No inflammatory benefit obtained by single-incision laparoscopic surgery for right hemicolectomy compared with conventional laparoscopy.

PURPOSE: We evaluated the perioperative inflammatory mediators in a right hemicolectomy performed with single-incision laparoscopic surgery (SILS) and traditional multi-port laparoscopic surgery (MLS) to compare the postoperative inflammatory response and feasibility of SILS with that of MLS. METHODS: In this retrospective study, we enrolled 56 consecutive colorectal cancer patients who underwent right hemicolectomy prospectively. Twenty patients underwent SILS, and 36 underwent MLS. The preoperative and postoperative levels of plasma vascular endothelial growth factor (VEGF), serum interleukin-6 (IL-6), and C-reactive protein (CRP) as well as the number of platelet cells were measured in all patients. The operation duration, number of harvested lymph nodes, length of the resected bowel, blood loss, and duration of hospital stay were also compared between the two groups. RESULTS: Neither SILS nor MLS had any conversion cases. The operation duration was longer for MLS than for SILS. Blood loss tended to be lower among patients who underwent SILS than among those who underwent MLS. However, the number of harvested LNs was significantly lower with SILS than with MLS. In both pre- and postoperative blood examinations, there was no marked difference in inflammatory mediators between MLS and SILS. CONCLUSION: There was no systemic inflammatory advantage associated with SILS compared with MLS.

[Radiotherapy for Bone Metastasis after Esophageal Cancer Surgery].

We examined the usefulness of radiotherapy for bone metastasis after esophageal cancer surgery. Between 2001 and 2016, we performed surgical resection for esophageal cancer in our department and 11 patients had postoperative bone metastases. Of these, 7 underwent radiotherapy. The median age was 71(60 to 76)years, with 5 males and 2 females. Six cases were squamous cell carcinoma and 1 case was adenocarcinoma. Metastatic sites included 3 vertebral bodies, 2 ribs, 2 skull bones, 1 ilium, 2 humerus, and 1 femur(there was overlap). Six cases also had other distant metastases. Three cases also underwent chemotherapy. Four of 7 cases(57%)showed reduction of metastatic lesions. The pain improvement rate was 57%. Radiation therapy for bone metastasis in esophageal cancer is thought to be effective for reduction of metastatic lesions and pain relief.

Xanthohumol inhibits angiogenesis by suppressing nuclear factor-κB activation in pancreatic cancer.

Xantohumol, a prenylated chalcone from hops (Humulus lupulus L.), has been shown to inhibit proliferation in some cancers. However, little is known regarding the effects of xanthohumol in pancreatic cancer. We have previously reported that activation of the transcription factor nuclear factor-κB (NF-κB) plays a key role in angiogenesis in pancreatic cancer. In this study, we investigated whether xanthohumol inhibited angiogenesis by blocking NF-κB activation in pancreatic cancer in vitro and in vivo. We initially confirmed that xanthohumol significantly inhibited proliferation and NF-κB activation in pancreatic cancer cell lines. Next, we demonstrated that xanthohumol significantly suppressed the expression of vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) at both the mRNA and protein levels in pancreatic cancer cell lines. We also found that coculture with BxPC-3 cells significantly enhanced tube formation in human umbilical vein endothelial cells, and treatment with xanthohumol significantly blocked this effect. In vivo, the volume of BxPC-3 subcutaneous xenograft tumors was significantly reduced in mice treated with weekly intraperitoneal injections of xanthohumol. Immunohistochemistry revealed that xanthohumol inhibited Ki-67 expression, CD31-positive microvessel density, NF-κB p65 expression, and VEGF and IL-8 levels. Taken together, these results showed, for the first time, that xanthohumol inhibited angiogenesis by suppressing NF-κB activity in pancreatic cancer. Accordingly, xanthohumol may represent a novel therapeutic agent for the management of pancreatic cancer.

[A Methotrexate-Associated Malignant Lymphoma with Laparoscopic Resection of the Pericardium].

We report a case of a malignant lymphoma that was treated with laparoscopic resection of the pericardium. A 43-year-old woman was diagnosed with asymptomatic extrahepatic nodule by medical examination. CT, MRI, and PET-CT examination indicated a solitary fibrous tumor(SFT). Therefore, we performed laparoscopic resection for definitive diagnosis and treatment. The tumor was located in the upper abdominal wall and adhered to the liver; hence, we additionally performed partial resection of the liver. Thereafter, we dissected the tumor from the abdominal wall alongwith a part of the diaphragm. Because intraoperative pathological examination revealed more malignancy than was preoperatively expected, we also resected a part of the pericardium. The laparoscopic approach to the pericardium can be performed safely because of its magnification effect, which is an advantage of laparoscopic surgery.

Nuclear expression of TCF4/TCF7L2 is correlated with poor prognosis in patients with esophageal squamous cell carcinoma.

The prognosis for patients with esophageal cancer remains poor. Therefore, the identification of novel target molecules for the treatment of esophageal cancer is necessary. Here, we investigated the clinicopathological significance of transcription factor 4/transcription factor 7-like 2 (TCF4/TCF7L2) in resectable esophageal squamous cell carcinoma (ESCC), because TCF4/TCF7L2 expression has not been studied in esophageal cancer previously. This study included 79 patients with esophageal cancer who underwent surgery between 1998 and 2005. The expression of the TCF4/TCF7L2 protein in the nucleus of esophageal cancer cells was analyzed using immunohistochemistry. We examined the correlation between TCF4/TCF7L2 expression, clinicopathological factors, and prognosis in patients with ESCC. TCF4/TCF7L2 was expressed in 57 % (45/79) of patients. TCF4/TCF7L2 expression was correlated with T factor (T1 vs. T2-4, p = 0.001), stage (I vs. II-IV, p =0.0058), Ly factor (p =0.038), and V factor (p =0.038) and did not correlate with age, gender or N factor. Furthermore, patients who were positive for TCF4/TCF7L2 had a significantly lower survival rate than those who were negative for TCF4/TCF7L2 (log-rank test, p = 0.0040). TCF4/TCF7L2 expression significantly affected the survival of patients with ESCC. Positive expression of TCF4/TCF7L2 was correlated with a poor prognosis after a curative operation in patients with ESCC.

Decreased expression of CDH1 or CTNNB1 affects poor prognosis of patients with esophageal cancer.

BACKGROUND: E-cadherin/CDH1 is one of the proteins involved in cell adhesion, and it is known that decreased expression of E-cadherin induces lymph node metastasis in esophageal cancer. Beta catenin/CTNNB1, which is an important component of the Wnt signaling pathway, binds to E-cadherin at the cell membrane, where the complex of these two proteins functions in the stabilization of cell adhesion. However, its role in the pathogenesis of esophageal cancer is still unknown. METHODS: This study included 86 patients with esophageal cancer who underwent surgery between 1998 and 2007. The expression of the E-cadherin/CDH1 gene product (E-cadherin/CDH1) and that of the beta catenin/CTNNB1 protein in the cell membrane were analyzed by immunohistochemistry. We examined the correlations among CDH1 or CTNNB1 expression, clinicopathological factors, and the prognosis of patients with ESCC. RESULTS: CDH1 and CTNNB1 were expressed in 52.3 % (45/86) and 36.0 % (31/86) of tumor samples, respectively. Both CDH1 and CTNNB1 were co-expressed in 22.1 % (19/86) of esophageal cancer tissues. CDH1 expression correlated with the p-stage (stages I-II vs stages III-IV, p = 0.032), T factor (T1-2 vs T3-4, p = 0.0088), and lymphatic invasion (p = 0.019). However, CDH1 expression did not correlate with the N factor or the blood vessel invasion. CTNNB1 expression correlated with the T factor (T1-2 vs T3-4, p = 0.0015), p-stage (stages I-II vs stages III-IV, p = 0.030), and lymphatic invasion (p = 0.007). The CDH1(+)/CTNNB1(+) phenotype was inversely correlated with the T factor, N factor, p-stage, lymphatic invasion, and blood vessel invasion. Furthermore, patients whose tumors were double-positive for CDH1 and CTNNB1 had a significantly higher survival rate than those whose tumors were negative for CDH1 or CTNNB1 (log-rank test, p = 0.0192). The T factor and N factor had a strong negative correlation with double-positive tumors. These were both independent prognostic factors, as was the double-positive phenotype. A univariate analysis indicated that the T factor, the N factor, and CDH1 and CTNNB1 co-expression were significant variables that predicted survival (hazard ratio, 2.387; 95 % confidence interval, 1.115-5.102; p = 0.025). CONCLUSIONS: Decreased expression of CDH1 or CTNNB1 in the cell membranes of cancer cells is associated with poor survival of patients with esophageal cancer.

Bypass Operation as Palliation for Unresectable Esophageal Cancer: Selection of Suitable Patients.

We evaluated the bypass operation as palliation for unresectable esophageal cancer. In this study, patients were divided into 2 groups. Group A included 19 patients with good progress, defined as sufficient oral ingestion for more than 2 months. The other 10 patients were in Group B and had poor progress. Oral ingestion was impossible postoperatively in 2 of 29 cases. Although there is a difference of a grade, other patients could have improvement of quality of life. Patients with no preoperative therapy and patients whose nutrient state was maintained comparatively well had a good adaptation after bypass surgery. We concluded that if the surgeon chooses the patients carefully, bypass is a very useful operative method.

Simultaneous knock-down of Bcl-xL and Mcl-1 induces apoptosis through Bax activation in pancreatic cancer cells.

Anti-apoptotic Bcl-2 family proteins have been reported to play an important role in apoptotic cell death of human malignancies. The aim of this study was to delineate the mechanism of anti-apoptotic Bcl-2 family proteins in pancreatic cancer (PaCa) cell survival. We first analyzed the endogenous expression and subcellular localization of anti-apoptotic Bcl-2 family proteins in six PaCa cell lines by Western blot. To delineate the functional role of Bcl-2 family proteins, siRNA-mediated knock-down of protein expression was used. Apoptosis was measured by Cell Death ELISA and Hoechst 33258 staining. In the results, the expression of anti-apoptotic Bcl-2 family proteins varied between PaCa cell lines. Mcl-1 knock-down resulted in marked cleavage of PARP and induction of apoptosis. Down-regulation of Bcl-2 or Bcl-xL had a much weaker effect. Simultaneous knock-down of Bcl-xL and Mcl-1 strongly induced apoptosis, but simultaneous knock-down of Bcl-xL/Bcl-2 or Mcl-1/Bcl-2 had no additive effect. The apoptosis-inducing effect of simultaneous knock-down of Bcl-xL and Mcl-1 was associated with translocation of Bax from the cytosol to the mitochondrial membrane, cytochrome c release, and caspase activation. These results demonstrated that Bcl-xL and Mcl-1 play an important role in pancreatic cancer cell survival. Targeting both Bcl-xL and Mcl-1 may be an intriguing therapeutic strategy in PaCa.

Successful combination chemotherapy with irinotecan hydrochloride and cisplatin for primary gastric small cell carcinoma: report of a case.

Primary gastric small cell carcinoma is a rare and aggressive malignant disease with a poor prognosis that was first reported in 1976 by Matsusaka et al. The incidence is very low and the clinicopathological features are similar to those of small cell lung carcinoma.We herein report a case of successful treatment by combination chemotherapy consisting of irinotecan hydrochloride and cisplatin for primary gastric small cell carcinoma. The patient was a 71-year-old male who was admitted to a local hospital with anemia. Gastrointestinal endoscopy revealed the presence of advanced gastric carcinoma at the upper region of the stomach. The patient underwent surgery, and the pathological diagnosis was small cell carcinoma due to the presence of the typical features of small round cells with scant cytoplasm that were positive for synaptophysin and chromogranin A in the resected specimen. The patient underwent subsequent combination chemotherapy, which provided him with over 1 year of survival and a good quality of life. We also present a review of the literature regarding chemotherapy for primary gastric small cell carcinoma.

Baicalein, a component of Scutellaria baicalensis, induces apoptosis by Mcl-1 down-regulation in human pancreatic cancer cells.

Scutellaria baicalensis (SB) and SB-derived polyphenols possess anti-proliferative activities in several cancers, including pancreatic cancer (PaCa). However, the precise molecular mechanisms have not been fully defined. SB extract and SB-derived polyphenols (wogonin, baicalin, and baicalein) were used to determine their anti-proliferative mechanisms. Baicalein significantly inhibited the proliferation of PaCa cell lines in a dose-dependent manner, whereas wogonin and baicalin exhibited a much less robust effect. Treatment with baicalein induced apoptosis with release of cytochrome c from mitochondria, and activation of caspase-3 and -7 and PARP. The general caspase inhibitor zVAD-fmk reversed baicalein-induced apoptosis, indicating a caspase-dependent mechanism. Baicalein decreased expression of Mcl-1, an anti-apoptotic member of the Bcl-2 protein family, presumably through a transcriptional mechanism. Genetic knockdown of Mcl-1 resulted in marked induction of apoptosis. The effect of baicalein on apoptosis was significantly attenuated by Mcl-1 over-expression, suggesting a critical role of Mcl-1 in this process. Our results provide evidence that baicalein induces apoptosis in pancreatic cancer cells through down-regulation of the anti-apoptotic Mcl-1 protein.

microRNA expression profile in undifferentiated gastric cancer.

Prognosis of patients with undifferentiated gastric cancer is generally poor. The expression of various microRNAs (miRNAs) has not been comprehensively investigated in undifferentiated gastric cancer. Total RNA was extracted from the specimens of 42 undifferentiated gastric cancer tissues and paired normal gastric tissue. Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was performed for a set of 72 miRNAs. The expression of each miRNA relative to the internal control RNA was determined using the 2-DeltaCt method. The expression levels of 3 miRNAs (mir-34b, mir-34c and mir-128a) were significantly upregulated and those of 3 miRNAs (mir-128b, mir-129 and mir-148) were downregulated in undifferentiated gastric cancer tissue when compared with those of the paired normal tissues. The probability of survival was significantly lower in patients with high expression levels of mir-20b or 150. There was a correlation between mir-27a and lymph node metastasis. Our investigation provides a list of candidate miRNAs that may be associated with the prognosis in undifferentiated gastric cancer patients. Further study is warranted to identify the target genes of these miRNAs and their function.

Gastric schwannoma with adjacent external progression harbored aberrant NF2 gene.

Gastric schwannomas are rare benign mesenchymal tumors. We describe a schwannoma of gastric origin with adjacent external progression. Sections showed a spindle cell tumor arranged in interlaced bundles and fascicles that was S-100 and CD34 positive but c-KIT protein negative. Histology and immunohistochemistry revealed the typical appearance of a gastric schwannoma. Genetic evaluation revealed that the tumor harbored a point mutation in exon 6 of the tumor suppressor neurofibromatosis 2 (NF2) gene, which resulted in an amino acid substitution of NF2 protein, and no mutation in exon 4b of the NF1 gene. In conclusion, we identified a rare mutation of the NF2 gene in gastric schwannoma. A diagnosis can only be definitive when based on histological and immunohistochemical findings. Digestive tract schwannomas are rare mesenchymal tumors that are differentiated from gastrointestinal stromal tumors by the absence of KIT protein. Follow up suggested that complete resection is an effective long-term treatment strategy.

Eicosapentaenoic acid suppresses angiogenesis via reducing secretion of IL­6 and VEGF from colon cancer­associated fibroblasts.

Eicosapentaenoic acid (EPA) improves interleukin (IL)­6 hypercytokinemia in patients with advanced cancer due to its anti­inflammatory effects. This EPA mechanism has been revealed to lead to several anticancer effects. While the effects of EPA on cancer cells have been investigated, particularly in terms of angiogenesis, its effects on the tumor stroma remain unclear. In the present study, the authors clarified the role of EPA in cancer angiogenesis against colon cancer­associated fibroblasts (CAFs) from the colon stroma. With established human CAFs and normal fibroblasts from colon stroma (NFs), the authors evaluated IL­6 and vascular endothelial growth factor (VEGF) secretion with or without EPA treatment using ELISA. The signal inhibition of mitogen­activated protein kinase (ERK) in CAFs by EPA was evaluated using western blotting. In vitro anti­angiogenesis effects were evaluated by the angiogenesis assay on Matrigel using human umbilical vein endothelial cells (HUVECs) cultured with the supernatant obtained from CAF cultures with or without EPA. IL­6 secretion was greater from CAFs compared with that from NFs and stimulation with lipopolysaccharide (LPS) resulted in greater IL­6 secretion from the two fibroblast types compared with that from fibroblasts without LPS stimulation. While LPS stimulation increased VEGF secretion from the two fibroblast types, EPA decreased IL­6 and VEGF secretion from CAFs. Western blotting revealed that the addition of 30 µM EPA inhibited the ERK phosphorylation signal in CAFs. Furthermore, the angiogenesis assay with Matrigel revealed that the CAF culture supernatants treated with EPA suppressed tubular formation in HUVECs. These reductions may have been caused by the inhibition of ERK phosphorylation by EPA. Thus, EPA reduces cancer angiogenesis associated with CAFs. Additional studies will be needed to clarify the continuous anti­angiogenetic effect of chemotherapy using angiogenesis inhibitors (e.g. bevacizumab and aflibercept) in conjunction with or without EPA, and the clinical usage of EPA in conjunction with chemotherapy in vivo.

Targeting beta1 integrin restores sensitivity to docetaxel of esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a common and highly fatal cancer in Japan. Systemic chemotherapy is used, but some tumors show resistance to it. The mechanisms of tumor resistance to chemotherapy remain largely unknown. We determined the chemosensitivity of 15 ESCC cell lines (TE-1-5, TE-8-15, KYSE140 and KYSE150) to docetaxel by clonogenic and MTT assays. We used cDNA microarray analysis and quantitative RT-PCR to determine which genes might determine resistance to docetaxel. Small interfering RNA (siRNA) was used to suppress gene expression and its effect on the chemosensitivity of the cell was determined. The cell line with the most resistance to docetaxel was TE-2. Using microarray analysis, we identified beta1 integrin (ITGB1) to be overexpressed in this cell line. Higher expression of ITGB1 mRNA was significantly associated with docetaxel resistance (n=15, r2=0.66, P=0.0110). Suppression of ITGB1 expression using siRNA sensitized the TE-2 cells to docetaxel. These data suggest that overexpression of ITGB1 may be related to resistance to chemotherapy and that targeting ITGB1, particularly in patients on docetaxel therapy, may enhance the effect of chemotherapy in patients with ESCC.

Decreased expression of RUNX3 is correlated with tumor progression and poor prognosis in patients with esophageal squamous cell carcinoma.

Runt-related transcription factor 3 (RUNX3) has been reported to be a candidate tumor suppressor gene in gastric cancer. However, in esophageal cancer, the role of RUNX3 has not been studied. The expression of RUNX3 mRNA was quantified by real-time reverse transcription polymerase chain reaction using Taq Man PCR in 15 esophageal cancer cell lines (TE1-15) and 70 esophageal squamous cell carcinoma (ESCC) specimens and their paired normal esophageal mucosa. The data were analyzed with reference to clinicopathological factors. Using specific primers, methylation of the promoter region of RUNX3 was examined. RUNX3 mRNA expression in ESCC tissue was significantly lower than that in the corresponding normal esophageal mucosa (3.913+/-4.617 vs. 7.795+/-15.361, P=0.0345). RUNX3 mRNA expression levels in locally invasive T4 tumors were significantly lower than those in less invasive T1-3 tumors (P=0.0454). Patients who had low RUNX3 mRNA expression levels had a significantly shorter survival after surgery compared with patients who had high RUNX3 mRNA expression (P=0.0299). Among the 15 esophageal cancer cell lines studied, one had methylation of the promoter region of RUNX3. Only 4 in 70 ESCC tumors had methylation in this region. In conclusion, RUNX3 expression may be involved in the tumor invasion and poor prognosis of patients with ESCC. The methylation of the RUNX3 promoter region in esophageal cancer is rare. A study on the mechanisms that underlie the reduced expression of RUNX3 in ESCC is warranted.

[Marked response to combination chemotherapy using S-1, CPT-11 for lymph node metastasis of gastric cancer].

A 68-year-old man with lymph node metastasis of stomach pylorus pointed out by abdominal CT, was diagnosed as gastric cancer of the stomach pyloric region. Although an operation was performed, the lymph node metastasis of No. 13 had invaded the pancreas, and curative resection of the lymph node was impossible. After the operation, he was given combination chemotherapy with PTX combined S-1, and CDDP combined S-1. Progressive disease (PD) was confirmed by abdominal CT after both combination chemotherapies. Next, he was given combination chemotherapy with S-1 and CPT-11 (S-1 100 mg/body, day 1-14, CPT-11 125 mg/m(2) day 1 and 15 every 4 weeks). Disappearance of the lymph node metastasis and decrease of CA19-9 were confirmed after combination chemotherapy with S-1 and CPT-11. After six courses of the chemotherapy, recurrences are no longer seen. S-1+CPT-11 chemotherapy is considered very useful because the adverse events of this chemotherapy have been mild.

A post operative complication of foramen of Winslow hernia with left to right herniation of the small intestine: An extremely rare case report.

INTRODUCTION: A foramen of Winslow hernia (FWH) is a type of internal hernias. Generally, the contents of the hernia pass through the foramen of Winslow from right to left. The case presented in this report is very unusual, as the small intestine in the hernia passed through the foramen from left to right. PRESENTATION OF CASE: A 67-year-old woman developed a sudden abdominal pain 15 days after laparoscopic subtotal colectomy. Abdominal contrast-enhanced computed tomography (CT) examination revealed a FWH, and an emergency surgery was scheduled. The small intestine was found to be herniating from the cavity of the omental bursa through the foramen of Winslow, to the right side of the hepatoduodenal ligament, and was incarcerated. The incarcerated intestine was reduced, and the necrotic part of the intestine was resected. In addition, the foramen of Winslow and the cavity of omental bursa were closed to prevent relapse. CONCLUSION: To our knowledge, here we report the first FWH of which the contents of the hernia are herniated from left to right, in literature. Whether the Foramen should be closed or not requires discussion, however, we conclude that the foramen should be closed when possible, acknowledging previous reports and the present case.

Apigenin induces apoptosis by suppressing Bcl-xl and Mcl-1 simultaneously via signal transducer and activator of transcription 3 signaling in colon cancer.

Apigenin is a natural flavonoid that exhibits anti-proliferative activity and induces apoptosis in various types of cancer, including colon cancer. The aim of the present study was to determine the mechanism underlying the apoptosis-inducing effect of apigenin in colon cancer. Apigenin reduced the proliferation of colon cancer cell lines, stimulated the cleavage of PARP and induced apoptosis in a dose-dependent manner. Apigenin treatment also suppressed the expression of the anti-apoptotic proteins Bcl-xL and Mcl-1. Small interfering RNA was used to knockdown Bcl-xL and Mcl-1 expression alone and in concert, and the proliferation and apoptosis of cancer cells were subsequently measured. The knockdown of Bcl-xL and Mcl-1 expression together markedly suppressed cell proliferation and induced apoptosis. Apigenin treatment also inhibited the phosphorylation of signal transducer and activator of transcription 3 (STAT3), which targets Bcl-xL and Mcl-1. The results of the current study therefore determined that apigenin induces the apoptosis of colon cancer cells by inhibiting the phosphorylation of STAT3 and consequently downregulates the anti-apoptotic proteins Bcl-xL and Mcl-1.

A novel gene, RSRC2, inhibits cell proliferation and affects survival in esophageal cancer patients.

In Japan and China, esophageal cancer is common and more than 90% of esophageal cancers are squamous cell carcinoma. Esophageal squamous cell carcinoma (ESCC) shows a poor prognosis, but the mechanism of ESCC and target genes for treatment remains unclear. We searched for genes related to ESCC, and identified a novel gene, FLJ11021, which was designated arginine/serine-rich coiled-coil 2 (RSRC2). We sought to determine the role of RSRC2 in the proliferation of esophageal cell lines and to examine the relationship between RSRC2 and clinicopathologic factors and ESCC prognosis. Expression of RSRC2 was quantified by real-time reverse transcription polymerase chain reaction (RT-PCR) in 70 primary ESCCs and paired noncancerous esophageal mucosa. To determine the role of RSRC2 in ESCC cell proliferation, we used vector-based transfection and small interfering RNA methods. Our results show that RSRC2mRNA levels in all ESCC cell lines (TE1-15, excluding TE7) were lower than those in a human esophageal squamous epithelial cell line (Het-1A). Cell proliferation of an ESCC cell line was inhibited by overexpression of RSRC2, while reduced expression was accompanied by tumor progression. RSRC2 expression levels were significantly correlated with depth of invasion, lymph node metastasis, lymphatic invasion and vascular invasion. Moreover, ESCC patients with low RSRC2mRNA expression had significantly shorter post-operative survival time than those with high expression. In vitro study revealed that RSRC2 might play a role in cell proliferation. Our study demonstrated that RSRC2 expression may be a novel tumor suppressor of esophageal cancer cell growth and a prognostic factor in ESCC.

The overexpression of caveolin-1 and caveolin-2 correlates with a poor prognosis and tumor progression in esophageal squamous cell carcinoma.

Caveolin-1 (CAV1) and caveolin-2 (CAV2) are the major structural proteins of caveolae. We investigated the relationship between the clinicopathological factors of esophageal squamous cell carcinoma (ESCC) and the expression of CAV1 and CAV2. CAV1 and CAV2 expression were analyzed by quantitative reverse transcription-polymerase chain reaction (RT-PCR) in 15 esophageal cancer cell lines (TE1-15) and a normal esophageal epithelium cell line (Het-1A). CAV1 and CAV2 expression was examined by RT-PCR and immunohistochemical analysis in 47 ESCC specimens. High levels of CAV1 and CAV2 mRNA were detected in TE1-15, but neither CAV1 nor CAV2 mRNA were detected in Het-1A. In the ESCC samples CAV1 and CAV2 mRNA expression in the ESCC samples were significantly higher than in the corresponding normal esophageal mucosa (CAV1, P=0.0024; CAV2, P=0.0136). However, we could not find any significant relationship between CAV1 or CAV2 mRNA expression and clinicopathological factors. Immunostaining for CAV1 was positive in 13 of 47 patients (27.7%), whereas CAV2 was positive in 22 of 47 patients (46.8%). A significant correlation was observed between CAV1 and CAV2 immunostaining and T factor, lymphatic invasion, vein invasion and differentiation. The patients with positive staining for CAV1 or CAV2 had a significantly shorter survival than those with negative staining (P=0.0105 and 0.0424 for CAV1 and CAV2, respectively). These results suggest that positive staining for CAV1 and CAV2 could be a potentially useful prognostic marker of ESCC.