The novel quinolizidine derivate IMB-HDC inhibits STAT5a phosphorylation at 694 and 780 and promotes DNA breakage and cell apoptosis via blocking STAT5a nuclear translocation

In vivo targeting of a tumor-antigen encoded DNA vaccine to dendritic cells in combination with tumor-selective chemotherapy eradicates established mouse melanoma

Despite remarkable progress during the past decade, eradication of established tumors by targeted cancer therapy and cancer immunotherapy remains an uphill task. Herein, we report on a combination approach for eradicating established mouse melanoma. Our approach employs the use of tumor selective chemotherapy in combination with in vivo dendritic cell (DC) targeted DNA vaccination. Liposomes of a newly synthesized lipopeptide containing a previously reported tumor-targeting CGKRK-ligand covalently grafted in its polar head-group region were used for tumor selective delivery of cancer therapeutics. Liposomally co-loaded STAT3siRNA and WP1066 (a commercially available inhibitor of the JAK2/STAT3 pathway) were used as cancer therapeutics. In vivo targeting of a melanoma antigen (MART-1) encoded DNA vaccine (p-CMV-MART1) to dendritic cells was accomplished by complexing it with a previously reported mannose-receptor selective in vivo DC-targeting liposome. Liposomes of the CGKRK-lipopeptide containing encapsulated FITC-labeled siRNA, upon intravenous administration in B16F10 melanoma bearing mice, showed remarkably higher accumulation in tumors 24 h post i.v. treatment, compared to their degree of accumulation in other body tissues including the lungs, liver, kidneys, spleen and heart. Importantly, the findings in tumor growth inhibition studies revealed that only in vivo DC-targeted genetic immunization or only tumor-selective chemotherapy using the presently described systems failed to eradicate the established mouse melanoma. The presently described combination approach is expected to find future applications in combating various malignancies (with well-defined surface antigens).

SALIS transcriptionally represses IGFBP3/Caspase-7-mediated apoptosis by associating with STAT5A to promote hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common subtype of liver cancer and the second most fatal cancer in the world despite the great therapeutic advances in the past two decades, which reminds us of the gap in fully understanding the oncogenic mechanism of HCC. To explore the key factors contributing to the progression of HCC, we identified a LncRNA, termed SALIS (Suppression of Apoptosis by LINC01186 Interacting with STAT5A), functions in promoting the proliferation, colony formation, migration and invasion while suppressing apoptosis in HCC cells. Mechanistic study indicated SALIS physically associates with transcription factor STAT5A and binds to the promoter regions of IGFBP3 and Caspase-7 to transcriptionally repress their expression and further inhibit apoptosis. Our findings identified SALIS as an oncogene to promote HCC by physically binding with STAT5A to inhibit the expression of pro-apoptotic IGFBP3 and Caspase-7, which suggests novel therapeutic targets for HCC treatments.

Research Progress in the Pharmacological Activities, Toxicities, and Pharmacokinetics of Sophoridine and Its Derivatives

Sophoridine is a natural quinolizidine alkaloid and a bioactive ingredient that can be isolated and identified from certain herbs, including Sophora flavescens Alt, Sophora alopecuroides L, and Sophora viciifolia Hance. In recent years, this quinolizidine alkaloid has gained widespread attention because of its unique structure and minimal side effects. Modern pharmacological investigations have uncovered sophoridine's multiple wide range biological activities, such as anti-cancer, anti-inflammatory, anti-viral, anti-arrhythmia, and analgesic functions, among others. These pharmacological activities and beneficial effects point to sophoridine as a strong potential therapeutic candidate for the treatment of various diseases, including several cancer types, hepatitis B virus, enterovirus 71, coxsackievirus B3, cerebral edema, cancer pain, heart failure, acute myocardial ischemia, arrhythmia, inflammation, acute lung injury, and osteoporosis. The data showed that sophoridine had adverse reactions, including hepatotoxicity and neurotoxicity. Additionally, analyses of sophoridine's safety, bioavailability, and pharmacokinetic parameters in animal models of research have been limited, especially in the clinic, as have been investigations on its structure-activity relationship. In this article, we comprehensively summarize the biological activities, toxicity, and pharmacokinetic characteristics of sophoridine and its derivatives, as currently reported in publications, as we attempt to provide an overall perspective on sophoridine analogs and the prospects of its application clinically.

Tumor microenvironment: a prospective target of natural alkaloids for cancer treatment

Malignant tumor has become one of the major diseases that seriously endangers human health. Numerous studies have demonstrated that tumor microenvironment (TME) is closely associated with patient prognosis. Tumor growth and progression are strongly dependent on its surrounding tumor microenvironment, because the optimal conditions originated from stromal elements are required for cancer cell proliferation, invasion, metastasis and drug resistance. The tumor microenvironment is an environment rich in immune/inflammatory cells and accompanied by a continuous, gradient of hypoxia and pH. Overcoming immunosuppressive environment and boosting anti-tumor immunity may be the key to the prevention and treatment of cancer. Most traditional Chinese medicine have been proved to have good anti-tumor activity, and they have the advantages of better therapeutic effect and few side effects in the treatment of malignant tumors. An increasing number of studies are giving evidence that alkaloids extracted from traditional Chinese medicine possess a significant anticancer efficiency via regulating a variety of tumor-related genes, pathways and other mechanisms. This paper reviews the anti-tumor effect of alkaloids targeting tumor microenvironment, and further reveals its anti-tumor mechanism through the effects of alkaloids on different components in tumor microenvironment.