Epidermal growth factor receptor expression in squamous cell lung carcinomas: an immunohistochemical and gene analysis in formalin-fixed, paraffin-embedded material

Integrating the DNA damage and protein stress responses during cancer development and treatment

During evolution, cells have developed a wide spectrum of stress response modules to ensure homeostasis. The genome and proteome damage response pathways constitute the pillars of this interwoven 'defensive' network. Consequently, the deregulation of these pathways correlates with ageing and various pathophysiological states, including cancer. In the present review, we highlight: (1) the structure of the genome and proteome damage response pathways; (2) their functional crosstalk; and (3) the conditions under which they predispose to cancer. Within this context, we emphasize the role of oncogene-induced DNA damage as a driving force that shapes the cellular landscape for the emergence of the various hallmarks of cancer. We also discuss potential means to exploit key cancer-related alterations of the genome and proteome damage response pathways in order to develop novel efficient therapeutic modalities. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Is there a relationship between c-erbB-1 and c-erbB-2 amplification and protein overexpression in NSCLC?

In order to analyse the genetic abnormalities and protein expression of c-erbB-1 and -2, we have performed fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) in resected non-small cell lung carcinoma (NSCLC). By IHC (106 patients), 11% of the patients were positive both for c-erbB-1 and -2 protein expression and 47% negative for both proteins. FISH (69 patients) showed a balanced disomy for both c-erbB-1 and -2 in 38%, all other cases had genetic abnormalities in at least one of both genes. c-erbB-2 gene was amplified in less than 10% of the tumours and c-erbB-1 gene was never amplified. c-erbB-2 protein overexpression was observed in only three out of the six cases showing c-erbB-2 amplification. The negative predictive value (NPV) of IHC for gene abnormalities was high for both markers. Median survival time (MST) was respectively of 76 and 174 weeks for patients with or without c-erbB-2 overexpression. Patients with c-erbB-2 amplification had a shorter survival: 125 weeks versus 165 weeks. MST was respectively of 109 and 196 weeks for patients with or without EGFR overexpression and patients with EGFR gene abnormalities had also a shorter survival with MST 136 weeks versus 189 weeks. These differences were not significant. In conclusion, if the majority of NSCLC showed genetic abnormalities in the c-erbB-1 and/or c-erbB-2 gene receptor, amplification could be observed only in a few tumours and was not strictly correlated with protein expression. Finally, survival of patients expressing EGFR and/or c-erbB-2 was slightly shorter.

Epidermal growth factor receptor as a target to improve treatment of lung cancer

Despite considerable efforts to reduce tobacco use, lung cancer remains the most common cancer in both men and women. Recent advances in radiation therapy and chemotherapy for lung cancer have yielded encouraging results, but survival in patients with locally advanced non-small-cell lung cancer (NSCLC) remains poor. As more and more molecular changes and their importance in malignant tissues continue to be characterized, approaches to target those aberrant pathways are being actively explored. The epidermal growth factor receptor (EGFR) is commonly overexpressed in NSCLC, particularly squamous cell carcinoma, and has been implicated in the development and progression of this disease, although a clear correlation with prognosis has not been established. Several different strategies have been developed to target and block the EGFR and its downstream effects, and some of them have been intensively studied in preclinical and clinical studies as a single-agent approach or in combination with radiation therapy or chemotherapy. In this article, we review the role of EGFR in lung cancer, as well as preclinical and clinical data on strategies to interfere with EGFR signaling alone or in combination with chemotherapy, radiation, or both.

Sensitive differential detection of genetically related mycobacterial pathogens in archival material

A polymerase chain reaction (PCR) assay targeted to the immunogenic protein MPB64 gene was used to detect members of the Mycobacterium tuberculosis complex, and an outward-primed PCR (OPPCR) designed on the IS6110 element allowed differentiation between Mycobacterium bovis and Mycobacterium tuberculosis. Additionally, the amplification of IS1110 and 16S ribosomal RNA sequences combined with a dot blotting assay were able to differentially detect Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium paratuberculosis. The validity of the experimental procedure was tested on reference material and formalin-fixed paraffin-embedded samples from patients with tuberculosis, sarcoidosis, or Crohn disease. We demonstrated mycobacterial DNA in 59 of 75 cases with histologic lesions typical of tuberculosis; we detected M tuberculosis and M paratuberculosis in 6 of 25 sarcoidosis cases and in 7 of 20 Crohn disease specimens, respectively. The proposed diagnostic procedure is directly applicable to archival material and allows differentiation of genetically related mycobacterial pathogens in more detail than other molecular methods. It provides a tool for the diagnostic study of tuberculosis, sarcoidosis, and Crohn disease.

"High risk" HPV types are frequently detected in potentially malignant and malignant oral lesions, but not in normal oral mucosa

Studies on the involvement of the human papillomavirus (HPV) in initiation and progression of oral neoplasia have generated conflicting results. The observed discrepancy is attributable mainly to the varying sensitivity of the applied methodologies and to epidemiologic factors of the examined patient groups. To evaluate the role of HPV in oral carcinogenesis, we analyzed 53 potentially neoplastic and neoplastic oral lesions consisting of 29 cases of hyperplasia, 5 cases of dysplasia, and 19 cases of squamous cell carcinomas, as well as 16 oral specimens derived from healthy individuals. A highly sensitive nested polymerase chain reaction (PCR) assay was used, along with type-specific PCR, restriction fragment length polymorphism analysis, dot blotting, and nonisotopic in situ hybridization. Nested PCR revealed the presence of HPV DNA in 48 of the 53 (91%) pathologic samples analyzed, whereas none (0%) of the normal specimens was found to be infected. Positivity for HPV was independent of histology and the smoking habits of the analyzed group of patients. At least one "high risk" type, such as HPV 16, 18, and 33, was detected by type-specific PCR in 47 (98%) infected specimens, whereas only 1 (2%) squamous cell carcinoma was solely infected by a "low risk" type (HPV 6). HPV 16 was the prevailing viral type, being present in 71% of infected cases. Single HPV 16 and HPV 18 infections were confirmed by restriction fragment length polymorphism. HPV 58 was detected by dot blotting in three hyperplastic lesions. HPV positivity and genotyping were further confirmed, and the physical status of this virus was evaluated by nonisotopic in situ hybridization. Diffuse and punctate signals, indicative of the episomal and integrative pattern of HPV infection, were observed for low- and high-risk types, respectively. Our findings are suggestive of an early involvement of high-risk HPV types in oral carcinogenesis.

Differential expression of epidermal growth factor receptor in melanocytic tumours demonstrated by immunohistochemistry and mRNA in situ hybridization

Differential expression of the epidermal growth factor receptor (EGFR) has been reported in melanocytic lesions. To evaluate these differences in EGFR expression in melanocytic tumours, formalin-fixed, paraffin embedded sections from 33 benign melanocytic neoplasms and 77 cutaneous melanomas were analysed for EGFR protein and mRNA expression using immunohistochemistry and mRNA in situ hybridization. The majority of benign and malignant lesions expressed EGFR at both protein and mRNA levels. In 7% (7/100) samples, mRNA but not protein expression was observed. Overall, a higher proportion of cells expressed EGFR protein in malignant lesions compared with benign lesions (P = 0.06), and the intensity of mRNA expression was higher in the malignant tumours (P < 0.001). No significant differences in EGFR protein or mRNA expression with tumour progression within the malignant lesions were seen. These results indicate that EGFR mRNA and protein expression is common to benign and malignant melanocytic lesions, and that an overall increase in expression is associated with malignant transformation. However, differential EGFR expression between in situ melanomas and invasive or metastatic lesions was not observed.

Expression of epidermal growth factor receptor in urinary bladder cancer metastases

Bladder cancers frequently exhibit an increased number of epidermal growth factor receptors (EGFR) in comparison to normal urothelium. The EGFR could potentially be a target for toxic conjugates. The aim of our study was to compare the expression of EGFR in metastases with concurrent or primary tumour in the urinary bladder using immunohistochemical techniques and a monoclonal antibody. Tumour material from 20 patients was investigated. The majority (13/20) of the metastases were homogeneously stained and showed a moderate to strong membranous staining for EGFR. The expression of EGFR in primary bladder tumours and metastases was similar. There was no indication that tumour tissue exposed to chemotherapy or radiation had a decreased number of EGFR. Targeting of the EGFR thus seems potentially applicable to metastatic disease.

The epidermal growth factor receptor and its ligands as therapeutic targets in human tumors

The epidermal growth factor receptor (EGFR) is detected on many non-haematopoietic tissues and is frequently overexpressed in human tumors. With its ligand, TGF-alpha, it forms a well-defined autocrine growth loop. Several clinical approaches, using EGFR as a therapeutic target, are being investigated, particularly monoclonal antibodies combined with chemotherapy, and pharmacological inhibition of downstream components of the EGFR signaling pathway.

Molecular and immunohistochemical study of class I growth factor receptors in squamous cell lung carcinomas

The class I growth factor receptor family includes epidermal growth factor receptor, i.e. c-erbB-1, c-erbB-2 and c-erbB-3 molecules. These receptors have a significant sequence homology and play an important role in cell growth and differentiation. To further investigate their implication in squamous cell lung carcinomas (SqCLCs), we studied the protein expression by immunohistochemistry and examined for possible gene amplification by a novel semi-quantitative differential polymerase chain reaction (DPCR) technique. Expression of c-erbB-1, c-erbB-2 and c-erbB-3 was present in 65%, 28% and 10% respectively, of 40 SqCLCs cases. Seven of the 11 cases that expressed c-erbB-2, as well as all 4 c-erbB-3 expressing cases, also stained with the anti-c-erbB-1 mAb. Expression of c-erbB-1, but not of c-erbB-2 or c-erbB-3, correlated with the grade of tumor differentiation (100%, 64% and 36% positive cases of well, moderately and poorly differentiated cases respectively, p < 0.003). In addition, c-erbB-1 expression correlated with the presence of regional lymph node metastases within the moderately differentiated group. The c-erbB-1 gene was amplified in 11/40 (28%) cases, all of which overexpressed c-erbB-1 protein, while c-erbB-2 gene amplification was detected in only one case. There was no c-erbB-3 gene amplification in any of the 40 SqCLCs cases. These findings suggest that c-erbB-1, c-erbB-2 and c-erbB-3 receptors do not have a common role and are of different physiological importance, at least at the stage of clinically overt tumor in human SqCLCs.

Molecular analysis of p53 gene in laryngeal premalignant and malignant lesions. p53 protein immunohistochemical expression is positively related to proliferating cell nuclear antigen labelling index

This study was undertaken in order to investigate the molecular nature of the p53 gene in 19 laryngeal squamous cell carcinomas and dysplasias. Moreover, we have examined the possible relationship between proliferating cell nuclear antigen (PCNA) expression and p53 protein detection status in 42 laryngeal premalignant and malignant lesions in which 14 of the 19 samples used in the molecular study were included. p53 gene analysis was performed with the single-strand conformation polymorphism technique. PCNA was stained with the peroxidase/antiperoxidase immunohistochemical method using the monoclonal antibody PC-10. Data from previous work concerning p53 expression was used. We found that 9 of 12 of the immunohistochemically p53 positive (+) cases had mutations in exons 5 or 6. In the remaining immunohistochemically p53(+) and p53 negative (-) specimens there was no indication of sequence alterations. Furthermore, we did not observe any deletions in the chromosomal region 17p31.1 which encodes exons 4-8 of the p53 gene. The PCNA labelling index (LI) increased progressively with p53 protein detection status (percentage of cells immunohistochemically positive for p53). The difference between the group with the higher percentage of p53(+) cells and the others was statistically significant. These data show that although there is a discrepancy between immunohistochemical demonstration of p53 and molecular analysis, a large proportion of the former harbours the mutant form of the protein. In addition, p53 overexpression is positively correlated with PCNA LI, a finding which accompanies tumour progression.

Epidermal growth factor receptor (EGFr) expression in non-small cell lung carcinomas correlates with metastatic involvement of hilar and mediastinal lymph nodes in the squamous subtype

Epidermal growth factor receptor (EGFr) levels were evaluated in paraffin-embedded tumour specimens of non-small cell lung cancer (NSCLC) from 176 patients who underwent surgical resection. The EGFr expression was evaluated by immunocytochemical assay using a monoclonal antibody which recognises the external domain of the receptor. EGFr immunoreactivity was significantly higher in squamous than in non-squamous cell carcinomas (P = 0.0009). Hilar and/or mediastinal nodal involvement was found in 29 of 105 (27.4%) squamous cancers, and in this group of patients, the mean of EGFr positive cells was significantly higher than that of patients without nodal involvement (P = 0.01). No significant correlations were found between the expression of EGFr and other clinicopathological or biological parameters such as T-status, grading, proliferative activity. EGFR is suggested to represent a useful indicator of nodal metastasis in NSCLC.