[Retracted] Oncogenic miR-23a-5p is associated with cellular function in RCC

Following the publication of this article, a concerned reader drew to the Editor's attention that, for the invasion and migration assay data shown in Fig. 4 on p. 2314, three pairs of data panels were overlapping, such that data which were intended to show the results from differently performed experiments were obtained from a smaller number of original sources. Moreover, after having conducted an internal investigation, the Editorial Office also observed that some of the flow cytometric data shown in Fig. 6 were duplicated in Fig. 7. Considering the number of overlapping data panels that have been identified in this published paper, the Editor of Molecular Medicine Reports has concluded that the article should be retracted from the publication on account of a lack of confidence in the integrity of the data. Upon contacting the authors about this matter, they accepted the decision to retract this paper. The Editor apologizes to the readership for any inconvenience caused, and thanks the interested reader for drawing this matter to our attention. [Molecular Medicine Reports 16: 2309-2317, 2017; DOI: 10.3892/mmr.2017.6829].

Integrated mutational landscape analysis of poorly differentiated high-grade neuroendocrine carcinoma of the uterine cervix

High-grade neuroendocrine cervical cancers (NETc) are exceedingly rare, highly aggressive tumors. We analyzed 64 NETc tumor samples by whole-exome sequencing (WES). Human papillomavirus DNA was detected in 65.6% (42/64) of the tumors. Recurrent mutations were identified in PIK3CA, KMT2D/MLL2, K-RAS, ARID1A, NOTCH2, and RPL10. The top mutated genes included RB1, ARID1A, PTEN, KMT2D/MLL2, and WDFY3, a gene not yet implicated in NETc. Somatic CNV analysis identified two copy number gains (3q27.1 and 19q13.12) and five copy number losses (1p36.21/5q31.3/6p22.2/9q21.11/11p15.5). Also, gene fusions affecting the ACLY-CRHR1 and PVT1-MYC genes were identified in one of the eight samples subjected to RNA sequencing. To resolve evolutionary history, multiregion WES in NETc admixed with adenocarcinoma cells was performed (i.e., mixed-NETc). Phylogenetic analysis of mixed-NETc demonstrated that adenocarcinoma and neuroendocrine elements derive from a common precursor with mutations typical of adenocarcinomas. Over one-third (22/64) of NETc demonstrated a mutator phenotype of C > T at CpG consistent with deficiencies in MBD4, a member of the base excision repair (BER) pathway. Mutations in the PI3K/AMPK pathways were identified in 49/64 samples. We used two patient-derived-xenografts (PDX) (i.e., NET19 and NET21) to evaluate the activity of pan-HER (afatinib), PIK3CA (copanlisib), and ATR (elimusertib) inhibitors, alone and in combination. PDXs harboring alterations in the ERBB2/PI3K/AKT/mTOR/ATR pathway were sensitive to afatinib, copanlisib, and elimusertib (P < 0.001 vs. controls). However, combinations of copanlisib/afatinib and copanlisib/elimusertib were significantly more effective in controlling NETc tumor growth. These findings define the genetic landscape of NETc and suggest that a large subset of these highly lethal malignancies might benefit from existing targeted therapies.

RAD52-dependent mitotic DNA synthesis is required for genome stability in Cyclin E1-overexpressing cells

Overexpression of Cyclin E1 perturbs DNA replication, resulting in DNA lesions and genomic instability. Consequently, Cyclin E1-overexpressing cancer cells increasingly rely on DNA repair, including RAD52-mediated break-induced replication during interphase. We show that not all DNA lesions induced by Cyclin E1 overexpression are resolved during interphase. While DNA lesions upon Cyclin E1 overexpression are induced in S phase, a significant fraction of these lesions is transmitted into mitosis. Cyclin E1 overexpression triggers mitotic DNA synthesis (MiDAS) in a RAD52-dependent fashion. Chemical or genetic inactivation of MiDAS enhances mitotic aberrations and persistent DNA damage. Mitosis-specific degradation of RAD52 prevents Cyclin E1-induced MiDAS and reduces the viability of Cyclin E1-overexpressing cells, underscoring the relevance of RAD52 during mitosis to maintain genomic integrity. Finally, analysis of breast cancer samples reveals a positive correlation between Cyclin E1 amplification and RAD52 expression. These findings demonstrate the importance of suppressing mitotic defects in Cyclin E1-overexpressing cells through RAD52.

The UBE2F-CRL5ASB11-DIRAS2 axis is an oncogene and tumor suppressor cascade in pancreatic cancer cells

UBE2F, a neddylation E2, neddylates CUL5 to activate cullin-RING ligase-5, upon coupling with neddylation E3 RBX2/SAG. Whether and how UBE2F controls pancreatic tumorigenesis is previously unknown. Here, we showed that UBE2F is essential for the growth of human pancreatic cancer cells with KRAS mutation. In the mouse KrasG12D pancreatic ductal adenocarcinoma (PDAC) model, Ube2f deletion suppresses cerulein-induced pancreatitis, and progression of acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia. Mechanistically, Ube2f deletion inactivates the Mapk-c-Myc signals via blocking ubiquitylation of Diras2, a substrate of CRL5Asb11 E3 ligase. Biologically, DIRAS2 suppresses growth and survival of human pancreatic cancer cells harboring mutant KRAS, and Diras2 deletion largely rescues the phenotypes induced by Ube2f deletion. Collectively, Ube2f or Diras2 plays a tumor-promoting or tumor-suppressive role in the mouse KrasG12D PDAC model, respectively. The UBE2F-CRL5ASB11 axis could serve as a valid target for pancreatic cancer, whereas the levels of UBE2F or DIRAS2 may serve as prognostic biomarkers for PDAC patients.

[Corrigendum] microRNA‑181a‑5p functions as an oncogene in renal cell carcinoma

Following the publication of the above article and a corrigendum in 2018 that corrected details of the correspondence information for authors, errors made in Fig. 5 and the funding details (doi: 10.3892/mmr.2018.9117), an interested reader drew to the authors' attention that, in Fig. 6 on p. 8515 showing the results of cell migration and invasion assay experiments, a pair of data panels were overlapping, such that data which were intended to show the results from differently performed experiments appeared to have been derived from the same original source. After having consulted their original data, the authors have realized that Fig. 6 was assembled incorrectly, The revised version of Fig. 6, now showing the correct data for the 'ACHN/migratory/NC' experiment, is shown on the next page. Note that all the authors approve of the publication of this corrigendum, and the authors are grateful to the Editor of Molecular Medicine Reports for granting them the opportunity to publish this. The authors regret their oversight in allowing this error to be included in the paper, and also apologize to the readership for any inconvenience caused. [Molecular Medicine Reports 17: 8510‑8517, 2018; DOI: 10.3892/mmr.2018.8899].

"The 10th International MDM2 Workshop": Opening up new avenues for MDM2 and p53 research, the First International MDM2 Workshop in Asia

The 10th International MDM2 Workshop was held at the National Cancer Center Research Institute (NCCRI) in Tokyo, Japan, from October 15 to 18, 2023. It attracted 166 participants from 12 countries. The meeting featured 52 talks and 41 poster presentations. In the first special session, six invited speakers gave educational and outstanding talks on breakthroughs in MDM2 research. Three keynote speakers presented emerging p53-independent functions of MDM2/MDM4, functional association of MDM2/p53 with cancer immunity, and drug discovery targeting the MDM2/MDM4-p53 pathway. Additionally, 19 invited speakers introduced their new findings. Twenty-one presenters, many of whom were young investigators, postdocs, and students, were selected from submitted abstracts and reported their exciting and unpublished results. For poster presenters, outstanding poster awards were given to the best presenters. There were many inspiring questions and discussions throughout the meeting. Social events like a welcome party, a workshop dinner, and an optional tour enabled further scientific interactions among the participants. The meeting successfully provided an exciting platform for scientific exchange. The experience gained from organizing this meeting will be handed over to the next organizers of the 11th International MDM2 Workshop.

Regulating Protein-RNA Interactions: Advances in Targeting the LIN28/Let-7 Pathway

Originally discovered in C. elegans, LIN28 is an evolutionarily conserved zinc finger RNA-binding protein (RBP) that post-transcriptionally regulates genes involved in developmental timing, stem cell programming, and oncogenesis. LIN28 acts via two distinct mechanisms. It blocks the biogenesis of the lethal-7 (let-7) microRNA (miRNA) family, and also directly binds messenger RNA (mRNA) targets, such as IGF-2 mRNA, and alters downstream splicing and translation events. This review focuses on the molecular mechanism of LIN28 repression of let-7 and current strategies to overcome this blockade for the purpose of cancer therapy. We highlight the value of the LIN28/let-7 pathway as a drug target, as multiple oncogenic proteins that the pathway regulates are considered undruggable due to their inaccessible cellular location and lack of cavities for small molecule binding.

Advances in MiRNAs Involved in Endometrial Carcinoma

Endometrial carcinoma (EC) is a common malignancy worldwide. Existing evidence has revealed that EC could be associated with abnormal gene expression. Meantime, evidence supports that miRNAs act as critical regulators in gene expression through the binding to the 3'- untranslated region (3'-UTR). Accordingly, this review concludes some recent studies focusing on miRNAs that influence EC, aiming at understanding the association between miRNAs and EC more clearly and providing a reference for further studies on miRNA-related drugs treating EC.

SKping cell cycle regulation: role of ubiquitin ligase SKP2 in hematological malignancies

SKP2 (S-phase kinase-associated protein 2) is a member of the F-box family of substrate-recognition subunits in the SCF ubiquitin-protein ligase complexes. It is associated with ubiquitin-mediated degradation in the mammalian cell cycle components and other target proteins involved in cell cycle progression, signal transduction, and transcription. Being an oncogene in solid tumors and hematological malignancies, it is frequently associated with drug resistance and poor disease outcomes. In the current review, we discussed the novel role of SKP2 in different hematological malignancies. Further, we performed a limited in-silico analysis to establish the involvement of SKP2 in a few publicly available cancer datasets. Interestingly, our study identified Skp2 expression to be altered in a cancer-specific manner. While it was found to be overexpressed in several cancer types, few cancer showed a down-regulation in SKP2. Our review provides evidence for developing novel SKP2 inhibitors in hematological malignancies. We also investigated the effect of SKP2 status on survival and disease progression. In addition, the role of miRNA and its associated families in regulating Skp2 expression was explored. Subsequently, we predicted common miRNAs against Skp2 genes by using miRNA-predication tools. Finally, we discussed current approaches and future prospective approaches to target the Skp2 gene by using different drugs and miRNA-based therapeutics applications in translational research.

Metabolic reprogramming directed by super-enhancers in tumors: An emerging landscape

Metabolic reprogramming is an essential hallmark of tumors, and metabolic abnormalities are strongly associated with the malignant phenotype of tumor cells. This is closely related to transcriptional dysregulation. Super-enhancers are extremely active cis-regulatory regions in the genome, and can amalgamate a complex set of transcriptional regulatory components that are crucial for establishing tumor cell identity, promoting tumorigenesis, and enhancing aggressiveness. In addition, alterations in metabolic signaling pathways are often accompanied by changes in super-enhancers. Presently, there is a surge in interest in the potential pathogenesis of various tumors through the transcriptional regulation of super-enhancers and oncogenic mutations in super-enhancers. In this review, we summarize the functions of super-enhancers, oncogenic signaling pathways, and tumor metabolic reprogramming. In particular, we focus on the role of the super-enhancer in tumor metabolism and its impact on metabolic reprogramming. This review also discusses the prospects and directions in the field of super-enhancer and metabolic reprogramming.

DPP2/7 is a Potential Predictor of Prognosis and Target in Immunotherapy in Colorectal Cancer: An Integrative Multi-omics Analysis

BACKGROUND

Colorectal cancer (CRC) ranks among the leading causes of cancerrelated deaths.

OBJECTIVE

This study aimed to illuminate the relationship between DPP7 (also known as DPP2) and CRC through a combination of bioinformatics and experimental methodologies.

METHODS

A multi-dimensional bioinformatic analysis on DPP7 was executed, covering its expression, survival implications, clinical associations, functional roles, immune interactions, and drug sensitivities. Experimental validations involved siRNA-mediated DPP7 knockdown and various cellular assays.

RESULTS

Data from the Cancer Genome Atlas (TCGA) identified high DPP7 expression in solid CRC tumors, with elevated levels adversely affecting patient prognosis. A shift from the N0 to the N2 stage in CRC was associated with increased DPP7 expression. Functional insights indicated the involvement of DPP7 in cancer progression, particularly in extracellular matrix disassembly. Immunological analyses showed its association with immunosuppressive entities, and in vitro experiments in CRC cell lines underscored its oncogenic attributes.

CONCLUSION

DPP7 could serve as a CRC prognosis marker, functioning as an oncogene and representing a potential immunotherapeutic target.

Dual role of GRHL3 in bladder carcinogenesis depending on histological subtypes

The effect of grainyhead-like transcription factor 3 (GRHL3) on cancer development depends on the cancer subtypes as shown in tumor entities such as colorectal or oral squamous cell carcinomas. Here, we analyzed the subtype-specific role of GRHL3 in bladder carcinogenesis, comparing common urothelial carcinoma (UC) with squamous bladder cancer (sq-BLCA). We examined GRHL3 mRNA and protein expression in cohorts of patient samples, its prognostic role and its functional impact on tumorigeneses in different molecular and histopathological subtypes of bladder cancer. We showed for GRHL3 a reverse expression in squamous and urothelial bladder cancer subtypes. Stably GRHL3-overexpressing EJ28, J82, and SCaBER in vitro models revealed a tumor-suppressive function in squamous and an oncogenic role in the urothelial cancer cells affecting cell and colony growth, and migratory and invasive capacities. Transcriptomic profiling demonstrated highly subtype-specific GRHL3-regulated expression networks coined by the enrichment of genes involved in integrin-mediated pathways. In SCaBER, loss of ras homolog family member A (RHOA) GTPase activity was demonstrated to be associated with co-regulation of eukaryotic translation initiation factor 4E family member 3 (EIF4E3), a potential tumor suppressor gene. Thus, our data provide for the first time a detailed insight into the role of the transcription factor GRHL3 in different histopathological subtypes of bladder cancer.

Comparative Expression Analysis of TP53 Tumor Suppressor and MDM2 Oncogene in Colorectal Adenocarcinoma

Background/Aim

The tumor protein 53 (TP53) tumor suppressor protein (17p13.1) acts as a significant regulator for the cell cycle normal function. The gene is frequently mutated in colorectal adenocarcinoma (CRC) patients and is associated to poor prognosis and low response rates to chemo-targeted therapy. Our purpose was to correlate TP53 expression with Mouse Double Minute 2 Homolog (MDM2), a proto-oncogene (12q14.3) and a major negative regulator in the TP53-MDM2 auto-regulatory pathway.

Materials and Methods

A total of forty (n=40) colorectal adenocarcinoma (CRC) cases were included in this study. An immunohistochemistry-based assay was implemented by using anti-TP53 and anti-MDM2 antibodies in the corresponding tissue sections. Additionally, a digital image analysis assay was implemented for objectively measuring TP53/MDM2 immunostaining intensity levels.

Results

TP53 protein overexpression was detected in 27/40 (67.5%), whereas MDM2 overexpression in 28/40 (70%) cases. Interestingly, in 21/40 (52.5%) cases, a combined TP53/MDM2 co-expression was detected, whereas in 6/40 (15%), a combined loss of expression was identified (overall co-expression: p=0.119). p53 overexpression was significantly correlated to grade of the examined cases (p=0.001), whereas MDM2 to stage and max diameter of the malignancies (p=0.001 and 0.024, respectively).

Conclusion

TP53/MDM2 over expression is a frequent and significant genetic event in CRCs associated with an aggressive biological behavior, as a result of increased dedifferentiation grade and advanced stage/elevated tumor volume, respectively. MDM2 oncogene overactivation combined with mutated and overexpressed TP53 is observed in sub-groups of patients leading to specific gene/protein signatures - targets for personalized chemotherapeutic approaches.

Analysis and Investigation of Bioinformatics and Epigenetics Reveal the Underlying Mechanisms by which FLOT2 Modulates the Progression of Diffuse Large B-cell Lymphoma

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) poses a significant threat to the quality of life for people worldwide. Regrettably, effective treatment strategies for this disease remain elusive in clinical practice due to the unclear understanding of its molecular mechanisms. Therefore, this study was devised to address these issues and identify novel diagnostic, therapeutic, and prognostic biomarkers for DLBCL.

METHODS

Gene expression and clinical data for DLBCL patients were retrieved from The Cancer Genome Atlas (TCGA) database, and relevant clinical data, tumor mutational burden (TMB), and gene expression levels were extracted. Bioinformatics analysis was conducted to screen for differentially expressed genes (DEGs). The prognostic significance of flotillin-2 (FLOT2) was assessed using Kaplan-Meier survival analysis. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analyses were employed to evaluate mRNA and protein levels of the genes. Cell proliferation, apoptosis, and invasion were assessed using cell counting kit-8 (CCK-8) assay, flow cytometry analysis, and Transwell assay, respectively.

RESULTS

Our bioinformatics analysis revealed that FLOT2 was significantly overexpressed in DLBCL tissues compared to normal tissues, a finding corroborated by subsequent immunohistochemistry staining, qRT-PCR, and Western blot analyses. To elucidate its biological functions, shRNAs targeting FLOT2 were transfected into DLBCL cell lines (LY-3 and U2932), resulting in suppressed cell proliferation and invasion, while promoting apoptosis. Furthermore, a positive correlation between TMB and FLOT2 expression in DLBCL was observed. Subsequently, quanTIseq was utilized to calculate the immune score and assess FLOT2 gene expression. In DLBCL, FLOT2 gene expression was found to be associated with T cell CD4+ (non-regulatory) (p < 0.01), monocytes (p < 0.05), and uncharacterized cells (p < 0.05). Regarding immune checkpoint markers, including the cluster of differentiation 274 (CD274), cytotoxic T lymphocyte-associated antigen-4 (CTLA4), hepatitis A virus cellular receptor 2 (HAVCR2), lymphocyte activation gene-3 (LAG3), programmed cell death protein 1 (PDCD1), programmed cell death 1 ligand 2 (PDCD1LG2), Siglec-15 (SIGLEC15), and T cell immunoreceptor with Ig and ITIM domains (TIGIT), our analysis indicated that in DLBCL, FLOT2 exhibited a relationship only with TIGIT (p < 0.05).

CONCLUSIONS

In summary, FLOT2 functions as an oncogene and is linked to DLBCL prognosis and the tumor microenvironment. Targeting FLOT2 deletion emerges as a novel strategy to impede DLBCL aggressiveness by inhibiting cell proliferation and invasion, ultimately inducing apoptotic cell death.

Kinome-wide siRNA screen identifies a DCLK2-TBK1 oncogenic signaling axis in clear cell renal cell carcinoma

TANK-binding kinase 1 (TBK1) is a potential therapeutic target in multiple cancers, including clear cell renal cell carcinoma (ccRCC). However, targeting TBK1 in clinical practice is challenging. One approach to overcome this challenge would be to identify an upstream TBK1 regulator that could be targeted therapeutically in cancer specifically. In this study, we perform a kinome-wide small interfering RNA (siRNA) screen and identify doublecortin-like kinase 2 (DCLK2) as a TBK1 regulator in ccRCC. DCLK2 binds to and directly phosphorylates TBK1 on Ser172. Depletion of DCLK2 inhibits anchorage-independent colony growth and kidney tumorigenesis in orthotopic xenograft models. Conversely, overexpression of DCLK2203, a short isoform that predominates in ccRCC, promotes ccRCC cell growth and tumorigenesis in vivo. Mechanistically, DCLK2203 elicits its oncogenic signaling via TBK1 phosphorylation and activation. Taken together, these results suggest that DCLK2 is a TBK1 activator and potential therapeutic target for ccRCC.

Review: Are moles senescent?

Melanocytic nevi (skin moles) have been regarded as a valuable example of cell senescence occurring in vivo. However, a study of induced nevi in a mouse model reported that the nevi were arrested by cell interactions rather than a cell-autonomous process like senescence, and that size distributions of cell nests within nevi could not be accounted for by a stochastic model of oncogene-induced senescence. Moreover, others reported that some molecular markers used to identify cell senescence in human nevi are also found in melanoma cells-not senescent. It has thus been questioned whether nevi really are senescent, with potential implications for melanoma diagnosis and therapy. Here I review these areas, along with the genetic, biological, and molecular evidence supporting senescence in nevi. In conclusion, there is strong evidence that cells of acquired human benign (banal) nevi are very largely senescent, though some must contain a minor non-senescent cell subpopulation. There is also persuasive evidence that this senescence is primarily induced by dysfunctional telomeres rather than directly oncogene-induced.

Role of Epiregulin in Lung Tumorigenesis and Therapeutic Resistance

Epidermal growth factor (EGF) signaling regulates multiple cellular processes and plays an essential role in tumorigenesis. Epiregulin (EREG), a member of the EGF family, binds to the epidermal growth factor receptor (EGFR) and ErbB4, and it stimulates EGFR-related downstream pathways. Increasing evidence indicates that both the aberrant expression and oncogenic function of EREG play pivotal roles in tumor development in many human cancers, including non-small cell lung cancer (NSCLC). EREG overexpression is induced by activating mutations in the EGFR, KRAS, and BRAF and contributes to the aggressive phenotypes of NSCLC with oncogenic drivers. Recent studies have elucidated the roles of EREG in a tumor microenvironment, including the epithelial-mesenchymal transition, angiogenesis, immune evasion, and resistance to anticancer therapy. In this review, we summarized the current understanding of EREG as an oncogene and discussed its oncogenic role in lung tumorigenesis and therapeutic resistance.

NOTCH Signaling Pathway: Occurrence, Mechanism, and NOTCH-Directed Therapy for the Management of Cancer

It is now well understood that many signaling pathways are vital in carrying out and controlling essential pro-survival and pro-growth cellular functions. The NOTCH signaling pathway, a highly conserved evolutionary signaling pathway, has been thoroughly studied since the discovery of NOTCH phenotypes about 100 years ago in Drosophila melanogaster. Abnormal NOTCH signaling has been linked to the pathophysiology of several diseases, notably cancer. In tumorigenesis, NOTCH plays the role of a "double-edged sword," that is, it may act as an oncogene or as a tumor suppressor gene depending on the nature of the context. However, its involvement in several cancers and inhibition of the same provides targeted therapy for the management of cancer. The use of gamma (γ)-secretase inhibitors and monoclonal antibodies for cancer treatment involved NOTCH receptors inhibition, leading to the possibility of a targeted approach for cancer treatment. Likewise, several natural compounds, including curcumin, resveratrol, diallyl sulfide, and genistein, also play a dynamic role in the management of cancer by inhibition of NOTCH receptors. This review outlines the functions and structure of NOTCH receptors and their associated ligands with the mechanism of the signaling pathway. In addition, it also emphasizes the role of NOTCH-targeted nanomedicine in various cancer treatment strategies.

Identification of ITGB4 as a novel tumor promoting gene in lung adenocarcinoma (LUAD)

As the most frequently diagnosed cancer, lung cancer (LC) is the most common cause of cancer‑related death worldwide. In total, ~85% of malignant lung tumors belong to non‑small cell LC, of which ~50% are lung adenocarcinoma (LUAD). Integrin subunit β4 (ITGB4) is upregulated in lung glandular cancer and elevated ITGB4 levels predict an adverse clinical outcome. However, the biological function of ITGB4 in promoting LUAD progression remains unclear. In the present study, the upregulation of ITGB4 in LUAD tissue samples was demonstrated. To understand the biological role of ITGB4, ITGB4 expression was knocked down in A549 and PC9 cells through transfection with specific small interfering RNAs. The results demonstrated that the downregulation of ITGB4 attenuated A549 and PC9 cell proliferation, promoted cell apoptosis and inhibited colony formation, cell migration and cell invasion. To understand the mechanism of ITGB4, high throughput sequencing was performed using ITGB4‑knocked down A549 cells, followed by bioinformatics analysis. It was found that the genes upregulated by ITGB4 were significantly enriched in metabolism and related pathways, and the genes downregulated by ITGB4 were enriched in cell cycle and related pathways. In conclusion, the findings of the present study highlighted the oncogenic function of ITGB4 in LUAD and uncovered potential mechanisms fundamental to the progression of the disease.

[Retracted] Downregulation of ROS‑FIG inhibits cell proliferation, colony‑formation, cell cycle progression, migration and invasion, while inducing apoptosis in intrahepatic cholangiocarcinoma cells

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that the western blotting data shown in Fig. 9 were strikingly similar to data appearing in different form in other articles written by different authors at different research institutes that had either already been published elsewhere prior to the submission of this paper to International Journal of Molecular Medicine, or were under consideration for publication at around the same time. In view of the fact that certain of these data had already apparently been published previously, the Editor of International Journal of Molecular Medicine has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [International Journal of Molecular Medicine 34: 661‑668, 2014; 10.3892/ijmm.2014.1823].

Rho GTPase-activating protein 1 promotes hepatocellular carcinoma progression via modulation by CircPIP5K1A/MiR-101-3p

AIM

There has been an increased focus on regulating cell function with Rho family GTPases, including proliferation, migration/invasion, polarity, and adhesion. Due to the challenges involved in targeting Rho family GTPases directly, it may be more effective to target their regulators, such as Rho GTPase-activating protein 1 (ARHGAP1). This present research was performed to define the clinical significance of ARHGAP1 expression, as well as its regulatory mechanisms in hepatocellular carcinoma.

METHODS

ARHGAP1 and miR-101-3p expression of liver cancer patients, and their relevance with clinicopathological characteristics and prognosis were analyzed by the Cancer Genome Atlas sequencing data, and verified using samples of hepatocellular carcinoma patients. The interactions between miR-101-3p and ARHGAP1 or circPIP5K1A were validated by bioinformatic analyses, as well as confirmed by quantitative reverse transcription polymerase chain reaction, western blotting, and dual-luciferase reporter analysis. Plate clonality assays, cell adhesion and migration experiments, and proliferation experiments were used for assessing the participation of the circPIP5K1A/miR-101-3p/ARHGAP1 pathway in cell proliferation and motility.

RESULTS

Elevated ARHGAP1 and reduced miR-101-3p expression are related to poorer survival. MiR-101-3p targets ARHGAP1 to suppress hepatocellular carcinoma cell colony formation and invasion, whereas miR-101-3p inhibitor reverses liver cancer proliferation and metastasis suppression caused by ARHGAP1 knockdown. In addition, circPIP5K1A, which is mainly distributed in the cytosol, showed carcinogenic effects by sponging miR-101-3p, thus regulating ARHGAP1 expression.

CONCLUSIONS

ARHGAP1 serves as an oncogenic gene in liver cancer, and the expression thereof is regulated by circPIP5K1A through sponging miR-101-3p.

Two decades of a protooncogene TBL1XR1: from a transcription modulator to cancer therapeutic target

Transducin beta-like 1X-related protein 1 (TBL1XR1) was discovered two decades ago and was implicated as part of the nuclear transcription corepressor complex. Over the past 20 years, the emerging oncogenic function of TBL1XR1 in cancer development has been discovered. Recent studies have highlighted that the genetic aberrations of TBL1XR1 in cancers, especially in hematologic tumors, are closely associated with tumorigenesis. In solid tumors, TBL1XR1 is proposed to be a promising prognostic biomarker due to the correlation between abnormal expression and clinicopathological parameters. Post-transcriptional and post-translational modification are responsible for the expression and function of TBL1XR1 in cancer. TBL1XR1 exerts its functional role in various processes that involves cell cycle and apoptosis, cell proliferation, resistance to chemotherapy and radiotherapy, cell migration and invasion, stemness and angiogenesis. Multitude of cancer-related signaling cascades like Wnt-β-catenin, PI3K/AKT, ERK, VEGF, NF-κB, STAT3 and gonadal hormone signaling pathways are tightly modulated by TBL1XR1. This review provided a comprehensive overview of TBL1XR1 in tumorigenesis, shedding new light on TBL1XR1 as a promising diagnostic biomarker and druggable target in cancer.

Targeting Protein Tyrosine Phosphatases to Improve Cancer Immunotherapies

Advances in immunotherapy have brought significant therapeutic benefits to many cancer patients. Nonetheless, many cancer types are refractory to current immunotherapeutic approaches, meaning that further targets are required to increase the number of patients who benefit from these technologies. Protein tyrosine phosphatases (PTPs) have long been recognised to play a vital role in the regulation of cancer cell biology and the immune response. In this review, we summarize the evidence for both the pro-tumorigenic and tumour-suppressor function of non-receptor PTPs in cancer cells and discuss recent data showing that several of these enzymes act as intracellular immune checkpoints that suppress effective tumour immunity. We highlight new data showing that the deletion of inhibitory PTPs is a rational approach to improve the outcomes of adoptive T cell-based cancer immunotherapies and describe recent progress in the development of PTP inhibitors as anti-cancer drugs.

Oncogenic Potential of Replication Factor C Subunit 4: Correlations with Tumor Progression and Assessment of Potential Inhibitors

Replication Factor C Subunit 4 (RFC4), an oncogene implicated in many human cancers, has yet to be extensively studied in many cancer types to determine its expression patterns and tumor tissue function. Various bioinformatics tools were used to analyze RFC4 as a potential oncogene and therapeutic target across many cancers. We first examined RFC4 expression levels in several human tumor types to determine relationships with tumor grade, stage, metastasis, and patient survival. We also examined RFC4's genetic changes, epigenetic methylation, and effect on tumor microenvironment (TME) immune cell infiltration. We also analyzed RFC4's connections with immunological checkpoints to identify potential molecular pathways involved in carcinogenesis. Our findings show that RFC4 is upregulated in several tumor types and associated with poor prognoses in many human cancers. This study shows that RFC4 significantly affects the tumor immunological microenvironment, specifically immune cell populations. Finally, we screened for RFC4-inhibiting pharmacological compounds with anti-cancer potential. This study fully elucidates RFC4's carcinogenic activities, emphasizing its potential as a prognostic biomarker and a target for anti-cancer therapy.

ZNF217: An Oncogenic Transcription Factor and Potential Therapeutic Target for Multiple Human Cancers

Zinc finger protein 217 (ZNF217) is one of the well-researched members of the Krüppel-like factor transcription factor family. ZNF217 possesses a characteristic structure of zinc finger motifs and plays a crucial role in regulating the biological activities of cells. Recent findings have revealed that ZNF217 is strongly associated with multiple aspects of cancer progression, impacting patient prognosis. Notably, ZNF217 is subject to regulation by non-coding RNAs, suggesting the potential for targeted manipulation of such RNAs as a robust therapeutic avenue for managing cancer in the future. The main purpose of this article is to provide a detailed examination of the role of ZNF217 in human malignant tumors and the regulation of its expression, and to offer new perspectives for cancer treatment.

An oncogene regulating chromatin favors response to immunotherapy: Oncogene CHAF1A and immunotherapy outcomes

Many biological processes related to cell function and fate begin with chromatin alterations, and many factors associated with the efficacy of immune checkpoint inhibitors (ICIs) are actually downstream events of chromatin alterations, such as genome changes, neoantigen production, and immune checkpoint expression. However, the influence of genes as chromatin regulators on the efficacy of ICIs remains elusive, especially in gastric cancer (GC). In this study, thirty out of 1593 genes regulating chromatin associated with a favorable prognosis were selected for GC. CHAF1A, a well-defined oncogene, was identified as the highest linkage hub gene. High CHAF1A expression were associated with microsatellite instability (MSI), high tumor mutation burden (TMB), high tumor neoantigen burden (TNB), high expressions of PD-L1 and immune effector genes, and live infiltration of immune cells. High CHAF1A expression indicated a favorable response and prognosis in immunotherapy of several cohorts, which was independent of MSI, TMB, TNB, PD-L1 expression, immune phenotype and transcriptome scoring, and improved patient selection based on these classic biomarkers. In vivo, CHAF1A knockdown alone inhibited tumor growth but it impaired the effect of an anti-PD-1 antibody by increasing the relative tumor proliferation rate and decreasing the survival benefit, potentially through the activation of TGF-β signaling. In conclusion, CHAF1A may be a novel biomarker for improving patient selection in immunotherapy.

Corrigendum: Serum IgG antibodies from pregnant women reacting to mimotopes of Simian virus 40 large T antigen, the viral oncoprotein

[This corrects the article DOI: 10.3389/fimmu.2017.00411.].

Germinal Center Cytokines Driven Epigenetic Control of Epstein-Barr Virus Latency Gene Expression

Epstein-Barr virus (EBV) persistently infects 95% of adults worldwide and is associated with multiple human lymphomas that express characteristic EBV latency programs used by the virus to navigate the B-cell compartment. Upon primary infection, the EBV latency III program, comprised of six Epstein-Barr Nuclear Antigens (EBNA) and two Latent Membrane Protein (LMP) antigens, drives infected B-cells into germinal center (GC). By incompletely understood mechanisms, GC microenvironmental cues trigger the EBV genome to switch to the latency II program, comprised of EBNA1, LMP1 and LMP2A and observed in GC-derived Hodgkin lymphoma. To gain insights into pathways and epigenetic mechanisms that control EBV latency reprogramming as EBV-infected B-cells encounter microenvironmental cues, we characterized GC cytokine effects on EBV latency protein expression and on the EBV epigenome. We confirmed and extended prior studies highlighting GC cytokine effects in support of the latency II transition. The T-follicular helper cytokine interleukin 21 (IL-21), which is a major regulator of GC responses, and to a lesser extent IL-4 and IL-10, hyper-induced LMP1 expression, while repressing EBNA expression. However, follicular dendritic cell cytokines including IL-15 and IL-27 downmodulate EBNA but not LMP1 expression. CRISPR editing highlighted that STAT3 and STAT5 were necessary for cytokine mediated EBNA silencing via epigenetic effects at the EBV genomic C promoter. By contrast, STAT3 was instead necessary for LMP1 promoter epigenetic remodeling, including gain of activating histone chromatin marks and loss of repressive polycomb repressive complex silencing marks. Thus, EBV has evolved to coopt STAT signaling to oppositely regulate the epigenetic status of key viral genomic promoters in response to GC cytokine cues.

Exploring antiproliferative activities and kinase profile of ortho-substituted N-(4-(2-(benzylamino)-2-oxoethyl)phenyl)benzamides

Designing kinase inhibitors that bind to the substrate site of oncogenic kinases in a promising, albeit less explored, approach to kinase inhibition as it was sought to avoid the issue of untoward off-target modulations. Our previously identified compound KAC-12 with a meta-chlorophenyl substitution was an example of this approach. While it showed confirmed inhibitory activity against cancer cells, this substitution shifted the profile of affected targets away from Src/tubulin which were seen with the parent KX-01. In this paper, we synthesized compounds with ortho-substitutions, and we investigated the effect of such substitutions on their cellular and subcellular activities. The compound N-(4-(2-(benzylamino)-2-oxoethyl)phenyl)-2-(morpholine-4-carbonyl)benzamide (4) exhibited substantial activities against cell lines such HCT116 (IC50 of 0.97 μM) and IC50 HL60 (2.84 μM). Kinase profiling showed that compound 4 trended consistently with KAC-12 as it did not affect Src, but it had more impact on members of the Src family of kinases (SFK) such as Yes, Hck, Fyn, Lck, and Lyn. Both compounds exhibited profound downregulation effects on Erk1/2 but differed on others such as GSK3α/β and C-Jun. Collectively, this study further support to the hypothesis that small structural changes might bring higher changes in their kinome profile.

CircRNA Hsa_circ_0120175 Promotes Ovarian Cancer Tumorigenesis and Predicts a Poor Prognosis

BACKGROUND

Circular RNA is a type of non-coding RNA that is commonly found in eukaryotic genomes. They play an essential role in the biological processes of cell proliferation and cell apoptosis involved in normal development and abnormal tumorigenesis. In this study, we examined whether that the circular RNA GENE hsa_circ_0120175 is substantially expressed in epithelial ovarian cancer, and then explored whether hsa_circ_0120175 plays an important role in the occurrence and development of ovarian cancer.

METHODS

A total of 40 patients with ovarian cancer were included in this study, and tissue samples were collected from both ovarian cancer tissues and paracancer tissues. The levels of hsa_circ_0120175 expression were determined using qRT-PCR in both varian cancer cells and tissues. This study assessed the impact of hsa_circ_0120175 on cellular proliferation, migration, and invasion using various in vitro assays with cultured ovarian carcinoma cells.

RESULTS

Hsa_circ_0120175 was highly expressed in both human tissues and ovarian cancer cells. In ovarian cancer patients, the expression level of hsa_circ_0120175 was significantly different among The International Federation of Gynecology and Obstetrics (FIGO) stages (p = 0.03), and the difference was statistically significant. Multivariate Cox regression analysis showed that lymph node metastasis was independently related to Overall Survival (OS), and the difference was statistically significant (p = 0.033). In vitro, decreasing hsa_circ_0120175 significantly reduced ovarian carcinoma cell proliferation, migration, and invasion (p < 0.05).

CONCLUSIONS

Hsa_circ_0120175 has the potential to serve as a biomarker for diagnosing and treating ovarian carcinoma. This is because it promotes cellular proliferation, migration, and invasion in epithelial ovarian carcinoma.

Oncogenic role of FOXM1 in human prostate cancer (Review)

Prostate cancer is the leading cause of cancer‑related mortality among men worldwide. In particular, castration‑resistant prostate cancer presents a formidable clinical challenge and emphasizes the need to develop novel therapeutic strategies. Forkhead box M1 (FOXM1) is a multifaceted transcription factor that is implicated in the acquisition of the multiple cancer hallmark capabilities in prostate cancer cells, including sustaining proliferative signaling, resisting cell death and the activation of invasion and metastasis. Elevated FOXM1 expression is frequently observed in prostate cancer, and in particular, FOXM1 overexpression is closely associated with poor clinical outcomes in patients with prostate cancer. In the present review, recent advances in the understanding of the oncogenic role of deregulated FOXM1 expression in prostate cancer were highlighted. In addition, the molecular mechanisms by which FOXM1 regulates prostate cancer development and progression were described, thereby providing knowledge and a conceptual framework for FOXM1. The present review also provided valuable insight into the inherent challenges associated with translating biomedical knowledge into effective therapeutic strategies for prostate cancer.

The oncogenic role of LGR6 overexpression induced by aberrant Wnt/β-catenin signaling in lung cancer

BACKGROUND

Molecular abnormalities in the Wnt/β-catenin pathway confer malignant phenotypes in lung cancer. Previously, we identified the association of leucine-rich repeat-containing G protein-coupled receptor 6 (LGR6) with oncogenic Wnt signaling, and its downregulation upon β-catenin knockdown in non-small cell lung cancer (NSCLC) cells carrying CTNNB1 mutations. The aim of this study was to explore the mechanisms underlying this association and the accompanying phenotypes.

METHODS

LGR6 expression in lung cancer cell lines and surgical specimens was analyzed using quantitative RT-PCR and immunohistochemistry. Cell growth was assessed using colony formation assay. Additionally, mRNA sequencing was performed to compare the expression profiles of cells subjected to different treatments.

RESULTS

LGR6 was overexpressed in small cell lung cancer (SCLC) and NSCLC cell lines, including the CTNNB1-mutated NSCLC cell lines HCC15 and A427. In both cell lines, LGR6 knockdown inhibited cell growth. LGR6 expression was upregulated in spheroids compared to adherent cultures of A427 cells, suggesting that LGR6 participates in the acquisition of cancer stem cell properties. Immunohistochemical analysis of lung cancer specimens revealed that the LGR6 protein was predominantly overexpressed in SCLCs, large cell neuroendocrine carcinomas, and lung adenocarcinomas, wherein LGR6 overexpression was associated with vascular invasion, the wild-type EGFR genotype, and an unfavorable prognosis. Integrated mRNA sequencing analysis of HCC15 and A427 cells with or without LGR6 knockdown revealed LGR6-related pathways and genes associated with cancer development and stemness properties.

CONCLUSIONS

Our findings highlight the oncogenic roles of LGR6 overexpression induced by aberrant Wnt/β-catenin signaling in lung cancer.

The Multifaceted Role of Human Dickkopf-3 (DKK-3) in Development, Immune Modulation and Cancer

The human Dickkopf (DKK) family includes four main secreted proteins, DKK-1, DKK-2, DKK-3, and DKK-4, as well as the DKK-3 related protein soggy (Sgy-1 or DKKL1). These glycoproteins play crucial roles in various biological processes, and especially modulation of the Wnt signaling pathway. DKK-3 is distinct, with its multifaceted roles in development, stem cell differentiation and tissue homeostasis. Intriguingly, DKK-3 appears to have immunomodulatory functions and a complex role in cancer, acting as either a tumor suppressor or an oncogene, depending on the context. DKK-3 is a promising diagnostic and therapeutic target that can be modulated by epigenetic reactivation, gene therapy and DKK-3-blocking agents. However, further research is needed to optimize DKK-3-based therapies. In this review, we comprehensively describe the known functions of DKK-3 and highlight the importance of context in understanding and exploiting its roles in health and disease.

KLC1-ROS1 Fusion Exerts Oncogenic Properties of Glioma Cells via Specific Activation of JAK-STAT Pathway

Here, we investigated the detailed molecular oncogenic mechanisms of a novel receptor tyrosine kinase (RTK) fusion, KLC1-ROS1, with an adapter molecule, KLC1, and an RTK, ROS1, discovered in pediatric glioma, and we explored a novel therapeutic target for glioma that possesses oncogenic RTK fusion. When wild-type ROS1 and KLC1-ROS1 fusions were stably expressed in the human glioma cell lines A172 and U343MG, immunoblotting revealed that KLC1-ROS1 fusion specifically activated the JAK2-STAT3 pathway, a major RTK downstream signaling pathway, when compared with wild-type ROS1. Immunoprecipitation of the fractionated cell lysates revealed a more abundant association of the KLC1-ROS1 fusion with JAK2 than that observed for wild-type ROS1 in the cytosolic fraction. A mutagenesis study of the KLC1-ROS1 fusion protein demonstrated the fundamental roles of both the KLC1 and ROS1 domains in the constitutive activation of KLC1-ROS1 fusion. Additionally, in vitro assays demonstrated that KLC1-ROS1 fusion upregulated cell proliferation, invasion, and chemoresistance when compared to wild-type ROS1. Combination treatment with the chemotherapeutic agent temozolomide and an inhibitor of ROS1, JAK2, or a downstream target of STAT3, demonstrated antitumor effects against KLC1-ROS1 fusion-expressing glioma cells. Our results demonstrate that KLC1-ROS1 fusion exerts oncogenic activity through serum-independent constitutive activation, resulting in specific activation of the JAK-STAT pathway. Our data suggested that molecules other than RTKs may serve as novel therapeutic targets for RTK fusion in gliomas.

Gene signatures associated with prognosis and chemotherapy resistance in glioblastoma treated with temozolomide

Background: Glioblastoma (GBM) prognosis remains extremely poor despite standard treatment that includes temozolomide (TMZ) chemotherapy. To discover new GBM drug targets and biomarkers, genes signatures associated with survival and TMZ resistance in GBM patients treated with TMZ were identified. Methods: GBM cases in The Cancer Genome Atlas who received TMZ (n = 221) were stratified into subgroups that differed by median overall survival (mOS) using network-based stratification to cluster patients whose somatic mutations affected genes in similar modules of a gene interaction network. Gene signatures formed from differentially mutated genes in the subgroup with the longest mOS were used to confirm their association with survival and TMZ resistance in independent datasets. Somatic mutations in these genes also were assessed for an association with OS in an independent group of 37 GBM cases. Results: Among the four subgroups identified, subgroup four (n = 71 subjects) exhibited the longest mOS at 18.3 months (95% confidence interval: 16.2, 34.1; p = 0.0324). Subsets of the 86 genes that were differentially mutated in this subgroup formed 20-gene and 8-gene signatures that predicted OS in two independent datasets (Spearman's rho of 0.64 and 0.58 between actual and predicted OS; p < 0.001). Patients with mutations in five of the 86 genes had longer OS in a small, independent sample of 37 GBM cases, but this association did not reach statistical significance (p = 0.07). Thirty-one of the 86 genes formed signatures that distinguished TMZ-resistant GBM samples from controls in three independent datasets (area under the curve ≥ 0.75). The prognostic and TMZ-resistance signatures had eight genes in common (ANG, BACH1, CDKN2C, HMGA1, IFI16, PADI4, SDF4, and TP53INP1). The latter three genes have not been associated with GBM previously. Conclusion: PADI4, SDF4, and TP53INP1 are novel therapy and biomarker candidates for GBM. Further investigation of their oncologic functions may provide new insight into GBM treatment resistance mechanisms.

Ca2+ Signaling and Src Functions in Tumor Cells

Signaling by calcium ion (Ca2+) plays a prominent role in cell physiology, and these mechanisms are frequently altered in tumor cells. In this review, we consider the interplay of Ca2+ signaling and the functions of the proto-oncogene non-receptor tyrosine kinase c-Src in tumor cells, and the viral oncogenic variant v-Src in transformed cells. Also, other members of the Src-family kinases are considered in this context. The role of Ca2+ in the cell is frequently mediated by Ca2+-binding proteins, where the Ca2+-sensor protein calmodulin (CaM) plays a prominent, essential role in many cellular signaling pathways. Thus, we cover the available information on the role and direct interaction of CaM with c-Src and v-Src in cancerous cells, the phosphorylation of CaM by v-Src/c-Src, and the actions of different CaM-regulated Ser/Thr-protein kinases and the CaM-dependent phosphatase calcineurin on v-Src/c-Src. Finally, we mention some clinical implications of these systems to identify mechanisms that could be targeted for the therapeutic treatment of human cancers.

Cyclosporin A inhibits prostate cancer growth through suppression of E2F8 transcription factor in a MELK‑dependent manner

The treatment of advanced prostate cancer remains a formidable challenge due to the limited availability of effective treatment options. Therefore, it is imperative to identify promising druggable targets that provide substantial clinical benefits and to develop effective treatment strategies to overcome therapeutic resistance. Cyclosporin A (CsA) showed an anticancer effect on prostate cancer in cultured cell and xenograft models. E2F8 was identified as a master transcription factor that regulated a clinically significant CsA specific gene signature. The expression of E2F8 increased during prostate cancer progression and high levels of E2F8 expression are associated with a poor prognosis in patients with prostate cancer. MELK was identified as a crucial upstream regulator of E2F8 expression through the transcriptional regulatory network and Bayesian network analyses. Knockdown of E2F8 or MELK inhibited cell growth and colony formation in prostate cancer cells. High expression levels of E2F8 and androgen receptor (AR) are associated with a worse prognosis in patients with prostate cancer compared with low levels of both genes. The inhibition of E2F8 improved the response to AR blockade therapy. These results suggested that CsA has potential as an effective anticancer treatment for prostate cancer, while also revealing the oncogenic role of E2F8 and its association with clinical outcomes in prostate cancer. These results provided valuable insight into the development of therapeutic and diagnostic approaches for prostate cancer.

Emerging roles of activating transcription factor 2 in the development of breast cancer: a comprehensive review

Activating transcription factor 2 (ATF2) is a member of the leucine zipper family of DNA binding proteins that are responsible for regulating various genes that play an essential role in major biological and cellular functions. Since ATF2 plays a vital role in cellular proliferation and apoptosis, it is believed that it greatly affects the development of breast cancers. However, its exact role in breast cancer is incompletely understood. It remains a subject of debate, ambiguity, and continuous research. Several studies have suggested the role of ATF2 as an oncogene, promoting cellular proliferation and worsening the outcome of cancers. In contrast, other studies have postulated that ATF2 plays a tumor suppressive role in estrogen receptor-positive breast cancer. The ambiguity surrounding its role in breast cancer is the reason why there is an influx of recent studies and research in this area. In this narrative review, we investigate several studies that have been published about the role of ATF2 in breast cancer. We also explore studies that have examined the association between ATF2 and endocrine therapy resistance. ATF2 has been suggested to modulate estrogen receptor (ER) expression and activity, potentially affecting tamoxifen sensitivity in breast cancer cells. Therefore, the role of ATF2 in DNA repair mechanisms and drug resistance has been deeply explored in this review. Additionally, there are numerous ongoing clinical trials exploring the effect of targeting ATF2 pathways and mechanisms on the outcome of breast cancers, some of which we have discussed. The studies and clinical trials that are being conducted to understand the multifaceted role of ATF2 and its signaling pathways may provide valuable insight for developing efficient targeted therapeutic solutions to enhance the outcomes of breast cancer and overcome endocrine resistance. We suggest further research to elucidate the dual roles of ATF2 in breast cancer and potential therapeutic therapies for its treatment.

Overexpression of POFUT1 promotes malignant phenotype and mediates perineural invasion in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is one of the most aggressive neoplasms, which requires more effective prevention and treatment modalities. Previous studies found that protein O-fucosyltransferase 1 (POFUT1) upregulation promotes carcinogenesis, although the potential roles, underlying molecular mechanisms, and biological implications of POFUT1 in HNSCC were not investigated. In this study, in silico analyses referred POFUT1 as a potential oncogene in HNSCC. Further analysis of tumor and normal tissue samples as well as HNSCC cells with quantitative real-time polymerase chain reaction, Western blot analysis, and immunohistochemistry showed significant overexpression of POFUT1 in HNSCC clinical tumor tissue specimens and cell lines compared to corresponding controls. In vitro investigations revealed that overexpression of POFUT1 promoted phenotypes associated with cancer aggressiveness and its knockdown in HNSCC cells suppressed those phenotypes. Further xenograft experiments demonstrated that POFUT1 is an oncogene in vivo for HNSCC. Immunohistochemical analysis with human clinical samples and cancer cell-dorsal root ganglion ex-vivo coculture model showed that deregulation of POFUT1 is involved in the perineural invasion of HNSCC cells. These results suggest POFUT1 expression as a potential prognostic marker for patients with head and neck cancer and highlight its potential as a target for HNSCC therapy, although more molecular clues are needed to better define the functions of POFUT1 related to HNSCC carcinogenesis.

Protumorigenic role of the atypical cadherin FAT1 by the suppression of PDCD10 via RelA/miR221-3p/222-3p axis in glioblastoma

The atypical cadherin FAT1 function either as a pro or antitumorigenic in tumors of different tissue origins. Our group previously demonstrated the protumorigenic nature of FAT1 signaling in glioblastoma (GBM). In this study, we investigated how FAT1 influences the expression of clustered oncomiRs (miR-221-3p/miR-222-3p) and their downstream effects in GBM. Through several experiments involving the measurement of specific gene/microRNA expression, gene knockdowns, protein and cellular assays, we have demonstrated a novel oncogenic signaling pathway mediated by FAT1 in glioma. These results have been verified using antimiRs and miR-mimic assays. Initially, in glioma-derived cell lines (U87MG and LN229), we observed FAT1 as a novel up-regulator of the transcription factor NFκB-RelA. RelA then promotes the expression of the clustered-oncomiRs, miR-221-3p/miR-222-3p, which in turn suppresses the expression of the tumor suppressor gene (TSG), PDCD10 (Programmed cell death protein10). The suppression of PDCD10, and other known TSG targets (PTEN/PUMA), by miR-221-3p/miR-222-3p, leads to increased clonogenicity, migration, and invasion of glioma cells. Consistent with our in-vitro findings, we observed a positive expression correlation of FAT1 and miR-221-3p, and an inverse correlation of FAT1 and the miR-targets (PDCD10/PTEN/PUMA), in GBM tissue-samples. These findings were also supported by publicly available GBM databases (The Cancer Genome Atlas [TCGA] and The Repository of Molecular Brain Neoplasia Data [Rembrandt]). Patients with tumors displaying high levels of FAT1 and miR-221-3p expression (50% and 65% respectively) experienced shorter overall survival. Similar results were observed in the TCGA-GBM database. Thus, our findings show a novel FAT1/RelA/miR-221/miR-222 oncogenic-effector pathway that downregulates the TSG, PDCD10, in GBM, which could be targeted therapeutically in a specific manner.

From cultivation to cancer: formation of N-nitrosamines and other carcinogens in smokeless tobacco and their mutagenic implications

Tobacco use is a major cause of preventable morbidity and mortality globally. Tobacco products, including smokeless tobacco (ST), generally contain tobacco-specific N-nitrosamines (TSNAs), such as N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-butanone (NNK), which are potent carcinogens that cause mutations in critical genes in human DNA. This review covers the series of biochemical and chemical transformations, related to TSNAs, leading from tobacco cultivation to cancer initiation. A key aim of this review is to provide a greater understanding of TSNAs: their precursors, the microbial and chemical mechanisms that contribute to their formation in ST, their mutagenicity leading to cancer due to ST use, and potential means of lowering TSNA levels in tobacco products. TSNAs are not present in harvested tobacco but can form due to nitrosating agents reacting with tobacco alkaloids present in tobacco during certain types of curing. TSNAs can also form during or following ST production when certain microorganisms perform nitrate metabolism, with dissimilatory nitrate reductases converting nitrate to nitrite that is then released into tobacco and reacts chemically with tobacco alkaloids. When ST usage occurs, TSNAs are absorbed and metabolized to reactive compounds that form DNA adducts leading to mutations in critical target genes, including the RAS oncogenes and the p53 tumor suppressor gene. DNA repair mechanisms remove most adducts induced by carcinogens, thus preventing many but not all mutations. Lastly, because TSNAs and other agents cause cancer, previously documented strategies for lowering their levels in ST products are discussed, including using tobacco with lower nornicotine levels, pasteurization and other means of eliminating microorganisms, omitting fermentation and fire-curing, refrigerating ST products, and including nitrite scavenging chemicals as ST ingredients.

Langerhans cell histiocytosis: current advances in molecular pathogenesis

Langerhans cell histiocytosis (LCH) is a rare and clinically heterogeneous hematological disease characterized by the accumulation of mononuclear phagocytes in various tissues and organs. LCH is often characterized by activating mutations of the mitogen-activated protein kinase (MAPK) pathway with BRAFV600E being the most recurrent mutation. Although this discovery has greatly helped in understanding the disease and in developing better investigational tools, the process of malignant transformation and the cell of origin are still not fully understood. In this review, we focus on the newest updates regarding the molecular pathogenesis of LCH and novel suggested pathways with treatment potential.

FAM111B Acts as an Oncogene in Bladder Cancer

Bladder cancer (BLCA) is a prevalent malignancy of the urinary system, associated with a high recurrence rate and poor prognosis. FAM111B, which encodes a protein containing a trypsin-like cysteine/serine peptidase domain, has been implicated in the progression of various human cancers; however, its involvement in BLCA remains unclear. In this study, we investigated the expression of FAM111B gene in tumor tissues compared to para-tumor tissues using immunohistochemistry and observed a significantly higher FAM111B gene expression in tumor tissues. Furthermore, analysis of clinical characteristics indicated that the increased FAM111B gene expression correlated with lymphatic metastasis and reduced overall survival. To investigate its functional role, we employed FAM111B-knockdown BLCA cell models and performed cell proliferation, wound-healing, transwell, and flow cytometry assays. The results showed that decreased FAM111B gene expression inhibited proliferation and migration but induced apoptosis in BLCA cells. In vivo experiments further validated that FAM111B knockdown suppressed tumor growth. Overall, our findings suggest that FAM111B acts as an oncogene in BLCA, playing a critical role in tumorigenesis, progression, and metastasis of BLCA. In conclusion, we have demonstrated a strong correlation between the expression of FAM111B gene and the development, progression, and metastasis of bladder cancer (BLCA). Thus, FAM111B is an oncogene associated with BLCA and holds promise as a molecular target for future treatment of this cancer.

Human tumor viruses: induction of three-dimensional alterations in the host genome structure

Certain viruses called tumor viruses or oncoviruses are capable to change the gene expression pattern of distinct human or animal cell types in tissue culture, resulting in uncontrolled proliferation as well as a change in the social behavior of the infected cells: the oncovirus-transformed, immortalized cells are capable to form malignant neoplasms in suitable animal models. At present, seven human viruses are categorized as causative agents of distinct human malignancies. The genomes of human tumor viruses, typically encode viral oncoproteins and non- translated viral RNAs that affect the gene expression pattern of their target cells or induce genetic and epigenetic alterations contributing to oncogenesis. Recently, the application of chromatin conformation capture technologies and three-dimensional (3D) molecular imaging techniques revealed how the gene products or genomes of certain human tumor viruses interact with and induce alterations in the 3D host genome structure. This Mini Review aims to cover selected aspects of these developments. The papers, discussed briefly, describe how insertion of a novel viral binding site for the 3D genome organizer cellular protein CCCTC-binding factor (CTCF) into the DNA of T cells infected by human T-cell lymphotropic virus type 1 (HTLV-1) may contribute to lymphomagenesis, as well as how integration of high risk human papillomavirus genome into the host cell DNA may facilitate cervical carcinogenesis. Recent results regarding the interactions of cellular genomes with the episomal, chromatinized DNA genomes of oncogenic human herpesvirus, Epstein-Barr virus (EBV) will also be summarized, similarly to available data regarding contacts formed by episomal or integrated hepatitis B virus (HBV) DNA with host chromatin. Finally, a putative mechanism of hepatitis C virus (HCV) induced chromatin alterations will be presented, which may solve the riddle, how a cytoplasmic RNA virus without a viral oncogene could induce malingnant transfrormation of hepatocytes.

Hyperactive Ras disrupts cell size control and a key step in cell cycle entry in budding yeast

Severe defects in cell size are a nearly universal feature of cancer cells. However, the underlying causes are unknown. A previous study suggested that a hyperactive mutant of yeast Ras (ras2G19V) that is analogous to the human Ras oncogene causes cell size defects, which could provide clues to how oncogenes influence cell size. However, the mechanisms by which ras2G19V influences cell size are unknown. Here, we found that ras2G19V inhibits a critical step in cell cycle entry, in which an early G1 phase cyclin induces transcription of late G1 phase cyclins. Thus, ras2G19V drives overexpression of the early G1 phase cyclin Cln3, yet Cln3 fails to induce normal transcription of late G1 phase cyclins, leading to delayed cell cycle entry and increased cell size. ras2G19V influences transcription of late G1 phase cyclins via a poorly understood step in which Cln3 inactivates the Whi5 transcriptional repressor. Previous studies found that yeast Ras relays signals via protein kinase A (PKA); however, ras2G19V appears to influence late G1 phase cyclin expression via novel PKA-independent signaling mechanisms. Together, the data define new mechanisms by which hyperactive Ras influences cell cycle entry and cell size in yeast. Hyperactive Ras also influences expression of G1 phase cyclins in mammalian cells, but the mechanisms remain unclear. Further analysis of Ras signaling in yeast could lead to discovery of new mechanisms by which Ras family members control expression of G1 phase cyclins.

The oncogenic potential of Rab-like protein 1A (RBEL1A) GTPase: The first review of RBEL1A research with future research directions and challenges

Research on Rab-like protein 1A (RBEL1A) in the past two decades highlighted the oncogenic properties of this gene. Despite the emerging evidence, its importance in cancer biology was underrated. This is the first RBEL1A critical review covering its discovery, biochemistry, physiological functions, and clinical insights. RBEL1A expression at the appropriate levels appears essential in normal cells and tissues to maintain chromosomal stability; however, its overexpression is linked to tumorigenesis. Furthermore, the upstream and downstream targets of the RBEL1A signaling pathways will be discussed. Mechanistically, RBEL1A promotes cell proliferation signals by enhancing the Erk1/2, Akt, c-Myc, and CDK pathways while blunting the apoptotic signals via inhibitions on p53, Rb, and caspase pathways. More importantly, this review covers the clinical relevance of RBEL1A in the cancer field, such as drug resistance and poor overall survival rate. Also, this review points out the bottle-necks of the RBEL1A research and its future research directions. It is becoming clear that RBEL1A could potentially serve as a valuable target of anticancer therapy. Genetic and pharmacological researches are expected to facilitate the identification and development of RBEL1A inhibitors as cancer therapeutics in the future, which could undoubtedly improve the management of human malignancy.

The road less traveled: activating an oncogenic kinase

Elevated phosphoinositide 3-kinase (PI3K) activity in human tumors has prompted widespread efforts to develop chemical PI3K inhibitors for oncology indications. In an innovative new study, Gong et al. report the discovery of a highly selective activator of the PI3Kα isoform, with promising activity in assays of nerve regrowth and cardioprotection from ischemia-reperfusion injury (IRI).

Pan-cancer analysis of the oncogenic effects of G-protein-coupled receptor kinase-interacting protein-1 and validation on liver hepatocellular carcinoma

BACKGROUND

Despite G-protein-coupled receptor kinase-interacting protein-1 (GIT1) being recognized as a new promoter gene in some types of cancer, its effect on human pan-cancers and liver hepatocellular carcinoma (LIHC) remains unclear.

OBJECTIVES

To elucidate the molecular mechanisms of GIT1 in pan-cancer and LIHC.

MATERIAL AND METHODS

Various bioinformatics approaches were utilized to elucidate the oncogenic effects of GIT1 on human pan-cancers.

RESULTS

The GIT1 was aberrantly expressed in pan-cancers and associated with the clinical stage. Moreover, the upregulation of GIT1 expression was indicative of poor overall survival (OS) in patients with LIHC, skin cutaneous melanoma (SKCM) and uterine corpus endometrial carcinoma (UCEC), as well as of poor disease-free survival (DFS) in patients with LIHC and UCEC. Furthermore, GIT1 levels were correlated with cancer-associated fibroblasts (CAFs) in adrenocortical carcinoma (ACC), cervical squamous cell carcinoma (CESC) and LIHC. The analysis of single-cell sequencing data revealed an association of GIT1 levels with apoptosis, cell cycle and DNA damage. In addition, multivariate Cox analysis indicated that high GIT1 levels were an independent risk factor for shorter OS in patients with LIHC. Finally, the gene set enrichment analysis revealed INFLAMMATORY_RESPONSE pathway and IL2_STAT5_SIGNALING to be the most enriched in LIHC.

CONCLUSIONS

Our data demonstrate the oncogenic effects of GIT1 on various cancers. We believe that GIT1 can serve as a biomarker for LIHC.

Oncogenic miR-1825 promotes head and neck carcinogenesis via targeting FREM1

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignant cancer type worldwide. Although the therapeutic modalities currently used for patients with HNSCC improved in recent decades, HNSCC prognosis is still poor. Therefore, it is an urgent necessity to understand the pathogenesis of HNSCC, to develop novel and effective treatment strategies, and to characterize and identify the oncogenes that are responsible for an aggressive HNSCC phenotype. In this study, we aimed to better understand the roles of miR-1825 in the pathogenesis of HNSCC. We examined the impacts of miR-1825 deregulation on the cancer-associated phenotypes using in vitro tests evaluating cell viability, clonogenicity, cell migration, invasion, apoptosis, and stem cell characteristics. In addition, we investigated the effects of miR-1825 overexpression on the tumor formation capacity of head and neck cancer cells in vivo using nude mice. We searched for potential targets of miR-1825 using microarray analysis and luciferase assay. We found that miR-1825 expression is upregulated in head and neck cells and clinical tumor samples in comparison to corresponding controls, where it potentially acts as an oncogene. We, then, showed that ectopic miR-1825 overexpression promotes cellular phenotypes related to head and neck cancer progression in vitro and has a stimulating potential on cancer formation in vivo. We also identified FREM1 as a direct target of miR-1825 and demonstrated its reduced expression in HNSCC samples using immunohistochemistry analysis. Collectively, we suggest that the miR-1825/FREM1 axis serves as an important mediator of HNSCC development, where miR-1825 acts as an oncogene.