MiR-122-5p regulates the mevalonate pathway by targeting p53 in non-small cell lung cancer

The 5-year survival rate of non-small cell lung cancer (NSCLC) patients is very low. MicroRNAs (miRNAs) are involved in the occurrence of NSCLC. miR-122-5p interacts with wild-type p53 (wtp53), and wtp53 affects tumor growth by inhibiting the mevalonate (MVA) pathway. Therefore, this study aimed to evaluate the role of these factors in NSCLC. The role of miR-122-5p and p53 was established in samples from NSCLC patients, and human NSCLC cells A549 using the miR-122-5p inhibitor, miR-122-5p mimic, and si-p53. Our results showed that inhibiting miR-122-5p expression led to the activation of p53. This inhibited the progression of the MVA pathway in the NSCLC cells A549, hindered cell proliferation and migration, and promoted apoptosis. miR-122-5p was negatively correlated with p53 expression in p53 wild-type NSCLC patients. The expression of key genes in the MVA pathway in tumors of p53 wild-type NSCLC patients was not always higher than the corresponding normal tissues. The malignancy of NSCLC was positively correlated with the high expression of the key genes in the MVA pathway. Therefore, miR-122-5p regulated NSCLC by targeting p53, providing potential molecular targets for developing targeted drugs.

[Active ingredients and in vitro anti-inflammatory effects of Polygoni Cuspidati Rhizoma et Radix decoction pieces by integrated processing and traditional processing: a comparative analysis]

The present study explored the differences in active ingredients and in vitro anti-inflammatory effects of the decoction pieces by integrated processing(IPDP) and traditional processing(TPDP) of Polygoni Cuspidati Rhizoma et Radix(PCRER).The content of polydatin, resveratrol, emodin-8-O-β-D-glucoside, emodin, and physcion in IPDP and TPDP was determined by high-performance liquid chromatography(HPLC).The inflammation model was induced by lipopolysaccharide(LPS) in RAW264.7 cells.The mRNA levels of inflammatory cytokines tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), and interleukin-1β(IL-1β) in 60% ethanol extracts of IPDP and TPDP of different concentrations(5 and 10 μg·mL~(-1)) were determined by PCR.The results showed that the content of polydatin and emodin-8-O-β-D-glucoside in IPDP was significantly higher than that in TPDP, while the content of resveratrol, emodin, and physcion was higher in TPDP.The anti-inflammatory results showed that ethanol extracts of IPDP of different concentrations(5 and 10 μg·mL~(-1)) significantly inhibited the increase in the mRNA levels of IL-1β and TNF-α induced by LPS, whereas TPDP only had a significant inhibitory effect on IL-1β.This study preliminarily showed that the total content of five active ingredients in IPDP was higher than that in TPDP, and IPDP was superior to TPDP in anti-inflammatory activity in vitro, which provided an experimental basis for the production and application of IPDP.

The first vitellogenin receptor from a Lepidopteran insect: molecular characterization, expression patterns and RNA interference analysis

The vitellogenin receptor (VgR) belongs to the low-density lipoprotein receptor (LDLR) superfamily, and is an important carrier for the uptake of vitellogenin (Vg) into developing oocytes of all oviparous species. The first full-length message for a VgR from a Lepidopteran insect was cloned and sequenced from the ovary of Spodoptera litura Fabricius (GenBank accession no. GU983858). The coding region consisted of 5370 bp flanked by a 49 bp 5'-untranslated region (UTR) and a 177 bp 3'-UTR, which encoded a 1798-residue protein with a predicted molecular weight (MW) of 201.69 kDa. S. litura VgR (SlVgR)comprised two ligand binding sites with four LDLR class A repeats in the first domain and seven in the second domain, an epidermal growth factor-like domain containing an LDLR class B repeat and a YWXD motif, a transmembrane domain and a cytoplasmic domain. A phylogenetic relationship placed SlVgR as a separate group from the other insects. SlVgR messenger RNA (mRNA) was specifically expressed in the ovarian tissues. The developmental expression patterns showed that VgR mRNA was first transcribed in 6(th) day female pupae and the maximum level of VgR mRNA appeared in 36-h-old adults. Immunoblot analysis detected an ovary-specific VgR protein with a MW of ∼200 kDa, whose development profiles were consistent with VgR mRNA expression patterns. RNA inteference (RNAi) specifically disrupted the VgR gene by injection of 3 or 5 µg VgR double-stranded RNA per insect in 4(th) or 6(th) day pupae. RNAi of SlVgR led to a phenotype characterized by high Vg accumulation in the haemolymph, low Vg deposition in the ovary and the failure of insect spawning. These results mean that VgR is critical for binding Vg and transporting it into the oocytes of the insect ovary, thus playing an important role in insect reproduction.

Specific targeting of mitomycin C to tumors by anti-gastric cancer monoclonal antibody

In the present study, an anti-gastric cancer monoclonal antibody, MGb2, was chosen to prepare antibody-mitomycin C (MMC) conjugate with dextran T-40 as intermediary. Twenty molecules of MMC were introduced into each molecule of antibody while the antigen-binding capacity of the antibody was kept well. The conjugate showed selective cytotoxicity upon human gastric cancer cell line SGC-7901. Radioimmunoimaging and biodistribution studies indicated that after conjugation with MMC via dextran T-40 as intermediary, the tumor localization capacity of the antibody was well retained. When tested in nude mice, inoculated with human gastric carcinoma SGC-7901 in bilateral subrenal capsules, intraperitoneal injection of the conjugate daily for 6 days at a dose of 1 mg/kg gave a tumor inhibitory rate of 68.67%, which was far better than that of free MMC or irrelevant conjugate. No synergetic effect was found in regard to the mixture of MGb2 with MMC.

Preparation of antigastric cancer monoclonal antibody MGb2-mitomycin C conjugate with improved antitumor activity

In the present study, an antigastric cancer monoclonal antibody, MGb2, was chosen to prepare antibody-mitomycin C conjugate with dextran T-40 as intermediary. Up to 20 molecules of mitomycin C were specifically bound per molecule of antibody, without significantly impairing the antigen-binding capacity of the antibody and the pharmacological activity of mitomycin C. The conjugate showed selective cytotoxicity upon human gastric cancer cell line SGC-7901 in vitro. Radioimmunoimaging and biodistribution studies indicated that, after conjugation with mitomycin C via dextran T-40 as intermediary, the tumor localization capacity of the antibody was well-retained. When tested in nude mice inoculated with human gastric carcinoma GAII in bilateral subrenal capsules, intraperitoneal injection of the conjugate twice a week for 3 weeks at the dose of 1 mg/kg of drug gave a tumor inhibitory rate of 152.29%, the result being far better than that of free mitomycin C or an irrelevant conjugate. A similar result was found in another nude mouse model of human gastric carcinoma SGC-7901. Meanwhile, after conjugation with antibody, the toxicity of mitomycin C on tested animals was significantly reduced.

[Therapeutic effects of 9 antitumor drugs on stomach adenocarcinoma (MKN-28) in nude mice]

Therapeutic effects of 9 antitumor drugs were studied on nude mice inoculated with transplanted human stomach tumor (MKN-28). When cisplatin, cyclophosphamide, chlormethine, 5-fluorouracil or mitomycin C was given ip to nude mice bearing MKN-28 at respective dose of 3, 100, 40, 80 and 2 mg/kg once weekly for 3 wk, the tumor inhibition rates of the former 3 drugs were over 80%, while the later 2 were 70-77%. Cytarabine 200 mg/kg twice or thrice weekly for 3 wk gave an inhibition rate of 68-72%. Hydroxycamptothecin 20 mg/kg twice weekly for 3 wk showed a better therapeutic effect than that given at 40 mg/kg once weekly for 3 wk, the tumor inhibition rates were 65 and 32% respectively. No apparent effect of vincristine and methotrexate on MKN-28 was seen. Histopathological observation indicated that in cisplatin group, numerous necrotic areas of tumor cells as well as sparse infiltration of inflammatory cells were found.

[Effects of 8 antitumor drugs against the growth of human lung adenocarcinoma (LAX-83) transplanted under the kidney capsule of nude mice]

Nude mice, inoculated with LAX 83 in bilateral subrenal capsules, were used in experimental therapy with 8 antitumor drugs. Treatment was initiated 2 d after tumor inoculation. All the drugs were ip to the nude mice daily for 7 d. At the daily doses VCR 0.4, MMC 2, CCNU 16, cis-DDP 2, AdM 2.5, 5-Fu 30, CTX 40 and MTX 2-6 mg/kg, the inhibition of the tumor growth were 100, 95.8, 91.3, 79.2, 65.2, 60.7, 62.3 and 0%, respectively. The results indicated that the effects of the drugs on nude mice inoculated with LAX-83 in subrenal capsule not only exhibited a good correlation to those in sc, but also shortened the period of experiment from 22 to 11 d. Furthermore, when LAX-83 was inoculated into the subrenal capsule of Swiss +/+ mice, the tumor tissues degenerated and disintegrated 2 d after the inoculation and replaced by inflammatory granuloma tissues 6 d later.

[Transplantation model of human lung oat cell carcinoma in nude mice]

A human lung oat cell carcinoma from a surgical specimen was successfully transplanted into nude mice and has been maintained for over four years through 14 passages. This transplanted tumor had a long latent period of more than one month, slowly growing in the initial inoculation and the following passages. The interval between two passages was about four months. 5 months after the inoculation, the transplanted tumor in nude mice grew to 2 cm in diameter. It was demonstrated that the transplanted tumor possessed the human isoenzyme pattern and human chromosome karyotype. The original human tumor and its transplanted counterparts in the nude mice were strikingly similar by histopathology. Besides, specific neuro-secretory granules in cytoplasm of the transplanted tumor were observed under transmission electron microscope.