Repair

DNA is prone to numerous forms of damage that can injure cells and impair fitness. Cells have developed an array of mechanisms to repair these injuries. Proliferating cells are especially vulnerable to DNA damage due to the added demands of cellular growth and division. Cell cycle checkpoints represent integral components of DNA repair that coordinate cooperation between the machinery of the cell cycle and several biochemical pathways that respond to damage and restore DNA structure. By delaying progression through the cell cycle, checkpoints provide more time for repair before the critical phases of DNA replication, when the genome is replicated, and of mitosis, when the genome is segregated. Loss or attenuation of checkpoint function may increase spontaneous and induced gene mutations and chromosomal aberrations by reducing the efficiency of DNA repair.

MCE owns a unique collection of 3,313 cell cycle/DNA damage-related compounds which can be used in the research of the same.

In this era of rapid advancement in gene-editing technology, the CRISPR-Cas system, with its powerful programmability, is leading a transformation in life sciences research. It enables efficient and precise targeted modification of an organism's genome, providing a robust tool for studying gene function, treating genetic diseases, and improving crop varieties. However, bottlenecks such as insufficient editing efficiency, low homologous directed repair efficiency, and potential off-target risks remain major challenges in achieving precise genetic modifications and developing gene therapies.

To overcome these limitations, the MCE High-Efficiency Gene Editing Compound Library systematically includes 730 small molecules that are known or have the potential to enhance gene-editing efficiency. These compounds work by targeting and modulating the DNA damage repair network, mechanistically inhibiting non-homologous end joining, promoting homologous directed repair, or regulating chromatin states and cellular responses, thereby significantly optimizing editing outcomes. This library is suitable for developing "CRISPR-small molecule" combination therapy strategies, improving gene-editing efficiency, and providing a powerful tool for in-depth research into the mechanisms of DNA damage repair in gene editing.

Neuropeptides are small proteins produced and released by neurons through the regulation of secretory pathways, expressed in neurons and have transmitter or co-transmitter functions, and are used as nerve substrates. Neuropeptides are by far the largest and most diverse signaling molecules in the brain and have been implicated in the development of diseases and drugs. Neuropeptides are involved in inflammatory and immune diseases and have an impact on epithelial, vascular, and connective tissue cells proliferation and tissue repair. Studies have shown that neuropeptides are particularly important when the nervous system is challenged, such as stress, injury, or substance abuse. Substance P is a neuropeptide that acts as a neurotransmitter and neuromodulator in the central nervous system and is currently in clinical research and has been shown to be involved in inflammatory processes and pain.

MCE can provide 126 neuropeptides that can be used for scientific research.

Antibiotics are types of antimicrobial products used for the treatment and prevention of bacterial infections. Antibiotics can kill or inhibit bacterial growth. Although the target of an antibiotic is bacteria, some antibiotics also attack fungi and protozoans. However, antibiotics rarely have an effect on viruses. The major mechanism underlying antibiotics is the inhibition or regulation of enzymes involved in cell wall biosynthesis, nucleic acid metabolism and repair, protein synthesis, or disruption of membrane structure. Many of these cellular functions targeted by antibiotics are most active in multiplying cells. Since there is often overlap in these functions between prokaryotic bacterial cells and eukaryotic mammalian cells, it is not surprising that some antibiotics have also been found to be useful as anticancer agents.

MCE supplies a unique collection of 752 antibiotics, including penicillins, cephalosporins, tetracyclines, macrolides, etc. MCE Antibiotics Library is a useful tool for anti-bacterial or anti-cancer drugs discovery.

Fibrosis is a kind of repair response to long-term tissue damage, which is mainly manifested by excessive deposition of extracellular matrix (ECM) and scar formation. Myofibroblasts are the main generating cells of extracellular matrix, and their activation process is related to various pathological mechanisms including Oxidative stress, chronic inflammation and cytokine secretion. Fibrosis can occur in many organs, such as kidneys, liver, heart, lungs, etc. Continuous fibrosis can lead to the destruction of the normal structure of tissues and organs, and if not controlled in time, may cause organ failure or even life-threatening.

MCE contains 2,415 compounds targeting ant-fibrosis targets such as TGF-β, PI3K, Wnt, MMP, etc. These compounds have clear or potential anti-fibrosis activity and can be used for mechanism research and drug screening of fibrosis diseases.

Cell death is a core biological process that maintains homeostasis in multicellular organisms, playing a dual role in life activities. On one hand, cell death participates in physiological processes such as cell renewal and damage repair through precise regulation; on the other hand, it actively eliminates damaged, infected, or cancerous cells, thereby blocking pathological progression and preserving organism health. Cell death not only ensures the normal development and growth regulation of organisms but is also closely associated with the occurrence and development of various diseases. Numerous studies have shown that specific types of programmed cell death play critical roles in disease progression, providing an important theoretical basis for developing novel therapeutic strategies by regulating cell death pathways.

MCE offers 22 types of commonly used cell death inhibitors, such as apoptosis, ferroptosis, pyroptosis, and cuproptosis, suitable for use as positive controls in the study of novel cell death mechanisms.

Vitamins are a category of trace organic compounds essential for maintaining normal physiological functions in living organisms. They are classified into fat-soluble and water-soluble vitamins. Fat-soluble vitamins play a role in maintaining vision, bone health, reproductive functions, and blood coagulation. Water-soluble vitamins are involved in energy metabolism, nervous system function, and cellular repair processes. Most vitamins cannot be synthesized by the organism and must be obtained through diet. In recent years, vitamins and their derivatives have become increasingly important in the field of drug development due to their extensive physiological activities. Additionally, vitamins and their derivatives can be used to construct research platforms for vitamin metabolism, which helps to delve into the metabolic pathways and dynamic changes of vitamins within the body and aids in identifying new biomarkers for certain diseases.

MCE included 134 vitamins and their derivatives, including Vitamin A, Vitamin B, Vitamin D, etc., which is a good tool for studying vitamin metabolism.

A histone modification, a covalent post-translational modification (PTM) to histone proteins, includes methylation, phosphorylation, acetylation, ubiquitylation, and sumoylation, etc. In general, histone modifications are catalyzed by specific enzymes that act predominantly at the histone N-terminal tails involving amino acids such as lysine or arginine, as well as serine, threonine, tyrosine, etc. The PTMs made to histones can impact gene expression by altering chromatin structure or recruiting histone modifiers. Histone modifications act in diverse biological processes such as transcriptional activation/inactivation, chromosome packaging, and DNA damage/repair. Deregulation of histone modification contributes to many diseases, including cancer and autoimmune diseases.

MCE owns a unique collection of 904 bioactive compounds targeting Epigenetic Reader Domain, HDAC, Histone Acetyltransferase, Histone Demethylase, Histone Methyltransferase, Sirtuin, etc. Histone Modification Research Compound Library is a useful tool for histone modification research and drug screening.

Radiotherapy is a common treatment for various cancers, and more than 50% of cancer patients require radiotherapy during the disease treatment. With advances in radiation technology and a better understanding of tumor biology, the efficacy of radiation therapy has gradually improved, and more and more patients have benefited from it. However, even with the use of advanced radiotherapy techniques, there are still many malignant tumor cells with low sensitivity to radiation, leading to the radiation effect is not ideal. To solve this problem, radiosensitizers have received more and more attention. Radiosensitizer is a kind of drug that can enhance the radiosensitivity of tumor cells and improve the effect of radiotherapy. Radiation sensitizers act in a variety of ways, such as killing hypoxic cells, enhancing DNA damage, inhibiting DNA damage repair, and blocking cell cycle progression, making tumor cells more susceptible to radiation damage and death than surrounding normal cells.

MCE designs a unique collection of 41 compounds with definite reported radiosensitization. It can be used for drug combination research in anti-cancer treatment.

Protein ubiquitination is an enzymatic post-translational modification in which an ubiquitin protein is attached to a substrate protein. Ubiquitination involves three main steps: activation, conjugation, and ligation, performed by ubiquitin-activating enzymes (E1s), ubiquitin-conjugating enzymes (E2s), and ubiquitin ligases (E3s), respectively. Ubiquitination affects cellular processes such as apoptosis, cell cycle, DNA damage repair, and membrane transportation, etc. by regulating the degradation of proteins (via the proteasome and lysosome), altering the cellular localization of proteins, affecting proteins activity, and promoting or preventing protein-protein interactions. Deregulation of ubiquitin pathway leads to many diseases such as neurodegeneration, cancer, infection and immunity, etc.

MCE offers a unique collection of 482 small molecule modulators with biological activity used for ubiquitination research. Compounds in this library target the key enzymes in ubiquitin pathway. MCE Ubiquitination Compound Library is a useful tool for the research of ubiquitination regulation and the corresponding diseases.

Pattern Recognition Receptors (PRRs) are a crucial class of protein molecules expressed in cells of the innate immune system. The core function of Pattern Recognition Receptors is to recognize Pathogen-Associated Molecular Patterns (PAMPs) and Damage-Associated Molecular Patterns (DAMPs). Upon recognizing and binding to PAMPs or DAMPs, PRRs rapidly initiate intracellular signaling pathways (such as the NF-κB, IRF, and inflammasome pathways). This triggers the production of inflammatory factors, chemokines, and type I interferons, thereby initiating inflammatory responses to eliminate pathogens or repair damage. PRRs represent the body's first line of defense against infection, and the rapidity and broad specificity of their response are crucial for host survival. However, aberrant activation of PRR signaling is also a cause of many chronic inflammatory diseases, autoimmune disorders, and neurodegenerative diseases. Therefore, precisely regulating PRR activity has become a key therapeutic strategy for these conditions.

MCE has cataloged 313 inhibitors targeting key PRRs, such as NLRs, TLRs, C-type Lectin Receptors (CLRs), and cGAS, to support drug discovery efforts for chronic inflammatory diseases.

Macrophages are effector cells of the innate immune system, engulfing bacteria and secreting pro-inflammatory and antibacterial mediators. They are an important component of the first line defense against pathogens and tumor cells. In addition, macrophages play an important role in eliminating damaged cells through programmed cell death. Like all immune cells, macrophages originate from pluripotent hematopoietic stem cells in the bone marrow. Macrophages play key functions in many physiological processes beyond homeostasis and innate immunity, including metabolic function, cell debris clearance, tissue repair, and remodeling. In order to fulfill their different functional roles, macrophages can polarize into a series of phenotypes, including classic (pro inflammatory, M1) and alternative (anti-inflammatory, healing promoting, M2) activation states, as well as a wide range of regulatory phenotypes and subtypes. Macrophages exist in all vertebrate tissues and have a dual function in host protection and tissue damage, maintaining a good balance.

MCE designs a unique collection of 264 macrophage related compounds. It is a good tool to be used for research on Inflammation, cancer and other diseases.

With the progress of modern cancer therapy, the life of cancer patients has been extended. However, after initial treatment and recovery, the development of secondary tumors often leads to cancer recurrence. Cancer stem cells are a small number of cells that tumor growth and reproduction depend on.

Cancer stem cells have strong self-renewal ability, which is the direct cause of tumor occurrence. In addition, cancer stem cells also have the ability to differentiate into different cell types, playing a crucial role in tumor metastasis and development. Chemotherapy and radiotherapy induced DNA damage and apoptosis are common cancer treatments. However, cancer stem cells can effectively protect cancer cells from apoptosis by activating DNA repair ability. Cancer stem cells are regarded as the key "seed" of tumor occurrence, development, metastasis and recurrence. Since its first discovery in leukemia in 1994, cancer stem cells have been considered a promising therapeutic target for cancer treatment.

MCE supplies a unique collection of 3,355 compounds targeting key proteins in cancer stem cells. MCE Cancer Stem Cells Compound Library is a useful tool for cancer stem cells related research and anti-cancer drug development.

MCE Modified Van Gieson Staining Kit employs Celestine Blue and Mayer’s hematoxylin for nuclear staining, providing clearer and more stable nuclear visualization while facilitating longer preservation of stained sections. Ponceau S is used for collagen fiber staining, offering stable coloration and strong resistance to fading. This method enables effective differentiation between collagen fibers and muscle fibers, and can assist in distinguishing collagen fiber–derived tumors from myogenic tumors to a certain extent. It is also suitable for observing tissue or organ injury, repair processes, and the degree of fibrosis.