Radiotherapy modulates expression of EGFR, ERCC1 and p53 in cervical cancer

Neoadjuvant Therapies Do Not Reduce Epidermal Growth Factor Receptor (EGFR) Expression or EGFR-Targeted Fluorescence in a Murine Model of Soft-Tissue Sarcomas

PURPOSE

ABY-029, an epidermal growth factor receptor (EGFR)-targeted, synthetic Affibody peptide labeled with a near-infrared fluorophore, is under investigation for fluorescence-guided surgery of sarcomas. To date, studies using ABY-029 have occurred in tumors naïve to chemotherapy (CTx) and radiation therapy (RTx), although these neoadjuvant therapies are frequently used for sarcoma treatment in humans. The goal of this study was to evaluate the impact of CTx and RTx on tumor EGFR expression and ABY-029 fluorescence of human soft-tissue sarcoma xenografts in a murine model.

PROCEDURES

Immunodeficient mice (n = 98) were divided into five sarcoma xenograft groups and three treatment groups - CTx only, RTx only, and CTx followed by RTx, plus controls. Four hours post-injection of ABY-029, animals were sacrificed followed by immediate fluorescence imaging of ex vivo adipose, muscle, nerve, and tumor tissues. Histological hematoxylin and eosin staining confirmed tumor type, and immunohistochemistry staining determined EGFR, cluster of differentiation 31 (CD31), and smooth muscle actin (SMA) expression levels. Correlation analysis (Pearson's correlation coefficients, r) and linear regression (unstandardized coefficient estimates, B) were used to determine statistical relationships in molecular expression and tissue fluorescence between xenografts and treatment groups.

RESULTS

Neoadjuvant therapies had no broad impact on EGFR expression (|B|≤ 7.0, p ≥ 0.4) or on mean tissue fluorescence (any tissue type, (|B|≤ 2329.0, p ≥ 0.1). Mean tumor fluorescence was significantly related to EGFR expression (r = 0.26, p = 0.01), as expected.

CONCLUSION

Results suggest that ABY-029 as an EGFR-targeted, fluorescent probe is not negatively impacted by neoadjuvant soft-tissue sarcoma therapies, although validation in humans is required.

Identification of 3-(5-cyano-6-oxo-pyridin-2-yl)benzenesulfonamides as novel anticancer agents endowed with EGFR inhibitory activity

New 5-cyano-6-oxo-pyridine-based sulfonamides (6a-m and 8a-d) were designed and synthesized to potentially inhibit both the epidermal growth factor receptor (EGFR) and carbonic anhydrase (CA), with anticancer properties. First, the in vitro anticancer activity of each target substance was tested using Henrietta Lacks cancer cell line and M.D. anderson metastasis breast cancer cell line cells. Then, the possible CA inhibition against the human CA isoforms I, II, and IX was investigated, together with the EGFR inhibitory activity, with the most powerful derivatives. The neighboring methoxy group may have had a steric effect on the target sulfonamides, which prevented them from effectively inhibiting the CA isoforms while effectively inhibiting the EGFR. The effects of the 5-cyanopyridine derivatives 6e and 6l on cell-cycle disruption and the apoptotic potential were then investigated. To investigate the binding mechanism and stability of the target molecules, thorough molecular modeling assessments, including docking and dynamic simulation, were performed.

Review of possible mechanisms of radiotherapy resistance in cervical cancer

Radiotherapy is one of the main treatments for cervical cancer. Early cervical cancer is usually considered postoperative radiotherapy alone. Radiotherapy combined with cisplatin is the standard treatment for locally advanced cervical cancer (LACC), but sometimes the disease will relapse within a short time after the end of treatment. Tumor recurrence is usually related to the inherent radiation resistance of the tumor, mainly involving cell proliferation, apoptosis, DNA repair, tumor microenvironment, tumor metabolism, and stem cells. In the past few decades, the mechanism of radiotherapy resistance of cervical cancer has been extensively studied, but due to its complex process, the specific mechanism of radiotherapy resistance of cervical cancer is still not fully understood. In this review, we discuss the current status of radiotherapy resistance in cervical cancer and the possible mechanisms of radiotherapy resistance, and provide favorable therapeutic targets for improving radiotherapy sensitivity. In conclusion, this article describes the importance of understanding the pathway and target of radioresistance for cervical cancer to promote the development of effective radiotherapy sensitizers.

Perspectives of ERCC1 in early-stage and advanced cervical cancer: From experiments to clinical applications

Cervical cancer is a public health problem of extensive clinical importance. Excision repair cross-complementation group 1 (ERCC1) was found to be a promising biomarker of cervical cancer over the years. At present, there is no relevant review article that summarizes such evidence. In this review, nineteen eligible studies were included for evaluation and data extraction. Based on the data from clinical and experimental studies, ERCC1 plays a key role in the progression of carcinoma of the uterine cervix and the therapeutic response of chemoradiotherapy. The majority of the included studies (13/19, 68%) suggested that ERCC1 played a pro-oncogenic role in both early-stage and advanced cervical cancer. High expression of ERCC1 was found to be associated with the poor survival rates of the patients. ERCC1 polymorphism analyses demonstrated that ERCC1 might be a useful tool for predicting the risk of cervical cancer and the treatment-related toxicities. Experimental studies indicated that the biological effects exerted by ERCC1 in cervical cancer might be mediated by its associated genes and affected signaling pathways (i.e., XPF, TUBB3, and. To move towards clinical applications by targeting ERCC1 in cervical cancer, more clinical, in-vitro, and in-vivo investigations are still warranted in the future.

p53 Modulates Radiosensitivity in Head and Neck Cancers-From Classic to Future Horizons

p53, initially considered a tumor suppressor, has been the subject of research related to cancer treatment resistance in the last 30 years. The unfavorable response to multimodal therapy and the higher recurrence rate, despite an aggressive approach, make HNSCC a research topic of interest for improving therapeutic outcomes, even if it is only the sixth most common malignancy worldwide. New advances in molecular biology and genetics include the involvement of miRNA in the control of the p53 pathway, the understanding of mechanisms such as gain/loss of function, and the development of different methods to restore p53 function, especially for HPV-negative cases. The different ratio between mutant p53 status in the primary tumor and distant metastasis originating HNSCC may serve to select the best therapeutic target for activating an abscopal effect by radiotherapy as a "booster" of the immune system. P53 may also be a key player in choosing radiotherapy fractionation regimens. Targeting any pathway involving p53, including tumor metabolism, in particular the Warburg effect, could modulate the radiosensitivity and chemo-sensitivity of head and neck cancers.

Prognostic Significance of HER3 Expression in Patients with Cervical Cancer

HER3 has been recognized to have an oncogenic role in various types of cancer. However, its prognostic significance has not been elucidated in cervical cancer. The aim of this study was to investigate the prognostic significance of HER3 expression in cervical cancer using immunohistochemistry (IHC). HER3 immunohistochemical staining was performed on the tumor tissue samples of 336 cervical cancer patients. The association between the clinicopathological characteristics and patient survival analysis was assessed according to HER3 expression. HER3 IHC staining was positive in 31.0% (104/336) of the cervical cancer patients. A higher proportion of adeno-/adenosquamous carcinoma was observed in the HER3-positive group (34.6%) than in the HER3-negative group (18.8%). In survival analysis, HER3 expression was significantly associated with poorer disease-free survival (DFS) and overall survival (OS) (p < 0.001 and p = 0.002, respectively). Multivariate analysis also indicated that HER3 expression was an independent prognostic factor for DFS (hazard ratio (HR) = 2.58, 95% confidence interval (CI) 1.42−4.67, p = 0.002) and OS (HR = 3.21, 95% CI, 1.26−8.14, p = 0.014). HER3 protein expression was a poor prognostic factor of survival in patients with cervical cancer. This finding could help to provide individualized management for these patients.

A Comprehensive Understanding of the Anticancer Mechanisms of FDY2004 Against Cervical Cancer Based on Network Pharmacology

Herbal drugs are continuously being developed and used as effective therapeutics for various cancers, such as cervical cancer (CC); however, their mechanisms of action at a systemic level have not been explored fully. To study such mechanisms, we conducted a network pharmacological investigation of the anti-CC mechanisms of FDY2004, an herbal drug consisting of Moutan Radicis Cortex, Persicae Semen , and Rhei Radix et Rhizoma. We found that FDY2004 inhibited the viability of human CC cells. By performing pharmacokinetic evaluation and network analysis of the phytochemical components of FDY2004, we identified 29 bioactive components and their 116 CC-associated pharmacological targets. Gene ontology enrichment analysis showed that the modulation of cellular functions, such as apoptosis, growth, proliferation, and survival, might be mediated through the FDY2004 targets. The therapeutic targets were also key components of CC-associated oncogenic and tumor-suppressive pathways, including PI3K-Akt, human papillomavirus infection, IL-17, MAPK, TNF, focal adhesion, and viral carcinogenesis pathways. In conclusion, our data present a comprehensive insight for the mechanisms of the anti-CC properties of FDY2004.

A systematic review and meta-analysis of the prevalence of therapeutic targets in cervical cancer

Cervical Cancer (CC) is a significantly prevalent disease in developing countries. Currently, targeted therapies are not a primary standard of care in CC. This information could be crucial for developing directed therapies and patient screening for biomarkers that would allow personalised treatment of CC. This systematic review aimed to estimate the prevalence of potential therapeutic targets such as the epidermal growth factor receptor (EGFR) and the PI3K/Akt/mTOR and Ras/Raf/MAPK pathways in patients with CC, identified through genomic and non-genomic testing. Studies were identified through an ad-hoc search strategy from the available on MEDLINE (Ovid), CENTRAL, LILACS, SCOPUS, through the Clinical Trial registry on Clinicaltrials.gov, International Clinical Trials Registry Platform, RENIS (Argentine National Registry of Health Research) and grey literature sources. We included 74 studies which represented a total pool of 7,862 participants. Forty-five studies informed mutations of EGFR, with a combined positivity rate of 53% (95%CI: 45%-60%; I2 = 95%). Twenty studies informed the presence of mutations in PIK3CA with a combined positivity rate of 30% (95%CI: 21%-39%; I2 = 96%). Twenty-three studies reported a mutation in Ras, with a combined positivity rate of 14% (95%CI: 8%-21%; I2 = 95%). Raf mutations were informed in six studies. Six studies informed the presence of Akt mutations, two studies informed mTOR mutations and only one study reported mutations of MAPK. The most frequently described therapeutic targets were EGFR, and the PIK3CA and Ras pathways, though inconsistency in positivity rates was significant. Our study did not allow the identification of any specific clinical characteristics that might explain the observed heterogeneity. Despite the overall good quality of the included studies, the applicability of these results to patients' general population with CC is still unclear.

Interplay Between EGFR and the Platelet-Activating Factor/PAF Receptor Signaling Axis Mediates Aggressive Behavior of Cervical Cancer

Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase widely expressed in cervical tumors, being correlated with adverse clinical outcomes. EGFR may be activated by a diversity of mechanisms, including transactivation by G-protein coupled receptors (GPCRs). Studies have also shown that platelet-activating factor (PAF), a pro-inflammatory phospholipid mediator, plays an important role in the cancer progression either by modulating the cancer cells or the tumor microenvironment. Most of the PAF effects seem to be mediated by the interaction with its receptor (PAFR), a member of the GPCRs family. PAFR- and EGFR-evoked signaling pathways contribute to tumor biology; however, the interplay between them remains uninvestigated in cervical cancer. In this study, we employed The Cancer Genome Atlas (TCGA) and cancer cell lines to evaluate possible cooperation between EGFR, PAFR, and lysophosphatidylcholine acyltransferases (LPCATs), enzymes involved in the PAF biosynthesis, in the context of cervical cancer. It was observed a strong positive correlation between the expression of EGFR × PAFR and EGFR × LPCAT2 in 306 cervical cancer samples. The increased expression of LPCAT2 was significantly correlated with poor overall survival. Activation of EGFR upregulated the expression of PAFR and LPCAT2 in a MAPK-dependent fashion. At the same time, PAF showed the ability to transactivate EGFR leading to ERK/MAPK activation, cyclooxygenase-2 (COX-2) induction, and cell migration. The positive crosstalk between the PAF-PAFR axis and EGFR demonstrates a relevant linkage between inflammatory and growth factor signaling in cervical cancer cells. Finally, combined PAFR and EGFR targeting treatment impaired clonogenic capacity and viability of aggressive cervical cancer cells more strongly than each treatment separately. Collectively, we proposed that EGFR, LPCAT2, and PAFR emerge as novel targets for cervical cancer therapy.

Nimotuzumab Combined With Irradiation Enhances the Inhibition to the HPV16 E6-Promoted Growth of Cervical Squamous Cell Carcinoma

Human papillomavirus (HPV) 16 E6 has been proved to increase the radiosensitivity and lead to the EGFR overexpression in cervical cancer cells. In this study, to investigate the inhibition of nimotuzumab-mediated EGFR blockade combined with radiotherapy, we established a C33A cervical squamous cell line overexpressed HPV16-E6 and a nude mouse model bearing these cell lines. The CCK-8 assay was used to detect the effects of various treatments on the proliferation of C33A cells. Flow cytometry was used to detect the rates of apoptosis and cell cycle arrest. Gene transcription and protein expression were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot, respectively. Immunohistochemical staining was used to evaluate protein expression in tumor tissue. We revealed that E6-overexpressing C33A cells grew faster and were more sensitive to radiotherapy than control cells in vitro and in vivo. The expression levels of EGFR, as well as those of downstream signaling molecules AKT and ERK 1/2, were significantly upregulated in C33A cells that overexpressed E6. We observed that nimotuzumab combined with radiotherapy could enhance the inhibition of C33A cell growth induced by E6, both in vitro and in vivo. We also observed enhanced effect after combination on G2/M cell cycle arrest and apoptosis in E6-overexpressing C33A cells. Furthermore, the combined therapy of nimotuzumab and radiation remarkably reduced the protein expression levels of EGFR, AKT, ERK 1/2 in vitro, and in vivo. In conclusion, HPV16 E6 expression is positively correlated with levels of EGFR, AKT, and ERK 1/2 protein expression. The combined treatment with nimotuzumab and radiotherapy to enhance radiosensitivity in E6-positive cervical squamous cell carcinoma was related to enhanced G2/M cell cycle arrest and caspase-related apoptosis.

F-box protein FBXO31 modulates apoptosis and epithelial-mesenchymal transition of cervical cancer via inactivation of the PI3K/AKT-mediated MDM2/p53 axis

AIMS

Cervical cancer (CC) is one of the most common malignant tumours in the world and a serious threat to women's health. The dysregulation of protein degradation mediated by F-box proteins is involved in tumorigenesis, and F-box protein FBXO31 has been reported to play an important role in various human cancers. However, the role of FBXO31 in CC remains unclear. This study aimed to investigate the function and underlying regulatory mechanism of FBXO31 in CC.

MAIN METHODS

In this study, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were used to measure target gene expression; the Cell Counting Kit-8, cell death ELISA, Transwell invasion assay, wound-healing assay and western blot were applied to assess cell viability, apoptosis, invasion, migration and epithelial-mesenchymal transition (EMT), respectively.

KEY FINDINGS

FBXO31 was expressed at a low level in 37 pairs of CC tissues and three types of CC cell lines. Overexpression of FBXO31 inhibited cell viability, invasion, migration, EMT and induced apoptosis in SiHa cells. FBXO31 promoted p53 activity through suppression of murine double minute 2 (MDM2) expression. Overexpression of MDM2 ameliorated the inhibitory effect of FBXO31 on SiHa cells, while the MDM2/p53 axis-specific inhibitor Nutlin-3a facilitated this inhibitory effect. Further, we confirmed that FBXO31 inactivated MDM2/p53 axis dependence on the phospholipid inositol 3-kinase (PI3K)/protein kinase B (AKT) signalling pathway.

SIGNIFICANCE

Collectively, our results reveal that FBXO31 down-regulates CC progression by blocking the PI3K/AKT-mediated MDM2/p53 axis, suggesting that FBXO31 may serve as a promising therapeutic target for CC treatment.

Elucidating the role of excision repair cross-complement group 1 in oral epithelial dysplasia and early invasive squamous cell carcinoma: An immunohistochemical study

Objectives:

Oral epithelial dysplasia (OED) is characterized by cellular alterations which have the proclivity of progressing to squamous cell carcinoma. Excision repair cross-complement group 1 (ERCC1) is one of the key proteins involved in nucleotide excision repair (NER) pathway. The expression of ERCC1 has been studied in colorectal, esophageal, ovarian and oral squamous cell carcinoma; but, very few studies have been done to apprehend the expression of ERCC1 in OED and early invasive squamous cell carcinoma (EISCC). The goal of this study is to evaluate the role of ERCC1 in OED and EISCC.

Materials and Methods:

Histopathologically diagnosed cases of moderate dysplasia (n = 10), severe dysplasia (n = 10) and EISCC (n = 10) were retrieved. 4 μ thick sections were cut from the formalin-fixed paraffin-embedded tissue blocks. The sections were immunohistochemically stained for ERCC1 following standard protocols. The expression of ERCC1 was evaluated semiquantitatively. Statistical analysis was carried out using Fischer's exact t-test.

Results:

The expression of ERCC1 was found to be strong (+3) in EISCC, moderate (+2) in severe dysplasia and mild (+1) in moderate dysplasia. Thus, the results were statistically significant between the three groups (P < 0.001).

Conclusion:

Disruption in the mechanisms that regulate cell cycle checkpoints and DNA repair mechanism results in genomic instability; these alterations might contribute to carcinoma. ERCC1 is essential to repair the DNA damage induced by various carcinogens. The present study shows significant difference in the expression of ERCC1 between EISCC and OED, which suggests ERCC1 could be used as one of the predictive markers.

MiRNAs in Radiotherapy Resistance of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors of the head and neck in Southeast Asia and southern China. Although the comprehensive treatment based on intensity-modulated radiation therapy improves outcomes, the five-year survival rate of NPC patients is low, and the recurrence remains high. Radiotherapy resistance is the main cause of poor prognosis in NPC patients. MicroRNAs (miRNAs) are a class of endogenous non-coding RNAs regulating various biological functions in eukaryotes. These miRNAs can regulate the development and progression of nasopharyngeal carcinoma by affecting the proliferation, apoptosis, movement, invasion and metastasis of NPC cells. The abnormal expression of miRNAs is closely related to radiotherapy sensitivity and prognosis of NPC patients, which can affect the transmission of related signaling pathways by regulating the expression of tumor suppressor genes and / or oncogenes, and therefore participate in radiotherapy resistance in nasopharyngeal carcinoma. Here, we review the mechanisms by which miRNAs may be involved in the radiotherapy resistance of nasopharyngeal carcinoma.

The role of autophagy and Beclin-1 in radiotherapy-induced apoptosis in thyroid carcinoma cells

BACKGROUND/OBJECTIVES

Thyroid cancer (TC), especially primary squamous cell carcinoma (SCC), is an aggressive malignant tumor which usually resists radiotherapy (RT). We wanted to understand the mechanism of incomplete response of RT in TC cells.

METHODS

SCC cell line SW579 cells were exposed to X-rays. Apoptosis and autophagy were measured by FACS; 3MA, inhibitor of autophagy, and Beclin-1 siRNA were used to investigate the effect of autophagy on radiation-induced TC cell apoptosis.

RESULTS

RT could induce TC cell apoptosis through death receptor as well as mitochondrial pathway. Radiotherapy also induces autophagy and increases expression of autophagy-associated proteins Beclin-1 and LC3. Moreover, inhibition of autophagy by 3MA and Beclin-1 siRNA enhanced radiation-induced apoptosis, through up-regulation of the expression of p53.

CONCLUSION

RT-induced autophagy resists apoptosis by the p53 pathway and an incomplete response to RT may be associated with autophagy in TC patients.

Positive crosstalk between EGFR and the TF-PAR2 pathway mediates resistance to cisplatin and poor survival in cervical cancer

Cisplatin-based chemoradiation is the standard treatment for cervical cancer, but chemosensitizing strategies are needed to improve patient survival. EGFR (Epidermal Growth Factor Receptor) is an oncogene overexpressed in cervical cancer that is involved in chemoresistance. Recent studies showed that EGFR upregulates multiple elements of the coagulation cascade, including tissue factor (TF) and the protease-activated receptors (PAR) 1 and 2. Moreover, many G protein-coupled receptors, including PARs, have been implicated in EGFR transactivation. However, the role of coagulation proteins in the progression of cervical cancer has been poorly investigated. Herein we employed cervical cancer cell lines and The Cancer Genome Atlas (TCGA) database to evaluate the role of EGFR, TF and PAR2 in chemoresistance. The SLIGKL-NH2 peptide (PAR2-AP) and coagulation factor VIIa (FVIIa) were used as PAR2 agonists, while cetuximab was used to inhibit EGFR. The more aggressive cell line CASKI showed higher expression levels of EGFR, TF and PAR2 than that of C33A. PAR2 transactivated EGFR, which further upregulated cyclooxygenase-2 (COX2) expression. PAR2-AP decreased cisplatin-induced apoptosis through an EGFR- and COX2-dependent mechanism. Furthermore, treatment of CASKI cells with EGF upregulated TF expression, while treatment with cetuximab decreased the TF protein levels. The RNA-seq data from 309 TCGA samples showed a strong positive correlation between EGFR and TF expression (P = 0.0003). In addition, the increased expression of EGFR, PAR2 or COX2 in cervical cancer patients was significantly correlated with poor overall survival. Taken together, our results suggest that EGFR and COX2 are effectors of the TF/FVIIa/PAR2 signaling pathway, promoting chemoresistance.

Prostaglandin EP2 receptor: Novel therapeutic target for human cancers (Review)

Prostaglandin E2 (PGE2) receptor 2 subtype (EP2), which is a metabolite of arachidonic acid that binds with and regulates cellular responses to PGE2, is associated with numerous physiological and pathological events in a wide range of tissues. As a stimulatory G protein‑coupled receptor, PGE2‑induced EP2 activation can activate adenylate cyclase, leading to increased cytoplasmic cAMP levels and activation of protein kinase A. The EP2 receptor can also activate the glycogen synthase kinase 3β and β‑catenin pathways. The present study aimed to review the roles of the EP2 receptor in tumor development, including immunity, chronic inflammation, angiogenesis, metastasis and multidrug resistance. Furthermore, the involvement of the EP2 receptor signaling pathway in cancer was discussed. Understanding the role and mechanisms of action of the EP2 receptor, and its importance in targeted therapy, may help identify novel methods to improve management of numerous types of cancer.