Semir Vranic

A positive feedback loop of ER-α36/EGFR promotes malignant growth of ER-negative breast cancer cells.

It is prevailingly thought that estrogen signaling is not involved in development of estrogen receptor (ER)-negative breast cancer. However, there is evidence indicating that ovariectomy prevents the development of both ER-positive and -negative breast cancer, suggesting that estrogen signaling is involved in the development of ER-negative breast cancer. Previously, our laboratory cloned a variant of ER-α, ER-α36, and found that ER-α36 mediated nongenomic estrogen signaling and is highly expressed in ER-negative breast cancer cells. In this study, we found that ER-α36 was highly expressed in 10/12 cases of triple-negative breast cancer. We investigated the role of mitogenic estrogen signaling mediated by ER-α36 in malignant growth of triple-negative breast cancer MDA-MB-231 and MDA-MB-436 cells that express high levels of ER-α36 and found that these cells strongly responded to mitogenic estrogen signaling both in vitro and in vivo. Knockdown of ER-α36 expression in these cells using the small hairpin RNA method diminished their responsiveness to estrogen. ER-α36 physically interacted with the EGFR/Src/Shc complex and mediated estrogen-induced phosphorylation of epidermal growth factor receptor (EGFR) and Src. EGFR signaling activated ER-α36 transcription through an AP1 site in the ER-α36 promoter, and ER-α36 expression was able to stabilize EGFR protein. Our results, thus demonstrated that ER-α36 mediates nongenomic estrogen signaling through the EGFR/Src/ERK signaling pathway in ER-negative breast cancer cells and suggested that a subset of ER-negative breast tumors that expresses ER-α36, retains responsiveness to mitogenic estrogen signaling.

Assessment of HER2 gene status in breast carcinomas with polysomy of chromosome 17

The current study was performed to determine the impact of polysomy 17 on the interpretation of HER2 testing of invasive breast carcinomas using fluorescent in situ hybridization methods. Current American Society of Clinical Oncology/College of American Pathologists guidelines define HER2‐positive tumors as those with >6 HER2 genes per nucleus or those with HER2/CEP17 (chromosome 17) ratio >2.2. These guidelines are potentially contradictory in tumors with polysomy of chromosome 17.

EGFR and HER-2/neu expression in invasive apocrine carcinoma of the breast.

This study was undertaken to investigate epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER-2)/neu expression in a cohort of apocrine carcinomas of the breast with emphasis on the classification of the breast tumors with apocrine morphology. In total, 55 breast carcinomas morphologically diagnosed as apocrine were evaluated for the steroid receptor expression profile characteristic of normal apocrine epithelium (androgen receptor positive/estrogen receptor (ER) negative/progesterone receptor (PR) negative), and for the expression of EGFR and Her-2/neu proteins, and the copy number ratios of the genes EGFR/CEP7 and HER-2/CEP17. On the basis of the results of steroid receptors expression, 38 (69%) cases were classified as pure apocrine carcinoma (androgen receptor positive/ER negative/PR negative), whereas 17 (31%) were re-classified as apocrine-like carcinomas because they did not have the characteristic steroid receptor expression profile. Her-2/neu overexpression was observed in 54% of the cases (57% pure apocrine carcinomas vs 47% apocrine-like carcinomas). HER-2/neu gene amplification was demonstrated in 52% of all cases (54% pure apocrine carcinomas vs 46% apocrine-like carcinomas). EGFR protein (scores 1 to 3+) was detected in 62% of all cases and was expressed in a higher proportion of pure apocrine carcinomas than in the apocrine-like carcinomas group (76 vs 29%, P=0.006). In the pure apocrine carcinoma group, Her-2/neu and EGFR protein expression were inversely correlated (P=0.006, r=−0.499). EGFR gene amplification was observed in two pure apocrine carcinomas and one apocrine-like carcinoma. Polysomy 7 was commonly present in pure apocrine carcinomas (61 vs 27% of apocrine-like carcinomas; P=0.083) and showed a weak positive correlation with EGFR protein expression (P=0.025, r=0.326). Our study showed that apocrine breast carcinomas are molecularly diverse group of carcinomas. Strictly defined pure apocrine carcinomas are either HER-2-overexpressing breast carcinomas or triple-negative breast carcinomas, whereas apocrine-like carcinomas predominantly belong to the luminal phenotype. Pure apocrine carcinomas show consistent overexpression of either EGFR or HER-2/neu, which could have significant therapeutic implications.

Apocrine carcinoma of the breast: A comprehensive review

Apocrine carcinoma of the breast is a rare, special type of breast carcinoma showing distinct morphologic, immunohistochemical and molecular genetic features. Apocrine epithelium has a characteristic steroid receptor profile that is estrogen receptor and progesterone receptor negative and androgen receptor positive. This combination of morphologic and immunohistochemical characteristics is essential for the proper recognition of the apocrine carcinomas. Strictly defined, apocrine carcinomas express either Her-2/neu or EGFR, which along with androgen receptor positivity make patients with the apocrine carcinoma eligible for targeted therapies.

Molecular Profiling of Infiltrating Urothelial Carcinoma of Bladder and Nonbladder Origin

BACKGROUND Infiltrating UC represents the second most common genitourinary malignancy. Advanced UC has a poor prognosis and new treatments are needed. Molecular profiling of UC might identify biomarkers associated with targeted therapies or chemotherapeutics, providing physicians with new treatment options. MATERIALS AND METHODS Five hundred thirty-seven cases of locally advanced or metastatic UC of the bladder, 74 nonbladder, and 55 nonurothelial bladder cancers were profiled using mutation analysis, in situ hybridization, and immunohistochemistry assays for biomarkers predictive of therapy response. RESULTS Molecular profiling of UC showed high overexpression of topoisomerase 2α, common phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha and/or phosophatase and tensin homolog (PTEN) alterations in nonbladder (27%) and bladder UC (21%), and rare gene mutations across subtypes. Compared with nonbladder, bladder UC consistently exhibited more frequent abnormal protein expression, including HER2 (10% vs. 3%; P = .04), tyrosine protein c-Kit receptor kinases (11% vs. 5%), c-Met proto-oncogene, receptor tyrosine kinases (25% vs. 8%), androgen receptor (16% vs. 6%), O(6)-methylguanine-methyltransferase (63% vs. 43%), ribonucleotide reductase M1 (32% vs. 11%), Serum protein acidic and rich in cysteine (SPARC) (69% vs. 33%), and topoisomerase 1 (63% vs. 39%). Bladder UC also exhibited increased amplification of HER2 (12% vs. 2%; P = .06). CONCLUSION Comprehensive molecular profiling of UC identified a large number of biomarkers aberrations that might direct treatment in conventional chemotherapies and targeted therapies, not currently recommended in this population. As a group, bladder UC exhibited higher levels of actionable biomarkers, suggesting that UC from different primary sites and non-UC are driven by different molecular pathways. These differences could have clinical implications resulting in different treatment regimens depending on the site of origin of UC.

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.

Hamartomas, teratomas and teratocarcinosarcomas of the head and neck: Report of 3 new cases with clinico-pathologic correlation, cytogenetic analysis, and review of the literature

BackgroundGerm-cell tumors (GCT) are a histologically and biologically diverse group of neoplasms which primarily occur in the gonads but also develop at different extragonadal sites in the midline of the body. The head and neck region including the upper respiratory tract is a very rare location for such tumors in both children and adults, which can cause diagnostic and therapeutic difficulties.MethodsWe describe here two new cases of multilineage tumors including sinonasal teratocarcinosarcoma [SNTCS], and congenital oronasopharyngeal teratoma (epignathus) and compare their features with those of a new case of a rare salivary gland anlage tumor [SGAT], an entity for which the pathogenesis is unclear (i.e. hamartoma versus neoplasm). We correlate their presenting clinico-pathological features and compare histologic and cytogenetic features in an attempt to elucidate their pathogenesis and biologic potentials.Results and discussionCytogenetic analysis revealed chromosomal abnormalities only in the case of SNTCS that showed trisomy 12 and 1p deletion. Both cytogenetic abnormalities are characteristically present in malignant germ cell tumors providing for the first time evidence that this rare tumor type indeed might represent a variant of a germ cell neoplasm. The SGAT and epignathus carried no such cytogenetic abnormalities, in keeping with their limited and benign biologic potential.ConclusionThe comparison of these three cases should serve to emphasize the diversity of multilineage tumors (hamartomas and GCT) of the upper respiratory tract in regards to their biology, age of presentation and clinical outcomes. Malignant tumors of germ cell origins are more likely to affect adults with insidious symptom development, while benign tumors can nevertheless cause dramatic clinical symptoms which, under certain circumstances, can be fatal.

Hereditary Breast Cancer: Part II. Management of Hereditary Breast Cancer: Implications of Molecular Genetics and Pathology

Abstract:  Management of patients at high risk for hereditary breast cancer (HBC) must critically assess its phenotypic and genotypic heterogeneity, particularly evidenced by the varying spectra of cancer sites that are integral to the respective HBC syndromes. Targeted management must consider their biology, pathology, and molecular genetics, all in concert with their respective carcinogenic pathways, as they may differ significantly from one breast cancer syndrome to the next. A striking example of management differences pertains to BRCA1 and BRCA2 mutation‐positive breast cancers wherein those with BRCA1 mutations are frequently estrogen receptor (ER)‐negative in contrast to BRCA2 mutations which are more frequently ER‐positive; therein, significant differences exist with respect to anti‐estrogen therapy which will be more amenable to BRCA2 versus BRCA1 mutation carriers manifesting breast cancer. In turn, tumors that are negative for ER, PR, and Her2‐neu, often referred to as “triple negative” tumors, may also harbor a unique basal‐like gene expression profile and are characterized by poor prognosis wherein endocrine and/or Her2‐neu‐targeted therapies are not effective treatment options. A further confounder pertains to the lifetime risk for ovarian cancer, which differs strikingly between BRCA1 mutation carriers, who show a 40–60% lifetime risk, and their BRCA2 counterparts, who carry a lifetime risk of approximately 12–15% for ovarian cancer. It is clear that as we learn more about the biology and the molecular aspects of hereditary forms of breast cancer, it will be compelling for the clinician to integrate this knowledge with pharmacologic, radiologic, and surgical treatment options for these high‐risk patients.

Comprehensive profiling of metaplastic breast carcinomas reveals frequent overexpression of programmed death-ligand 1

Aims Metaplastic breast carcinoma (MBC) is a rare subtype of breast carcinoma less responsive to conventional chemotherapy than ductal carcinoma. In molecular terms, MBCs usually cluster with triple-negative breast cancers (TNBCs), but have a worse prognosis than TNBCs. Studies investigating MBCs for specific biomarkers of therapy response are rare and limited by the methodological approaches. The aim of the present study was to characterise MBCs on a molecular level and test programmed death-ligand 1 (PD-L1) biomarker expression in MBCs for future therapeutic interventions. Methods We profiled 297 samples (MBC (n=75), TNBC (n=106), human epidermal growth factor receptor 2 (HER2)-positive breast cancers (n=32) and hormone-positive breast cancers (n=84)) by next-generation sequencing. Immunohistochemistry for PD-L1 and programmed cell death 1 (PD-1) expression was performed using automated procedures. Results The most commonly mutated genes in MBCs included TP53 (56%) and PIK3CA (23%). Pathogenic mutations in other genes, including HRAS, FBXW7, PTEN, AKT1 and SMAD4, were rare. PD-L1 expression was detected in a significantly higher proportion of MBCs (46%) than in other subtypes (6% each in hormone-positive and HER2-positive breast cancers, and 9% in TNBC, not otherwise specified, p<0.001). PD-1-positive tumour infiltrating lymphocytes (TILs) varied greatly in MBCs. Conclusions Comprehensive profiling of a large cohort of this rare subtype of breast carcinoma highlighted the predominance of TP53 mutation and increased PD-L1 expression in carcinoma cells. These results can be exploited in clinical trials using immune checkpoint inhibitors.

Aggressive and nonaggressive translocation t(6;11) renal cell carcinoma: comparative study of 6 cases and review of the literature

UNLABELLED t(6;11) renal cell carcinoma (RCC) has been recognized as a rare and mostly nonaggressive tumor (NAT). The criteria for distinguishing aggressive tumors (AT) from NATs are not well established. A total of 6 cases were selected for the study. Five cases of t(6;11) RCCs behaved nonaggressively, and 1 was carcinoma with aggressive behavior. The tumors were analyzed morphologically using immunohistochemistry and by molecular-genetic methods. The specimen of aggressive t(6;11) RCC was from a 77-year-old woman who died of the disease 2.5 months after diagnosis. The specimens of nonaggressive t(6;11) RCCs were from 3 women and 2 men whose ages range between 15 and 54 years. Follow-up was available in all cases (2.5 months-8 years). The tumor size ranged from 3 to 14 cm in nonaggressive t(6;11) RCC. In the aggressive carcinoma, the tumor size was 12 cm. All tumors (6/6) were well circumscribed. Aggressive t(6;11) RCC was widely necrotic. Six (100%) of 6 all tumors displayed a solid/alveolar architecture with occasional tubules and pseudorosettes. Pseudopapillary formations lined by bizarre polymorphic cells were found focally in the aggressive t(6;11) RCC case. Mitoses, though rare, were found as well. All cases (AT and NAT) were positive for HMB-45, Melan-A, Cathepsin K, and cytokeratins. CD117 positivity was seen in 4 of 5 NATs, as well as in the primary and metastatic lesions of the AT. mTOR was positive in 2 of 5 NATs and vimentin in 4 of 5 NATs. Vimentin was negative in the primary lesion of the AT, as well as in the metastasis found in the adrenal gland. Translocation t(6;11)(Alpha-TFEB) or TFEB break was detected in 4 of 5 NATs and in the AT case. Aggressive tumor showed amplification of TFEB locus. Losses of part of chromosome 1 and chromosome 22 were found in 1 of 5 NATs and in the AT. CONCLUSIONS (1) Aggressive t(6;11) RCCs generally occur in the older population in comparison with their indolent counterparts. (2) In regard to the histologic findings in ATs, 3 of 5 so far published cases were morphologically not typical for t(6;11) RCC. Of the 3 cases, 2 cases lacked a small cell component and 1 closely mimicked clear cell-type RCC. (3) Necroses were only present in aggressive t(6;11) RCC. (4) Amplification of TFEB locus was also found only in the aggressive t(6;11) RCC.