FAM172A protein promotes the proliferation of human papillary thyroid carcinoma cells via the p38 mitogen-activated protein kinase pathway

Loss of FAM172A gene prompts cell proliferation in liver regeneration

The present study was designed to explore the function of FAM172A in liver regeneration and HCC. Mice were sacrificed after 70% partial hepatectomy (PH). RNA sequencing was performed on primary hepatocytes of WT and FAM172A-/- mice. We used HepG2 cells to construct cell lines with stably knockdown and overexpression of FAM172A. The expression of FAM172A in liver tissues was investigated by immunohistochemical staining, and we also used public database to perform survival analysis and prognostic model in HCC. Compared with WT mice after PH, normalized liver weight/body weight (LW/BW) ratio and the proliferating cell nuclear antigen (PCNA) protein level of FAM172A-/- mice elevated. The DEGs were mainly enriched in inflammatory response, tumor necrosis factor production, and wound healing. FAM172A knockdown enhanced the NFκB-TNFα and pERK-YAP1-Cyclin D1 axis. FAM172A peptide inhibited proliferation of primary hepatocytes. Moreover, the low expression of FAM172A in human HCC tissues implies a lower likelihood of survival and a valid diagnostic marker for HCC. Loss of FAM172A gene promotes cell proliferation by pERK-YAP1-Cyclin D1 and pNFκB-TNFα pathways during liver regeneration after PH. FAM172A may be a favorable diagnosis marker of HCC.

FAM172A Deletion May Enhance Hepatic Steatosis by Promoting ER Stress

BACKGROUND

Endoplasmic reticulum (ER) stress is one of the major causes to the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Our previous study showed that maintains the homeostasis of ER could effectively alleviate NAFLD. In this study, we found that the loss of FAM172A increased ER stress.

AIMS

The aims of this study were to explore whether FAM172A could improve NAFLD by inhibiting ER stress.

METHODS

The expression levels of FAM172A and ER stress were detected by western blot. The method of immunofluorescence was used to determine FAM172A location. The interacted proteins of FAM172A were identified by immunocoprecipitation. The methods of MTS and caspase-3/7 activity were taken to confirm the effect of FAM172A on cell viability and proliferation. The expression levels of inflammation were detected by qPCR.

RESULTS

We confirmed that FAM172A might alleviate NAFLD through inhibiting ER stress. Loss of FAM172A increased the expressions of ATF6, peIF2α, but decreased the expression of IRE1α. Then, it was shown that FAM172A located in ER and FAM172A directly interacted with ATF6 and peIF2α and IRE1α. More importantly, the binding of FAM172A and eIF2a in tunicamycin-treated group increased significantly compared with the control group. However, the binding of FAM172A and ATF6 or IRE1α did not change. Next, we found that the lack of FAM172A could produce more apoptosis and inflammation.

CONCLUSIONS

Our results suggest that FAM172A improve steatosis by alleviating ER stress.

Deletion of Fam172a accelerates advanced atherosclerosis and induces plaque instability

BACKGROUND AND AIMS

Vascular smooth muscle cells (VSMCs) play a critical role in atherosclerosis. The family with sequence similarity 172, member A (FAM172A) is a novel protein and its role in atherosclerosis has not been explored so far. Therefore, our aim is to investigate whether FAM172A affects atheroprogression through VSMCs and its possible mechanism.

METHODS

Fam172a^-/- mice were generated using CRISPR/Cas9 technology. Fam172a^-/- and Apoe^-/- double knockout (Fam172a^-/-/Apoe^-/-) mice and their littermates (Fam172a^+/+/Apoe^-/-) were fed with a Western diet for 18 weeks to induce advanced atherosclerotic lesions. The role and mechanism of Fam172a in phenotypic switching, proliferation and migration of VSMCs were investigated through in vivo and in vitro experiments.

RESULTS

Compared with Fam172a^+/+/Apoe^-/- mice, Fam172a^-/-/Apoe^-/- mice showed increased atherosclerotic lesion size and plaque instability such as increased necrotic core area and decreased fiber deposition. Additionally, knockout of Fam172a promoted expression of CD68 and KLF4 and decreased expression of α-SMA and SM22α in atherosclerotic lesions. Furthermore, overexpression of Fam172a promoted Movas cells proliferation and migration, increased expression of α-SMA and SM22α and decreased expression of KLF4. Meanwhile, knockdown of Fam172a in Movas cells and deletion of Fam172a in VSMCs from Fam172a^-/-/Apoe^-/- mice showed opposite phenotypes. Similar phenotypes were also observed in human aortic smooth muscle cells.

CONCLUSIONS

Our results provide the first direct evidence that Fam172a has a protective role in advanced atherosclerosis by increasing atherosclerotic plaque stability and inhibiting transition of VSMCs from contractile to synthetic phenotype, which may be through KLF4-dependent pathway.

FAM172A promotes follicular thyroid carcinogenesis and may be a marker of FTC

Our aims were to uncover the role of FAM172A (Family with sequence similarity 172 member A) in the pathogenesis of follicular thyroid carcinoma (FTC) and to evaluate its value in the differential diagnosis between malignant and benign thyroid follicular lesions. FAM172A expression was evaluated by q-PCR, immunoblotting and immunohistochemistry (IHC). The ability of proliferation, migration and invasion of cells were assessed by Cell Counting Kit-8 assay (CCK8), clone-formation and Transwell assays. Nude mouse tumorigenicity assays were used to investigate the role of FAM172A in the pathogenesis of FTC in vivo. The value of FAM172A in the differential diagnosis for FTC was assessed using 120 formalin-fixed paraffin-embedded (FFPE) tissues after the operation and 81 fine-needle aspiration biopsy (FNAB) samples before the operation. FAM172A was highly expressed in FTC tissues and FTC cell lines. Downregulation of FAM172A inhibited the proliferation, invasion and migration of FTC cells through Erk1/2 and JNK pathways. Subcutaneous tumorigenesis in nude mice showed that knockdown of FAM172A inhibited tumor growth and progression in vivo. The FAM172A IHC scores of 3.5 had 92% sensitivity and 63% specificity to separate FTC from benign/borderline thyroid follicular lesions, and 92% sensitivity and 80% specificity to discriminate FTC from benign thyroid follicular lesions in postoperative FFPE samples. The corresponding values were 75 and 78%, and 75 and 89% in preoperative FNA samples, respectively. FAM172A plays an important role in the pathogenesis of FTC through Erk1/2 and JNK pathways. FAM172A may be a potential marker for the preoperative diagnosis of FTC based on the IHC results of thyroid FNAB samples.

FAM172A inhibits EMT in pancreatic cancer via ERK-MAPK signaling

FAM172A, as a newly discovered gene, is little known in cancer development, especially in pancreatic cancer (PC). We investigated the potential role and molecular mechanism of FAM172A in epithelial to mesenchymal transition (EMT) in both human clinical samples and PC cells. FAM172A was downregulated in human PC tissues compared with that in non-cancerous pancreas cells by immunohistochemistry and qRT-PCR. FAM172A expression was negatively associated with tumor size (P=0.015), T stage (P=0.006), lymph node metastasis (P=0.028) and the worst prognosis of PC patients (P=0.004). Meanwhile, a positive relationship between FAM172A and E-cadherin (E-cad) (r=0.381, P=0.002) was observed in clinical samples, which contributed to the better prognosis of PC patients (P=0.014). FAM172A silencing induced EMT in both AsPC-1 and BxPC-3 cells, including inducing the increase of Vimentin, MMP9 and pERK and the decrease of E-cad and β-catenin expression, stimulating EMT-like cell morphology and enhancing cell invasion and migration in PC cells. However, MEK1 inhibitor PD98059 reversed FAM172A silencing-enhanced EMT in PC cells. We conclude that FAM172A inhibits EMT of PC cells via ERK-MAPK signaling.

The Effect of Protein FAM172A on Proliferation in HepG2 Cells and Investigation of the Possible Molecular Mechanism

Background

In our previous study, we found that the FAM172A recombinant protein could promote proliferation of L02 cells. However, the underlying mechanisms are still unknown. The present study was aimed at investigating the effect of FAM172A on proliferation of HepG2 cells and exploring the possible molecular mechanisms and its role in hepatocellular carcinoma (HCC).

Methods

Cell proliferation was measured by MTT assay. Western blot test was carried out to investigate the mechanism. Rabbit antibodies against FAM172A and membrane proteins isolated from lysate of HepG2 cell were coprecipitated and the resultant precipitates were analyzed by mass spectrum.

Results

The MTT assay showed that recombinant protein FAM172A isoform 1 (FAM172A-1) could induce HepG2 cell proliferation at the concentration of 10-100 ng/mL, while protein FAM172A isoform 3 (FAM172A-3) was at the concentration of 80-100 ng/mL. Western blot demonstrated that both FAM172A-1 and FAM172A-3 could activate the mitogen-activated protein kinase/extracellular signal-regulated protein kinase (MAPK/ERK) pathway and the phosphatidylinositol 3-kinase/threonine-protein kinase (PI3K/Akt) pathway. Mass spectrum analysis suggested that there were some membrane proteins interacting with FAM172A. Several candidate interacting proteins might mediate proliferation signals induced by FAM172A recombinant protein, including seven membrane proteins.

Conclusion

In conclusion, FAM172A recombinant protein could induce proliferation of HepG2 cells, in which the MAPK/ERK and PI3K/Akt signaling pathways might be involved. The role of FAM172A in HepG2 cell proliferation also indicated its possible involvement in HCC. The receptor of FAM172A on cells still needs to be exploited.

Detection of FAM172A expressed in circulating tumor cells is a feasible method to predict high-risk subgroups of colorectal cancer

Previous studies used to enumerate circulating tumor cells to predict prognosis and therapeutic effect of colorectal cancer. However, increasing studies have shown that only circulating tumor cells enumeration was not enough to reflect the heterogeneous condition of tumor. In this study, we classified different metastatic-potential circulating tumor cells from colorectal cancer patients and measured FAM172A expression in circulating tumor cells to improve accuracy of clinical diagnosis and treatment of colorectal cancer. Blood samples were collected from 45 primary colorectal cancer patients. Circulating tumor cells were enriched by blood filtration using isolation by size of epithelial tumor cells, and in situ hybridization with RNA method was used to identify and discriminate subgroups of circulating tumor cells. Afterwards, FAM172A expression in individual circulating tumor cells was measured. Three circulating tumor cell subgroups (epithelial/biophenotypic/mesenchymal circulating tumor cells) were identified using epithelial-mesenchymal transition markers. In our research, mesenchymal circulating tumor cells significantly increased along with tumor progression, development of distant metastasis, and vascular invasion. Furthermore, FAM172A expression rate in mesenchymal circulating tumor cells was significantly higher than that in epithelial circulating tumor cells, which suggested that FAM172A may correlate with malignant degree of tumor. This hypothesis was further verified by FAM172A expression in mesenchymal circulating tumor cells, which was strictly related to tumor aggressiveness factors. Mesenchymal circulating tumor cells and FAM172A detection may predict highrisk stage II colorectal cancer. Our research proved that circulating tumor cells were feasible surrogate samples to detect gene expression and could serve as a predictive biomarker for tumor evaluation.

FAM172A expression in circulating tumor cells for prediction of high-risk subgroups of colorectal cancer

Objectives

Previous studies used enumerated circulating tumor cells (CTCs) to predict prognosis and therapeutic effect in several types of cancers. However, increasing evidence showed that only enumerated CTCs were not enough to reflect the heterogeneity of tumors. Therefore, we classified different metastasis potentials of CTCs from colorectal cancer (CRC) patients to improve the accuracy of prognosis by CTCs.

Methods

Blood samples were collected from 45 primary CRC patients. CTCs were enriched by blood filtration, and the RNA in situ hybridization method was used to identify and discriminate subgroups of CTCs. Later, FAM172A expression in individual CTCs was measured.

Results

Three CTC subgroups (epithelial/biophenotypic/mesenchymal CTCs) were identified using epithelial–mesenchymal transition markers. In our research, mesenchymal CTCs significantly increased along with tumor progression, including developing distant metastasis and vascular invasion. Furthermore, FAM172A expression rate in mesenchymal CTCs was significantly higher than that in epithelial CTCs, which suggested that FAM172A may correlate with tumor malignancy. This hypothesis was further verified by FAM172A expression in mesenchymal CTCs strictly related to tumor aggressiveness factors. Finally, we revealed that mesenchymal CTCs and FAM172A expression may predict high-risk subgroups in stage II CRC.

Conclusion

Our research proved that CTCs could serve as feasible surrogate samples to detect gene expression as a predictive biomarker for tumor evaluation.

Identification of Differentially Expressed Kinase and Screening Potential Anticancer Drugs in Papillary Thyroid Carcinoma

Aim. We aim to identify protein kinases involved in the pathophysiology of papillary thyroid carcinoma (PTC) in order to provide potential therapeutic targets for kinase inhibitors and unfold possible molecular mechanisms. Materials and Methods. The gene expression profile of GSE27155 was analyzed to identify differentially expressed genes and mapped onto human protein kinases database. Correlation of kinases with PTC was addressed by systematic literature search, GO and KEGG pathway analysis. Results. The functional enrichment analysis indicated that “mitogen-activated protein kinases pathway” expression was extremely enriched, followed by “neurotrophin signaling pathway,” “focal adhesion,” and “GnRH signaling pathway.” MAPK, SRC, PDGFRa, ErbB, and EGFR were significantly regulated to correct these pathways. Kinases investigated by the literature on carcinoma were considered to be potential novel molecular therapeutic target in PTC and application of corresponding kinase inhibitors could be possible therapeutic tool. Conclusion. SRC, MAPK, and EGFR were the most important differentially expressed kinases in PTC. Combined inhibitors may have high efficacy in PTC treatment by targeting these kinases.