Alternations of ER, PR, HER-2/neu, and P53 protein expression in ductal breast carcinomas and clinical implications

Mutations in transmembrane proteins: diseases, evolutionary insights, prediction and comparison with globular proteins

Membrane proteins are unique in that they interact with lipid bilayers, making them indispensable for transporting molecules and relaying signals between and across cells. Due to the significance of the protein's functions, mutations often have profound effects on the fitness of the host. This is apparent both from experimental studies, which implicated numerous missense variants in diseases, as well as from evolutionary signals that allow elucidating the physicochemical constraints that intermembrane and aqueous environments bring. In this review, we report on the current state of knowledge acquired on missense variants (referred to as to single amino acid variants) affecting membrane proteins as well as the insights that can be extrapolated from data already available. This includes an overview of the annotations for membrane protein variants that have been collated within databases dedicated to the topic, bioinformatics approaches that leverage evolutionary information in order to shed light on previously uncharacterized membrane protein structures or interaction interfaces, tools for predicting the effects of mutations tailored specifically towards the characteristics of membrane proteins as well as two clinically relevant case studies explaining the implications of mutated membrane proteins in cancer and cardiomyopathy.

The effect of immunohistochemically detected p53 accumulation in prognosis of breast cancer; A retrospective survey of outcome

BACKGROUND

P53; a tumor suppressor gene has known to have a role in a group of human cancers. Its role in breast cancer; one of the most prevalent malignancies worldwide, is still controversial. The current study is designed to evaluate the prognostic role of p53 mutation in breast cancer.

METHODS

one hundred and eighty five breast cancer patients were studied in this retrospective study. P53 mutation was detected by accumulation of p53 protein in the patients' pathology samples. Immunohistochemistry (IHC) was used to detect the protein. The effect of p53 on the final outcome was assessed using Kaplan-Meier estimate of survival and compared by log-rank test. Prognostic effects analyzed by cox proportional hazard models.

RESULTS

while the stage of the disease at presentation was not significantly different between p53 positive and negative patients, those with p53 mutation had a significantly poorer outcome in terms of overall and disease-free survival rates (OS and DFS). In a multivariate analysis hazard ratio of p53 mutation was about 5 and 3.8 for OS and DFS respectively. They also had a higher cumulative incidence of relapse.

CONCLUSION

It seems that p53 mutation is an independent prognostic factor for breast cancer. Although larger prospective studies are needed to clarify the importance of such a conclusion.

Breast-specific gamma imaging with Tc-99m-sestamibi in the diagnosis of breast cancer and its semiquantitative index correlation with tumor biologic markers, subtypes, and clinicopathologic characteristics

OBJECTIVES

To determine the sensitivity of breast-specific gamma imaging (BSGI) in diagnosing breast cancer and assess the potential correlation between the semiquantitative index of BSGI and biologic markers, molecular subtypes, and clinicopathologic characteristics of breast cancer.

MATERIALS AND METHODS

The sensitivity of BSGI for breast cancer was retrospectively assessed in 102 female breast cancer patients who underwent BSGI before surgery and was compared with that of ultrasonography and mammography. BSGI was visually graded on the basis of the Society of Nuclear Medicine and Molecular Imaging guideline. Tracer uptake in the cancer as the lesion to nonlesion ratio (L/N) was calculated semiquantitatively and was subsequently correlated to tumor biologic markers, molecular subtypes, and clinicopathologic characteristics.

RESULTS

The sensitivity of BSGI for breast cancer by visual analysis was 94.1% (96/102) in our cohort, which was 100% (47/47) in the subgroup of patients with a tumor size more than 2.0 cm and 89.1% (49/55) in the subgroup of patients with a size less than or equal to 2.0 cm. The sensitivity of BSGI was significantly higher than that of ultrasonography of 84.2% (85/101) (P=0.022) and mammography of 84.5% (60/71) (P=0.037). There was no significant correlation between the L/N and expressions of estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, and antigen Ki-67, and the subtypes or histologic grade of the cancer (P>0.05). However, the value of L/N was associated with infiltration degree (P=0.005), axillary lymph node status (P=0.029), and tumor size (P=0.002). Multivariate analysis further indicated that the value of L/N was correlated with infiltration degree (P=0.016) and tumor size (P=0.002).

CONCLUSION

BSGI has a high sensitivity for detecting primary breast cancer. The value of L/N on BSGI was independently related to infiltration degree and tumor size of breast cancer, but not to expression of tumor receptor markers and histologic grade.

Prognostic role of sex steroid receptors in pancreatic adenocarcinoma

From the available literature, it is unclear what proportion of pancreatic adenocarcinomas express estrogen receptors (ERα, ERβ), progesterone receptors (PR), and androgen receptors (AR), and if any of these markers have prognostic significance. We aimed to assess (1) the expression and (2) the correlation of the aforementioned markers with clinicopathological parameters and prognosis in patients with pancreatic adenocarcinoma. During a five-year period, 60 patients with pancreatic ductal adenocarcinoma underwent surgical resection at a single institution. Immunohistochemical stains of the studied markers were quantified by Image analysis system. ERα expression was positively associated with PR expression. Moreover, ERβ was inversely associated with the presence of metastases, whereas no significant associations implicated AR. As far as the prognostic significance of the studied receptors is concerned, higher ERα expression correlated with poorer survival at the univariate analysis, but the finding dissipated at the multivariate approach. No significant associations with overall survival were noted regarding the other receptors. The role of sex hormone receptors in the survival from pancreatic adenocarcinoma seems rather limited. Further prospective studies assessing those receptors should ideally be designed in order to confirm our results and possibly outline additional correlations between other steroid receptors and features of pancreatic adenocarcinoma.

Clinicopathological variables predicting HER-2 gene status in immunohistochemistry-equivocal (2+) invasive breast cancer

BACKGROUND AND OBJECTIVE

Human epidermal growth factor receptor-2 (HER-2) gene status is crucial to guide treatment decisions regarding the use of HER-2-targeted therapies in breast cancer. An invasive breast cancer with HER-2 2+ score is regarded as HER-2 status equivocal and should further determine by fluorescent in situ hybridization (FISH), which is considered the standard test for HER-2 status. Here, we aimed to establish a risk score to allow for prediction of the presence of HER-2 gene status.

METHODS

A total of 182 HER-2 2+ by immunohistochemistry (IHC) invasive breast cancer cases were enrolled in this study. The association between clinicopathological variables like age, sex, tumor grade, hormone receptor (HR) status, P53 and proliferation index (Ki67), and FISH result using US Food and Drug Administration (FDA) criteria was evaluated. Also, we compared the HER-2 FISH results using FDA criteria and 2013 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guideline.

RESULTS

The study population had a median age of 48 years (range, 29-78 years). Estrogen receptor (ER) was expressed in 131 (72.0%) patients. 73.1% of patients (133/182) were progesterone receptor (PR) positive. The median Ki67 value was 20% (range, 3-90%). There was good agreement between the FDA and 2013 ASCO/CAP guideline. Sixty-three of all patients were HER-2 FISH amplified (positive) based on FDA criteria. Tumors with HER-2 amplified were more likely to harbor ER negative (58.8% vs. 25.2%, P<0.001) or PR negative (57.1% vs. 26.3%, P<0.001) or P53 negative (44.8% vs. 29.8%, P=0.048). A significant high level of Ki67 was detected in HER-2 amplified groups (P=0.006). We created a risk score that comprised HR, P53 and Ki67. A significant association between risk score and HER-2 FISH amplification was observed (χ(2)=30.41, P<0.001).

CONCLUSIONS

This novel immunohistochemical risk score could be highly useful to predict the presence of HER-2 gene status in invasive breast cancer.

Joint detection of multiple immunohistochemical indices and clinical significance in breast cancer

Breast cancer is one of the most common malignancies in women. This study was conducted to analyze the association between the expressions of eight immunohistochemical (IHC) indices and clinicopathological characteristics in breast cancers (BCs) and investigate the clinical significance. IHC Envision ldpe-g-nvp was used to detect the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2), vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), p53, type II topoisomerase (TOPO II) and Ki-67 in postoperative paraffin blocks of 286 cases of invasive BC and statistically analyzed their correlations with clinicopathological characteristics. The positive rates of ER, PR, HER2, VEGF, p53, EGFR, TOPO II and Ki-67 expression were 62.24, 41.96, 57.34, 53.85, 81.82, 46.85, 54.55 and 69.93%, respectively. ER expression was negatively correlated with age, tumor size and histological grade (P<0.05) and PR expression was negatively correlated with age and histological grade (P<0.05). Among the ER, PR and c-erbB-2 statuses, a significant correlation was observed between ER expression and PR status (P=0.0000), whereas the expression of ER and PR exhibited a negative correlation with HER2 status (P<0.05). We also demonstrated a significant correlation between EGFR expression and lymph node metastasis (P=0.0240), p53 expression and tumor size (P=0.0300), p53 and Ki-67 expression and histological grade (P<0.05) and the expressions of VEGF, EGFR, p53, TOPO II, Ki-67 and HER2 status (P<0.05). In addition, the Luminal B and HER2/neu subtypes exhibited a close correlation with age (P<0.01), while the HER2/neu and triple-negative subtypes were positively correlated with poor histological grade (P<0.05). In conclusion, there is a definite correlation between IHC indices and clinicopathological characteristics in BCs. Combined detection of these indices may be significant in the evaluation of biological behavior and prognosis of BC and thus in the diagnosis and comprehensive treatment of this disease.

Establishment of a mammary carcinoma cell line from Syrian hamsters treated with N-methyl-N-nitrosourea

Clearly new breast cancer models are necessary in developing novel therapies. To address this challenge, we examined mammary tumor formation in the Syrian hamster using the chemical carcinogen N-methyl-N-nitrosourea (MNU). A single 50mg/kg intraperitoneal dose of MNU resulted in a 60% incidence of premalignant mammary lesions, and a 20% incidence of mammary adenocarcinomas. Two cell lines, HMAM4A and HMAM4B, were derived from one of the primary mammary tumors induced by MNU. The morphology of the primary tumor was similar to a high-grade poorly differentiated adenocarcinoma in human breast cancer. The primary tumor stained positively for both HER-2/neu and pancytokeratin, and negatively for both cytokeratin 5/6 and p63. When the HMAM4B cell line was implanted subcutaneously into syngeneic female hamsters, tumors grew at a take rate of 50%. A tumor derived from HMAM4B cells implanted into a syngeneic hamster was further propagated in vitro as a stable cell line HMAM5. The HMAM5 cells grew in female syngeneic hamsters with a 70% take rate of tumor formation. These cells proliferate in vitro, form colonies in soft agar, and are aneuploid with a modal chromosomal number of 74 (the normal chromosome number for Syrian hamster is 44). To determine responsiveness to the estrogen receptor (ER), a cell proliferation assay was examined using increasing concentrations of tamoxifen. Both HMAM5 and human MCF-7 (ER positive) cells showed a similar decrease at 24h. However, MDA-MB-231 (ER negative) cells were relatively insensitive to any decrease in proliferation from tamoxifen treatment. These results suggest that the HMAM5 cell line was likely derived from a luminal B subtype of mammary tumor. These results also represent characterization of the first mammary tumor cell line available from the Syrian hamster. The HMAM5 cell line is likely to be useful as an immunocompetent model for human breast cancer in developing novel therapies.