ErbB4 increases the proliferation potential of human lung cancer cells and its blockage can be used as a target for anti-cancer therapy

Clinical and experimental data suggest that ErbB-4, a member of the epidermal growth factor receptor family, may have a role in cancer progression and response to treatment. We found recently, using a retrospective clinical analysis, that expression of ErbB-4 receptor is correlated with metastatic potential and patient survival in non-small-cell lung cancer (NSCLC). The purpose of this work was to correlate the expression of the ErbB-4 and lung cancer cells growth in vitro and in vivo and to determine the therapeutic potential of a monoclonal antibody to ErbB-4 against lung cancer. For this aim, we ectopically expressed ErbB-4 in a human NSCLC cell line that did not express the ErbB-4 protein. Overexpression of ErbB-4 produced a constitutively activated ErbB-4 receptor. The transfected ErbB-4 positive clones showed an increased cell proliferation in vitro and in vivo in comparison with parental ErbB-4 negative cells and with the cells transfected by neomycin-resistant gene. A monoclonal antibody to ErbB-4 showed both an inhibitory effect on growth rate and an increasing apoptotic rate in the cells expressing ErbB-4. The results of the current study provide evidence that ErbB-4 plays a significant role in human lung cancer and may serve as a molecular target for anticancer therapy.

ErbB1–4 expression in prostate cancer patients and its correlation to patients’ ethnicity and outcome

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Background: ErbB family is involved in both cancer progression and treatment response in solid tumors. Few inconclusive studies reported on ErbB over-expression in prostate cancer. We investigated ErbB1–4 expression in prostate cancer patients and its correlation to patients ethnicity and outcome. Methods: ErbB expression was evaluated by immunohistochemistry of prostate cancer specimen using polyclonal antibody (Santa Cruz, CA). The staining was recorded as negative (0/+1), moderately positive (+2) and highly positive (+3). Kattan nomogram was used to predict 5-yr progression-free probability, assuming that all patients received external beam radiation therapy (a total dose of 78 Gy) and hormonal manipulation. Origin was counted in all 43 patients: Ashkenazic patients were defined as those who immigrated from East/West Europe or North America and Sephardic patients - from Middle East and North Africa. Results: ErbB1 (+2/+3) was over-expressed in 12 and 7 patients for a total of 19/43 (44%). ErbB2 over-expression (+2/+3) was not found in all patients. ErbB3 over-expression of +2 was seen in 2 patients and none had +3 (2/43, 5%). ErbB4 over-expression (+2/+3) was seen in 5 and 11 patients for a total of 16/43 (37%). 22 patients were Ashkenazic and 21 - Sephardic. ErbB1 over-expression in Ashkenazic and Sephardic groups was 9/22 (41%) and 10/21 (48%). ErbB4 over-expression in the two groups was 7/22 (32%) and 9/21 (43%). Kattan score of <80 was seen in 20/43 and <60 in 7/43 patients. ErbB1 over-expression was noted in 11/20 and in 4/7 patients. ErbB4 over-expression was seen in 7/20 and in 4/7 patients. In both ErbB1 and ErbB4 over-expression and Kattan nomogram of <80 and <60 the Sephardic ethnicity dominated-7/11 (64%), 3/4 (75%), 5/7 (71%) and 3/4 (75%). Conclusions: ErbB1 and ErbB4 over-expression is presented in 43% and 37% patients while ErbB3 was over-expressed in 5%; no over-expression of ErbB2 was observed. Ashkenazic and Sephardic ethnicity were evenly distributed in the over-expressed ErbB1 and ErbB4 patients. However, a tendency to a worse prognosis, based on Kattan nomogram, was seen in over-expressed ErbB1 and ErbB4 patients from Sephardic ethnicity. Further studies on ethnicity and ErbB prevalence and prognosis are warranted.

No significant financial relationships to disclose.

Establishment and Characterization of a Pancreatic Carcinoma Cell Line Derived from Malignant Pleural Effusion

BACKGROUND/AIMS

A novel cell line, designated p34, was developed from the malignant pleural effusion of a patient with carcinoma of pancreas. The objective of this work was to characterize this cell line.

METHOD

The in vitro studies included karyotype analysis, immunohistochemistry, XTT cell proliferation assay, analysis of the cell cycle by FACS and cell sensitivity to chemotherapeutic drugs and irradiation. Subcutaneous and intra-spleen inoculations into nude mice were carried out to study the tumorigenicity and the metastatic tendency of this cell line.

RESULTS

The p34 cell line showed typical morphological characteristics of epithelial pancreatic tumor cells. The cells were hyperdiploid with a modal number of 48, and had two markers, deletion in the short arm of chromosome 2 and duplication of the short arm of chromosome 8. The doubling time was 16 h. Subcutaneous inoculation of the cells into nude mice yielded 100% tumorigenicity, and intra-spleen inoculation resulted in extensive intra-abdominal spread. The antiproliferative effect of chemotherapy (gemcitabine, cisplatin, taxol and vinorelbine), chemopreventive agents (celecoxib and curcumin) and radiotherapy showed dose-dependent cytotoxicity.

CONCLUSIONS

This p34 cell line can be used as a new model for studying various aspects of the biology of human pancreatic cancer and potential treatment approaches for the disease.

Establishing Schedules for Repeated Doses of Strontium and for Concurrent Chemotherapy in Hormone-Resistant Patients With Prostate Cancer

Strontium-89 (Sr-89) alone or with concurrent chemotherapy has a role in the treatment of patients with prostate cancer (PCP). The schedules for repeated doses of Sr-89 or for concurrent chemotherapy is undetermined. The objective of this study was to measure the effective half-life (Te) of Sr-89 using a detector available in a nuclear research facility. Blood and urine samples obtained from PCP treated with Sr-89 (Metastron, Amersham, U.K.) were measured for radioactivity with a High Pure Germanium (HPGe) detector in a gamma spectrometry system (Eurisys, France). Twenty-five urine and 22 blood samples were obtained from 8 patients during a period of 160 days after Metastron injection. Sr-89 radioactivity levels in blood and urine were quite low (<8.2 x 10(-3) microCi/mL) in all patients after 21 days, whereas Sr-85 (available in 0.5% of Metastron) urine and, to a lesser extent, blood radioactivity levels were moderately high and could be detected up to 160 days. Based on Sr-85 urine levels, the calculated Sr-89 Te ranged from 9.6 to 20.7 days. Sr-89 Te can be routinely calculated in PCP based on HPGe detection of Sr-85 radioactivity levels in urine. This measurement can establish schedules for either repeated doses of Sr-89 or concurrent chemotherapy.

Radiation therapy in cancer patients with psoriasis. The fractionated daily dose and the Koebner phenomenon

Skin side effects following XRT take place more often in patients with skin disorders. In this study six patients with psoriatic lesions were evaluated. The total/daily XRT dose to the tumor site was 50-70/1.8-2.0 Gy. No debilitating effect of XRT was observed in both the psoriatic lesions and in the surrounding normal skin.

Hyperthermia combined with radiation therapy in the treatment of local recurrent breast cancer

BACKGROUND

Hyperthermia combined with radiation therapy was shown to be more effective in local recurrent breast cancer than radiotherapy alone, but its use is limited due to technical difficulties, stringent reimbursement policies and because it is time consuming.

OBJECTIVES

To report our experience with a simple and convenient XRT + HT delivery system.

METHODS

XRT was delivered through either electron or photon beams (total dose 30-40 Gy in previously irradiated fields or 50-70 Gy in non-irradiated fields). Hyperthermia was delivered by a dedicated HT device operating at 915 MHz. The heating session lasted 45 minutes. The maximal tumor surface temperature was set at 45 degrees C and modified according to patient comfort. No intratumoral (invasive) thermometry was used. At least two HT sessions were scheduled to each HT field during the entire XRT treatment period. Tumor response was evaluated every 3 months after completion of treatment. The overall survival was measured from XRT + HT initiation until the last follow-up.

RESULTS

Fifteen women underwent 114 HT treatments delivered through 28 HT fields. Twenty-four HT fields (15 patients) were previously irradiated. There was complete infield response in 10 fields (6 patients), partial response in 8 fields (4 patients), no response or progressive disease in 4 fields (3 patients), and no parameters in 6 fields (5 patients). Eighteen fields (64%) had complete or partial response. Seven patients had outfield recurrence despite wide XRT + HT fields. Ulceration was the only major side effect (three patients, three fields).

CONCLUSIONS

The combined HT+XRT delivery system, with no invasive thermometry, is a simple and effective method for treating local recurrent breast cancer.

Liposome transduction into cells enhanced by haptotactic peptides (Haptides) homologous to fibrinogen C-termini

Haptides are 19-21mer cell-binding peptides equivalent to sequences on the C-termini of fibrinogen beta chain (Cbeta), gamma chain (preCgamma) and the extended alphaE chain of fibrinogen (CalphaE). In solution, Haptides accumulated in cells by non-saturable kinetics [Exp. Cell Res. 287 (2003) 116]. This study describes Haptide interactions with liposomes and Haptide-mediated liposome uptake by cells. Haptides became incorporated into negatively charged liposomes, changing their zeta potential. Atomic force microscopy and particle sizing by light scattering showed that the liposomes dissolved Haptide nanoparticles and absorbed them from solution. Pre-mixing fluorescent rhodamine-containing liposomes or "stealth" doxorubicin (DOX)-containing liposomes (Doxil) with Cbeta, preCgamma or to a lesser degree CalphaE, significantly enhanced their uptake by fibroblasts and endothelial cells. Confocal microscopy showed Haptide-induced liposome uptake saturated above approximately 40 microM Haptide. Cytotoxicity tests with lower concentrations of Doxil liposomes indicated that premixing with approximately 40 microM Cbeta or preCgamma increased their toxicity by one order of magnitude. It was evident that the liposomes complexed with an amphiphilic Haptide are transduced through cell membranes, probably by a non-receptor-mediated process. These results suggest that Cbeta or pre-Cgamma could be employed to augment the cellular uptake of drugs in liposomal formulations.

New cell attachment peptide sequences from conserved epitopes in the carboxy termini of fibrinogen

Fibrinogen seems to contribute significantly to cell binding and recruitment into wounds besides its major role in clot formation. We describe 19- to 21-mer cell-binding (haptotactic) peptides from the C-termini of fibrinogen beta-chain (Cbeta), the extended alphaE chain, and near the C-terminal of the gamma-chain. When these peptides were covalently bound to a biologically inert matrix such as Sepharose beads (SB), they elicited beads attachment to cells, mostly of mesenchymal origin (including fibroblasts, endothelial cells, and smooth muscle cells) as well as some transformed cell lines. Based on such haptotactic activity, these peptides were termed "haptides." By contrast, peptides homologous to fibrinogen C-termini alpha- and gamma-chains elicited no such activity. The haptide Cbeta could not block the interaction of fibroblasts with antibodies directed against integrins beta(1), alpha(v), alpha(v)beta(1), alpha(v)beta(3), and alphaIIbeta(3). Moreover, GRGDS peptide could not inhibit enhanced cell binding to SB-Cbeta, as expected from an integrin-mediated process. In soluble form the haptides were accumulated in cells with nonsaturable kinetics without any toxic or proproliferative effects in concentrations up to 80 microM. These findings suggest that the conserved haptidic sequences within fibrin(ogen) can be associated with the adhesion and migration of cells into fibrin clots and may have a significant role in normal wound healing and in various pathological conditions.

Fibrin microbeads for isolating and growing bone marrow-derived progenitor cells capable of forming bone tissue

It has been demonstrated that bone marrow (BM)-derived pluripotent stem cells can be incorporated into muscle, bone, nerve, lung, stomach, intestine, and skin. Fibrin-based biodegradable microbeads (FMB) were developed for culturing, in suspension, a high density of cells, mostly of mesenchymal origin. In the current study, FMB were used to isolate and expand mesenchymal progenitor cells from BM of mice and rats. Cells from BM isolated on FMB (FMB-BM cells) were visualized by fluorescent confocal microscopy and quantified by a modified MTS colorimetric assay. Downloading the BM cells from FMB onto plastic induced their differentiation into islets of cells with osteogenic phenotype that secreted mineralized extracellular matrix. This was augmented by inducers of osteogenesis, such as ascorbic acid, beta-glycerophosphate, and dexamethasone, or osteoblast-growth peptides (OGP). Implanting FMB-BM cells under the kidney capsule in mouse tested the osteogenic potential of these cells in vivo. Thirty days after implantation, bone structures with typical BM elements were seen in 8/53 kidneys in 6-Gy-irradiated mice and in 1/10 kidneys in nonirradiated recipients; bone formation was verified by soft x-ray imaging and elemental analysis that showed elevated Ca and Fe in the implant region. FMB-BM cells - downloaded onto plastic flasks, cultured for 2 weeks, mechanically harvested and then implanted - induced 100% bone formation in both irradiated (6/6) and nonirradiated (3/3) mice. Histology revealed well-organized bone structures under the kidney capsule, including osteoblasts and typical elements of BM. Our findings demonstrate that FMB are capable of isolating and expanding progenitor cells from BM for osteogenesis and possibly for regenerating other mesenchymal tissues.

Late effects of dose fractionation on the mechanical properties of breast skin following post-lumpectomy radiotherapy

PURPOSE

Late radiation-induced skin effects were studied in a multicenter project using our new sensitive noninvasive viscoelasticity skin analyzer (VESA).

METHODS AND MATERIALS

Skin viscoelasticity and anisotropy were examined quantitatively in symmetric areas of both breasts in healthy women and in 110 breast cancer patients who underwent lumpectomy and radiotherapy. These parameters were evaluated by the VESA measurement of the speed of elastic wave propagation in the skin; higher VESA readings correspond to higher skin stiffness. Effect of radiation was estimated by comparison of the data recorded in the irradiated versus nonirradiated breast of the same patient.

RESULTS

Skin viscoelasticity and anisotropy were similar in contralateral areas of the breasts in healthy controls as well as in the nonirradiated breasts of the patients. With age, skin viscoelasticity decreased and anisotropy increased similarly in both breasts. Radiotherapy, by a total radiation dose in the range of 45-50 Gy given with 1.8 Gy/fraction (fx) resulted in a similar minor, but still statistically significant, increase of skin stiffness relative to control. The effect was more pronounced when a dose of 50 Gy was given in a higher dose/fraction of 2.5 Gy.

CONCLUSION

We found that the increase in dose of radiation per fraction had much more impact on the development of late skin effects than elevation in the total dose given.

Measurement of breast skin viscoelasticity and a pilot study on the potential radioprotective effect of a zinc-based cream

Radiation-induced late skin effects were studied in patients with breast cancer in relation to different protocols of fractionated radiotherapy in three different medical centres, in Israel, the UK and the USA. The mechanical properties of skin were evaluated in breasts of healthy volunteers, and non-irradiated and irradiated breasts of patients, using a newly developed viscoelasticity skin analyser (VESA). The increase of the dose of radiation per fraction was found to have more impact on the development of radiation-induced late skin effects than the elevation of the total dose given. In addition, a pilot study on the possible radioprotective effect of external application of a cream containing zinc oxide on radiation-induced early skin changes in patients with breast cancer was initiated. Non-invasive measurement of trace elements and zinc pharmacokinetics in the skin of healthy controls following the application of the zinc oxide cream were performed by unique diagnostic X-ray spectrometry (DXS). Application of the cream, followed by thorough skin cleansing, significantly increased the amount of residual zinc in the skin, but continuous daily treatment did not cause further build-up of the dermal zinc level. The radioprotective effect of the zinc oxide cream on the skin is now being studied.

Evaluation of skin viscoelasticity and anisotropy by measurement of speed of shear wave propagation with viscoelasticity skin analyzer

Skin viscoelasticity was evaluated by a fast, noninvasive assay based on the measurement of the speed of elastic shear wave propagation in the skin by a new portable and user-friendly viscoelasticity skin analyzer. The range of speed of elastic shear wave propagation measured by viscoelasticity skin analyzer allows the evaluation of the stiffness of a wide spectrum of artificial materials as well as the viscoelasticity of skin of laboratory animals and human subjects. The directional nature of the measurement enables to monitor the anisotropy of the materials tested. The speed of elastic shear wave propagation was shown to have a positive correlation with the stiffness of the material tested. In symmetric contralateral areas of intact skin in rabbit ears, similar viscoelasticity and anisotropy were observed. Twenty-four hours after the induction of local edema by croton oil, skin stiffness and anisotropy were significantly increased. In healthy human subjects of both sexes significant variations in skin stiffness and anisotropy were observed in three different skin areas along the forearms, but the speed of elastic shear wave propagation was similar in the symmetric contralateral areas. Age (17-65 y) seemed to have a limited effect on the viscoelasticity of the forearm skin. Hydrating creams decreased the stiffness of the forearm skin for only approximately 3 h. The stiffness and anisotropy of the skin of the breasts in female volunteers (20-86 y) increased with age, but the speed of elastic shear wave propagation was similar in symmetric contralateral areas in the same individuals. Based on these results, we propose the application of the viscoelasticity skin analyzer in experimental and clinical practice for quantitative evaluation of skin condition.

Fibrin microbeads (FMB) as biodegradable carriers for culturing cells and for accelerating wound healing

We have developed biodegradable fibrin-derived microbeads as potent cell carriers. The fibrin-derived microbeads, 50-200 microm in diameter, were tested for their attachment to a wide range of cell types. Fibrin-derived microbeads were shown to be greatly haptotactic to cells (such as endothelial cells, smooth muscle cells and fibroblasts), which respond to fibrinogen in contrast to keratinocytes and different cell lines derived from leukocytic lineage. The cells on fibrin-derived microbeads could be maintained for more than 10 d and achieved a high density. 31P-nuclear magnetic resonance was employed to monitor phosphate metabolism in cells, with densities on the order of 100 million cells per g of fibrin-derived microbeads. The 31P-nuclear magnetic resonance adenosine triphosphate and phosphocreatine signals, equivalent to the signal obtained with perfused normal skin, indicated that metabolism of cells on fibrin-derived microbeads was responsive to oxygenation and nutrients. Light, fluorescent, and confocal laser microscopy revealed that the porous fibrin-derived microbeads accommodate up to 200-300 cells due to their high surface area which minimized contact inhibition. Cells could degrade the fibrin-derived microbeads and be transferred to seed culture flasks without trypsinization. In a pig skin wound healing model, fibrin-derived microbeads + fibroblasts were transplanted into full thickness punch wounds. This procedure was compared with other treatment modalities, such as the addition of human platelet-derived growth factor BB or fibrin-derived microbeads alone. By the third day after wounding, only the wounds in which fibroblasts on fibrin-derived microbeads were added showed significant formation of granulation tissue. Based on the above, we project many uses of our novel fibrin-derived microbead technology for cell culturing, wound healing and tissue engineering.

Chronic graft-versus-host disease treated with UVB phototherapy

Chronic graft-versus-host disease (cGVHD) is a major complication of allogeneic bone marrow transplantation. Immunosuppressive treatment regimens carry the potential of causing severe morbidity and mortality, so that additional modes of therapy with fewer side-effects are clearly needed. Five cGVHD patients (sclerodermoid cGVHD in two patients, lichenoid cGVHD in one patient and intraoral cGVHD in two patients), who had not responded to standard immunosuppressive drugs, were treated with adjuvant UVB phototherapy. The patient with lichenoid cGVHD experienced complete clearing of cutaneous lesions, whereas both patients with sclerodermoid cGVHD experienced significant relief of pruritus, but showed no change of the sclerodermoid skin lesions. Intraoral lesions cleared in one patient. The effects of UVB phototherapy were furthermore documented by measurement of skin viscoelasticity and mouth opening. No side-effects were encountered. This preliminary study suggests that UVB phototherapy is useful as an adjuvant therapeutic modality in intraoral and cutaneous lichenoid cGVHD.

Paclitaxel-induced modification of the effects of radiation and alterations in the cell cycle in normal and tumor mammalian cells

The cytotoxicity of paclitaxel (taxol) is associated mainly with block in G2/M phase, the most radiosensitive phase of the cell cycle. Nevertheless, taxol-induced modification of the effects of radiation may vary from clear sensitization to subadditivity. Therefore, this effect was studied in relation to drug-induced alterations in the distribution of cells in the phases of the cell cycle in tumor cells (EMT-6 and OV-1063) and normal skin fibroblasts. Cell survival was evaluated with two colorimetric assays. The cell cycle was evaluated by FACS analysis of doubly-labeled cells. The radiosensitivity of the different cells studied was similar, apart from the less radiosensitive human fibroblasts. However, their dose- and time-dependent sensitivity to taxol varied significantly. After 24 h exposure of EMT-6 cells to taxol (IC50 approximately 20 nM), the fraction of cells in G2/M phase increased, the fraction in S phase decreased, and the proportion of possibly apoptotic cells with subdiploid and subtetraploid DNA content increased; this coincided with radiosensitization. In OV-1063 cells (IC50 approximately 3 nM), the drug-induced G2/M-phase block was most pronounced, but the combined effect with radiation was merely additive. In human fibroblasts (IC50 approximately 35 nM), a minimal G2/M-phase block with no change in the S phase and a massive elevation of apoptotic cells with subdiploid DNA content was accompanied by a subadditive combined effect with radiation. Six hours of exposure to taxol increased the fraction of cells in S phase in both nonsynchronized and S-phase-synchronized human fibroblasts (G1 phase approximately 65%, S phase approximately 13%). This was accompanied by a pronounced subadditive effect of the combined treatment. However, in G1-phase synchronized human fibroblasts (G1 phase > or =90%, S phase approximately 3%), only the fraction of cells in G2/M phase was slightly elevated, with a merely additive response to the combined treatment. The differences in the response to the combined treatment between slowly and rapidly proliferating cells in relation to modifications in the cell cycle are discussed.

Haptotactic and growth stimulatory effects of fibrin(ogen) and thrombin on cultured fibroblasts

We tested the ability of purified, ultraviolet C virally inactivated components of human fibrin sealant (FS) to modulate the chemotaxis, adherence, and proliferation of cultured cells. A fibrin clot formed on a near-confluent layer of human fibroblasts (HFs) recruited cells from the surrounding area. Thrombin (Thr) enhanced HF proliferation by a factor of 1.5 to 1.8, whereas fibrinogen (Fib) exerted only a minimal proliferative effect. We developed a new cell haptotactic/attachment assay by using Thr and Fib covalently bound to Sepharose beads (SBs). The kinetics of cell binding were approximately equivalent for beads coated with either protein. Uncoated SBs or fibrinogen-bound SBs (Fib-SB) pretreated with plasmin did not attract HFs. AlphaThr-SB induced a positive migratory response that was not affected by blocking its proteolytic site, whereas gammaThr-SB elicited no response. X irradiation of HFs at a dose of 6 Gy showed that the migratory response of HF is independent of proliferation, as confirmed by a bromodeoxyuridine uptake assay. Several types of cultured cells (murine fibroblasts, smooth muscle cells, aortic endothelial cells, and murine mammary carcinoma cells) also attached to Fib-SB. By contrast, human keratinocytes, human ovarian carcinoma cells, murine macrophage-like cells, leukemic cells, and murine mast cells did not attach. Our results provide some mechanistic insights into the haptotactic and proliferative effects of Fib and Thr on different cells.