Long non-coding RNAs are emerging targets of phytochemicals for cancer and other chronic diseases.

The long non-coding RNAs (lncRNAs) are the crucial regulators of human chronic diseases. Therefore, approaches such as antisense oligonucleotides, RNAi technology, and small molecule inhibitors have been used for the therapeutic targeting of lncRNAs. During the last decade, phytochemicals and nutraceuticals have been explored for their potential against lncRNAs. The common lncRNAs known to be modulated by phytochemicals include ROR, PVT1, HOTAIR, MALAT1, H19, MEG3, PCAT29, PANDAR, NEAT1, and GAS5. The phytochemicals such as curcumin, resveratrol, sulforaphane, berberine, EGCG, and gambogic acid have been examined against lncRNAs. In some cases, formulation of phytochemicals has also been used. The disease models where phytochemicals have been demonstrated to modulate lncRNAs expression include cancer, rheumatoid arthritis, osteoarthritis, and nonalcoholic fatty liver disease. The regulation of lncRNAs by phytochemicals can affect multi-steps of tumor development. When administered in combination with the conventional drugs, phytochemicals can also produce synergistic effects on lncRNAs leading to the sensitization of cancer cells. Phytochemicals target lncRNAs either directly or indirectly by affecting a wide variety of upstream molecules. However, the potential of phytochemicals against lncRNAs has been demonstrated mostly by preclinical studies in cancer models. How the modulation of lncRNAs by phytochemicals produce therapeutic effects on cancer and other chronic diseases is discussed in this review.

Molecular targets and anti-cancer potential of escin.

Escin is a mixture of triterpenoid saponins extracted from the horse chestnut tree, Aesculus hippocastanum. Its potent anti-inflammatory and anti-odematous properties makes it a choice of therapy against chronic venous insufficiency and odema. More recently, escin is being actively investigated for its potential activity against diverse cancers. It exhibits anti-cancer effects in many cancer cell models including lung adenocarcinoma, hepatocellular carcinoma and leukemia. Escin also attenuates tumor growth and metastases in various in vivo models. Importantly, escin augments the effects of existing chemotherapeutic drugs, thereby supporting the role of escin as an adjunct or alternative anti-cancer therapy. The beneficial effects of escin can be attributed to its inhibition of proliferation and induction of cell cycle arrest. By regulating transcription factors/growth factors mediated oncogenic pathways, escin also potentially mitigates chronic inflammatory processes that are linked to cancer survival and resistance. This review provides a comprehensive overview of the current knowledge of escin and its potential as an anti-cancer therapy through its anti-proliferative, pro-apoptotic, and anti-inflammatory effects.

Metronomic vinorelbine (oral) in combination with sorafenib in advanced non-small cell lung cancer.

BACKGROUND: To date, biomarkers to predict benefit from anti-angiogenic therapy are still lacking. Sorafenib and metronomic oral vinorelbine combination was studied and changes in blood and DCE-MRI parameters were investigated as biomarkers for benefit. MATERIAL AND METHODS: Patients with advanced NSCLC were recruited to 3 successive cohorts. Each cohort was given a fixed metronomic (3 times a week) dose of oral vinorelbine at 60 mg/week, 90 mg/week, or 120 mg/week respectively. Within each cohort, patients received a starting dose of sorafenib at 200mg bid for 4 weeks. In the absence of dose-limiting toxicities, each patient's dose of sorafenib was escalated to 400mg bid for 4 weeks, 600 mg bid for 4 weeks and finally 800 mg bid. Biomarkers measured include DCE-MRI parameters, circulating endothelial cells (CECs), circulating endothelial progenitor cells (CEPs), and plasma thrombospondin (TSP-1). RESULTS: 48 evaluable patients were analyzed. There were 4 (8.9%) patients with partial response (PR) and 7 (15.2%) with cavitary response (CaR). Two subpopulations of CECs (CEC(hi), CEC(lo)) were identified that trended in opposite directions during treatment, with CEC(hi) demonstrating an upward trend in contrast to CEC(lo). Higher baseline CEC(hi) and lower baseline blood flow (F) and fractional intravascular blood volume (V1) predicted for response. Multivariate analysis revealed a lower baseline V1, and dynamic changes of CEC during treatment (CEC increase, sum of CEC(hi) and CEC(lo)) predicted for improved survival. CONCLUSIONS: Sorafenib and metronomic oral vinorelbine is active in advanced NSCLC. Baseline levels and changes in DCE parameters and CEC may be useful predictive biomarkers.

Garcinol sensitizes human head and neck carcinoma to cisplatin in a xenograft mouse model despite downregulation of proliferative biomarkers.

Platinum compounds such as cisplatin and carboplatin are frequently used as the first-line chemotherapy for the treatment of the head and neck squamous cell carcinoma (HNSCC). In the present study, we investigated whether garcinol, a polyisoprenylated benzophenone can chemosensitize HNSCC to cisplatin. We found that garcinol inhibited the viability of a panel of diverse HNSCC cell lines, enhanced the apoptotic effect of cisplatin, suppressed constitutive as well as cisplatin-induced NF-κB activation, and downregulated the expression of various oncogenic gene products (cyclin D1, Bcl-2, survivin and VEGF). In vivo study showed that administration of garcinol alone (0.5 mg/kg body weight, i.p. five times/week) significantly suppressed the growth of the tumor, and this effect was further increased by cisplatin. Both the markers of proliferation index (Ki-67) and microvessel density (CD31) were downregulated in tumor tissues by the combination of cisplatin and garcinol. The pharmacokinetic results of garcinol indicated that good systemic exposure was achievable after i.p. administration of garcinol at 0.5 mg/kg and 2 mg/kg with mean peak concentration (Cmax) of 1825.4 and 6635.7 nM in the mouse serum, respectively. Overall, our results suggest that garcinol can indeed potentiate the effects of cisplatin by negative regulation of various inflammatory and proliferative biomarkers.

Paracrine factors of human fetal MSCs inhibit liver cancer growth through reduced activation of IGF-1R/PI3K/Akt signaling.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death in the world. The multikinase inhibitor sorafenib only demonstrated marginal improvement in overall survival for advanced disease prompted the search for alternative treatment options. Human mesenchymal stem cells (MSCs) have the ability to home to tumor cells. However, its functional roles on the tumor microenvironment remain controversial. Herein, we showed that conditioned media derived from human fetal MSC (CM-hfMSCs) expressed high level of the insulin growth factor binding proteins IGFBPs and can sequester free insulin-like growth factors (IGFs) to inhibit HCC cell proliferation. The inhibitory effect of IGFBPs on IGF signaling was further evident from the reduction of activated IGF-1R and PI3K/Akt, leading eventually to the induction of cell cycle arrest. We also demonstrated that CM-hfMSCs could enhance the therapeutic efficacy of sorafenib and sunitinib. To the best of our knowledge, this is the first report to show that CM-hfMSCs has a tumor-specific, antiproliferative effect that is not observed with normal human hepatocyte cells and patient-derived matched normal tissues. Our results thus suggest that CM-hfMSCs can provide a useful tool to design alternative/adjuvant treatment strategies for HCC, especially in related function to potentiate the effects of chemotherapeutic drugs.

pH-sensitive nanoformulated triptolide as a targeted therapeutic strategy for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) has one of the worst prognoses for survival as it is poorly responsive to both conventional chemotherapy and mechanism-directed therapy. This results from a lack of therapeutic concentration in the tumor tissue coupled with the highly toxic off-site effects exhibited by these compounds. Consequently, we believe the best packaging for holistic therapy for HCC will involve three components: a potent therapeutic, a rationally designed drug delivery vehicle to enrich the target site concentration of the drug, and a surface ligand that can enable a greater propensity to internalization by tumor cells compared to the parenchyma. We screened a library containing hundreds of compounds against a panel of HCC cells and found the natural product, triptolide, to be more effective than sorafenib, doxorubicin, and daunorubicin, which are the current standards of therapy. However, the potential clinical application of triptolide is limited due to its poor solubility and high toxicity. Consequently, we synthesized tumor pH-sensitive nanoformulated triptolide coated with folate for use in an HCC-subpopulation that overexpresses the folate receptor. Our results show triptolide itself can prevent disease progression, but at the cost of significant toxicity. Conversely, our pH-sensitive nanoformulated triptolide facilitates uptake into the tumor, and specifically tumor cells, leading to a further increase in efficacy while mitigating systemic toxicity.