ProstaCaid inhibits tumor growth in a xenograft model of human prostate cancer

Comprehensive characterization of chemotherapeutic efficacy on metastases in the established gastric neuroendocrine cancer patient derived xenograft model

The HuPrime^® human gastric neuroendocrine carcinoma derived xenograft model GA0087 was established in this study. GA0087 PDX model showed high gene expression of vascular endothelial growth factors (VEGF)-A and B, and high potential of lung metastasis. Circulating tumor cells (CTCs) with either large or small size, circulating tumor microemboli (CTM) and lung metastatic lesions were detected in GA0087 PDX mice. The number of CTC correlated to the number of metastatic nodules in lung. Both primary tumor growth and metastasis in terms of the number of dynamically monitored CTCs and metastatic nodules were effectively suppressed by Cisplatin. Diverse subtypes of CTCs in the context of sensitivity to Cisplatin were specifically identified by subtraction enrichment (SE) integrated with in situ Phenotyping of cytokeratin 18 (CK18) and Karyotyping of chromosome 8 (in situ PK CTC by CK-iFISH). All the CK18-/diploid and majority of CK18+/diploid CTC subtypes were chemosensitive, whereas a higher percentage of CK18+/multiploid subtype of CTC were Cisplatin-insensitive. Combined histopathological examination of metastatic lesion and in situ PK CTC in a metastatic PDX (mPDX) tumor model are of particular significance, and may provide an unique and robust platform for cancer research as well as pre-clinical evaluation of therapeutic efficacy of new anti-cancer drugs.

Thermally targeted p21 peptide enhances bortezomib cytotoxicity in androgen-independent prostate cancer cell lines

Prostate cancer remains one of the most common malignancies in men. Besides surgical resection, treatments for prostate cancer include hormone therapy, chemotherapy, and radiation therapy. Advancement of prostate cancer to an androgen-independent state limits the potential of conventional therapeutic approaches. Bortezomib, an FDA-approved proteosomal inhibitor for the treatment of myeloid leukemia, has been shown to have a positive effect on the inhibition of prostate cancer growth. Unfortunately, bortezomib has a very narrow therapeutic window, which can lead to severe side effects. Elastin-like polypeptide (ELP) is a genetically engineered, thermally responsive macromolecular carrier that enables a targeted delivery of the bound molecule because of its soluble property under normal physiologic conditions. In addition, ELP aggregates in response to mild hyperthermia. Using ELP as a carrier, it is possible to improve the pharmacological properties of the therapeutic drug as well as reduce toxicity in normal tissues. In this work, we have investigated the combination treatment of androgen-independent prostate cancer cells with bortezomib and the C-terminal part of the p21(WAF1/CIP1) protein bound to the ELP carrier. We have found that combination treatment with bortezomib and ELP-bound p21(WAF1/CIP1) protein leads to increased cell cycle arrest as well as apoptosis with respect to single treatments. We believe that this approach represents a promising direction for the treatment of androgen-independent prostate cancer.

Resveratrol-based combinatorial strategies for cancer management

In recent years combination chemoprevention has been increasingly appreciated and investigated as a viable and effective strategy for cancer management. A plethora of evidence suggests that a combination of agents may afford synergistic (or additive) advantage for cancer management by multiple means, such as by (1) enhancing the bio-availability of chemopreventive agents, (2) modifying different molecular targets, and (3) lowering the effective dose of agent/drug to be used for cancer management. Resveratrol has been shown to afford chemopreventive and therapeutic effects against certain cancers. Recent studies are suggesting that resveratrol may be very useful when given in combination with other agents. The two major advantages of using resveratrol in combination with other agents are synergistically or additively enhancing the efficacy against cancer and limiting the toxicity and side effects of existing therapies. However, concerted and multidisciplinary efforts are needed to identify the most optimal combinatorial strategies.