Associations of Japanese food intake with survival of stomach and colorectal cancer: A prospective patient cohort study.

Dietary factors may affect the prognosis of digestive tract cancer, but evidence has been sparse. We investigated the association between pretreatment intake of 6 Japanese foods (including soy food, miso [soybean paste] soup and seaweed) and the risk of death among patients with histologically confirmed major digestive tract cancers (stomach, 1931; colon, 793; rectum, 510) diagnosed during 1997-2013 at a single institution in Japan. Pretreatment dietary intake was assessed using a food frequency questionnaire, and the patients were followed until December 2016. The Cox proportional hazards model was used to estimate hazard ratios (HR) and 95% confidence intervals (CI). Among the patients with stomach cancer, frequent intake of soy food was inversely associated with the risk of all-cause (Ptrend for four frequency groups = 0.01; HR = 0.72, 95% CI: 0.50-1.04 for highest vs lowest group) and stomach cancer (Ptrend  = 0.03; HR = 0.63, 95% CI: 0.40-0.99) death. A similar inverse association was also found for intake of miso soup. In contrast, frequent seaweed intake was inversely associated with the risk of all-cause death among the patients with colon cancer (Ptrend  = 0.03). Rectal cancer patients who had frequently consumed seaweed tended to have a lower risk of rectal cancer death (Ptrend  = 0.02). These findings indicate that pretreatment intake of Japanese foods such as soybean products and seaweed may have favorable effects on patient survival of stomach and colorectal cancer, although this needs to be confirmed by further research.

Associations of cigarette smoking and alcohol drinking with stomach cancer survival: A prospective patient cohort study in Japan.

Cigarette smoking and alcohol drinking may affect the prognosis of stomach cancer, but evidence has been inconsistent. We investigated the associations between pretreatment smoking and alcohol drinking and the risk of all-cause and stomach cancer death among 1,576 patients with histologically confirmed stomach cancer diagnosed during 1997-2010 at a single hospital in Japan. Histories of smoking and alcohol drinking were assessed using a self-administered questionnaire. The patients were followed until December 31, 2013. The Cox proportional hazards model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During 9,625.1 person-years, 670 all-cause and 419 stomach cancer deaths were documented. Among the patients overall, ever-drinking was significantly associated with an increased risk of all-cause death (HR: 1.25; 95% CI: 1.03-1.51), but not stomach cancer death. Positive linear associations with the frequency of drinking (ptrend = 0.02) and the amount of alcohol consumed per day (ptrend = 0.03) were observed for the risk of all-cause death. Ever-smoking was not related to either the risk of all-cause or stomach cancer death. Conversely, among the patients who underwent curative resection, a significant positive association was found between ever-smoking and the risk of stomach cancer death (HR: 2.44; 95% CI: 1.17-5.08). A positive association was also found for earlier age at start of smoking (ptrend = 0.0046). Pretreatment smoking and alcohol drinking have significant effects on stomach cancer survival. Lifestyle adjustments throughout life may improve survival.

Drug delivery of oral anti-cancer fluoropyrimidine agents.

INTRODUCTION: Sixty years since its introduction, 5-FU still forms the core of chemotherapy regimens for many types of malignancies. 5-FU is a time-dependent drug but is rapidly degraded in plasma by dihydropyrimidine dehydrogenase (DPD). Although originally developed in an intravenous form, 5-FU oral prodrugs were developed with the goal of improving efficacy and minimizing toxicity as well as to capitalize on the advantages of oral drug administration. The inactive 5-FU prodrug is gradually converted into the active form in the systemic circulation. UFT, S-1, and capecitabine are oral 5-FU prodrugs currently in clinical use. However, the efficacy of 5-FU can be further improved by its combination with DPD inhibitors and biochemical modulators, such as uracil and leucovorin, in addition to modifying administration schedules. Areas covered: We focused on the drug delivery of oral 5-FU prodrugs, their pharmacokinetics, and the development of DPD inhibitors. Since oral 5-FU prodrugs have been formulated into combination drugs, we also discussed the regulatory approval of combination drugs. Expert opinion: Many regimens that include intravenously administered 5-FU can be replaced by oral 5-FU prodrugs. Patients would benefit from development of combination 5-FU oral prodrug formulations and its associated path through the combination drug regulatory approval process.

Enhanced expression of the M2 isoform of pyruvate kinase is involved in gastric cancer development by regulating cancer-specific metabolism.

Recent studies have indicated that increased expression of the M2 isoform of pyruvate kinase (PKM2) is involved in glycolysis and tumor development. However, little is known about the role of PKM2 in gastric cancer (GC). Therefore, we examined the expression and function of PKM2 in human GC. We evaluated PKM1 and PKM2 expression by quantitative RT-PCR in gastric tissues from 10 patients who underwent gastric endoscopic submucosal dissection, 80 patients who underwent gastrectomy, and seven healthy volunteers, and analyzed the correlation with clinicopathological variables. To assess the function of PKM2, we generated PKM2-knockdown GC cells, and investigated the phenotypic changes. Furthermore, we examined the induction of PKM2 expression by cytotoxin-associated gene A (CagA), a pathogenic factor of Helicobacter pylori, using CagA-inducible GC cells. We found that PKM2 was predominantly expressed not only in GC lesions but also in the normal gastric regions of GC patients and in the gastric mucosa of healthy volunteers. The PKM2 expression was significantly higher in carcinoma compared to non-cancerous tissue and was associated with venous invasion. Knockdown of PKM2 in GC cells caused significant decreases in cellular proliferation, migration, anchorage-independent growth, and sphere formation in vitro, and in tumor growth and liver metastasis in vivo. The serine concentration-dependent cell proliferation was also inhibited by PKM2 silencing. Furthermore, we found that PKM2 expression was upregulated by CagA by way of the Erk pathway. These results suggested that enhanced PKM2 expression plays a pivotal role in the carcinogenesis and development of GC in part by regulating cancer-specific metabolism.

Enhanced expression of semaphorin 3E is involved in the gastric cancer development.

Semaphorins and their receptors are abnormally expressed in various cancers, but little is known about the expression and function of semaphorin 3E (SEMA3E) and its receptor, plexin D1 (PLXND1), in gastric cancer development or metastasis. We evaluated SEMA3E and PLXND1 expression by quantitative RT-PCR in gastric tissues from 62 patients who underwent gastrectomy and analyzed the correlation between their expression and clinicopathological variables. To assess the function of SEMA3E, we generated human gastric cancer cell lines with suppressed or increased SEMA3E expression. The expression level of SEMA3E, but not PLXND1, was correlated with lymph node involvement and metastatic progression in gastric cancer. A significant association was observed between a high level of SEMA3E expression and poor differentiation or poor survival in the intestinal type of gastric cancer. SEMA3E knockdown in gastric cancer cells attenuated cell proliferation and metastatic ability in vitro and in vivo. Moreover, SEMA3E caused cell proliferation and anchorage-independent cell growth in the intestinal type of gastric cancer. These results suggested that SEMA3E is likely to be involved in the development of gastric cancer and might also be a therapeutic target for its treatment.

The use of natural products in colorectal cancer drug discovery.

INTRODUCTION: Natural products (NPs) are evolutionarily designed and contain more complex and challenging structures than synthetic compounds. Since the 1980s, the pharmaceutical industry has gradually shifted to a strategy of developing targeted agents by screening libraries of synthetic compounds. However, NPs have recently received renewed focus as a rich repository for drug discovery. Irinotecan was developed as a derivative of camptothecin and was applied in standard regimens for metastatic colorectal cancer (CRC) worldwide. Additionally, polysaccharide K is approved for CRC in Japan and Taiwan in combination with cytotoxic agents. However, after the approval of irinotecan in 1996, no anti-cancer agents derived from NPs have been approved for CRC. AREAS COVERED: This review discusses NPs that are currently under investigation for the treatment of CRC. In addition, other NPs derived as purified ingredients and crude extracts are listed and also discussed. EXPERT OPINION: The use of NPs for the discovery of anti-cancer agents has not been fully investigated. New technologies that are currently applied for synthetic compounds may be utilized for anti-cancer drug discovery including NPs for CRC.

Family history, body mass index and survival in Japanese patients with stomach cancer: a prospective study.

Family history and nutritional status may affect the long-term prognosis of stomach cancer, but evidence is insufficient and inconsistent. To clarify the prognostic factors of stomach cancer, we conducted a prospective study of 1,033 Japanese patients with histologically confirmed stomach cancer who were admitted to a single hospital between 1997 and 2005. Family history of stomach cancer and pretreatment body mass index (BMI) were assessed using a self-administered questionnaire. Clinical data were retrieved from a hospital-based cancer registry. All patients were completely followed up until December, 2008. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated according to family history in parents and siblings and BMI category. During a median follow-up of 5.3 years, 403 all-cause and 279 stomach cancer deaths were documented. Although no association with family history was observed in the patients overall, analysis according to age group found an increased risk of all-cause death associated with a history in first degree relatives (HR = 1.61, 95% CI: 0.93-2.78, p = 0.09) and with a parental history (HR = 1.86, 95% CI: 1.06-3.26) among patients aged under 60 years at diagnosis. BMI was related to all-cause and stomach cancer death among patients aged 60 and over, showing a J-shaped pattern (HR of all-cause death = 2.28 for BMI < 18.5; HR = 1.61 for 25 ≤ vs. ≥ 23.0 to < 25.0 kg/m(2)). A family history of stomach cancer, especially parental history, may affect mortality among younger stomach cancer patients, whereas nutritional status may be a prognostic factor in older patients.

The preclinical development of regorafenib for the treatment of colorectal cancer.

INTRODUCTION: The RAS-RAF-MEK-ERK pathway is one of the best characterized kinase cascades. During the exploration of small molecules that inhibit RAF1 kinase, regorafenib (BAY 73-4506) was discovered as a multikinase inhibitor which demonstrated anti-cancer, anti-angiogenic, and apoptotic activities in metastatic colorectal cancer. This was not the first multikinase inhibitor discovered for the disease; indeed, before regorafenib was approved by FDA as a multikinase inhibitor for metastatic colorectal cancer in 2012, sorafenib (BAY 43-9006) had already been developed to be the first in the world as a multikinase inhibitor for malignancy. Indeed, the only difference between the two compounds is fluorine bound to its proximal phenyl ring although the end result is a considerably different profile, both as a kinase inhibitor as well as in its clinical application. AREAS COVERED: In this drug discovery case history, the authors review the design, discovery, and development of both regorafenib and sorafenib from back in the 1990s. Furthermore, the authors highlight the drug's anti-cancer and anti-angiogenic properties as well as its efficacy, safety pharmacology and toxicology based on FDA documents. EXPERT OPINION: In order to better predict the efficacy of kinase inhibitors and to utilize them more efficiently, our understanding of drug discovery, the approaches for kinase profiling, and technologies needed for their development are paramount. Indeed, the authors believe that the field should better explore the use of predictive biomarkers that might be able to better assess these therapeutics. Pharmaceutical scientists must also consider the cost effectiveness of the targeted agents developed as a number of the drugs developed are very expensive.

Enhanced expression of long non-coding RNA HOTAIR is associated with the development of gastric cancer.

The long non-coding RNA HOTAIR has been reported to be a poor prognostic biomarker in a variety of malignant tumors. However, little is known about the association of HOTAIR with gastric cancer. We examined the expression of HOTAIR in 68 gastric cancer samples using quantitative real-time RT-PCR and analyzed its correlation with the clinical parameters. The functional role of HOTAIR was examined by generating human gastric cancer cell lines with increased or suppressed HOTAIR expression. The anchorage -independent growth was assessed by soft agar assay. The increased or suppressed HOTAIR expressing gastric cancer cells were injected into the tail vein or peritoneal cavity of immunodeficient mice to examine the effect of this molecule on metastasis and peritoneal dissemination. The expression of HOTAIR was significantly higher in cancer lesions than in adjacent non-cancerous tissues in human gastric cancers. In the diffuse type of gastric cancer, the High-HOTAIR group (HOTAIR/GAPDH > 1) showed significantly more venous invasion, frequent lymph node metastases and a lower overall survival rate compared to the Low-HOTAIR group (HOTAIR/GAPDH < 1). Colony formation on the soft agar was enhanced in a HOTAIR-dependent manner. HOTAIR-expressing MKN74 formed more liver metastasis compared to control when they were injected into the tail vein of mice. In addition, reduced expression of HOTAIR in KATO III suppressed peritoneal dissemination. These results suggest that HOTAIR plays a pivotal role in the development of gastric cancer.

[A case of pancreatic endocrine tumor developing from intraductal papillary mucinous neoplasm (IPMN)].

In March, 2004, a 64-year-old man was given a diagnosis of IPMN of the pancreas in postoperative CT of left shoulder blade chondrosarcoma. In October, 2007, because a tumor in the pancreas body was found, distal pancreatectomy was performed a diagnosis of the poorly differentiated adenocarcinoma. Histopathologic diagnosis revealed as pancreatic endocrine tumor and immunity dyeing was useful for differential diagnosis. A case of pancreatic endocrine tumor developing from IPMN has a possibility not rare for frequency, but few reports are available so far.

Human sialidase as a cancer marker.

Altered sialylation of cell surface glycoproteins and glycolipids is closely related to the malignant phenotype of cancer cells, including the metastatic potential and invasiveness. Many cancer-related antigens in clinical use contain sialic acids at the terminal position of sugar chains in the molecules. To elucidate the molecular mechanism, we focused our investigation on sialidase, which catalyzes the removal of sialic acid residues from the glycoconjugates. Four types of human sialidases identified to date behave in different manners during carcinogenesis. One of the sialidases, found in the lysosomes, showed downregulation in cancers, promoting anchorage-independent growth, and metastatic ability, while another, found in the plasma membrane, showed marked upregulation, causing apoptosis suppression. It was found that estimation of the mRNA levels of sialidases by real-time PCR allowed discrimination of cancerous from noncancerous tissues and even determination of the pathological stage in some cancers. Immunohistochemistry of cancer tissues using the antibody against the plasma membrane sialidase was useful for clinical diagnosis. This paper briefly summarizes our findings of the altered sialidase expression in cancers and the possibility of their clinical application as cancer markers. Human sialidases are indeed related to malignancy and may be potential targets for cancer diagnosis and therapy.

Relation of serum levels of estrogen and dehydroepiandrosterone sulfate to hormone receptor status among postmenopausal women with breast cancer.

BACKGROUND: It is hypothesized that breast cancer may consist of heterogeneous diseases with different hormonal environments classified by hormone receptor status. Epidemiologic studies evaluating risk factors for breast cancer by hormone receptor status have supported the hypothesis. However, there are inconsistencies in the risk factor profiles by estrogen receptor (ER) and progesterone receptor (PR) across the studies. To clarify the heterogeneity of the disease, it is necessary to understand not only risk factor profiles but also the biologic characteristics such as the relationships among endogenous sex hormone levels and hormone receptors. METHODS: We measured serum levels of estrone (E1), estradiol (E2), dehydroepiandrosterone sulfate (DHEAS), and sex hormone-binding globulin (SHBG) in 142 postmenopausal women aged 50 and over with primary breast cancer who had undergone surgical treatment, and investigated the heterogeneity in the relations of endogenous sex hormone levels to hormone receptor status, using the case-series study method. Subjects were categorized into 3 classes based on tertiles of each hormone level in receptor-negative subjects, and odds ratios (ORs) for receptor-positive status compared with receptor-negative status were computed, taking the lowest category as a reference category. RESULTS: There were clear trends toward higher serum levels of E1, E2, and DHEAS in women with PR+ cancer. The case-series approach revealed that PR+ status might be strongly associated with serum sex hormone levels. In particular, the OR of PR+ was large for a high DHEAS level (OR for the highest category=4.28). No significant association between serum hormone levels and ER status was observed. CONCLUSION: The association of serum sex hormone levels with hormone receptor status may differ by PR status, but not by ER status. This finding suggests that PR status may be related to the heterogeneity in hormonal environments associated with breast cancer risk.

Outcomes after pylorus-preserving gastrectomy for early gastric cancer: a prospective multicenter trial.

The aim of the present study was to compare in a prospective, multicenter trial the results early and late after pylorus-preserving gastrectomy (PPG) versus conventional distal gastrectomy (CDG) with Billroth I anastomosis for early gastric cancer. Eighty-one patients with early gastric cancer were randomized and then underwent either PPG or CDG. Duration of operation, intraoperative blood loss, days until removal of the nasogastric tube, days until start of oral intake, and decrease in body weight were studied as parameters for outcomes early after the surgery. Late results were studied in patients followed for longer than 3 years. Change in body weight, status of oral intake, symptoms suggesting early dumping syndrome, and overall satisfaction were addressed in the questionnaire. The presence of gallstones was examined with ultrasonography. There were no differences in early results between PPG and CDG. The incidence of early dumping syndrome was lower in PPG (8%) than in CDG (33%). Other late results including the incidence of gallstones were not different between the 2 groups. These results indicate that PPG is as safe as CDG and has an advantage in terms of early dumping syndrome.