Proteins govern most biological processes and functions. Recently, much attention has been paid to study the entire protein sets available in a cell. The term , a portmanteau of protein and genome, was coined by Marc Wilkins in 1994 and broadly defined as the total set of proteins that could be expressed in a sample or organism at a given time or the set of proteins that can be detected by some method. This varies with time and distinct requirements, or stresses.

As an interdisciplinary field, bioinformatics combines computer science, statistics and life sciences together, to develop algorithms and professional software tools for mining and interpreting the tremendous biological data, generated in recent booming high throughput -omics studies.

Halogenated nucleotides such as the pyrimidine analog bromodeoxyuridine (BrdU) can be used to label nascent DNA in viable cells. During the process of DNA replication, BrdU can replace thymidine and incorporate into the synthesized DNA of actively dividing cells. Since this BrdU reagent does not cross react with endogenous DNA, cell proliferation thus can be reflected in the extent of BrdU incorporation by determining the intensity of absorbance of the final reaction. The BrdU cell proliferation assay is a versatile and convenient method to quantify cell proliferation.

Cell proliferation assay plays a significant role in cytotoxicity and many other areas of cell biology. A number of methods have been developed for the determination of cell proliferation. Since Fluorescent Cell Proliferation Assay enables accurate counts of cells for a wide range of cell concentrations and experimental conditions, this assay have been the most widely used in the quantification of cell proliferation among all of these methods. High throughput screening and high sensitivity can also be achieved in the study of cell proliferation.

Cell proliferation is a vital indicator to understand the mechanisms in action of certain genes, proteins and pathways that involve in cell survival or death. Furthermore, cell proliferation plays an important role in regulating the development of bodies and organs, especially in all multicellular organisms. If cells proliferate unsystematically, bodies or organs would become mere cell masses and proper cell proliferation is essential for maintenance of sizes, morphology and functions of organs.

The research of the interaction and invasion behavior plays a crucial role in the studies of the mechanisms of cell invasion which is significant in malignant metastasis of cancer. Both the determination of the interaction and invasion behavior can be achieved with the spheroid confrontation assay.

In experimental cellular biology, invasion is defined as disruptive, proteolytic, cellular movement through three-dimensional barriers. Despite intense study, the complex and heterogenous mechanisms of invasion and metastasis remain imperfectly understood and several mechanisms exist in collective or individual invasion of cancer cells. Thus, there is a need to establish robust, reproducible assays to target the process and get a detailed analysis of invasion. The three-dimensional (3D) spheroid invasion assay is a simple and convenient method to research cell invasion, which is based on the uniform and self-assembling 3D tumor spheroids.

Anthocyanins belong to the flavonoids class of the polyphenol. They are contributing to the colors such as red, blue, yellow and purple of many fruits and vegetables. In nature, anthocyanins predominantly exist as glycosides of polymethoxy and polyhydroxy derivatives of flavylium salts or 2-phenyl-benzopyryliurn.

The amino acid 2,6-diaminopimelic acid (DAPA) is a unique component in bacterial cell walls, thus it can be used as an indirect and specific indicator for the measurement of bacterial mass content in such biological materials as feeds or digestive tract contents in ruminants.

For instance, this measure can provide the predictive power when an environmental pollutant experiences different biodegradation rates or pathways in aerobic environments and anaerobic environments.