Klotho expression in cervical cancer: differential expression in adenocarcinoma and squamous cell carcinoma

Study on the preoperative value of serum SCC-Ag in predicting the stromal invasion of cervical squamous cell carcinoma

OBJECTIVE

To investigate the preoperative value of serum SCC-Ag in predicting the stromal invasion of cervical squamous cell carcinoma.

METHODS

This study retrospectively analyzed 78 patients with early cervical squamous cell carcinoma who underwent surgery as initial treatment at the Senior Department of Obstetrics and Gynecology, the Seventh Medical Center of PLA General Hospital from January 2018 to September 2022 was implemented. The clinicopathological characteristics were statistically compared. The ROC curve was drawn to determine the optimal critical level of  preoperative serum SCC-Ag value for predicting cervical stromal invasion.

RESULTS

The depth of myometrial invasion was not related to the age of diagnosis and HPV infection (p > 0.05), while it was related to tumor size, staging, tissue differentiation, LVSI, lymph node metastasis (LNM) and preoperative serum SCC-Ag value (p < 0.05).The area under the curve (AUC) of serum SCC-Ag value was 0.894 (p = 0.000, 95% CI 0.824-0.964), and preoperative serum SCC-Ag value 1.65 ng/ml was the best cutoff for predicting cervical stromal invasion in cervical squamous cell carcinoma. The sensitivity and specificity of diagnosis were 92.3% and 78.8%, respectively.

CONCLUSION

If the preoperative serum SCC-Ag leval more than 1.65 ng/ml in patients with cervical squamous cell carcinoma, the risk of cervical stromal invasion will increase, which can provide a reference for clinical treatment.

Inhibition of Wnt-β-Catenin Signaling by ICRT14 Drug Depends of Post-Transcriptional Regulation by HOTAIR in Human Cervical Cancer HeLa Cells

BACKGROUND

In Cervical cancer (CC), in addition to HPV infection, the most relevant alteration during CC initiation and progression is the aberrant activation of Wnt/β-catenin pathway. Several inhibitory drugs of this pathway are undergoing preclinical and clinical studies. Long non-coding RNAs (lncRNAs) are associated with resistance to treatments. In this regard, understanding the efficiency of drugs that block the Wnt/β-catenin pathway in CC is of relevance to eventually propose successful target therapies in patients with this disease.

METHODS

We analyzed the levels of expression of 249 components of the Wnt/β-catenin pathway in a group of 109 CC patients. Three drugs that blocking specific elements of Wnt/β-catenin pathway (C59, NSC668036 and ICRT14) by TOP FLASH assays and qRT-PCR were tested in vitro in CC cells.

RESULTS

137 genes of the Wnt/β-catenin pathway were up-regulated and 112 down-regulated in CC patient's samples, demonstrating that this pathway is dysregulated. C59 was an efficient drug to inhibit Wnt/β-catenin pathway in CC cells. NSC668036, was not able to inhibit the transcriptional activity of the Wnt/β-catenin pathway. Strikingly, ICRT14 was neither able to inhibit this pathway in HeLa cells, due to HOTAIR interaction with β-catenin, maintaining the Wnt/β-catenin pathway activated.

CONCLUSIONS

These results demonstrate a mechanism by which HOTAIR evades the effect of ICRT14, a Wnt/β-catenin pathway inhibitory drug, in HeLa cell line. The emergence of these mechanisms reveals new scenarios in the design of target therapies used in cancer.

Role of Fibroblast Growth Factor 23 (FGF23) and αKlotho in Cancer

Together with fibroblast growth factors (FGFs) 19 and 21, FGF23 is an endocrine member of the family of FGFs. Mainly secreted by bone cells, FGF23 acts as a hormone on the kidney, stimulating phosphate excretion and suppressing formation of 1,25(OH)₂D₃, active vitamin D. These effects are dependent on transmembrane protein αKlotho, which enhances the binding affinity of FGF23 for FGF receptors (FGFR). Locally produced FGF23 in other tissues including liver or heart exerts further paracrine effects without involvement of αKlotho. Soluble Klotho (sKL) is an endocrine factor that is cleaved off of transmembrane Klotho or generated by alternative splicing and regulates membrane channels, transporters, and intracellular signaling including insulin growth factor 1 (IGF-1) and Wnt pathways, signaling cascades highly relevant for tumor progression. In mice, lack of FGF23 or αKlotho results in derangement of phosphate metabolism and a syndrome of rapid aging with abnormalities affecting most organs and a very short life span. Conversely, overexpression of anti-aging factor αKlotho results in a profound elongation of life span. Accumulating evidence suggests a major role of αKlotho as a tumor suppressor, at least in part by inhibiting IGF-1 and Wnt/β-catenin signaling. Hence, in many malignancies, higher αKlotho expression or activity is associated with a more favorable outcome. Moreover, also FGF23 and phosphate have been revealed to be factors relevant in cancer. FGF23 is particularly significant for those forms of cancer primarily affecting bone (e.g., multiple myeloma) or characterized by bone metastasis. This review summarizes the current knowledge of the significance of FGF23 and αKlotho for tumor cell signaling, biology, and clinically relevant parameters in different forms of cancer.

Lysine-specific histone demethylase 1A (LSD1) in cervical cancer

Purpose

Demethylation of DNA through enzymes like LSD1 showed a crucial impact on different kind of cancers. Epigenetic modifications in cervical cancer are still not fully investigated nevertheless of high interest for a therapeutic use.

Methods

Tumor samples of 250 cervical cancer patients were immunochemically stained and evaluated based on Immunoreactive Score. Results were statistically analyzed for clinical and pathological parameters.

Results

Our patient collective showed a disadvantage for 10-year survival for patients with a strong expression of LSD1 in the cytoplasm of cervical cancer cells. The results of the correlational analysis further revealed a negative correlation of LSD1 to G-protein coupled estrogen receptor (GPER).

Conclusions

Epigenetic changes through enzymes like LSD1 may also be of interest for patients with cervical cancer. A combined therapy with other proteins relayed to cervical cancer like GPER might be of interest for future investigations.

Overexpression of klotho suppresses growth and pulmonary metastasis of osteosarcoma in vivo

Klotho is originally discovered as an anti-aging gene and knock-out of klotho accelerates aging in mice. Subsequent studies support the anti-carcinogenesis role of klotho in a variety of human malignancies. The present study investigated the role of klotho on growth and metastasis of osteosarcoma cells. The osteosarcoma cells were transduced with lentivirus particles encoding klotho or scramble control. The reconstructed osteosarcoma cells were injected into the femoral medullary cavity of nude mice to establish a xenograft animal model. The anti-tumor properties of klotho were evaluated in terms of tumor growth, apoptosis, glycogen production, and pulmonary metastasis. Lentivirus-mediated overexpression of klotho significantly decreased tumor volume and weight in osteosarcoma mice. Determination of PCNA and Ki67 expression revealed that overexpression of klotho inhibited cell proliferation in tumor tissues obtained from osteosarcoma xenografts. PAS staining also showed that overexpression of klotho significantly decreased the production of glycogen in osteosarcoma. Moreover, TUNEL positive cells were significantly increased after lentivirus-mediated overexpression of klotho. Furthermore, lentivirus-mediated upregulation of klotho reduced the number of pulmonary metastatic lesions in mice compared to control mice. These findings demonstrated that elevated klotho could inhibit osteosarcoma cell growth and pulmonary metastasis in vivo, suggesting that klotho may be a valuable therapeutic target for osteosarcoma.

Cross-contamination of the human salivary gland HSG cell line with HeLa cells: A STR analysis study

OBJECTIVES

The human salivary gland (HSG) cell line, labeled as a submandibular ductal cell line, is commonly used as in vitro models to study radiation therapy, Sjögren's syndrome, pleomorphic adenoma, mucocele, epithelial-to-mesenchymal transition, and epigenetics. However, the American Type Culture Collection (ATCC) has recently released a list of cross-contaminated cell lines that included HSG. Despite this notice, some research laboratories still use HSG as a salivary cell model. Therefore, this study examined the authenticity of HSG sampled from three different laboratories.

METHODS

DNA was extracted from HSG and additional salivary cell lines (NS-SV-AC, NS-SV-DC, A253, HSY) and submitted for cell line authentication with short tandem repeat (STR) analysis.

RESULTS

All HSG samples had STR profiles indicating >80% match with HeLa in both the ATCC and Deutsche Sammlung von Mikroorganismen und Zellkulturen (DSMZ) databases. This confirmed that HSG sampled from three different laboratories and HSY shared a common ancestry (host) with HeLa, whereas NS-SV-AC, NS-SV-DC, and A253 had unique STR profiles.

CONCLUSION

Short tandem repeat analysis revealed that HSG was contaminated by the HeLa cell line. Furthermore, because genotyping of the original HSG cell line was not performed during its establishment, it will be difficult to authenticate an uncontaminated sample of HSG.

Association between klotho expression and malignancies risk and progression: A meta-analysis

BACKGROUND

We assessed the association between tissue klotho protein expression and the risk and progression of malignancies.

METHODS

We searched the electronic databases for the studies regarding the relationship between tissue klotho protein expression and risk/progression of malignancies through January 2018. We calculated the pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to evaluate the impact of tissue klotho protein expression on malignancies. A fixed-effect model, or in the presence of heterogeneity, random- effect model was applied to calculate the combined ORs.

RESULTS

Eighteen studies were recruited in our pooled-analysis. Overall malignancies including liver cancer, pancreatic ductal adenocarcinoma (PDAC), ovarian cancer, esophageal squamous cell carcinoma (ESCC), neuroendocrine cancer, oral cancer and bladder cancer demonstrated significantly lower ORs than those in controls (p < 0.05). Malignancies with tissue klotho protein expression showed a pooled hazard ratio (95% CI 0.784-2.479). Malignancies with tissue klotho protein expression showed a similar OR (95% CI 0.732-1.335) of male/total to cases without tissue klotho protein expression. Malignancies with tissue klotho protein expression showed a markedly lower OR (95% CI 0.454-0.941) of metastasis compared with those without tissue klotho protein expression. Malignancies with tissue klotho protein expression showed a markedly higher OR (95% CI 1.041-1.800) of stage I-II/III-IVcompared with those without tissue klotho protein expression. Malignancies with tissue klotho protein expression showed a similar OR (95% CI 0.948-3.407) of differentiation to cases without tissue klotho protein expression. Sensitivity analysis did not change the overall results significantly. No marked publication bias was noted.

CONCLUSIONS

Tissue klotho protein expression was associated with a lower risk and progression of malignancies. Klotho may be a protective factor against malignancies risk/progression.

Effects of Klotho on fibrosis and cancer: A renal focus on mechanisms and therapeutic strategies

Klotho is a membrane-bound protein predominantly expressed in the kidney, where it acts as a permissive co-receptor for Fibroblast Growth Factor 23. In its shed form, Klotho exerts anti-fibrotic effects in several tissues. Klotho-deficient mice spontaneously develop fibrosis and Klotho deficiency exacerbates the disease progression in fibrotic animal models. Furthermore, Klotho overexpression or supplementation protects against fibrosis in various models of renal and cardiac fibrotic disease. These effects are mediated at least partially by the direct inhibitory effects of soluble Klotho on TGFβ1 signaling, Wnt signaling, and FGF2 signaling. Soluble Klotho, as present in the circulation, appears to be the primary mediator of anti-fibrotic effects. Similarly, through inhibition of the TGFβ1, Wnt, FGF2, and IGF1 signaling pathways, Klotho also inhibits tumorigenesis. The Klotho promoter gene is generally hypermethylated in cancer, and overexpression or supplementation of Klotho has been found to inhibit tumor growth in various animal models. This review focuses on the protective effects of soluble Klotho in inhibiting renal fibrosis and fibrosis in distant organs secondary to renal Klotho deficiency. We also discuss the structure-function relationships of Klotho domains and biological effects in the context of potential targeted treatment strategies.

Klotho expression is correlated to molecules associated with epithelial-mesenchymal transition in lung squamous cell carcinoma

Klotho is known as an anti-aging gene. We previously reported that the expression of Klotho is a postoperative prognostic factor for patients with lung large cell neuroendocrine carcinoma and lung small cell carcinoma. Recently, Klotho was shown to suppress the epithelial-mesenchymal transition (EMT). In the present study, we examined the association between the expression of Klotho and the regulation of EMT in lung squamous cell carcinoma. We immunohistochemically examined the expression of Klotho in patients with lung squamous cell carcinoma who had undergone surgical resection or photodynamic therapy. The immunohistochemical analysis showed that Klotho expression was observed not only in normal bronchial epithelial cells, but also in centrally located early lung cancers, which were all carcinomas in situ and were treated using PDT. However, in lung cancer patients with invasive and or advanced squamous cell carcinoma who had undergone a complete surgical resection, Klotho expression was observed in only 4 patients (13%). To elucidate the associations between the expression of Klotho and the expressions of EMT-related proteins, such as E-cadherin, N-cadherin, vimentin, and Snail, we transiently transfected GFP-Klotho plasmid DNA into the human squamous lung cancer cell line SQ5 and examined the expressions of these proteins of GFP-positive cells after sorting using flow cytometry. In SQ5 cells overexpressing GFP-Klotho, the expression of N-cadherin, which is a mesenchymal marker, was completely inhibited, compared with that in SQ5 cells transfected with the GFP vector. The overexpression of Klotho did not affect the regulation of either other mesenchymal markers (such as vimentin and Snail) or the regulation of an epithelial marker (E-cadherin). We concluded that the expression of Klotho was related to the degree of cancer invasiveness and that Klotho inhibits the expression of N-cadherin and regulates the EMT in lung cancer.

Tissue expression and source of circulating αKlotho

αKlotho (Klotho), a type I transmembrane protein and a coreceptor for Fibroblast Growth Factor-23, was initially thought to be expressed only in a limited number of tissues, most importantly the kidney, parathyroid gland and choroid plexus. Emerging data may suggest a more ubiquitous Klotho expression pattern which has prompted reevaluation of the restricted Klotho paradigm. Herein we systematically review the evidence for Klotho expression in various tissues and cell types in humans and other mammals, and discuss potential reasons behind existing conflicting data. Based on current literature and tissue expression atlases, we propose a classification of tissues into high, intermediate and low/absent Klotho expression. The functional relevance of Klotho in organs with low expression levels remain uncertain and there is currently limited data on a role for membrane-bound Klotho outside the kidney. Finally, we review the evidence for the tissue source of soluble Klotho, and conclude that the kidney is likely to be the principal source of circulating Klotho in physiology.

Klotho suppresses tumor progression via inhibiting IGF-1R signaling in T‑cell lymphoma

Klotho is a transmembrane protein and acts as an upstream modulator of insulin-like growth factor-1 receptor (IGF-1R) signaling, which was indicated to be involved in the pathogenesis of solid cancer and hematological malignancies, including T‑cell lymphoma. Although Klotho was recently identified as a tumor suppressor in several types of human malignancies, the potential role of Klotho in T‑cell lymphoma has not been reported. In the present study, we investigated the expression level and the molecular events of Klotho in T‑cell lymphoma. Significantly lower expression of Klotho was observed in T‑cell lymphoma patient samples compared to normal lymph nodes. Functional analysis after Klotho overexpression revealed significantly inhibited tumor cell viability in T‑cell lymphoma. Moreover, apoptosis of T‑cell lymphoma cells were induced after transfected with Klotho-overexpressing vectors. Forced expression of Klotho resulted in decline of activation of IGF-1R signaling, accompanied by decreased phosphorylation of its downstream targets, including AKT and ERK1/2. These data indicated that Klotho acts as a tumor suppressor via inhibiting IGF-1R signaling, thus suppressing the viability and promoting apoptosis in T‑cell lymphoma. Taken together, Klotho may serve as a potential target for the therapeutic intervention of T‑cell lymphoma.

Fibroblast growth factor-mediated crosstalk in cancer etiology and treatment

It is becoming increasingly evident that multiple cell types within the tumor work together to drive tumour progression and impact on both the response to therapy and the dissemination of tumour cells throughout the body. Fibroblast growth factor signalling (FGF) is perturbed in a number of tumors, serving to drive tumor cell proliferation and migration, but also has a central role in orchestrating the plethora of cells that comprise the tumor microenvironment. This review focuses on how this family of signalling molecules can influence the interactions between tumor cells and their surrounding environment. Unraveling the complexities of FGF signalling between the distinct cell types of a tumor may identify additional opportunities for FGF-targeted compounds in therapy and could help combat drug resistance. Developmental Dynamics 246:493-501, 2017. © 2017 Wiley Periodicals, Inc.

Klotho, an anti-aging gene, acts as a tumor suppressor and inhibitor of IGF-1R signaling in diffuse large B cell lymphoma

Background

Klotho, is a transmembrane protein, performs as a circulating hormone and upstream modulator of the insulin-like growth factor-1 receptor (IGF-1R), fibroblast growth factor (FGF), and Wnt signaling pathways. These pathways are involved in the development and progression of B cell lymphoma. We aimed to explore the expression pattern and functional mechanism of Klotho in diffuse large B cell lymphoma (DLBCL).

Methods

Immunohistochemistry (IHC) and western blotting were performed to detect the expression level of Klotho in DLBCL patients and cell lines. Tumor suppressive effect of Klotho was determined by both in vitro and in vivo studies. Signaling pathway activity was assessed by western blotting.

Results

Remarkable lower expression levels of Klotho were observed in DLBCL patients and cell lines. Enforced expression of Klotho could significantly induce cell apoptosis and inhibit tumor growth in DLBCL. Upregulation of Klotho resulted in declined activation of IGF-1R signaling, accompanied with decreased phosphorylation of its downstream targets, including AKT and ERK1/2. Moreover, xenograft model treated with either Klotho overexpression vector or recombinant human Klotho administration presented restrained tumor growth and lower Ki67 staining.

Conclusions

Our findings establish that Klotho performs as a tumor suppressor and modulator of IGF-1R signaling in DLBCL. Targeting Klotho may provide novel strategies for future therapeutic intervention.

The Role of Alpha-Klotho as a Universal Tumor Suppressor

The klotho gene is implicated in many physiological activities, among them aging, glucose metabolism, and phosphate and calcium metabolism. Many cellular activities of klotho were implicated in promoting these activities. Two of them, inhibition of the insulin-like growth factor-1 pathway and of the Wnt signaling pathway, are also major pathways associated with cancer development and progression. These discoveries prompted a surge of research aiming to elucidate the role of klotho in cancer. Studies show that klotho is universally silenced in a wide array of malignancies, including breast, pancreatic, ovarian, lung, colorectal, and melanoma, and that klotho's expression can serve as an invaluable prognostic marker. Epigenetic mechanisms, ie, promoter hypermethylation and histone deacetylation, are mainly associated with klotho's silencing; however, different micro-RNAs were also demonstrated to be involved in the process. The activity of klotho on cancer cells growth was also widely investigated, and accumulating data suggest that klotho forced expression or treatment with the soluble protein can inhibit cancer development and progression. Moreover, studies now aim to reveal the specific region in klotho protein that underlies this anticancer activity in order to develop efficient and safe klotho-based medications.