Inhibition of human pancreatic cell line MIA PaCa2 proliferation by HA-But, a hyaluronic butyric ester: a preliminary report.

OBJECTIVES: Inhibition of histone deacetylase activity is one of the epigenetic mechanisms in the regulation of the cellular gene expression. We investigated the antitumor effect of HA-But, a new histone deacetylase inhibitor, in which hyaluronic acid is esterified with butyric acid residues and selectively bind to CD44, overexpressed in most human cancers, including pancreatic cancer. METHODS: We analyzed the effect of HA-But on the expression level of some cell cycle (p21 waf1/cip1, p27 kip1, p53, and cyclin D1), apoptosis (BAX, caspase-7, Bcl-2, and survivin), and angiogenesis-related (vascular endothelial growth factor [VEGF] A165, VEGF-C, and VEGF-D) proteins on MIA PaCa-2, a pancreas carcinoma cell line that expressed CD44 in a high percentage (99%) of cells. RESULTS: HA-But was 7-fold more effective than sodium butyrate in inhibiting cell proliferation; it induced p21 waf1/cip1, p27 kip1, p53, and cyclin D1 modulation, resulting in a block of the cell cycle at G0/G1 and G2/M phases. Moreover, Ha-But induced apoptosis, affecting the expression level of either proapoptotic or antiapoptotic factors, reduced the expression level of VEGF-A165 and VEGF-D, and inhibited the angiogenesis process in vitro. CONCLUSIONS: On the basis of these results, which demonstrated an interesting antiproliferative, proapoptotic, and antiangiogenic activity, Ha-But could be a promising candidate for the treatment of pancreatic cancer.

Hyaluronic acid butyric esters in cancer therapy.

In this review we focus on a promising novel histone deacetylase (HDAC) inhibitor (HA-But) obtained by the esterification of butyric acid (BA), the smallest HDAC inhibitor, with hyaluronic acid (HA), the main constituent of the extracellular matrix which selectively recognizes a transmembrane receptor (CD44) overexpressed in most primary cancers and associated with tumor progression. In vitro, HA-But has proved to be 10-fold more effective than BA in inhibiting the proliferation of a panel of human cancer cell lines, representative of the most common human cancers, and, similar to BA, to regulate the expression of some cell cycle-related proteins, to induce growth arrest in the G1/G0 phase of the cell cycle and to increase histone acetylation. In vivo, HA-But treatment has demonstrated a marked potency in inhibiting primary tumor growth and lung metastases formation from murine Lewis lung carcinoma (LL3) as well as liver metastases formation from intrasplenic implantation of LL3 or B16-F10 murine melanoma cells. In particular, the effect of s.c. and i.p. treatment with HA-But on liver metastases resulted, respectively, in 87 and 100% metastases-free animals, and in a significant prolongation of the survival time compared to the control groups. The results suggest that the presence of the HA backbone does not interfere with the biological activity of butyric residues and that HA-But could represent a promising cell-targetable antineoplastic agent for the treatment of primary and metastatic tumors.

Inhibition of hepatocellular carcinomas in vitro and hepatic metastases in vivo in mice by the histone deacetylase inhibitor HA-But.

PURPOSE: The purpose is to evaluate the CD44-mediated cellular targeting of HA-But, a hyaluronic acid esterified with butyric acid (But) residues, to hepatocellular carcinoma cell lines in vitro and to hepatic tumor metastases in vivo. EXPERIMENTAL DESIGN: In vitro, the CD44-dependent cytotoxicity in two human hepatocellular carcinoma cell lines (HepB3 and HepG2) with high and low CD44 expression was investigated; in vivo, the effect on liver metastases originating from intrasplenic implants of Lewis lung carcinoma (LL3) or B16-F10 melanoma in mice was compared with the pharmacokinetics of organ and tissue distribution using different routes of administration. RESULTS: HepB3 and HepG2 cell lines showed different expression of CD44 (78 and 18%, respectively), which resulted in a CD44-dependent HA-But inhibitory effect as demonstrated also by the uptake analysis performed using radiolabeled HA-But ((99m)Tc-HA-But). Pharmacokinetic studies showed different rates of (99m)Tc-HA-But distribution according to the route of administration (i.v., i.p., or s.c.): very fast (a few minutes) after i.v. treatment, with substantial accumulation in the liver and spleen; relatively slow after i.p. or s.c. treatment, with marked persistence of the drug at the site of injection. The effect of s.c. and i.p. treatment with HA-But on liver metastases originating from intrasplenic implants of LL3 carcinoma or B16-F10 melanoma (both CD44-positive: 68 and 87%, respectively), resulted in 87 and 100% metastases-free animals, respectively (regardless of the route of administration), and a significant prolongation of the life expectancy compared with control groups. CONCLUSIONS: HA-But tends to concentrate in the liver and spleen and appears to be a promising new drug for the treatment of intrahepatic tumor lesions.

Hyaluronic-acid butyric esters as promising antineoplastic agents in human lung carcinoma: a preclinical study.

New promising compounds, derived from the esterification of hyaluronic acid with butyric acid, were investigated in vitro on a non-small cell lung carcinoma cell line (NCI-H460) and an its metastatic subclone (NCI-H460M). All new compounds exerted a dose-dependent inhibitory effect on both cell lines, which expressed CD44, the specific surface receptor for hyaluronic acid, in a very high percentage of cells (90%). HE1, the most effective of these compounds, was 10-fold more effective than sodium butyrate (NaB) in inhibiting cell proliferation. Similarly to NaB, after 24 hours of treatment, HE1 affected the expression of three cell cycle-related proteins (p27(kip1), p53 and p21(waf1)) responsible for growth arrest, indicating that the presence of the hyaluronic acid backbone does not interfere with the biologic activity. Intratumoral treatment with HE1 demonstrated a marked efficacy on primary tumor growth and on lung metastases formation of the murine Lewis Lung Carcinoma model. Altogether, present findings suggest a possible clinical application of these novel butyric pro-drugs in primary and metastatic lung cancer.

Modulation of angiogenesis-related proteins synthesis by sodium butyrate in colon cancer cell line HT29.

Sodium butyrate (NaB), a short-chain fatty acid naturally present in the human colon, is able to induce cell cycle arrest, differentiation and apoptosis in colon cancer cells. In addition to these effects, we investigated the effect of NaB on two angiogenesis-related proteins in a colon carcinoma cell line (HT29): vascular endothelial growth factor (VEGF), the most potent angiogenic factor, and hypoxia-inducible factor (HIF)-1alpha, the main transcription activator of the VEGF gene, which are both constitutively expressed at high levels in HT29 also in normoxic conditions. NaB treatment had a different effect on VEGF165 and HIF-1alpha expression. In fact, it induced a dose-dependent down regulation of the VEGF165 protein level that was not paralleled by a concomitant down regulation of the corresponding mRNA, suggesting a post-translational regulation of the factor. Conversely, after 24 h of treatment all the tested NaB concentrations reduced the HIF-1alpha protein level, whereas after a longer time of exposure HIF-1alpha level increased in the presence of a high NaB concentration (2 mM) with a concomitant increase in HIF-1alpha mRNA. These results indicate that NaB, besides regulating other fundamental cellular processes, is able to modulate the expression of two important angiogenesis-related molecules and suggested a further possible clinical application of this short-chain fatty acid as an anti-angiogenic compound in association with conventional chemotherapeutic agents.