Biological evaluation of undifferentiated carcinoma of the esophagus

Surgical Resection of Rare Esophageal Cancers

BACKGROUND

Although surgical resection of adenocarcinoma or squamous cell carcinoma of the esophagus is standard practice, the treatment strategy for other malignant rare esophageal cancers is still under debate. The aim of this study was to examine the treatment of rare malignant esophageal cancers and to evaluate the survival of these patients.

METHODS

A retrospective review of all esophagectomies performed at Mayo Clinic from 1980 to 2014 (approximately 4,000 cases) identified 24 patients with histologic features other than adenocarcinoma or squamous cell carcinoma. Their medical records were reviewed for demographics, presenting symptoms, evaluation, surgical management, pathologic features, and short-term and long-term outcome.

RESULTS

Pathologic identifications included small cell carcinoma, lymphoma, and undifferentiated carcinoma in 4 (16.7%) patients each and neuroendocrine, melanoma, leiomyosarcoma, sarcomatoid, sarcoma, and gastrointestinal stromal tumor in 2 (8.3%) patients each. The most common presenting symptoms included dysphasia in 91.7% patients (22/24), pain in 75.0% (18/24), and weight loss in 62.5% (15/24). Preoperative evaluation included barium swallow in 91.7% (22/24), computed tomography in 91.7% (22/24), positron emission tomography in 54.2% (13/24), esophagogastroduodenoscopy in 100% (24/24), and endoscopic ultrasonography in 29.2% (7/24) patients. The location of the tumor was at the gastroesophageal junction in 41.7% (10/24). There was no operative mortality, and 13 patients (54.16%) had at least one postoperative adverse event. The 1-year survival after esophagectomy was 69.7%, the 5-year survival was 42.7%, and the 10-year survival was 37.4%.

CONCLUSIONS

Esophageal cancer with pathologic features other than squamous cell carcinoma or adenocarcinoma is rare. Esophagectomy for rare types of malignant esophageal cancers should be considered part of the effective treatment paradigm.

Knockdown of thrombomodulin enhances HCC cell migration through increase of ZEB1 and decrease of E-cadherin gene expression

BACKGROUND

Thrombomodulin (TM) is a key molecule mediating circulation homeostasis through its binding to thrombin. The TM-thrombin complex can activate protein C and thrombin-activatable fibrinolysis inhibitor to form a tight clot. In many cancer tissues, decrease of TM expression may correlate with cancer metastasis. However, the role of TM in hepatocellular carcinoma (HCC) progression is still unclear.

METHODS

We characterized TM expression in HCC cells (HepJ5 and skHep-1 cells) using real-time polymerase chain reaction (PCR) and Western blotting. We then manipulated TM expression using both TM-specific short hairpin RNA (shRNA) and overexpressing it in HCC cells. Transwell migration assay was performed to monitor the migratory ability of HCC cells under different levels of TM expression.

RESULTS

We found that TM was ectopically highly expressed in skHep-1 at both transcriptional and translational levels. After silencing TM expression in skHep-1 cells, we found that metastatic capability was dramatically increased. Conversely, overexpression of TM in HepJ5 cells decreased metastatic ability. We investigated the possible mechanism and found that decreased TM-mediated enhancement of cell migration was dependent on upregulation of ZEB1, a repressor of E-cadherin.

CONCLUSIONS

TM may be a modulator of cancer metastasis in HCC. Downregulation of TM expression may increase ZEB1 and decrease E-cadherin levels.

Expressão imunohistoquímica de P53 e Ki-67 na carcinogênese esofágica induzida pela dietilnitrosamina: modelo experimental

OBJETIVO: Avaliar a expressão imunohistoquímica de p53 e ki-67 na carcinogênese esofágica induzida quimicamente através do uso de dietilnitrosamina, em um grupo de 100 camundongos fêmeas. MÉTODOS: O estudo experimental foi realizado com quatro grupos de animais, onde os grupos I e II foram considerados controles, sendo diferenciados por gavagem esofágica, uma vez semana, com água fria (temperatura ambiente) ou quente (60º-70ºC). E os grupos III e IV foram considerados estudos, os quais receberam dietilnitrosamina por três dias consecutivos semanalmente, também sendo diferenciados por gavagem, uma vez por semana, com água fria ou quente. O estudo apresentou datas progressivas de sacrifícios com coleta de peças esofágicas, que iniciava aos 30 dias de experimento e terminava aos 150 dias. Demonstrou-se que não houve diferença na incidência tumoral quando foi acrescida a variável temperatura da água; provavelmente devido ao episódio único semanal que era adicionado ao animal em experimentação. RESULTADOS: A análise imunohistoquímica do p53 não evidenciou diferença estatística durante a evolução da carcinogênese até 150 dias, porém quando analisado a relação com alterações patológicas demonstra-se que apresenta significância em relação à patologia baixo grau de displasia, alto grau e carcinoma. CONCLUSÃO: A análise imunohistoquímica do ki-67 demonstrou diferença estatística durante a evolução da carcinogênese a partir do dia 120 de experimento e quando analisada a relação com alterações patológicas demonstrou-se que apresenta significância também em relação à lesão intraepitelial de alto grau e carcinoma.

Increased expression of Dsg2 in malignant skin carcinomas: A tissue-microarray based study

Desmoglein 2 (Dsg2), a transmembrane cadherin of the desmosomal cell-cell adhesion structure, is downregulated with epithelial differentiation. We recently demonstrated that overexpression of Dsg2 in epidermal keratinocytes deregulates multiple signaling pathways associated with increased growth rate, anchorage-independent cell survival, and the development of skin tumors. While changes in Dsg2 expression have been observed in neoplastic lesions, the correlation of expression levels and localization of Dsg2 and the state of tumor development has not been fully established. Here we generated a highly sensitive Dsg2 antibody (Ab10) and characterized that antibody along with a previously developed Dsg2 specific antibody 10D2. Using these antibodies in immunostaining of tissue microarrays, we show a dramatic upregulation of Dsg2 expression in certain human epithelial malignancies including basal cell carcinomas (BCC; n = 12), squamous cell carcinomas (SCC; n = 57), carcinomas of sebaceous and sweat glands (n = 12), and adenocarcinomas (n = 3). Dsg2 expression was completely absent in malignant fibrosarcomas (n = 16) and melanomas (n = 15). While Dsg2 expression was consistently strong in BCC, it varied in SCC with a minor correlation between a decrease of Dsg2 expression and tumor differentiation. In summary, we have identified Dsg2 as a potential novel marker for epithelial-derived malignancies.

Thrombomodulin enhances the invasive activity of mouse mammary tumor cells

Thrombomodulin (TM) is a thrombin receptor on the surface of endothelial cells that converts thrombin from a procoagulant to an anticoagulant. Thrombin promotes invasion by various tumor cells, and positive or negative correlations are found between the expression of TM and tumorigenesis in some patients. In this study, we used an invasion assay to investigate the effect of TM on the invasive activity of a mouse mammary tumor cell line, MMT cells, and the effects of TM were compared with those of thrombin as a positive control. In the presence of 1% fetal calf serum (FCS), TM significantly stimulated MMT cell invasion in a dose-dependent manner, resulting in an approximately 3-fold increase at 1-10 pg/ml over the untreated control. Thrombin also caused a similar degree of stimulation at 50 ng/ml. Since thrombin activity was detected in the components of the assay system, an invasion assay was also performed in a thrombin-activity-depleted assay system constructed to eliminate the effect of thrombin activity; TM (10 pg/ml) plus thrombin (1 pg/ml) stimulated invasion by approximately 3.5-fold in this assay system. Hirudin, a specific thrombin inhibitor, inhibited stimulation by TM as well as by thrombin in both the presence and absence of 1% FCS. Investigations of the effects of TM on proliferation, adhesion and chemotaxis to clarify the mechanism of stimulation by TM revealed that TM does not affect proliferation or adhesion in the presence of 1% FCS, but stimulates chemotaxis by approximately 2.3-fold. Similar results were obtained in experiments using thrombin. TM (10 pg/ml) plus thrombin (1 pg/ml), on the other hand, stimulated chemotaxis by approximately 2.3-fold in the thrombin-activity-depleted assay system. Binding studies using [125I]-thrombin revealed that the cells have specific saturable binding sites for thrombin. These results show that TM stimulates the invasive activity of MMT cells, probably by acting as a cofactor for the thrombin-stimulated invasion of the cells via its receptor and lowering the effective concentration of thrombin. The findings also indicate that the stimulation of invasive activity in the presence of 1% FCS and in the thrombin-activity-depleted assay system may mainly be mediated by the stimulation of chemotaxis.

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Surgery, radiotherapy, and chemotherapy for esophageal carcinoma

Over the last year, several interesting studies have been published on the treatment of esophageal carcinoma. Surprisingly, none of them was a randomized phase III trial. The debate on the necessary extent of a potentially curative surgical resection is ongoing. After initially disappointing results, the innovative technique of minimally invasive surgery draws new attention, but clear advantages for the endoscopic approach are yet to emerge. An updated meta-analysis on the value of preoperative radiotherapy showed negative results. There is a clear tendency toward combined-modality treatment, especially in patients with more advanced disease. Some new chemotherapeutic agents showed promising preliminary results (especially paclitaxel), whereas others were clearly disappointing (eg, gemcitabine, topotecan). Concurrent chemoradiation as primary treatment for proximal (cervical) tumors was remarkably effective.