The COVID-19 pandemic and the potential treatment of the novel coronavirus SARS-CoV-2.

Coronavirus SARS-CoV-2 is a novel coronavirus and the seventh that can infect human beings and result in severe and acute respiratory syndrome and deaths. Currently, the world is undergoing a global health emergency due to the SARS-CoV-2 pandemic. As of May 18, SARS-CoV-2 has spread to over two hundred countries and infected more than 4.

The antimicrobial peptides and their potential clinical applications.

Nowadays, the bacterial drug resistance leads to serious healthy problem worldwide due to the long-term use and the abuse of traditional antibiotics result in drug resistance of bacteria. Finding a new antibiotic is becoming more and more difficult. Antimicrobial peptides (AMPs) are the host defense peptides with most of them being the cationic (positively charged) and amphiphilic (hydrophilic and hydrophobic) α-helical peptide molecules.

Notch Signaling Activation in Cervical Cancer Cells Induces Cell Growth Arrest with the Involvement of the Nuclear Receptor NR4A2.

Cervical cancer is a second leading cancer death in women world-wide, with most cases in less developed countries. Notch signaling is highly conserved with its involvement in many cancers. In the present study, we established stable cervical cell lines with Notch activation and inactivation and found that Notch activation played a suppressive role in cervical cancer cells.

Valproic acid induces NET cell growth arrest and enhances tumor suppression of the receptor-targeted peptide-drug conjugate via activating somatostatin receptor type II.

Background: Human pancreatic carcinoids, a type of neuroendocrine tumors, are asymptomatic and difficult to diagnose, with the effects of traditional anti-cancer therapies being limited. The histone deacetylase (HDAC) inhibitor valproic acid (VPA) was evaluated for its effects alone and in combination with receptor-targeting peptide-drug conjugate via increasing drug internalization.

Materials And Methods: The in vitro and in vivo assays were used to evaluate the effects of VPA and somatostatin receptor-targeting camptothecin-somatostatin conjugate (CPT-SST).

Lanreotide and its Potential Applications in Polycystic Kidney and Liver Diseases.

Multiple Gαi protein-coupled somatostatin receptors (SSTRs) are expressed in human kidney and liver tissues. Also, aberrant cAMP signaling has been shown to play a critical role in cysto-genesis and enlargement of the human kidney and liver. Thus, somatostatin (SST) analogs become potential and promising alternatives in treating human polycystic kidney disease (PKD) and polycystic liver disease (PLD) via interacting with Gαi protein-coupled SSTRs and further blocking cAMP production.

Valproic acid suppresses cervical cancer tumor progression possibly via activating Notch1 signaling and enhances receptor-targeted cancer chemotherapeutic via activating somatostatin receptor type II.

Purpose: We investigated the effects of the anti-epilepsy drug valproic acid (VPA) alone and in combination in treating cervical cancer.

Methods: VPA was investigated for its effects on cervical cancer Hela cell proliferation and tumor growth via in vitro and in vivo assays.

Results: VPA induce cell growth suppression and cell cycle arrest, with an increase of Notch1 that acts as a tumor suppressor and the change of other tumor-associated genes such as p21, p63 and PCNA.

Notch1-mediated tumor suppression in cervical cancer with the involvement of SST signaling and its application in enhanced SSTR-targeted therapeutics.

The role of Notch signaling in cervical cancer is seemingly controversial. To confirm the function of Notch signaling in this type of cancer, we established a stable Notch1-activated cervical cancer HeLa cell line. We found that Notch1 activation resulted in apoptosis, cell cycle arrest, and tumor suppression.

Investigation of cancer cell lines for peptide receptor-targeted drug development.

Many tumors highly express specific populations of G-protein-coupled receptors (GPCRs) that could be utilized for receptor-targeted therapy. We confirmed significant quantities of mRNAs specific for certain somatostatin (SST), vasoactive intestinal peptide (VIP), and bombesin (BN) receptors in various commercially available tumor cell lines. Very few of the tumor cell lines examined displayed the high receptor-binding affinity despite exhibiting the expression of appropriate mRNAs and proteins of the cognate receptors.

Application of human pancreatic carcinoid BON cells for receptor-targeted drug development.

In our previous study, we found that several tumor cell lines displayed high receptor-specific binding affinity, one of which, the human pancreatic carcinoid BON cell line, demonstrates high affinity binding of the bombesin (BN) and somatostatin (SST) receptor-specific ligands. In the present study, BON cells, as a representative model, were further applied to evaluate various peptide analogs and cytotoxic receptor-targeted peptide conjugates. We observed quick ligand-receptor internalization in BON cells as well as high binding affinity.

Targeted chemotherapy using a cytotoxic somatostatin conjugate to inhibit tumor growth and metastasis in nude mice.

The major problems of traditional chemotherapy are non-selectivity and non-specificity, resulting in severe toxic side effects. Peptides are a new-generation of drug-delivery vector to increase efficacy of this therapy and avoid the resulting damage. The cytotoxic somatostatin (SST) conjugate JF-10-81 was developed by coupling camptothecin (CPT) to the N-terminus of a SST analog (JF-07-69) using an activated carbamate linker.

Effects of camptothecin on tumor cell proliferation and angiogenesis when coupled to a bombesin analog used as a targeted delivery vector.

The camptothecin-bombesin conjugate termed DC-51-43, as a novel targeted drug delivery system, was examined in over 10 human tumor cell lines and shows a potent antiproliferative activity. This conjugate has also demonstrated its antitumor activity in our previous experiments. In our present study, we evaluate this conjugate for its antiangiogenic activity by in-vitro and in-vivo experiments.

In vitro and in vivo antitumor effects of cytotoxic camptothecin-bombesin conjugates are mediated by specific interaction with cellular bombesin receptors.

Most human tumors overexpress or ectopically express peptide hormone/neurotransmitter receptors, which are being increasingly studied as a means to selectively deliver cytotoxic agents. Although a number of peptide ligand-constructs demonstrate tumor cytotoxicity, the role of specific tumoral receptor interaction in its mediation is unclear. To address this question, we synthesized camptothecin (CPT) bombesin (Bn) analogs, in which CPT was coupled via a novel carbamate linker, L2 [N-(N-methyl-amino-ethyl)-glycine carbamate], that were chemically similar but differed markedly in their potency/affinity for human Bn receptors.

A conjugate of camptothecin and a somatostatin analog against prostate cancer cell invasion via a possible signaling pathway involving PI3K/Akt, alphaVbeta3/alphaVbeta5 and MMP-2/-9.

Camptothecin (CPT) was conjugated to the N-terminal of a somatostatin analog (SSA) directly via a carbamate group and a basic N-terminal linking motif, D-Lys-D-Tyr-Lys-D-Tyr-D-Lys. This new CPT-SSA conjugate termed JF-10-81 was evaluated as a receptor-specific delivery system for its anti-invasive and anti-angiogenic activities. It was found that, in addition to blocking migration and invasion of highly invasive prostate cancer PC-3 cells, this conjugate also inhibited in vitro capillary-like tube formation of endothelial cells and in vivo angiogenesis in C57B1/6N female mice.