Comparative Proteomic Analysis of Human Cholangiocarcinoma Cell Lines: S100A2 as a Potential Candidate Protein Inducer of Invasion

Inhibition of Tumor Growth against Chemoresistant Cholangiocarcinoma by a Proapoptotic Peptide Targeting Interleukin-4 Receptor

Cholangiocarcinoma (CCA) has a poor prognosis and high chemoresistance. Interleukin-4 receptor (IL-4R) is overexpressed in several cancer cells and plays a crucial role in tumor progression and drug resistance. IL4RPep-1, an IL-4R-binding peptide, has been identified by phage display and used for tumor targeting. In this study, we exploited IL4RPep-1 to guide the tumor-specific delivery of a proapoptotic peptide to chemoresistant CCA, thereby inhibiting tumor growth. Immunohistochemistry of human primary CCA tissues showed that IL-4R levels were upregulated in moderately to poorly differentiated types, and higher levels of IL-4R are correlated with lower survival rates in patients with CCA. IL4RPep-1 was observed to preferentially bind with high IL-4R-expressing KKU-213 human CCA cells, whereas it barely bound with low IL-4R-expressing KKU-055 cells. A hybrid of IL4RPep-1 and a proapoptotic peptide (KLAKLAK)2 (named as IL4RPep-1-KLA) induced cytotoxicity and apoptosis in KKU-213 cells and increased those levels induced by 5-fluorouracil (5-FU). IL4RPep-1-KLA was internalized in the cells and colocalized with mitochondria. Whole-body fluorescence imaging and immunohistochemical analysis of tumor tissues showed the homing of IL4RPep-1-KLA as well as IL4RPep-1 to KKU-213 tumor in mice. Systemic administration of IL4RPep-1-KLA efficiently inhibited KKU-213 tumor growth, whereas treatment with 5-FU alone did not significantly inhibit tumor growth in mice. No significant systemic side effects including liver toxicity and immunotoxicity were observed in mice during peptide treatments. These findings suggest that IL4RPep-1-KLA holds potential as a targeted therapeutic agent against chemoresistant CCA.

Proteomic studies of plant and bacteria interactions during benzene remediation

Phytoremediation is a sustainable remedial approach for removing benzene from environment. Plant associated bacteria could ameliorate the phytotoxic effects of benzene on plant, although the specificity of these interactions is unclear. Here, we used proteomics approach to gain a better understanding of the mechanisms involved in plant-bacteria interactions. Plant associated bacteria was isolated and subsequently inoculated into the sterilized Helianthus annuus, and the uptake rates of benzene by these inoculated plants were evaluated. At the end of the experiment, leaves and roots proteins were analyzed. The results showed inoculated H. annuus with strain EnL3 removed more benzene than other treatments after 96 h. EnL3 was identified as Enterobacter sp. according to 16S rDNA analysis. Based on the comparison of proteins, 62 proteins were significantly up or down regulated in inoculated leaves, while 35 proteins were significantly up or down regulated in inoculated roots. Furthermore, there were 4 and 3 identified proteins presented only in inoculated H. annuus leaves and roots, respectively. These proteins involved in several functions including transcription and translation, photosynthesis, and stress response. The network among anti-oxidant defense system, protein synthesis, and photosynthetic electron transfer are involved in collaboratively activate the benzene uptake and stress tolerance in plant.

Culture degeneration in conidia of Beauveria bassiana and virulence determinants by proteomics

The quality of Beauveria bassiana conidia directly affects the virulence against insects. In this study, continuous subculturing of B. bassiana on both rice grains and potato dextrose agar (PDA) resulted in 55 and 49 % conidial yield reduction after 12 passages and 68 and 60 % virulence reduction after 20 and 12 passages at four d post-inoculation, respectively. The passage through Tenebrio molitor and Spodoptera exigua restored the virulence of rice and PDA subcultures, respectively. To explore the molecular mechanisms underlying the conidial quality and the decline of virulence after multiple subculturing, we investigated the conidial proteomic changes. Successive subculturing markedly increased the protein levels in oxidative stress response, autophagy, amino acid homeostasis, and apoptosis, but decreased the protein levels in DNA repair, ribosome biogenesis, energy metabolism, and virulence. The nitro blue tetrazolium assay verified that the late subculture's colony and conidia had a higher oxidative stress level than the early subculture. A 2A-type protein phosphatase and a Pleckstrin homology domain protein Slm1, effector proteins of the target of rapamycin (TOR) complex 1 and 2, respectively, were dramatically increased in the late subculture. These results suggest that TOR signalling might be associated with ageing in B. bassiana late subculture, in turn affecting its physiological characteristics and virulence.