Alexander Perathoner

Prognostic value of indoleamine 2,3-dioxygenase expression in colorectal cancer: effect on tumor-infiltrating T cells.

PURPOSE: The pathologic interactions between tumor and host immune cells within the tumor microenvironment create an immunosuppressive network that promotes tumor growth and protects the tumor from immune attack. In this study, we examined the contribution of the immunomodulatory enzyme indoleamine 2,3-dioxygenase (IDO) on this phenomenon. EXPERIMENTAL DESIGN: Expression of IDO was analyzed in colorectal cancer cell lines by reverse transcription-PCR and functional enzyme activity was assessed by high-pressure liquid chromatography. Semiquantitative immunohistochemistry was used to evaluate IDO expression in the tissue samples of 143 patients with colorectal carcinoma, and was then correlated with the number of tumor-infiltrating T cells and clinical variables. RESULTS: In vitro IDO expression and functional enzyme activity in colorectal cancer cells was found to be strictly dependent on IFN-gamma stimulation. Immunohistochemical scores revealed IDO-high expression in 56 of 143 (39.2%) tumor specimens, whereas 87 of 143 (60.8%) cases showed low IDO expression levels. IDO-high expression was associated with a significant reduction of CD3+ infiltrating T cells (46.02 +/- 7.25) as compared with tissue samples expressing low IDO (19.42 +/- 2.50; P = 0.0003). Furthermore, IDO-high immunoreactivity significantly correlated with the frequency of liver metastases (P = 0.003). Kaplan-Meier analysis showed the crossing of survival curves at 45 months. By multivariate Coxs analysis, IDO-high expression emerged as an independent prognostic variable (<45 months, P = 0.006; >45 months, P = 0.04). CONCLUSION: IDO-high expression by colorectal tumor cells enables certain cancer subsets to initially avoid immune attack and defeat the invasion of T cells via local tryptophan depletion and the production of proapoptotic tryptophan catabolites. Thus, IDO significantly contributes to disease progression and overall survival in patients with colorectal cancer.

14-3-3σ Expression Is an Independent Prognostic Parameter for Poor Survival in Colorectal Carcinoma Patients

Purpose: 14-3-3σ is an intracellular, dimeric, phosphoserine binding protein that is expressed in epithelial cells and involved in cancer development. In this study, we examined the expression of 14-3-3σ and evaluated its clinical significance in colorectal carcinoma. Experimental Design: Expression of 14-3-3σ was analyzed by Western blot in nine colorectal carcinoma cell lines, eight paired colorectal carcinoma tissues, and normal mucosas. Immunohistochemistry was used to evaluate expression of 14-3-3σ in tissues of 121 colorectal carcinoma patients and to correlate it with clinical parameters. Results: Western blot analysis of colorectal carcinoma cell lines and tissues revealed strong 14-3-3σ expression in four of eight cell lines and 14-3-3σ overexpression in carcinomas compared with normal mucosa in six of eight colorectal carcinoma tissue pairs. Immunohistochemical analysis revealed 14-3-3σ overexpression in 38.8% of colorectal carcinoma samples. Furthermore, highly positive immunoreactivity was significantly correlated with tumor differentiation (P < 0.001) and pT stage (P < 0.003). In Kaplan-Meier analysis, 14-3-3σ overexpression was associated with a significantly decreased survival time compared with negatively stained or low stained cases (P < 0.0096). In multivariate regression analysis, 14-3-3σ expression emerged as a significant independent parameter (P < 0.037). Conclusions: These results provide evidence that 14-3-3σ expression increases during carcinoma progression in a subset of colorectal carcinoma. The overexpression of this antigen identifies patients at high risk. It is tempting to suggest that 14-3-3σ overexpression either promotes tumor proliferation and/or prevents apoptotic signal transduction in colorectal carcinoma. Thus, targeting 14-3-3σ might be a new therapeutic strategy in colorectal carcinoma.

Up-Regulation of Functional Chemokine Receptor CCR3 in Human Renal Cell Carcinoma

There is increasing evidence that chemokines and chemokine receptors are causally involved in tumorigenesis by facilitating tumor proliferation and metastasis. Little is known about the possible function of chemokine receptors in the development and progression of renal cell carcinoma (RCC). We, therefore, analyzed the expression of chemokine receptors in tumor specimens and adjacent healthy kidney tissues [normal kidney cell (NKC)] from 10 RCC patients. We also characterized the permanent RCC cell line A-498. CCR6, CXCR2, and CXCR3 were consistently expressed by both malignant cells and NKCs. A-498 displayed additional expression of CXCR4. Importantly, the expression of CCR3 was almost absent on NKCs but clearly enhanced in a substantial proportion of RCC specimens. The primary CCR3 ligand, eotaxin-1/CCL11, induced intracellular Ca2+ mobilization, receptor internalization, and proliferation in A-498 cells confirming signaling competence of RCC-associated CCR3. In addition, we screened tumor tissue sections of 219 patients and found that 28% (62 of 219) expressed the CCR3 receptor. The presence of CCR3 in tumor samples seemed to correlate with the grade of malignancy. Previous work has established that eotaxin-1 expression is induced by tumor necrosis factor-α, a cytokine known to be present in RCC tissue. Our data, therefore, supports a scenario in which eotaxin-1 as part of tumor-associated inflammation promotes progression and dissemination of CCR3-positive RCC.

Dickkopf-3 As a New Potential Marker for Neoangiogenesis in Colorectal Cancer: Expression in Cancer Tissue and Adjacent Non-Cancerous Tissue

Gene expression of Dickkopf-3 (Dkk-3) has been shown to be upregulated in tumor endothelium of colorectal cancer (CRC). For the first time, we analyzed Dkk-3 protein expression in CRC and its potential as a marker for neoangiogenesis. We used tissue microarrays (TMAs) to investigate Dkk-3 in microvessels of 403 CRC samples, 318 appropriate adjacent non-cancerous samples and 127 normal colorectal samples. Of cancer samples with CD31-positive microvessels, 67.7% were positive for Dkk-3. Dkk-3 staining was demonstrated in endothelial cells of all microvessels in nearly all cases. Dkk-3-positive samples showed a higher mean microvessel count than did Dkk-3-negative samples (P=0.001). Dkk-3 expression increased with rising numbers of microvessels per sample (P<0.0001). In adjacent samples with CD31-positive microvessels, 56% were Dkk-3-positive in all microvessels. Similar to cancer samples, Dkk-3-positive adjacent samples had a higher mean microvessel count than did Dkk-3-negative samples (P<0.0001), and Dkk-3 expression also increased with rising numbers of microvessels (P<0.0001). All microvessels in normal mucosa samples were negative for Dkk-3. Dkk-3 can be considered a putative pro-angiogenic protein in neovascularization and may possibly be a marker for neoangiogenesis in CRC. Further investigations will elucidate whether Dkk-3 is a target structure for novel therapies.

Expression and prognostic impact of indoleamine 2,3-dioxygenase in oral squamous cell carcinomas.

Indoleamine 2,3 dioxygenase (IDO) is a negative immune regulator and was found to be a prognostic marker in several tumor entities. In this study, we analysed IDO expression in oral squamous cell carcinoma (OSCC) regarding patients prognosis. Additionally, expression of IDO like-1 gene (INDOL-1) was analysed. Tumor tissue from 88 patients with OSCC was analysed by immunohistochemistry for IDO expression. The influence of IDO expression on survival was studied by multivariate Cox regression, adjusting for established clinical prognostic parameters. Real time PCR of tumor samples was performed in a subgroup of patients to analyse mRNA expression of IDO and INDOL-1. IDO high-expression was observed in 44.2% of OSCC patients. No significant correlation was found between IDO expression and clinical stage, sex, age, tumor site, tumor size, metastasis or tumor grade. The median overall survival time was 3.1 years for patients with IDO low tumors, compared to 1.36 years for IDO high tumors (P=.028). Subset analysis of patients receiving adjuvant radio-chemotherapy showed a significant difference (P=.0046) in overall survival between IDO low tumors (3.35 years) and IDO high tumors (1.26 years). In contrast, the impact of IDO expression on survival time in patients without adjuvant therapy was not significant (P=.574). Interestingly, INDOL-1 was not expressed in OSCC. IDO high expression represents a significant negative prognostic factor in patients with OSCC, especially in those patients undergoing adjuvant radiochemotherapy. Our data support the suggestion, co-administration of small-molecule IDO inhibitors could represent a promising new strategy to increase the anti-tumor activity of radio-chemotherapy in patients with IDO positive OSCC.

Routine upper gastrointestinal swallow studies after laparoscopic sleeve gastrectomy are unnecessary.

BACKGROUND Laparoscopic sleeve gastrectomy has gained popularity among bariatric surgeons. The purpose of this study was to evaluate the usefulness of early upper gastrointestinal (UGI) contrast studies in the detection of postoperative complications. METHODS Radiographic reports were reviewed from April 2006 to January 2013. During that time, 161 patients underwent laparoscopic sleeve gastrectomy. All patients were submitted to UGI examination on postoperative day (POD) 1. RESULTS Among the 161 patients who underwent UGI, no contrast leaks were found on POD 1. Three patients (1.9%) developed stapler line leaks near the gastroesophageal junction, which were diagnosed on PODs 3, 4, and 10. Gastroesophageal reflux in 5 patients (3.1%) and delayed gastroesophageal transit in 10 patients (6.2%) were detected. CONCLUSIONS The results of this study show that UGI series on POD 1 cannot assess the integrity of the gastric remnant. Early UGI series are not required as routine procedures in all operated patients. Computed tomographic swallow studies should be performed in patients who postoperatively develop clinical signs and symptoms of complications such as tachycardia, pain, or fever.

Prognostic significance of 14-3-3σ expression in oral squamous cell carcinoma (OSCC)

14-3-3sigma an intracellular phosphoserine binding protein regulates different cellular signalling processes and is involved in cancer development. In this study, we examined the expression of 14-3-3sigma and evaluated its clinical significance in OSCC. Tumour tissue from 95 OSCC patients was analysed for 14-3-3sigma and p53 expression, respectively. The correlation of these proteins with survival and clinical parameters was assessed. 14-3-3sigma high expression was observed in 44.2% of OSCC patients. A significant role of 14-3-3sigma expression on survival was shown by Kaplan-Meier analysis. Median survival time was 4.1years for patients with 14-3-3sigma low tumours, compared with 1.36years for 14-3-3sigma high tumours (P=.0021). Subset analysis in patients receiving adjuvant chemotherapy showed that the overall survival was significantly decreased in 14-3-3sigma high tumours than in 14-3-3sigma low tumours (P=.02). p53 expression was not significant in univariate analyses. In multivariate regression analysis, 14-3-3sigma expression emerged as a significant independent parameter (P=.003). These results provide evidence that 14-3-3sigma expression is involved in OSCC and, in contrast to p53 expression represents a new prognostic marker for OSCC and therapy response. Pending validation targeting 14-3-3sigma might also be a new opportunity to improve therapy.

Enterolithiasis-associated ileus in Crohn's disease.

Stasis of the flow of the intestinal contents, ingested material and unfavorable composition of the chylus can lead to the formation of enteroliths inside the bowel. Enterolithiasis represents a rare disorder of the gastrointestinal tract that can be associated with intermittent abdominal pain or more serious complications such as bleeding or obstruction. Enterolithiasis in Crohns disease represents an extremely rare condition and usually occurs only in patients with a long symptomatic history of Crohns disease. We report an unusual case of enterolithiasis-related intestinal obstruction in a young male patient with Crohns disease (A2L3B1 Montreal Classification for Crohns disease 2005) undergoing emergency laparotomy and ileocoecal resection. In addition, we present an overview of the relevant characteristics of enterolithiasis on the basis of the corresponding literature.

Letter to the Editor: Surgical Treatment of the Open Abdomen in Patients with Abdominal Sepsis Using the Vacuum Assisted Closure System

We read with great interest the article by Wondberg et al. titled ‘‘Treatment of the open abdomen with the commercially available vacuum-assisted closure system in patients with abdominal sepsis’’ [1] in the December 2008 issue of World Journal of Surgery. In recent years the application of negative intra-abdominal pressure has become a promising treatment strategy in critically ill patients with abdominal compartment syndrome, open abdomen, or even severe abdominal septic complications [2–4]. Because to date only a few studies on intra-abdominal vacuum-assisted closure (VAC) therapy in patients with abdominal sepsis have been published, the article by Wondberg et al. seems to be especially important. However, the low rate of fascial closure reported in this study was somewhat surprising and led us to conclude that the VAC system may have been applied too late or too long. In addition, some important considerations regarding the use of the VAC system were not mentioned in the article: First, the authors did not state the time interval between first surgery (scheduled surgery with postoperative complications versus emergency surgery) and application of the VAC system, nor did they indicate the number of operations performed before the application of the negative pressure therapy. Second, the absolute duration of VAC therapy was unclear, and the authors did not differentiate between intra-abdominal and subcutaneous use of the VAC system. In our opinion, these facts represent crucial elements for evaluation of the effect of the VAC system in abdominal surgery, because the extent of fascial retraction and the rate of fascial closure depend in large part on the time of first application and the duration of VAC therapy. In fact, we have observed that VAC therapy alone can prevent fascial retraction only for a few days, because continual muscular tension of the abdominal wall apparently exceeds the effect of the maximal negative pressure of the VAC system. We therefore believe, that the stability of the abdominal wall in patients with prolonged VAC therapy can be sustained only by additional measures. Thus, since 2004 we have used three or four interrupted dynamical sutures with elastic vessel loops (a measure proposed by T. Wild, Medical University, Vienna, Austria) to achieve and maintain approximation of the fascial margins in every patient treated with abdominal VAC therapy. With this technique, the effect of the negative pressure therapy is not impaired at all, and a complete fascial closure is feasible in the majority of patients with abdominal sepsis after several days. In view of the low VAC-associated morbidity in the study by Wondberg et al., we want to affirm the increasing importance of the VAC system in the management of critically ill patients with septic abdomen, because it allows rapid control of peritonitis and an easy return to the abdominal cavity. However, further studies and randomized controlled trials are necessary to define the optimal use of the VAC system in septic abdominal surgery.

Surgical aspects in the treatment of retroperitoneal soft tissue sarcomas

Abdominal soft tissue sarcomas (ASTS) represent a rare malignancy of the abdomen. Diagnosis is often delayed because ASTS tend to be asymptomatic for a long time. Typical clinical symptoms such as pain and augmentation of the abdominal girth develop as a result of the compressing and displacing rather than infiltrating growth pattern of large ASTS. Treatment of patients with ASTS should be managed interdisciplinarily in a tumourboard. Surgery (i.e. wide excision with negative margins) represents the only potentially curative treatment option. Multimodal treatment with radiotherapy and/or chemotherapy, however, is indispensable to reduce the rather high local recurrence rate in these patients despite complete resection. A preoperative core needle biopsy is recommended if diagnosis and hence also therapy are unclear: the biopsy pathway should be chosen in accordance with the surgeon, and the excision has to be performed afterwards within primary surgery. The aggressiveness of surgery is still under debate and ranges from a tissue/organ-sparing approach to an extensive approach with compartmental resection. Thus, the oncologic surgeon must be able to handle complex multivisceral resection as well as extensive vascular reconstruction. Surgery for local recurrence has been shown to be feasible, and the presence of distant metastases usually represents a contraindication for surgery.