Receptor Staining Intensity Research Articles

Immunohistochemical study on localized oestrogen receptors following subacute oral administration of 3-methylmorphine (codeine) in ovaries of albino Wistar rats

The immunohistochemistry of localized oestrogen receptors following subacute oral administration of dihydrocodeine in ovaries of albino Wistar rats was studied. The specific objectives were; to determine the distribution of oestrogen receptors in the ovaries using immunohistochemical expression method and to evaluate oestrogen staining intensity using Image J statistical software. The twenty 20 rats were divided into 4 groups of five rat each. The control (group A) rats received distilled water per body weight while group B-D received 30, 60 and 90 mg/kg dihydrocodeine orally for 28 days. Animals were anesthetized using ketamine injection and abdominopelvic incision was made. The ovaries were harvested and processed using histochemistry. Photomicrographs were obtained using light microscope and arm scope. Oestrogen staining intensity was analysed using analysis of variance (ANOVA), followed by Post Hoc test using Image J statistical software. The results obtained show that the ovarian follicles had high staining intensity with monoclonal oestrogen receptor antibodies in group I, while group II showed moderate-high staining intensity. Group III showed low intensity of staining of oestrogen in the ovaries of the rats, while group IV showed low staining intensity of oestrogen in the ovarian follicle of albino rats. Oestrogen receptor staining intensity decreased in the ovaries of the treatment groups, which was significant at p<0.05. This study concludes that Dihydrocodeine caused significant decrease (p <0.013) in localized estrogen receptor in the ovaries of albino rats.

PACAP and PAC1 Receptor Expression in Human Insulinomas

Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with widespread occurrence and diverse functions. PACAP binds to specific PAC1 and non-specific VPAC1/2 receptors. PACAP is considered as a growth factor, as it plays important roles during development and participates in reparative processes. Highest concentrations are found in the nervous system and endocrine glands, where several functions are known, including actions in tissue growth, differentiation and tumour development. Therefore, we have investigated expression of PACAP and its receptors in different tumours, including those of endocrine glands. We showed earlier that PACAP and PAC1 receptor staining intensity decreased in pancreatic ductal adenocarcinoma. In the present study we aimed to investigate alterations of PACAP and PAC1 receptor in human insulinoma and compared the immunostaining pattern with samples from chronic pancreatitis patients. We collected perioperative and histological data of patients who underwent operation because of insulinoma or chronic pancreatitis over a five-year-long period. Histology showed chronic pancreatitis with severe scar formation in pancreatitis patients, while tumour samples evidenced Grade 1 or 2 insulinoma. PACAP and PAC1 receptor expression was studied using immunohistochemistry. Staining intensity was very strong in the Langerhans islets of normal tissue and discernible staining was also observed in the exocrine pancreas. Immunostaining intensity for both PACAP and PAC1 receptor was markedly weaker in insulinoma samples, and disappeared from chronic pancreatitis samples except for intact islets. These findings show that PAC1 receptor/PACAP signalling is altered in insulinoma and this suggests a possible involvement of this system in tumour growth or differentiation.

PROGNOSTIC IMPACT OF LOW ESTROGEN AND PROGESTERONE POSITIVITY IN LUMINAL B (HER2 NEGATIVE) BREAST CANCER.

SUMMARY – Luminal B (HER2 negative) subtype is the most diversiform type of breast cancers, with a high Ki-67 proliferation index (>20%) or/and low progesterone (PR; <20%) with various intensity and distribution of hormone receptors. Considerable difference has also been noticed in disease outcome, wherefore there is the need for a more detailed classification of this tumor subtype. The clinical and pathologic parameters of 147 luminal B (HER2 negative) breast cancers were examined. The expression of hormone receptors in correlation with other prognostic factors and disease outcome was analyzed by Kaplan-Meier curves and multivariate Cox regression analysis. The Kaplan-Mayer analysis showed that low positivity of estrogen (ER) and PR receptors in tumors was associated with a significantly worse disease outcome (overall survival (ER), p=0.020; disease free survival (ER), p=0.019; overall survival (PR), p=0.026; disease free survival (PR), p=0.038)), unlike Ki-67, which did not show a statistically significant connection (overall survival, p=0.343; disease free survival, p=0.322). The intensity of receptor staining and Ki-67 relative to other histopathologic prognostic factors showed a statistically significant correlation solely with histologic grade of tumor. By using the Cox regression model, PR proved to be an independent prognostic factor for overall survival (p=0.004) and disease free survival (p=0.029). The luminal B (HER2 negative) breast cancer with low expression of hormone receptors, independent of the Ki-67 proliferation index, and in correlation with a higher histologic grade, could be a unique subtype of cancer.

Effect of injectable medroxyprogesterone acetate and etonogestrel implants on GABA-A and serotonin receptors in white and gray matter of the brain: experimental study in rats

The aim of this study was to evaluate the time-dependent effect of progesterone-only contraceptives on the brain and to obtain an improved understanding of mood disorders experienced under this medication. A total of 66 Wistar albino rats were divided into three groups: etonogestrel (ENG) implant (group 1, n = 30); depot medroxyprogesterone acetate (MPA)-injectable (group 2, n = 30); and control (group 3, n = 6) groups. Groups 1 and 2 were each divided into five subgroups, which were examined every 10 d for up to 50 d after medication administration, to evaluate its time-dependent effect. There was no difference in terms of gamma-aminobutyric acid (GABA) and serotonin immunohistochemical staining in white and gray matter among the subgroups of group 1. In group 2, there was a significant decrease in serotonin receptor staining intensity in white and gray matter on day 50, when compared to the control group (p = 0.041). When the subgroups of group 2 were compared, there was a significant decrease in serotonin receptor staining intensity in white and gray matter on days 40 and 50 when compared to day 10. In conclusion, we showed that ENG and MPA have no effect on apoptosis and GABA-A receptors in the brain. We also showed that MPA has time-dependent effects on serotonin receptors, which may be a possible mechanism involved in mood disorders during long-term usage of injectable progesterone-only contraceptives.

Aromatase inhibitors affect vaginal proliferation and steroid hormone receptors

Women with breast cancer who are treated with aromatase inhibitors often experience vaginal atrophy symptoms and sexual dysfunction. This work aims to study proliferation and the presence and distribution of steroid hormone receptors in vaginal biopsies in relation to vaginal atrophy and vaginal pH in women with breast cancer who are on adjuvant endocrine treatment and in healthy postmenopausal women. This is a cross-sectional study that compares postmenopausal aromatase inhibitor-treated women with breast cancer (n = 15) with tamoxifen-treated women with breast cancer (n = 16) and age-matched postmenopausal women without treatment (n = 19) or with vaginal estrogen therapy (n = 16). Immunohistochemistry was used to study proliferation and steroid hormone receptor staining intensity. Data was correlated with estrogen and androgen levels, vaginal atrophy scores, and vaginal pH. Aromatase inhibitor-treated women had a lower grade of proliferation, weaker progesterone receptor staining, and stronger androgen receptor staining, which correlated with plasma estrone levels, vaginal atrophy scores, and vaginal pH. Women with aromatase inhibitor-treated breast cancer exhibit reduced proliferation and altered steroid hormone receptor staining intensity in the vagina, which are related to clinical signs of vaginal atrophy. Although these effects are most probably attributable to estrogen suppression, a possible local inhibition of aromatase cannot be ruled out.

Immunohistochemical Changes in 5 Respiratory Nuclei after Bilateral Carotid Body Denervation (CBD) in Sprague Dawley Rats

Bilateral CBD in rat has no effect on CO2 sensitivity but elicits hypoventilation 1–2 d post‐CBD followed by a return to baseline values 7–8 d post‐CBD. To investigate the neural mechanisms driving the recovery of breathing after CBD, we compared NK1 receptor staining intensity on neuronal membranes from 5 different respiratory nuclei (solitary tract, NTS; dorsal motor, DMV; hypoglossal, nXII; nucleus ambiguous, NA; pre‐botzinger complex, PBC). Brain tissue was obtained from sham (n=1) and CBD animals sacrificed 4–5 (n=1), and &gt;;21 d (n=2) post‐CBD. Optical density (OD) measurements of NK1 in NTS, DMV, and nXII in the sham rat (0.91, 0.96, 0.80 OD, respectively) were similar to rats sacrificed after 21 d post CBD (0.84, 0.96, 0.74 OD, respectively). The rat sacrificed 4–5 d post‐CBD had less intense NK1 staining in the NTS (0.68 OD), DMV (0.77 OD), and nXII (0.65 OD) relative to the other group of rats. The sham rat had lower OD values in the NA (0.54 OD) and PBC (0.70 OD) than rats sacrificed after 21 d post‐CBD (0.93 and 0.93 OD, respectively). These preliminary data suggest that CBD causes a down‐regulation, and recovery from CBD due to up‐regulation of the NK1 receptor. Remaining tissue sections from the same animals will be used to compare AMPA type 2, NMDA type 1, the serotonin transporter, and 5HT2A receptor staining intensities in the same respiratory nuclei. Supported by NIH HL097033

Transient receptor potential vanilloid 1 mediates nerve growth factor‐induced bladder hyperactivity and noxious input

To explore the role of transient receptor potential vanilloid 1 (TRPV1) in the excitatory effects of chronic administration of nerve growth factor (NGF) on bladder-generated sensory input and reflex activity. To explore new therapeutic targets for bladder dysfunction. Wild-type (WT) and TRPV1 knockout (KO) mice received daily intraperitoneal injections of NGF (1 µg/10 g) or saline for a period of 4 days, during which time thermal sensitivity was evaluated daily. On the 5th day, mice were anaesthetized and cystometries were performed. The frequency, amplitude and area under the curve (AUC) of bladder reflex contractions were determined. c-Fos expression was evaluated on L6 spinal cord sections of WT and TRPV1 KO mice treated with saline or chronic NGF by immunohistochemistry. TrkA receptor staining intensity was determined in L6 spinal cord sections and respective dorsal root ganglia of WT and TRPV1 KO mice. Repeated administration of NGF induced thermal hypersensitivity in WT but not in TRPV1 KO mice. The frequency of bladder contractions of saline-treated WT and TRPV1 KO mice was similar, the values respectively being 0.45 ± 0.12/min and 0.46 ± 0.16/min. Treatment with NGF enhanced bladder reflex activity in WT mice to 1.23 ± 0.41/min (P < 0.05). In NGF-treated KO mice, the frequency of bladder contractions was 0.60 ± 0.05/min. Irrespective of treatment, no differences were observed in the amplitude of bladder contractions of WT and TRPV1 KO mice. The AUC was significantly increased in NGF-treated WT-mice, when compared with saline-treated WT-mice. No changes were found in AUC of saline-treated and NGF-treated TRPV1 KO mice. Chronic administration of NGF resulted in a significant increase of spinal c-Fos expression in WT mice (P < 0.05 vs KO animals), but not in TRPV1 KO animals. TrkA expression was similar in WT and TRPV1 KO mice. NGF-induced bladder overactivity and noxious input depend on the interaction of NGF with TRPV1. The lack of bladder overactivity in TRPV1 KO mice treated with NGF does not represent loss of TrkA expression. TRPV1 is essential for NGF-driven bladder dysfunction and represents a bottleneck target in bladder pathologies associated with NGF up-regulation.

Effects of Short-Term Finasteride on Apoptotic Factors and Androgen Receptors in Prostate Cancer Cells

We explored the molecular correlates of the effect of finasteride on prostate tissue in patients undergoing radical prostatectomy. Patients undergoing radical prostatectomy for localized prostate cancer were eligible for study. After providing informed consent patients were randomized to receive 5 mg finasteride or placebo daily for at least 30 days before surgery. At surgery prostate tissue was harvested from the surgical specimen and sent for analysis. Tissue samples were analyzed for the pro-apoptotic factors caspase-3, caspase-7 and IGFBP-3. Samples were also analyzed for the tumor suppressor/proto-oncoproteins bcl-2, p53 and p21. Finally, tissues were analyzed for androgen receptor density and insulin growth factor-1. A total of 22 study and 20 placebo samples were collected and analyzed. Negligible staining for bcl-2 or caspase-3 was noted in each group. Statistical differences were not observed for bcl-2, p53, p21 or insulin growth factor-1 between the groups. There was a statistically significant difference in caspase-7 and IGFBP-3. A mean of 77% and 99.9% of cells stained for caspase-7 in the treatment and placebo groups, respectively (p = 0.007). In 3 patients caspase-7 staining disappeared completely and it was decreased by 70% and 50% in 1 patient each. Mean intensity staining for IGFBP-3 was 1.03 in the treatment group and 1.54 in the placebo group (p = 0.005). The staining intensity of nuclear androgen receptors on benign and cancerous cells was not significantly different between the treatment and placebo groups. However, there was a significant difference in androgen receptor staining between benign and cancer cells in the 2 populations. Mean nuclear androgen receptor staining intensity in all cancer and all benign tissue samples was 119.3 and 151.8, respectively (0.001). Finasteride administered 30 days before surgery appears to decrease the apoptotic factors caspase-7 and IGFBP-3 in cancer cells, while having little to no effect on caspase-3, insulin growth factor-1, bcl-2, p53 and p21. This short-term study may have interesting implications for interpreting Prostate Cancer Prevention Trial data on the molecular level. No differences were noted between the treatment and placebo groups in the expression of nuclear androgen receptor. However, decreased expression of androgen receptors was present in cancer cells compared to that in benign prostate cells in the 2 groups.

Insulin receptor expression by human prostate cancers

Although recent laboratory and population studies suggest that prostate cancer may be responsive to insulin, there is a gap in knowledge concerning the expression of insulin receptors on benign or malignant prostate tissue. We immunostained 644 cores on tissue microarrays prepared from 29 prostate tissue samples without malignancies, 78 Gleason grade 3 cancers, 21 Gleason grade 4 cancers and 33 Gleason grade 5 cancers with antibodies against the insulin-like growth factor I receptor and the insulin receptor. We observed immunoreactivity with both antibodies, which implies the presence of hybrid receptors as well as IGF-I receptors and insulin receptors. Insulin receptor staining intensity was significantly (P < 0.001) higher on malignant than benign prostate epithelial cells. Analysis of information from public gene expression databases confirmed that co-expression of insulin receptor mRNA and IGF-I receptor mRNA is common in prostate cancer specimens. RT-PCR methods provided evidence for the presence of mRNA for both IR-A and IR-B insulin receptor isoforms. These observations document the presence of insulin receptors on primary human prostate cancers. The findings are relevant not only to ongoing clinical trials of drug candidates that target IGF-I and/or insulin receptors, but also to the hypothesis that obesity-associated hyperinsulinemia mediates the adverse effect of obesity on prostate cancer prognosis.

Adrenergic Receptors in the Ptotic Human Eyelid: Correlation With Phenylephrine Testing and Surgical Success in Ptosis Repair

To investigate the relationship between adrenergic receptors in Müller muscle and response to phenylephrine testing in patients undergoing ptosis surgery. This study also compares outcomes of Fasanella and Putterman approaches to posterior ptosis repair. Prospective analysis of 71 patients undergoing posterior ptosis surgery. Eyelid height was measured before and after phenylephrine. Müller muscle was examined for alpha-1D, alpha-2C, beta-1, and beta-2 receptors. Specimens were graded on receptor staining intensity. Patients were seen 1 week and 6 weeks following surgery. Surgical outcomes were scored on a scale of 1 (most favorable) to 3 (least favorable). Adrenergic receptors were found in decreasing order: alpha-1D, beta-1, alpha-2C, and beta-2. Receptor grade significantly predicted eyelid height for alpha-2C receptors (p = .03). Mean outcome scores for 36 Putterman (1.10) and 35 Fasanella (1.27) procedures were not significantly different. Alpha 1D, alpha-2C, and beta-2 receptors are documented within human Müller muscle. Human eyelid elevation response to phenylephrine is inversely related to the amount of alpha-2C receptor staining in Müller muscle. Fasanella and Putterman procedures have equal outcomes, independent of adrenergic receptors.

Semi‐automated imaging system to quantitate estrogen and progesterone receptor immunoreactivity in human breast cancer

A semi-automated imaging system is described to quantitate estrogen and progesterone receptor immunoreactivity in human breast cancer. The system works for any conventional method of image acquisition using microscopic slides that have been processed for immunohistochemical analysis of the estrogen receptor and progesterone receptor. Estrogen receptor and progesterone receptor immunohistochemical staining produce colorimetric differences in nuclear staining that conventionally have been interpreted manually by pathologists and expressed as percentage of positive tumoral nuclei. The estrogen receptor and progesterone receptor status of human breast cancer represent important prognostic and predictive markers of human breast cancer that dictate therapeutic decisions but their subjective interpretation result in interobserver, intraobserver and fatigue variability. Subjective measurements are traditionally limited to a determination of percentage of tumoral nuclei that show positive immunoreactivity. To address these limitations, imaging algorithms utilizing both colorimetric (RGB) as well as intensity (gray scale) determinations were used to analyze pixels of the acquired image. Image acquisition utilized either scanner or microscope with attached digital or analogue camera capable of producing images with a resolution of 20 pixels /10 mu. Areas of each image were screened and the area of interest richest in tumour cells manually selected for image processing. Images were processed initially by JPG conversion of SVS scanned virtual slides or direct JPG photomicrograph capture. Following image acquisition, images were screened for quality, enhanced and processed. The algorithm-based values for estrogen receptor and progesterone receptor percentage nuclear positivity both strongly correlated with the subjective measurements (intraclass correlation: 0.77; 95% confidence interval: 0.59, 0.95) yet exhibited no interobserver, intraobserver or fatigue variability. In addition the algorithms provided measurements of nuclear estrogen receptor and progesterone receptor staining intensity (mean, mode and median staining intensity of positive staining nuclei), parameters that subjective review could not assess. Other semi-automated image analysis systems have been used to measure estrogen receptor and progesterone receptor immunoreactivity but these either have required proprietary hardware or have been based on luminosity differences alone. By contrast our algorithms were independent of proprietary hardware and were based on not just luminosity and colour but also many other imaging features including epithelial pattern recognition and nuclear morphology. These features provide a more accurate, versatile and robust imaging analysis platform that can be fully automated in the near future. Because of all these properties, our semi-automated imaging system 'adds value' as a means of measuring these important nuclear biomarkers of human breast cancer.

Altered distribution of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor subunit GluR2(4) and the N-methyl-D-aspartate receptor subunit NMDAR1 in the hippocampus of patients with temporal lobe epilepsy.

In patients with therapy-refractory temporal lobe epilepsy (TLE), alterations of glutamate receptors have been proposed as a mechanism for enhanced excitability. Using commercially available monoclonal antibodies specific for the N-methyl-D-aspartate (NMDA) receptor subunit NMDAR1 and for the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor subunit GluR2(4), we have examined the distribution of these polypeptides in human hippocampal tissue that was surgically removed from patients with intractable TLE. Surgical specimens were classified according to the presence of Ammon's horn sclerosis (AHS) or a focal lesion in the temporal lobe. Cell counts and a densitometric analysis of the immunoreactivity patterns were carried out for all hippocampal subfields. NMDAR1 and GluR2(4) levels were markedly reduced in patients with AHS, primarily in those subfields with substantial neuronal cell loss (in particular CA1, CA4 and CA3), compared to those seen in patients with focal lesions and in control specimens obtained at autopsy. In contrast, the molecular layer of the dentate gyrus (DG-ML) showed significantly higher levels of GluR2(4) immunoreactivity in AHS compared to control tissue, while NMDAR1 showed no significant up-regulation in this sublayer. When the receptor staining intensity was normalized for alterations in neuronal density, no significant alterations could be detected except for an increase in GluR2(4) in the DG-ML of patients with AHS. These changes may reflect synaptic reorganization observed in the DG-ML of specimens from patients with chronic intractable TLE.

In vivo observations of pre- and postsynaptic changes during the transition from multiple to single innervation at developing neuromuscular junctions

Synaptic rearrangements in developing muscle were studied by visualizing individual neuromuscular junctions in the sternomastoid muscle of living neonatal mice as they underwent the transition from multiple to single innervation. Vital staining of ACh receptors (AChRs) with rhodamine-conjugated alpha-bungarotoxin showed that while junctions were still multiply innervated (usually by two motor axons), regions of the postsynaptic membrane within each junction became depleted of receptors. Usually, several small postsynaptic areas lost AChRs in succession. In these areas, AChRs already in the membrane rapidly disappeared compared to a low level of receptor turnover elsewhere in the junction. Moreover, there was no evidence of new AChRs being inserted into these areas. Within each postsynaptic area undergoing AChR depletion, the intensity of receptor staining decreased gradually over 1-2 d. In some junctions, it appeared that AChRs were migrating away from areas being depleted of receptors. The depletion of AChRs from some sites in combination with the spreading apart of the entire receptor-rich area due to muscle fiber growth accounts for the transformation from plaque-like to branched receptor distributions at developing neuromuscular junctions. Vital staining of presynaptic motor nerve terminals at junctions whose postsynaptic AChRs were also stained showed that motor nerve terminals were lost from the same areas that were depleted of receptors postsynaptically. Postsynaptic areas began to be depleted of AChRs before there was any obvious loss of membrane or intracellular staining in the overlying nerve terminal. Only when a single innervating axon remained at a junction did loss of motor nerve terminals and underlying AChRs largely cease. That former synaptic areas could at later times be identified as uninnervated regions within a junction indicates that synapse elimination during development leaves an indelible mark on synaptic structure. These observations suggest that the withdrawal of a motor axon from a neuromuscular junction occurs as a consequence of the stepwise elimination of all of its synapses with that muscle fiber. These results also suggest that an important aspect of synaptic competition leading to axon withdrawal is the precocious loss of AChRs beneath the nerve terminals of the axon that will be eliminated. A similar early loss of AChRs beneath one axon's synapses has been shown to occur during synapse elimination in reinnervated adult muscle (Rich and Lichtman, 1989a).(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of pubertal development on estrogen receptor levels and stromal morphology in the guinea pig prostate.

Using an immunocytochemical assay (ERICA) with a monoclonal antibody (H222Sp gamma) to the human estrogen receptor, we have demonstrated a stromal localization of the estrogen receptor in the dorsolateral prostate of the guinea pig. Specific staining of estrogen receptor in the guinea pig prostate was confined to the nuclei of periacinar and interacinar stromal cells. In comparison with prepubertal tissues, estrogen receptor staining intensity was markedly reduced in postpubertal prostatic tissues. No immunoreactive estrogen receptor was detected in the acinar epithelial cells irrespective of the developmental stage of the guinea pig prostate. Electron microscopic examination of the guinea pig prostate showed that the stromal component consists predominantly of smooth muscle cells, which, during pubertal development, undergo marked cytological changes and increase in size. These changes in the prostatic stroma were associated with a greater than fivefold reduction in levels of cytosolic and nuclear estrogen receptor determined by either a radioligand binding assay or an enzyme immunoassay (EREIA) and expressed relative to soluble protein. Morphometric analysis of the prostatic stromal cell density (SCD: nuclei/mm2 interacinar stroma), which is inversely proportional to stromal cell size, indicated that the SCD decreased approximately threefold during pubertal development. Furthermore, cytosolic estrogen receptor levels in mechanically separated prostatic stromal fractions were found to vary concordantly with the SCD during pubertal development. To determine whether estrogen influences normal development of the guinea pig prostate, the effect of various hormonal manipulations on stromal development was examined. Castration of prepubertal animals prevented the threefold decrease in SCD that is characteristic of pubertal development. Treatment of prepubertal castrates with estradiol and 5 alpha-dihydrotestosterone (DHT) in combination over a period equivalent to the transpubertal growth phase resulted in a stromal cell density similar to that seen in prostatic sections from intact postpubertal animals. In contrast, treatment of prepubertal castrates with either estradiol or DHT alone resulted in a prostatic stromal cell density intermediate between that observed in intact prepubertal and postpubertal animals. These findings suggest that both estrogen and androgen are required for the normal development of the guinea pig prostatic stroma.