IQGAP1 modulates the proliferation and invasion of thyroid cancer cells in response to estrogen

Deciphering the SOX4/MAPK1 regulatory axis: a phosphoproteomic insight into IQGAP1 phosphorylation and pancreatic Cancer progression

OBJECTIVE

This study aims to elucidate the functional role of IQGAP1 phosphorylation modification mediated by the SOX4/MAPK1 regulatory axis in developing pancreatic cancer through phosphoproteomics analysis.

METHODS

Proteomics and phosphoproteomics data of pancreatic cancer were obtained from the Clinical Proteomic Tumor Analysis Consortium (CPTAC) database. Differential analysis, kinase-substrate enrichment analysis (KSEA), and independent prognosis analysis were performed on these datasets. Subtype analysis of pancreatic cancer patients was conducted based on the expression of prognostic-related proteins, and the prognosis of different subtypes was evaluated through prognosis analysis. Differential analysis of proteins in different subtypes was performed to identify differential proteins in the high-risk subtype. Clinical correlation analysis was conducted based on the expression of prognostic-related proteins, pancreatic cancer typing results, and clinical characteristics in the pancreatic cancer proteomics dataset. Functional pathway enrichment analysis was performed using GSEA/GO/KEGG, and most module proteins correlated with pancreatic cancer were selected using WGCNA analysis. In cell experiments, pancreatic cancer cells were grouped, and the expression levels of SOX4, MAPK1, and the phosphorylation level of IQGAP1 were detected by RT-qPCR and Western blot experiments. The effect of SOX4 on MAPK1 promoter transcriptional activity was assessed using a dual-luciferase assay, and the enrichment of SOX4 on the MAPK1 promoter was examined using a ChIP assay. The proliferation, migration, and invasion functions of grouped pancreatic cancer cells were assessed using CCK-8, colony formation, and Transwell assays. In animal experiments, the impact of SOX4 on tumor growth and metastasis through the regulation of MAPK1-IQGAP1 phosphorylation modification was studied by constructing subcutaneous and orthotopic pancreatic cancer xenograft models, as well as a liver metastasis model in nude mice.

RESULTS

Phosphoproteomics and proteomics data analysis revealed that the kinase MAPK1 may play an important role in pancreatic cancer progression by promoting IQGAP1 phosphorylation modification. Proteomics analysis classified pancreatic cancer patients into two subtypes, C1 and C2, where the high-risk C2 subtype was associated with poor prognosis, malignant tumor typing, and enriched tumor-related pathways. SOX4 may promote the occurrence of the high-risk C2 subtype of pancreatic cancer by regulating MAPK1-IQGAP1 phosphorylation modification. In vitro cell experiments confirmed that SOX4 promoted IQGAP1 phosphorylation modification by activating MAPK1 transcription while silencing SOX4 inhibited the proliferation, migration, and invasion of pancreatic cancer cells by reducing the phosphorylation level of MAPK1-IQGAP1. In vivo, animal experiments further confirmed that silencing SOX4 suppressed the growth and metastasis of pancreatic cancer by reducing the phosphorylation level of MAPK1-IQGAP1.

CONCLUSION

The findings of this study suggest that SOX4 promotes the phosphorylation modification of IQGAP1 by activating MAPK1 transcription, thereby facilitating the growth and metastasis of pancreatic cancer.

Improved antioxidant and anti-tubercular potential of liquiritigenin grafted on low molecular weight chitosan from gladius of Sepioteuthis lessoniana

Chitosan (CH) is natural abundant biopolymer present on earth after cellulose. CH can be functionalized by numerous functional groups such as amino and carboxyl groups, potential biologically active compounds. The functionalization of CH with polyphenols had a greater biological than non-grafted CH. In the present study, the polyphenolic compound liquiritigenin (LTG) is chemically functionalized on the low molecular weight chitosan (LMW-CH) (693.09 Da). This was extracted and irradiated with gamma radiation from the gladius of Sepioteuthis lessoniana. The grafted compound was to in vitro anti-oxidant employing physicochemical methods and characterization was made by spectroscopic methods. The degree of deacetylation (DDA) of the LMW-CH was detected in 74 % of the samples, and at higher concentrations (100 g/mL). LMW-CH grafted with LTG had improved water solubility (5 mg/mL), and was thermally stable upto 143.58 °C. Its molecular weight was 855.1 Da. In conclusion the in vitro antioxidant and the anti-tuberculosis (anti-TB) properties of the grafted samples were significantly (P < 0.001) increased compared to the unconjugated LMW-CH and LTG. Overall, functionalization of LTG with LMW-CH improved the anti-tuberculosis activity. Further studies are needed to explore the possibilities of its use in vivo models.

Overexpressed ZC3H13 suppresses papillary thyroid carcinoma growth through m6A modification-mediated IQGAP1 degradation

PURPOSE

The purpose of this study was to clarify the effect of ZC3H13 on the growth of papillary thyroid carcinoma (PTC).

METHODS

Firstly, we used qRT-PCR and Western blot to compare the difference in the expression of ZC3H13 between normal thyroid epithelial cells and PTC cell lines. Then, ZC3H13 overexpression/knockout thyroid cancer cells were constructed by lentivirus transfection, and the effects of overexpression of ZC3H13 on the proliferation, migration and invasion of PTC cells were detected by CCK8 and transwell experiments. Lastly, MeRIP-qPCR, RIP and o Actinomycin D were used to verify that ZC3H13 regulated the expression of downstream target gene IQGAP1 through m6A modification.

RESULTS

ZC3H13 expression was decreased in PTC cell lines BCPAP, KTC-1, k1, HTH83, and TPC-1. Proliferation, invasion, and migration of PTC cells were inhibited by overexpressed ZC3H13 but increased by knockdown of ZC3H13. IQGAP1 expression was suppressed by ZC3H13 overexpression but enhanced by ZC3H13 knockdown. In ZC3H13-overexpressed PTC cells, the m6A level of IQGAP1 mRNA was increased, and the IQGAP1 mRNA expression was decreased with the increasing time of Actinomycin D treatment. YTHDF2 enriched more IQGAP1 mRNA than IgG and knockdown of YTHDF2 reversed the effect of ZC3H13 overexpression on IQGAP1 mRNA stability. The xenograft tumor experiment in nude mice confirmed that the overexpression of ZC3H13 inhibited tumor growth, while overexpression of IQGAP1 could reverse the inhibitory effect of ZC3H13 overexpression on tumor growth.

CONCLUSION

ZC3H13 mediates IQGAP1 mRNA degradation by promoting m6A modification of IQGAP1 mRNA, this provides a prospective therapeutic target for PTC.

IQGAP1 and RNA Splicing in the Context of Head and Neck via Phosphoproteomics

IQGAP1 (IQ motif-containing GTPase-activating protein 1) scaffolds several signaling pathways in mammalian cells that are implicated in carcinogenesis, including the RAS and PI3K pathways that involve multiple protein kinases. IQGAP1 has been shown to promote head and neck squamous cell carcinoma (HNSCC); however, the underlying mechanism(s) remains unclear. Here, we report a mass spectrometry-based analysis identifying differences in phosphorylation of cellular proteins in vivo and in vitro in the presence or absence of IQGAP1. By comparing the esophageal phosphoproteome profiles between Iqgap1+/+ and Iqgap1-/- mice, we identified RNA splicing as one of the most altered cellular processes. Serine/arginine-rich splicing factor 6 (SRSF6) was the protein with the most downregulated levels of phosphorylation in Iqgap1-/- tissue. We confirmed that the absence of IQGAP1 reduced SRSF6 phosphorylation both in vivo and in vitro. We then expanded our analysis to human normal oral keratinocytes. Again, we found factors involved in RNA splicing to be highly altered in the phosphoproteome profile upon genetic disruption of IQGAP1. Both the Clinical Proteomic Tumor Analysis Consortium (CPTAC) and the Cancer Genome Atlas (TCGA) data sets indicate that phosphorylation of splicing-related proteins is important in HNSCC prognosis. The Biological General Repository for Interaction Datasets (BioGRID) repository also suggested multiple interactions between IQGAP1 and splicing-related proteins. Based on these collective observations, we propose that IQGAP1 regulates the phosphorylation of splicing proteins, which potentially affects their splicing activities and, therefore, contributes to HNSCC. Raw data are available from the MassIVE database with identifier MSV000087770.

Hormonal Crosstalk Between Thyroid and Breast Cancer

Differentiated thyroid cancer and breast cancer account for a significant portion of endocrine-related malignancies and predominately affect women. As hormonally responsive tissues, the breast and thyroid share endocrine signaling. Breast cells are responsive to thyroid hormone signaling and are affected by altered thyroid hormone levels. Thyroid cells are responsive to sex hormones, particularly estrogen, and undergo protumorigenic processes upon estrogen stimulation. Thyroid and sex hormones also display significant transcriptional crosstalk that influences oncogenesis and treatment sensitivity. Obesity-related adipocyte alterations-adipocyte estrogen production, inflammation, feeding hormone dysregulation, and metabolic syndromes-promote hormonal alterations in breast and thyroid tissues. Environmental toxicants disrupt endocrine systems, including breast and thyroid homeostasis, and influence pathologic processes in both organs through hormone mimetic action. In this brief review, we discuss the hormonal connections between the breast and thyroid and perspectives on hormonal therapies for breast and thyroid cancer. Future research efforts should acknowledge and further explore the hormonal crosstalk of these tissues in an effort to further understand the prevalence of thyroid and breast cancer in women and to identify potential therapeutic options.

Signal Pathway of Estrogen and Estrogen Receptor in the Development of Thyroid Cancer

The molecular mechanisms underlying the development of thyroid cancer (TC) have been examined through extensive experiments. A large number of studies have shown that the incidences of thyroid cancer in women is much higher than that in men, so estrogen plays a key role in the development of thyroid cancer. Estrogen plays its growth-promoting role through classical genomic and non-genomic pathways mediated by membrane-bound estrogen receptors. It also can affect tumor progression by regulating the tumor microenvironment. We summarize the understanding of molecular mechanisms of estrogen signaling pathways in thyroid cancer. Furthermore, it will provide a new target for the treatment of thyroid carcinoma by blocking estrogen and its related action pathway.

Association Between the Presence of Female-Specific Tumors and Aggressive Clinicopathological Features in Papillary Thyroid Cancer: A Retrospective Analysis of 9,822 Cases

Objective

To investigate the association between the presence of female-specific tumors and aggressive clinicopathological features in papillary thyroid cancer (PTC).

Methods

This study retrospectively analyzed 9,822 female cases between June 2008 and December 2017. Odds ratios and corresponding 95% confidence intervals were calculated. Findings were stratified by age and body mass index (BMI) in different models.

Results

1443/9822 (14.7%) patients with PTC had a female-specific tumor. Presence of a benign breast mass was an independent risk factor for a primary PTC lesion > 1 cm in diameter (adjusted OR = 1.446, 95% CI 1.136–1.840, P = 0.003), but a protective factor against extrathyroidal extension of PTC (adjusted OR = 0.650, 95%CI 0.500–0.845, P = 0.001). Presence of a benign uterine mass was an independent risk factor for multifocal PTC (adjusted OR = 1.305, 95%CI 1.113–1.531, P = 0.001). Analyses stratified by age and BMI revealed the presence of a benign breast mass was an independent risk factor for a primary PTC lesion > 1 cm in diameter in patients aged <36 years (adjusted OR = 1.711, 95% CI 1.063–2.754, P = 0.027), and a protective factor against extrathyroidal extension of PTC in patients aged ≥36 - <42 years (OR adjusted = 0.533, 95% CI 0.302–0.941, P = 0.030) or with a BMI ≥ 23.4 kg/m² (BMI ≥ 23.4 to < 25.7 kg/m², adjusted OR = 0.441, 95% CI 0.246–0.792, P = 0.006; BMI ≥25.7 kg/m², adjusted OR = 0.558, 95% CI 0.315–0.998, P₂ = 0.045). Presence of a benign uterine mass was an independent risk factor for multifocal PTC in patients aged ≥49 years (adjusted OR = 1.397, 95% CI 1.088–1.793, P = 0.009) or with a BMI <21.5 kg/m² (OR adjusted = 1.745, 95% CI 1.214–2.509, P = 0.003).

Conclusion

The presence of a benign breast mass was an independent risk factor for a primary PTC lesion > 1 cm in diameter and a protective factor against extrathyroidal extension of PTC, while the presence of a benign uterine mass was an independent risk factor for multifocal PTC. Data from this study may help surgeons propose more personalized treatment plans when encountering patients with PTC and female-specific benign tumors.

Comparing intestinal versus diffuse gastric cancer using a PEFF-oriented proteomic pipeline

Gastric cancer is the fifth most common malignant neoplasia and the third leading cause of cancer death worldwide. Mac-Cormick et al. recently showed the importance of considering the anatomical region of the tumor in proteomic gastric cancer studies; more differences were found between distinct anatomical regions than when comparing healthy versus diseased tissue. Thus, failing to consider the anatomical region could lead to differential proteins that are not disease specific. With this as motivation, we compared the proteomic profiles of intestinal and diffuse adenocarcinoma from the same anatomical region, the corpus. To achieve this, we used isobaric labeling (iTRAQ) of peptides, a 10-step HILIC fractionation, and reversed-phase nano-chromatography coupled online with a Q-Exactive Plus mass spectrometer. We updated PatternLab to take advantage of the new Comet-PEFF search engine that enables identifying post-translational modifications and mutations included in neXtProt's PSI Extended FASTA Format (PEFF) metadata. Our pipeline then uses a text-mining tool that automatically extracts PubMed IDs from the proteomic result metadata and drills down keywords from manuscripts related with the biological processes at hand. Our results disclose important proteins such as apolipoprotein B-100, S100 and 14-3-3 proteins, among many others, highlighting the different pathways enriched by each cancer type.

SIGNIFICANCE

Gastric cancer is a heterogeneous and multifactorial disease responsible for a significant number of deaths every year. Despite the constant improvement of surgical techniques and multimodal treatments, survival rates are low, mostly due to limited diagnostic techniques and late symptoms. Intestinal and diffuse types of gastric cancer have distinct clinical and pathological characteristics; yet little is known about the molecular mechanisms regulating these two types of gastric tumors. Here we compared the proteomic profile of diffuse and intestinal types of gastric cancer from the same anatomical location, the corpus, from four male patients. This methodological design aimed to eliminate proteomic variations resulting from comparison of tumors from distinct anatomical regions. Our PEFF-tailored proteomic pipeline significantly increased the identifications as when compared to previous versions of PatternLab.

Knockdown of IQGAP1 inhibits proliferation and epithelial-mesenchymal transition by Wnt/β-catenin pathway in thyroid cancer

Background

Thyroid cancer is the most common endocrine malignant disease with a high incidence rate. The expression of IQGAP1 is upregulated in various cancers, including thyroid cancer. However, the role and underlying mechanism of IQGAP1 in thyroid cancer are still not clear.

Materials and methods

The expression of IQGAP1 in thyroid cancer tissues and cells was determined by reverse transcription polymerase chain reaction and Western blot analysis. Cells were transfected with different siRNAs using Lipofectamine 2000 or were treated with various concentrations of XAV939. The effects of IQGAP1 knockdown on proliferation and epithelial–mesenchymal transition (EMT) of thyroid cancer cells were determined by MTT assay and Western blot analysis. Animal experiments were performed to investigate the effects of IQGAP1 knockdown on the growth of tumors in vivo.

Results

High IQGAP1 expression is found in thyroid cancer tissues and cells. Knockdown of IQGAP1 had inhibitory effects on cell proliferation and EMT, as well as on the Wnt/β-catenin pathway. Additionally, inactivation of the Wnt/β-catenin pathway by XAV939 or si-β-catenin suppressed cell proliferation and EMT. Furthermore, suppression of the Wnt/β-catenin pathway reversed the positive effects of pcDNA-IQGAP1 on cell proliferation and EMT in vitro. Moreover, downregulation of IQGAP1 suppressed tumor growth and EMT in SW579 tumor xenografts through the Wnt/β-catenin pathway in vivo.

Conclusion

Our study demonstrated that knockdown of IQGAP1 inhibited cell proliferation and EMT through blocking the Wnt/β-catenin pathway in thyroid cancer.