α1 and α2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits α6 and β1, but not against α1 and α2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against β1, but not against α6 or α2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against α1 integrins impaired only cell adhesion to type IV collagen. Antibodies against α1, α2, α6, and β1, but not α5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins α1 and α2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against α1 and α2, but not α6 and β1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against α1 and α2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-α6 antibodies. Our data indicate that α1 and α2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas α6 integrins regulate cell motility. These results provide new insights into the specific functions of integrins during tumor cell invasion.

Pleomorphic lobular carcinoma of the breast: role of comprehensive molecular pathology in characterization of an entity

Immunohistochemical analysis of E-cadherin has changed the way lobular neoplasia is perceived. It has helped to classify difficult cases of carcinoma in situ with indeterminate features and led to the identification of new variants of lobular carcinoma. Pleomorphic lobular carcinoma (PLC) and pleomorphic lobular carcinoma in situ (PLCIS), recently described variants of invasive and in situ classic lobular carcinoma, are reported to be associated with more aggressive clinical behaviour. Although PLC/PLCIS show morphological features of classic lobular neoplasia and lack E-cadherin expression, it is still unclear whether these lesions evolve through the same genetic pathway as lobular carcinomas or are high-grade ductal neoplasms that have lost E-cadherin. Here we have analysed a case of extensive PLCIS and invasive PLC associated with areas of E-cadherin-negative carcinoma in situ with indeterminate features, using immunohistochemistry, chromogenic in situ hybridization, high-resolution comparative genomic hybridization (CGH) and array-based CGH. We observed that all lesions lacked E-cadherin and beta-catenin and showed gain of 1q and loss of 16q, features that are typical of lobular carcinomas but are not seen in high-grade ductal lesions. In addition, amplifications of c-myc and HER2 were detected in the pleomorphic components, which may account for the high-grade features in this case and the reported aggressive clinical behaviour of these lesions. Taken together, these data suggest that at least some PLCs may evolve from the same precursor or through the same genetic pathway as classic lobular carcinomas. Copyright (c) 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Stromal Myofibroblasts In Squamous Cell Carcinoma Of The Tongue In Young Patients - A Multicenter Collaborative Study.

The purpose of this study was to evaluate the presence of myofibroblasts, frequently associated with a more aggressive neoplastic behavior, in oral tongue squamous cell carcinoma (TSCC) of young patients and to compare with the distribution observed in older patients. Tumor samples from 29 patients younger than 40 years old affected by TSCC were retrieved and investigated for the presence of stromal myofibroblasts by immunohistochemical reactions against α smooth muscle actin, and the results obtained were compared to TSCC cases affecting older patients. No positive reaction could be found in the stromal areas devoid of neoplastic tissue, whereas myofibroblasts were present in 58.6% of the lesions in young patients and in 75.9% of the older ones. No significant difference was found when comparing the invasive front and the overall stroma of both groups, and no correlation could be obtained with stromal α smooth muscle actin expression, higher tumor grades or clinical stage (P > .05). There was no significant difference between the presence of stromal myofibroblasts of TSCC affecting young and old individuals.

Intravesical Bacillus Calmette-guérin Efficiently Reduces P70s6k1 But Not 4e-bp1 Phosphorylation In Nonmuscle Invasive Bladder Cancer.

We characterized the functional consequences of intravesical bacillus Calmette-Guérin on the molecular mechanism of the AKT/mTOR signaling pathway in nonmuscle invasive bladder cancer. To our knowledge this has not been reported previously. At age 7 weeks female Fischer 344 rats received 1.5 mg/kg MNU intravesically every other week for 6 weeks. They were randomized at 10 per group to MNU (0.2 ml vehicle), bacillus Calmette-Guérin (10(6) cfu Connaught strain), rapamycin (15 μg/ml) and bacillus Calmette-Guérin plus simultaneous rapamycin, each intravesically for 6 weeks. At week 15 the bladders were collected for histopathology, immunohistochemistry and immunoblot to determine p-AKT, Rictor, Raptor, p-4E-BP1, p-p70S6K1, p-AMPK-α, p-mTOR and p-p53. Papillary carcinoma (pTa) and high grade intraepithelial neoplasia (pTis) predominated in the MNU group while normal urothelium, papillary and flat hyperplasia were more common in treated groups. Nonmuscle invasive bladder cancer treated with bacillus Calmette-Guérin showed suppression of p70S6K1 but not 4E-BP1 phosphorylation. This suggests that 4E-BP1 is regulated differently than p70S6K1, escaping the bacillus Calmette-Guérin action that occurs in a mTOR independent manner. The association of bacillus Calmette-Guérin with rapamycin but not rapamycin monotherapy affected p70S6K1 and 4E-BP1 phosphorylation with no features of in situ carcinoma (pTis). The activation status of p70S6K1 and 4E-BP1 might be used to stratify patients who could benefit from targeting such molecular elements with multitarget/multidrug intravesical therapy. In the future 4E-BP1 might be a worthwhile new target for bacillus Calmette-Guérin refractory nonmuscle invasive bladder cancer.

Carcinomas mamários de tipo basal: perfil clínico-patológico e evolutivo

OBJETIVO: Investigar a frequência de carcinomas mamários de fenótipo basal em uma série de tumores triplo-negativos (TTN), definidos pela negatividade para receptores de estrógeno (RE), de progesterona (RP) e HER2. MÉTODOS: Selecionamos 140 TTN, obtendo-se características clínico-patológicas e sobrevida. Microarranjo de tecido (2 cilindros de cada tumor) foi construído e submetido à imunoistoquímica para RE, RP, HER2, citoqueratinas (Cks) 5 e 14, EGFR, p63 e p53. Consideramos carcinomas de fenótipo basal os tumores negativos para RE, RP e HER2, e positivos para CK5. RESULTADOS: Encontramos 105 carcinomas de fenótipo basal entre 140 TTN (frequência=75%). A idade média das pacientes foi de 54,8 anos, sendo que 34,3% estavam na pré-menopausa. A maioria dos tumores foi classificada como carcinoma ductal invasor de alto grau. Os TTN exibiram positividade para CK5 (75,0%), CK14 (29%), EGFR (36,4%), p63 (28,6%) e p53 (67,1%). Estadiamento avançado da doença foi observado em 52 pacientes (50%), com diâmetro tumoral maior que 5 cm em 41 casos (39%) e metástases axilares em 61 casos (59,2%). Seguimento clínico foi obtido em 89 pacientes (média=51 meses). Destas, 45 pacientes (50,5%) evoluíram sem doença; 6 (6,7%) estavam vivas com doença e 38 (42,6%) morreram pelo câncer. Recidiva sistêmica ocorreu em 42 pacientes (47,1%), sendo pulmões, cérebro e ossos os principais sítios de metástases. As médias das sobrevidas global e livre de doença foram de 36 e 28 meses, respectivamente. CONCLUSÕES: Nosso estudo confirma comportamento clínico agressivo e elevada frequência dos carcinomas de fenótipo basal entre os TTN, semelhante ao descrito em casuísticas norte-americanas e europeias.

Interaction between polymorphisms of the Human Leukocyte Antigen and HPV-16 Variants on the risk of invasive cervical cancer

Background: Persistent infection with oncogenic types of human papillomavirus (HPV) is the major risk factor for invasive cervical cancer (ICC), and non-European variants of HPV-16 are associated with an increased risk of persistence and ICC. HLA class II polymorphisms are also associated with genetic susceptibility to ICC. Our aim is to verify if these associations are influenced by HPV-16 variability. Methods: We characterized HPV-16 variants by PCR in 107 ICC cases, which were typed for HLA-DQA1, DRB1 and DQB1 genes and compared to 257 controls. We measured the magnitude of associations by logistic regression analysis. Results: European ( E), Asian-American ( AA) and African (Af) variants were identified. Here we show that inverse association between DQB1*05 ( adjusted odds ratio [ OR] = 0.66; 95% confidence interval [CI]: 0.39-1.12]) and HPV-16 positive ICC in our previous report was mostly attributable to AA variant carriers ( OR = 0.27; 95% CI: 0.10-0.75). We observed similar proportions of HLA DRB1*1302 carriers in E-P positive cases and controls, but interestingly, this allele was not found in AA cases ( p = 0.03, Fisher exact test). A positive association with DRB1*15 was observed in both groups of women harboring either E ( OR = 2.99; 95% CI: 1.13-7.86) or AA variants ( OR = 2.34; 95% CI: 1.00-5.46). There was an inverse association between DRB1*04 and ICC among women with HPV-16 carrying the 350T [83L] single nucleotide polymorphism in the E6 gene ( OR = 0.27; 95% CI: 0.08-0.96). An inverse association between DQB1*05 and cases carrying 350G (83V) variants was also found ( OR = 0.37; 95% CI: 0.15-0.89). Conclusion: Our results suggest that the association between HLA polymorphism and risk of ICC might be influenced by the distribution of HPV-16 variants.

Probability of axillary node involvement in patients with tubular carcinoma of the breast

The aim of this study was to investigate the frequency of axillary metastasis in women with tubular carcinoma (TC) of the breast. Women who underwent axillary dissection for TC in the Western Sydney area (1984-1995) were identified retrospectively through a search of computerized records. A centralized pathology review was performed and tumours were classified as pure tubular (22) or mixed tubular (nine), on the basis of the invasive component containing 90 per cent or more, or 75-90 per cent tubule formation respectively. A Medline search of the literature was undertaken to compile a collective series (20 studies with a total of 680 patients) to address the frequency of nodal involvement in TC. A quantitative meta-analysis was used to combine the results of these studies. The overall frequency of nodal metastasis was five of 31 (16 per cent); one of 22 pure tubular and four of nine mixed tumours (P = 0.019). None of the tumours with a diameter of 10 mm or less (n = 16) had nodal metastasis compared with five of 15 larger tumours (P = 0.018). The meta-analysis of 680 women showed an overall frequency of nodal metastasis in TC of 13.8 (95 per cent confidence interval 9.3-18.3) per cent. The frequency of nodal involvement was 6.6 (1.7-11.4) per cent in pure TC (n = 244) and 25.0 (12.5-37.6) per cent in mixed TC (n = 149). A case may be made for observing the clinically negative axilla in women with a small TC (10 mm or less in diameter).

Immunohistochemical analysis of p53, APE1, hMSH2 and ERCC1 proteins in actinic cheilitis and lip squamous cell carcinoma

Aims: This study has compared the tissue expression of the p53 tumour suppressor protein and DNA repair proteins APE1, hMSH2 and ERCC1 in normal, dysplastic and malignant lip epithelium. Methods and results: Morphological analysis and immunohistochemistry were performed on archived specimens of normal lip mucosa (n = 15), actinic cheilitis (AC) (n = 30), and lip squamous cell carcinoma (LSCC) (n = 27). AC samples were classified morphologically according to the severity of epithelial dysplasia and risk of malignant transformation. LSCC samples were morphologically staged according to WHO and invasive front grading (IFG) criteria. Differences between groups and morphological stages were determined by bivariate statistical analysis. Progressive increases in the percentage of epithelial cells expressing p53 and APE1 were associated with increases in morphological malignancy from normal lip mucosa to LSCC. There was also a significant reduction in epithelial cells expressing hMSH2 and ERCC1 proteins in the AC and LSCC groups. A higher percentage of malignant cells expressing APE1 was found in samples with an aggressive morphological IFG grade. Conclusions: Our data showed that epithelial cells from premalignant to malignant lip disease exhibited changes in the expression of p53, APE1, hMSH2 and ERCC1 proteins; these molecular change might contribute to lip carcinogenesis.

Acinar cell carcinoma of the pancreas: is the absence of neuroendocrine component related to a more malignant behavior?

Background/Aims: Acinar cell carcinomas are uncommon malignant tumors of the pancreas, accounting for 1-2% of all the cases of exocrine pancreatic tumor. Some authors have estimated acinar cell tumors to be as aggressive as ductal adenocarcinoma of the pancreas whereas other series showed acinar cell tumors to have a favorable clinical outcome. This discrepancy in prognosis may be related to the cellular components of the tumor. Methodology: With the aim to evaluate the possible relationship between the presence of neuroendocrine differentiation and behavior of these tumors, the authors reviewed all patients presenting acinar cell carcinoma of the pancreas in the last 5 years with emphasis in the immunohistochemical evaluation. Results: Four patients presented neuroendocrine differentiation on immunohistochemical evaluation and had a more benign outcome. Two patients without neuroendocrine component had a disseminated disease at presentation. This data suggests that this tumor is less aggressive than ductal adenocarcinoma and even with nodal involvement, long term survival after complete resection can be achieved. Conclusions: It is possible that the absence of neuroendocrine component may be related to a less favorable outcome and adjuvant therapy may be necessary. Due to the rarity of this pancreatic tumor, this relationship remains to be confirmed with a multicentric study including a larger number of patients.

Extremely late development of pituitary carcinoma after surgery and radiotherapy

Introduction Pituitary carcinomas account for 0.1 or 0.2% of pituitary tumors. The authors report a rare case of a pituitary carcinoma mimicking a radio-induced meningioma. Case report Fifty-five years-old male presents a previous history of transcranial surgery in 1983 for invasive pituitary adenoma followed by whole-brain radiotherapy (5100 cGy). After three years he presented worsening of visual deficits and MRI evidenced recurrence of the lesion. In 1992, he underwent a transcranial approach to treat recurrent supraselar disease, followed by stereoctatic radiotherapy. In 2006, clinical condition was stable; however three right frontal extra-axial lesions were diagnosed by MRI, compatible with meningioma. The histological examination revealed pituitary adenoma. No lesions were found in craniospinal axis. Further treatment was not recommended by radiotherapists due previous actinic treatments. Two years radiological follow-up revealed no recurrence. Conclusion In these high risk cases, active and constant surveillance must be pertained, regardless the time of follow-up.

Collagen Type I may Influence the Expression of E-Cadherin and Beta-catenin in Carcinoma Ex-pleomorphic Adenoma

Carcinoma ex-pleomorphic adenoma (CXPA) is an aggressive salivary gland malignancy, usually derived from a long-standing or a recurrent benign tumor, the pleomorphic adenoma (PA). In the context of dynamic reciprocity, changes in the composition and structure of extracellular matrix proteins and cell surface receptors have been frequently associated with dysfunctional adhesion and invasive behavior of tumor cells. It is not fully understood if these changes are involved in the conversion of PA to CXPA. In this study, different progression stages of CXPA were investigated regarding the expression of the major extracellular matrix proteins, collagen type I, and of E-cadherin and beta-catenin, the components of adherens junctions. By immunohistochemical analysis, we have demonstrated that direct contact of tumor cells with fibrillar type I collagen, particularly near the invasive front and in invasive areas prevailing small nests of CXPA cells, could be associated with reduced expression of the E-cadherin and beta-catenin adhesion molecules and with invasive behavior of epithelial; but not of CXPA with myoepithelial component. Our results also suggested that this association could depend on the organization of collagen molecules, being prevented by high-order polymeric structures. These findings could implicate the local microenvironment in the transition from the premalignant PA to invasive CXPA.

Tenascin and fibronectin expression in carcinoma ex pleomorphic adenoma

This study was conducted to analyze the participation of tenascin and fibronectin, components of the extracellular matrix. in different types of carcinoma ex pleomorphic adenoma (CXPA). Seventeen cases of CXPA, classified according to the presence of epithelial and myoepithelial cells and the degree of invasion-intracapsular, minimally, and frankly invasive carcinoma-were immunohistochemically labeled for tenascin and fibronectin. Normal salivary gland included in the specimens showed tenascin only around the excretory duct, and fibronectin slightly expressed all over the stroma of the gland. In reminiscent pleomorphic adenoma, tenascin and fibronectin were observed around tubular structures and in the stroma. Both tenascin and fibronectin were expressed in all the CXPA studied. In areas of in situ carcinoma of the intracapsular type, the expression of these extracellular matrix proteins was enhanced compared with areas of residual pleomorphic adenoma. In intracapsular and minimally invasive types of CXPA, some areas of the tumor border presented tenascin and no fibronectin, pattern that may represent the real invasive front. In frankly invasive CXPA type with only epithelial component, fibronectin was strongly observed in a fibrillar network pattern, and tenascin was only focal. In frankly invasive type with myoepithelial component, tenascin staining was very strong and diffuse. This study showed different patterns of expression of tenascin and fibronectin along the process of tumorigenesis and tumor progression in CXPA, a fact that might play a role in invasion properties of these tumors.

HER2 Testing in Breast Carcinoma Very Low Concordance Rate Between Reference and Local Laboratories in Brazil

Breast cancer accounts for approximately one quarter of all cancers in females. HER2 gene amplification or HER2 protein overexpression, detected in about 20% of breast carcinomas, predicts a more aggressive clinical course and determines eligibility for targeted therapy with trastuzumab. HER2 testing has become an essential part of the clinical evaluation of all breast carcinoma patients, and accurate HER2 results are critical in identifying patients who may be benefited from targeted therapy. This study investigated the concordance in the results of HER2 immunohistochemistry assays performed in 500 invasive breast carcinomas between a reference laboratory and 149 local laboratories from all geographic regions of Brazil. Our results showed an overall poor concordance (171 of 500 cases, 34.2%) regarding HER2 results between local and reference laboratories, which may be related to the low-volume load of HER2 assays, inexperience with HER2 scoring system, and/or technical issues related to immunohistochemistry in local laboratories. Standardization of HER2 testing with rigorous quality control measures by local laboratories is highly recommended to avoid erroneous treatment of breast cancer patients.

Classical and non-classical HLA molecules and p16(INK4a) expression in precursors lesions and invasive cervical cancer

Objectives: Viruses and turnout cells may regulate the expression of HLA molecules on the cell surface to escape immune system surveillance. Absence of classical HLA class I molecules may impair the action of specific cytotoxic cells, whereas non-classical HLA class I molecules may regulate innate and adaptive immune cells. We assess here the possible associations between classical/non-classical class I HLA and p16(INK4a) molecule expression in cervical biopsies of women infected with HPV, stratified according to grade of the lesion and HPV type. Study design: Cervical biopsies (N = 74) presenting cervical intraepithelial neoplasia grade 1 (CIN1) (n = 31), CIN2-3 (n = 19), and invasive cancer (n = 14) were evaluated alongside 10 normal cervical specimens. Results: HLA-A/B/C/G staining was observed in the early stages of HPV infection. A significant association was detected between HLA-A/B/C staining and HPV16/18 infection (OR = 0.12, 95%CI: 0.0163-0.7899; p = 0.04). HLA-E expression increased with the progression of the lesion (chi(2)-test for trend = 4.01; p = 0.05), and a significant association was found between HLA-E staining and HPV16/18 infection (OR = 11.25, 95%CI: 2.324-54.465; p = 0.003). Irrespective of the grade of the lesion, HLA-A/B/C staining and p16(INK4a) presented a good concordance (Kappa: 0.67). Conclusions: HLA-E overexpression seemed to be associated with invasive cancer and HPV16/18 infection. (C) 2008 Elsevier Ireland Ltd. All rights reserved.