The effect of alkaloid from Oxytropis ochrocephala on growth inhibition and expression of PCNA and p53 in mice bearing H22 Hepatocellular Carcinoma

The genus Oxytropis DC: application, phytochemistry, pharmacology, and toxicity

OBJECTIVES

Oxytropis DC is a perennial plant of Fabaceae family, which is widely distributed in the northern temperate zone. It is known as "locoweed" because of its toxic component swainsonine. However, it is widely used in Tibetan medicine and Mongolian medicine, mainly for the treatment of heat-clearing and detoxifying, pain-relieving, anti-inflammatory, hemostasis, and other diseases. To provide a basis for the further development and utilization of Oxytropis DC, the pieces of literature about the application, phytochemistry, pharmacological action, and toxicity of Oxytropis DC were reviewed and analyzed.

KEY FINDINGS

A total of 373 chemical constituents were found from Oxytropis DC, including flavonoids, alkaloids, steroids, terpenoids, and others. Pharmacological actions mainly include antitumor, antioxidation, anti-inflammatory, analgesic, antibacterial, antifibrosis, and other pharmacological actions, among them, the antitumor effect is particularly prominent.

SUMMARY

At present, studies on its pharmacological effects are mainly concentrated on the extracts, some flavonoids, and alkaloids. In the follow-up studies, research on the pharmacological activities of the other chemical constituents in Oxytropis should be strengthened. It has the potential to pave the way for research and development of novel Oxytropis medicines.

Alkaloid and acetogenin-rich fraction from Annona crassiflora fruit peel inhibits proliferation and migration of human liver cancer HepG2 cells

Plant species from Annonaceae are commonly used in traditional medicine to treat various cancer types. This study aimed to investigate the antiproliferative potential of an alkaloid and acetogenin-rich fraction from the fruit peel of Annona crassiflora in HepG2 cells. A liquid-liquid fractionation was carried out on the ethanol extract of A. crassiflora fruit peel in order to obtain an alkaloid and acetogenin-rich fraction (AF-Ac). Cytotoxicity, proliferation and migration were evaluated in the HepG2 cells, as well as the proliferating cell nuclear antigen (PCNA), vinculin and epidermal growth factor receptor (EGFR) expression. In addition, intracellular Ca2+ was determined using Fluo4-AM and fluorescence microscopy. First, 9 aporphine alkaloids and 4 acetogenins that had not yet been identified in the fruit peel of A. crassiflora were found in AF-Ac. The treatment with 50 μg/mL AF-Ac reduced HepG2 cell viability, proliferation and migration (p < 0.001), which is in accordance with the reduced expression of PCNA and EGFR levels (p < 0.05). Furthermore, AF-Ac increased intracellular Ca2+ in the HepG2 cells, mobilizing intracellular calcium stores, which might be involved in the anti-migration and anti-proliferation capacities of AF-Ac. Our results support the growth-inhibitory potential of AF-Ac on HepG2 cells and suggest that this effect is triggered, at least in part, by PCNA and EGFR modulation and mobilization of intracellular Ca2+. This study showed biological activities not yet described for A. crassiflora fruit peel, which provide new possibilities for further in vivo studies to assess the antitumoral potential of A. crassiflora, especially its fruit peel.

Epigallocatechin gallate inhibits dimethylhydrazine-induced colorectal cancer in rats

BACKGROUND

Epigallocatechin gallate (EGCG) is a polyhydroxy phenolic compound extracted from tea and its antitumor effect has received widespread attention. We explored the inhibitory effect of EGCG on dimethylhydrazine (DMH)-induced colorectal cancer (CRC) using a rat model, predicted the interaction between EGCG and CRC target genes using a database, and explained the EGCG associated target pathways and mechanisms in CRC.

AIM

To understand the inhibitory mechanisms of EGCG on CRC cell proliferation and identify its pharmacological targets by network pharmacology analysis.

METHODS

DMH (40 mg/kg, s.c., twice weekly for eight weeks) was used to induce CRC in rats. After model establishment, the rats were administered with EGCG (50, 100, or 200 mg/kg, p.o., once daily for eight weeks) and killed 12 and 20 wk after the start of the experiment. Formation of aberrant crypt foci and tumor was studied by histological analysis. Using network pharmacology analysis, candidate and collective targets of EGCG and CRC were identified, and Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes analyses were used to predict the pathways altered by EGCG.

RESULTS

At week 12, high-dose EGCG treatment significantly reduced the tumor formation rate, total number of tumors, cancerous and non-cancerous tumors, tumor volume, ascites formation, and aberrant crypt foci count. At week 20, all three doses of EGCG were effective. Seventy-eight collective targets of EGCG and CRC were identified, of which 28 genes were dysregulated in CRC. Kyoto Encyclopedia of Genes and Genomes and GO analyses showed that the dysregulated genes were enriched in hsa05210 (CRC), hsa04115 (p53 signaling pathway), and hsa04151 (PI3K-Akt signaling pathway), GO:0043124 (negative regulation of I-kappaB kinase/NF-kappaB signaling pathway), GO:0043409 (negative regulation of mitogen-activated protein kinase cascade), and GO:2001244 (positive regulation of intrinsic apoptotic signaling pathway) respectively.

CONCLUSION

EGCG inhibits the formation of DMH-induced CRC by regulating key pathways involved in tumorigenesis.

URD12: A urea derivative with marked antitumor activities

Urea derivatives have been widely used in biology and medicine. The substituted urea derivative URD12 introduced in this study exhibits cytotoxic activity against the K562 human leukemia and KB human mouth epidermal carcinoma cell lines. To further study the bioactivity of URD12 and examine its feasibility as a new antitumor drug, we applied in vivo and in vitro assays to investigate the antitumor activity of URD12. URD12 was prepared and its cytotoxicity was evaluated using the BGC-823 human gastric carcinoma, MGC-803 human gastric carcinoma, SMMC-7721 human hepatoma and HepG2 human hepatocellular carcinoma cell lines using MTT assays. Antitumor activity in vivo was confirmed in mice bearing H22 hepatocellular carcinoma cells. Organ coefficient was used to further elucidate the cytotoxic mechanisms of URD12. URD12 inhibited the growth of tested tumor cell lines in vitro and the growth of H22 mouse hepatocellular carcinoma in vivo with no effects on the weight, spleen and thymus coefficient of tumor-bearing mice. In conclusion, our findings indicate that URD12 is an effective antitumor agent without evident immunosuppression effects.

Protective effects of fraction 1a of polysaccharides isolated from Solanum nigrum Linne on thymus in tumor-bearing mice

AIM OF THE STUDY

To further screen out the anti-tumor active compound of polysaccharides isolated from Solanum nigrum Linne (SNL-P), which had shown to have anti-cervical cancer and modulating properties, and evaluate the thymus protective effects of this active compound.

MATERIAL AND METHODS

SNL-P was separated and purified by column chromatography, and its anti-cervical cancer activity was evaluated by mice models injected of ascites U14 cells. Furthermore, the protective effect of fraction 1a of SNL-P (SNL-P1a) on the thymus tissue of tumor-bearing mice was evaluated by histological study and TUNEL staining. Finally, the protein expression of Bcl-2 and Bax gene were assayed by immunohistochemistry.

RESULTS

SNL-P1a has shown a marked inhibition effect on U14 cevical cancer, it restore the ratio of CD4(+)/CD8(+) peripheral blood T-lymphocyte subpopulation. Histological study and TUNEL staining results showed that SNL-P1a protect thymus tissue against the onslaught of tumor by inhibiting thymus lymphocyte apoptosis, and immunohistochemistry assay displayed that SNL-P1a treatment could increase Bcl-2/Bax ratio in thymus lymphocytes of tumor-bearer, which might promote more thymus lymphocytes towards proliferation.

CONCLUSION

SNL-P1a had significant growth inhibition effect on U14 cervical cancer and protective effect on thymus tissue of tumor-bearing mice.

Aqueous extract of Solanum nigrum inhibit growth of cervical carcinoma (U14) via modulating immune response of tumor bearing mice and inducing apoptosis of tumor cells

To explore the antitumor activity of aqueous extract of Solanum nigrum (SNL-AE) and its possible mechanism, we examined the effects of SNL-AE on the tumor growth in vivo, the number of CD4+, CD8+ T lymphocyte subsets of peripheral blood in tumor-bearing mice by means of FACScan flow cytometer, the expression of PCNA in U14 cervical carcinoma section by means of immunohistochemistry SP method, the cell cycle of transplanted tumor by means of FACScan flow cytometer and DNA fragmentation by means of agarose gel electrophoresis. Our results showed that SNL-AE could inhibit U14 cervical carcinoma growth and increased the number of CD4+ T lymphocyte subsets as well as the ratio of CD4+/CD8+ T lymphocyte, decreased the number of CD8+ T lymphocyte subsets of tumor-bearing mice and PCNA positive cells. Furthermore, it had the abilities to cause cell cycle arrest in G0/G1 phase and to induce apoptosis of more transplanted tumor cells in a dose-dependent manner. These results indicated that SNL-AE could suppress the cervical carcinoma via modulating immune response of the tumor-bearing mice and causing tumor cell cycle arrest in G0/G1 phase, as well as inducing apoptosis with little toxicity to the animals.

Antitumor activity of the procyanidins from Pinus koraiensis bark on mice bearing U14 cervical cancer

Pinus koraiensis Bark Procyanidins Extract (PKBPE) has been used in traditional Chinese medicine for thousands of years. In this study, we determined PKBPE effect on tumor weight, SOD (superoxidate dismutase) activity, the content of MDA (malondialdehyde) through colorimetric analysis antigenic, and expression of Ki-67, p53 and Bcl-2 on mice bearing U14 cervical cancer. Treatment with PKBPE (158 and 250 mg/kg body weight, p.o.) could inhibit U14 cervical carcinoma growth up to 47.68 and 58.94%. In addition, PKBPE enhance the activity of SOD (p<0.01) and decrease MDA content. Furthermore, we also observed that PKBPE treatment significantly inhibited the expression of Ki-67, mutant p53 and Bcl-2 protein (p<0.01). The results suggested that PKBPE showed antitumor activities on U14 cervical carcinoma mice. The mechanism of PKBPE antitumor activity might be associated with free radical production inhibition and regulation of the expression of Ki-67, mutant p53 and Bcl-2 protein.

Antitumor activity of crude polysaccharides isolated fromSolanum nigrum Linne on U14 cervical carcinoma bearing mice

Solanum nigrum Linne (SNL) has been used in traditional Chinese medicine for centuries because of its diuretic and antipyretic effects. The present study examined the effect of the crude polysaccharides isolated from Solanum nigrum Linne (SNL-P) on tumor growth. SNL-P had a significant growth inhibition effect on cervical cancer (U14) of tumor-bearing mice. Further analysis of the tumor inhibition mechanism indicated that the number of apoptotic tumor cells increased significantly, the expression of Bax increased and the expression of Bcl-2 and mutant p53 decreased dramatically in cervical cancer sections after oral administration of SNL-P for 12 days. Moreover, SNL-P treatment decreased the level of blood serum TNF-alpha. These results indicated that the tumor growth inhibition of SNL-P administration might correlate with the reduction of TNF-alpha level of blood serum, which resulted in a massive necrosis in tumor tissues and the up-regulation of Bax and down-regulation of Bcl-2 and mutant p53 gene expression, which triggered apoptosis in tumor cells. These findings demonstrated that the SNL-P is a potential antitumor agent.