Lymphatic metastasis-related TBL1XR1 enhances stemness and metastasis in gastric cancer stem-like cells by activating ERK1/2-SOX2 signaling

Gut microbiota-dependent modulation of pre-metastatic niches by Jianpi Yangzheng decoction in the prevention of lung metastasis of gastric cancer

AIM OF THE STUDY

To evaluate the in vitro and in vivo anti-metastasis efficacy of Jianpi Yangzheng (JPYZ) decoction against gastric cancer (GC) and its potential mechanisms.

MATERIALS AND METHODS

The distant metastasis of GC cells administered via tail vein injection was assessed using the pre-metastatic niche (PMN) model. 16S rRNA sequencing and GC-MS/MS were applied to determine the component of the gut microbiota and content of short-chain fatty acids (SCFAs) in feces of mice, respectively. The proportion of myeloid-derived suppressor cells (MDSCs) in the lung was evaluated by flow cytometry and immunofluorescence. Serum or tissue levels of inflammation factors including IL-6, IL-10 and TGF-β were determined by ELISA or Western blot respectively.

RESULTS

Injecting GC cells into the tail vein of mice led to the development of lung metastases and also resulted in alterations in the composition of gut microbiota and the levels of SCFAs produced. Nevertheless, JPYZ treatment robustly impeded the effect of GC cells administration. Mechanically, JPYZ treatment not only prevented the alteration in gut microbiota structure, but also restored the SCFAs content induced by GC cells administration. Specifically, JPYZ treatment recovered the relative abundance of genera Moryella, Helicobacter, Lachnoclostridium, Streptococcus, Tuzzerella, GCA-900066575, uncultured_Lachnospiraceae, Rikenellaceae_RC9_gut_group and uncultured_bacterium_Muribaculaceae to near the normal control levels. In addition, JPYZ abrogated MDSCs accumulation in the lung tissue and blocked inflammation factors overproduction in the serum and lung tissues, which subsequently impede the formation of the immunosuppressive microenvironment. Correlation analysis revealed that the prevalence of Rikenellaceae in the model group exhibited a positive correlation with MDSCs proportion and inflammation factor levels. Conversely, the scarcity of Muribaculaceae in the model group showed a negative correlation with these parameters. This suggests that JPYZ might exert an influence on the gut microbiota and their metabolites, such as SCFAs, potentially regulating the formation of the PMN and consequently impacting the outcome of GC metastasis.

CONCLUSION

These findings suggest that GC cells facilitate metastasis by altering the gut microbiota composition, affecting the production of SCFAs, and recruiting MDSCs to create a pro-inflammatory pre-metastatic niche. JPYZ decoction counteracts this process by reshaping the gut microbiota structure, enhancing SCFA production, and inhibiting the formation of the pre-metastatic microenvironment, thereby exerting an anti-metastatic effect.

Neoadjuvant chemotherapy-induced remodeling of human hormonal receptor-positive breast cancer revealed by single-cell RNA sequencing

Hormone receptor-positive breast cancer (HR+ BC) is known to be relatively insensitive to chemotherapy, and since chemotherapy has remained the major neoadjuvant therapy for HR+ BC, the undetermined mechanism of chemoresistance and how chemotherapy reshapes the immune microenvironment need to be explored by high-throughput technology. By using single-cell RNA sequencing and multiplexed immunofluorescence staining analysis of HR+ BC samples (paired pre- and post-neoadjuvant chemotherapy (NAC)), the levels of previously unrecognized immune cell subsets, including CD8+ T cells with pronounced expression of T-cell development (LMNA) and cytotoxicity (FGFBP2) markers, CD4+ T cells characterized by proliferation marker (ATP1B3) expression and macrophages characterized by CD52 expression, were found to be increased post-NAC, which were predictive of chemosensitivity and their antitumor function was also validated with in vitro experiments. In terms of immune checkpoint expression of CD8+ T cells, we found their changes were inconsistent post-NAC, that LAG3, VSIR were decreased, and PDCD1, HAVCR2, CTLA4, KLRC1 and BTLA were increased. In addition, we have identified novel genomic and transcriptional patterns of chemoresistant cancer cells, both innate and acquired, and have confirmed their prognostic value with TCGA cohorts. By shedding light on the ecosystem of HR+ BC reshaped by chemotherapy, our results uncover valuable candidates for predicting chemosensitivity and overcoming chemoresistance in HR+ BC.

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.

lncRNA799/TBL1XR1/ZEB1 Axis Forms a Feedback Loop to Promote the Epithelial-Mesenchymal Transition of Cervical Cancer Cells

Cervical cancer is a common malignancy among women worldwide. Long non-coding RNAs (lncRNAs) are frequently involved in the pathogenesis of cervical cancer. Therefore, the present study aimed to investigate the potentials of lncRNA799 in cervical cancer. mRNA and protein expression were detected by reverse transcription-quantitative polymerase chain reaction and Western blot analysis, respectively. Cellular functions were assessed using CCK-8, wound healing and transwell analysis. The binding potential of zinc finger E-box-binding homeobox 1 (ZEB1) on the promoter of lncRNA799 was predicted utilizing the JASPAR database, and was then verified by luciferase and chromatin immunoprecipitation (ChIP) assays. Furthermore, the gene interactions were assessed using RNA immunoprecipitation and co-immunoprecipitation assays. The results demonstrated that lncRNA799 was upregulated in cervical cancer cells. However, lncRNA799 deficiency suppressed the proliferation and epithelial-mesenchymal transition of cervical cancer cells. Furthermore, lncRNA799 could interact with eukaryotic translation initiation factor 4A3 to maintain the mRNA stability of transducin (β)-like 1 X-linked receptor 1 (TBL1XR1) and promote the interaction between ZEB1 and TBL1XR1. Additionally, the results showed that ZEB1 could transcriptionally activate lncRNA799. Taken together, the present study suggested that the lncRNA799/TBL1XR1/ZEB1 axis could form a positive feedback loop in cervical cancer and could be, therefore, considered as a potential therapeutic strategy for cervical cancer.

Data-independent acquisition (DIA) mass spectrometry reveals related proteins involved in the occurrence of early intestinal-type gastric cancer

Identifying proteins associated with the onset of early intestinal-type gastric cancer (EIGC) can yield valuable insights into the pathogenesis of this specific subtype of gastric cancer. Data-independent acquisition mass spectroscopy (DIA-MS) was utilized to identify the differential protein between 10 cases of EIGC and atrophic gastritis with intestinal metaplasia (NGC). The expressions of IPO4, TBL1XR1, p62/SQSTM1, PKP3, and CRTAP were verified by immunohistochemistry (IHC) in 20 EIGC samples, 17 gastric low-grade intraepithelial neoplasia (LGIN) samples, and 21 healthy controls. The prognostic values of the five genes were validated in the transcriptome data by survival analysis. A total of 4,028 proteins were identified using DIA-MS and a total of 177 differential proteins were screened with log2(fold change) > 1.5. Among them, 113 proteins were significantly up-regulated, and 64 proteins were significantly down-regulated in EIGC tissues. IHC results showed that proteins IPO4, TBL1XR1, p62/SQSTM1, PKP3, and CRTAP were highly expressed in the cytoplasm of EIGC and LGIN, which was consistent with the results of DIA-MS. Among them, p62/SQSTM1 may undergo nuclear-cytoplasmic transfer. The five protein-coding genes were associated with intestinal-type gastric cancer survival and exhibited differential expression across various disease stages. The study successfully identified differentially expressed proteins between EIGC and NGC, providing potential biomarkers and valuable insights into the mechanism underlying intestinal-type gastric cancer.

Identification of a Novel CD8+ T cell exhaustion-related gene signature for predicting survival in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a major health concern, necessitating a deeper understanding of its prognosis and underlying mechanisms. This study aimed to investigate the mechanism and prognostic value of CD8+ T Cell exhaustion (CD8+ TEX)-related genes in HCC and construct a survival prognosis prediction model for patients with HCC.

METHODS

CD8+ TEX-related genes associated with HCC prognosis were analysed and identified, and a prognostic prediction model was constructed using the 'least absolute shrinkage and selection operator' Cox regression model. Immunohistochemistry was used to verify the expression of the model genes in HCC tissues. A nomogram was constructed based on risk scores and clinical features, and its predictive efficacy was verified. The expression of STAM, ANXA5, and MAD2L2 in HCC cell lines was detected by western blotting; subsequently, these genes were knocked down in HCC cell lines by small interfering RNA, and their effects on the proliferation and migration of HCC cell lines were detected by colony formation assay, cck8, wound healing, and transwell assays.

RESULTS

Six genes related to CD8+ TEX were included in the risk-prediction model. The prognosis of patients with HCC in the low-risk group was significantly better than that of those in the high-risk group. Cox regression analysis revealed that the risk score was an independent risk factor for the prognosis of patients with HCC. The differentially expressed genes in patients with high-risk HCC were mainly enriched in the nucleotide-binding oligomerization domain-containing protein-like receptor, hypoxia-inducible factor-1, and tumour programmed cell death protein (PD)-1/PD-L1 immune checkpoint pathways. The CD8+ TEX-related genes STAM, ANXA5, and MAD2L2 were knocked down in HCC cell lines to significantly inhibit cell proliferation and migration. The prediction results of the nomogram based on the risk score showed a good fit and application value.

CONCLUSION

The prediction model based on CD8+ TEX-related genes can predict the prognosis of HCC and provide a theoretical basis for the early identification of patients with poor HCC prognosis.

miR-199a/214 cluster enhances prostate cancer sensitiveness to nimotuzumab via targeting TBL1XR1

Prostate cancer (PCa) is a significant health concern affecting men worldwide. Previous studies have shown that nimotuzumab, a drug targeting the epidermal growth factor receptor (EGFR), can effectively inhibit cancer progression. Here, we aimed to explore the role of miR-199a/214 cluster in mediating the inhibitory effect of nimotuzumab on the development of PCa. In this study, we conducted an MTT assay to assess cell proliferation and utilized flow cytometry to evaluate cell apoptosis and cell cycle arrest. To investigate the molecular mechanisms underlying the effects of nimotuzumab on prostate cancer development, we focused on the miR-199a-5p and miR-214-3p miRNA clusters. The TargetScan Human database was used to predict the binding sites between miR-199a-5p or miR-214-3p and the 3'-UTR of the transducin (β)-like 1 X-linked receptor 1 (TBL1XR1) mRNA. To confirm the direct interaction and binding between miR-199a-5p or miR-214-3p and the 3'-UTR of TBL1XR1 mRNA, we performed luciferase reporter assays. Our findings demonstrated that nimotuzumab exerted a significant dosage-dependent suppression of PCa cell proliferation and facilitated PCa cell apoptosis and cell cycle arrest. Concurrently, nimotuzumab obviously impeded the activity of Wnt/β-catenin and EGFR signaling pathways in PCa cells. We also observed downregulation of miR-199a-5p and miR-214-3p in PCa cells. Overexpression of miR-199a/214 cluster inhibited PCa cell viability and enhanced cell apoptosis. Furthermore, we found that miR-199a/214 cluster augmented the inhibitory effect of nimotuzumab on PCa cell proliferation and promoted its ability to induce apoptosis and cell cycle arrest. This effect was reversed upon TBL1XR1 overexpression, indicating that TBL1XR1 is involved in the regulatory pathway of miR-199a/214 and nimotuzumab in PCa cells. We further revealed that TBL1XR1 was overexpressed in PCa and was identified as a downstream target of the miR-199a/214 cluster. In nimotuzumab-treated PCa cells, the overexpression of miR-199a/214 markedly inhibited Wnt/β-catenin and EGFR signaling, and this effect was also rescued by TBL1XR1 overexpression. In summary, our data indicated that miR-199a/214 cluster play a crucial role in enhancing the inhibitory effect of nimotuzumab on PCa development by downregulating TBL1XR1 and modulating Wnt/β-catenin and EGFR signaling pathways. These findings offer a novel therapeutic approach for the treatment of prostate cancer.

FTO Promotes the Stemness of Gastric Cancer Cells

The full name of the FTO gene is fat mass and obesity-associated gene. In recent years, it has also been found that FTO is involved in m6A demethylation and regulates the progression of multiple cancers, including gastric cancer. The cancer stem cell theory argues that cancer stem cells are key factors in cancer metastasis, and inhibiting the expression of stemness genes is a good method to inhibit metastasis of gastric cancer. Currently, the role of the FTO gene in regulating stemness of gastric cancer cells is still unclear. By analyzing public databases, it was discovered that FTO gene expression was increased in gastric cancer, and high expression of FTO was associated with poor prognosis of patients with gastric cancer. After gastric cancer stem cells were isolated, it was found that FTO protein expression was increased in gastric cancer stem cells; stemness of gastric cancer cells was reduced after the FTO gene knockdown; subcutaneous tumors of nude mice were smaller than those of the control group after FTO knockdown; and stemness of gastric cancer cells was enhanced after FTO was overexpressed by plasmid. By reviewing additional literature and experimental validation, we found that SOX2 may be the factor by which FTO promotes the stemness of gastric cancer cells. Therefore, it was concluded that FTO could promote the stemness of gastric cancer cells, and targeting FTO may be a potential therapeutic approach for patients with metastatic gastric cancer. CTR number: TOP-IACUC-2021-0123.

SOX2-associated signaling pathways regulate biological phenotypes of cancers

SOX2 is a transcription factor involved in multiple stages of embryonic development. In related reports, SOX2 was found to be abnormally expressed in tumor tissues and correlated with clinical features such as TNM staging, tumor grade, and prognosis in patients with various cancer types. In most cancer types, SOX2 is a tumor-promoting factor that regulates tumor progression and metastasis primarily by maintaining the stemness of cancer cells. In addition, SOX2 also regulates the proliferation, apoptosis, invasion, migration, ferroptosis and drug resistance of cancer cells. However, SOX2 acts as a tumor suppressor in some cases in certain cancer types, such as gastric and lung cancer. These key regulatory functions of SOX2 involve complex regulatory networks, including protein-protein and protein-nucleic acid interactions through signaling pathways and noncoding RNA interactions, modulating SOX2 expression may be a potential therapeutic strategy for clinical cancer patients. Therefore, we sorted out the phenotypes related to SOX2 in cancer, hoping to provide a basis for further clinical translation.

AKAP8L enhances the stemness and chemoresistance of gastric cancer cells by stabilizing SCD1 mRNA

Gastric cancer (GC) remains the third leading cause of cancer-related deaths. Chemoresistance is the major determinant of GC treatment failure. To explore the molecular mechanisms of GC chemoresistance, mass spectrometry was performed to detect the genes altered in expression between chemoresistant and chemosensitive GC. PRKA kinase anchor protein 8L (AKAP-8L) was identified as one of the top upregulated genes in chemoresistant GC tissues. Moreover, the higher AKAP-8L expression was associated with the lower survival rate in GC patients. Overexpression of AKAP-8L enhanced the GC cell stemness and chemoresistance of oxaliplatin in vivo and in vitro. AKAP-8L deficiency obtained the opposite results. Mechanistically, AKAP-8L interacted with Stearoyl-CoA desaturase 1 (SCD1) mRNA and IGF2BP1 protein, and regulated SCD1 mRNA stability via IGF2BP1-dependent manner. SCD1 played a critical role in mediating the function of AKAP-8L in GC cell stemness and chemoresistance. Clinically, AKAP-8L and SCD1 protein levels was positively associated with human GC chemoresistance. Taken together, our results demonstrated that AKAP-8L facilitates GC chemoresistance via regulating SCD1-mediated stemness of GC cells. AKAP8L may represent a novel therapeutic target to overcome GC chemoresistance.

Targeting Gastric Cancer Stem Cells to Enhance Treatment Response

Gastric cancer (GC) was the fourth deadliest cancer in the world in 2020, and about 770,000 people died from GC that year. The death of patients with GC is mainly caused by the metastasis, recurrence, and chemotherapy resistance of GC cells. The cancer stem cell theory defines cancer stem cells (CSCs) as a key factor in the metastasis, recurrence, and chemotherapy resistance of cancer. It considers targeting gastric cancer stem cells (GCSCs) to be an effective method for the treatment of GC. For GCSCs, genes or noncoding RNAs are important regulatory factors. Many experimental studies have found that some drugs can target the stemness of gastric cancer by regulating these genes or noncoding RNAs, which may bring new directions for the clinical treatment of gastric cancer. Therefore, this review mainly discusses related genes or noncoding RNAs in GCSCs and drugs that target its stemness, thereby providing some information for the treatment of GC.

Dicer-mediated miR-200b expression contributes to cell migratory/invasive abilities and cancer stem cells properties of breast cancer cells

Distant metastasis is the leading cause of death in patients with breast cancer. Despite considerable treatment advances, the clinical outcomes of patients with metastatic breast cancer remain poor. CSCs can self-renew, enhancing cancer progression and metastasis. Dicer, a microRNA (miRNA) processing–related enzyme, is required for miRNA maturation. Imbalanced Dicer expression may be pivotal in cancer progression. However, whether and how Dicer affects the stemness of metastatic breast cancer cells remains unclear. Here, we hypothesized that Dicer regulates the migration, invasion, and stemness of breast cancer cells. We established highly invasive cell lines (MCF-7/I-3 and MDA-MB-231/I-3) and observed that Dicer expression was conspicuously lower in the highly invasive cells than in the parental cells. The silencing of Dicer significantly enhanced the cell migratory/invasive abilities and CSCs properties of the breast cancer cells. Conversely, the overexpression of Dicer in the highly invasive cells reduced their migration, invasion, and CSCs properties. Our bioinformatics analyses demonstrated that low Dicer levels were correlated with increased breast cancer risk. Suppression of Dicer inhibited miR-200b expression, whereas miR-200b suppression recovered Dicer knockdown–induced migration, invasion, and cancer stem cells (CSCs) properties of the breast cancer cells. Thus, our findings reveal that Dicer is a crucial regulator of the migration, invasion, and CSCs properties of breast cancer cells and is significantly associated with poor survival in patients with breast cancer.

An animal model for Pierpont syndrome; a mouse bearing the Tbl1xr1Y446C/Y446C mutation

Pierpont syndrome is a rare disorder characterized mainly by global developmental delay, unusual facial features, altered fat distribution in the limbs and hearing loss. A specific mutation (p.Tyr446Cys) in TBL1XR1, encoding a WD40 repeat-containing protein, which is a component of the SMRT/NCoR (silencing mediator retinoid and thyroid hormone receptors/nuclear receptor corepressors), has been reported as the genetic cause of Pierpont syndrome. Here, we used CRISPR-cas9 technology to generate a mutant mouse with the Y446C mutation in Tbl1xr1, which is also present in Pierpont syndrome. Several aspects of the phenotype were studied in the mutant mice: growth, body composition, hearing, motor behavior, thyroid hormone state and lipid and glucose metabolism. The mutant mice (Tbl1xr1^Y446C/Y446C) displayed delayed growth, altered body composition with increased relative lean mass and impaired hearing. Expression of several genes involved in fatty acid metabolism differed in white adipose tissue, but not in liver or muscle of mutant mice compared to wild-type mice (Tbl1xr1^+/+). No difference in thyroid hormone plasma concentrations was observed. Tbl1xr1^Y446C/Y446C mice can be used as a model for distinct features of Pierpont syndrome, which will enable future studies on the pathogenic mechanisms underlying the various phenotypic characteristics.

A Network Pharmacology Perspective Investigation of the Pharmacological Mechanisms of the Herbal Drug FDY003 in Gastric Cancer

Gastric cancer (GC) is one of the most common and deadly malignant tumors worldwide. While the application of herbal drugs for GC treatment is increasing, the multicompound–multitarget pharmacological mechanisms involved are yet to be elucidated. By adopting a network pharmacology strategy, we investigated the properties of the anticancer herbal drug FDY003 against GC. We found that FDY003 reduced the viability of human GC cells and enhanced their chemosensitivity. We also identified 8 active phytochemical compounds in FDY003 that target 70 GC-associated genes and proteins. Gene ontology (GO) enrichment analysis suggested that the targets of FDY003 are involved in various cellular processes, such as cellular proliferation, survival, and death. We further identified various major FDY003 target GC-associated pathways, including PIK3-Akt, MAPK, Ras, HIF-1, ErbB, and p53 pathways. Taken together, the overall analysis presents insight at the systems level into the pharmacological activity of FDY003 against GC.

MicroRNAs regulating SOX2 in cancer progression and therapy response

The proliferation, metastasis and therapy response of tumour cells are tightly regulated by interaction among various signalling networks. The microRNAs (miRNAs) can bind to 3'-UTR of mRNA and down-regulate expression of target gene. The miRNAs target various molecular pathways in regulating biological events such as apoptosis, differentiation, angiogenesis and migration. The aberrant expression of miRNAs occurs in cancers and they have both tumour-suppressor and tumour-promoting functions. On the contrary, SOX proteins are capable of binding to DNA and regulating gene expression. SOX2 is a well-known member of SOX family that its overexpression in different cancers to ensure progression and stemness. The present review focuses on modulatory impact of miRNAs on SOX2 in affecting growth, migration and therapy response of cancers. The lncRNAs and circRNAs can function as upstream mediators of miRNA/SOX2 axis in cancers. In addition, NF-κB, TNF-α and SOX17 are among other molecular pathways regulating miRNA/SOX2 axis in cancer. Noteworthy, anti-cancer compounds including bufalin and ovatodiolide are suggested to regulate miRNA/SOX2 axis in cancers. The translation of current findings to clinical course can pave the way to effective treatment of cancer patients and improve their prognosis.

Characterization of gastric cancer stem-like molecular features, immune and pharmacogenomic landscapes

Cancer stem cells (CSCs) actively reprogram their tumor microenvironment (TME) to sustain a supportive niche, which may have a dramatic impact on prognosis and immunotherapy. However, our knowledge of the landscape of the gastric cancer stem-like cell (GCSC) microenvironment needs to be further improved. A multi-step process of machine learning approaches was performed to develop and validate the prognostic and predictive potential of the GCSC-related score (GCScore). The high GCScore subgroup was not only associated with stem cell characteristics, but also with a potential immune escape mechanism. Furthermore, we experimentally demonstrated the upregulated infiltration of CD206+ tumor-associated macrophages (TAMs) in the invasive margin region, which in turn maintained the stem cell properties of tumor cells. Finally, we proposed that the GCScore showed a robust capacity for prediction for immunotherapy, and investigated potential therapeutic targets and compounds for patients with a high GCScore. The results indicate that the proposed GCScore can be a promising predictor of prognosis and responses to immunotherapy, which provides new strategies for the precision treatment of GCSCs.

3q26 Amplifications in Cervical Squamous Carcinomas

Background: Squamous carcinomas of the uterine cervix often carry mutations of the gene encoding for the catalytic sub-unit of kinase PI3K, PIK3CA. The locus of this gene at chromosome 3q26 and neighboring loci are also commonly amplified. The landscape of 3q26-amplified cases have not been previously characterized in detail in cervical cancer. Methods: Published genomic data and associated clinical data from TCGA cervical cancer cohort were analyzed at cBioportal for amplifications in genes at 3q26. The clinical and molecular characteristics of the group of patients with 3q26 amplifications was compared with the group without 3q26 amplifications. Comparative prevalence of amplification and expression of genes at 3q26 in amplified squamous cervical cancer cases were surveyed as well as 3q26 amplifications in cervical cancer cell line databases. Results: Amplification of 3q26 locus is a prevalent molecular lesion in cervical squamous cell carcinomas encountered in about 15% of cases in TCGA cohort of 247 patients. Cancer-related genes commonly amplified from 3q26 include PIK3CA, TBL1XR1, DCUN1D1, SOX2, MECOM, PRKCI, and TERC. Amplified cases do not completely overlap with PIK3CA mutant cases. Differences exist between 3q26-amplified and non-amplified carcinomas in the frequency of mutations and frequency of other amplifications. Most commonly over-expressed genes in 3q26 amplified cases include PIK3CA, TBL1XR1, DCUN1D1, and less commonly SOX2 and PRKCI. Conclusion: The subset of squamous cervical carcinomas with 3q26 amplifications is not overlapping with cancers carrying PIK3CA mutations and contains, besides PIK3CA, other cancer-associated genes that are over-expressed at the mRNA level, including TBL1XR1 and DCUN1D1. DCUN1D1, a regulator of SCF ubiquitin ligase activity, may be a relevant pathogenic player given the importance of ubiquitination and the proteasome in the disease. These observations could form the basis for therapeutic exploitation in this subset of squamous cervical carcinomas.