Tumorigenic Role Research Articles

Abstract 5652: A novel anti apoptotic function of CTLA4 in melanoma

Abstract Cytotoxic T Lymphocyte Antigen 4 (CTLA4) is an important immune checkpoint protein and has been utilized as an immunotherapeutic target against melanoma. Our previous studies have shown that CTLA4 is expressed at low levels in primary human melanocytes but is upregulated in mutant-BRAF/NRAS melanoma cells and tissues. Despite predominantly intracellular localization of CTLA4, its intracellular function remains highly contradictory and unsubstantiated. We found that ectopic expression of Ctla4 in mouse melanoma cell lines substantially promoted lung colonization in allograft model systems in syngeneic mice. Moreover, similar results were observed in immunocompromised recipient mice, suggesting an intracellular cell-autonomous tumorigenic role of Ctla4 in melanoma. These finding led us to investigated intracellular functions of CTLA4 and its potential roles in melanomagenesis. Through the Ingenuity Pathway Analysis of our proteomics data, we found apoptosis as a major affected pathway in Ctla4-expressing mouse melanoma cells. We treated the cells (B2905-Ctla4-ee and EV control) with doxorubicin to induce apoptosis, followed by assessment by Annexin V assay. We found that Ctla4 expressing mouse melanoma cells were significantly resistant to doxorubicin-induced apoptosis. In reciprocal experiment, we generated (by CRISPR-Cas9) CTLA4-knockout A2058 human melanoma cells that exhibit high endogenous CTLA4 expression and we found that knockout cells showed significantly increased apoptosis than the parental cells. Moreover, we also observed significant upregulation of anti-apoptotic proteins (Bnip3, Birc6, Pak1, Mcl-1, Survivin, Rac1/Cdc42, Bcl-2, and Bnip3l) and downregulation of pro-apoptotic proteins (p53 and Bad) in CTLA4-expressing human melanoma cell lines. CTLA4-expressing cells also showed significantly higher invasion in Matrigel-coated transwell assay. These findings lead us to conclude that CTLA4 plays a significant role in regulating apoptosis and promoting melanoma progression in BRAF/NRAS mutant cells. Citation Format: Hasan Raza Kazmi, Xuan Mo, Bo Zhou, Sara Preston-Alp, Scott Gross, Hassaan Wajeeh, Carmen Merali, Jonathan Soboloff, Salim Merali, M. Raza Zaidi. A novel anti apoptotic function of CTLA4 in melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5652.

Abstract 6311: Clinical assessment of DPEP1 expression and its interacting genes in tumor (T) and adjacent normal tissue (NAT) of colorectal cancer

Abstract Colorectal cancer (CRC) is one of the deadliest cancers worldwide with an estimated global rise of 60% cases by 2030. Over the last decade, advances in surgical-, chemo-, targeted-, and immuno- therapies have significantly improved survival rates, but novel biomarkers are required for the design of better screening and therapeutic strategies for CRC patients. The tumor (T) and adjacent normal tissue (NAT) can capture tumor heterogeneity and assist in the molecular classification of the tumors. In this study, we explored the clinical and molecular features of Dipeptidase (DPEP1)-related gene expression in CRC. DPEP1 is an enzyme involved in the conversion of leukotrienes and functions as an adhesive receptor for neutrophil recruitment in inflamed tissue. Primary analysis using the TCGA (The Cancer Genome Atlas) dataset identified survival and tumorigenic role of DPEP1-related gene network in COAD (colon adenocarcinoma) dataset. Higher expression of DPEP1-interacting genes (KIF1BP, GGT5, GGT1, DPEP2, and DPEP3) was found to be associated with worse overall and progression-free survival (log-rank p-value <0.01). To further characterize the distribution of the DPEP1 as a hub gene, we quantified its expression in the Augusta University cohort (40 patients, 80 T/NAT pairs). FFPE (Formalin-fixed paraffin-embedded) blocks were sectioned to extract tissue sections and were subsequently stained using H&E (Hematoxylin and eosin dyes) to identify the tumor and normal regions. Total RNA was isolated from the tumor-rich and adjacent normal regions separately post macrodissection. The mRNA molecules were quantified using a medium throughput NanoString platform. The expression of DPEP1 was found to be significantly higher (2.5-fold) in tumor-rich regions compared to adjacent normal. A similar trend of higher expression in tumors was observed in the orthologous TCGA-COAD dataset. Immune cell infiltration analysis identified a positive correlation between DPEP1 expression and M2 macrophages (p-value <0.01). Generally, the M2 subtype of macrophages has been known to exhibit immunosuppressive and pro-tumor properties. Additional gene set enrichment analysis identified an inverse association between DPEP1 expression and the Interferon-gamma signaling pathway (NES = -2.4, p-value <0.01). In conclusion, higher expression of DPEP1-related gene expression has a prognostic influence on CRC. Its positive association with M2 macrophages and negative association with anti-tumor cytokines forms a distinct subtype of CRC tumor that can benefit from emerging immunotherapies. Citation Format: Pankaj Ahluwalia, Ashis K. Mondal, Kimya Jones, Ravindra Kolhe. Clinical assessment of DPEP1 expression and its interacting genes in tumor (T) and adjacent normal tissue (NAT) of colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6311.

Abstract 2096: Natural killer cells inhibit CD4+ T cell mediated IL-9 production in head and neck Cancer

Abstract Head and neck squamous cell carcinoma (HNSCC) is the 6th most common cancer in the world, yet 5 year survival remains poor for those with recurrence despite advances in treatment such as immunotherapy. Checkpoint blockade substantially improved survival in ~20% of recurrent and/or metastatic HNSCC patients. However, given the lack of efficacy in most patients, and the known immunosuppressive nature of HNSCC, exploring other potential immune cell therapeutic targets is of interest. Decreased natural killer (NK) as well as increased immunosuppressive CD4+ regulatory T cells (Tregs) in both peripheral blood and the tumor microenvironment are associated with a poor prognosis in HNSCC. We discovered that the anti-diabetes drug, metformin, which is also known to improve immune cell function, not only increases peripheral NK cells in HNSCC patients to the level of healthy controls, but also suppresses IL-9 secretion from NK cells. IL-9 has been implicated as a driving factor in allergic disease, a poor prognosis factor in hematologic malignancies, and an enhancer of T-reg immunosuppressive abilities. However, the function of IL-9 in solid tumors is poorly understood. Interestingly, upon depletion of CD56+ NK and NKT cells from peripheral blood mononuclear cells (PBMCs), there was a significant increase of IL-9 secretion. This effect was negated upon depletion of CD4+ T cells suggesting that NK cells may directly or indirectly inhibit CD4+ T cell IL-9 production. In order to understand potential consequences of IL-9 overproduction, we subjected HNSCC cell lines, which we demonstrated express IL9 receptor, to exogenous IL-9 which resulted in enhanced proliferation. We also found that IL-9 plasma levels are high in HNSCC patients compared to healthy controls corroborating a potential tumorigenic role for IL-9. In order to elucidate potential mechanism(s) by which NK/NKT cells regulate CD4+ T cell production, we performed single-cell RNAseq on PBMCs upon NK and NKT cell depletion. We also performed flow cytometry to identify specific CD4+ cell types responsible for increased IL-9 production and the consequential changes in other immune cell phenotypes upon the absence of NK/NKT cells. Understanding the role of IL-9 in HNSCC will be important for utilizing IL-9 as a potential marker for HNSCC prognosis as well as a possible target for future immunotherapy approaches. Citation Format: McKenzie Crist, Maria Lehn, Vinita Takiar, Trisha Wise-Draper. Natural killer cells inhibit CD4+ T cell mediated IL-9 production in head and neck Cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2096.

STAT1 is regulated by TRIM24 and promotes immunosuppression in head and neck squamous carcinoma cells, but enhances T cell antitumour immunity in the tumour microenvironment

BackgroundHead and neck squamous cell carcinoma (HNSCC) is a significant problem and is frequently resistant to current treatments. STAT1 is important in anti-tumour immune responses against HNSCC. However, the role of STAT1 expression by tumour cells and its regulation during HNSCC is unclear.MethodsWe determined the effects of STAT1 inhibition on tumour development and immunity in CAL27 and UMSCC22A HNSCC cell lines in vitro and in a HNSCC carcinogen-induced model in vivo.ResultsSTAT1 siRNA knockdown in human HNSCC cells impaired their proliferation and expression of the immunosuppressive marker PD-L1. Stat1-deficient mice displayed increased oral lesion incidence and multiplicity during tumour carcinogenesis in vivo. Immunosuppressive markers PD-1 in CD8+ T cells and PD-L1 in monocytic MDSCs and macrophages were reduced in oral tumours and draining lymph nodes of tumour-bearing Stat1-deficient mice. However, STAT1 was required for anti-tumour functions of T cells during HNSCC in vivo. Finally, we identified TRIM24 to be a negative regulator of STAT1 that plays a similar tumorigenic function to STAT1 in vitro and thus may be a potential target when treating HNSCC.ConclusionOur findings indicate that STAT1 activity plays an important role in tumorigenicity and immunosuppression during HNSCC development.

Role of SWI/SNF chromatin remodeling genes in lung cancer development.

SWI/SNF family of chromatin remodeling complexes uses the energy of ATP to change the structure of DNA, playing key roles in DNA regulation and repair. It is estimated that up to 25% of all human cancers contain alterations in SWI/SNF, although the precise molecular mechanisms for their involvement in tumor progression are largely unknown. Despite the improvements achieved in the last decades on our knowledge of lung cancer molecular biology, it remains the major cause of cancer-related deaths worldwide and it is in urgent need for new therapeutic alternatives. We and others have described recurrent alterations in different SWI/SNF genes in nearly 20% of lung cancer patients, some of them with a significant association with worse prognosis, indicating an important role of SWI/SNF in this fatal disease. These alterations might be therapeutically exploited, as it has been shown in cellular and animal models with the use of EGFR inhibitors, DNA-damaging agents and several immunotherapy approaches. Therefore, a better knowledge of the molecular mechanisms regulated by SWI/SNF alterations in lung cancer might be translated into a therapeutic improvement of this frequently lethal disease. In this review, we summarize all the evidence of SWI/SNF alterations in lung cancer, the current knowledge about the potential mechanisms involved in their tumorigenic role, as well as the results that support a potential exploitation of these alterations to improve the treatment of lung cancer patients.

The integrated stress response in the induction of mutant KRAS lung carcinogenesis: Mechanistic insights and therapeutic implications.

The integrated stress response (ISR) is a key determinant of tumorigenesis in response to oncogenic forms of stress like genotoxic, proteotoxic and metabolic stress. ISR relies on the phosphorylation of the translation initiation factor eIF2 to promote the translational and transcriptional reprogramming of gene expression in stressed cells. While ISR promotes tumor survival under stress, its hyperactivation above a level of tolerance can also cause tumor death. The tumorigenic function of ISR has been recently demonstrated for lung adenocarcinomas (LUAD) with KRAS mutations. ISR mediates the translational repression of the dual-specificity phosphatase DUSP6 to stimulate ERK activity and LUAD growth. The significance of this finding is highlighted by the strong anti-tumor responses of ISR inhibitors in pre-clinical LUAD models. Elucidation of the mechanisms of ISR action in LUAD progression via cell-autonomous and immune regulatory mechanisms will provide a better understanding of its tumorigenic role to fully exploit its therapeutic potential in the treatment of a deadly form of cancer.

Overexpressed COL3A1 has prognostic value in human esophageal squamous cell carcinoma and promotes the aggressiveness of esophageal squamous cell carcinoma by activating the NF-κB pathway

Alpha-1 Type Ⅲ Collagen (COL3A1) encodes the Collagen alpha-1(Ⅲ) chain, which is a fibrillar collagen that exists in extensile connective tissues. Few studies have reported its role in tumorigenicity. In the present study, we identified that COL3A1 protein and mRNA expression levels were considerably up-regulated in esophageal squamous cell carcinoma (ESCC) cells in comparison with normal esophageal squamous epithelial cells (P < 0.05). Immunohistochemical (IHC) analysis of 114 paraffin-embedded archived ESCC tissues demonstrated that COL3A1 expression was positively correlated with the postoperative T stage. Univariate and multivariable analysis demonstrated that COL3A1 expression was an independent poor prognostic factor for overall survival in the whole cohort. Silencing COL3A1 inhibited, while overexpressing COL3A1 promoted, the proliferation, migration, and invasion of ESCC cells. Furthermore, down-regulation of COL3A1 expression also suppressed the growth of ESCC in subcutaneous xenograft mouse models and inhibited ESCC metastasis in lung metastasis mouse models. In addition, we proved that the tumor-promoting effect of COL3A1 on ESCC cells was related to the activation of NF-κB signaling pathway. These findings indicate that COL3A1 confers a poor prognosis and malignant phenotype by activating the NF-κB pathway in ESCC, potentially representing a novel biomarker and/or providing a new curative target for ESCC.

CDK12 promotes tumorigenesis but induces vulnerability to therapies inhibiting folate one-carbon metabolism in breast cancer

Cyclin-dependent kinase 12 (CDK12) overexpression is implicated in breast cancer, but whether it has a primary or only a cooperative tumorigenic role is unclear. Here, we show that transgenic CDK12 overexpression in the mouse mammary gland per se is sufficient to drive the emergence of multiple and multifocal tumors, while, in cooperation with known oncogenes, it promotes earlier tumor onset and metastasis. Integrative transcriptomic, metabolomic and functional data reveal that hyperactivation of the serine-glycine-one-carbon network is a metabolic hallmark inherent to CDK12-induced tumorigenesis. Consistently, in retrospective patient cohort studies and in patient-derived xenografts, CDK12-overexpressing breast tumors show positive response to methotrexate-based chemotherapy targeting CDK12-induced metabolic alterations, while being intrinsically refractory to other types of chemotherapy. In a retrospective analysis of hormone receptor-negative and lymph node-positive breast cancer patients randomized in an adjuvant phase III trial to 1-year low-dose metronomic methotrexate-based chemotherapy or no maintenance chemotherapy, a high CDK12 status predicts a dramatic reduction in distant metastasis rate in the chemotherapy-treated vs. not-treated arm. Thus, by coupling tumor progression with metabolic reprogramming, CDK12 creates an actionable vulnerability for breast cancer therapy and might represent a suitable companion biomarker for targeted antimetabolite therapies in human breast cancers.

Tumorigenic and immunological roles of Heat shock protein A2 in pancreatic cancer: a bioinformatics analysis.

Heat shock protein A2 has been reported to be tightly associated with tumorigenesis and tumor progression. This study aimed to determine the oncogenic and immunological roles of Heat shock protein A2 in pancreatic cancer by bioinformatics. Expression of Heat shock protein A2 in tumorous and normal specimens of pancreatic cancer was analyzed using the Cancer Genome Atlas and the Cancer Genome Atlas + Genotype-Tissue Expression data sets, respectively. Relationships of Heat shock protein A2 expression with immune infiltrates in pancreatic cancer were assessed. Heat shock protein A2-associated coexpressed genes in pancreatic cancer were obtained, followed by the implementation of enrichment analysis. The data demonstrated that Heat shock protein A2 was significantly overexpressed in tumorous samples compared with normal samples. Heat shock protein A2 expression was remarkably positively interrelated with CD8+ T cell, neutrophil, dendritic cell, and macrophage, but not with CD4+ T and B cells. Heat shock protein A2 expression was markedly positively relevant to both cancer-associated fibroblast and endothelial cell. Enrichment data revealed that Heat shock protein A2 was intimately involved in the tumorigenesis and progression of pancreatic cancer. Heat shock protein A2 is upregulated in pancreatic cancer and is closely associated with tumor immunity and aggressive progression.

Tumor-associated macrophage-derived exosomes transmitting miR-193a-5p promote the progression of renal cell carcinoma via TIMP2-dependent vasculogenic mimicry

Previous studies have investigated whether tumor-associated macrophages (TAMs) play tumorigenic and immunosuppressive roles to encourage cancer development, but the role of TAMs in regulating vasculogenic mimicry (VM) in clear-cell renal cell carcinoma (ccRCC) cells has not been completely clarified. We conducted immunostaining of the tumor-associated macrophage biomarkers CD68/CD163 and double staining for PAS/CD31 in ccRCC human specimens to find that higher TAM infiltration was positively correlated with VM formation. Then we demonstrated that TAM-derived exosomes downregulate TIMP2 expression in RCC cells to promote VM and invasion by shuttling miR-193a-5p. Mechanistic analysis indicated that HIF-1α upregulation in macrophages could transcriptionally increase miR-193a-5p expression. Exosome-shuttled miR-193a-5p then targeted the 3′ untranslated region (UTR) of TIMP2 mRNA to suppress its translation. A preclinical study using an in vivo orthotopic xenograft model of ccRCC in mice substantiated that TAM-derived exosomes enhance VM and enable tumor progression, which confirmed our in vitro data. Suppressing TAM-derived exosomal miR-193a-5p successfully inhibited tumor progression and metastasis. Overall, miR-193a-5p from TAM-derived exosomes downregulates the TIMP2 gene to facilitate the development of RCC, which provides a novel perspective for developing therapeutic strategies for RCC.

Yin Yang 1-stimulated long noncoding RNA bladder cancer-associated transcript 1 upregulation facilitates esophageal carcinoma progression via the microRNA-5590-3p/programmed cell death-ligand 1 pathway

ABSTRACT Esophageal carcinoma (EC) is a common gastrointestinal malignancy that poses a threat to public health worldwide. Long noncoding RNA (lncRNA) bladder cancer-associated transcript 1 (BLACAT1) exerts a tumorigenic role in several malignant tumors; nevertheless, its function in EC remains largely unknown. Besides, programmed cell death-ligand 1 (PD-L1), an oncogene in numerous human cancers, has been identified as a therapeutic target for EC. Therefore, we intended to explore the potential regulatory network involving BLACAT1 and PD-L1 in EC. In this study, we observed increased BLACAT1 and PD-L1 levels in EC tissues and EC cell lines. Moreover, YY1 could activate BLACAT1 transcription in EC cells (TE-1 and EC9706). In addition, in vitro and in vivo experiments demonstrated that BLACAT1 facilitated EC cell proliferation and metastasis and EC tumor growth. Also, the effects of BLACAT1 silencing on EC cell functions were partially reversed by PD-L1 overexpression. Besides, it was identified that BLACAT1 competed with PD-L1 to bind to miR-5590-3p in EC cells. Furthermore, miR-5590-3p suppression could abrogate the functional effects of BLACAT1 knockdown on EC cells; while PD-L1 silencing partly abolished the promoting effects of miR-5590-3p suppression on the biological functions of EC cells. To sum up, YY1-induced BLACAT1 accelerated EC progression via regulating the miR-5590-3p/PD-L1 axis.

Promotion of tumorigenesis by miR‐1260b–targeting CASP8: Potential diagnostic and prognostic marker for breast cancer

MicroRNAs are reported as promising biomarkers for the diagnosis and treatment of breast cancer. miR‐1260b is identified as a tumor‐associated noncoding microRNA in other cancers, although the role of miR‐1260b and its clinical relevance in breast cancer remain unclear. In this study, miR‐1260b as a potential prognostic biomarker was observed by univariate and multivariate Cox regression analyses in 102 breast tumor tissues. The tumorigenic role of miR‐1260b in terms of proliferation, apoptosis, and migration of breast cancer cells was investigated using gain‐ and loss‐of‐function assays in vitro. Additionally, the potential early diagnosis and treatment monitoring marker of miR‐1260b was validated in 129 plasma samples. We found that high miR‐1260b expression was markedly associated with bulky tumor size, advanced stage, and lymph node invasion. Particularly, the high–miR‐1260b‐expression group showed shorter overall survival than the low–miR‐1260b‐expression group. The inhibition of oncogenic miR‐1260b induced apoptosis and decreased migration and invasion of MDA‐MB‐231 cells. CASP8 was revealed as a direct target gene of miR‐1260b, which is closely related to apoptosis. Furthermore, miR‐1260b expression levels in plasma were significantly higher in patients with breast cancer than in healthy controls. The patients who tested positive for miR‐1260b showed 16.3‐ and 18.2‐fold higher risks in the early stage and locally advanced stage, respectively, compared with healthy controls, and the risk was decreased 6.2‐fold after neoadjuvant chemotherapy. Taken together, miR‐1260b may be a potential novel diagnostic, prognostic, and therapeutic target in breast cancer.

Lipid Droplet-Related PLIN2 in CD68+ Tumor-Associated Macrophage of Oral Squamous Cell Carcinoma: Implications for Cancer Prognosis and Immunotherapy

BackgroundPLIN2 (adipose differentiation-related protein) belongs to the perilipin family and is a marker of lipid droplets (LDs). Numerous types of tumor exhibit a high PLIN2 level, but its tumorigenic or tumor-suppressive role has been in debate. Recently, LDs serve as innate immune hubs and show antimicrobial capacity. We here aimed to investigate the heterogeneous functions of PLIN2 in the tumor microenvironment and immune regulation.MethodsThis retrospective study included 96 oral squamous cell carcinoma (OSCC) samples and analyzed the spatial distribution of PLIN2 by immunohistochemistry (IHC) and LD level by oil red O staining. A total of 21 serial sections were obtained to analyze the relationship between PLIN2 and immune cells by IHC and immunofluorescence (IF). Single-cell sequencing was used to analyze the cell locations of PLIN2. The values of diagnosis and prognosis of PLIN2 were also evaluated. Tumor Immune Estimation Resource (TIMER), cBioPortal databases, and IHC analysis were used to investigate the relationship between PLIN2 and OSCC immune microenvironment.ResultsPLIN2 was mainly expressed in tumor-infiltrating immunocytes (TIIs) of OSCC. Patients with high PLIN2 harbored more cytoplastic LDs. CD68+ tumor-associated macrophages (TAMs), instead of T cells and B cells, were found to be the main resource of PLIN2 in OSCC stroma and lung, pancreas, prostate, and testis. However, CD56+ NK cells also showed less extent of PLIN2 staining in OSCC. Moreover, patients with a high PLIN2 level in immune cells had a higher TNM stage and were susceptible to postoperative metastasis, but the escalated PLIN2 level in invasive tumor front independently predicted shorter metastasis-free survival. Furthermore, a high PLIN2 presentation in the microenvironment induced immune suppression which was featured as less infiltration of CD8+ T cells and more CD68+ TAMs and Foxp3+ Tregs, accompanied by more immune checkpoint molecules such as CSF1R, LGALS9, IL-10, CTLA-4, and TIGIT.ConclusionCD68+ TAM-derived PLIN2 might participate in regulating immune balance of OSCC patients, which provides new insight into immune checkpoint therapy.

Neuroblastoma in childhood and its potential viral involvement: A webinar by the Paediatric Virology Study Group

Neuroblastoma represents the most common and lethal solid tumour of early childhood. In view of variations in genetic elements, MYCN amplification is certainly the most prominent genetic factor occurring in 1/4 or 1/5 of children with neuroblastoma; however, overall, the pathogenesis of neuroblastoma remains to be resolved. Rare, sporadic infections with Epstein‑Barr, hepatis C virus and varicella‑zoster virus have been detected in children with neuroblastoma, while the presence of BK virus was initially claimed, but later falsified as a triggering factor for the development of high‑risk neuroblastoma. The proposed model by Professor Ugo Rovigatti, Professor of Molecular Biology at the University of Florence in Italy, is based upon infection with micro‑foci inducing virus and its potential tumorigenic role as trigger of i) high and persistent inflammation; ii) chromothripsis and genetic instability; and iii) <em>in vitro</em> cell transformation and <em>in vivo</em> carcinogenesis. Modelling is still under‑utilized and under-developed in clinical virology and cancer research; however, it is expected to play a significant role in the future, aiming to elucidate the cancer enigma. This article is based on a webinar on neuroblastoma in children, which was organised virtually on December 12, 2020, by the Institute of Paediatric Virology.

Long non-coding RNA AC087388.1 as a novel biomarker in colorectal cancer

BackgroundSeveral investigations have reported diverse roles of long non-coding RNA (lncRNA) in biological processes, tumor development, and progression of colorectal cancer (CRC). In this study, we investigated the lncRNA AC087388.1 tumorigenic role in CRC cells.MethodsThe CRC tissues were collected at the Reza Radiotherapy and Oncology Center, Mashhad, Iran. The human SW-48 and HT-29 CRC cell lines were obtained from the national cell bank of Iran. The cells were cultured according to ATCC (the American Type Culture Collection) recommendations. Quantitative real-time PCR was applied to assess the RNA expression. ShRNA transfection was done to downregulate the target gene. MTT and apoptosis assays were conducted to evaluate cell proliferation and viability, respectively. Colony formation assay, wound healing assay, and invasion assay were applied to determine growth, motility, and invasion of the cells, respectively. ENCORI online tool was used as downstream enrichment analysis.ResultsForty CRC patients were encompassed in this study. The results demonstrated that the lncRNA SLC16A1-AS1, AC087388.1, and ELFN1-AS1 were significantly overexpressed in the CRC tissues in comparison to their normal counterpart margins. All the lncRNAs have shown significant Area Under Curve (AUC) values in the patients. Downregulation of lncRNA AC087388.1 remarkably decreased the cell proliferation and viability of the CRC cells. In addition, the data demonstrated that the downregulation of lncRNA AC087388.1 significantly suppressed cell growth and colony formation capability in the cells. Also, downregulation of lncRNA AC087388.1 attenuated motility and invasion of CRC cells, and significantly decreased the expression of invasion genes. In-silico functional enrichment analysis indicated that the lncRNA AC087388.1 has contributed to crucial signaling pathways in tumorigenesis such as the p53 and Wnt signaling pathways, apoptosis, and cell cycle.ConclusionsAltogether, we showed that lncRNA AC087388.1 has an oncogenic role in tumorigenesis of CRC, and it can be considered as a novel diagnostic and prognostic biomarker in CRC.

Nano-trapping CXCL13 reduces regulatory B cells in tumor microenvironment and inhibits tumor growth

Interactions between different cell types in the tumor microenvironment (TME) affect tumor growth. Tumor-associated fibroblasts produce C-X-C motif chemokine ligand 13 (CXCL13) which recruits B cells to the TME. B-cells in the TME differentiate into regulatory B cells (Bregs) (IL-10+CD1d+CD5+CD138+CD19+). We highlight these Breg cells as a new important factor in the modulation of the immunosuppressive TME in different desmoplastic murine tumor models. In addition, CXCL13 also stimulates epithelial–mesenchymal transition (EMT) of the tumor cells. The tumorigenic roles of CXCL13 led us to explore an innovative anti-cancer strategy based on delivering plasmid DNA encoding a CXCL13 trap to reduce Bregs differentiation and normalize EMT, thereby suppressing tumor growth. CXCL13 trap suppressed tumor growth in pancreatic cancer, BRAF-mutant melanoma, and triple-negative breast cancer. In this study, following treatment, the affected tumor remained dormant resulting in prolonged progression-free survival of the host.

Autophagy Regulation on Cancer Stem Cell Maintenance, Metastasis, and Therapy Resistance.

Simple SummaryCertain types of cancer have higher relapse rates compared to others, and cancer stem cells (CSCs) have been shown as the main drivers of cancer relapse and cancer severity. This subpopulation of cells displays stem-like characteristics which bolster tumorigenesis along with metastasis and lead to poorer prognoses. Autophagy has been studied as a mechanism by which CSCs maintain stemness and acquire resistance to chemotherapy and radiation. The aim of this review is to condense and organize what has been recently published on the connection between cancer stem cells (CSCs) and autophagy. Multiple studies on autophagy have suggested that the pathway is a double-edged sword, which can either undermine or enhance CSC characteristics depending on interactions with different pathways. Thus, future research should investigate regulation of autophagy in combination with traditional cancer therapies as a possible method to effectively eliminate CSCs and minimize cancer relapse.Cancer stem cells (CSCs) are a subset of the tumor population that play critical roles in tumorigenicity, metastasis, and relapse. A key feature of CSCs is their resistance to numerous therapeutic strategies which include chemotherapy, radiation, and immune checkpoint inhibitors. In recent years, there is a growing body of literature that suggests a link between CSC maintenance and autophagy, a mechanism to recycle intracellular components during moments of environmental stress, especially since CSCs thrive in a tumor microenvironment that is plagued with hypoxia, acidosis, and lack of nutrients. Autophagy activation has been shown to aid in the upkeep of a stemness state along with bolstering resistance to cancer treatment. However, recent studies have also suggested that autophagy is a double-edged sword with anti-tumorigenic properties under certain circumstances. This review summarizes and integrates what has been published in the literature in terms of what role autophagy plays in stemness maintenance of CSCs and suggests that there is a more complex interplay between autophagy and apoptosis which involves multiple pathways of regulation. Future cancer therapy strategies are needed to eradicate this resistant subset of the cell population through autophagy regulation.

Role and Involvement of TENM4 and miR-708 in Breast Cancer Development and Therapy.

Teneurin 4 (TENM4) is a transmembrane protein that is codified by the ODZ4 gene and is involved in nervous system development, neurite outgrowth, and neuronal differentiation. In line with its involvement in the nervous system, TENM4 has also been implicated in several mental disorders such as bipolar disorder, schizophrenia, and autism. TENM4 mutations and rearrangements have recently been identified in a number of tumors. This, combined with impaired expression in tumors, suggests that it may potentially be involved in tumorigenesis. Most of the TENM4 mutations that are observed in tumors occur in breast cancer, in which TENM4 plays a role in cells’ migration and stemness. However, the functional role that TENM4 plays in breast cancer still needs to be better evaluated, and further studies are required to better understand the involvement of TENM4 in breast cancer progression. Herein, we review the currently available data for TENM4′s role in breast cancer and propose its use as both a novel target with which to ameliorate patient prognosis and as a potential biomarker. Moreover, we also report data on the tumorigenic role of miR-708 deregulation and the possible use of this miRNA as a novel therapeutic molecule, as miR-708 is spliced out from TENM4 mRNA.

Menin Enhances Androgen Receptor-Independent Proliferation and Migration of Prostate Cancer Cells.

The androgen receptor (AR) is an important therapeutic target for treating prostate cancer (PCa). Moreover, there is an increasing need for understanding the AR-independent progression of tumor cells such as neuroendocrine prostate cancer (NEPC). Menin, which is encoded by multiple endocrine neoplasia type 1 (MEN1), serves as a direct link between AR and the mixed-lineage leukemia (MLL) complex in PCa development by activating AR target genes through histone H3 lysine 4 methylation. Although menin is a critical component of AR signaling, its tumorigenic role in AR-independent PCa cells remains unknown. Here, we compared the role of menin in AR-positive and AR-negative PCa cells via RNAi-mediated or pharmacological inhibition of menin. We demonstrated that menin was involved in tumor cell growth and metastasis in PCa cells with low or deficient levels of AR. The inhibition of menin significantly diminished the growth of PCa cells and induced apoptosis, regardless of the presence of AR. Additionally, transcriptome analysis showed that the expression of many metastasis-associated genes was perturbed by menin inhibition in AR-negative DU145 cells. Furthermore, wound-healing assay results showed that menin promoted cell migration in AR-independent cellular contexts. Overall, these findings suggest a critical function of menin in tumorigenesis and provide a rationale for drug development against menin toward targeting high-risk metastatic PCa, especially those independent of AR.

A Review on Epigenetic Effects of Environmental Factors Causing and Inhibiting Cancer.

Epigenetic modifications refer to reversible changes in gene expression. Epigenetic changes include DNA methylation, histone modification, and non-coding RNAs that are collectively called epigenome. Various epigenetic effects account for the main impacts of environment and lifestyle on multifactorial diseases, such as cancers. The environmental impacts on cancers act as double-edged swords. While some of them are involved in cancer development, some others contribute to preventing it. In this review article, the keywords "cancer", "epigenetic", "lifestyle", "carcinogen", " cancer inhibitors" and related words were searched to finding a link between environmental factors and epigenetic mechanisms influencing cancer in ISI, PUBMED, SCOPUS, and Google Scholar databases. Based on the literature, environmental factors that are effective in cancer development or cancer prevention will be divided into physical, chemical, biological, and lifestyle types in this review. Different types of epigenetic mechanisms known for each of these agents will be addressed. Unregulated changes in epigenome play roles in tumorigenicity and cancer development. The action mechanism and genes targeted which are related to the signaling pathway for epigenetic alterations determine whether environmental agents are carcinogenic or prevent cancer. Having knowledge about the effective factors and related mechanisms such as epigenetic on cancer can help to prevent and improve cancer treatment.