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Comprehensive molecular analyses revealed that papillary renal cell carcinoma (PRCC) is a heterogenous entity. Papillary renal neoplasm with reverse polarity (PRNRP) is a subset of PRCC with characteristic histomorphologies such as low-grade nuclear features, inverted nuclear location, eosinophilic cytoplasm, and indolent clinical behavior. We tried to define the molecular, clinicopathological, histologic, and immunohistochemical features of PRNRP by comparing them with type 1 PRCC (PRCC1) and type 2 PRCC (PRCC2). A cohort of 30 PRNRP, 23 PRCC1, and 26 PRCC2 cases was used. Targeted sequencing of 90 cancer-related genes including KRAS was performed in 26 PRNRP tumor samples. PNA-mediated clamping PCR of KRAS was performed using paired normal and tumor DNA from 30 PRNRP, 23 PRCC1, and 26 PRCC2 cases. Tissue microarray slides were made in three cores per tumor, which were stained with cytokeratin 7 (CK7), alpha-methylacyl-CoA racemase (AMACR), epithelial membrane antigen (EMA), E-cadherin, vimentin, and CD10. Recurrent mutations in KRAS were detected in 28 of the 30 PRNRPs. However, there were no KRAS mutations in any PRCC1 or PRCC2 cases. PRNRP exhibited distinct clinicopathological features: small tumor size, lower pathologic T stage, and no disease-specific death during the follow-up period. Histologically, peritumoral lymphoid aggregation, prominent papillary architecture (>80% of tumor), hyalinized papillae, inverted nuclear location, and lower nuclear grade were observed. PRNRP was usually positive for CK7, AMACR, EMA, and E-cadherin, and negative for CD10. The findings suggest that PRNRP is a subtype of papillary renal neoplasm that is different from PRCC1 or PRCC2 in terms of molecular, clinicopathological, histological, and immunohistochemical features.

Andrographolide, a natural compound isolated from Andrographis paniculata, has been reported to possess antitumor activity. In the present study, the effect of andrographolide in human gastric cancer (GC) cells was investigated. Andrographolide induced cell death with apoptotic and non-apoptotic features. At a low concentration, andrographolide potentiated apoptosis and reduction of clonogenicity triggered by recombinant human tumor necrosis factor-related apoptosis-inducing ligand (rhTRAIL). Exposure of GC cells to andrographolide altered the expression level of several growth-inhibiting and apoptosis-regulating proteins, including death receptors. It was demonstrated that activity of the TRAIL-R2 (DR5) pathway was critical in the development of andrographolide-mediated rhTRAIL sensitization, since its inhibition significantly reduced the extent of apoptosis induced by the combination of rhTRAIL and andrographolide. In addition, andrographolide increased reactive oxygen species (ROS) generation in a dose-dependent manner. N-acetyl cysteine prevented andrographolide-mediated DR5 induction and the apoptotic effect induced by the combination of rhTRAIL and andrographolide. Collectively, the present study demonstrated that andrographolide enhances TRAIL-induced apoptosis through induction of DR5 expression. This effect appears to involve ROS generation in GCs.

Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anticancer agent, a number of cancer cells demonstrate TRAIL resistance. To date, various molecular targets leading to TRAIL resistance have been elucidated by many researchers, but the mechanisms involved are still not fully understood. In the present study, we obtained TRAIL-resistant cells from the human hepatocellular carcinoma cell line HepG2 by exposing cells to recombinant human TRAIL (rhTRAIL), and determined a mechanism for TRAIL resistance. The selected TRAIL-resistant cells (HepG2-TR) were insensitive to rhTRAIL and triggered autophagy in response to rhTRAIL. The inhibition of autophagy by 3-methyladenine or the knockdown of ATG5 partially restored rhTRAIL-induced apoptosis and cytotoxicity, indicating that protective autophagy occurred in the cells. Notably, rhTRAIL-induced autophagy was mediated through DR4 in HepG2-TR cells, but not in parental HepG2 cells. In addition, the c-Jun N-terminal kinase was involved in DR4-mediated autophagy in HepG2-TR cells. Our results suggest a novel mechanism of TRAIL resistance which is regulated through alterations in DR4 function, which may extend our understanding of the mechanisms of TRAIL resistance.

Capsaicin, a pungent compound found in hot chili peppers, induces apoptotic cell death in various cell lines, however, the precise apoptosis signaling pathway is unknown. Here, we investigated capsaicin-induced apoptotic signaling in the human breast cell line MCF10A and found that it involves both endoplasmic reticulum (ER) stress and calpain activation. Capsaicin inhibited growth in a dose-dependent manner and induced apoptotic nuclear changes in MCF10A cells. Capsaicin also induced degradation of tumor suppressor p53; this effect was enhanced by the ER stressor tunicamycin. The proteasome inhibitor MG132 completely blocked capsaicin-induced p53 degradation and enhanced apoptotic cell death. Capsaicin treatment triggered ER stress by increasing levels of IRE1, GADD153/Chop, GRP78/Bip, and activated caspase-4. It led to an increase in cytosolic Ca(2+), calpain activation, loss of the mitochondrial transmembrane potential, release of mitochondrial cytochrome c, and caspase-9 and -7 activation. Furthermore, capsaicin-induced the mitochondrial apoptotic pathway through calpain-mediated Bid translocation to the mitochondria and nuclear translocation of apoptosis-inducing factor (AIF). Capsaicin-induced caspase-9, Bid cleavage, and AIF translocation were blocked by calpeptin, and BAPTA and calpeptin attenuated calpain activation and Bid cleavage. Thus, both ER stress- and mitochondria-mediated death pathways are involved in capsaicin-induced apoptosis.

We analyzed six cystectomized specimens diagnosed as transitional cell carcinoma by immunohistochemical evaluation to determine the presence of c-erbB2, transforming growth factor-alpha (TGF-alpha), c-myc, c-fos, and c-fms. Representative sections of flat lesions with atypia (e.g., reactive atypia, dysplasia, and carcinoma in situ) and invasive neoplasms (transitional cell carcinoma, TCC) were selected for each cystectomy specimen according to the new WHO/ISUP classification. The average percentage of cells found positive for c-erbB2 were 16.3%, 45.5%, 46.1% and 67.7% in the reactive atypia, dysplasia, carcinoma in situ, and invasive TCC, respectively. The average percentage of cells found positive for TGF-alpha were 9.7%, 13.3%, 13.5%, 30.3%, respectively. The cells were negative for the oncoproteins c-myc and c-fos. The average percentage of cells found positive for the oncoprotein c-fms was 10.6%, 15.5%, 16.7%, and 45.5% respectively. The results of this study indicated that various oncoproteins are expressed differently. c-erbB2, TGF-alpha and c-fms expression was gradually increased during tumorous progression of the urothelium from reactive atypia to invasive carcinoma. The presence of c-erbB2, TGF-alpha and c-fms is an important marker for detection of an early precursor lesions of invasive carcinoma. However, c-myc and c-fos were not expressed in the urothelial reactive atypia and dysplasia and did not correlate with tumor progression.

Malignant mixed mullerian tumors (MMMT) are unusual neoplasms occurring mostly in the uterus. In the ovary, they are very rare and represent fewer than 1% of all ovarian malignancies; in the salpinx, they are even rarer than those of the ovary. We report a carcinosarcoma of the left adnexa having features of neuroendocrine differentiation in a 69-year-old female. The tumor contained both adenocarcinoma and squamous cell carcinoma having dear cell change admixed with an undifferentiated malignant mesenchymal component. The sarcoma components consisted of spindle cells, small-round cells and bizarre giant cells mimicking rhabdomyoblast. Almost all of the carcinomatous glandular components and some foci of the squamous cell and undifferentiated carcinomatous components were focal positive for S-100 protein, chromogranin, neuron specific enolase, synaptophysin and Leu-7. Electron microscopy revealed membrane-bound neurosecretory granules in the cytoplasm of some glandular epithelial cells. Histologically, the tumor involved the left adnexa, abdominal peritoneum, surface of the bladder dome, omentum and left external iliac lymph node (stage IIIc).

Mantle cell lymphoma, blastoid variant (B-MCL), is a very rare type of non-Hodgkin's lymphoma exhibiting an aggressive clinical course. We describe a case of B-MCL showing generalized lymphadenopathy and leukemic conversion in a 62-yr-old man. The case was diagnosed and subclassified as B-MCL on the basis of cyto-morphology and immunophenotype. Microscopic examination of the peripheral blood (PB) showed a spectrum of cells ranging from small mature lymphocytes to medium- and large-sized lymphocytes with blast-like chromatin and prominent nucleoli. The lymphoma cells were monoclonal B cells with moderately intense surface IgM. They were CD5 positive, cyclin D1 positive, CD10 negative, and CD23 negative. The flow cytometric immunophenotyping and DNA ploidy analysis of the PB and material obtained by aspiration cytology supported the diagnosis of B-MCL. These findings underline the utility of aspiration cytology in diagnosing B-MCL when cytomorphologic examination is combined with flow cytometric analysis of immuno-phenotype and demonstration of proliferation markers.