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Nature Communications Jan 2024Oncogenic KRAS mutations are well-described functionally and are known to drive tumorigenesis. Recent reports describe a significant prevalence of KRAS allelic...
Oncogenic KRAS mutations are well-described functionally and are known to drive tumorigenesis. Recent reports describe a significant prevalence of KRAS allelic imbalances or gene dosage changes in human cancers, including loss of the wild-type allele in KRAS mutant cancers. However, the role of wild-type KRAS in tumorigenesis and therapeutic response remains elusive. We report an in vivo murine model of colorectal cancer featuring deletion of wild-type Kras in the context of oncogenic Kras. Deletion of wild-type Kras exacerbates oncogenic KRAS signalling through MAPK and thus drives tumour initiation. Absence of wild-type Kras potentiates the oncogenic effect of KRASG12D, while incidentally inducing sensitivity to inhibition of MEK1/2. Importantly, loss of the wild-type allele in aggressive models of KRASG12D-driven CRC significantly alters tumour progression, and suppresses metastasis through modulation of the immune microenvironment. This study highlights the critical role for wild-type Kras upon tumour initiation, progression and therapeutic response in Kras mutant CRC.
Topics: Humans; Mice; Animals; Proto-Oncogene Proteins p21(ras); Allelic Imbalance; Genes, ras; Cell Transformation, Neoplastic; Colorectal Neoplasms; Mutation; Tumor Microenvironment
PubMed: 38168062
DOI: 10.1038/s41467-023-44342-4 -
The American Journal of Pathology Sep 2023The atypical protein kinase/ATPase RIO kinase (RIOK)-1 is involved in pre-40S ribosomal subunit production, cell-cycle progression, and protein arginine...
The atypical protein kinase/ATPase RIO kinase (RIOK)-1 is involved in pre-40S ribosomal subunit production, cell-cycle progression, and protein arginine N-methyltransferase 5 methylosome substrate recruitment. RIOK1 overexpression is a characteristic of several malignancies and is correlated with cancer stage, therapy resistance, poor patient survival, and other prognostic factors. However, its role in prostate cancer (PCa) is unknown. In this study, the expression, regulation, and therapeutic potential of RIOK1 in PCa were examined. RIOK1 mRNA and protein expression were elevated in PCa tissue samples and correlated with proliferative and protein homeostasis-related pathways. RIOK1 was identified as a downstream target gene of the c-myc/E2F transcription factors. Proliferation of PCa cells was significantly reduced with RIOK1 knockdown and overexpression of the dominant-negative RIOK1-D324A mutant. Biochemical inhibition of RIOK1 with toyocamycin led to strong antiproliferative effects in androgen receptor-negative and -positive PCa cell lines with EC values of 3.5 to 8.8 nmol/L. Rapid decreases in RIOK1 protein expression and total rRNA content, and a shift in the 28S/18S rRNA ratio, were found with toyocamycin treatment. Apoptosis was induced with toyocamycin treatment at a level similar to that with the chemotherapeutic drug docetaxel used in clinical practice. In summary, the current study indicates that RIOK1 is a part of the MYC oncogene network, and as such, could be considered for future treatment of patients with PCa.
Topics: Male; Humans; Genes, myc; Protein Kinases; Adenosine Triphosphatases; Toyocamycin; Cell Proliferation; Prostatic Neoplasms; E2F Transcription Factors; Cell Line, Tumor; Gene Expression Regulation, Neoplastic
PubMed: 37301535
DOI: 10.1016/j.ajpath.2023.05.013 -
Journal of Advanced Research Dec 2023Aberrations in MYC underlie a large proportion of liver hepatocellular carcinoma (LIHC) cases; however, MYC is difficult to target because of its undruggable structure....
BACKGROUND
Aberrations in MYC underlie a large proportion of liver hepatocellular carcinoma (LIHC) cases; however, MYC is difficult to target because of its undruggable structure. We aimed to uncover MYC-associated molecular targets to provide new strategies for LIHC treatment.
METHODS
LIHC transcriptome datasets and clinical information were obtained from The Cancer Genome Atlas. A series of bioinformatics analyses were performed for 370 patients who were stratified based on the median MYC expression level (high-MYC group and low-MYC group). Correlation analysis was performed to determine relationships between the expression of key MYC-associated genes and prognosis, DNA promotor methylation, and immune cell infiltration. Gene ontology and Kyoto Encyclopedia of Genes and Genomes Pathway enrichment analyses were performed to elucidate the functions of these genes in LIHC. Their expression and functions in LIHC were further verified using transgenic mice overexpressing c-Myc under control of the hepatocyte-specific promoter (Alb-Cre).
RESULTS
AURKB, CCNB2, and CDKN3 were overexpressed in LIHC patients with high MYC expression and were associated with poor prognosis. Upregulation of these 3 genes was significantly correlated with hypomethylated promoter status, advanced T stage, metastasis, and immune cell infiltration in LIHC patients. Functional enrichment analyses indicated that these genes participate in the "p53 signaling pathway" and "cell cycle". Furthermore, RT-PCR and IHC analysis revealed that their mRNA and protein expression levels were upregulated in an Alb-Cre;cMYC mouse model. Drugs that target these 3 MYC-related genes were identified.
CONCLUSION
Taken together, our results identify biomarkers of potential utility for managing liver cancer therapy owing to their significance in tumorigenesis, proliferation, and tumor immunity.
Topics: Animals; Mice; Humans; Carcinoma, Hepatocellular; Liver Neoplasms; Genes, myc; Genes, cdc
PubMed: 36716957
DOI: 10.1016/j.jare.2023.01.010 -
Cancer Science Nov 2023Zinc finger protein 500 (ZNF500) has an unknown expression pattern and biological function in human tissues. Our study revealed that the ZNF500 mRNA and protein levels...
Zinc finger protein 500 (ZNF500) has an unknown expression pattern and biological function in human tissues. Our study revealed that the ZNF500 mRNA and protein levels were higher in breast cancer tissues than those in their normal counterparts. However, ZNF500 expression was negatively correlated with advanced TNM stage (p = 0.018), positive lymph node metastasis (p = 0.014), and a poor prognosis (p < 0.001). ZNF500 overexpression abolished in vivo and in vitro breast cancer cell proliferation by activating the p53-p21-E2F4 signaling axis and directly interacting with p53 via its C2H2 domain. This may prevent ubiquitination of p53 in a manner that is competitive to MDM2, thus stabilizing p53. When ZNF500-∆C2H2 was overexpressed, the suppressed proliferation of breast cancer cells was neutralized in vitro and in vivo. In human breast cancer tissues, ZNF500 expression was positively correlated with p53 (p = 0.022) and E2F4 (p = 0.004) expression. ZNF500 expression was significantly lower in patients with Miller/Payne Grade 1-2 than in those with Miller/Payne Grade 3-5 (p = 0.012). ZNF500 suppresses breast cancer cell proliferation and sensitizes cells to chemotherapy.
Topics: Female; Humans; Breast Neoplasms; Cell Proliferation; Proto-Oncogene Proteins c-mdm2; Signal Transduction; Tumor Suppressor Protein p53
PubMed: 37700392
DOI: 10.1111/cas.15947 -
Cancer Biology & Medicine Jun 2024Targeted therapy is crucial for advanced colorectal cancer (CRC) positive for genetic drivers. With advances in deep sequencing technology and new targeted drugs,... (Review)
Review
Targeted therapy is crucial for advanced colorectal cancer (CRC) positive for genetic drivers. With advances in deep sequencing technology and new targeted drugs, existing standard molecular pathological detection systems and therapeutic strategies can no longer meet the requirements for careful management of patients with advanced CRC. Thus, rare genetic variations require diagnosis and targeted therapy in clinical practice. Rare gene mutations, amplifications, and rearrangements are usually associated with poor prognosis and poor response to conventional therapy. This review summarizes the clinical diagnosis and treatment of rare genetic variations, in genes including erb-b2 receptor tyrosine kinase 2 (ERBB2), B-Raf proto-oncogene, serine/threonine kinase (BRAF), ALK receptor tyrosine kinase/ROS proto-oncogene 1, receptor tyrosine kinase (ALK/ROS1), neurotrophic receptor tyrosine kinases (NTRKs), ret proto-oncogene (RET), fibroblast growth factor receptor 2 (FGFR2), and epidermal growth factor receptor (EGFR), to enhance understanding and identify more accurate personalized treatments for patients with rare genetic variations.
Topics: Humans; Colorectal Neoplasms; Proto-Oncogene Mas; Genetic Variation; Mutation; Proto-Oncogene Proteins c-ret; Molecular Targeted Therapy; Proto-Oncogene Proteins B-raf; Precision Medicine; Biomarkers, Tumor; Protein-Tyrosine Kinases; Proto-Oncogene Proteins
PubMed: 38940668
DOI: 10.20892/j.issn.2095-3941.2024.0026 -
Cancer Letters Mar 2024The highly heterogenous nature of colorectal cancer can significantly hinder its early and accurate diagnosis, eventually contributing to high mortality rates. The... (Review)
Review
The highly heterogenous nature of colorectal cancer can significantly hinder its early and accurate diagnosis, eventually contributing to high mortality rates. The adenoma-carcinoma sequence and serrated polyp-carcinoma sequence are the two most common sequences in sporadic colorectal cancer. Genetic alterations in adenomatous polyposis coli (APC), v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) and tumour protein 53 (TP53) genes are critical in adenoma-carcinoma sequence, whereas v-Raf murine sarcoma viral oncogene homolog B (BRAF) and MutL Homolog1 (MLH1) are driving oncogenes in the serrated polyp-carcinoma sequence. Sporadic mutations in these genes contribute differently to colorectal cancer pathogenesis by introducing distinct alterations in several signalling pathways that rely on the endosome-lysosome system. Unsurprisingly, the endosome-lysosome system plays a pivotal role in the hallmarks of cancer and contributes to specialised colon function. Thus, the endosome-lysosome system might be distinctively influenced by different mutations and these alterations may contribute to the heterogenous nature of sporadic colorectal cancer. This review highlights potential connections between major sporadic colorectal cancer mutations and the diverse pathogenic mechanisms driven by the endosome-lysosome system in colorectal carcinogenesis.
Topics: Animals; Mice; Humans; Proto-Oncogene Proteins B-raf; Proto-Oncogene Proteins p21(ras); Colorectal Neoplasms; Mutation; Adenoma; Carcinoma
PubMed: 38290660
DOI: 10.1016/j.canlet.2024.216639 -
The Journal of Clinical Investigation Mar 2024The mammalian SUMO-targeted E3 ubiquitin ligase Rnf4 has been reported to act as a regulator of DNA repair, but the importance of RNF4 as a tumor suppressor has not been...
The mammalian SUMO-targeted E3 ubiquitin ligase Rnf4 has been reported to act as a regulator of DNA repair, but the importance of RNF4 as a tumor suppressor has not been tested. Using a conditional-knockout mouse model, we deleted Rnf4 in the B cell lineage to test the importance of RNF4 for growth of somatic cells. Although Rnf4-conditional-knockout B cells exhibited substantial genomic instability, Rnf4 deletion caused no increase in tumor susceptibility. In contrast, Rnf4 deletion extended the healthy lifespan of mice expressing an oncogenic c-myc transgene. Rnf4 activity is essential for normal DNA replication, and in its absence, there was a failure in ATR-CHK1 signaling of replication stress. Factors that normally mediate replication fork stability, including members of the Fanconi anemia gene family and the helicases PIF1 and RECQL5, showed reduced accumulation at replication forks in the absence of RNF4. RNF4 deficiency also resulted in an accumulation of hyper-SUMOylated proteins in chromatin, including members of the SMC5/6 complex, which contributes to replication failure by a mechanism dependent on RAD51. These findings indicate that RNF4, which shows increased expression in multiple human tumor types, is a potential target for anticancer therapy, especially in tumors expressing c-myc.
Topics: Animals; Humans; Mice; Ataxia Telangiectasia Mutated Proteins; B-Lymphocytes; Carcinogenesis; Checkpoint Kinase 1; DNA Replication; Genomic Instability; Mice, Knockout; Nuclear Proteins; Proto-Oncogene Proteins c-myc; Signal Transduction; Sumoylation; Ubiquitin-Protein Ligases
PubMed: 38530355
DOI: 10.1172/JCI167419 -
Biology Direct Oct 2023Bcl-B is a poorly understood protein of the Bcl-2 family that is highly expressed in many healthy tissues and tumor types. Bcl-B is considered an antiapoptotic protein,... (Review)
Review
Bcl-B is a poorly understood protein of the Bcl-2 family that is highly expressed in many healthy tissues and tumor types. Bcl-B is considered an antiapoptotic protein, but many reports have revealed its contradictory roles in different cancer types. In this mini-review, we elucidate the functions of Bcl-B in normal conditions and various pathologies, its regulation of programmed cell death, its oncogene/oncosuppressor activity in tumorigenesis, its impact on drug-acquired resistance, and possible approaches to inhibit Bcl-B.
Topics: Humans; Proto-Oncogene Proteins c-bcl-2; Apoptosis; Neoplasms
PubMed: 37899453
DOI: 10.1186/s13062-023-00431-4 -
BMC Cancer Nov 2023RAS mutations affect prognosis in patients with metastatic colorectal cancer (mCRC) and have been identified as strong negative predictive markers for anti-epidermal... (Meta-Analysis)
Meta-Analysis
BACKGROUND
RAS mutations affect prognosis in patients with metastatic colorectal cancer (mCRC) and have been identified as strong negative predictive markers for anti-epidermal growth factor receptor monoclonal antibody (anti-EGFR mAb) therapy, but many tumors containing wild-type RAS genes still do not respond to these therapies. Some additional biomarkers may have prognostic or predictive roles, but conclusions remain controversial.
METHODS
We performed a meta-analysis and systematic review of randomized controlled trials comparing anti-EGFR mAb therapy with alternative therapy that investigated the prognostic and predictive impact of additional biomarkers in RAS wild-type (wt) mCRC patients. Hazard ratios (HRs) and 95% confidence intervals (CIs) for progression-free survival (PFS) and overall survival (OS) and odds ratios (ORs) for objective response rate (ORR) were calculated. The prognostic value of biomarkers was investigated by separately pooling HR and OR for different treatment groups in an individual study. The predictive value was assessed by pooling study interactions between treatment effects and biomarker subgroups.
RESULTS
Thirty publications reporting on eighteen trials were selected, including a total of 13,507 patients. In prognostic analysis, BRAF mutations were associated with poorer PFS [HRs = 3.76 (2.47-5.73) and 2.69 (1.82-3.98)] and OS [HRs = 2.66 (1.95-3.65) and 2.45 (1.55-3.88)] in both the experimental and control arms; low miR-31-3p expression appeared to have longer PFS and OS. In terms of predictive effect, a lack of response to anti-EGFR therapy was observed in patients with BRAF mutant tumors (P < 0.01 for PFS). Patients with tumors with any mutation in the KRAS/NRAS/BRAF/PIK3CA gene also showed similar results compared with all wild-type tumors (P for PFS, OS, and ORR were < 0.01, < 0.01 and 0.01, respectively). While low miR-31-3p expression could predict PFS (P = 0.01) and OS (P = 0.04) benefit. The prognostic and predictive value regarding PIK3CA mutations, PTEN mutations or deletions, EGFR, EREG/AREG, HER2, HER3, and HER4 expression remains uncertain.
CONCLUSIONS
In RAS wt mCRC patients receiving EGFR-targeted therapy, BRAF mutation is a powerful prognostic and therapy-predictive biomarker, with no effect found for PIK3CA mutation, PTEN mutation or deletion, but the combined biomarker KRAS/NRAS/BRAF/PIK3CA mutations predict resistance to anti-EGFR therapy. Low miR-31-3p expression may have positive prognostic and therapy predictive effects. Evidence on the prognostic and predictive roles of EGFR and its ligands, and HER2/3/4 is insufficient.
Topics: Humans; Prognosis; Proto-Oncogene Proteins B-raf; Colorectal Neoplasms; Proto-Oncogene Proteins p21(ras); ErbB Receptors; Antibodies, Monoclonal; Colonic Neoplasms; Rectal Neoplasms; Biomarkers; Class I Phosphatidylinositol 3-Kinases; Mutation; MicroRNAs; Biomarkers, Tumor
PubMed: 37974093
DOI: 10.1186/s12885-023-11600-z -
Melanoma Research Oct 2023For patients with locally advanced or metastatic melanoma who have BRAF V600 activating mutations, combination therapy with BRAF and MEK inhibitors is now the standard...
For patients with locally advanced or metastatic melanoma who have BRAF V600 activating mutations, combination therapy with BRAF and MEK inhibitors is now the standard of care. The combination of encorafenib, a highly selective adenosine triphosphate-competitive BRAF inhibitor, plus binimetinib, a potent, selective, allosteric, non-adenosine triphosphate-competitive MEK1/2 inhibitor, was approved by the US Food and Drug Administration for unresectable or metastatic melanoma with BRAF V600E or V600K mutations based on data from the phase III COLUMBUS study (NCT01909453). Clinical data evaluating BRAF and MEK inhibitor combinations in advanced melanoma indicate a specific profile of adverse events that includes serious retinopathy, skin disorders, and cardiovascular toxicities. Here we provide an overview of the rationale for combining BRAF and MEK inhibitors for the treatment of melanoma, long-term safety results from COLUMBUS, and guidance on managing the most common adverse events associated with this combination based on clinical experience. Proactive and appropriate management of adverse events can allow for longer treatment durations and may result in better treatment outcomes.
Topics: Humans; Melanoma; Skin Neoplasms; Proto-Oncogene Proteins B-raf; Antineoplastic Combined Chemotherapy Protocols; Protein Kinase Inhibitors; Mutation; Mitogen-Activated Protein Kinase Kinases
PubMed: 37534686
DOI: 10.1097/CMR.0000000000000891