Biopolymers as potential carrier for effervescent reaction based drug delivery system in gastrointestinal condition

Biopolymers are naturally occurring materials formed in nature during the life cycles of organisms. Biopolymers include the polysaccharides, carbohydrates and protein such as cellulose, starch, wool, silk, gelatine and collagen. In recent years, biopolymer-based hydrogels become important area of research in pharmaceutical aspects because of their promising properties in drug delivery system. These properties include low toxicity, biodegradability, stability and renewable nature. Numerous studies have been carried out in order to develop carrier from biopolymers with better controlled release properties. This is important to ensure precisely desired concentration of drug or essential nutrient absorption into the blood or tissue could be achieved. Among other different approaches, floating system is one of the most convenient, economical, and effective drug delivery system. Floating delivery system could potentially achieve longer retention time of carrier with capsulated bioactive drug or functional nutrients in the gastrointestinal tract. The floating behaviour of carrier could be induced by effervescent reactions. Effervescent reaction occurs between acidic gastric content and pore forming agent such as carbonates or bicarbonates salts incorporated into the carrier. This chapter discusses some of the use of biopolymers in drug delivery systems for effervescent reaction in gastrointestinal tract

New targets for the immunotherapy of colon cancer—does reactive disease hold the answer?

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers in both men and women, posing a serious demographic and economic burden worldwide. In the United Kingdom, CRC affects 1 in every 20 people and it is often detected once well established and after it has spread beyond the bowel (Stage IIA-C and Stage IIIA-C). A diagnosis at such advanced stages is associated with poor treatment response and survival. However, studies have identified two sub-groups of post-treatment CRC patients--those with good outcome (reactive disease) and those with poor outcome (non-reactive disease). We aim to review the state-of-the-art for CRC with respect to the expression of cancer-testis antigens (CTAs) and their identification, evaluation and correlation with disease progression, treatment response and survival. We will also discuss the relationship between CTA expression and regulatory T-cell (Treg) activity to tumorigenesis and tumor immune evasion in CRC and how this could account for the clinical presentation of CRC. Understanding the molecular basis of reactive CRC may help us identify more potent novel immunotherapeutic targets to aid the effective treatment of this disease. In this review, based on our presentation at the 2012 International Society for the Cell and Gene Therapy of Cancer annual meeting, we will summarize some of the most current advances in CTA and CRC research and their influence on the development of novel immunotherapeutic approaches for this common and at times difficult to treat disease