[Adenoid cystic carcinoma cells produce exosomes that promote tumor cell proliferation].

OBJECTIVE: To observe the effect of exosomes released by adenoid cystic carcinoma (ACC) cell line SACC-83 on the proliferation of ACC cells. METHODS: Exosomes were isolated from SACC-83 cell culture supernatants using total exosome isolation reagents. The whole-mount exosomes were characterized using transmission electron microscope and Western blotting. The exosomes were labeled with green fluorescent dye PKH67 and co-cultured with SACC-83 cells for 48 h, followed by staining with Alexa Fluor 594 phalloidin and DAPI to observe exosome uptake by the cells using laser scanning confocal microscopy (LSCM). The cell proliferation was assessed using MTT assay and wound healing assay, and the expressions of ERK and P-ERK in the co-cultured SACC-83 cells were detected using Western blotting. RESULTS: The exosomes isolated from SACC-83 cells showed a size range of 30-100 nm and expressed the exosomal markers CD9, CD63 and TSG101. LSCM showed exosome uptake by SACC-83 cells, which exhibited accelerated proliferation and significantly enhanced P-ERK expression (P < 0.05) without significant changes in ERK expression. CONCLUSIONS: SACC-83 cells produce exosomes that promote the tumor cell proliferation and enhances the cellular expression of P-ERK, suggesting a potential role of MAPK/ERK pathway activation in exosome-mediated acceleration of ACC cell proliferation.

Carcinoma adenoide quístico extrasalival. Presentación de un caso / Extra salivary gland presentation of adenoid cystic carcinoma. A case report

Se presenta un caso infrecuente de carcinoma adenoide quístico en fosa nasal derecha donde se realizó una correlación patrón histológico de crecimiento/pronóstico. Por el estudio clínico, histológico e histoquímico, con determinación del grado histopatológico tumoral y estadificación para tumores malignos de cavidad nasal se diagnosticó carcinoma adenoide quístico grado iii estadio T2 con importante componente sólido, invasión perineural, compromiso de márgenes quirúrgicos y metástasis pulmonar(AU)

A rare case of adenoid cystic carcinoma (ACC) in the right nasal fossa is reported. A clinicopathological study of the correlation of growth pattern/prognosis was carried out. Taking into account the clinical stage, histology, histochemistry, tumour grading and staging for malignant tumours of the nasal cavity, a grade lII, stage 2 ACC with a marked solid component, perineural invasion, involvement of surgical borders and pulmonary metastases was diagnosed(AU)

Primary cutaneous adenoid cystic carcinoma.

Primary cutaneous adenoid cystic carcinoma is a rare, slow-growing malignancy first described by Boggio in 1975. This tumor characteristically consists of basophilic cells with a distinct adenoid or cribriform pattern in the mid to deep reticular dermis. Modified myoepithelial cells with prominent basement membrane material often surround true lumina. Definitive diagnosis relies on the characteristic histologic features and the exclusion of metastatic disease. We describe two patients who presented with painful papules of the scalp and were successfully treated with wide local excision.

Secretion of collagen I and tenascin is modulated by laminin-111 in 3D culture of human adenoid cystic carcinoma cells.

Adenoid cystic carcinoma is a frequent malignant salivary gland neoplasm with high levels of recurrence and metastasis. This neoplasm expresses prominent extracellular matrix (ECM). We are studying regulatory mechanisms underlying secretion of ECM molecules in adenoid cystic carcinoma. We have previously demonstrated that laminin modulates the phenotype of a human adenoid cystic carcinoma (CAC2) cell line. Thus, this molecule would be a good candidate to regulate secretion of ECM molecules in these cells. Here we analysed the role played by laminin-111 [formerly laminin-1; Aumailley et al. (2005). Matrix Biol. 24, 326] stimulating secretory activity of CAC2 cells. Three-dimensional cultures of cells in laminin-111 (treated) or agarose (controls) were studied by light and electron microscopy. Ultrastructural analysis of CAC2 cells grown within laminin-111 showed pseudocysts filled with secretory-like material. Cells exhibited prominent and dilated endoplasmic reticulum and coated and uncoated vesicles. Ultrastructural findings suggested that laminin-111 induced secretory activity in CAC2 cells. We further investigated this point by light microscopy, immunofluorescence and confocal microscopy. Histochemistry showed periodic acid-Schiff (PAS)-positive diastase-resistant material in CAC2 cells treated by laminin-111. This material could represent laminin-induced secretion of ECM molecules. We searched for collagen I and tenascin in CAC2 cells treated by laminin-111. Confocal microscopy and immunoblot showed that laminin-111 enhanced secretion of collagen I and tenascin in CAC2 cells. We suggest that laminin-111 modulates secretion of collagen I and tenascin in cells derived from human adenoid cystic carcinoma.

Distinguishing adenoid cystic carcinoma from cylindromatous adenomas in salivary fine-needle aspirates: the cytologic clues and their ultrastructural basis.

The utilization of fine-needle aspiration (FNA) biopsy in salivary tumors is hindered by the reluctance of many cytopathologists to report adenoid cystic carcinoma (ACC) because its cylindromatous stroma is observed occasionally in pleomorphic adenoma (PA) and basal cell adenoma (BA), and a diagnosis of ACC results in radical surgery. The aim of this study is to identify dependable features to distinguish the look-alike entities and illustrate their ultrastructural base. We compared 20 cases of ACC to 15 cases of cylindromatous PA and 9 cases of BA. All were direct smears stained with Diff-Quik, hematoxylin and eosin, Papanicolaou, or Ultrafast Papanicolaou (UFP) stain. In addition to the presence of cylindromatous pattern, the amount of cytoplasm in the neoplastic cells and nuclear features were compared. Tissue was dissected from paraffin blocks and processed for electron microscopy in selected cases. The difference in nuclear features can be distinguished in UFP-stained smears and electron microscopy. The nuclei of ACCs were heterochromatic with coarse chromatin and irregular nucleoli, whereas the nuclei of PAs were euchromatic with fine chromatin and small compact nucleoli. The nuclei of BAs were hyperchromatic but finely textured. The cytoplasm of PAs was detectable with every stain at 40x objective, but the cytoplasm of BAs required UFP stain and 100x objective to be detected. The cytoplasm of majority of neoplastic cells of ACCs are invisible, because the thin rim of cytoplasm measured <1 microm ultrastructurally, well beyond the resolution of a light microscope. Rare cohesive fragment of epithelial cells in ACC have scanty blue cytoplasm in UFP stain and can be recognized as ductal cells. In conclusion, in our analysis of salivary tumors with a cylindromatous pattern, the seemingly naked nuclei of neoplastic cells with their coarse nuclear chromatin and irregular nucleoli, as revealed by the UFP stain, reliably distinguished ACC from cylindromatous adenomas.

Basaloid squamous cell carcinoma of the esophagus with or without adenoid cystic features.

CONTEXT: Basaloid squamous cell carcinoma (BSCC) of the esophagus is a rare malignant tumor that morphologically could bear some resemblance to adenoid cystic carcinoma (ACC) originating from salivary glands. OBJECTIVE: The purpose of this study is to describe the histologic, immunohistochemical, and ultrastructural findings of BSCCs of the esophagus, with an emphasis on comparing tumors with or without adenoid cystic features. DESIGN: We reviewed 239 cases of primary esophageal carcinoma and detected 12 cases (5%) of BSCC. The light and electron microscopic findings and immunocytochemical localization of various antigens, including cytokeratins (AE1, AE3), carcinoembryonic antigen, epithelial membrane antigen, S100, smooth muscle actin, and p53, were examined in these BSCC cases. RESULTS: Histologically, all BSCCs were composed of solid lobules or nests of basaloid cells with well-demarcated outlines surrounded by a fibrous stroma. Seven of 12 tumors showed areas of ACC-like features, that is, cribriform-like pseudoglandular lumina formation and hyaline material surrounding the tumor nests, whereas the remaining 5 tumors were apparently pure basaloid carcinomas. These 2 groups of tumors were histologically and immunohistochemically identical in many aspects, namely, high-grade nuclei of the tumor cells with frequent mitoses, abundant comedo-type necrosis, focal areas of concomitant squamous differentiation, consistent immunoreactivity for cytokeratins, and poor or absent staining for S100 and smooth muscle actin. Ultrastructurally, the basaloid tumor cells exhibited relatively undifferentiated cellular characteristics and undeveloped cell organelles. CONCLUSION: Basaloid squamous cell carcinomas of the esophagus frequently have an intimate association with ACC-like patterns, but their histologic, immunocytochemical, and ultrastructural features correspond more to poorly differentiated squamous cell carcinoma than to salivary gland ACC. This distinction is important because genuine ACC is much less aggressive than BSCC.

Brefeldin-A induces apoptosis in human adenoid cystic carcinoma cultured cells.

Adenoid cystic carcinoma (ACC) of salivary glands is characterized by a high rate of local recurrences, neurotropism and metastasis. ACC long-term survival rate is not promising. Thus, different chemotherapeutical approaches had been proposed for this neoplasm, including apoptosis induction by different drugs. This work evaluates the efficacy of Brefeldin-A (BFA), a potent apoptosis inducer, on ACC cultured cells (CAC2 cell line). CAC2 cells were treated with a 375 microM BFA solution in serum-free medium during 18 h. CAC2 cells grown in DMEM supplemented with 10% fetal bovine serum served as controls. Apoptotic cell recognition and counting were carried out through Hoechst staining. Transmission electron microscopy and immunofluorescence assessed the effect of BFA on CAC2 cells phenotype. Treated cultures showed a high apoptotic index presenting +/-30% of cells in evident apoptosis, when compared to controls. Apoptotic CAC2 cells also exhibited different alterations such as cytoplasmic vesicles formation and mitochondrial changes. Cultured ACC cells are strongly susceptible to apoptosis induction under BFA treatment, which may constitute a promising tool in further chemotherapeutical approaches.

[Correlation between ultrastructural changes and the presence of metastases in adenoid cystic carcinoma of salivary glands]. / Badania ultrastrukturalne a wystepowanie przerzutów w wezlach chlonnych w raku gruczolowato-torbielowatym slinianek.

Adenoid-cystic carcinoma is a malignant epithelial neoplasm which has different histological types. Still, an open question is, whether adenoid-cystic carcinoma of the salivary glands with metastases to lympho nodes and specific micro- and macroscopic features, allows us to define their progression. A group of 46 patients with adenoid-cystic cancer of the salivary glands was studied and was subjected to histological and ultrastructural assessment. In analysed group in 12 patient metastases to lympho nodes were confirmed. In 10 cases it was solid type of tumour and in 2 canaliculars type. In tumours with metastases to lympho nodes solid types prevailed and there was no a typical cribriform type. In all cases they were found fields of mixted texture of the tumours structure.

[Paclitaxel-induced apoptosis in ACC-2 cells is associated with the arrest of G(2)/M].

OBJECTIVE: To investigate whether paclitaxel (Taxel) can efficiently induce apoptosis of ACC-2 or not, and to study the relation of apoptosis and arrest of cell mitosis. METHODS: Paclitaxel-induced arrest of cell mitosis and apoptosis of ACC-2 cells in various concentration and different treat time were determined using transmission electron microscope (TEM), fluorescence microscope, flow-cytometry and DNA agarose gel electrophoresis technique. RESULTS: Under fluorescence microscope, apoptotic cells were green with irregular clumping of nucleus chromatin, or even nuclear chromatin segregation. The typical ultra-structural changes of apoptosis observed by TEM were cell compaction, margination of nuclear chromatin, condensation of cytoplasm, protuberances and apoptotic body. "DNA Ladder" was absent in agarose gel electrophoresis of DNA extracted from culture of ACC-2 cells and paclitaxel-induced ACC-2 cells. "Sub-G(1)" phase peak of ACC-2 cells induced by 50 nmol/L paclitaxel in 48 h and 72 h was 17.13% and 16.26%, respectively. The percentage of G(2)/M phase increased in accordance with raise of the paclitaxel concentration and prolongation of treatment. The typical ultra-structural changes of apoptosis were observed in case that G(2)/M phase was arrested. CONCLUSIONS: Paclitaxel could induce apoptosis of ACC-2 cells. Arrest of G(2)/M phase might induce apoptosis of ACC-2 cells.

Defective laminin 5 processing in cylindroma cells.

Cylindromas are benign skin tumors occurring as multiple nodules characteristically well circumscribed by an excess of basement membrane-like material. To determine the molecular defects leading to extracellular matrix accumulation, the ultrastructural, immunological, and biochemical properties of cylindroma tissue and isolated cells were analyzed. In cylindromas, hemidesmosomes are reduced in number, heterogeneous and immature compared to the normal dermal-epidermal junction. Expression of the alpha6beta4 integrin in tumor cells is weaker than in basal keratinocytes of the epidermis. Moreover, although in the epidermis alpha2beta1-integrin expression is restricted to the basal cell layer, it is found in all neoplastic cells within the nodules. Laminin 5 is present throughout the whole thickness of the basement membrane-like zone whereas laminin 10 is restricted to the interface adjacent to the tumor cells. Furthermore, laminin 5 is not properly processed and most of the alpha3A and gamma2 laminin chains remain as 165-kd and 155-kd polypeptides, respectively. Mature laminin 5 is thought to be necessary for correct hemidesmosome and basement membrane formation and its abnormal processing, as well as the low expression of alpha6beta4 integrins, could explain the lack of mature hemidesmosomes. Together, the results show that multiple molecular defects, including alteration of laminin 5 and its integrin receptors, contribute to structural aberrations of the basement membrane and associated structures in cylindromas.

Adenoid basal carcinoma of the uterine cervix: a case report with ultrastructural findings.

Adenoid basal carcinoma of the uterine cervix is a rare tumor with a favorable prognosis. A case of adenoid basal carcinoma (ABC) of the uterine cervix was studied using light and electron microscopy. The patient was a 74-year-old Japanese woman who had undergone hysterectomy due to cervical intraepithelial neoplasia 3. Incidentally, ABC was found in the resected uterus. The tumor cells made small nests and infiltrated the cervical portion of the uterus. In the nests, glands, cribriform patterns with glandlike structures, and squamous differentiation were seen. Immunohistochemically, the glandlike structures were positive for laminin and type IV collagen. Ultrastructurally, the tumor cells had irregular nuclei, scanty cytoplasm, and cribriform patterns in which glandlike structures were covered with basal lamina. No myoepithelial differentiation of the tumor cells was seen. These findings suggest a similarity between adenoid basal carcinomas and adenoid cystic carcinomas. Furthermore, both tumors are considered to originate in the reserve cells of the uterine cervix. Because their outcomes are different, they should be distinguished from each other.

Ultrastructural localization of E-cadherin and alpha-/beta-catenin in adenoid cystic carcinoma.

AIMS: To investigate the disturbance of intercellular adhesion in adenoid cystic carcinoma (ACC), we examined the ultrastructural localization of E-cadherin (E-cad), alpha-catenin (alpha-cat) and beta-catenin (beta-cat) in ACC, and compared it with that in the normal labial gland. METHODS AND RESULTS: Using immuno-electron microscopy, in the normal labial gland, E-cad was found to be uniformly distributed along the plasmalemma, where cells were in close contact with each other, with junctional complexes, desmosomes and interdigitations; expression of alpha-cat and beta-cat was also detected. In ACC, which was classified into tubular, cribriform and trabecular types, E-cad expression seemed not to be uniform, but was observed to be along the plasmalemma where cell-to-cell contact was made. On the other hand, expression of alpha-cat or beta-cat was uneven in the trabecular-type cells which were very slender and grew in an infiltrative scattered pattern into the extracellular matrix; that was absent in the cribriform-type cells which made contact with each other mostly at the tip of the cytoplasmic processes. CONCLUSION: These findings suggest that the neoplastic cells of ACC express E-cad for use in intercellular adhesion, but the cadherin-catenin complex might not operate properly, which is the cause of neoplastic cell dissociation, followed by invasion and metastasis.

Myoepithelium in salivary and mammary neoplasms is host-friendly.

This commentary relates to ameliorative effects of myoepithelial cells in carcinomas of salivary glands and the breast as viewed not only by proliferative characteristics, but also by laboratory experiments and clinicopathologic evidence. The tumor suppressor action of myoepithelium is, in part, associated with its matrix-synthesizing and proteinase inhibitor properties. Loss of the myoepithelial phenotype yields a more aggressive carcinoma with enhanced invasive and metastatic capability.

[The ultrastructure of membrane component in adenoid cystic carcinoma of salivary gland].

OBJECTIVE: To study morphological variations of basment membrane component (BMC) for determination of invasion and vascular metastasis in adenoid cystic carcinoma (ACC). METHODS: The BMC of 8 cases in ACC and 2 cases of normal parotid gland were observed by LM and EM. RESULTS: The BMC surrounding tumor mass and strands showed multi-layered or dissolution, pseudopodia were seen extended from tumor cells, and contained numerous microvesicles. If the tumor cell attached blood vessels, the collagenous fibril were dissoluted and BMC were lost. CONCLUSION: The tumor cell may release some digestive enzymes which may be able to dissolve BMC and collagenous fibrils and invade into blood vessels and metastasis take place.

Cilindromatose: atualizaçäo clínica e epidemiológica / Cylindromatosis: clinical and epidemiological up-date

A proposta deste trabalho é fornecer uma revisäo e informaçöes atualizadas sobre a síndrome conhecida como cilindromatose ou tumor em turbante. A cilindromatose é uma desordem genética autossômica dominante que possui duas formas de manifestaçäo, uma de origem hereditária e a outra esporádica. A clínica se baseia no surgimento de tumores oriundos das glândulas sudoríparas écrinas que tendem a se concentrar na cabeça, principalmente, couro cabeludo e pescoço.

Prognostic significance of nucleolar organizer regions in adenoid cystic carcinomas of the head and neck.

OBJECTIVE: To determine the prognostic use of nucleolar organizing region (AgNOR) counts and clinical and histopathological features in adenoid cystic carcinoma. DESIGN: Argyrophilic staining was applied to ordinary formalin-fixed, paraffin-embedded specimens and evaluated to obtain the mean number of AgNORs and the percentage of nuclei with more than 1 (pAgNOR > 1), more than 2, more than 3, and more than 4 AgNORs. RESULTS: Using the log rank test, the mean AgNOR count showed no correlation with the disease-free period. All pAgNOR parameters exceeding the respective overall mean had poorer prognosis when compared with those below the mean (P = .02). The pAgNOR > 1 appeared as the best discriminator, singling out all treatment failures (P < or = .001). This parameter also showed a high degree of intraobserver and interobserver reproducibility. Stage of the disease, violated resection margins, and presence of the histopathological solid subtype were markers of an unfavorable prognosis. Multivariate analysis by the Cox model showed that pAgNOR > 1 (P < or = .001) and tumor stage (P = .03) were the only statistically significant parameters. CONCLUSIONS: Estimation of pAgNOR > 1 is easy, quick, and highly reproducible. It may become a useful prognostic parameter in adenoid cystic carcinoma, but larger studies should be performed to confirm the reliability of this method.

Adenoid cystic carcinoma of the esophagus: report of a case.

The case of a 70-year-old Japanese woman with adenoid cystic carcinoma (ACC) of the esophagus is presented herein. The patient presented with progressive dysphagia, and an upper gastrointestinal series and esophagogastroscopy revealed a protruding tumor located in the middle portion of the esophagus. Ultrasonography (US) and computed tomography (CT) suggested a lymph node metastasis between the left lobe of the liver and the esophagocardiac junction. Histopathologic examination of a biopsy specimen showed squamous cell carcinoma (SCC) and a subtotal esophagectomy was performed under the preoperative diagnosis of esophageal carcinoma. However, the histopathologic diagnosis of the resected specimen proved to be ACC of the esophagus with a lymph node metastasis around the left gastric artery. We report the clinicopathological findings of this case and briefly discuss the clinical implications of ACC.

[Study of electron microscopy histochemistry and immunohistochemistry of extracellular matrix in adenoid cystic carcinoma].

In order to determine the character of the extracellular matrix in adenoid cystic carcinoma (ACC), 22 cases of ACC of salivary gland were examined by immunohistochemical methods and 4 cases were examined by electron microscopy histochemically. Immunohistochemistry, type IV collagen and fibronectin were more intensively localized in pseudocyst space and in extracellular matrix between tumor cells. Ultrastructural study showed that the pseudocystic cells had abundant rough endoplasmic reticulum and a well-developed Golgi apparatus, some cells had muscle microfilament. There were laminin, proteoglycan and collagen fibril in the pseudocyst space. The results indicated that type IV collagen and fibronectin were the important stromal component in ACC, which may be secreted by neoplasmic myoepithelial cells.