Surgical resection of colorectal recurrence of gastric cancer more than 5 years after primary resection.

INTRODUCTION: Intestinal metastasis from gastric cancer is rare, although the most common cause of secondary neoplastic infiltration of the colon is gastric cancer. However, little data is available on recurrence or death in patients with gastric cancer surviving >5 years post-gastrectomy. Here we report two cases of lower intestinal metastasis from gastric cancer >5 years after primary resection and discuss with reference to the literature. PRESENTATION OF CASE: Case 1: A 61-year-old man with a history of total gastrectomy for gastric cancer 9 years earlier was referred to our hospital with constipation and abdominal distention. We diagnosed primary colon cancer and subsequently performed extended left hemicolectomy. Histological examination revealed poorly differentiated adenocarcinoma resembling the gastric tumor he had 9 years earlier. The patient refused postoperative adjuvant chemotherapy and remained alive with cancerous peritonitis and skin metastases as of 17 months later. Case 2: A 46-year-old woman with a history of total gastrectomy for gastric cancer 9 years earlier presented with constipation. She also had a history of Krukenberg tumor 3 years earlier. We diagnosed metastatic rectal cancer and subsequently performed low anterior resection and hysterectomy. Pathological examination revealed poorly differentiated tubular adenocarcinoma, resembling the gastric tumor. The patient remained alive without recurrence as of 17 months later. DISCUSSION: We found 19 reported cases of patients with resection of colon metastases from gastric cancer. Median disease-free interval was 74 months. CONCLUSION: Resection of late-onset colorectal recurrence from gastric cancer appears worthwhile for selected patients.

Characterization of an Opa interacting protein 5 involved in lung and esophageal carcinogenesis.

To identify potential molecular targets for diagnosis, treatment and/or prevention of lung and esophageal carcinomas, we screened for genes that were overexpressed in tumors through gene expression analyses of 120 lung cancers and 19 esophageal squamous-cell carcinomas using a cDNA microarray consisting of 27,648 cDNA or expressed sequence tags. In this process, we identified a gene, Opa interacting protein 5 (OIP5), to be highly transactivated in the majority of lung and esophageal cancers. Immunohistochemical staining using 336 archived non-small cell lung cancers and 305 esophageal squamous-cell carcinomas specimens demonstrated that OIP5 expression was significantly associated with poor prognosis of lung and esophageal cancer patients (P = 0.0053 and 0.0168, respectively), and multivariate analysis confirmed its independent prognostic value for non-small cell lung cancers (P = 0.0112). Suppression of OIP5 expression with siRNA effectively suppressed the growth of cancer cells, whereas the exogenous expression of OIP5 enhanced the growth of cancer cells. In addition, OIP5 protein is likely to be stabilized through its interaction with Raf1. OIP5 is a promising target for developing new prognostic biomarkers and anti-cancer drugs.

Phosphorylation and activation of cell division cycle associated 5 by mitogen-activated protein kinase play a crucial role in human lung carcinogenesis.

We analyzed the gene expression profiles of clinical lung carcinomas using a cDNA microarray containing 27,648 genes or expressed sequence tags, and identified CDCA5 (cell division cycle associated 5) to be upregulated in the majority of lung cancers. Tumor tissue microarray analysis of 262 non-small cell lung cancer patients revealed that CDCA5 positivity was an independent prognostic factor for lung cancer patients. Suppression of CDCA5 expression with siRNAs inhibited the growth of lung cancer cells; concordantly, induction of exogenous expression of CDCA5 conferred growth-promoting activity in mammalian cells. We also found that extracellular signal-regulated kinase (ERK) kinase phosphorylated CDCA5 at Ser79 and Ser209 in vivo. Exogenous expression of phospho-mimicking CDCA5 protein whose Ser209 residue was replaced with glutamine acid further enhanced the growth of cancer cells. In addition, functional inhibition of the interaction between CDCA5 and ERK kinase by a cell-permeable peptide corresponding to a 20-amino-acid sequence part of CDCA5, which included the Ser209 phosphorylation site by ERK, significantly reduced phosphorylation of CDCA5 and resulted in growth suppression of lung cancer cells. Our data suggest that transactivation of CDCA5 and its phosphorylation at Ser209 by ERK play an important role in lung cancer proliferation, and that the selective suppression of the ERK-CDCA5 pathway could be a promising strategy for cancer therapy.

Wnt inhibitor Dickkopf-1 as a target for passive cancer immunotherapy.

Dickkopf-1 (DKK1) is an inhibitor of Wnt/beta-catenin signaling that is overexpressed in most lung and esophageal cancers. Here, we show its utility as a serum biomarker for a wide range of human cancers, and we offer evidence favoring the potential application of anti-DKK1 antibodies for cancer treatment. Using an original ELISA system, high levels of DKK1 protein were found in serologic samples from 906 patients with cancers of the pancreas, stomach, liver, bile duct, breast, and cervix, which also showed elevated expression levels of DKK1. Additionally, anti-DKK1 antibody inhibited the invasive activity and the growth of cancer cells in vitro and suppressed the growth of engrafted tumors in vivo. Tumor tissues treated with anti-DKK1 displayed significant fibrotic changes and a decrease in viable cancer cells without apparent toxicity in mice. Our findings suggest DKK1 as a serum biomarker for screening against a variety of cancers, and anti-DKK1 antibodies as potential theranostic tools for diagnosis and treatment of cancer.

Activation of an oncogenic TBC1D7 (TBC1 domain family, member 7) protein in pulmonary carcinogenesis.

To develop novel biomarkers and therapeutic agents for lung cancers, we screened molecules that were highly expressed in lung cancers by means of cDNA microarray analysis and found an elevated expression of TBC1 domain family, member 7 (TBC1D7) in the majority of lung cancers. Northern-blot analysis using mRNAs from 16 normal tissues detected its expression only in testis. Immunohistochemical staining using tumor tissue microarrays consisting of 261 archived non-small cell lung cancer (NSCLC) specimens suggested an association of TBC1D7 expression with poor prognosis for NSCLC patients (P = 0.0063). Treatment of lung cancer cells using siRNA against TBC1D7, suppressed its expression and resulted in inhibition of the cell growth. Furthermore, the induction of exogenous expression of TBC1D7 conferred growth-promoting activity at in vitro and in vivo conditions. We also identified TBC1D7 to interact with TSC1 protein in lung cancer cells. TSC1 introduction into cells increased the level of TBC1D7 protein, whereas knockdown of TSC1 expression decreased the level of TBC1D7 protein, suggesting that TBC1D7 is stabilized probably through interaction with TSC1. In addition, inhibition of the binding between TBC1D7 and TSC1 by a TBC1D7-derived 20-amino acid cell-permeable peptide (11R-TBC1D7(152-171)), which corresponded to the binding domain to TSC1, effectively suppressed growth of lung cancer cells. Selective suppression of TBC1D7 and/or inhibition of the TBC1D7-TSC1 complex formation could be promising therapeutic strategies for lung cancer therapy.

Activation of WD repeat and high-mobility group box DNA binding protein 1 in pulmonary and esophageal carcinogenesis.

PURPOSE: We attempted to identify novel biomarkers and therapeutic targets for lung and esophageal cancers. EXPERIMENTAL DESIGN: We screened for genes that were overexpressed in a large proportion of lung and esophageal carcinomas using a cDNA microarray representing 27,648 genes or expressed sequence tags. A gene encoding WDHD1, a WD repeat and high-mobility group box DNA binding protein 1, was selected as a candidate. Tumor tissue microarray containing 267 archival non-small cell lung cancers and 283 esophageal squamous cell carcinomas (ESCC) was used to investigate the clinicopathologic significance of WDHD1 expression. The role of WDHD1 in cancer cell growth and/or survival was examined by small interfering RNA experiments and cell growth assays. The mechanism of WDHD1 activation through its phosphorylation in cancer cells was examined by immunoprecipitation and kinase assays. RESULTS: Positive WDHD1 immunostaining was associated with a poor prognosis for patients with non-small cell lung cancer (P = 0.0403) as well as ESCC (P = 0.0426). Multivariate analysis indicated it to be an independent prognostic factor for ESCC (P = 0.0104). Suppression of WDHD1 expression with small interfering RNAs effectively suppressed lung and esophageal cancer cell growth. In addition, induction of the exogenous expression of WDHD1 promoted the growth of mammalian cells. AKT1 kinase seemed to phosphorylate and stabilize the WDHD1 protein in cancer cells. CONCLUSIONS: WDHD1 expression is likely to play an important role in lung and esophageal carcinogenesis as a cell cycle regulator and a downstream molecule in the phosphoinositide 3-kinase/AKT pathway, and that WDHD1 is a candidate biomarker and a promising therapeutic target for cancer.