EGFR and HER2 expression in primary cervical cancers and corresponding lymph node metastases: implications for targeted radiotherapy

EGFR and HER2 expression in cervical cancer patients in Ibadan, Nigeria

Cervical cancer is a leading cause of cancer-related deaths in developing countries, including Nigeria where it is the second most common female malignancy. Studies from elsewhere have demonstrated the relationship between epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) and advanced cervical cancer. However, we are not aware of such studies in Nigerian patients. The main objective of the study was to determine the prevalence of EGFR or HER1 and HER2 protein expression in cervical cancers and to determine their impact on overall survival. Clinical data and formalin-embedded tissue blocks of 124 patients who presented in the Radiation Oncology Department, University College Hospital (UCH), from 2006 to 2015 and had their histological diagnosis at the Pathology Department, UCH were retrieved and analysed for EGFR and HER2 expression using immunohistochemistry. EGFR expression was analysed using the immunoreactivity score by Remmele and Stegner. HER2 was analysed using the Hercep® test kit guidelines. Survival analysis was done using Kaplan-Meier and Cox regression analysis. Missing data were reported as missing, not documented. EGFR (immunoreactivity score > 4) was overexpressed in 26.6% of the 124 cervical tissue samples tested. Most patients whose samples were positive for EGFR were young, had squamous cell carcinoma and advanced diseases. HER2 was overexpressed in two samples (1.6%). The 5-year overall survival rate of the patients was 28.3%. The 5-year survival rate of patients who were EGFR positive was 9.5% and 34.1% for those who were EGFR negative. Screening for EGFR should be considered in cervical cancer patients. HER2 was overexpressed in two cervical tissue samples in this study and may be of poor interest as a potential target in the management of cervical cancer patients. Large prospective multi-institutional studies should be considered to further explore the relationship between EGFR and survival in cervical cancer patients.

The Interplay of GPER1 with 17β-Aminoestrogens in the Regulation of the Proliferation of Cervical and Breast Cancer Cells: A Pharmacological Approach

The G-protein-coupled receptor for estrogen (GPER1) is a transmembrane receptor involved in the progression and development of various neoplasms whose ligand is estradiol (E2). 17β-aminoestrogens (17β-AEs) compounds, analogs to E2, are possible candidates for use in hormone replacement therapy (HRT), but our knowledge of their pharmacological profile is limited. Thus, we explored the molecular recognition of GPER1 with different synthetic 17β-AEs: prolame, butolame, and pentolame. We compared the structure and ligand recognition sites previously reported for a specific agonist (G1), antagonists (G15 and G36), and the natural ligand (E2). Then, the biological effects of 17β-AEs were analyzed through cell viability and cell-cycle assays in two types of female cancer. In addition, the effect of 17β-AEs on the phosphorylation of the oncoprotein c-fos was evaluated, because this molecule is modulated by GPER1. Molecular docking analysis showed that 17β-AEs interacted with GPER1, suggesting that prolame joins GPER1 in a hydrophobic cavity, similarly to G1, G15, and E2. Prolame induced cell proliferation in breast (MCF-7) and cervical cancer (SIHA) cells; meanwhile, butolame and pentolame did not affect cell proliferation. Neither 17β-AEs nor E2 changed the activation of c-fos in MCF-7 cells. Meanwhile, in SIHA cells, E2 and 17β-AEs reduced c-fos phosphorylation. Thus, our data suggest that butolame and pentolame, but not prolame, could be used for HRT without presenting a potential risk of inducing breast- or cervical-cancer-cell proliferation. The novelty of this work lies in its study of compound analogs to E2 that may represent important therapeutic strategies for women in menopause, with non-significant effects on the cell viability of cancer cells. The research focused on the interactions of GPER1, a molecule recently associated with promoting and maintaining various neoplasms.

Prevalence of HER2 overexpression and amplification in cervical cancer: A systematic review and meta-analysis

The reported rates of HER2 positivity in cervical cancer (CC) range from 0% to 87%. The importance of HER2 as an actionable target in CC would depend on HER2 positivity prevalence. Our aim was to provide precise estimates of HER2 overexpression and amplification in CC, globally and by relevant subgroups. We conducted a PRISMA compliant meta-analytic systematic review. We searched Medline, EMBASE, Cochrane database, and grey literature for articles reporting the proportion of HER2 positivity in CC. Studies assessing HER2 status by immunohistochemistry or in situ hybridization in invasive disease were eligible. We performed descriptive analyses of all 65 included studies. Out of these, we selected 26 studies that used standardized American Society of Clinical Oncology / College of American Pathologists (ASCO/CAP) Guidelines compliant methodology. We conducted several meta-analyses of proportions to estimate the pooled prevalence of HER2 positivity and subgroup analyses using geographic region, histology, tumor stage, primary antibody brand, study size, and publication year as moderators. The estimated pooled prevalence of HER2 overexpression was 5.7% (CI 95%: 1.5% to 11.7%) I2 = 87% in ASCO/CAP compliant studies and 27.0%, (CI 95%: 19.9% to 34.8%) I2 = 96% in ASCO/CAP non-compliant ones, p < 0.001. The estimated pooled prevalence of HER2 amplification was 1.2% (CI 95%: 0.0% to 5.8%) I2 = 0% and 24.9% (CI 95%: 12.6% to 39.6%) I2 = 86%, respectively, p = 0.004. No other factor was significantly associated with HER2 positivity rates. Our results suggest that a small, but still meaningful proportion of CC is expected to be HER2-positive. High heterogeneity was the main limitation of the study. Variations in previously reported HER2 positivity rates are mainly related to methodological issues.

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.

Chamuangone from Garcinia cowa leaves inhibits cell proliferation and migration and induces cell apoptosis in human cervical cancer in vitro

OBJECTIVES

To examine the effects of chamuangone on human cancer cell proliferation, migration and apoptosis.

METHODS

An MTT assay was used to study the effect of chamuangone on human cervical carcinoma cell growth. An in-vitro scratch migration assay was used to investigate the activity of cell motility after chamuangone treatment. Chamuangone-induced cell apoptosis in HeLa cells was determined using the apoptotic assay kit. The inhibitory activities of chamuangone were examined by ADP-Glo™ kinase assay. The GOLD docking algorithm was used to demonstrate the mechanism against tyrosine kinase of EGFR.

KEY FINDINGS

Chamuangone showed a strong inhibitory cell proliferation of HeLa cells with IC₅₀ values of 3.59 µm and effectively inhibited HeLa cell migration. In addition, chamuangone exhibited the apoptotic cell death induction in a time and dose-dependent manner. Finally, chamuangone also was tested for EGFR-TK inhibition activity. The IC₅₀ value of chamuangone was 2.85 nm, whereas the IC₅₀ value of gefitinib was 15.10 nm.

CONCLUSIONS

The above results confirm the inhibitory effects of chamuangone on HeLa cell proliferation and cell migration. In addition, chamuangone also induces cell apoptosis in HeLa cells. These findings indicate that chamuangone is a compound that is a potential chemotherapeutic agent.

Prognostic significance of the co-expression of EGFR and HER2 in adenocarcinoma of the uterine cervix

Prognostic factors and therapeutic targets are needed for the patients with cervical adenocarcinoma because they have a poor prognosis. Recently, co-expression of multiple receptor tyrosine kinases (RTKs) has been found to be associated with aggressive biological behavior and poor prognosis of several types of malignancy. To evaluate the significance of the expression of multiple RTKs in uterine cervical cancers, we examined the expression profile of RTKs (EGFR, HER2 and c-Met) and the correlation of their expression with clinicopathological features and prognosis of patients with cervical adenocarcinomas. AIS and adenocarcinoma showed strong expression of a single RTK (EGFR, HER2 or c-Met) on the cell membrane in 41 (77.4%) of 53 cases. Twenty (46%) of the 43 adenocarcinoma cases were positive for double or triple RTKs (P = 0.034). Positivity for EGFR and double positivity for EGFR and HER2 (EGFR+/HER2+/c-Met+ and EGFR+/HER2+/c-Met-) were significantly correlated with lymph node metastasis (P = 0.010 for single and P = 0.013 for double) and UICC stage (P = 0.021 for single and P = 0.007 for double). Positivity for HER2 was significantly correlated with tumor size (P = 0.029). Relapse-free survival (RFS) was significantly shorter in patients who were double positive for EGFR and HER2. Our results suggest that EGFR and HER2 are potential therapeutic targets and that their co-expression is a prognostic factor for cervical adenocarcinoma.

Association between vascular endothelial growth factor expression and lymph node metastasis in cervical cancer: A meta-analysis

AIM

The expression of vascular endothelial growth factor (VEGF) by cancer cells has been identified as a factor that is associated with lymph node metastasis (LNM) in some cancers, but an accurate description of the relation between VEGF and LNM in cervical cancer is lacking. We conducted a concurrent meta-analysis to investigate this issue.

METHODS

We searched PubMed and EMBASE for articles addressing the association between VEGF and cervical cancer. We used stata 12.0 and calculated the crude odds ratios (OR) and corresponding 95% confidence intervals (CI). Heterogeneity between the studies included was assessed by Cochran's Q-test.

RESULTS

Overall, 16 relevant studies with 426 cases and 751 controls were included in our study. The results demonstrated that cervical cancer patients with VEGF-positive expression had a 2.87-fold higher risk of LNM than patients without VEGF-positive expression (95%CI = 1.85-4.44, P < 0.001). Furthermore, subgroup analysis by ethnicity revealed that VEGF-positive expression could increase the risk of LNM in cervical cancer among Asian populations (OR = 2.55, 95%CI = 1.61-4.03, P < 0.001) and Caucasian populations (OR = 8.81, 95%CI = 2.78-27.88, P < 0.001). Moreover, subgroup analysis by country revealed that VEGF-positive expression could increase the risk of LNM in cervical cancer among Chinese populations (OR = 3.38, 95%CI = 2.18-5.25, P < 0.001) but not among Korean populations (P = 0.84) or Japanese populations (P = 0.06). Subgroup analysis based on sample size proved that VEGF-positive expression was statistically associated with LNM in a large sample group.

CONCLUSION

Our study revealed that VEGF-positive expression is related with higher risk of LNM in cervical cancer.

Microscopic lymph node tumor burden quantified by macroscopic dual-tracer molecular imaging

Lymph node biopsy (LNB) is employed in many cancer surgeries to identify metastatic disease and stage the cancer, yet morbidity and diagnostic delays associated with LNB could be avoided if non-invasive imaging of nodal involvement was reliable. Molecular imaging has potential in this regard; however, variable delivery and nonspecific uptake of imaging tracers has made conventional approaches ineffective clinically. A method of correcting for non-specific uptake with injection of a second untargeted tracer is presented, allowing tumor burden in lymph nodes to be quantified. The approach was confirmed in an athymic mouse model of metastatic human breast cancer targeting epidermal growth factor receptor, a cell surface receptor overexpressed by many cancers. A significant correlation was observed between in vivo (dual-tracer) and ex vivo measures of tumor burden (r = 0.97, p < 0.01), with an ultimate sensitivity of approximately 200 cells (potentially more sensitive than conventional LNB).

TACC3 is essential for EGF-mediated EMT in cervical cancer

The third member of transforming acidic coiled-coil protein (TACC) family, TACC3, has been shown to be an important player in the regulation of centrosome/microtubule dynamics during mitosis and found to be deregulated in a variety of human malignancies. Our previous studies have suggested that TACC3 may be involved in cervical cancer progression and chemoresistance, and its overexpression can induce epithelial-mesenchymal transition (EMT) by activating the phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal-regulated protein kinases (ERKs) signal transduction pathways. However, the upstream mechanisms of TACC3-mediated EMT and its functional/clinical importance in human cervical cancer remain elusive. Epidermal growth factor (EGF) has been shown to be a potent inducer of EMT in cervical cancer and associated with tumor invasion and metastasis. In this study, we found that TACC3 is overexpressed in cervical cancer and can be induced upon EGF stimulation. The induction of TACC3 by EGF is dependent on the tyrosine kinase activity of the EGF receptor (EGFR). Intriguingly, depletion of TACC3 abolishes EGF-mediated EMT, suggesting that TACC3 is required for EGF/EGFR-driven EMT process. Moreover, Snail, a key player in EGF-mediated EMT, is found to be correlated with the expression of TACC3 in cervical cancer. Collectively, our study highlights a novel function for TACC3 in EGF-mediated EMT process and suggests that targeting of TACC3 may be an attractive strategy to treat cervical cancers driven by EGF/EGFR signaling pathways.

Gene amplification and immunohistochemical expression of ERBB2 and EGFR in cervical carcinogenesis. Correlation with cell-cycle markers and HPV presence

Although the members of the epidermal growth factor receptor family ERBB2 and EGFR are important therapeutic targets in the treatment of malignant neoplasias, little is known about their role in cervical carcinogenesis. Our objective was to evaluate the dysfunction of ERBB2 and EGFR at the gene copy number and protein expression level in neoplastic lesions of the uterine cervix with the aim of obtaining information about its role in cervical carcinogenesis and their possible use as therapeutic targets in these diseases. We studied gene amplification and protein expression of ERBB2 and EGFR and their relationship with Ki67, p16 and p53 and HPV presence in 22 normal/benign (N/B) cervices, 20 low-grade squamous intraepithelial lesions (LSILs), 70 high-grade SILs (HSILs) and 32 invasive squamous cervical carcinomas (ISCCs). No cases showed selective amplification of ERBB2 or EGFR but corresponding chromosome-specific probes displayed chromosome 17 and 7 polyploidy associated with the grade of the lesion (p<0.0001 and p=0.004, respectively) and with the positive expression of Ki67 and p16 (p<0.01). Concurrent polyploidy for both chromosomes was statistically related (p<0.0001). ERBB2 immunohistochemical expression was not observed in any of the study cases except for one ISCC but EGFR was associated with higher-grade lesions (N/B plus LSIL 21.4% vs. HSIL plus ISCC 45.5%; p=0.007). No association was observed between EGFR expression and that of cell-cycle markers or HPV presence. Increased copy number of EGFR and ERBB2 is due to polyploidy of 7 and 17 chromosomes, this being a phenomenon associated with lesion severity and with an increase in the expression of cell-cycle markers. EGFR, but not ERBB2, is expressed in precursor lesions of squamous cervical neoplasia and is related to the neoplastic progression but not to proliferation marker expression and therefore ERBB2 and this calls into question the usefulness of ERBB2 as a therapeutic target.

Prognostic and risk factors in patients with locally advanced cutaneous squamous cell carcinoma of the trunk and extremities

55 patients with advanced cutaneous squamous cell carcinoma (CSCC) of the trunk and extremities were studied. A Tissue Microarray was constructed using immunohistochemistry to quantify expression of the HER family, E-cadherins, and podoplanin. Clinical and histopathological factors related to lymph node metastasis and prognosis were also established. Primary tumor positivity was 25.5% for EGFR, 87.3% for HER-3, and 48.1% for HER-4. Metastases were positive for EGFR in 41.7%, for HER-3 in 83.3%, and HER-4 in 43.5%. HER-2 was negative in all samples. Membrane E-cadherin and cytoplasmic E-cadherin were positive in 47.3% and 30.2% of primary tumors and 45.5% and 27.3% of metastases, respectively. Podoplanin was positive in 41.8% of primary tumors and 41.7% of metastases. Intratumoral lymphocytic infiltrate was associated with lymph node metastasis. Patients with T3 tumors had better cancer-specific survival (CSS) than those with T4 tumors; patients with no lymph node involvement had better CSS than patients with N1 tumors. Undifferentiated tumors and hyperexpression of podoplanin were negative prognostic indicators on multivariate analysis.

Usp18 regulates epidermal growth factor (EGF) receptor expression and cancer cell survival via microRNA-7

Epidermal growth factor receptor (EGFR) is involved in development and progression of many human cancers. We have previously demonstrated that the ubiquitin-specific peptidase Usp18 (Ubp43) is a potent regulator of EGFR protein expression. Here we report that the 3'-untranslated region (3'-UTR) of the EGFR message modulates RNA translation following cell treatment with Usp18 siRNA, suggesting microRNA as a possible mediator. Given earlier evidence of EGFR regulation by the microRNA miR-7, we assessed whether miR-7 mediates Usp18 siRNA effects. We found that Usp18 depletion elevates miR-7 levels in several cancer cell lines because of a transcriptional activation and/or mRNA stabilization of miR-7 host genes and that miR-7 acts downstream of Usp18 to regulate EGFR mRNA translation via the 3'-UTR. Also, depletion of Usp18 led to a decrease in protein levels of other known oncogenic targets of miR-7, reduced cell proliferation and soft agar colony formation, and increased apoptosis. Notably, all of these phenotypes were reversed by a specific inhibitor of miR-7. Thus, our findings support a model in which Usp18 inhibition promotes up-regulation of miR-7, which in turn inhibits EGFR expression and the tumorigenic activity of cancer cells.

Expression of phosphorylated histone H2AX (γ-H2AX) in normal and neoplastic squamous epithelia of the uterine cervix: an immunohistochemical study with epidermal growth factor receptor

The histone γ-H2AX is a marker of activated DNA damage and is overexpressed in different cancers and their precursor lesions, indicating a role in oncogenic transformation. Epidermal growth factor receptor (EGFR) is overexpressed in many kinds of epithelial neoplasms. This study aimed to determine whether immunohistochemical expression of γ-H2AX is involved in the progression of the morphological spectrum from normal squamous cervical epithelia (NE, n=33) to cervical intraepithelial neoplasia (CIN; CIN1, n=9; CIN2/3, n=33) and cervical invasive squamous cell carcinoma (ISCC, n=33), whether γ-H2AX expression follows the pattern of proliferation of atypical squamous cells as shown by EGFR immunoreactivity, and whether it is correlated with clinicopathologic variables in ISCC. Immunostaining for both the factors was scored semiquantitatively for moderate and strong intensities. Gamma-H2AX and EGFR expression, respectively, increased from NE and CIN1 to CIN2/3 and ISCCs significantly (P=0.0001, respectively). Gamma-H2AX reactivity was found in the nuclei of the cells of the upper epithelial levels and the cells of basal/parabasal type in variable quantities in NE and CIN; expression of γ-H2AX was seen in the nuclei of ISCC including keratinizing cells in horn pearls. EGFR staining was mainly membranous and noted in basal/parabasal cells in NE and atypically proliferating keratinocytes in CIN and nonkeratinizing cells of ISCC. In addition, immature squamous metaplasias were decorated by the antibodies used. Immunoscores for γ-H2AX and EGFR, respectively, did not differ between International Federation of Gynecology and Obstetrics stages I and II, keratinizing and nonkeratinizing ISCC, and CIN2/3 and ISCC. However, expression patterns were different for both the factors, suggesting their involvement in different biological mechanisms, with regard to γ-H2AX apart from proliferation. Overexpression of γ-H2AX in CIN2/3 and ISCC of the uterine cervix reflects the neoplastic transformation of cervical squamous epithelia in reaction to increased DNA-damage and supports the classification of dysplasia into low-grade squamous intraepithelial lesions and high-grade squamous intraepithelial lesions.

Epidermal growth factor receptor as a biomarker for cervical cancer

This review focuses on the different modes of expression of the epidermal growth factor receptor (EGFR). All methods used to assess EGFR expression are critically analyzed and insights into the use of inhibitors of EGFR for treatment of cervical cancer are discussed. Currently, expression of EGFR as a biomarker for prognosis or for treatment of cervical cancer is not defined for clinical use.

Mechanistic insight into the ability of American ginseng to suppress colon cancer associated with colitis

We have recently shown that American ginseng (AG) prevents and treats mouse colitis. Because both mice and humans with chronic colitis have a high colon cancer risk, we tested the hypothesis that AG can be used to prevent colitis-driven colon cancer. Using the azoxymethane (AOM)/dextran sulfate sodium (DSS) mouse model of ulcerative colitis, we show that AG can suppress colon cancer associated with colitis. To explore the molecular mechanisms of the anticancer effects of AG, we also carried out antibody array experiments on colon cells isolated at a precancerous stage. We found there were 82 protein end points that were either significantly higher (41 proteins) or significantly lower (41 proteins) in the AOM + DSS group compared with the AOM-alone (control) group. In contrast, there were only 19 protein end points that were either significantly higher (10 proteins) or significantly lower (9 proteins) in the AOM + DSS + AG group compared with the AOM-alone (control) group. Overall, these results suggest that AG keeps the colon environment in metabolic equilibrium when mice are treated with AOM + DSS and gives insight into the mechanisms by which AG protects from colon cancer associated with colitis.

Comparison of the epidermal growth factor receptor protein expression between primary non-small cell lung cancer and paired lymph node metastases: implications for targeted nuclide radiotherapy

Background

The knowledge of Epidermal growth factor receptor (EGFR) expression in metastases of NSCLC was limited. In receptor-mediated targeted nuclide radiotherapy, tumor cells are killed with delivered radiation and therapeutic efficiency is mainly dependent on the receptor expression. Thus, the level and stability of receptor expression in both primary tumors and corresponding metastases is crucial in the assessment of a receptor as target. The goal of this study was to evaluate whether EGFR is suitable as target for clinical therapy.

Methods

Expression of EGFR was investigated immunohistochemically in paired samples of lymph node metastases and corresponding NSCLC primary lesions (n = 51). EGFR expression was scored as 0, 1+, 2+ or 3+.

Results

Positive (1+, 2+ or 3+) EGFR immunostaining was evident in 36 of 47 (76.6%) analysed NSCLC primary tumors, and in 78.7% of the corresponding lymph node metastases. When EGFR expression is classified as positive or negative, discordance between the primary tumors and the corresponding metastases was observed in 5 cases (10.6%). EGFR overexpression (2+ or 3+) was found in 53.2% (25/47) of the NSCLC primary tumors and 59.6% of the corresponding metastases. Nine out of the 47 paired samples (19.2%) were discordant: Only three patients who had EGFR overexpression in the primary tumors showed EGFR downregulation (0 or 1+) in lymph node metastases, while six patients changed the other way around.

Conclusions

The EGFR expression in the primary tumor and the corresponding metastasis is discordant in about 10% of the patients. When overexpression is considered, the discordance is observed in about 20% of the cases. However, concerning EGFR overexpression in the primary tumors, similar expression in the metastases could be predicted with a reasonably high probability, which is encouraging for testing of EGFR targeted nuclide radiotherapy.

Molecular characterization of EGFR, PDGFRA and VEGFR2 in cervical adenosquamous carcinoma

BACKGROUND

Adenosquamous carcinoma of the uterine cervix is an infrequent but aggressive subtype of cervical cancer. A better understanding of its biological behaviour is warranted to define more accurate prognosis and therapeutic targets. Currently, the blockage of receptor tyrosine kinase (RTKs) activity is an efficient therapeutic strategy for many different cancers. The objective of this study was to investigate EGFR, PDGFRA and VEGFR2 RTKs overexpression and activating gene mutations in a cohort of 30 adenosquamous carcinomas of the uterine cervix.

METHODS

EGFR, PDGFRA and VEGFR2 immunohistochemistry was performed in all samples, followed by DNA isolation from the gross macroscopically dissection of the neoplastic area. Screening for EGFR (exons 18-21) and PDGFRA (exons 12, 14 and 18) mutations was done by PCR--single-strand conformational polymorphism (PCR-SSCP).

RESULTS

Despite the presence of EGFR immunohistochemical positive reactions in 43% (13/30) of the samples, no EGFR activating mutations in the hotspot region (exons 18-21) were identified. A silent base substitution (CAG>CAA) in EGFR exon 20 at codon 787 (Q787Q) was found in 17 cases (56%). All PDGFRA immunohistochemical reactions were positive and consistently observed in the stromal component, staining fibroblasts and endothelial cells, as well as in the cytoplasm of malignant cells. No activating PDGFRA mutations were found, yet, several silent mutations were observed, such as a base substitution in exon 12 (CCA>CCG) at codon 567 (P567P) in 9 cases and in exon 18 (GTC>GTT) at codon 824 (V824V) in 4 cases. We also observed the presence of base substitutions in intron 14 (IVS14+3G>A and IVS14+49G>A) in two different cases, and in intron 18 (IVS18-50insA) in 4 cases. VEGFR2 positivity was observed in 22 of 30 cases (73.3%), and was significantly associated with lack of metastasis (p=0.038).

CONCLUSION

This is the most extensive analysis of EGFR, PDGFRA and VEGFR2 in cervical adenosquamous carcinomas. Despite the absence of EGFR and PDGFRA activating mutations, the presence of overexpression of these three important therapeutic targets in a subset of cases may be important in predicting the sensitivity of adenosquamous carcinoma to specific anti-RTKs drugs.