Estrogen and progesterone receptors in head and neck cancer

Sex Differences in Otolaryngology: Focus on the Emerging Role of Estrogens in Inflammatory and Pro-Resolving Responses

Otolaryngology (also known as ear, nose, and throat (ENT)) diseases can be significantly affected by the level of sex hormones, which indicates that sex differences affect the manifestation, pathophysiology, and outcomes of these diseases. Recently, increasing evidence has suggested that proinflammatory responses in ENT diseases are linked to the level of sex hormones. The sex hormone receptors are present on a wide variety of immune cells; therefore, it is evident that they play crucial roles in regulating the immune system and hence affect the disease progression of ENT diseases. In this review, we focus on how sex hormones, particularly estrogens, regulate ENT diseases, such as chronic rhinosinusitis, vocal fold polyps, thyroid cancer, Sjögren’s syndrome, and head and neck cancers, from the perspectives of inflammatory responses and specialized proresolving mediator-driven resolution. This paper aims to clarify why considering sex differences in the field of basic and medical research on otolaryngology is a key component to successful therapy for both males and females in the future.

Association of Estrogen Receptor Alpha Expression With Survival in Oropharyngeal Cancer Following Chemoradiation Therapy

BACKGROUND

Oropharyngeal squamous carcinoma (OPSC) continues to increase in incidence secondary to human papillomavirus (HPV) infection. Despite the good overall prognosis for these patients, treatment with chemoradiation is associated with morbidity and treatment failure. Better predictors for disease outcome are needed to guide de-intensification regimens. We hypothesized that estrogen receptor α (ERα), a prognostic biomarker in oncology with therapeutic implications, might have similar utility in OPSC.

METHODS

To investigate associations among ERα and demographics, HPV status, and survival, we analyzed ERα mRNA expression of head and neck squamous carcinomas (HNSC) from The Cancer Genome Atlas (TCGA) and immunohistochemistry (IHC) of pretreatment biopsy specimens from an independent group of 215 OPSC patients subsequently treated with primary chemoradiation (OPSC-CR). Associations among variables were evaluated with Fisher exact tests and logistic regression; associations with survival were evaluated with log-rank tests and Cox proportional hazards regression.

RESULTS

Among 515 patients in TCGA, ERα mRNA expression was highest in HPV-positive OPSC. High ERα mRNA expression was associated with improved survival among those receiving chemoradiation (hazard ratio adjusted for HPV status = 0.44, 95% confidence interval = 0.21 to 0.92). In OPSC-CR, ERα was positive by IHC in 51.6% of tumors and was associated with improved overall, disease-specific, progression-free, and relapse-free survival (log-rank tests: P < .001, P < .001, P = .002, P = .003, respectively); statistically significant associations of ERα positivity with improved survival were maintained after adjusting for clinical risk factors including HPV status.

CONCLUSION

In two independent cohorts, ERα is a potential biomarker for improved survival that also may represent a therapeutic target in OPSC.

Expression of estrogen receptor alpha is associated with pathogenesis and prognosis of human papillomavirus-positive oropharyngeal cancer

Human papillomavirus (HPV) has been identified as a causative agent of cervical cancer and oropharyngeal cancer (OPC). Intriguingly, estrogen and HPV were shown to play synergistic roles in cervical carcinogenesis. We recently demonstrated that the apolipoprotein B mRNA-editing catalytic polypeptide 3 (APOBEC3, A3) family, which is inducible by estrogen, could lead to HPV DNA hypermutation and cause viral DNA integration. In the present study, we examined the relationships between estrogen-estrogen receptor α (ERα) and A3s in HPV-positive OPC. ERα expression was associated with HPV positivity in OPC biopsy samples using immunohistochemical analysis and reverse-transcription quantitative polymerase chain reaction. In addition, ERα was significantly associated with improved overall survival in HPV-positive OPC (hazard ratio, 0.26; p = 0.029). APOBEC3A (A3A) mRNA was induced by estrogen in HPV and ERα-positive OPC cells. Furthermore, A3A mRNA and protein expression were significantly higher in ERα-positive cases than in ERα-negative ones, among HPV-positive biopsy samples (p = 0.037 and 0.047). These findings suggest that A3A is associated with a good prognosis in ERα-positive OPC, and indicate the prognostic significance of ERα in HPV-positive OPC. This is the first study to demonstrate the prognostic role of ERα in HPV-positive OPC.

Expression pattern of estroprogestinic receptors in sinonasal inverted papilloma

Inverted papilloma (IP) is a locally destructive, benign neoplasm of the nose and paranasal sinuses with a high tendency for recurrence, a significant potential for malignancy, and an etiology that today is still uncertain. The expression of hormonal receptors in neoplastic tissues has been the focus of intensive research for its potential diagnostic, prognostic, and therapeutic significance. The aim of this study was to assess the potential estroprogestinic receptor expression in patients undergoing sinus surgery for IP. A retrospective study was carried out, on surgical specimens of 73 patients who underwent endoscopic sinus surgery for first manifestation of sinonasal IP (primitive IP group) and in 21 subjects who had developed a recurrence (relapsed IP group). The results of the immunohistochemical analysis of the first group showed the absence of receptor expression for PGR in all cases analyzed and the presence of a low positivity for ER in 11 cases (P > 0.082). Similarly, in the second group the results showed a low presence of ER receptors in 3 of the 21 cases (P > 0.068), while there was no evidence of PGR receptors in the examined samples. In addition, in 11 of the cases only 3 were considered positive (27.2%) showing a recurrence during follow-up (P > 0.068).

Our results suggest that the sinonasal IP is a benign tumor independent of estrogen and progesterone, and the receptors for these hormones are therefore unsuitable as predictors of relapse or possible prognostic indicators and therapeutic targets.

Comparison of the Effects of Cigarette Smoking on Male and Female Vocal Folds

OBJECTIVE

To investigate effects of smoking cigarette on male and female larynges and compare them.

METHOD

Eighteen adult Wistar Albino rats were included to study; 9 were male and 9 female. The exposure groups each contained 6 rats, and the control groups 3 rats. Six male constituted group 1 and 6 female constituted group 2. Group 1 and 3 were exposed to smoke. Group 2 and 4 were composed of 3 males and 3 females, respectively. Smoke from 10 cigarettes was delivered in each of the morning and afternoon daily for 1 month. At the end of 4 weeks, all rats were sacrificed and their larynges were evaluated histopathologically.

RESULTS

Microscobic evaluation of epithelium of vocal folds revealed no significant difference between study groups. There was also no difference between study and control groups. Subepitelial tissue showed no difference between study groups but angiogenesis and inflammation were higher in study groups. Epithelial analysis of false vocal folds showed significant difference between study groups. Female epithelium showed more hyperplastic and metaplastic changes.

CONCLUSION

Cigarette smoke damaged both the vocal folds and false vocal folds. The female false vocal folds were more susceptible to damage than the males.

Expression of estrogen and progesterone receptors across human malignancies: new therapeutic opportunities

Estrogen and progesterone receptors (ERs and PRs) are known for their prognostic as well as treatment predictive value in breast cancer. Although these receptors are differentially expressed in some other malignancies, and likely participate in the biology of those cancer types, the relevance to outcome and therapy is not well established. The use of ER as a highly effective therapeutic target in oncology was pioneered in breast cancer, and the lessons learned from its success could potentially benefit patients with several other malignancies in which hormone receptors are highly expressed. Indeed, there are several potent drugs available that target hormone receptors. These agents show incontrovertible evidence of benefit in patients with hormone receptor-positive breast cancer. It is conceivable that these drugs may have salutary effects in a variety of cancers other than those originating in the breast, based on the overexpression of hormone receptors in some patients, and the preclinical and clinical reports showing responses to these drugs in diverse cancers, albeit in small series or anecdotally. We therefore undertook a literature review in order to summarize the current data regarding the biologic and clinical implications of expression of estrogen and progesterone receptors in various malignancies and the possibilities for deployment of hormone manipulation beyond breast cancer.

The prognostic significance of estrogen receptor β in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the fifth most common cancer in the world. Although multimodal and targeted therapy is now used in therapeutic procedures, the survival of patients with HNSCC has remained unchanged over the last 30 years. A number of studies have demonstrated that the increased expression of intranuclear ERβ in breast, lung and colon cancer is a favorable prognostic marker associated with higher survival rates. However, the clinical significance of sex hormone receptors in HNSCC remains unclear. The current study aimed to assess the expression of ERβ in HNSCC immunohistochemically and investigate any possible association between ERβ expression, and clinical and histopathological factors, disease recurrence and patient survival. The present study included 174 patients (165 males and 9 females) with a median age of 60.8 years (range, 39–79) with HNSCC who were primary surgically treated between January 2000 and December 2006. Immunohistochemical reactions for ERβ demonstrated that 73 patients (42%) exhibited positive ERβ expression. Distribution of ERβ status among different head and neck subsites indicated that >40% of all negative cases were located in laryngeal primaries, while incidence of other sublocalization within positive cases was similar and comparable (P=0.04). Furthermore, a correlation was observed between ERβ immunopositivity and the survival of patients, with respect to the primary tumor site. Patients with ERβ positive oropharyngeal cancer had a survival rate of 35.3% at 5-years compared with 25% for patients with negative expression. However, ERβ status was not significantly correlated with any other clinical or histopathological parameter. After an average follow-up time of 38.5 months (range, 3–60 months), 54 patients (31.1%) had succumbed to disease recurrence while 50 (28.7%) succumbed to other causes. In conclusion, ERβ positivity indicates improved survival of patients with oropharyngeal cancer. Further research is required in order to implement novel therapeutic strategies.

Sex hormones in gender-specific risk for head and neck cancer: A review

Despite the fact that numerous researches have been carried out to prevent head and neck cancer (HNC) and treat those patients, there is no reduction in morbidity rate because the underlying molecular pathogenesis is still poorly understood. Endocrine microenvironment is another vital factor besides other traditional risk factors like tobacco smoking, infections, and alcohol. It has been proven that sex hormone receptors are also expressed in larynx and lungs, in addition to sex organs. Sex hormones play a vital role in gene expression involved in the plethora of biological and neoplastic processes. The role of sex hormones in HNC is still divisive and very few researches have been conducted to describe their role. So, this article is an effort to attract the attention of researchers, endocrinologists, pathologists, and clinicians toward the impending role of sex hormones, with special emphasis on progesterone, estrogen, and prolactin in HNC onset and progression, along with their therapeutic role.

Anti-cancer potential of a novel SERM ormeloxifene

Ormeloxifene is a non-steroidal Selective Estrogen Receptor Modulator (SERM) that is used as an oral contraceptive. Recent studies have shown its potent anti-cancer activities in breast, head and neck, and chronic myeloid leukemia cells. Several in vivo and clinical studies have reported that ormeloxifene possesses an excellent therapeutic index and has been well-tolerated, without any haematological, biochemical or histopathological toxicity, even with chronic administration. A reasonably long period of time and an enormous financial commitment are required to develop a lead compound into a clinically approved anti-cancer drug. For these reasons and to circumvent these obstacles, ormeloxifene is a promising candidate on a fast track for the development or repurposing established drugs as anti-cancer agents for cancer treatment. The current review summarizes recent findings on ormeloxifene as an anti-cancer agent and future prospects of this clinically safe pharmacophore.

Oestrogens and androgen receptors in oral squamous cell carcinoma

OBJECTIVE

To investigate the gender-related expressions of androgen (AR), estrogen alpha (ERα) and beta (ERβ) receptors and aromatase enzyme in oral squamous cell carcinomas (OSCC).

MATERIALS AND METHODS

A total of 60 cases of OSCC (30 from males and 30 from females) were retrieved and submitted to immunohistochemistry. Also, steroid expression was studied in two OSCC cell lines using Western blotting and immunofluorescence.

RESULTS

Immunohistochemistry demonstrated that ERβ was expressed in almost 40% of the cases and AR in 26%. Aromatase enzyme and ERα were less commonly expressed. Only AR presented statistically significant differences between genders. Western blotting and immunofluorescence analysis demonstrated that ERβ was abundantly expressed in the nuclei of both cell lines and aromatase enzyme presented a cytoplasmic expression.

CONCLUSION

The detection of steroid hormones, especially ERβ, can indicate a role of these proteins in the process of carcinogenesis of some OSCC. Further studies of the mechanisms involved may provide important biological information regarding therapeutic approaches.

Expression of sexual hormones receptors in oral squamous cell carcinoma

Sexual hormones play an important role in expression of genes involved in a wide variety of biological and neoplastic processes. The information on Estrogen Receptors (ER) expression in non-target tissues is very few and, in particular, the studies in head and neck tumors are still controversial. Recent studies analyzed the role of Tamoxifen (TAM) on Oral Squamous Cell Carcinoma (OSCC) lines in relation to the presence/absence of ER. The purpose of the present study was to evaluate the expression of sexual hormones receptors mRNAs, in particular Estrogen Receptor alpha (ERα) and Androgen Receptor (AR) mRNA in OSCC tissues. The study group comprised 20 samples of OSCC, harvested from 20 otherwise healthy subjects (14 males and 6 females, mean age 58.2y, range 38-74). The control group was formed by 20 samples of normal mucosa harvested around the margins of the specimens (at least 1 cm from the lesion margins). Estrogens Receptor alpha (Era) and Androgen Receptor (AR) mRNA expressions were analyzed by RT-PCR carried out on total RNAs extracted from both cancerous and healthy tissues. Obtained data were evaluated by Shapiro-Walk normality test and compared by Student's t test. Results with p<0.05 were considered statistically significant. AR transcripts were less expressed in OSCC specimens than in healthy tissues, while levels of ERα transcripts significantly increased in tumor samples. These preliminary data show different expression patterns of AR and ERα mRNAs in malignant tissues of oral mucosa and could suggest an involvement of these sexual hormones in oral cancer.

Head and neck squamous cell carcinoma in pregnant women

BACKGROUND

The aim of this study was to investigate oral cancer in pregnant women, a rare but therapeutically challenging patient subset.

METHODS

After institutional review board approval, an EMERSE search was used to identify all women treated at the University of Michigan from 1998 to 2010 with head and neck squamous cell carcinoma (HNSCC) during pregnancy. This identified 4 patients with tongue cancer. Biomarkers and human papillomavirus (HPV) were assessed by immunohistochemistry and multiplex PCR/mass spectrometry, respectively.

RESULTS

Two patients responded well to therapy and are alive more than 10 years after diagnosis; 2 patients died of disease. All tumors overexpressed EGFR and Bcl-xL, 3 of 4 overexpressed c-Met, both tumors that progressed overexpressed p53. All tumors were negative for HPV, p16, estrogen receptor, progesterone receptor, and HER-2.

CONCLUSIONS

Biomarkers of aggressive tumors (high EGFR, c-Met; high Bcl-xL-low p53) did not correlate with outcome. Additional studies are needed to determine whether perineural invasion, delay in diagnosis, and p53 overexpression are factors in poor survival.

Microsurgery in juvenile nasopharyngeal angiofibroma: a lateronasal approach with nasomaxillary pedicled flap

Thirty-four consecutive juvenile nasopharyngeal angiofibromas, mainly stage II or III, were removed using a transnasomaxillary approach with good tumor control and without complications or sequelae. A pedicled nasomaxillary osteomucocutaneous flap is lifted through a lateronasal skin incision, and reflected laterally to open the nasal fossa and the maxillary sinus. This approach is an improvement on the conventional approach of lateral rhinotomy, which entails nasomaxillary skeletal loss. The approach ensures early and direct exposure of the root of the tumor and its vascular peduncle and also allows removal of tumors with intracranial extradural extensions.

Cross-talk between estrogen receptor and epidermal growth factor receptor in head and neck squamous cell carcinoma

PURPOSE

This study aimed to characterize estrogen receptor expression and signaling in head and neck squamous cell carcinoma (HNSCC) cell lines and patient tissues, and to evaluate estrogen receptor and epidermal growth factor (EGF) receptor (EGFR) cross-activation in HNSCC.

EXPERIMENTAL DESIGN

Estrogen receptor expression and signaling in HNSCC cell lines were assessed by immunoblotting. In vitro proliferation and invasion were evaluated in HNSCC cell lines in response to estrogen receptor and EGFR ligands or inhibitors. Estrogen receptor and EGFR protein expression in patient tissues was assessed by immunohistochemical staining.

RESULTS

Phospho-mitogen-activated protein kinase (P-MAPK) levels were significantly increased following combined estrogen and EGF treatment. Treatment of HNSCC cells with estrogen and EGF significantly increased cell invasion compared with either treatment alone, whereas inhibiting these two pathways resulted in reduced invasion compared with inhibiting either pathway alone. EGFR (P = 0.008) and nuclear estrogen receptor alpha (ER alpha(nuc); P < 0.001) levels were significantly increased in HNSCC tumors (n = 56) compared with adjacent mucosa (n = 30), whereas nuclear estrogen receptor beta (ER beta(nuc)) levels did not differ (P = 0.67). Patients with high ER alpha(nuc) and EGFR tumor levels had significantly reduced progression-free survival compared with patients with low tumor ER alpha(nuc) and EGFR levels (hazards ratio, 4.09; P = 0.01; Cox proportional hazards). In contrast, high ER beta(nuc) tumor levels were not associated with reduced progression-free survival alone or when combined with EGFR.

CONCLUSIONS

ER alpha and ER beta were expressed in HNSCC, and stimulation with estrogen receptor ligands resulted in both cytoplasmic signal transduction and transcriptional activation. Estrogen receptor and EGFR cross-talk was observed. Collectively, these studies indicate that estrogen receptor and EGFR together may contribute to HNSCC development and disease progression.

Sex hormone receptor levels in laryngeal carcinoma: a comparison between protein and RNA evaluations

The larynx is a secondary sex organ, and the hormone dependence of laryngeal carcinomas is considered an interesting matter of speculation. However, while tumors of other secondary sex organs, including the prostate, breast, and endometrium, have been recognized as hormone-dependent cancers, the laryngeal carcinomas are still subject to controversy. In this study, samples from 15 laryngeal carcinomas obtained at the time of surgery were assayed for specific estrogen alpha, progesterone, and androgen receptor expression, both at mRNA and protein levels. Detectable levels of specific estrogen and progesterone receptors, 53.3 and 73.3%, respectively, were found in the tumors. This positive detection by immunohistochemical analysis was higher in tumors than in normal mucosa adjacent to the tumor areas and was correlated with the absence of metastatic lymph nodes. No androgen receptor protein was detected in any sample analyzed, even if quantitative RT-PCR revealed high mRNA levels specific for this receptor. A strict correspondence between protein and mRNA hormone receptor levels was not found. This is in agreement with the transcriptional and protein synthesis mechanisms, and it is also compatible with the complex larynx tumorigenesis.

Aromatase expression in normal human oral keratinocytes and oral squamous cell carcinoma

Aromatase is the enzyme that catalyzes the conversion of androgen to oestrogen. Aromatase expression in extra-gonadal sites and local oestrogen synthesis play an important role in the physiological conditions and in the growth of certain neoplasms.

OBJECTIVE

The purpose of this study was to investigate aromatase expression in oral keratinocytes and oral squamous cell carcinoma (SCC).

DESIGN

Immunocytochemistry and RT-nested PCR were used to detect aromatase protein and mRNA expression in primary human oral epithelial cell culture and in an oral SCC cell line. Immunohistochemistry was used to detect aromatase protein expression in frozen and archival human tissue sections of normal oral epithelium and oral SCC.

RESULTS

Cytoplasmic immunostaining was found in normal oral keratinocytes and SCC cells in culture. The common coding region of aromatase mRNA was detected in the oral keratinocytes derived from five different normal individuals and in the SCC cell line. However, there were variations in aromatase exon 1 expression among normal oral keratinocyte samples. Cytoplasmic staining was found in normal oral epithelium and well-differentiated oral SCC but not in poorly differentiated oral SCC by immunohistochemistry.

CONCLUSION

Aromatase was expressed in normal oral keratinocytes and oral SCC both in cell culture and in tissues, indicating local oestrogen synthesis in normal and neoplastic conditions of oral epithelium.

Effects of tamoxifen on human squamous cell carcinoma lines of the head and neck

Tamoxifen (TAM) is a well-tolerated compound in the treatment of breast cancer and is primarily considered to act by competition with estrogen receptors (ER). Here we investigated the in vitro efficacy and potentially underlying mechanisms of TAM in established cell lines of squamous cell carcinomas of the head and neck (SCCHN). Using proliferation and apoptosis assays the antitumor activity of TAM in five SCCHN and the breast carcinoma line MCF-7 (positive control) was determined. MCF-7 was more sensitive to low-dose TAM (below 1 microM), whereas SCCHN showed significant growth inhibition at higher TAM concentrations (5-10 microM). Growth curve analysis and apoptosis assays were indicative for a cytostatic effect of low-dose TAM and high-dose TAM led to cell loss by apoptosis in sensitive SCCHN. In order to further characterize the observed antitumor effects we determined the amount of steroid hormone receptors with the dextran-coated charcoal method and immunocytochemistry. In addition, production of transforming growth factor (TGF-)-alpha, -beta1 and -beta2 was measured by ELISA, and protein kinase C (PKC) activity was assessed with a radioligand assay. Except MCF-7, none of the SCCHN lines was positive for ER. TAM caused decreased TGF-alpha and increased TGF-beta levels in MCF-7, but not in SCCHN supernatants. Furthermore, the antiestrogen reduced PKC activity in MCF-7, but not in SCCHN. In the present in vitro system, the observed antitumor activity of high-dose TAM in SCCHN cannot be explained by estrogen antagonism, alterations of TGF-alpha/beta levels or decreased PKC activity.

Detection of estrogen receptor by immunohistochemistry in pulmonary adenocarcinoma

BACKGROUND

The distinction between primary adenocarcinoma and metastatic breast carcinoma in the lung is important for therapeutic purposes. There is a good deal of morphologic overlap between primary pulmonary adenocarcinoma and breast carcinoma metastatic in the lung. Many diagnosticians rely upon the presence of estrogen receptor (ER) in tumors of the lung in women in order to make a pathologic diagnosis of metastatic breast carcinoma. There are conflicting data in the literature regarding the presence of ER in lung carcinomas. In this study, we examined primary lung adenocarcinomas with monoclonal antibodies to two different clones to ER (clone 6F11 and clone 1D5), and progesterone receptor by the immunoperoxidase method in order to ascertain if ER is detectable in primary lung adenocarcinomas.

METHODS

Twenty-five resected solitary pulmonary nonmucinous bronchioalveolar carcinomas (15 female, 10 male) and 20 resected solitary pulmonary adenocarcinomas of no special type (12F, 8 mol/L) were studied by the immunohistochemical method using heat-induced epitope retrieval. Immunostaining was semiquantitated, and positive results included nuclear staining for ER and progesterone receptor. All of these tumors were documented as primary pulmonary adenocarcinomas clinically and pathologically.

RESULTS

Nuclear ER was seen only with the 6F11 clone, in 56% of the bronchioalveolar type and 80% of the no special type. No nuclear ER was seen in carcinomas utilizing the 1D5 clone. There was no progesterone receptor detectable in carcinomas.

CONCLUSIONS

Estrogen receptor is present in the majority of lung adenocarcinomas, and detection of ER in lung adenocarcinomas is dependent upon the antibody clone that is used. Epitope recognition may account for the differences in immunoreactivity between these two antibodies, although a cross-reactive antibody reaction cannot be completely excluded. Further study is warranted to discern the nature of the 6F11 clone immunoreactivity with nuclei of lung adenocarcinomas. The clinical significance and ramifications of ER in pulmonary adenocarcinomas remain unknown. Caution should be exercised by clinicians and pathologists in accepting a diagnosis of metastatic breast carcinoma in lung based on the presence of ER detected by clone 6F11.

Steroid hormone receptors in parotid gland cystadenolymphoma (Warthin's tumour)

The aetiopathogenesis of cystadenolymphoma is mostly unknown. Cystadenolymphomas have a significantly higher incidence in the male than the female population. This might be as a result of endocrine dependency in this kind of tumour. The purpose of the present study was to determine the sex hormone receptor status in cystadenolymphoma. Tissue samples of cystadenolymphoma, pleomorphic adenoma and normal samples of the parotid gland were examined immunohistochemically for oestrogen and progesterone receptors. Progesterone-positive cells could be found in the salivary duct system of normal glands and in the epithelial components of cystadenolymphomas. There was no evidence for the presence of oestrogen receptor in any sample studied. The evidence of progesterone receptors in cystadenolymphoma may implicate a potential role of endocrine factors in the development of this tumour.

Human larynx expresses isoforms of the oestrogen receptor

Commercially available enzyme immunoassays (EIAs) were used for oestrogen (ER) and progesterone (PR) receptor determination in the cytosol fraction of 118 human larynx cancer specimens and in the corresponding histologically proven non-malignant tissues. Fifty-one ER positive cancerous samples had corresponding non-cancerous tissues also expressing the receptor. A high resolution isoelectric focusing (IEF) technique followed by immunoblotting with the H222 anti-ER monoclonal antibody was used to evaluate the presence of ER isoforms in the 51 ER positive human larynx cancer specimens and in their corresponding non-malignant tissues. In both tissues, four ER isoforms were detected, with isoelectric points (pI) similar to those obtained in breast and endometrium carcinomas (6.1, 6.3, 6.6 and 6.8). A significant difference in the expression of ER isoforms between cancerous and non-cancerous tissue was found; precisely, the 94.1% of the ER positive non-malignant specimens co-expressed the four isoforms while they were detected in only the 35.5% of the malignant specimens (P < 0.0001 by Fisher's exact test). In larynx cancer, the concentration values of ER and PR did not correlate, nevertheless tumours co-expressing the four ER isoforms had PR levels significantly higher than those which did not (P = 0.02 by Mann-Whitney Wilcoxon sum rank test). To investigate the possibility that the isoforms of the monomeric 4S form of the ER (those with pI 6.3, 6.6, and 6.8) could dimerise, a cold agarose gel electrophoresis technique was used on IEF-separated ER isoforms. In summary, the evidence shows that all the isoforms are able to form homodimers and that the isoforms at pI 6.3 and 6.8 are able to dimerise with that at pI 6.6 but, under the same experimental conditions, they do not form the 6.3/6.8 heterodimer. It was concluded that: (1) the four isoforms of the ER are co-expressed by the non-malignant human larynx and the cancer loses the capacity to express some of them; (2) the complete complement of ER isoforms (all four) is needed for PR expression; (3) the monomeric 4S isoform with pI 6.6 has the capacity to form homo- and heterodimers, while the remaining two are only able to homodimerise.

Estrogen receptors in parotid tumors

A regulatory role for estrogen in the growth of salivary gland tumors has been hypothesized. In the current study we attempted to establish whether or not benign and malignant parotid tumor cells express estrogen receptors. Immunohistochemical studies were performed with samples of tissue from 72 patients with benign tumors and 26 patients with malignant tumors originating in the parotid gland. Replicate tissue sections were stained with two sets of reagents specific for the receptors. There was no immunohistochemical evidence for the presence of estrogen receptors in any specimen examined. In contrast, cells in tissue sections from a breast cancer control were consistently positive for estrogen receptor using the same techniques. These observations show that the estrogen receptor concentration in parotid tumors is below the level required for visualization by immunohistochemical techniques. Thus, it is unlikely that this receptor plays a major role in regulating parotid tumor growth.

Androgen and progesterone receptors in oral carcinoma

Androgen (AR) and progesterone (PgR) receptors were measured in 18 samples of normal oral mucosa and of squamous cell carcinoma of the floor of the mouth or the tongue. In a given mean concentration of R1881 (Methyltrienolone) of 8.4 nM in the carcinoma and of 7.9 nM in the normal mucosa, we measured a mean androgen receptor level in the carcinoma smaller than 1.08 fmol/mg protein (< 0.034 fmol/microgram DNA). There was a significant difference (p < 0.05) from the androgen receptor level in the normal mucosa (2.2 fmol/mg protein, 0.082 fmol/microgram DNA). In this experiment, in only 41.2% did we find any PgR receptor in the carcinoma whereas all normal tissue contained PgR, the concentration varied between 0.1 and 3.0 fmol/mg protein (0.01-0.09 fmol/microgram DNA).

Immunohistochemical and immunoradiometric evaluations of total cathepsin D in human larynx

By using a commercially available immunoradiometric technique (Cath-D-IRMA, Cis BioInt.) the distribution of total cathepsin D (cath-D) in 30 malignant and in the corresponding histologically-proven non-malignant fragments obtained from lymph node negative patients suffering from larynx cancer was investigated. In both tissues the oestrogen and progesterone receptors were also assayed. In 17 out of the 30 samples, the cath-D was also assayed by immunohistochemistry using the M1G8, a mouse monoclonal antibody raised against cath-D (Cis BioInt.). Our data indicate that cath-D is present in prismatic cells of the normal laryngeal epithelium and in the cancerous cells. In cancerous larynx, the outer cell layer of large tumour nests showed the highest degree of immunoreactivity, while fibroblasts and inflammatory cells always showed a very faint staining. Cathepsin D levels were significantly higher (P < 0.0001) in the cancerous fragments (with a mean of 33 +/- 3.4 pmol/mg protein) than in the corresponding non-cancerous specimen (with a mean of 20.8 +/- 2 pmol/mg protein). A significant positive association (P < 0.001) between cath-D and progesterone receptor (PR) concentration values in the cancerous larynx was observed; accordingly, tumours expressing PR had significantly (P = 0.0005) higher cath-D levels than the tumours which did not contain the receptor. In contrast, such a relationship was absent in the non-malignant specimens. As regard the oestrogen receptor, no significant relationship between this and cath-D was observed. We conclude that cath-D measured by IRMA in tissue cytosols is mainly derived from cancerous cells, the contribution from fibroblasts and inflammatory cells being negligible. Cathepsin D overexpression and association with the PR in the malignant part of the larynx could indicate a possible role of the receptor in the biology of this disease.

Expression of cathepsin D in malignant and in the corresponding non-malignant node-negative laryngeal samples: correlation with receptors for androgen, glucocorticoid, oestrogen and progesterone

A standard immunoradiometric technique was used to investigate the distribution of the intracellular aspartic proteinase cathepsin D in 33 malignant and in the corresponding histologically-proven non-malignant fragments obtained from lymph node negative patients suffering from larynx cancer. In both tissues the androgen, glucocorticoid, oestrogen and progesterone receptors were also assayed. Our data indicate that cathepsin D was present in both tissues, with level significantly higher (P < 0.0001) in the cancerous fragments (with a mean of 33 +/- 3.4 pmol/mg protein) than in the corresponding non-cancerous specimen (with a mean of 20.8 +/- 2 pmol/mg protein). A significant positive association (P < 0.001) between cathepsin D and PR concentration values in the cancerous larynx was observed; accordingly, tumours expressing PR had significantly (P = 0.0005) higher cathepsin D levels than the tumours which did not contain the receptor. In contrast, such a relationship was absent in the non-malignant specimens. As regards the other steroid receptors, no significant relationship between them and cathepsin D was observed. We conclude that cathepsin D may have a role also in laryngeal carcinoma and that its association with the PR could indicate a possible role of the receptor in the biology of this disease.

Epidermal growth factor receptors and oestrogen receptors in the head and neck

We report a pilot study of the levels of epidermal growth factor receptors (EGFR) in normal and neoplastic tissues of the head and neck. Specimens from 20 consecutive patients undergoing major head and neck surgery showed that squamous cell carcinomas had detectable but widely varying levels of EGFR. EGFR expression was greater in normal salivary gland tissue than in benign salivary neoplasms. Oestrogen receptors were not detected in clinically significant amounts in any of the tumours assayed.

Steroid receptor status in malignant and non-malignant larynx

We investigated for the first time the relationships among all the different steroid receptor classes and between steroid receptor status and lymph node involvement in laryngeal carcinoma. Androgen (AR), oestrogen (ER), progesterone (PR) and glucocorticoid (GR) receptors were assayed in the high-speed soluble fraction and in the nuclear extract from 73 carcinomas of the larynx. Forty-one, 26, 15, and 13 tumours expressed cytosolic GR, ER, AR, and PR, respectively, while 33, 26, 13 and 13 biopsies were nuclear-positive for GR, ER, AR, and PR, respectively. Data obtained in histologically-proven non-cancerous larynx (N = 20) compared to those obtained in the malignant specimens showed a significant loss of ER and PR in cancerous larynx over that in the non-cancerous tissue. Lymph node metastases were evaluated in only 53 of the 73 patients and they were noted in 22 cases (41.5%). No significant relationships were found either among the different classes of steroid receptors or between steroid receptors and lymph node involvement. Despite the apparent absence of any interrelationships among the different receptors or tendency towards metastasis, the presence of steroid receptors would justify the use of hormonal manipulations which could be effective in the management of this disease.

Antitumor activity of naltrexone and correlation with steroid hormone receptors

We have evaluated the opiate peptide antagonist, naltrexone, for its effectiveness as an antitumor agent. For this evaluation, we tested the effect of naltrexone given daily in the diet on the growth of established 7,12-dimethylbenz(a)anthracene-induced mammary tumors. Tumors continued to grow actively in rats fed chow diet only (control group). In contrast, the naltrexone-supplemented diet (75 mg/kg diet) significantly decreased the size of the established mammary tumors in rats over the 25 day observation period, resulting in an average decrease in tumor volume by approximately 23% compared with their sizes at the beginning of the treatment. Tumor regression occurred in 70% of the rats. Tumors that respond to naltrexone showed appreciable amounts of estrogen and progesterone receptors while unresponsive tumors were negative for estrogen and progesterone receptors. For the first time, we report that naltrexone can regress established mammary tumors and that the inhibitory effect of naltrexone appears to be restricted to the hormonally responsive mammary tumors.

Receptors for epidermal growth factor and steroid hormones in primary laryngeal tumors

The authors investigated the presence of epidermal growth factor (EGF-R), estrogen (ER), progesterone (PR), and androgen (AR) receptors in 42 laryngeal squamous cell carcinomas and 20 normal laryngeal mucosa specimens. EGF-R were expressed in all tumor specimens analyzed, with significantly higher levels in tumor samples compared with normal mucosa (P less than 0.05). The immunohistochemical study demonstrated the presence of EGF-R in basal and parabasal cells of normal mucosa and in most of the cancer cells. There was no correlation between EGF-R and tumor localization or T classification. On the other hand, the authors did find an interesting correlation between EGF-R levels and grading, EGF-R levels being significantly higher in G3 than in G1-G2 tumors. Moreover, the three patients whose tumors expressed the highest EGF-R levels had disease recur within 8 months. Among tumor specimens, 9.5%, 35.7%, and 9.5% expressed very low but detectable ER, PR, and AR levels, respectively. No statistically significant difference was found between the levels of steroid receptors in the tumor and normal mucosa specimens, and neither was there any correlation of ER, PR, and AR with the pathologic findings. The authors' results suggest that the EGF-R system may play a role in regulating the growth of laryngeal cancer. Additional studies should demonstrate whether, as in other tumor types, EGF-R expression may have prognostic significance in human laryngeal cancer.

Cyclic-AMP binding proteins in the head and neck

Results are presented of a preliminary study in which cAMP binding activity was measured in 34 specimens from a variety of head and neck sites. A wide range of cAMP binding protein levels was detected in all tissues assessed. There appeared to be a subgroup of parotid adenomas with increased cAMP binding activity. The biological significance of these proteins remains to be determined and their relationship to tumour growth in the head and neck is likely to be complex.

Antineoplastic properties of Maharishi-4 against DMBA-induced mammary tumors in rats

Maharishi-4 (M-4), an ayurvedic food supplement, was tested for anticarcinogenic and anticancer properties against 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in rats. The 6% M-4-supplemented diet protected DMBA-induced carcinogenesis by reducing both tumor incidence and multiplicity during initiation and promotion phases. The control animals who developed tumors when supplemented with M-4 diet for four weeks showed tumor regression in 60% of cases. There was no significant difference in the food intake or weight gain in rats who were on M-4-supplemented diet compared to control group. Possible mechanisms of action of M-4 are discussed.

Progesterone receptors in carcinomas of the upper aerodigestive tract

This study had three major goals: (1) to vigorously verify the presence of progesterone receptors in squamous cell carcinoma of the upper aerodigestive tract (HN-SCC). Antiprogesterone receptor monoclonal antibodies revealed a distinct band at approximately 120 kilodaltons in samples taken from two of four patients with HN-SCC. These results illustrate that progesterone receptor in HN-SCC has the same molecular weight as progesterone receptor in normal human uterus and human breast cancer. Steroid specificity and saturability results support the evidence that it is true progesterone receptors that are measured and not other receptors or sex steroid-binding globulins; (2) to confirm the biochemical function of progesterone receptors in HN-SCC by assessing the binding of progesterone receptor to acceptor sites on chromosomes in the nucleus; and (3) to establish the clinical significance of progesterone receptor measurement. Patients with positive assays were more likely to be free of disease a mean of 6 months after resection. We used logistic regression to account for site of primary disease, grade of tumor, and stage of disease. This logistic regression was significant with a p = 0.014. Patients with a binding index greater than 2 (19 of 73 patients) were 4.34 times more likely to be free of disease than patients with negative assays.

Estrogen and progesterone receptors in gallbladder cancer

Cancerous tissues from 21 patients with primary gallbladder cancer were examined immuno-histochemically for the presence of receptors for estrogen (ER) and progesterone (PGR). ER and PGR, localized in the nucleus, were evident in 52.4 per cent and 0 per cent of the patients, respectively. Furthermore, ER and PGR were positive only in the cytoplasm of cancer cells in 28.6 per cent and 66.7 per cent, respectively. There was a higher tendency of moderately- and poorly-differentiated adenocarcinoma to have an ER-positive rate than well-differentiated adenocarcinoma. With respect to the relationship between ER and sex, ER-positive nuclei were observed in 8 of 14 women (57.1 per cent) and 3 of 7 men (42.9 per cent), but the difference between the two was not significant due to the small number of subjects. These result suggested that gallbladder cancers with ER in the nuclei may respond to antihormone therapy.

Determination of sex steroid receptor in human basal cell carcinoma

The role of estrogens in the development of skin cancer is controversial. Sex steroids have a profound effect on the epidermis and epidermal appendages. Estradiol in pharmacologic doses has been reported to stimulate basal cell carcinoma in an animal model. Sex hormones act by means of a specific protein receptor. In this study we used a specific, highly sensitive monoclonal antibody to evaluate sex steroid receptors in human basal cell carcinoma. No estrogen or progesterone receptor protein was detected in the basal cell tumor, despite clear positive control tissues. We conclude that these sex steroid receptors are not present in significant amounts to mediate a direct effect in basal carcinoma.

Estimation of oestrogen and progesterone receptors in chronic rhinitis

The turbinates of 38 patients with chronic rhinitis were examined biochemically for oestrogen and progesterone receptors. Low levels of oestrogen-receptor-like activity (1-20 fmol/mg protein) were found in 50% of patients of both sexes. Progesterone receptor activity was also weak (1-16 fmol/mg protein) but was present only in 5 female patients. Immunocytochemical assay failed to demonstrate focal areas of oestrogen receptor activity. One juvenile nasopharyngeal angiofibroma was negative for both oestrogen and androgen receptors. Other possible mechanisms of hormonal action are considered.

Steroid hormone receptors in laryngeal carcinoma

The larynx has long been shown to be a target organ for androgenic steroids in both women and men, and specific androgen receptors have been determined in normal laryngeal mucosa and in laryngeal carcinoma tissue. In this study, samples from 21 primary laryngeal carcinomas, from 4 recurrent laryngeal carcinomas and from 1 cervical metastasis of laryngeal carcinoma were obtained at the time of surgery to assay specific androgen, estrogen, and progesterone receptors. Specific androgen receptors were found in 8 samples (31%). The level of receptors varied from 1.7 femtomoles (fmol) per milligram to 7.3 fmol/mg cytosol protein. Detectable levels of specific estrogen receptors were found in 18 samples (69%) and progesterone receptors in 8 of the 15 samples studied (53%). There was no apparent correspondence with donors' sex, since samples from both females and males contained all kinds of receptors. We know that antiestrogen inhibits the growth of squamous carcinoma cells lines positive for estrogen receptors in vitro and that this effect is reversible with the appropriate hormone. Thus, the relatively high percentage of estrogen and progesterone receptors found in laryngeal carcinoma tissue may open new aspects in the treatment of laryngeal carcinoma with antihormones.

Androgen stimulation and laryngeal development

Androgen-induced changes in laryngeal growth patterns were studied using a sheep animal model. Forty-eight lambs were divided into eight treatment groups. Lambs in seven of the groups were castrated at birth, while lambs in the eighth group served as an intact (noncastrated) control. Six groups were then treated with varying doses of testosterone and dihydrotestosterone, while the seventh served as a castrated, nontreated control. All animals were killed and gross dissections of the larynges were performed. Thirty-four linear and angular measurements were obtained from each larynx. The mean superior thyroid horn separation showed the most dramatic androgen-induced effect (p = 0.023). Laryngeal anterior-posterior diameter, superior thyroid horn height, posterior thyroid cartilage width, thyroid cartilage angle, and vocal process to arytenoid base distances all demonstrated positive dose-response relationships. Hypoandrogenic levels appeared to have an inhibitory effect upon laryngeal growth when compared to castrated controls.