Diffusion Magnetic Resonance Imaging: An Imaging Treatment Response Biomarker to Chemoradiotherapy in a Mouse Model of Squamous Cell Cancer of the Head and Neck

For the treatment of squamous cell cancer of the head and neck (SCCHN), the assessment of treatment response is traditionally accomplished by volumetric measurements and has been suggested to be prognostic for an eventual response to treatment. An early evaluation response during the course of radiation therapy could provide an opportunity to tailor treatment to individual patients. Diffusion magnetic resonance imaging (MRI) allows for the quantification of tissue water diffusion values, thus treatment-induced loss of tumor cells will result in the increase in water mobility at the microscopic level, which can be detected as an increase in tumor diffusion values before any volumetric changes occur. We evaluated the use of diffusion MRI as an imaging biomarker of treatment response in an orthotopic mouse model of SCCHN. Mice with murine squamous cells expressing the yeast transgene cytosine deaminase were treated with 5-fluorocytosine (5FC), ionizing radiation, and combined therapy and were compared with control animals both during and after treatment for changes in tumor volumes, diffusion values, and survival. Radiation therapy had minimal effect on volumetric growth rate, diffusion, or survival. Although 5FC and combination treatment resulted in similar reductions in tumor volumes, the combination treatment elicited a much greater increase in tumor diffusion values, which correlated with improved survival. Thus, diffusion MRI as an imaging biomarker has a potential for early evaluation of the response to chemoradiation treatment in SCCHN.     

The Combination of a Low-Dose Chemotherapeutic Agent, 5-Fluorouracil,and an Adenoviral Tumor Vaccine Has a Synergistic Benefit on Survival in a Tumor Model System

Standard cancer therapies, particularly those involving chemotherapy, are in need of modifications that both reduce short-term and long-term side effects as well as improve the overall survival of cancer patients. Here we show that combining low-dose chemotherapy with a therapeutic vaccination using an adenovirus encoding a model tumor-associated antigen, ovalbumin (Ad5-OVA), had a synergistic impact on survival in tumor-challenged mice. Mice that received the combinatorial treatment of Ad5-OVA plus low-dose 5-fluorouracil (5-FU) had a 95% survival rate compared to 7% and 30% survival rates for Ad5-OVA alone and 5-FU alone respectively. The presence of 5-FU enhanced the levels of OVA-specific CD8⁺ T lymphocytes in the spleens and draining lymph nodes of Ad5-OVA-treated mice, a phenomenon that was dependent on the mice having been tumor-challenged. Thus 5-FU may have enhanced survival of Ad5-OVA-treated mice by enhancing the tumor-specific immune response combined with eliminating tumor bulk. We also investigated the possibility that the observed therapeutic benefit may have been derived from the capacity of 5-FU to deplete MDSC populations. The findings presented here promote the concept of combining adenoviral cancer vaccines with low-dose chemotherapy.     

Therapeutic effect of genetically modified human neural stem cells encoding cytosine deaminase on experimental glioma

The aim of this study was to determine the efficacy of neural stem cell-based suicidal gene therapy in rats bearing human glioma. F3 human neural stem cells (NSCs) were transduced to encode cytosine deaminase (CD) which converts 5-fluorocytosine (5-FC) to 5-fluorouracil (5-FU). Intratumoral or intravenous transplantation of F3.CD human NSCs led to marked reduction in tumor burden and significantly prolonged the survival of brain tumor-bearing rats. The systemic administration of 5-FC with direct intratumoral/intravenous transplantation of F3.CD cells had remarkable therapeutic effect in rats with human glioma cells as compared with transplantation of parental F3 cells. There was 74% reduction in tumor volume in rats receiving direct transplantation of F3.CD cells into tumor site, and 67% reduction in tumor volume in rats receiving intravenous injection of F3.CD cells as compared to control animals transplanted with human glioma U373 cells alone. The combination of F3.CD and 5-FC was a highly effective in the glioma rat model. Our observations suggest that genetically engineered NSCs encoding suicide gene CD could provide clinical application of suicide gene therapy for patients with glioma.     

Enhanced therapeutic anti-tumor immunity induced by co-administration of 5-fluorouracil and adenovirus expressing CD40 ligand

Bystander immune activation by chemotherapy has recently gained extensive interest and provided support for the clinical use of chemotherapeutic agents in combination with immune enhancers. The CD40 ligand (CD40L; CD154) is a potent regulator of the anti-tumor immune response and recombinant adenovirus (RAd)-mediated CD40L gene therapy has been effective in various cancer models and in man. In this study we have assessed the combined effect of local RAd-CD40L and 5-fluorouracil (5-FU) administration on a syngeneic MB49 mouse bladder tumor model. Whereas MB49 cells implanted into immunocompetent mice responded poorly to RAd-CD40L or 5-FU alone, administration of both agents dramatically decreased tumor growth, increased survival of the mice and induced systemic MB49-specific immunity. This combination treatment was ineffective in athymic nude mice, highlighting an important role for T cell mediated anti-tumor immunity for full efficacy. 5-FU up-regulated the expression of Fas and immunogenic cell death markers in MB49 cells and cytotoxic T lymphocytes from mice receiving RAd-CD40L immunotherapy efficiently lysed 5-FU treated MB49 cells in a Fas ligand-dependent manner. Furthermore, local RAd-CD40L and 5-FU administration induced a shift of myeloid-derived suppressor cell phenotype into a less suppressive population. Collectively, these data suggest that RAd-CD40L gene therapy is a promising adjuvant treatment to 5-FU for the management of bladder cancer.     

In Vitro and In Vivo Effect of 5-FC Combined Gene Therapy with TNF-α and CD Suicide Gene on Human Laryngeal Carcinoma Cell Line Hep-2

This study was aimed to investigate the effect of combined cancer gene therapy with exogenous tumor necrosis factor-alpha (TNF-α) and cytosine deaminase (CD) suicide gene on laryngeal carcinoma cell line Hep-2 in vitro and in vivo. Transfection of the recombinant eukaryotic vectors of pcDNA3.1 (+) containing TNF-α and/or CD into Hep-2 cells resulted in expression of TNF-α and/or CD gene in vitro. The significant increase in apoptotic Hep-2 cells and decrease of Hep-2 cell proliferation were observed using 5-FC treatment combined with TNF-a expression by CD/5-FC suicide system. Moreover, bystander effect was also observed in the TNF-α and CD gene co-expression group. Laryngeal squamous cell carcinoma (LSCC) mice model was established by using BALB/c mice which different transfected Hep-2 cells with pcDNA3.1 (+) containing TNF-α and/or CD were applied subcutaneously. So these mice are divided into four groups, namely, Hep-2/TIC group; Hep-2/CD group; Hep-2/TNF-α group; Hep-2/0 group. At day 29 after cell inoculation, volume of grafted tumor had significant difference between each two of them (P<0.05). These results showed that the products of combined CD and TNF-α genes inhibited the growth of transplanted LSCC in mice model. So by our observed parameters and many others results, we hypothesized that 5-FC combined gene therapy with TNF-αand CD suicide gene should be an effective treatment on Laryngeal carcinoma.     

健脾化瘀中药提高胞嘧啶脱氨酶/单纯疱疹病毒胸苷激酶基因治疗肝细胞癌的实验研究

目的:观察健脾化瘀中药提高胞嘧啶脱氨酶/单纯疱疹病毒胸苷激酶基因治疗肝细胞癌的作用。方法:脂质体lipofectamine将含有双自杀基因的腺病毒载体pAd-CD/TK导人293细胞,收集病毒上清转染人肝癌细胞BEL7402,MTT法测定BEL7402细胞存活率。裸鼠人肝癌模型转染CD/TK双自杀基因后,给予5-FC500mg/kg,GCV 100mg/kg腹腔注射,同时予健脾化瘀中药960复方灌胃。观察肿瘤生长情况。结果:给予前体药物5-FC和GCV后,CD/TK转染细胞被杀死。并表现出较强的旁观者效应。转染细胞比例达到10%即表现出较强的杀伤作用(P<0.01)。健脾化瘀中药960复方具有提高旁观者效应作用,1.67ml/kg和2.5ml/kg960复方含药血清组细胞存活率显著低于对照组(P<0.01)。转染基因组应用5-FC和GCV治疗后,裸鼠肝癌的生长明显受到抑制(P<0.05),抑瘤率39.42%,单用中药组抑瘤率18.04%,中药与CD/TK 5-FC/GCV联合运用组,较单纯CD/5-FC/HSV-tk/GCV对裸鼠肿瘤模型的生长抑制作用更加明显(P<0.05),抑瘤率55.10%。结伦:腺病毒介导CD/TK自杀基因可有效地杀死人肝癌BEL7402细胞,健脾化瘀中药960复方具有显著提高CD/TK双自杀基因对人肝癌细胞的抑杀作用。     

Increased lymphocyte infiltration in patients with head and neck cancer treated with the IRX-2 immunotherapy regimen

Twenty-seven subjects with squamous cell cancer of the head and neck received the neoadjuvant IRX-2 immunotherapy regimen prior to surgery in a Phase 2 trial. Pretreatment tumor biopsies were compared with the primary tumor surgical specimens for lymphocyte infiltration, necrosis and fibrosis, using hematoxylin and eosin stain and immunohistochemistry in 25 subjects. Sections were examined by three pathologists. Relative to pretreatment biopsies, increases in lymphocyte infiltration (LI) were seen using H and E or immunohistochemistry. CD3+ CD4+ T cells and CD20+ B cells were primarily found in the peritumoral stroma and CD3+ CD8+ T cells and CD68+ macrophages were mainly intratumoral. LI in the surgical specimens were associated with reductions in the primary tumor size. Improved survival at 5?years was correlated with high overall LI in the tumor specimens. Neoadjuvant IRX-2 immunotherapy regimen may restore immune responsiveness presumably by mobilizing tumor infiltrating effector lymphocytes and macrophages into the tumor.     

Low Dose Fractionated Radiation Potentiates the Effects of Taxotere in Nude Mice Xenografts of Squamous Cell Carcinoma of Head and Neck

This study evaluated the combined effect of Low Dose Fractionated Radiation (LDFRT) and Taxotere (TXT) therapy on the growth of SCCHN (squamous cell carcinoma of head and neck; SQ-20B, a p53 mutant SCCHN cell line) tumors in a nude mouse model to exploit the increased hyper radiation sensitivity (HRS) phenomenon present in G2M cell cycle phase when induced by low doses of radiation that was demonstrated in in-vitro settings. Seventy-eight animals were randomized into one control group and 5 treatment groups (treatments were administered weekly for six weeks). Tumor regression was observed in all the groups, however, tumor regression was not significant in 2 Gy or TXT or 2 Gy plus TXT treated groups when compared to control group. The tumor regression was significant in both the LDFRT group (p     

A Feasibility Study of Parametric Response Map Analysis of Diffusion-Weighted Magnetic Resonance Imaging Scans of Head and Neck Cancer Patients for Providing Early Detection of Therapeutic Efficacy

The parametric response map (PRM) was evaluated as an early surrogate biomarker for monitoring treatment-induced tissue alterations in patients with head and neck squamous cell carcinoma (HNSCC). Diffusion-weighted magnetic resonance imaging (DW-MRI) was performed on 15 patients with HNSCC at baseline and 3 weeks after treatment initiation of a nonsurgical organ preservation therapy (NSOPT) using concurrent radiation and chemotherapy. PRM was applied on serial apparent diffusion coefficient (ADC) maps that were spatially aligned using a deformable image registration algorithm to measure the tumor volume exhibiting significant changes in ADC (PRM_ADC). Pretherapy and midtherapy ADC maps, quantified from the DWIs, were analyzed by monitoring the percent change in whole-tumor mean ADC and the PRM metric. The prognostic values of percentage change in tumor volume and mean ADC and PRM_ADC as a treatment response biomarker were assessed by correlating with tumor control at 6 months. Pixel-wise differences as part of PRM_ADC analysis revealed regions where water mobility increased. Analysis of the tumor ADC histograms also showed increases in mean ADC as early as 3 weeks into therapy in patients with a favorable outcome. Nevertheless, the percentage change in mean ADC was found to not correlate with tumor control at 6 months. In contrast, significant differences in PRM_ADC and percentage change in tumor volume were observed between patients with pathologically different outcomes. Observations from this study have found that diffusion MRI, when assessed by PRM_ADC, has the potential to provide both prognostic and spatial information during NSOPT of head and neck cancer.     

Use of tumor markers in the management of head and neck cancer

Serologic tumor markers have been evaluated in the diagnosis, management and follow-up of patients with head and neck cancer. However, to the authors' knowledge no tumor marker has yet been shown to be useful for monitoring the response to chemotherapy in this type of disease, in particular for undifferentiated tumors. The pretreatment levels of CEA, TPA, SCC and ferritin were evaluated in 98 patients with advanced head and neck cancer. Of this group 64 patients were studied sequentially every month during planned chemotherapy and three weeks after treatment using standard commercial kits. The results showed the following sensitivity values: TPA 50%, CEA 36%, SCC 34% and ferritin 19%. The incidence and magnitude of the marker elevations were correlated with the extent of disease. In patients with squamous cell cancer SCC and CEA were elevated (by 68% and 54%, respectively) in tumors with good differentiation (G1), but only by 13% (both markers) in tumors classified as poorly differentiated (G3). CEA, SCC and ferritin serum levels were not correlated with response to chemotherapy, while TPA values correlated with the clinical response to treatment in 100% of patients with undifferentiated cancer and in 75% of those with squamous cell cancer. Our data indicate that in patients with head and neck cancer TPA appears to be a sensitive marker, followed in decreasing order of sensitivity by CEA, SCC and ferritin. However, SCC and CEA seem to be the most suitable markers for squamous cell cancer and in particular for more differentiated tumors (G1). Finally, TPA has proved to be a useful marker for monitoring the response to chemotherapy in patients with head and neck cancer, in particular for undifferentiated tumors.     

Concomitant expression of E. coli cytosine deaminase and uracil phosphoribosyltransferase improves the cytotoxicity of 5-fluorocytosine

The prodrug activation system formed by the E. coli codA gene encoding cytosine deaminase (CD) and 5-fluorocytosine (5-FC) developed for selective cancer chemotherapy suffers from a sensitivity limitation in many tumour cells. In an attempt to improve the CD/5-FC suicide association, we combined the E. coli upp gene encoding uracil phosphoribosyltransferase (UPRT) with codA gene to create the situation prevailing in E. coli, a bacterium very efficient in metabolising 5-FC. The constitutive expression of the two genes cloned on an E. coli-animal cell shuttle plasmid either in a linked or in a fused configuration was evaluated in E. coli strains selected and engineered to mimic the 5-FC metabolism encountered in mammalian cells. The simultaneous expression of codA and upp genes generated a cooperative effect resulting in a dramatic increase in 5-FC sensitivity of cells compared to the expression of codA alone. Furthermore, it was shown that the association of UPRT with CD facilitated the uptake of 5-FC, in the situation where the drug penetrates cells by passive diffusion as in mammalian cells, by directly channeling 5-fluorouracil, the product of CD, to 5-fluoroUMP, the product of UPRT.     

Levamisole and 5-fluorouracil therapy for resected colon cancer: a new indication.

OBJECTIVE: To evaluate the benefits and risks of postoperative treatment with levamisole plus 5-fluorouracil (5-FU) in patients with colon cancer. DESIGN: Computerized searches of MEDLINE and CANCERLIT were performed, and the reference list of each retrieved article was checked. Only randomized trials of therapy with levamisole alone or combined with 5-FU for colon cancer without distant metastases were included. The studies were then evaluated with the use of four criteria. RESULTS: We reviewed six randomized trials, of which three satisfied our criteria. Two studies demonstrated a significant improvement in the survival rate with levamisole plus 5-FU among patients with colon cancer and pathologically confirmed metastases to adjacent lymph nodes (Dukes'' stage C). A subgroup analysis in another study demonstrated a similar benefit. The toxic effects of the drugs were generally mild. The three other studies showed no difference in survival rates between the treatment groups; however, the samples were too small to detect a clinically or statistically important difference. CONCLUSIONS: Because many patients with colon cancer will suffer a relapse we recommend that they be offered the opportunity to participate in clinical trials of adjuvant therapy. For those with stage C disease not entering a clinical trial levamisole plus 5-FU is appropriate adjuvant therapy.     

Immune restoration in head and neck cancer patients after in vivo COX-2 inhibition

Purpose To determine the immunomodulatory effects of in vivo COX-2 inhibition on leukocyte infiltration and function in patients with head and neck cancer. Experimental design Patients with squamous cell carcinoma of the head and neck preoperatively received a specific COX-2 inhibitor (rofecoxib, 25 mg daily) orally for 3 weeks. Serum and tumor specimens were collected at the start of COX-2 inhibition (day 0) and again on the day of surgery (day 21). Adhesion to peripheral blood monocytes to ICAM-1 was examined. Percentages of tumor-infiltrating monocytes (CD68, CCR5) and lymphocytes (CCR5, CD4, CD8 and CD25) were determined by immunohistochemistry. Results Monocytes obtained from untreated cancer patients showed lower binding to ICAM-1 compared to monocytes of healthy donors but significantly regained adhesion affinity following incubation in sera of healthy donors. Conversely, sera of cancer patients inhibited adhesion of healthy donors’ monocytes. Tumor monocyte adhesion to ICAM-1 was increased (P < 0.001) after 21 days of COX-2 inhibition, and concomitant increases in tumor infiltrating monocytes (CD68+), lymphocytes (CD68− CCR5+, CD4+ and CD8+) and activated (CD25+) T cells were observed. Conclusions Short-term administration of a COX2 inhibitor restored monocyte binding to ICAM-1 and increased infiltration into the tumor of monocytes and Th1 and CD25+ activated lymphocytes. Thus, in vivo inhibition of the COX-2 pathway may be useful in potentiating specific active immunotherapy of cancer.     

First reported case of concurrent sonidegib and radiotherapy for recurrent,advanced basal cell carcinoma

Basal cell carcinoma (BCC ) is the most common human malignancy. Systemic therapy with a sonic hedgehog (SHH) pathway inhibitor plays an important role in the treatment of advanced BCC . Literature on concurrent use of radiation therapy (RT ) with SHH inhibitors has been minimal and has solely been focused on vismodegib. We present a case report of a patient with recurrent basal cell carcinoma involving the high-risk area of the face, who was denied surgery due to comorbidities and difficulty in obtaining complete tumor removal without cosmetic or functional impairment. The patient received combined treatment of fractionated radiation with concurrent sonidegib and had complete clinical response with no significant toxicities. This is the first reported case on the use of concurrent RT with sonidegib for management of recurrent basal cell carcinoma of the head and neck.     

Nitric oxide synthase inhibition enhances the antitumor effect of radiation in the treatment of squamous carcinoma xenografts

This study tests whether the nitric oxide synthase (NOS) inhibitor, N(G)-nitro-L-arginine (L-NNA), combines favorably with ionizing radiation (IR) in controlling squamous carcinoma tumor growth. Animals bearing FaDu and A431 xenografts were treated with L-NNA in the drinking water. IR exposure was 10 Gy for tumor growth and survival studies and 4 Gy for ex vivo clonogenic assays. Cryosections were examined immunohistochemically for markers of apoptosis and hypoxia. Blood flow was assayed by fluorescent microscopy of tissue cryosections after i.v. injection of fluorospheres. Orally administered L-NNA for 24 hrs reduces tumor blood flow by 80% (p<0.01). Within 24 hrs L-NNA treatment stopped tumor growth for at least 10 days before tumor growth again ensued. The growth arrest was in part due to increased cell killing since a combination of L-NNA and a single 4 Gy IR caused 82% tumor cell killing measured by an ex vivo clonogenic assay compared to 49% by L-NNA or 29% by IR alone. A Kaplan-Meyer analysis of animal survival revealed a distinct survival advantage for the combined treatment. Combining L-NNA and IR was also found to be at least as effective as a single i.p. dose of cisplatin plus IR. In contrast to the in vivo studies, exposure of cells to L-NNA in vitro was without effect on clonogenicity with or without IR. Western and immunochemical analysis of expression of a number of proteins involved in NO signaling indicated that L-NNA treatment enhanced arginase-2 expression and that this may represent vasculature remodeling and escape from NOS inhibition. For tumors such as head and neck squamous carcinomas that show only modest responses to inhibitors of specific angiogenic pathways, targeting NO-dependent pro-survival and angiogenic mechanisms in both tumor and supporting stromal cells may present a potential new strategy for tumor control.     

Simultaneous Integrated Boost Radiotherapy in Unresectable Stage IV (M0) Head and Neck Squamous Cell Cancer Patients: Daily Clinical Practice

AimTo evaluate clinical outcome in locally-advanced stage IV (M0) head and neck cancer patients treated using intensity-modulated radiotherapy (IMRT) with simultaneous integrated boost (SIB) in daily clinical practice.BackgroundDespite SIB-IMRT has been reported as a feasible and effective advanced head and neck cancer treatment, there are few data about its concurrent use with systemic therapies.Material and MethodsWe reviewed 41 staged IV (M0) head and neck cancer patients treated in two radiotherapy units in the city of Messina (Italy) during the last six years, using intensity modulated techniques-SIB. 22/41 patients had concomitant chemotherapy or cetuximab. Acute and late toxicities, objective response (OR) rate, local control (LC) and overall survival (OS) have been evaluated.Results37/41 patients received the planned doses of radiotherapy, 2 patients died during the therapy. The major acute regional toxicities were skin reaction and mucositis. A case of mandibular osteoradionecrosis was recorded. At completion of treatment, OR was evaluated in 38 patients: 32/38 patients (84.2%) had complete (55.3%) and partial (28.9%) response. The 1- and 5-year LC rates were 73.4% and 69.73%, respectively. The 1-, 3-, and 5-year OS rates were 85.93%, 51.49% and 44.14%, respectively. No statistically significant differences in outcomes have been observed in patients treated with radiotherapy alone vs. irradiation concomitant to chemo/biotherapy. The median OS was 45 months.ConclusionSIB-IMRT is safeand can be used with concomitant chemotherapy/biotherapy in real-life daily clinical practice. SIB-IMRT alone is a valid alternative in patients unfit for systemic therapies.     

CD98 marks a subpopulation of head and neck squamous cell carcinoma cells with stem cell properties

Patients with advanced head and neck squamous cell carcinomas (HNSCCs) are often treated with concomitant chemotherapy and radiotherapy, but only 50% is cured. A possible explanation for treatment failure is therapy resistance of the cancer stem cells (CSCs). The application of compounds specifically targeting these CSCs, in addition to routinely used therapeutics, would likely improve clinical outcome. We demonstrate that the previously described monoclonal antibody K984 recognizes the CD98 cell surface protein, which is specifically expressed by cells forming the squamous basal cell layer, the region where the squamous stem cells reside. Moreover, CD98 is highly resistant to the proteolytic enzymes required for CSC enrichment procedures. We show that CD98^high cells, in contrast to CD98^low cells, are able to generate tumors in immunodeficient mice, indicating that CD98^high cells have stem cell characteristics. Furthermore, the CD98^high subpopulation expresses high levels of cell cycle control and DNA repair genes, while the CD98^low fraction shows expression patterns that represent the more differentiated cells forming the bulk of the tumor. CD98 is a promising CSC enrichment marker in HNSCC. Our data support the CSC concept in head and neck cancer and the potential relevance of these cells for treatment outcome.     

Antithyroid cancer effects of human neural stem cells expressing therapeutic genes on anaplastic thyroid cancer cells

Stem cells that express therapeutic proteins have been identified to have an anticancer effects on various types of cancer. In the present study study, human neural stem cells (hNSCs) that were genetically engineered to express cytosine deaminase (CD) and human interferon-β (IFN-β) were used for anaplastic thyroid cancer (ATC) treatment owing to their tumor-tropic properties and therapeutic effects. CD is an enzyme that converts 5-fluorocytosine (5-FC), a prodrug, to 5-fluorouracil (5-FU) which is a medication to suppress tumor growth through DNA synthesis inhibition. Also, IFN-β suppresses tumor growth by the induction of apoptotic process. In water soluble tetrazolium salt (WST) assay, SNU-80 cells which are human female ATC cells were cocultured with three cell types including engineered hNSCs such as HB1.F3, HB1.F3.CD, and HB1.F3.CD.IFN-β cells on transwells and treated with 5-FC for 72 hours. Finally, the SNU-80 cell viability was reduced by the coculture with HB1.F3.CD and HB1.F3.CD.IFN-β cells. In dichlorofluorescein diacetate (DCF-DA) and TdT-mediated dUTP nick-end labeling (TUNEL) assays, the production of reactive oxygen species (ROS) and the number of apoptotic cells were increased by HB1.F3.CD and HB1.F3.CD.IFN-β cells in the presence of 5-FC. In Western blot assay, ROS, and apoptosis-related genes were increased in SNU-80 cells when they were cocultured with HB1.F3.CD and HB1.F3.CD.IFN-β cells. In transwell migration assay, hNSCs selectively migrated to SNU-80 cells because hNSCs interacted with chemoattractant factors like SDF-1α, uPAR, and CCR2 secreted by SNU-80 cells. Taken together, engineered hNSCs were revealed to selectively migrate to ATC cells and to inhibit growth as well as to induce apoptosis of ATC cells via ROS production through the actions of transgenes such as CD and IFN-β. Therefore, these engineered hNSCs can be promising candidates for the treatment of metastatic ATC.     

中药组方黄芩汤抑制胃癌细胞增殖的实验研究

目的探讨黄芩汤对胃癌细胞生长增殖及干细胞标志物表达的影响。 方法采用体外优化培养的胃癌细胞株SGC-7901模型,分别加入生理盐水、5-FU、黄岑汤和5-FU+黄芪汤干预,MTT法检测胃癌细胞增殖情况,Real-time PCR检测胃癌干细胞相关表面标志物CD44、EpCAM、CD90的表达情况;并进一步利用胃癌细胞裸鼠荷瘤模型,观察黄岑汤协同5-FU对体内肿瘤生长的抑制效果。细胞增殖曲线多组间数据比较采用重复测量数据方差分析,单时间点多组数据采用单因素方差分析,组间比较采用Tukey法。 结果优化培养的胃癌细胞SGC- 7901呈球形生长,细胞活性染色显示良好的活性状态;MTT结果显示,黄岑汤组（0.44±0.04）能够抑制胃癌细胞的增殖,从第4天起与对照组（0.59±0.02）相比,差异具有统计学意义（F = 39.550,P < 0.01）;黄岑汤联合5-FU组（0.36±0.04）加强5-FU对肿瘤细胞的抑制作用,从第3天起与对照组（0.50±0.01）相比,差异具有统计学意义（F = 10.670,P < 0.01）,与5-FU组（0.42±0.03）对比,差异具有统计学意义（F = 10.670,P < 0.05）;Real-time PCR结果显示黄岑汤联合5-FU可抑制胃癌细胞中肿瘤干细胞相关表面标志物CD44、EpCAM、CD90表达（P < 0.01）;移植瘤生长抑制实验发现黄芪汤组对荷瘤鼠移植瘤的生长具有抑制作用,与对照组相比移植瘤体积减小,差异具有统计学意义（P < 0.01）,黄岑汤联合5-FU组与5-FU组相比对移植瘤抑制效果更明显,差异具有统计学意义（P < 0.01）。 结论黄芪汤能抑制胃癌细胞的生长和增殖,并能协同5-FU产生抗肿瘤作用。