence of lung cancer in the urban population has continued to increase, which seriously threatens the lives and health of people. Among the many treatments for lung cancer, chemotherapy is the best one, but traditional chemotherapy has low specificity and drug resistance. To address the above issue, this study reviews the five biological pathways that common terpenoid compounds in medicinal plants interfere with the occurrence and development of lung cancer: cell proliferation, cell apoptosis, cell autophagy, cell invasion, metastasis, and immune mechanism regulation. In addition, the mechanism of the terpenoid natural traditional Chinese medicine monomer compound combined with Western medicine in the multipathway antilung cancer is summarized.

Development and Validation of a TNF Family-Based Signature for Predicting Prognosis, Tumor Immune Characteristics, and Immunotherapy Response in Colorectal Cancer Patients

In this study, a comprehensive analysis of TNF family members in colorectal cancer (CRC) was conducted and a TNF family-based signature (TFS) was generated to predict prognosis and immunotherapy response. Using the expression data of 516 CRC patients from The Cancer Genome Atlas (TCGA) database, TNF family members were screened to construct a TFS by using the univariate Cox proportional hazards regression and the least absolute shrinkage and selection operator- (LASSO-) Cox proportional hazards regression method. The TFS was then validated in a meta-Gene Expression Omnibus (GEO) cohort (n = 1162) from the GEO database. Additionally, the tumor immune characteristics and predicted responses to immune checkpoint blockade in TFS-based risk subgroups were analyzed. Eight genes (TNFRSF11A, TNFRSF10C, TNFRSF10B, TNFSF11, TNFRSF25, TNFRSF19, LTBR, and NGFR) were used to construct the TFS. Compared to the high-risk patients, the low-risk patients had better overall survival, which was verified by the GEO data. In addition, a high TFS risk score was associated with high infiltration of regulatory T cells (Tregs), nonactivated macrophages (M0), natural killer cells, immune escape phenotypes, poor immunotherapy response, and tumorigenic and metastasis-related pathways. Conversely, a low TFS risk score was related to high infiltration of resting CD4 memory T cells and resting dendritic cells, few immune escape phenotypes, and high sensitivity to immunotherapy. Thus, the eight gene-based TFS is a promising index to predict the prognosis, immune characteristics, and immunotherapy response in CRC, and our results also provide new understanding of the role of the TNF family members in the prognosis and treatment of CRC.

A Genome-Scale CRISPR Knock-Out Screen Identifies MicroRNA-5197-5p as a Promising Radiosensitive Biomarker in Colorectal Cancer

Radioresistance is one of the main reasons causing unsatisfactory curative effects of ionizing radiation (IR) against colorectal cancer (CRC). However, its underlying mechanisms remain unclear yet. In the present study, we applied a genome-scale CRISPR knockout screen in combination of NGS sequencing upon CRC cell lines to explore regulatory factors involved radioresistance of CRC, and 3 candidate genes were identified. Cytotoxicity of IR was determined by Cell Counting Kit-8 (CCK-8) assay, colony formation assay and apoptosis assay, and microRNA-5197-5p (miR-5197) was found to significantly enhance the cytotoxicity of IR to CRC cells. By further mechanistic investigation, we demonstrated that miR-5197 directly targeted CDK6 and inhibited its expression in RKO cells, which induced cell cycle arrest at G1/S phase and inhibited cell division, thereby radiosensitivity was enhanced by miR-5197. Our findings revealed that miR-5197 might be a critical factor regulating CRC cell radiosensitivity and provided novel insights into the development of therapeutic strategies for CRC patients who are resistant to IR.

Epigenetic regulation of autophagy: A key modification in cancer cells and cancer stem cells

Aberrant epigenetic alterations play a decisive role in cancer initiation and propagation via the regulation of key tumor suppressor genes and oncogenes or by modulation of essential signaling pathways. Autophagy is a highly regulated mechanism required for the recycling and degradation of surplus and damaged cytoplasmic constituents in a lysosome dependent manner. In cancer, autophagy has a divergent role. For instance, autophagy elicits tumor promoting functions by facilitating metabolic adaption and plasticity in cancer stem cells (CSCs) and cancer cells. Moreover, autophagy exerts pro-survival mechanisms to these cancerous cells by influencing survival, dormancy, immunosurveillance, invasion, metastasis, and resistance to anti-cancer therapies. In addition, recent studies have demonstrated that various tumor suppressor genes and oncogenes involved in autophagy, are tightly regulated via different epigenetic modifications, such as DNA methylation, histone modifications and non-coding RNAs. The impact of epigenetic regulation of autophagy in cancer cells and CSCs is not well-understood. Therefore, uncovering the complex mechanism of epigenetic regulation of autophagy provides an opportunity to improve and discover novel cancer therapeutics. Subsequently, this would aid in improving clinical outcome for cancer patients. In this review, we provide a comprehensive overview of the existing knowledge available on epigenetic regulation of autophagy and its importance in the maintenance and homeostasis of CSCs and cancer cells.

Exploration of novel heterofused 1,2,4-triazine derivative in colorectal cancer

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in men and in women. The impact of the new pyrazolo[4,3-e]tetrazolo[1,5-b][1,2,4]triazine sulphonamide (MM-129) was evaluated against human colon cancer in vitro and in zebrafish xenografts. Our results show that this new synthesised compound effectively inhibits cell survival in BTK-dependent mechanism. Its effectiveness is much higher at a relatively low concentration as compared with the standard chemotherapy used for CRC, i.e. 5-fluorouracil (5-FU). Flow cytometry analysis after annexin V-FITC and propidium iodide staining revealed that apoptosis was the main response of CRC cells to MM-129 treatment. We also found that MM-129 effectively inhibits tumour development in zebrafish embryo xenograft model, where it showed a markedly synergistic anticancer effect when used in combination with 5-FU. The above results suggest that this novel heterofused 1,2,4-triazine derivative may be a promising candidate for further evaluation as chemotherapeutic agent against CRC.

Epigenetic Silencing of Immune-Checkpoint Receptors in Bone Marrow- Infiltrating T Cells in Acute Myeloid Leukemia

Background

Immune-checkpoint (IC) inhibitors have revolutionized the treatment of multiple solid tumors and defined lymphomas, but they are largely ineffective in acute myeloid leukemia (AML). The reason why especially PD1/PD-L1 blocking agents are not efficacious is not well-understood but it may be due to the contribution of different IC ligand/receptor interactions that determine the function of T cells in AML.

Methods

To analyze the interactions of IC ligands and receptors in AML, we performed a comprehensive transcriptomic analysis of FACS-purified leukemia stem/progenitor cells and paired bone marrow (BM)-infiltrating CD4⁺ and CD8⁺ T cells from 30 patients with AML. The gene expression profiles of activating and inhibiting IC ligands and receptors were correlated with the clinical data. Epigenetic mechanisms were studied by inhibiting the histone deacetylase with valproic acid or by gene silencing of PAC1.

Results

We observed that IC ligands and receptors were mainly upregulated in leukemia stem cells. The gene expression of activating IC ligands and receptors correlated with improved prognosis and vice versa. In contrast, the majority of IC receptor genes were downregulated in BM-infiltrating CD8⁺ T cells and partially in CD4⁺ T cells, due to pathological chromatin remodeling via histone deacetylation. Therefore, treatment with histone deacetylase inhibitor (HDACi) or silencing of PAC1, as a T cell-specific epigenetic modulator, significantly increased the expression of IC receptors and defined effector molecules in CD8⁺ T cells.

Conclusions

Our results suggest that CD8⁺ T cells in AML are dysfunctional mainly due to pathological epigenetic silencing of activating IC receptors rather than due to signaling by immune inhibitory IC receptors, which may explain the limited efficacy of antibodies that block immune-inhibitory ICs in AML.

A Prognostic Model Based on the Immune-Related lncRNAs in Colorectal Cancer

Background

Colorectal cancer (CRC) is one of the most common malignant tumors with a poor prognosis. At present, the pathogenesis is not completely clear. Therefore, finding reliable prognostic indicators for CRC is of important clinical significance. In this study, bioinformatics methods were used to screen the prognostic immune-related lncRNAs of CRC, and a prognostic risk scoring model based on immune-related lncRNAs signatures were constructed to provide a basis for prognostic evaluation and immunotherapy of CRC patients.

Methods

The clinical information and RNA-seq data of CRC patients were obtained from The Cancer Genome Atlas (TCGA) database. The information of immune-related lncRNA was downloaded from the immunology database and analysis portal. The differentially expressed immune-related lncRNAs (IRLs) were screened by the edgeR package of R software. The prognostic value of IRLs was studied. Based on Cox regression analysis, a prognostic index (IRLPI) based on IRLs was established, and the relationship between the risk score and the clinicopathological characteristics of CRC was analyzed to determine the effectiveness of the risk score model as an independent prognostic factor.

Results

A total of 240 differentially expressed IRLs were identified between normal colorectal cancer tissues and normal colorectal cancer tissues, in which 8 were significantly associated with the survival of CRC patients (P < 0.05), including LINC00461, LINC01055, ELFN1-AS1, LMO7-AS1, CYP4A22-AS1, AC079612.1, LINC01351, and MIR31HG. And most of the lncRNAs related to survival were risk factors for the prognosis of CRC. The index established based on the 7 survival-related IRLs found to be highly accurate in monitoring CRC prognosis. Besides, IRLPI was significantly correlated with a variety of pathological factors and immune cell infiltration.

Conclusion

Eight immune-related lncRNAs closely related to the prognosis of CRC patients were identified from the TCGA database. At the same time, an independent IRLPI was constructed, which may be helpful for clinicians to assess the prognosis of patients with CRC and to formulate individualized treatment plans.

Roles of microRNAs in Gastrointestinal Cancer Stem Cell Resistance and Therapeutic Development

Resistance to cancer treatment is one of the major challenges currently faced when treating gastrointestinal (GI) cancers. A major contributing factor to this resistance is the presence of cancer stem cells (CSCs) in GI cancers (e.g., colorectal, pancreatic, gastric, liver cancer). Non-coding RNAs, such as microRNAs (miRNAs), have been found to regulate several key targets that are responsible for cancer stemness, and function as oncogenic miRNAs (oncomiRs) or tumor suppressor miRNAs. As a result, several miRNAs have been found to alter, or be altered by, the expression of CSC-defining markers and their related pathways. These miRNAs can be utilized to affect stemness in multiple ways, including directly targeting CSCs and enhancing the efficacy of cancer therapeutics. This review highlights current studies regarding the roles of miRNAs in GI CSCs, and efforts towards the development of cancer therapeutics.

BTF3 promotes stemness and inhibits TypeⅠInterferon signaling pathway in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a major challenge in clinical practice due to its aggressiveness and lack of targeted treatment. Cancer stem-like traits contribute to tumorigenesis and immune privilege of TNBC. However, the relationship of stemness and immunosurveillance remains unclear. Here, we demonstrate that BTF3 expression is related with stem-like properties in TNBC cells. BTF3 modulates stemness, migration and proliferation of TNBC in vitro. Bioinformatics analysis revealed that interferon signaling pathways and IRF7, both of which participate in the immune escape of TNBC, are closely related to BTF3 in TNBC cells. Knockdown of BTF3 activates IRF7 expression through increased degradation of BMI1, a protein that can represses IRF7 transcription by directly binding to its promotor region. BTF3 links stem-like traits and the interferon signaling pathway, revealing the potential connection of stemness and immunomodulation in TNBC. Clinically, we suggest that BTF3 is predictive of poor prognosis in patients with TNBC. Together, our findings highlight an important role of BTF3 in regulating the progression of TNBC cells.