Incidence Of Tumor Growth Research Articles

Predicting Potential of Rapid Tumor Growth in Small to Medium Vestibular Schwannomas on the Basis of Sway Assessed Using Posturography

The relationship between quantitative posturography results and growth of vestibular schwannomas (VSs) during conservative management has not been studied. We aimed to clarify the relationship between the presence of disequilibrium based on posturographic measurement and VS growth. This retrospective, single-center study included 53 patients with VSs (Koos stage I or II) managed conservatively after initial diagnosis. Radiographic progression was considered present if 20% volumetric growth was observed over the imaging interval. Posturography was performed at initial diagnosis, and sway velocity (SV) and sway area were calculated. Tumor growth-free survival was estimated using the Kaplan-Meier method. Mean follow-up period was 2.87 ± 2.58 years, up to tumor growth detection or last follow-up magnetic resonance imaging. Tumor growth incidence was 40.8% and 61.2% at 2 and 5 years, respectively. Cerebellopontine angle extension and SV with eyes open were related to tumor growth. Tumor growth-free survival of patients with cerebellopontine angle extension and patients with intracanalicular tumor at 2 years was 37.3% and 76.4%, respectively. Tumor growth-free survival of patients with SV >2.06 cm/second and patients with SV ≤2.06 cm/second at 2 years was 30.8% and 68.9%, respectively. The Cox hazard model demonstrated a significant risk for future tumor growth with SV >2.06 cm/second (relative risk, 2.475; 95% confidence interval, 1.11-5.37, P= 0.027). We demonstrated a positive correlation between SV with eyes open and future tumor growth. Posturographic data are objective and quantitative; thus, SV may be a potential predictor of future growth of VSs.

Abstract 4236: Comparison of optical imaging approaches in 2D and 3D in disseminated mouse tumor models

Abstract Introduction: Optical imaging allows staging and tracking of multiple tumors in disseminated tumor models and to this end, bioluminescence (BLI) imaging has been the most common approach. While BLI is cost effective and quantitative, it requires luciferase-engineered tumor lines, which have the disadvantages of time and uncertainty associated with transfection, as well as potential phenotype change in the engineered line, compared with the parent. Exogenous fluorescence probes preferentially activated by tumors provide a similar efficient optical imaging means to tumor burden tracking in these models, directly in any tumor lines of interest. This methods also allows 3D imaging through new tomographic optical imaging technologies. In this work, BLI and activated fluorescent probe imaging were used in a luciferase-expressing Raji-luc human Burkitt's lymphoma model and an M-NFS-60 mouse leukemia model. 2D fluorescence reflectance imaging was also compared to 3D tomographic imaging to determine additional utility of the 3D imaging approach. Methods: Raji-luc lymphoma cells were transfected to express luciferase using a lentiviral vector transfection method. Raji-luc cells (1x107 cells in 100µl PBS) were injected IV in CB-17 mice on Day 0. In CD-1 mice, M-NFS-60 leukemia cells (1x107 cells in 100µl PBS) were injected IP. Bioluminescence scans were used to determine the distribution of light throughout the body immediately following implantation. In vivo and ex vivo bioluminescence imaging was used to localize tumor signals and determine incidence and tumor growth. Both cathepsin- (ProSense) and MMP- (MMPSense) activated fluorescent probes were injected IV 24h prior to fluorescence reflectance and fluorescence molecular tomographic imaging. Results and Discussion: Bioluminescence imaging of intravenously injected of Raji-luc cells from one to four weeks after inoculation showed a high incidence of tumor growth at sites including hind limbs, spine, and brain in addition to lung and to a lesser extent, the axillary lymph nodes and sternum. Fluorescence imaging with tumor activated probes provided a measure of disseminated tumor burden, but had the disadvantage of normal tissue background, compared with BLI where there was inherently no normal tissue background. Fluorescence molecular tomographic imaging provided a quantitative advantage over 2D fluorescence reflectance. Activated fluorescent probe imaging provides a viable means for imaging in disseminated tumor models without the need for engineered cell lines. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4236. doi:1538-7445.AM2012-4236

GROWTH AFTER RUBBING BY TUMOR CUT SURFACE: COMPARATIVE STUDY BETWEEN THREADWIRE SAW-CUT AND BLUNTLY-CUT TUMORS

Spondylectomy for extripation of spinal tumors would be performed through piecemeal excision or by total en bloc spondylectomy with cutting at the neural arch by the threadwire saw (T-saw) that is sometimes inevitably intralesional. The purpose of this study was to compare the potential for tumor growth after rubbing of the cut surface of tumors cut by either T-saw or blunt instrument against the subcutaneous tissues of nude mice. Tumors were prepared by subcutaneous injection of human HT 1080 fibrosarcoma cells in nude mice. The animals were sacrificed, and tumors were harvested en bloc and cut with either a T-saw or artery forceps. A 3-cm wound was created on the backs of other (plain) nude mice. The tumor's cut surface was rubbed for 10 seconds against the subcutaneous tissue of one of these nude mice. The wounds were then sutured. Tumor blocks were inoculated into other nude mice. Nude mice were followed for occurrence of tumor growth. Tumor growth occurred in all nude mice after block inoculation. The incidence of tumor growth after rubbing with the tumor surfaces cut with T-saw and artery forceps were 16.7% and 58.3% respectively (P = 0.035). Onset of tumor growth after tumor rubbing and inoculation of tumor blocks were 30.1 ± 25 and 12.2 ± 5 days respectively (P = 0.015). Rubbing of T-saw-cut tumor surface has less possibility of causing tumor growth than rubbing of surface of bluntly-cut tumors.

Tumor growth potential after tumoral and instrumental contamination: an in-vivo comparative study of T-saw, Gigli saw, and scalpel

In the field of spinal tumors, intralesional tumor cutting is sometimes inevitable. The purpose of this study was to compare the potential for tumor growth after intralesional cutting by T-saw, Gigli saw, and scalpel. Tumors, prepared by the subcutaneous injection of human HT 1080 fibrosarcoma cells in nude mice, were harvested and cut with a T-saw, Gigli saw, or scalpel. A 3-cm wound was created in the skin on the back in another group of nude mice. The cut surface of the tumor was rubbed for 10 s against the subcutaneous tissue in this second group of nude mice. In the same manner, the instrument used for tumor cutting was rubbed against the subcutaneous tissue in the 3-cm wound in the back of a third group of nude mice for 10 s. Other instruments used for tumor cutting were immediately washed in culture medium, and the total number of tumor cells was counted. Tumor blocks and single-cell suspensions prepared from tumor tissues of the same weight were inoculated and injected into a fourth group of nude mice. The incidence of tumor growth after the rubbing of the subcutaneous tissue with the tumor surface cut with a T-saw, Gigli saw, and scalpel was 16.7%, 50.0%, and 33.3%, respectively. The corresponding figures after the rubbing of the subcutaneous tissue with a T-saw, Gigli saw, and scalpel was 16.7%, 33.3%, and 33.3%, respectively. The mean numbers of tumor cells attached to the T-saw, Gigli saw, and scalpel were 1.88 X 105, 5.02 X 105, and 4.92 X 105, respectively. Finally, the incidence of tumor growth after the inoculation of tumor blocks and single-cell suspensions was 100% and 77.8%, respectively. These findings show that tumor recurrence is less likely after intralesional tumor cutting with a T-saw than after such cutting with a Gigli saw or scalpel.

Ocular melanoma

An experimental model is suggested for reproducing ocular melanoma in New Zealand white rabbits using B16 melanoma cells and protocols differing with respect to either tumour origin (subcutaneous fragments of melanoma B16 or B16-F10 tumour cell cultures) or implant site (the anterior chamber or subchoroidal). In 20 animals, 20 mg of methylprednisolone acetate was injected subconjunctivally as a local immunosuppressant. The only protocol resulting in tumour was inoculation of 4 x 10(6) B16-F10 melanocytes into the anterior chamber of the eye. Trans-scleral injections of cell suspensions produced tumour growth in 43% (13/30) of animals so treated. Thirteen animals developed non-neoplastic pigmented lesions formed of numerous melanophages. Another 19 animals showed non-pigmented lesions caused by reaction to the surgical procedures. Subconjunctivally injected methylprednisolone acetate did not increase the incidence of tumour growth.

Facilitation by partial hepatectomy of tumor growth within the rat liver following intraportal injection of syngeneic tumor cells

The effects of both mechanical trauma and regeneration on the growth of intraportally injected tumor in the rat liver were investigated using two-thirds partial hepatectomy (PH). Tumor grew at the excision scar when PH was performed less than 2 days before tumor injection (34/34 animals). However, when the PH was performed 4-7 days before injection, tumor developed within the regenerating lobe, but not at the scar (50/51). Injecting the same cell dose into rats with intact livers caused few tumors to develop in 12/30 animals. Intraportally injected 51Cr-labelled tumor cells distributed uniformly in the liver irrespective of the time after PH. Patterns of tumor take seen at different times after PH were not due to selective trapping of the injected cells. Liver extracts showed that epidermal growth factor-like activity was unaltered by PH, while heparin-binding growth factor activity peaked at 2 days post-PH, before the incidence of tumor growth in the parenchyma increased. We observed two peaks of DNA synthesis at days 1 and 4 post-PH by pulse labeling with [125I]deoxyuridine and bromodeoxyuridine. Bromodeoxyuridine immunohistochemistry showed the first peak to be confined to hepatocytes. The second peak involved non-hepatocytes and coincided with the beginning of enhanced tumor take in the regenerating lobe.

Retention of endocrine function by an insulin-secreting pancreatic islet cell tumour from syrian hamster through serial transplantation in Nude mice

An insulin-secreting islet cell tumour of the Syrian hamster has been transplanted serially in the congenitally immune-deficient nude mouse, in order to test the potential usefulness of this mouse mutant as a graft carrier of heterologous tumours with stable differentiated phenotypes. The incidence of tumour growth was very high, and the hamster tumour retained its functional and histologic characteristics during consecutive passages in nude mice. These results show that nude mice may be useful carriers of differentiated tumours from non-inbred species including man, and for the isolation of cell lines from such tumours.

Brain tumor types induced by the Schmidt-Ruppin strain of Rous sarcoma virus in inbred Fischer rats.

The Schmidt-Ruppin strain of Rous sarcoma virus has been shown to induce neuroectodermal and mesenchymal tumors of the brain of inbred CDF Fischer rats. The inoculation of 105 FFU of virus into the cerebrum of 2 day old rats was followed by 96% incidence of tumor growth after a latency period of 3 months. Twenty-four of twenty-five inoculated animals developed tumors, all of which were primary intracerebral neoplasms. They fell into three main groups: gliomas 60%, sarcomas 31%, gliosarcomas 9%. Of the 34 gliomas induced, 28 (84%) were astrocytic, and there was one oligodendroglioma, 2 mixed gliomas, and 3 ependymoma-like tumors. The advantages of this brain tumor model are a high glioma incidence, and a short induction time in a commercially available strain of inbred Fischer rats previously shown to be susceptible to the neuro-oncogenic action of resorptive chemical carcinogens.

Enhancement of the growth of sarcoma 180 in splenectomized and sham-operated AKR mice.

Sarcoma 180 (S-180) grows in 0–10% of AKR mice. The incidence of tumor growth is increased in animals implanted 3 weeks previously with another graft of this tumor. This increase in incidence of growth is prevented by splenectomy. Similarly, treatments with frozen-thawed homogenates of S-180 greatly

Chromosome Conditions of Hypodiploid Moloney Virus-Induced Mouse Leukemia, Its Transplantability and Inductivity

Moloney virus-induced leukemia of BALB/c mice became transplantable in adult C3H mice after 2 successive transplant generations in suckling mice of the same strain. Cells with 39 chromosomes served as a stemline for the growth of the transplantable leukemias in the C3H mice. Thirty-nine mice were examined from the third through the sixteenth transplant generation, and a high percentage of the cells derived from their thymuses, spleens, and mesenteric lymph nodes, and livers showed predominantly 39 acrocentric chromosomes. Karyotype analyses revealed a depletion of 1 chromosome from the 40-chromosome complement of the control tissues. In 14 isologous whole-cell transplantations in C3H mice, 77% of 203 recipient hosts developed leukemias. Homologous transplantations of these leukemic cells in adult mice of the BALB/c, DBA, Rlll, and Swiss strains were negative. Only newborn Swiss mice developed the disease, and cells from their leukemic tissues showed 39 chromosomes. Evidence was presented that the transplantable leukemic cells contained virus; these cell-free extracts from the leukemic tissues of BALB/c mice of the second transplant generation induced the disease in Swiss mice inoculated at birth. The incidence of tumor growth was 92% (12/13), and the latent period, ranging from 9–30 weeks, averaged 16 weeks. In spleen cells of the cell-free, extract-induced leukemias of Swiss mice, the modal number of chromosomes was 40–41.

Comparison of the effect of plasmapheresis and penicillamine on the level of circulating rheumatoid factor.

It has been shown previously that slight elevations in serum levels of insulin-like growth factor-I (IGF-I) are correlated with an increased risk for developing prostate, breast, colon, and lung cancer. The aim of this study was to determine the role of serum IGF-I levels in the process of stimulating tumor growth and metastasis in a mouse model of colon cancer. Colon 38 adenocarcinoma tissue fragments were orthotopically transplanted by attachment to the surface of the cecum in control and liver-specific IGF-I-deficient (LID) mice in which serum IGF-I levels are 25% of that in control mice. A total of 156 male mice at 5 weeks of age (74 control mice and 82 LID mice) received tumor transplants. Mice were divided randomly into two groups; one group was injected i.p. with recombinant human IGF-I (2 mg/kg) twice daily for 6 weeks, and the other group received saline injections. IGF-I treatment increased the serum levels of IGF-I and IGFBP-3 in both control and LID mice. In the saline-injected group, the incidence of tumor growth on the cecum as well as the frequency of hepatic metastasis was significantly higher in control mice as compared with LID mice. Both control and LID mice treated with recombinant human IGF-I displayed significantly increased rates of tumor development on the cecum and metastasis to the liver, as compared with saline-injected mice. The number of metastatic nodules in the liver was significantly higher in control mice as compared with LID mice. The expression of vascular epithelial growth factor (VEGF) as well as vessel abundance in the cecum tumors was dependent on the levels of serum IGF-I. This study supports the hypothesis that circulating IGF-I levels play an important role in tumor development and metastasis.