NF-ĸΒ1 knockout reduces IL6 expression under hypoxia in renal cell carcinoma

Renal cell carcinoma (RCC) is the most common adult renal epithelial cancer, accounting for more than 90% of all renal neoplasms. Clear cell RCC (ccRCC) is the most common subtype of RCC. Most patients with ccRCC have a mutation in the von Hippel-Lindau (VHL) tumor suppressor gene, which encodes a protein that downregulates various intracellular proteins, including hypoxia-inducible factor (HIF). Many molecules have been identified to be responsible for the aggressive phenotype of ccRCC, including the transcription factor nuclear factor kappa B (NF-кB). The increase in NF-кB activity observed in RCC is correlated with an increase in angiogenesis markers, such as interleukin 6 (IL-6). In recent years, several groups have demonstrated the functional role of NF-кB1 in RCC tumorigenicity. Herein, we used the CRISPR/Cas-9 technique to obtain an NF-кB1 knockout-human renal adenocarcinoma cell line. Expression of IL-6 at the mRNA and protein levels was analyzed under normoxia and hypoxia by real time-polymerase chain reaction and multiplex assay, respectively. The CRISPR/Cas9 technique was effective in producing 786-0 knockout cells for NF-κB1 (p105/p50), as confirmed by western blot analysis. Suppression of p50 expression in 786-0 single guide RNA (sg)1, 786-0 sg2 and 786-0 sg3 cells downregulated IL-6 mRNA and protein expression under normoxia and hypoxia. The observed decrease in the differential expression of IL-6 in hypoxia/normoxia is suggestive of a change in cellular responsiveness to hypoxia with respect to IL-6.

Zinc and Manganese Imbalances in BALB/c Mice Experimentally Infected with Leishmania (Leishmania) amazonensis

PURPOSE

The clinical progression of Leishmania (Leishmania) amazonensis infection depends on multiple factors, including immunological status of the host and their genotypic interaction. Several immunological processes depend directly on minerals for an efficient performance. Therefore, this study used an experimental model to investigate the alterations of trace metals in L. amazonensis infection associate with clinical outcome, parasite load, and histopathological lesions, and the effect of CD4 + T cells depletion on these parameters.

METHODS

A total of 28 BALB/c mice were divided into 4 groups: 1-non-infected; 2-treated with anti-CD4 antibody; 3-infected with L. amazonensis; and 4-treated with anti-CD4 antibody and infected with L. amazonensis. After 24 weeks post-infection, levels of calcium (Ca), iron (Fe), magnesium (Mg), manganese (Mn), Cu, and Zn were determined by inductively coupled plasma optical emission spectroscopy using tissue samples of the spleen, liver, and kidneys. Additionally, parasite burdens were determined in the infected footpad (inoculation site) and samples of inguinal lymph node, spleen, liver, and kidneys were submitted to histopathological analysis.

RESULTS

Despite no significant difference was observed between groups 3 and 4, L. amazonensis-infected mice had a significant reduction of Zn (65.68-68.32%) and Mn (65.98 to 82.17%) levels. Presence of L. amazonensis amastigotes was also detected in the inguinal lymph node, spleen, and liver samples in all infected animals.

CONCLUSION

The results showed that significant alterations in micro-elements levels occur in BALB/c mice experimentally infected with L. amazonensis and may increase the susceptibility of individuals to the infection.

Lanthanide-based β-Tricalcium Phosphate Upconversion Nanoparticles as an Effective Theranostic Nonviral Vectors for Image-Guided Gene Therapy

Lanthanide-based beta-tricalcium phosphate (β-TCP) upconversion nanoparticles are exploited as a non-viral vector for imaging guided-gene therapy by virtue of their unique optical properties and multi-modality imaging ability, high transfection efficiency, high biocompatibility, dispersibility, simplicity of synthesis and surface modification. Ytterbium and thulium-doped β-TCP nanoparticles (βTCPYbTm) are synthesized via co-precipitation method, coated with polyethylenimine (PEI) and functionalized with a nuclear-targeting peptide (TAT). Further, in vitro studies revealed that the nanotheranostic carriers are able to transfect cells with the plasmid eGFP at a high efficiency, with approximately 60% of total cells producing the fluorescent green protein. The optimized protocol developed comprises the most efficient βTCPYbTm/PEI configuration, the amount and the order of assembly of βTCPYbTm:PEI, TAT, plasmid DNA and the culturing conditions. With having excellent dispersibility and high chemical affinity toward nucleic acid, calcium ions released from βTCPYbTm:PEI nanoparticles can participate in delivering nucleic acids and other therapeutic molecules, overcoming the nuclear barriers and improving the transfection efficacy. Equally important, the feasibility of the upconversion multifunctional nanovector to serve as an effective contrast agent for imaging modality, capable of converting low-energy light to higher-energy photons via a multi-photons mechanism, endowing greater unique luminescent properties, was successfully demonstrated.

Radioimmunotheranostic Pair Based on the Anti-HER2 Monoclonal Antibody: Influence of Chelating Agents and Radionuclides on Biological Properties

The oncogene HER2 is an important molecular target in oncology because it is associated with aggressive disease and the worst prognosis. The development of non-invasive imaging techniques and target therapies using monoclonal antibodies is a rapidly developing field. Thus, this work proposes the study of the radioimmunotheranostic pair, [111In]In-DTPA-trastuzumab and [177Lu]Lu-DOTA-trastuzumab, evaluating the influence of the chelating agents and radionuclides on the biological properties of the radioimmunoconjugates (RICs). The trastuzumab was immunoconjugated with the chelators DTPA and DOTA and radiolabeled with [111In]InCl3 and [177Lu]LuCl3, respectively. The stability of the RICs was evaluated in serum, and the immunoreactive and internalization fractions were determined in SK-BR-3 breast cancer cells. The in vivo pharmacokinetics and dosimetry quantification and the ex vivo biodistribution were performed in normal and SK-BR-3 tumor-bearing mice. The data showed that there was no influence of the chelating agents and radionuclides on the immunoreactive and internalization fractions of RICs. In contrast, they influenced the stability of RICs in serum, as well as the pharmacokinetics, dosimetry and biodistribution profiles. Therefore, the results showed that the nature of the chelating agent and radionuclide could influence the biological properties of the radioimmunotheranostic pair.

Porphyrins are increased in the faeces of patients with prostate cancer: a case-control study

Background

Experimental models of prostate cancer have demonstrated increased levels of protoporphyrin IX (PpIX) in the blood and faeces of mice. Hence, the quantification of these autofluorescent molecules could be hypothesized to be a potential marker for this type of tumour. In this case-control study, the autofluorescence of porphyrins in human faeces from patients with prostate cancer and control subjects was analysed using fluorescence spectroscopy.

Methods

First, 3 mL of analytical-grade acetone was added to 0.3 g of faeces, and the mixture was macerated and centrifuged at 4000 rpm for 15 min. The supernatant was analysed spectroscopically. The emission spectra from 550 to 750 nm were obtained by exciting the samples at 405 nm.

Results

A significant difference between the samples from control and cancer subjects was established in the spectral region of 670–675 nm (p = 0.000127), which corresponds to a significant increase in faecal porphyrins in patients with cancer. There was no statistically significant correlation between PSA levels and faecal porphyrins.

Conclusion

In this preliminary study conducted in humans, the results show a simple and non-invasive method to assess faecal porphyrins, which have the potential to function as a tumour biomarker in patients with prostate cancer. This approach has improved sensitivity and specificity over PSA testing. Additional prospective studies with larger sample sizes are required to validate these findings.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-5030-1) contains supplementary material, which is available to authorized users.

Essential Elements as Biomarkers of Acute Kidney Injury and Spontaneous Reversion

Acute kidney injury (AKI) is an important health problem and can be caused by number of factors. The use of aminoglycosides, such as gentamicin, is one of these factors. Recently, an effort has been made to find biomarkers to guide treatment protocols. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to estimate the contents of Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn in serum and urine of the healthy, AKI, and spontaneous recovery (SR) groups of animals. The animal model of AKI and SR was validated by measuring serum and urinary urea and creatinine. The quantitative determination of the elements showed a decrease in serum levels of Ca, and Fe in the AKI group (P<0.01 vs. healthy), with a return to normal levels in the SR group, without a significant difference between the healthy and SR groups. In the urine samples, there was a decrease in P and Na levels in the AKI group (P<0.001 and P<0.01 vs. healthy), but Ca levels were increased in this group compared with the healthy and SR groups (P<0.01). These findings indicate that mineral elements might be useful as biomarkers for AKI.

Impact of endostatin gene therapy on myeloid-derived suppressor cells from a metastatic renal cell carcinoma

AIM

To evaluate the role of endostatin (ES) gene therapy on myeloid-derived suppressor cells (MDSC) in a metastatic model of renal cell carcinoma (RCC).

MATERIALS AND METHODS

Balb/C mice bearing orthotopic Renca tumors were treated with NIH/3T3-LendSN or, as a control, with NIH/3T3-LXSN cells. At the end of in vivo experiment, plasma and tissue lung samples were collected. Plasma ES and granulocyte colony stimulating factor (G-CSF) levels were measured by ELISA and Milliplex, respectively. Quantification of CD11b⁺Gr-1⁺ cells and their subsets was performed by flow cytometry. Reactive oxygen species (ROS) production was measured in CD11b⁺Gr-1⁺ MDSC using the DCFDA marker by flow cytometry.

RESULTS

Metastatic RCC (mRCC) induced expansions of CD11b⁺Gr-1⁺ MDSC and promoted accumulation of these cells and their subtypes in lymphoid organ and metastases. ES treatment promoted low G-CSF plasmatic levels which were produced by the tumor microenvironment, reflecting the reduced metastatic accumulation of CD11b⁺Gr-1⁺ MDSC in the lungs. However, the therapy was selective for granulocytic cells, thus reducing the production of ROS.

CONCLUSION

These findings confirm the expansion of MDSC during metastatic progression of RCC and indicate the important role of ES in reducing MDSC and possible use of ES therapy in combined anticancer treatment.

Knockdown of NF-κB1 by shRNA Inhibits the Growth of Renal Cell Carcinoma In Vitro and In Vivo

Renal cell carcinoma (RCC) accounts for approximately 2%–3% of human malignancies and is the most aggressive among urologic tumors. Biological heterogeneity, drug resistance, and chemotherapy side effects are the biggest obstacles to the effective treatment of RCC. The NF-κB transcription factor is one of several molecules identified to be responsible for the aggressive phenotype of this tumor. In the past decade, several studies have demonstrated the activation of NF-κB in RCC, and many have implicated NF-κB1 (p50) as an important molecule in tumor progression and metastasis. In the present study, a lentivirus was used to deliver shRNA targeting NF-κB1 into mouse RCC (Renca) cells. It was determined that the knockdown of the NF-κB1 gene led to a reduction in cell proliferation and late apoptosis/necrosis in vitro. Flow cytometry analysis demonstrated G₂/M arrest in the cells. In addition, immunoblotting analysis revealed a significant increase in cyclin B1 and Bax. In vivo experiments showed that Renca-shRNA-NF-κB1 cells have significantly diminished tumorigenicity. Moreover, immunohistochemical analysis revealed an increase in necrotic areas of Renca-shRNA-NF-κB1 tumors. Thus, this study indicates that downregulation of NF-κB1 can suppress RCC tumorigenesis by inducing late apoptosis/necrosis. Therefore, NF-κB1 may be a potential therapeutic target for RCC.

Involvement of the NF-кB/p50/Bcl-3 complex in response to antiangiogenic therapy in a mouse model of metastatic renal cell carcinoma

Renal cell carcinoma (RCC) represents approximately 2-3% of human malignancies. Nuclear transcription factor кB (NF-кB) is composed of a family of transcription factors that have been associated with the development and progression of RCC. Endostatin (ES) is a fragment of collagen XVIII that possesses antiangiogenic activity. In this study, we evaluated the expression of NF-кB in metastatic tumor cells from animals treated with ES. Balb/c-bearing Renca-EGFP cells were treated with NIH/3T3-LendSN or NIH/3T3-LXSN cells as a control. At the end of the in vivo experiment, plasma Renca-EGFP-sorted cells and tissue lung samples were collected. A real-time PCR array for NF-κB target genes revealed that ES therapy led to down regulation of Bcl-3 (P<0.031), NF-кB1 (P<0.001) and c-Rel (P<0.004) in the ES-treated group. Using an electrophoretic mobility shift assay (EMSA), we observed a reduction in NF-kB binding activity in ES-treated Renca-EGP cells. Furthermore, a supershift assay showed a clear shift of the NF-кB DNA band in samples incubated with a p50 antibody. By immunohistochemistry analysis, ES treatment resulted in a significant reduction in expression of p50. (ES vs. control P<0.05). The immunoprecipitation experiments confirmed the presence of a p50/Bcl-3 complex in nuclear extracts from cells of metastatic lung tissues. Our findings indicate that p50 and Bcl-3 plays a regulatory role in gene transcription in RCC.

Vascular endothelial growth factor as a biomarker for endostatin gene therapy

Renal cell carcinoma (RCC) is characterized by high vascular endothelial growth factor (VEGF) production and, consequently, excessive angiogenesis. Several strategies have been developed to target angiogenesis as a method for treating metastatic RCC (mRCC). Endostatin (ES) is a C-terminal fragment of collagen XVIII that has antiangiogenic activity. The aim of this study was to investigate the predictive value of circulating VEGF-A in a murine model of mRCC after ES gene therapy. ES therapy did not affect the levels of collagen XVIII/ES or ES in the tissue. The circulating level of ES was increased in the control and ES-treated groups (normal vs. control, P<0.05 and ES-treated vs. control, P<0.001), and the intratumoral vessels were significantly decreased (ES-treated vs. control, P<0.05). ES therapy decreased the VEGF mRNA levels. The tissue and circulating levels of VEGF in the control group were significantly higher than normal (P<0.01 and P<0.05, respectively). Treatment with ES significantly reduced the VEGF concentrations in both compartments (P<0.001 for tissue and P<0.05 for plasma). Our findings indicate that in addition to the directly targeted tumor vessels, ES exerts its antitumor effect by down-regulating VEGF gene expression in renal tumor cells. Additionally, our findings point to the predictive value of VEGF for ES therapy.

Endostatin gene therapy stimulates upregulation of ICAM-1 and VCAM-1 in a metastatic renal cell carcinoma model

One of the greatest challenges in urological oncology is renal cell carcinoma (RCC), which is the third leading cause of death in genitourinary cancers. RCCs are highly vascularized and respond positively to antiangiogenic therapy. Endostatin (ES) is a fragment of collagen XVIII that possesses antiangiogenic activity. In this study, we examined the potential of ES-based antiangiogenic therapy to activate tumor-associated endothelial cells in metastatic RCC (mRCC). Balb/c-bearing Renca cells were treated with NIH/3T3-LendSN or, as a control, with NIH/3T3-LXSN cells. The T-cell subsets and lymphocyte populations of tumors, mediastinal lymph nodes and the spleen were assessed by flow cytometry. The expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was assessed by real-time PCR, flow cytometry and immunohistochemistry analysis. ES gene therapy led to an increase in the percentage of infiltrating CD4-interferon (IFN)-γ cells (P<0.05), CD8-IFN-γ cells (P<0.01) and CD49b-tumor necrosis factor-α cells (P<0.01). In addition, ES therapy caused an increase at the mRNA level of ICAM-1 (1.4-fold; P<0.01) and VCAM-1 (1.5-fold) (control vs treated group; P<0.001). Through flow cytometry, we found a significant increase in the CD34/ICAM-1 cells (8.1-fold; P<0.001) and CD34/VCAM-1 cells (1.6-fold; P<0.05). ES gene therapy induced a significant increase in both T CD4 and CD8 cells in the lymph nodes and the spleen, suggesting that ES therapy may facilitate cell survival or clonal expansion. CD49b cells were also present in increased quantities in all of these organs. In this study, we demonstrate an antitumor inflammatory effect of ES in an mRCC model, and this effect is mediated by an increase in ICAM-1 and VCAM-1 expression in tumor-associated endothelial cells.

Pro-apoptotic effects of Amblyomin-X in murine renal cell carcinoma "in vitro"

Renal cell carcinoma (RCC) is one of the most lethal urologic cancers and is highly resistant to both radiotherapy and chemotherapy. The recombinant protein Amblyomin-X, characterized as a Kunitz-type protease inhibitor, was obtained from a cDNA library from the salivary glands of the Amblyomma cajennense tick. This paper reports the biological effect of Amblyomin-X on inducing cell death by apoptotic process in vitro. For this purpose, the changes in morphological aspects of cells, the phosphatidylserine exposition and DNA degradation were evaluated after treatment with Amblyomin-X. We found that Amblyomin-X was able to induce apoptosis in Renca cells in a dose-dependent manner. So, the results presented here open perspectives for new researches and developing for Amblyomin-X in the treatment of RCC.

Endostatin gene therapy enhances the efficacy of IL-2 in suppressing metastatic renal cell carcinoma in mice

We investigated whether the administration of IL-2 combined with endostatin gene therapy was able to produce additive or even synergistic immunomodulatory activity in a mouse model of metastatic renal carcinoma. Renca cells were injected into the tail vein of BALB/c mice. After 24 h, the animals were randomly divided into four groups (5 mice/group). One group of mice was the control, the second group received treatment with 100,000 UI of Recombinant IL-2 (Proleukin, Chiron) twice a day, 1 day per week during 2 weeks (IL-2), the third group received treatment with a subcutaneous inoculation of 3.6 x 10(6) endostatin-producing cells, and the fourth group received both therapies (IL-2 + ES). Mice were treated for 2 weeks. In the survival studies, 10 mice/group daily, mice were monitored daily until they died. The presence of metastases led to a twofold increase in endostatin levels. Subcutaneous inoculation of NIH/3T3-LendSN cells resulted in a 2.75 and 2.78-fold increase in endostatin levels in the ES and IL-2 + ES group, respectively. At the end of the study, there was a significant decrease in lung wet weight, lung nodules area, and microvascular area (MVA) in all treated groups compared with the control group (P < 0.001). The significant difference in lung wet weight and lung nodules area between groups IL-2 and IL-2 + ES revealed a synergistic antitumor effect of the combined treatment (P < 0.05). The IL-2 + ES therapy Kaplan-Meier survival curves showed that the probability of survival was significantly higher for mice treated with the combined therapy (log-rank test, P = 0.0028). Conjugated therapy caused an increase in the infiltration of CD4, CD8 and CD49b lymphocytes. An increase in the amount of CD8 cells (P < 0.01) was observed when animals received both ES and IL-2, suggesting an additive effect of ES over IL-2 treatment. A synergistic effect of ES on the infiltration of CD4 (P < 0.001) and CD49b cells (P < 0.01) was also observed over the effect of IL-2. Here, we show that ES led to an increase in CD4 T helper cells as well as cytotoxic lymphocytes, such as NK cells and CD8 cells, within tumors of IL-2 treated mice. This means that ES plays a role in supporting the actions of T cells.

Erythrocyte protoporphyrin fluorescence as a potential marker of diabetes

Protoporphyrin (PpIX), a porphyrin derivative, is the intermediate metabolic precursor of the heme molecule. Abnormal metabolism of total erythrocyte PpIX has been observed in diseases such as cancer, lead poisoning, psoriasis, iron deficiency anemia and acute porphyries. Diabetes mellitus (DM) is a complex metabolic syndrome in which hyperglycemia is the primary clinical manifestation and contributes to the diabetic complications. The aim of this study was to evaluate the utility of fluorescence spectroscopy of erythrocyte PpIX for monitoring the early stages of diabetes. A total of 14 male C 57BL mice, 6 weeks old, were divided into two groups: diabetic and non-diabetic. Diabetes was induced by intraperitoneal injection of streptozotocin (SZT). Blood cells were cultured with standard and 50 mM supplemented RPMI medium. Blood smears were prepared and stained for qualitative morphology analysis under optical microscopy. Blood porphyrin autofluorescence was analyzed by fluorescence spectroscopy. Characteristic PpIX emission spectra were obtained by exciting the samples at 405 nm. Average blood glucose was lower in the control group than in the diabetic group (156.50 +/- 8.11 mg/dL vs. 371.10 +/- 14.43 mg/dL, P < 0.05). Both diabetic and glucose-cultured erythroblasts showed a significant decrease (around 30.5% and 40%, respectively) in the emission band intensity at 635 nm. Our results indicate that the erythrocyte PpIX profile could be used as a biological monitor for diabetes.

Immobilized kidney 28-kDa endostatin-related (KES28kDa) fragment promotes endothelial cell survival

BACKGROUND/OBJECTIVE

Renal ischemia-hypoxia is a leading cause of acute kidney injury (AKI). Ischemia causes extracellular matrix breakdown of the tubular basement membrane. Endostatin (ES) is the C-terminal fragment of collagen XVIII generated by proteolytic cleavage. Recent studies have demonstrated that ES expression is upregulated in ischemic kidneys. The present study aimed to characterize ES from ischemic kidneys.

METHODS

Ischemic renal failure was induced via 45 min of occlusion of the left renal artery and vein. After the ischemic period, blood was collected. Kidneys were harvested and used for immunohistochemical testing and protein extraction. Three-step purification was used. Soluble and immobilized purified ES were tested in cell viability and adhesion assays. results: The soluble KES28kDa inhibited endothelial cell proliferation: 25 versus 12.5 microg (p < 0.05); 12.5 versus 3.15 microg (p < 0.05). Immobilization of KES28kDa supports endothelial cell survival over the control (p = 0.021). Human umbilical vein endothelial cells plated on immobilized KES28kDa showed an increase in membrane ruffles and stress fibers.

CONCLUSION

These data demonstrate the local synthesis of a 28-kDa ES-related fragment following AKI and suggest its role in endothelium survival.

Variation in the distribution of trace elements in renal cell carcinoma

The development of cancer is a complex, multistage process during which a normal cell undergoes genetic changes that result in phenotypic alterations and in the acquisition of the ability to invade other sites. Inductively coupled plasma optical emission spectroscopy was used to estimate the contents of Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, P, Pb, and Zn in healthy kidney and renal cell carcinoma (RCC), and significant differences were found for all elements. Along with the progression of the malignant disease, a progressive decrease of Cd and K was observed. In fact, for Cd, the concentration in stage T4 was 263.9 times lower than in stage T1, and for K, the concentration in stage T4 was 1.73 times lower than in stage T1. Progressive accumulation was detected for P, Pb, and Zn in stage T4. For P, the concentration in stage T4 was 11.1 times higher than in stage T1; for Pb, the concentration in stage T4 was 232.7 times higher than in T1; and for Zn, the concentration in T4 was 8.452 times higher than in T1. This study highlights the marked differences in the concentrations of selected trace metals in different malignant tumor stages. These findings indicate that some trace metals may play important roles in the pathogenesis of RCC.

Anti‐tumor effect of endostatin mediated by retroviral gene transfer in mice bearing renal cell carcinoma

We investigated whether transfer of the gene encoding the angiogenesis inhibitor endostatin into the NIH/3T3 fibroblast cell line could inhibit renal tumor growth in vivo. NIH/3T3 cells were transduced with retroviral vectors containing the murine endostatin (ES) gene. SCID mice bearing CaKi-1 derived tumors were given a subcutaneous injection of either ES-transduced cells or control cells and were monitored for tumor growth. At the end of the in vivo experiment, the mean tumor volume of treated mice was 51.6 +/- 2.4 mm3, while the tumor volume of control was 234.5 +/- 14.8 mm3. Microvascular density was significantly decreased on treatment (control 9.79 vs. ES 2.53%, <0.001) accompanied by a 23-fold increase in intratumoral necrotic area and a 2.94-fold increase in the apoptotic index, determined by immunohistochemistry with anti-activated caspase-3. Apoptotic cells were found in foci enriched in infiltrating leukocytes. In conclusion, retroviral endostatin gene transfer led to secretion of functional endostatin that was sufficiently active to inhibit tumor angiogenesis and tumor growth. A second mechanism may also be implied in endostatin-dependent tumor regression, associated with tumor infiltration of leukocytes. Besides its antiangiogenic properties, endostatin may be a promising adjuvant to immunotherapy.

Study of Blood Porphyrin Spectral Profile for Diagnosis of Tumor Progression

Renal cell carcinoma (RCC) accounts for approximately 3% of new cancer incidence and mortality in the United States. Unfortunately many RCC masses remain asymptomatic and nonpalpable until they are advanced. Diagnosis and localization of early carcinoma play an important role in the prevention and curative treatment of RCC. The autofluorescence of blood porphyrin of healthy and tumor induced in male SCID mice was analyzed using fluorescence and excitation spectroscopy. A significant contrast between normal and tumor blood could be established. Blood porphyrin fluorophore showed enhanced fluorescence band (around 630 nm) in function of the tumor growth. This indicates that either the autofluorescence intensity of the blood fluorescence may provide a good parameter for the "first approximation" characterization of the tumor stage.

S-phase reduction in T47D human breast cancer epithelial cells induced by an S100P antisense-retroviral construct

S100P is expressed in several malignant neoplasms. It was previously demonstrated that S100P is involved in the very early stages of breast carcinogenesis. In the present study we used a retrovirus-mediated transfer of antisense-S100P in order to check whether the decrease in expression of this protein could lead to alterations in the cell cycle of epithelial cells of human breast cancer. The T47D breast carcinoma cell line, a human breast epithelial cell that expresses high levels of S100P, was a tool used in this study to investigate the alteration in cell cycle induced by a retrovirus-mediated transfer of antisense-S100P. First we used the real-time PCR technique to quantify the gene expression. The results showed a reduction of 63% of expression within the T47D-S100P-A/S infected population compared with control T47D-LXSN clones. To determine the impact of the S100P antisense technique on protein expression in T47D cells, we performed immunofluorescence staining and analyzed the resulting images using a confocal microscope. The images showed much less pronounced antibody marking of the S100P protein in the T47D-S100P-A/S compared with control cells. To evaluate whether the antisense approach caused any alteration in the cell cycle, we concluded the study with flow cytometric analysis of the cell distribution. Our findings indicated that, in our model, S100P-antisense cells showed a 23% reduction of cells at the S-phase. Using transduction techniques with an S100P antisense-retroviral construct we were able to demonstrate a significant reduction in S-phase of the T47D cell cycle. To the best of our knowledge, this is the first time that an antisense approach has been used against S100P mRNA in breast cancer epithelial cells. The results showed here seem to further classify S100P as a protein that might be involved in the cell cycle imbalance observed during breast carcinogenesis.

Increases in weight of growth hormone‐deficient and immunodeficient (lit/scid) dwarf mice after grafting of hGH‐ secreting, primary human keratinocytes

Primary human keratinocytes, stably transduced with the human growth hormone (hGH) gene (under control of the retroviral LTR promoter) and selected via geneticin secreted as much as 7 microg hGH/106 cells/day. Their grafting onto immunodeficient dwarf mice (lit/scid) led to hGH levels in the circulation that did not go below 0.2-0.3 ng/ml during a 12 day period (peak value, 1.5 ng/ml at 4 h). This phenomenon was associated with a body weight increase of the grafted animals (0.060 g/animal/day) significantly higher (P<0.01) than that of controls (0.023 g/animal/day). This is the first report describing successful utilization of immunodeficient dwarf mice (lit/scid) in keratinocyte-based hGH gene therapy.

High-yield purification of biosynthetic human growth hormone secreted in Escherichia coli periplasmic space

A six-step, high-yield purification procedure for the preparation of clinical grade recombinant human growth hormone (rhGH) secreted in bacterial periplasmic space is described. Particular emphasis is given to hormone recovery yields and maximum contaminant host cell elimination. The strategy adopted, in addition to using one precipitation and five chromatographic steps in a particularly efficient sequence, was also based on running E. coli proteins - immunoradiometric assay profiles right after each chromatographic elution. Thus, an overall rhGH recovery higher than 40%, with a final concentration of E. coli proteins below 10 ppm is described for the first time. The accuracy of hGH and total protein quantification, especially in the early steps of the process, and the maximum elimination of hGH-related forms were also studied in detail. For these purposes size-exclusion and reversed-phase HPLC were found to be extremely valuable analytical tools.

Ultrasensitive in vivo bioassay detects bioactive human growth hormone in transduced primary human keratinocytes

An improved in vivo body weight gain bioassay for the potency determination of human growth hormone (hGH) has been set up in "little" mice (lit/lit), a mutant derived from the C57BL/6J strain. This improved assay now has a detection limit of the order of 0.05 micrograms/mouse/day, which corresponds to a sensitivity about 20-fold higher than that of the most sensitive in vivo assay reported up to now: the tibia test in hypophysectomized rats or mice. This sensitivity was achieved mainly by introduction of a careful pre-assay selection and of a three injections per day schedule. The utilization of these conditions in a 2x2 factorial assay design allowed the potency determination of recombinant DNA-derived hGH (rec-hGH) in bacterial extracts with acceptable accuracy and precision, together with the greatest economy of material, only 0.24 mg of unknown and standard hormone preparation being sufficient for an entire 10-animal assay. This contrasts to a minimum of 2.7 mg that are necessary for an economical assay in hypophysectomized rats. The same assay procedure was also used to demonstrate the in vivo bioactivity of hGH secreted into a culture medium from transduced human primary keratinocytes. The growth curve constructed with n = 8 little mice presented a highly significant correlation (r = 0.939, p < 0.001) and a slope = 0.016 g/mouse/day. It was thus possible to prove, for the first time, the in vivo bioactivity of rec-hGH secreted by transplantable human epidermal cells, utilized as an experimental model for somatic gene therapy.

In vivo bioassay for the potency determination of human growth hormone in dwarf "little" mice

Homozygous 40- to 90-day-old "little" mice (lit/lit), derived from the C57BL/6J strain, have been used to set up an in vivo body weight gain bioassay for GH whose performance has been compared to the widely used hypophysectomized rat assay. A log dose-response curve has been analyzed in order to choose doses in the linear range that are suitable for setting up useful, precise, and economical 2 x 2 factorial assays. A comparison between the response in the two sexes has also been carried out, showing no significant difference between male and female little mice of this age. Three assays have been carried out in these animals for the potency determination of a local human GH (hGH) reference preparation in terms of First International Standard of GH (human) for bioassay (WHO 80/505), comparing them to a classical assay in hypophysectomized rats performed with the same preparations. The calculated potency values were in good agreement, while the statistical parameters indicated a comparable assay precision, even in a practical and rapid 4-day assay. We suggest the substitution of hypophysectomized rats with little mice for this in vivo test, still required for potency and bioidentity determination of clinical preparations of recombinant hGH. This avoids the highly invasive, costly, and time-consuming surgery, providing a faster, more flexible, and economical assay method, while still directly measuring parameters of in vivo linear growth in an animal model closely related to isolated hGH deficiency type I.