AKR1B1 and AKR1B10 as Prognostic Biomarkers of Endometrioid Endometrial Carcinomas.

The roles of aldo-keto reductase family 1 member B1 (AKR1B1) and B10 (AKR1B10) in the pathogenesis of many cancers have been widely reported but only briefly studied in endometrial cancer. To clarify the potential of AKR1B1 and AKR1B10 as tissue biomarkers of endometrial cancer, we evaluated the immunohistochemical levels of AKR1B1 and AKR1B10 in tissue paraffin sections from 101 well-characterized patients with endometrioid endometrial cancer and 12 patients with serous endometrial cancer and compared them with the clinicopathological data. Significantly higher immunohistochemical levels of AKR1B1 and AKR1B10 were found in adjacent non-neoplastic endometrial tissue compared to endometrioid endometrial cancer. A trend for better survival was observed in patients with higher immunohistochemical AKR1B1 and AKR1B10 levels. However, no statistically significant differences in overall survival or disease-free survival were observed when AKR1B1 or AKR1B10 were examined individually in endometrioid endometrial cancer. However, analysis of AKR1B1 and AKR1B10 together revealed significantly better overall and disease-free survival in patients with both AKR1B1 and AKR1B10 staining above the median values compared to all other patients. Multivariant Cox analysis identified strong AKR1B1 and AKR1B10 staining as a statistically important survival prediction factor. Conversely, no significant differences were found in serous endometrial cancer. Our results suggest that AKR1B1 and AKR1B10 play protective roles in endometrioid endometrial cancer and show potential as prognostic biomarkers.

Altered Profile of E1-S Transporters in Endometrial Cancer: Lower Protein Levels of ABCG2 and OSTß and Up-Regulation of SLCO1B3 Expression.

Endometrial cancer (EC) is associated with increased estrogen actions. Locally, estrogens can be formed from estrone-sulphate (E1-S) after cellular uptake by organic anion-transporting polypeptides (OATP) or organic anion transporters (OAT). Efflux of E1-S is enabled by ATP Binding Cassette transporters (ABC) and organic solute transporter (OST)αß. Currently, 19 E1-S transporters are known but their roles in EC are not yet understood. Here, we analysed levels of E1-S transporters in Ishikawa (premenopausal EC), HEC-1-A (postmenopausal EC), HIEEC (control) cell lines, in EC tissue, examined metabolism of steroid precursor E1-S, studied effects of OATPs' inhibition and gene-silencing on E1-S uptake, and assessed associations between transporters and histopathological data. Results revealed enhanced E1-S metabolism in HEC-1-A versus Ishikawa which could be explained by higher levels of OATPs in HEC-1-A versus Ishikawa, especially 6.3-fold up-regulation of OATP1B3 (SLCO1B3), as also confirmed by immunocytochemical staining and gene silencing studies, lower ABCG2 expression and higher levels of sulfatase (STS). In EC versus adjacent control tissue the highest differences were seen for ABCG2 and SLC51B (OSTß) which were 3.0-fold and 2.1-fold down-regulated, respectively. Immunohistochemistry confirmed lower levels of these two transporters in EC versus adjacent control tissue. Further analysis of histopathological data indicated that SLCO1B3 might be important for uptake of E1-S in tumours without lymphovascular invasion where it was 15.6-fold up-regulated as compared to adjacent control tissue. Our results clearly indicate the importance of E1-S transporters in EC pathophysiology and provide a base for further studies towards development of targeted treatment.

AKR1C3 Is Associated with Better Survival of Patients with Endometrial Carcinomas.

The aldo-keto reductase (AKR) superfamily is gaining attention in cancer research. AKRs are involved in important biochemical processes and have crucial roles in carcinogenesis and chemoresistance. The enzyme AKR1C3 has many functions, which include production of prostaglandins, androgens and estrogens, and metabolism of different chemotherapeutics; AKR1C3 is thus implicated in the pathophysiology of different cancers. Endometrial and ovarian cancers represent the majority of gynecological malignancies in developed countries. Personalized treatments for these cancers depend on identification of prognostic and predictive biomarkers that allow stratification of patients. In this study, we evaluated the immunohistochemical (IHC) staining of AKR1C3 in 123 paraffin-embedded samples of endometrial cancer and 99 samples of ovarian cancer, and examined possible correlations between expression of AKR1C3 and other clinicopathological data. The IHC expression of AKR1C3 was higher in endometrial cancer compared to ovarian cancer. In endometrioid endometrial carcinoma, high AKR1C3 IHC expression correlated with better overall survival (hazard ratio, 0.19; 95% confidence interval, 0.06-0.65, p = 0.008) and with disease-free survival (hazard ratio, 0.328; 95% confidence interval, 0.12-0.88, p = 0.027). In patients with ovarian cancer, there was no correlation between AKR1C3 IHC expression and overall and disease-free survival or response to chemotherapy. These results demonstrate that AKR1C3 is a potential prognostic biomarker for endometrioid endometrial cancer.

Membrane progesterone receptors ß and γ have potential as prognostic biomarkers of endometrial cancer.

Endometrial cancer (EC) is one of the most common malignancies in women worldwide. EC is linked to chronic exposure to estrogens that is unopposed by protective effects of progesterone. Progesterone modulates gene expression via classical nuclear receptors, and has rapid effects via the less characterized membrane-bound progesterone receptors (mPRs) of the progestin and adipoQ receptor (PAQR) family. The presence of mPRs in EC has not been investigated to date. The aims of this study were to examine PAQR7, PAQR8 and PAQR5, which encode for mPRα, mPRß and mPRγ, respectively, for their expression and localization in EC tissue and adjacent control endometrium. Our results reveal decreased expression of PAQR7 and PAQR8, and unaltered expression of PAQR5 in EC versus control tissue. Expression of PAQR5 was decreased in EC with higher FIGO stage versus stage IA. Immunohistochemistry revealed lower levels of mPRα and mPRß, but higher levels of mPRγ, in EC versus control tissue. There was greater decrease in mPRß levels in tumors with lymphovascular invasion. The analysis of the expression data associates higher PAQR5 mRNA and mPRß protein levels with favorable patient prognosis. Immunohistochemistry showed diverse localizations of mPRs in control and cancer endometrium. In control endometrium, mPRα and mPRß were localized mostly at the cell membranes, while mPRγ was localized in the cytoplasm and/or nucleus. In cancer endometrium, mPRα and mPRß were detected at the cell membrane or in the cytoplasm, or both, while mPRγ was only localized in the cytoplasm. Taken together, these results imply that mPRs are involved in EC pathogenesis through effects on the development or progression of cancer. The potential role of mPRß and mPRγ as prognostic biomarkers needs to be further assessed on a larger number of samples.

Detection of Aristaless-related homeobox protein in ovarian sex cord-stromal tumors.

OBJECTIVE: To examine the potential of ARX as a novel biomarker of ovarian endometriosis and other ovarian pathologies. METHODS: The mRNA level of ARX in ovarian endometriosis and normal endometrium samples was determined by real-time PCR, while the protein level was determined by Western blotting and immunohistochemical staining. Immunohistochemical analysis was performed on nearly 200 tissue samples of different ovarian pathologies. GraphPad Prism was used for statistical analysis. RESULTS: The expression of ARX was significantly increased in ovarian endometriosis samples as compared to normal endometrium. Also Western blotting data showed higher ARX levels in the ovarian endometriosis samples versus normal endometrium. Immunohistochemical analysis revealed that the protein is localized in the ovarian stroma and does not originate from endometriosis. Further immunohistochemical analysis performed on several different non-neoplastic and neoplastic ovarian tissue samples revealed that in the non-neoplastic ovary ARX protein is present only in the stromal cells and their derivates (luteinized stromal cells, theca and Leydig cells) and not in granulosa cells, oocites, surface epithelium or rete ovarii, while all stromal and sex cord tumors showed strong nuclear staining for ARX. All other primary or metastatic epithelial tumors of the ovary were ARX negative. CONCLUSIONS: ARX is not associated with endometriosis and cannot be used as a biomarker for ovarian endometriosis. ARX is present in ovarian stroma and cells derived from ovarian stroma as well as in all types of sex cord-stromal tumors of the ovary and could thus be used as a marker for sex cord-stromal differentiation in ovarian tumors.

Cancer Stem Cell-Related Marker NANOG Expression in Ovarian Serous Tumors: A Clinicopathological Study of 159 Cases.

OBJECTIVE: The objectives of this study were to assess cancer stem cell-related marker NANOG expression in ovarian serous tumors and to evaluate its prognostic significance in relation to ovarian serous carcinoma. METHODS: NANOG protein expression was immunohistochemically evaluated in the ovarian tissue microarrays of 20 patients with benign ovarian serous tumors, 30 patients with borderline ovarian serous tumors, and 109 patients with ovarian serous carcinomas, from which 106 were of high-grade and 3 of low-grade morphology Immunohistochemical reaction was scored according to signal intensity and the percentage of positive cells in tumor samples. Pursuant to our summation of signal intensity and positive cell occurrence, we divided our samples into 4 groups: NANOG-negative, NANOG-slightly positive, NANOG-moderately positive, and NANOG-strongly positive group. Complete clinical data were obtained for the ovarian serous carcinoma group, and correlation between clinical data and NANOG expression was analyzed. RESULTS: A specific brown nuclear, or cytoplasmic reaction, was considered a positive NANOG staining. In terms of the ovarian serous carcinoma group, 69.7% were NANOG positive, 22.9% slightly positive, 22.9% moderately positive, and 23.9% strongly positive. All NANOG-positive cases were of high-grade morphology. Benign and borderline tumors and low-grade serous carcinomas were NANOG negative. There was no significant correlation between NANOG expression and clinical parameters in terms of the ovarian serous carcinoma group. CONCLUSIONS: Positive NANOG expression is significantly associated with high-grade ovarian serous carcinoma and is absent in benign, borderline, and low-grade serous lesions. In our study, there was no correlation between NANOG expression and clinical parameters, including its use in the prognosis of ovarian serous carcinoma.

Novel algorithm including CA-125, HE4 and body mass index in the diagnosis of endometrial cancer.

OBJECTIVES: To evaluate the diagnostic and prognostic potential of preoperative serum CA-125 and HE4 levels in patients with endometrial cancer. METHODS: Prospective case-control study of 133 women who underwent surgical treatment at the University Medical Centre Ljubljana (64 patients with endometrial cancer, 69 control patients with prolapsed uterus or myoma). Serum CA-125 and HE4 levels were determined using electrochemiluminescent assays. RESULTS: Serum CA-125 and HE4 levels were significantly higher in patients with endometrial cancer, compared to the controls (p=2.67×10-4, 1.36×10-7, respectively). A diagnostic model that combines serum CA-125 and HE4 levels and body mass index separated patients with endometrial cancer from controls, with AUC of 0.804, sensitivity of 66.7%, and specificity of 84.6%. Serum HE4 levels showed good prognostic potential and stratified the patients according to presence/absence of deep myometrial invasion (p=0.001) or lymphovascular invasion (p=0.003), with AUCs of 0.78 and 0.81, respectively. In low-risk patients with grade 1 and 2 endometrioid cancer for whom lymphadenectomy can be avoided, HE4 allowed stratification according to deep myometrial invasion (p=3.39×10-4), with AUC of 0.84. Although median HE4 levels were higher in patients with lymphovascular invasion, this difference did not reach significance (p=0.06). CONCLUSIONS: A model based on preoperative serum CA-125 and HE4 levels and body mass index has good diagnostic accuracy for separation of patients with endometrial cancer and control patients. In patients with endometrial cancer, serum HE4 levels allow prediction of deep myometrial and lymphovascular invasion.

The Significance of the Sulfatase Pathway for Local Estrogen Formation in Endometrial Cancer.

Endometrial cancer (EC) is the most common estrogen-dependent gynecological malignancy in the developed World. To investigate the local formation of estradiol (E2), we first measured the concentrations of the steroid precursor androstenedione (A-dione) and the most potent estrogen, E2, and we evaluated the metabolism of A-dione, estrone-sulfate (E1-S), and estrone (E1) in cancerous and adjacent control endometrium. Furthermore, we studied expression of the key genes for estradiol formation via the aromatase and sulfatase pathways. A-dione and E2 were detected in cancerous and adjacent control endometrium. In cancerous endometrium, A-dione was metabolized to testosterone, and no E2 was formed. Both, E1-S and E1 were metabolized to E2, with increased levels of E2 seen in cancerous tissue. There was no significant difference in expression of the key genes of the aromatase (CYP19A1) and the sulfatase (STS, HSD17B1, HSD17B2) pathways in cancerous endometrium compared to adjacent control tissue. The mRNA levels of CYP19A1 and HSD17B1 were low, and HSD17B14, which promotes inactivation of E2, was significantly down-regulated in cancerous endometrium, especially in patients with lymphovascular invasion. At the protein level, there were no differences in the levels of STS and HSD17B2 between cancerous and adjacent control tissue by Western blotting, and immunohistochemistry revealed intense staining for STS and HSD17B2, and weak staining for SULT1E1 and HSD17B1 in cancerous tissue. Our data demonstrate that in cancerous endometrium, E2 is formed from E1-S via the sulfatase pathway, and not from A-dione via the aromatase pathway.

Data on expression of genes involved in estrogen and progesterone action, inflammation and differentiation according to demographic, histopathological and clinical characteristics of endometrial cancer patients.

Endometrial cancer is the sixth most common cancer in women worldwide. It is associated with aberrant actions of steroid hormones, estrogens and progesterone, but also with enhanced inflammation and reduced cellular differentiation. Here, we show data on demographic and histopathological characteristics of 51 patients with endometrial cancer, together with data on correlations between the expression of 38 genes involved in estrogen and progesterone actions, inflammation and differentiation, and demographic characteristics. We also show data on changes in gene expression of these 38 genes according to histopathological and clinical characteristics of these patients. This article includes data referenced in the manuscript entitled ¼STAR and AKR1B10 are down-regulated in high-grade endometrial cancer by Sinreih et al. (in press) [1].

STAR and AKR1B10 are down-regulated in high-grade endometrial cancer.

Endometrial cancer is the most frequent gynecological malignancy in the developed world. The majority of cases are estrogen dependent, and are associated with diminished protective effects of progesterone. Endometrial cancer is also related to enhanced inflammation and decreased differentiation. In our previous studies, we examined the expression of genes involved in estrogen and progesterone actions in inflammation and tumor differentiation, in tissue samples from endometrial cancer and adjacent control endometrium. The aims of the current study were to examine correlations between gene expression and several demographic characteristics, and to evaluate changes in gene expression with regard to histopathological and clinical characteristics of 51 patients. We studied correlations and differences in expression of 38 genes involved in five pathophysiological processes: (i) estrogen-stimulated proliferation; (ii) estrogen-dependent carcinogenesis; (iii) diminished biosynthesis of progesterone: (iv) enhanced formation of progesterone metabolites; and (v) increased inflammation and decreased differentiation. Spearman correlation coefficient analysis shows that expression of PAQR7 correlates with age, expression of SRD5A1, AKR1B1 and AKR1B10 correlate with body mass, while expression of SRD5A1 and AKR1B10 correlate with body mass index. When patients with endometrial cancer were stratified based on menopausal status, histological grade, myometrial invasion, lymphovascular invasion, and FIGO stage, Mann-Whitney U tests revealed significantly decreased expression of STAR (4.4-fold; adjusted p=0.009) and AKR1B10 (9-fold; adjusted p=0.003) in high grade versus low grade tumors. Lower levels of STAR might lead to decreased de-novo steroid hormone synthesis and tumor differentiation, and lower levels of AKR1B10 to diminished elimination of toxic electrophilic carbonyl compounds in high-grade endometrial cancer. These data thus reveal the potential of STAR and AKR1B10 as prognostic biomarkers, which calls for further validation at the protein level.

Results of the FIT-based National Colorectal Cancer Screening Program in Slovenia.

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies in the western world. OBJECTIVE: We aimed to assess the first round of fecal immunochemical test (FIT)-based National CRC screening program (NCSP). METHODS: In the NCSP conducted in Slovenia, a FIT and colonoscopy for those tested positive was used. The NCSP central unit sent 536,709 invitations to Slovenian residents age 50 to 69 years old between 2009 and 2011. The adherence rate was 56.9% (303,343 participants). FIT was positive in 6.2% (15,310) of the participants (men, 7.8%; women, 5.0%; P<0.01). A total of 13,919 unsedated colonoscopies were performed with the cecal intubation rate of 97.8%. RESULTS: The overall adenoma detection rate was 51.3% [95% confidence interval (CI), 50.5%-52.1%] of which 61.0% (95% CI, 59.9%-62.1%) was in men, and 39.1% (95% CI, 37.8%-40.3%) in women (P<0.01). The mean number of adenoma per positive colonoscopy was 1.94 (95% CI, 1.90-1.97). Adenoma, advanced adenoma, or cancer were found in 7732 (55.5%) colonoscopies. A total of 862 (6.2%) CRC cases were found. Only 161 (18.7%) carcinomas were situated in the right colon. A total of 597 (70.2%) patients with cancer were in the early clinical stages (N, negative; 194 22.8%) of all cancers were cured with only endoscopic resection. CONCLUSIONS: In the NCSP, CRC was found in 6.2% of those participants attending colonoscopy, with 81.3% of carcinomas found in the left colon. A localized clinical stage was found in 70.2% participants. In 22.8% of CRC patients, cancer was cured with endoscopic resection only.

Angiogenesis in triple-negative adenoid cystic carcinomas of the breast.

We compared microvascular density (MVD), lymph vessel density (LVD), and the expression of hypoxia pathway-associated proteins between primary triple-negative adenoid cystic carcinoma of the breast (TN-ACC) and grade-matched triple-negative breast carcinomas of no special type (TNBC). Twelve TN-ACC and 15 TNBC were investigated immunohistochemically for CD31, podoplanin (D2-40), von Hippel-Lindau protein (pVHL), and hypoxia-inducible factor-1alpha (HIF-1α) protein. All cases were lymph node negative (pN0). The study revealed a median MVD (CD31) of 34 vessels/mm(2) (mean ± SD, 41.33 ± 6.5/mm(2)) in the TN-ACC subgroup and a median of 55 microvessels (mean ± SD, 54.9 ± 6.3/mm(2)) in the TNBC subgroup. The median LVD (D2-40) was 10.5/mm(2) (mean ± SD, 11.9 ± 1.5/mm(2)) in the TN-ACC subgroup and 15.0/mm(2) (mean ± SD, 16.9 ± 2.5/mm(2)) lymph vessels in the TNBC subgroup. The differences were not statistically significant (P = 0.93, P = 0.67, respectively). pVHL was detectable in all TN-ACCs whereas two cases of TNBC had less than 5% of the positive cells. HIF-1α protein expression was significantly higher in the tumor cell population than in adjacent normal cells in both subgroups (P = 0.009 for TNBC and P = 0.028 for TN-ACC, respectively), but there was no significant difference between the two tumor groups. Up-regulation of the hypoxia-induced signaling is seen in both TN-ACC and grade-matched TNBC. Despite its perceived low malignant potential, TN-ACC of the breast does not differ in the number of blood and lymphatic vessels in comparison with the grade-matched TNBC. The reported biologic differences between TN-ACC and TNBC do not appear to result from neoangiogenesis.

Combined effect of CYP1B1, COMT, GSTP1, and MnSOD genotypes and risk of postmenopausal breast cancer.

OBJECTIVE: Estrogen plays a key role in breast cancer development and functionally relevant genetic variants within the estrogen metabolic pathway are prime candidates for a possible association with breast cancer risk. We investigated the independent and the combined effects of commonly occurring polymorphisms in four genes encoding key proteins of estrogen metabolic pathway on their potential contribution to breast cancer risk. METHODS: We studied 530 breast cancer cases and 270 controls of the same age and ethnicity participating in a case-control study of postmenopausal women. Genotyping was conducted for CYP1B1 (rs1056836), COMT (rs4680), GSTP1 (rs1695), and MnSOD (rs4880) polymorphisms by polymerase chain reaction based restriction fragment length polymorphism and TaqMan allelic discrimination method. Adjusted ORs and 95% CIs were calculated using logistic regression. RESULTS: None of the 4 genetic variants examined contributed to breast cancer risk individually. When the combined effects of the risk genotypes were investigated, significant associations were observed among women with two high-risk genotypes in CYP1B1 and COMT (OR, 2.0; 95% CI, 1.1 to 3.5) and two high-risk genotypes in COMT and MnSOD (OR, 2.0; 95% CI, 1.0 to 3.8), compared to those with low-risk genotypes. CONCLUSION: Our results suggest that individual susceptibility to breast cancer incidence may be increased by combined effects of the high-risk genotypes in CYP1B1, COMT, and MnSOD estrogen metabolic genes.

Breast tumor characteristics in hormone replacement therapy users.

The aim of this study was to further elucidate the influence of HRT use, regarding duration, regimen and route of administration, on breast tumor characteristics. We evaluated the associations between HRT use and breast tumor characteristics in 530 postmenopausal women diagnosed with invasive breast cancer. Detailed information on HRT use and mammographic attendance were collected through a postal questionnaire. Adjusted odds ratios and 95% confidence intervals were calculated using logistic regression. Tumors in HRT users were significantly smaller, more often of ductal histologic type and with lower grade and lower mitotic index compared to tumors in nonusers. Tumor characteristics did not vary significantly by HRT duration, regimen and route of administration, except for mitotic index, which was more often of score 2 in long-term users, and of score 3 in short-term users. Higher mammographic surveillance among HRT users did not explain our results. We conclude that tumors in HRT users have a more favorable prognostic profile regardless of duration, regimen and route of administration. These effects seem to be due to the influence of HRT on preexisting tumors causing their greater differentiation rather than earlier detection due to mammographic surveillance.

Estrogen metabolism genotypes, use of long-term hormone replacement therapy and risk of postmenopausal breast cancer.

Association between long-term hormone replacement therapy (HRT) use and increased risk of breast cancer is still under debate. Functionally relevant genetic variants within the estrogen metabolic pathway may alter exposure to exogenous sex hormones and affect the risk of postmenopausal breast cancer. We investigated the associations of common polymorphisms in 4 genes encoding key proteins of the estrogen metabolic pathway, duration of HRT use and their interactions with breast cancer risk. We studied 530 breast cancer cases and 270 controls of the same age and ethnicity participating in a case-control study of postmenopausal women. Duration of HRT use was ascertained through a postal questionnaire. Genotyping was conducted for CYP1B1 (rs1056836), COMT (rs4680), GSTP1 (rs1695) and MnSOD (rs4880) polymorphisms by PCR-based RFLP and TaqMan® allelic discrimination method. Adjusted odds ratios and 95% confidence intervals were calculated using logistic regression analysis. HRT use was significantly associated with decreased breast cancer risk (p<0.001). None of the polymorphisms studied was associated with breast cancer risk. A significant interaction was observed between MnSOD 47T>C and HRT use (pinteraction=0.036); the risk of breast cancer associated with long-term vs. short-term HRT use was decreased in women homozygous for the wild-type allele and increased in women with at least one variant allele of the MnSOD 47T>C polymorphism. Our results suggest that MnSOD 47T>C polymorphism in interaction with long-term HRT use may modify the risk of breast cancer.

IMP3, a proposed novel basal phenotype marker, is commonly overexpressed in adenoid cystic carcinomas but not in apocrine carcinomas of the breast.

Insulin-like growth factor-II mRNA-binding protein 3 (IMP3) is a member of the insulin-like growth factor-II signaling pathway, and has recently been described as a biomarker of basal-like breast carcinomas. This study explored IMP3 expression in adenoid cystic carcinomas of the breast, a special type of basal-like, triple-negative (estrogen receptor/progesterone receptor/human epidermal growth factor receptor 2/neu protein negative) carcinoma and compared it with a group of apocrine carcinomas, which are an example of estrogen receptor/progesterone receptor negative, special type of breast carcinoma. Eighteen breast adenoid cystic carcinomas (16 primary and 2 corresponding metastases) and 18 apocrine carcinomas (16 invasive and 2 in situ) were evaluated for the expression of IMP3 protein using immunohistochemical method. A cut-off value for IMP3 positivity was set at 10%. Thirteen of 16 (81.3%) primary adenoid cystic carcinomas overexpressed IMP3 protein, predominantly in membranous distribution. The mean percentage of positive cells among primary adenoid cystic carcinomas was 50%. Both metastatic adenoid cystic carcinomas also strongly overexpressed IMP3 protein (70% and 80% of the tumor cells, respectively). In contrast, only 4 of 16 invasive apocrine carcinomas (25%) exhibited IMP3 positivity with significantly lower percentage of positive cells (27%, P<0.001). Two in-situ apocrine carcinomas were negative. Our results indicate that IMP3 may be an additional basal-type marker in breast carcinoma whose expression can be occasionally seen in other types of breast carcinomas such as apocrine type.

ER-α36, a novel isoform of ER-α66, is commonly over-expressed in apocrine and adenoid cystic carcinomas of the breast.

BACKGROUND: ER-α36 is a novel 36 kDa isoform of the full-length oestrogen receptor alpha (ER-α66). ER-α36 primarily localises to the cytoplasm and the plasma membrane, and responds to membrane-initiated oestrogen and antioestrogen signalling pathways. AIM: To examine the expression of ER-α36 in apocrine and adenoid cystic carcinoma of the breast, both of which are consistently ER-α66 negative and currently lack effective targeted therapeutic options. METHODS: 19 pure apocrine carcinomas (17 invasive and two in-situ carcinomas) and 11 adenoid cystic carcinomas of the breast were evaluated for ER-α36 expression, along with expressions of ER-α66, progesterone receptor (PR) and androgen receptor (AR) using immunohistochemical methods. RESULTS: All pure apocrine carcinomas showed a characteristic steroid receptor expression profile (ER-α66 and PR negative, AR strongly positive). ER-α36 expression was detected in 18/19 pure apocrine carcinomas (94.7%, 95% CI 75.1 to 98.7) in predominantly membranous and cytoplasmic distribution. When positive, pure apocrine carcinomas uniformly (100% of cells) expressed ER-α36. All adenoid cystic carcinomas were uniformly negative for all three classic steroid receptors, but ER-α36 was detected in 8/11 cases (72.7%, 95% CI 42.8 to 90) with the similar sub-cellular pattern of expression as in the pure apocrine carcinomas. When positive, adenoid cystic carcinomas expressed ER-α36 in the majority of cells (average 76%). CONCLUSION: ER-α36, a novel isoform of ER-α66, is frequently over-expressed in apocrine and adenoid cystic carcinomas of the breast. These results indicate a potential for a novel targeted treatment in these cancers.

Adenoid cystic carcinomas of the breast have low Topo IIα expression but frequently overexpress EGFR protein without EGFR gene amplification.

Adenoid cystic carcinoma of the breast is a rare subtype of breast cancer with basal-like features. Published studies on breast adenoid cystic carcinoma are limited, resulting in relatively scarce information on the value of predictive tumor markers. We studied 20 primary cases of adenoid cystic carcinoma of the breast for expression of estrogen receptor, progesterone receptor, androgen receptor, epidermal growth factor receptor, HER-2/neu, and topoisomerase IIα using immunohistochemistry and fluorescent in situ hybridization methods. Estrogen and progesterone receptor expression were detected in 1 case each. All tumors were uniformly negative for Her-2/neu expression. Androgen receptor and topoisomerase IIα expression were weakly positive in three cases and 7 cases, respectively. Epidermal growth factor receptor overexpression was detected in 13 cases (65% of all cases). Amplification of TOP2A or HER-2/neu gene was not detected in any of the cases. Our study shows that the majority of adenoid cystic carcinomas of the breast do not overexpress Her-2/neu, topoisomerase IIα, or estrogen receptor, and thus, they are unlikely to respond to therapies targeting these proteins. However, these tumors frequently over-express epidermal growth factor receptor, indicating a potential benefit from anti-epidermal growth factor receptor therapy for patients with advanced adenoid cystic carcinomas of the breast.

A single-step procedure of recombinant library construction for the selection of efficiently produced llama VH binders directed against cancer markers.

Heavy chain antibodies are naturally occurring in camelidae (camels and llamas). Their variable domain (VHH) can be efficiently produced as a recombinant protein in E. coli with a large range of applications in the fields of diagnostics and immunotherapy. Standard cloning approach involves resolution of VHH from the heavy chain variable domain of conventional antibodies (VH) by a nested PCR amplification followed by a phage display based selection. Present work illustrates that in contrast to usual finding, specific, good affinity and efficiently expressed VH domain of conventional antibodies can be selected from the co-amplification products of VH and VHH cDNAs. Sequence analysis illustrated that following the two first rounds of selection against cancer markers, similar number of VH and VHH binders were observed. However, after a third round, the more specific binders directed against p53, VEGF, BCL-2 proteins surprisingly contain only VH specific hallmarks. Characterisation of the specificity, affinity and productivity of selected VH binders is described. Because llama VHs show higher sequence and structural homology with the human VH III group than llama VHHs (Vu et al., 1997), they constitute very interesting agents in therapeutic applications, especially in human immunotherapy and cancer treatment.

HER2 in well differentiated breast cancer: is testing necessary?

BACKGROUND: In addition to providing a timely and accurate diagnosis, pathologists routinely provide prognostic and predictive information to assist in the treatment of patients with invasive breast cancer. As our understanding of breast cancer at the molecular and genetic level improves, sophisticated new treatment options have become available to patients. The demonstrated improvements in disease-free and overall survival with the use of trastuzumab (Herceptin) has made HER2 testing a standard of care in the evaluation of patients with breast cancer. Specialized breast centers have accumulated sufficient experience to recognize that HER2 positive tumors tend to be of higher grade and to be estrogen receptor negative, whereas well-differentiated breast cancers rarely are HER2 positive. METHODS: To determine whether HER2 testing is necessary in well-differentiated breast cancer, we analyzed the frequency of HER2 positivity among 1,162 cases from 7 major breast centers or commercial laboratories in the United States and Europe. RESULTS: Well-differentiated breast cancers, defined by either nuclear grading or the Scarff-Bloom-Richardson system, rarely are HER2 positive (mean 1.6%, range 0-2.8%). CONCLUSIONS: Given the low rate of well differentiated HER2 positive tumors, falling within the range reported for false negative IHC tests for HER2, and the absence of published data demonstrating a beneficial effect of trastuzumab therapy in this subset of patients, HER2 testing should not be considered a standard of care for all patients with well-differentiated breast cancer.