Progress toward hormonal therapy of gastrointestinal cancer

Metabolomics analysis of amino acid and fatty acids in colorectal cancer patients based on tandem mass spectrometry

Metabolic differences between colorectal cancer (CRC) and NI (NI) play an important role in early diagnoses and in-time treatments. We investigated the metabolic alterations between CRC patients and NI, and identified some potential biomarkers, and these biomarkers might be used as indicators for diagnosis of CRC. In this study, there were 79 NI, 50 CRC I patients, 52 CRC II patients, 56 CRC III patients, and 52 CRC IV patients. MS-MS was used to measure the metabolic alterations. Univariate and multivariate data analysis and metabolic pathway analysis were applied to analyze metabolic data and determine differential metabolites. These indicators revealed that amino acid and fatty acids could separate these groups. Several metabolites indicated an excellent variables capability in the separation of CRC patients and NI. Ornithine, arginine, octadecanoyl carnitine, palmitoyl carnitine, adipoyl carnitine, and butyryl carnitine/propanoyl carnitine were selected to distinguish the CRC patients and NI. And methionine and propanoyl carnitine, were directly linked to different stages of CRC. Receiver operating characteristics curves and variables importance in projection both represented an excellent performance of these metabolites. In conclusion, we assessed the difference between CRC patients and NI, which supports guidelines for an early diagnosis and effective treatment.

Cholecystokinin and gastrin receptors targeting in gastrointestinal cancer

Cholecystokinin and Gastrin are amongst the first gastrointestinal hormone discovered. In addition to classical actions (contraction of gallbladder, growth and secretion in the stomach and pancreas), these also act as growth stimulants for gastrointestinal malignancies and cell lines. Growth of these tumours is inhibited by antagonists of the cholecystokinin and gastrin receptors. These receptors provides most promising approach in clinical oncology and several specific radiolabelled ligands have been synthesized for specific tumour targeting and therapy of tumours overexpressing these receptors. Therefore, definition of the molecular structure of the receptor involved in the autocrine/paracrine loop may contribute to novel therapies for gastrointestinal cancer. Hence, this review tries to focus on the role and distribution of these hormones and their receptors in gastrointestinal cancer with a brief talk about the clinical trial using available agonist and antagonist in gastrointestinal cancers.

Suppression by verapamil of bombesin-enhanced peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane in wistar rats

BACKGROUND

The effects of combined administration of bombesin and verapamil hydrochloride (verapamil), a calcium channel blocker, on the incidence of peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane (AOM) and the labeling index of intestinal cancers were investigated in male Wistar rats.

METHODS

From the beginning of the experiment, rats were given 10 weekly subcutaneous injections of AOM (7.4 mg/kg body weight) and subcutaneous injections of bombesin (40 microg/kg body weight) every other day, and from week 16, intraperitoneal injections of verapamil (10 or 20 mg/kg body weight) every other day until the end fo the experiment in week 45.

RESULTS

Bombesin significantly increased the incidence of intestinal tumors and cancer metastasis to the peritoneum. Although verapamil administered at either dose had little or no effect on the enhancement of intestinal carcinogenesis by bombesin or on the location, histologic type, depth of involvement, labeling index, apoptotic index or tumor vascularity of intestinal cancers, it significantly decreased the incidence of cancer metastasis. Verapamil also significantly decreased the incidence of lymphatic invasion of adenocarcinomas, which was enhanced by bombesin.

CONCLUSION

These findings indicate that verapamil inhibits cancer metastasis through actions that do not affect the growth of intestinal cancers.

Genistein attenuates peritoneal metastasis of azoxymethane-induced intestinal adenocarcinomas in Wistar rats

The effects of the soybean isoflavonoid genistein on the development of bombesin-enhanced peritoneal metastasis from intestinal adenocarcinomas induced by azoxymethane (AOM) were investigated in male inbred Wistar rats. From the beginning of the experiment, rats were given 10 weekly s.c. injections of AOM (7.4 mg/kg body weight) and s.c. injections of bombesin (40 microg/kg body weight) every other day, and from week 16, s.c. injections of genistein (5 or 10 mg/kg body weight) every other day until the end of the experiment in week 45. Bombesin significantly increased the incidence of intestinal tumors and of cancer metastasis to the peritoneum. Although genistein administered at either dose had little or no effect on the enhancement of intestinal carcinogenesis by bombesin or on the location, histologic type, depth of involvement, labeling index, or growth pattern of intestinal cancers, it significantly decreased the incidence of cancer metastasis. Genistein also significantly decreased the incidence of lymphatic vessel invasion of adenocarcinomas, which was enhanced by bombesin. Our findings indicate that genistein attenuates cancer metastasis by inhibiting cancer cell invasion into lymphatic vessels through activities that do not affect the growth of intestinal cancers.

Peptide YY inhibits growth of human breast cancer in vitro and in vivo

BACKGROUND

Hormonal manipulation is important in the treatment of breast cancer. Gastrointestinal hormones may have antiproliferative effects on malignancies arising outside the gastrointestinal tract. Peptide YY (PYY) suppresses growth of, and levels of, intracellular cyclic adenosine monophosphate (cAMP) in pancreatic adenocarcinoma. We hypothesized that PYY would inhibit growth of breast cancer.

MATERIALS AND METHODS

MCF-7 human breast infiltrative ductal carcinoma cells in 96-well plates were treated with PYY at 1.25 pmol/mcl. Control wells received an equal volume of bovine serum albumin to mimic experimental conditions. In vitro survival was determined by MTT assays, which reflect cell viability by measuring mitochondrial NADH-dependent dehydrogenase activity. MCF-7 cells in six-well plates were treated with PYY or albumin as described above. Intracellular cAMP levels in cell lysates were determined with a tritiated cAMP assay. One million MCF-7 cells were injected into mammary fat pads of 20 female athymic nude mice. Pellets releasing PYY at 400 pmol/kg/h were placed subcutaneously in 10 mice 24 h prior to cell inoculation. Tumors were harvested after 21 days, weighed, and measured with vernier calipers.

RESULTS

PYY reduced in vitro growth by 40% (P < 0.001). Intracellular cAMP levels in PYY-treated cells were 62.4% less than those of controls (P < 0.001). Tumors from control mice weighed twice as much as those from PYY-treated mice (P < 0.006); volume of PYY-exposed tumors was one-third that of controls (P < 0.005).

CONCLUSIONS

PYY inhibits growth of breast cancer in vitro and in vivo and may be of benefit in the treatment of this malignancy. The reduction in intracellular cAMP levels may contribute to the observed suppression of cell proliferation.

Inhibition by ginsenoside Rg3 of bombesin-enhanced peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane in Wistar rats

The effects of concomitant use of bombesin and ginsenoside Rg3 on the incidence of peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane were investigated in male inbred Wistar rats. From the start of the experiment, rats were given weekly s.c. injections of azoxymethane (7.4 mg/kg body weight) for 10 weeks and s.c. injection of bombesin (40 microg/kg body weight) every other day, and from week 20, s.c. injections of ginsenoside Rg3 (2.5 or 5.0 mg/kg body weight) every other day until the end of the experiment in week 45. Bombesin significantly increased the incidence of intestinal tumors and cancer metastasis to the peritoneum in week 45. It also significantly increased the labeling index of intestinal cancers. Although administration of a higher dose of ginsenoside Rg3 with bombesin had little or no effect on the enhancement of intestinal carcinogenesis by bombesin, the location, histologic type, depth of involvement, infiltrating growth pattern, labeling and apoptotic indices and tumor vascularity of intestinal cancers, it significantly decreased the incidence of cancer metastasis. These findings indicate that ginsenoside Rg3 inhibits cancer metastasis through activities that do not affect the growth or vascularity of intestinal cancers.

Triamterene suppresses bombesin-enhanced peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane

The effects of combined administration of bombesin and the diuretic triamterene on the incidence of peritoneal metastasis of intestinal cancers induced by azoxymethane (AOM) and the labeling index of intestinal cancers were investigated in male inbred Wistar rats. From the start of the experiment, rats were given weekly s.c. injections of AOM (7.4 mg/kg body weight) for 10 weeks and s.c. injections of bombesin (40 micrograms/kg body weight) every other day, and from week 16, s.c. injections of triamterene (10 and 20 mg/kg body weight) every other day until the end of the experiment in week 45. Bombesin significantly increased the incidence of intestinal tumors and cancer metastasis to the peritoneum in week 45. It also significantly increased the labeling index of intestinal cancers. Although administration of both doses of triamterene with bombesin had little or no influence on the enhancement of intestinal carcinogenesis by bombesin, or the location, histologic type, depth of invasion, or labeling index of intestinal cancers, it significantly reduced the incidence of cancer metastasis. These findings indicate that triamterene suppresses cancer metastasis through a mechanism that does not affect the proliferation of intestinal cancers.