Oncogenic Signaling by Leukemia-Associated Mutant Cbl Proteins

: Central dogma of molecular biology has remained cornerstone of classical molecular biology but serendipitous discovery of microRNAs (miRNAs) in nematodes paradigmatically shifted our current understanding of the intricate mech-anisms which occur during transitions from transcription to translation. Discovery of miRNA captured tremendous attention and appreciation and we had witnessed an explosion in the field of non-coding RNAs. Ground-breaking discoveries in the field of non-coding RNAs have helped in better characterization of microRNAs and long non-coding RNAs (LncRNAs). There is an ever-increasing list of miRNA targets which are regulated by MALAT1 to stimulate or repress expression of tar-get genes. However, in this review our main focus is to summarize mechanistic insights related to MALAT1-mediated regu-lation of oncogenic signaling pathways. We have discussed how MALAT1 modulated TGF/SMAD and Hippo pathways in various cancers. We have also comprehensively summarized how JAK/STAT and Wnt/β-catenin pathways stimulated MALAT1 expression and consequentially how MALAT1 potentiated these signaling cascades to promote cancer. MALAT1 research has undergone substantial broadening however, there is still a need to identify additional mechanisms. MALAT1 is involved in multi-layered regulation of multiple transduction cascades and detailed analysis of different pathways will be helpful in getting a step closer to individualized medicine.

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The m6A RNA methylation regulates oncogenic signaling pathways driving cell malignant transformation and carcinogenesis

Molecular Cancer ◽

10.1186/s12943-021-01356-0 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Mohammad Burhan Uddin ◽

Zhishan Wang ◽

Chengfeng Yang

Keyword(s):

Signaling Pathways ◽

Malignant Transformation ◽

Noncoding Rna ◽

Rna Modification ◽

Oncogenic Signaling ◽

Aberrant Expression ◽

Rna Methylation ◽

Rna Molecules ◽

M6a Rna Methylation ◽

Oncogenic Signaling Pathways

AbstractThe m6A RNA methylation is the most prevalent internal modification in mammalian mRNAs which plays critical biological roles by regulating vital cellular processes. Dysregulations of the m6A modification due to aberrant expression of its regulatory proteins are frequently observed in many pathological conditions, particularly in cancer. Normal cells undergo malignant transformation via activation or modulation of different oncogenic signaling pathways through complex mechanisms. Accumulating evidence showing regulation of oncogenic signaling pathways at the epitranscriptomic level has added an extra layer of the complexity. In particular, recent studies demonstrated that, in many types of cancers various oncogenic signaling pathways are modulated by the m6A modification in the target mRNAs as well as noncoding RNA transcripts. m6A modifications in these RNA molecules control their fate and metabolism by regulating their stability, translation or subcellular localizations. In this review we discussed recent exciting studies on oncogenic signaling pathways that are modulated by the m6A RNA modification and/or their regulators in cancer and provided perspectives for further studies. The regulation of oncogenic signaling pathways by the m6A modification and its regulators also render them as potential druggable targets for the treatment of cancer.

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Whole-exome mutational landscape of neuroendocrine carcinomas of the gallbladder

Signal Transduction and Targeted Therapy ◽

10.1038/s41392-020-00412-3 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Fatao Liu ◽

Yongsheng Li ◽

Dongjian Ying ◽

Shimei Qiu ◽

Yong He ◽

...

Keyword(s):

Gene Mutations ◽

Large Cell ◽

Molecular Signatures ◽

Single Nucleotide Variants ◽

Oncogenic Signaling ◽

Single Nucleotide ◽

Whole Exome ◽

Deadly Disease ◽

Oncogenic Signaling Pathways ◽

Neuroendocrine Carcinomas

AbstractNeuroendocrine carcinoma (NEC) of the gallbladder (GB-NEC) is a rare but extremely malignant subtype of gallbladder cancer (GBC). The genetic and molecular signatures of GB-NEC are poorly understood; thus, molecular targeting is currently unavailable. In the present study, we applied whole-exome sequencing (WES) technology to detect gene mutations and predicted somatic single-nucleotide variants (SNVs) in 15 cases of GB-NEC and 22 cases of general GBC. In 15 GB-NECs, the C > T mutation was predominant among the 6 types of SNVs. TP53 showed the highest mutation frequency (73%, 11/15). Compared with neuroendocrine carcinomas of other organs, significantly mutated genes (SMGs) in GB-NECs were more similar to those in pulmonary large-cell neuroendocrine carcinomas (LCNECs), with driver roles for TP53 and RB1. In the COSMIC database of cancer-related genes, 211 genes were mutated. Strikingly, RB1 (4/15, 27%) and NAB2 (3/15, 20%) mutations were found specifically in GB-NECs; in contrast, mutations in 29 genes, including ERBB2 and ERBB3, were identified exclusively in GBC. Mutations in RB1 and NAB2 were significantly related to downregulation of the RB1 and NAB2 proteins, respectively, according to immunohistochemical (IHC) data (p values = 0.0453 and 0.0303). Clinically actionable genes indicated 23 mutated genes, including ALK, BRCA1, and BRCA2. In addition, potential somatic SNVs predicted by ISOWN and SomVarIUS constituted 6 primary COSMIC mutation signatures (1, 3, 30, 6, 7, and 13) in GB-NEC. Genes carrying somatic SNVs were enriched mainly in oncogenic signaling pathways involving the Notch, WNT, Hippo, and RTK-RAS pathways. In summary, we have systematically identified the mutation landscape of GB-NEC, and these findings may provide mechanistic insights into the specific pathogenesis of this deadly disease.

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Disruption of the HER3-PI3K-mTOR oncogenic signaling axis and PD-1 blockade as a multimodal precision immunotherapy in head and neck cancer

Nature Communications ◽

10.1038/s41467-021-22619-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Zhiyong Wang ◽

Yusuke Goto ◽

Michael M. Allevato ◽

Victoria H. Wu ◽

Robert Saddawi-Konefka ◽

...

Keyword(s):

Squamous Cell Carcinoma ◽

Head And Neck ◽

Mtor Inhibitors ◽

Immune Checkpoint Blockade ◽

Mtor Signaling ◽

Wild Type ◽

Oncogenic Signaling ◽

Signaling Axis ◽

Oncogenic Driver ◽

Cancer Remission

AbstractImmune checkpoint blockade (ICB) therapy has revolutionized head and neck squamous cell carcinoma (HNSCC) treatment, but <20% of patients achieve durable responses. Persistent activation of the PI3K/AKT/mTOR signaling circuitry represents a key oncogenic driver in HNSCC; however, the potential immunosuppressive effects of PI3K/AKT/mTOR inhibitors may limit the benefit of their combination with ICB. Here we employ an unbiased kinome-wide siRNA screen to reveal that HER3, is essential for the proliferation of most HNSCC cells that do not harbor PIK3CA mutations. Indeed, we find that persistent tyrosine phosphorylation of HER3 and PI3K recruitment underlies aberrant PI3K/AKT/mTOR signaling in PIK3CA wild type HNSCCs. Remarkably, antibody-mediated HER3 blockade exerts a potent anti-tumor effect by suppressing HER3-PI3K-AKT-mTOR oncogenic signaling and concomitantly reversing the immune suppressive tumor microenvironment. Ultimately, we show that HER3 inhibition and PD-1 blockade may provide a multimodal precision immunotherapeutic approach for PIK3CA wild type HNSCC, aimed at achieving durable cancer remission.

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Oncolytic Virotherapy: The Cancer Cell Side

Cancers ◽

10.3390/cancers13050939 ◽

2021 ◽

Vol 13 (5) ◽

pp. 939

Author(s):

Marcelo Ehrlich ◽

Eran Bacharach

Keyword(s):

Viral Replication ◽

Cancer Cell ◽

Cell Metabolism ◽

Tumor Development ◽

Oncolytic Viruses ◽

Oncogenic Signaling ◽

Functional Connection ◽

Immunity Genes ◽

Cancer Cell Metabolism ◽

Editing Process

Cell autonomous immunity genes mediate the multiple stages of anti-viral defenses, including recognition of invading pathogens, inhibition of viral replication, reprogramming of cellular metabolism, programmed-cell-death, paracrine induction of antiviral state, and activation of immunostimulatory inflammation. In tumor development and/or immunotherapy settings, selective pressure applied by the immune system results in tumor immunoediting, a reduction in the immunostimulatory potential of the cancer cell. This editing process comprises the reduced expression and/or function of cell autonomous immunity genes, allowing for immune-evasion of the tumor while concomitantly attenuating anti-viral defenses. Combined with the oncogene-enhanced anabolic nature of cancer-cell metabolism, this attenuation of antiviral defenses contributes to viral replication and to the selectivity of oncolytic viruses (OVs) towards malignant cells. Here, we review the manners by which oncogene-mediated transformation and tumor immunoediting combine to alter the intracellular milieu of tumor cells, for the benefit of OV replication. We also explore the functional connection between oncogenic signaling and epigenetic silencing, and the way by which restriction of such silencing results in immune activation. Together, the picture that emerges is one in which OVs and epigenetic modifiers are part of a growing therapeutic toolbox that employs activation of anti-tumor immunity for cancer therapy.

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Protein Acetylation at the Interface of Genetics, Epigenetics and Environment in Cancer

Metabolites ◽

10.3390/metabo11040216 ◽

2021 ◽

Vol 11 (4) ◽

pp. 216

Author(s):

Mio Harachi ◽

Kenta Masui ◽

Webster K. Cavenee ◽

Paul S. Mischel ◽

Noriyuki Shibata

Keyword(s):

Cancer Cells ◽

Intracellular Signaling ◽

Cancer Biology ◽

High Resolution Mass Spectrometry ◽

Metabolic Reprogramming ◽

Protein Acetylation ◽

Protein Activity ◽

Oncogenic Signaling ◽

Intermediary Metabolites ◽

Novel Therapeutic Strategies

Metabolic reprogramming is an emerging hallmark of cancer and is driven by abnormalities of oncogenes and tumor suppressors. Accelerated metabolism causes cancer cell aggression through the dysregulation of rate-limiting metabolic enzymes as well as by facilitating the production of intermediary metabolites. However, the mechanisms by which a shift in the metabolic landscape reshapes the intracellular signaling to promote the survival of cancer cells remain to be clarified. Recent high-resolution mass spectrometry-based proteomic analyses have spotlighted that, unexpectedly, lysine residues of numerous cytosolic as well as nuclear proteins are acetylated and that this modification modulates protein activity, sublocalization and stability, with profound impact on cellular function. More importantly, cancer cells exploit acetylation as a post-translational protein for microenvironmental adaptation, nominating it as a means for dynamic modulation of the phenotypes of cancer cells at the interface between genetics and environments. The objectives of this review were to describe the functional implications of protein lysine acetylation in cancer biology by examining recent evidence that implicates oncogenic signaling as a strong driver of protein acetylation, which might be exploitable for novel therapeutic strategies against cancer.

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MiR-200c-3p Contrasts PD-L1 Induction by Combinatorial Therapies and Slows Proliferation of Epithelial Ovarian Cancer through Downregulation of β-Catenin and c-Myc

Cells ◽

10.3390/cells10030519 ◽

2021 ◽

Vol 10 (3) ◽

pp. 519

Author(s):

Eleni Anastasiadou ◽

Elena Messina ◽

Tiziana Sanavia ◽

Lucia Mundo ◽

Federica Farinella ◽

...

Keyword(s):

Ovarian Cancer ◽

Epithelial Ovarian Cancer ◽

Therapeutic Strategy ◽

Target Genes ◽

Ovarian Cancer Cells ◽

Oncogenic Signaling ◽

Experimental Conditions ◽

Skov3 Cells ◽

In Silico Analyses ◽

Post Therapy

Conventional/targeted chemotherapies and ionizing radiation (IR) are being used both as monotherapies and in combination for the treatment of epithelial ovarian cancer (EOC). Several studies show that these therapies might favor oncogenic signaling and impede anti-tumor responses. MiR-200c is considered a master regulator of EOC-related oncogenes. In this study, we sought to investigate if chemotherapy and IR could influence the expression of miR-200c-3p and its target genes, like the immune checkpoint PD-L1 and other oncogenes in a cohort of EOC patients’ biopsies. Indeed, PD-L1 expression was induced, while miR-200c-3p was significantly reduced in these biopsies post-therapy. The effect of miR-200c-3p target genes was assessed in miR-200c transfected SKOV3 cells untreated and treated with olaparib and IR alone. Under all experimental conditions, miR-200c-3p concomitantly reduced PD-L1, c-Myc and β-catenin expression and sensitized ovarian cancer cells to olaparib and irradiation. In silico analyses further confirmed the anti-correlation between miR-200c-3p with c-Myc and β-catenin in 46 OC cell lines and showed that a higher miR-200c-3p expression associates with a less tumorigenic microenvironment. These findings provide new insights into how miR-200c-3p could be used to hold in check the adverse effects of conventional chemotherapy, targeted therapy and radiation therapy, and offer a novel therapeutic strategy for EOC.

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EphA2 and EGFR: Friends in Life, Partners in Crime. Can EphA2 Be a Predictive Biomarker of Response to Anti-EGFR Agents?

Cancers ◽

10.3390/cancers13040700 ◽

2021 ◽

Vol 13 (4) ◽

pp. 700

Author(s):

Mario Cioce ◽

Vito Michele Fazio

Keyword(s):

Colorectal Cancer ◽

Solid Tumors ◽

Receptor Tyrosine Kinase ◽

Predictive Biomarker ◽

Eph Receptors ◽

Oncogenic Signaling ◽

Induced Stress ◽

Molecular Determinants ◽

Signaling Axis ◽

Context Specific

The Eph receptors represent the largest group among Receptor Tyrosine kinase (RTK) families. The Eph/ephrin signaling axis plays center stage during development, and the deep perturbation of signaling consequent to its dysregulation in cancer reveals the multiplicity and complexity underlying its function. In the last decades, they have emerged as key players in solid tumors, including colorectal cancer (CRC); however, what causes EphA2 to switch between tumor-suppressive and tumor-promoting function is still an active theater of investigation. This review summarizes the recent advances in understanding EphA2 function in cancer, with detail on the molecular determinants of the oncogene-tumor suppressor switch function of EphA2. We describe tumor context-specific examples of EphA2 signaling and the emerging role EphA2 plays in supporting cancer—stem—cell-like populations and overcoming therapy-induced stress. In such a frame, we detail the interaction of the EphA2 and EGFR pathway in solid tumors, including colorectal cancer. We discuss the contribution of the EphA2 oncogenic signaling to the resistance to EGFR blocking agents, including cetuximab and TKIs.

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