[Successful Weekly Nanoparticle Albumin-Bound Paclitaxel Therapy for a Case of Gastric Cancer with Oncological Emergency of Liver Metastasis].

An 82-year-old man with far-advanced gastric cancer underwent palliative distal gastrectomy. After operation, he was treated with S-1 therapy and maintained stable disease during 3 courses of chemotherapy. However, he stopped taking the drug according to self-judgment. After that, he was admitted to our hospital because of jaundice and general malaise. We diagnosed oncologic emergency with liver metastasis. He was treated with weekly nanoparticle albumin-bound paclitaxel. After 1 course of chemotherapy, his symptoms were improved and he was discharged. In the case of an oncologic emergency, proper administration of an anticancer drug may have a beneficial effect in patients. Herein, we report a case of recovery from an oncologic emergency by chemotherapy.

Overexpression of Lysophosphatidylcholine Acyltransferase 1 and Concomitant Lipid Alterations in Gastric Cancer.

BACKGROUND: The involvement of lipids in carcinogenic and developmental processes has been reported in some malignancies, but their roles in gastric cancer remain to be analyzed. In this study, we compared the lipid content of gastric cancer tissue and adjacent nonneoplastic mucosa using imaging mass spectrometry. METHODS: Mass spectra were acquired from 12 sections of human gastric cancer tissue and adjacent nonneoplastic mucosa using a matrix-assisted laser desorption-ionization time-of-flight tandem mass spectrometry type mass spectrometer equipped with a 355 nm Nd:YAG laser. Protein expression of lysophosphatidylcholine acyltransferase 1 (LPCAT1), which converts lysophosphatidylcholine (LPC) to phosphatidylcholine (PC) in the presence of acyl-CoA in Lands' cycle, was immunohistochemically analyzed in 182 gastric cancer specimens. RESULTS: The averaged mass spectra from the cancer tissue and nonneoplastic mucosa were identical. Most of the signals that differed between cancer tissue and nonneoplastic mucosa corresponded to phospholipids, the majority of which were PC and LPC. Two signals, m/z 798.5 and 496.3, were higher and lower, respectively, in cancer tissues, predominantly in differentiated adenocarcinoma. A database search enabled identification of the ions at m/z 798.5 and m/z 496.3 as potassium-adducted PC (16:0/18:1) and proton-adducted LPC (16:0), respectively. Immunohistochemical analysis revealed that LPCAT1 was highly expressed in cancer lesions compared to nonneoplastic mucosa, predominantly in differentiated adenocarcinoma. LPCAT1 expression levels correlated positively with tumor differentiation and negatively with tumor depth, lymph node metastasis, and tumor stage. CONCLUSIONS: Overexpressed LPCAT1 protein in gastric mucosa appears to play important roles in the tumorigenic process of gastric cancer by converting LPC to PC.

Microarray analysis reveals distinct gene set profiles for gastric and intestinal gastrointestinal stromal tumors.

AIM: We sought to address the mechanisms by which intestinal gastrointestinal stromal tumors (GIST) have a markedly higher risk of recurrence than gastric GISTs. MATERIALS AND METHODS: Gene expression levels were compared among six primary gastric, three intestinal and six metastatic liver GISTs using cDNA microarray. Protein levels of Slit homolog 2 (SLIT2) were analyzed by immunohistochemistry in 25 primary gastric and 10 intestinal GIST. RESULTS: Intestinal GIST had gene expression profiles similar to clinically malignant and metastatic GIST. In gene set-enrichment analysis, the gene sets MITOTIC_CELL CYCLE and NEURON_DIFFERENTIATION were up-regulated and down-regulated, respectively, in intestinal GIST compared to gastric GIST. High-risk gastric GISTs and intestinal GIST, expressed similar levels of SLIT2 protein, which were lower than those of low-risk gastric GISTs. CONCLUSION: The gene-expression profile of intestinal GISTs was similar to that of metastatic liver GISTs. Besides higher proliferative activity, down-regulation of SLIT2 might be involved in clinically malignant phenotypes of intestinal GIST.

Anti-VEGF antibody therapy induces tumor hypoxia and stanniocalcin 2 expression and potentiates growth of human colon cancer xenografts.

Tumor angiogenesis plays a critical role in colorectal cancer progression. Recent randomized clinical trials have revealed the additive effect of bevacizumab, a humanized monoclonal antibody against vascular endothelial growth factor (VEGF)-A, to conventional chemotherapy in the improved survival of patients with metastatic colorectal cancer. However, a number of preclinical reports indicate the development of resistance to anti-angiogenic therapy. In this study, we addressed the effects of anti-VEGF antibodies on the growth and malignant behavior of colorectal cancer cells. TK-4, a solid tumor strain derived from a colon cancer patient, was subcutaneously or orthotopically implanted into nude mice. Short-term administration of anti-VEGF antibodies inhibited the growth of cecal tumors at day 14 by suppressing mitosis, but prolonged treatment resulted in the recovery of cellular proliferation and suppression of apoptosis at day 35. Intratumoral hypoxia induced by anti-VEGF antibody treatment resulted in activation of hypoxia inducible factor-1α protein and an increased number of aldehyde dehydrogenase 1-positive tumor cells. In microarray analysis, stanniocalcin 2 (STC2) was the most highly upregulated gene in anti-VEGF antibody-treated tumors. In vitro analyses showed that the growth and migration of SW480 colon cancer cells under hypoxic conditions were significantly inhibited by knockdown of STC2. In vivo serial transplantation of TK-4 revealed that long-term administration of anti-VEGF antibodies increased the tumorigenicity of colon cancers and accelerated tumor growth when transplanted into secondary recipient mice. Our data provide a potential molecular explanation for the limited clinical effectiveness of anti-VEGF antibodies.

Rapid relapse after resection of a sunitinib-resistant gastrointestinal stromal tumor harboring a secondary mutation in exon 13 of the c-KIT gene.

We describe a case with rapid relapse after resection of a sunitinib-resistant gastrointestinal stromal tumor (GIST). Liver metastases and foci of left retroperitoneal recurrence developed during adjuvant imatinib treatment. The tumors did not shrink after sunitinib treatment, and hepatectomy and retroperitoneal tumorectomy were performed. Histological examination showed a Ki67 labeling index of over 50% in viable tumor cells. Genomic analysis revealed mutations in exons 11 and 13 of the c-KIT gene. Computed-tomographic scan revealed retroperitoneal recurrence at the surgical site five weeks post-operatively. In this case, high proliferative activity of the recurrent foci was associated with resistance to sunitinib and rapid recurrence during the perioperative withdrawal of sunitinib. It is important to consider the possibility of an exon 13 mutation with an aggressive phenotype when treating sunitinib-resistant GISTs. Surgical intervention for sunitinib-resistant GISTs should be carefully considered if R0 resection is not possible.

Surgical intervention for imatinib and sunitinib-resistant gastrointestinal stromal tumors.

Imatinib mesylate is an effective treatment for recurrent or metastatic gastrointestinal stromal tumors (GISTs), but secondary resistance has been reported. The tyrosine kinase inhibitor sunitinib malate has shown efficacy in imatinib-resistant GISTs, and has been used as second-line therapy for recurrent or metastatic GISTs. However, it is often difficult to treat patients with imatinib- and sunitinib-resistant GISTs. In this report, we describe a case of surgically resected liver and peritoneal recurrences of GISTs that arose polyclonally and were resistant to imatinib and sunitinib. A 67-year-old man was referred to our hospital with multiple recurrent GISTs after failed imatinib treatment. Sunitinib was administered at 50 mg/day for 4 weeks with 2-week intervals between treatments. Some of the recurrent GISTs were sensitive, but others were resistant, and progressive disease was diagnosed. Extended left hepatectomy and peritoneal tumorectomy were performed. Histologically, tumors sensitive to sunitinib showed degenerative changes, while the resistant tumors consisted of KIT-positive, viable GIST cells. The primary mutation in all the tumors consisted of a deletion at nucleotides 555-560 with an E554D point mutation at exon 11 of the c-kit gene. The sunitinib-resistant liver and peritoneal tumors had different point mutations: T to G and T to A, respectively, although both resulted in an N822K amino acid alteration, indicating the polyclonal evolution of recurrent GISTs. Thus, if R0 resection is expected, surgical intervention under the control of imatinib or sunitinib should be considered for the control of metastatic or recurrent GISTs.

Microarray analysis identifies versican and CD9 as potent prognostic markers in gastric gastrointestinal stromal tumors.

Although the main cause of gastrointestinal stromal tumor (GIST) is gain-of-function mutations in the c-kit gene in the interstitial cells of Cajal, concomitant genetic or epigenetic changes other than c-kit appear to occur in the development of metastasis. We sought to identify the genes involved in the metastatic process of gastric GIST. Microarray analysis was performed to compare gene expressions between three gastric GIST and four metastatic liver GIST. Expression levels were higher for 165 genes and lower for 146 genes in metastatic liver GIST. The upregulation of five oncogenes and downregulation of four tumor suppressor genes including versican and CD9 were confirmed by quantitative reverse transcriptional PCR. Immunohistochemistry in 117 GIST revealed that protein levels of versican and CD9 were higher and lower, respectively, in metastatic GIST. High expression of versican and low expression of CD9 in 104 primary gastric GIST correlated with poor disease-free survival (P = 0.0078 and P = 0.0018). In addition to the c-kit gene mutation, genetic or epigenetic changes other than c-kit play important roles in the metastatic process. In particular, versican and CD9 are potential prognostic markers in gastric GIST.

Analysis of anatomic variants of mesenteric veins by 3-dimensional portography using multidetector-row computed tomography.

BACKGROUND: It is important to be aware of mesenteric venous variants to perform peripancreatic surgery. We investigated the usefulness of 3-dimensional (3-D) portography. METHODS: Vessels were reconstructed using computer software in 102 patients undergoing multidetector-row computed tomography (MDCT) scheduled for gastrointestinal or hepatobiliary-pancreatic surgery. RESULTS: The superior mesenteric vein (SMV) was composed of single and double trunks around the splenoportal confluence in 78 and 24 patients, respectively. The inferior mesenteric vein joined the splenic vein (68.5%), SMV (18.5%), and splenoportal confluence (7.6%). The left gastric vein joined the splenic vein (46.3%), portal vein (39.0%), and splenoportal confluence (14.7%). Seventy-nine patients showed a gastrocolic trunk, mostly composed of the right gastroepiploic vein and veins from the colonic hepatic flexure. Intraoperative findings were identical to 3-D diagnosis in 68 gastrectomized and 9 pancreatectomized patients. CONCLUSION: Although mesenteric venous tributaries are complex, 3-D portography is helpful for surgeons to safely perform peripancreatic surgery.

Imaging mass spectrometry of gastric carcinoma in formalin-fixed paraffin-embedded tissue microarray.

The popularity of imaging mass spectrometry (IMS) of tissue samples, which enables the direct scanning of tissue sections within a short time-period, has been considerably increasing in cancer proteomics. Most pathological specimens stored in medical institutes are formalin-fixed; thus, they had been regarded to be unsuitable for proteomic analyses, including IMS, until recently. Here, we report an easy-to-use screening method that enables the analysis of multiple samples in one experiment without extractions and purifications of proteins. We scanned, with an IMS technique, a tissue microarray (TMA) of formalin-fixed paraffin-embedded (FFPE) specimens. We detected a large amount of signals from trypsin-treated FFPE-TMA samples of gastric carcinoma tissues of different histological types. Of the signals detected, 54 were classified as signals specific to cancer with statistically significant differences between adenocarcinomas and normal tissues. We detected a total of 14 of the 54 signals as histological type-specific with the support of statistical analyses. Tandem MS revealed that a signal specific to poorly differentiated cancer tissue corresponded to histone H4. Finally, we verified the IMS-based finding by immunohistochemical analysis of more than 300 specimens spotted on TMAs; the immunoreactivity of histone H4 was remarkably strong in poorly differentiated cancer tissues. Thus, the application of IMS to FFPE-TMA can enable high-throughput analysis in cancer proteomics to aid in the understanding of molecular mechanisms underlying carcinogenesis, invasiveness, metastasis, and prognosis. Further, results obtained from the IMS of FFPE-TMA can be readily confirmed by commonly used immunohistochemical analyses.

Optical diagnosis of gastric cancer using near-infrared multichannel Raman spectroscopy with a 1064-nm excitation wavelength.

BACKGROUND: Gastric cancer is one of the most common cancers in Japan. The use of endoscopy is increasing, along with the number of histological examinations of specimens obtained by endoscopy. However, it takes several days to reach a diagnosis, which increases the medical expense. Raman spectroscopy is one of the available optical techniques, and the Raman spectrum for each molecule and tissue is characteristic and specific. The present study investigated whether Raman spectroscopy can be used to diagnose gastric cancer. METHODS: A total of 251 fresh biopsy specimens of gastric carcinoma and non-neoplastic mucosa were obtained from 49 gastric cancer patients at endoscopy. Without any pretreatment, the fresh specimens were measured with a near-infrared multichannel Raman spectroscopic system with an excitation wavelength of 1064 nm, and Raman spectra specific for the specimens were obtained. A principal component analysis (PCA) was performed to distinguish gastric cancer and non-neoplastic tissue, and a discriminant analysis was used to evaluate the accuracy of the gastric cancer diagnosis. RESULTS: The Raman spectra for cancer specimens differed from those for non-neoplastic specimens, especially at around 1644 cm(-1). Sensitivity was 66%, specificity was 73%, and accuracy was 70%. The accuracy of diagnosis using the single Raman scattering intensity at 1644 cm(-1) was 70%, consistent with the PCA result. CONCLUSIONS: The present results indicate that near-infrared multichannel Raman spectroscopy with a 1064-nm excitation wavelength is useful for gastric cancer diagnosis. Establishment of a Raman diagnostic system for gastric cancer may improve the clinical diagnosis of gastric cancer and be beneficial for patients.