Immunotherapeutics for head and neck squamous cell carcinoma stem cells

Cancer stem cell (CSC)-related therapy resistance has become a new obstacle to the successful application of cancer treatment and head and neck squamous cell carcinoma (HNSCC) is no exception to this finding. Head and neck squamous cell carcinoma is highly immune-suppressive, and recently the immune suppression and invasion of HNSCC-CSCs have been characterized. These characteristics have received research and clinical attention because they would enable the stratification of patients into specific cancer subtypes and, consequently, the establishment of new therapeutic approaches with improved efficacy. This review discusses the feasibility of CSC-targeted strategies and their incorporation with nanotechnology to improve the efficacy of cancer immunotherapy.

Predicting Outcome in Subarachnoid Hemorrhage (SAH) Utilizing the Full Outline of UnResponsiveness (FOUR) Score

BACKGROUND

Existing scoring systems for aneurysmal subarachnoid hemorrhage (SAH) patients fail to accurately predict patient outcome. Our goal was to prospectively study the Full Outline of UnResponsiveness (FOUR) score as applied to newly admitted aneurysmal SAH patients.

METHODS

All adult patients presenting to Health Sciences Center in Winnipeg from January 2013 to July 2015 (2.5 year period) with aneurysmal SAH were prospectively enrolled in this study. All patients were followed up to 6 months. FOUR score was calculated upon admission, with repeat calculation at 7 and 14 days. The primary outcomes were: mortality, as well as dichotomized 1- and 6-month Glasgow Outcome Scale (GOS) and modified Rankin Scale (mRS) values.

RESULTS

Sixty-four patients were included, with a mean age of 54.2 years (range 26-85 years). The mean FOUR score upon admission pre- and post-external ventricular drain (EVD) was 10.3 (range 0-16) and 11.1 (range 3-16), respectively. There was a statistically significant association between pre-EVD FOUR score (total, eye, respiratory and motor sub-scores) with mortality, 1-month GOS, and 6-month GOS/mRS (p < 0.05 in all). The day 7 total, eye, respiratory, and motor FOUR scores were associated with mortality, 1-month GOS/mRS, and 6-month GOS/mRS (p < 0.05 in all). The day 14 total, eye, respiratory, and motor FOUR scores were associated with 6-month GOS (p < 0.05 in all). The day 7 cumulative FOUR score was associated with the development of clinical vasospasm (p < 0.05).

CONCLUSIONS

The FOUR score at admission and day 7 post-SAH is associated with mortality, 1-month GOS/mRS, and 6-month GOS/mRS. The FOUR score at day 14 post-SAH is associated with 6-month GOS. The brainstem sub-score was not associated with 1- or 6-month primary outcomes.

HPV vaccination of immunocompromised hosts

It is well-established that immunocompromised people are at increased risk of HPV-related disease compared with those who are immunocompetent. Prophylactic HPV sub-unit vaccines are safe and immunogenic in immunocompromised people and it is strongly recommended that vaccination occur according to national guidelines. When delivered to immunocompromised populations, HPV vaccines should be given as a 3-dose regimen.

Feasibility and acceptance of cervicovaginal self-sampling within the German National Cohort (Pretest 2)

Background and objectives

Within the German National Cohort (GNC) 100,000 adult women in Germany will be comprehensively interviewed and examined. While women’s health is addressed in the basic interview, direct detection of cervicovaginal microbial colonisation or infection is not part of the examination protocol. In a pilot project the feasibility of female study participants of the GNC collecting a cervicovaginal lavage at home without having to involve a gynecologist or other medical personnel was thus investigated. The ability of the procedure to detect vaginal microbes and conditions including human papillomavirus (HPV), Chlamydia trachomatis and bacterial vaginosis (BV) were also explored.

Methods

This cross-sectional study was conducted in two study centers (Hamburg and Hanover) of the GNC during Pretest 2 in 2012 as an add-on module to the main program of the National Cohort. Participants were randomly selected through the population registration office. After providing written informed consent at the study center, participants self-collected a cervicovaginal lavage (Delphi Screener™) at home following written instructions. Participants mailed samples and acceptability questionnaires to the laboratory and the study center, respectively. Acceptability of self-sampling was categorized as consent, partial consent and rejection. The samples were analyzed by multiplex HPV genotyping for the presence of 27 mucosal HPV subtypes. To detect other pathogens “Sexually Transmitted Infection Profiling” (STIP) was used, a novel multiplex polymerase chain reaction (PCR) for various vaginally occurring pathogens/conditions coupled with subsequent bead-based Luminex^® hybridization. Human beta-globin and DNA polymerase alpha (PolA) sequences were used as positive controls for the detection of human DNA during HPV detection and STIP, respectively.

Results

The participation based on the proportion of all women in Pretest 2 who could take part in the add-on Pretest 2 was 67.3 % (109 out of 162). The age of participants ranged from 20 to 69 years. The self-reported median duration of the collection of the lavage was 5 min. Analysis of the questionnaires (n = 108) revealed that the self-sampling of a cervicovaginal lavage was acceptable to 98 % of women (106 out of 108), and considered to be easy by 89 % (96 out of 108) as well as user-friendly by 96 % of the women (104 out of 108). Human beta-globin and PolA as markers for human DNA and sample quality were detected in all samples analyzed while HPV as a marker for pathogen detectability was identified in 18 out of 109 samples. Of the 107 samples tested with STIP as a second marker for pathogen detectability, 5 samples were excluded from statistical analyses on bacterial colonization because of signs in the laboratory results of the use of antibiotics. For the computation of the possible occurrence of bacterial vaginosis and candidiasis 7 and 8 samples, respectively, were excluded because of low signal intensities resulting in an evaluation of 95 or 94 samples, respectively. Ureaplasma parvum was detected in 22 out of 102 samples, BV in 14 out of 95 samples and candidiasis in 13 out of 94 samples. Chlamydia trachomatis was not detected in any sample.

Conclusion

The feasibility study on cervicovaginal self-sampling indicates that this form of biosampling was very well accepted within the framework of the GNC and feasible in terms of pathogen detection. Its further application in the GNC would allow investigation of transience and persistence, or long-term effects of vaginal (co)infections and colonization.

Immunohistochemical Investigation of Metastasis-Related Chemokines in Deep-Infiltrating Endometriosis and Compromised Pelvic Sentinel Lymph Nodes

Endometriosis is a prevalent benign disease, despite sharing several similarities with malignancies, such as the possibility of lymphatic spread. In malignancies, chemokines play a sovereign role in the process of metastasis. Metastasis-related chemokine axes have not yet been assessed in deep-infiltrating endometriosis (DIE), and this investigation was the aim of our study. The expression of these chemokines was investigated by immunohistochemistry in rectovaginal DIE lesions and in matched pelvic sentinel lymph nodes (PSLNs) of patients with endometriosis (n = 27), and their expression in the eutopic endometrium (EE) of endometriosis-free women (n = 20) was used as controls. Their staining pattern in rectovaginal DIE, in endometriotic lesions affecting the PSLN as well as in the EE of patients without endometriosis was characterized for the first time. Overall, these chemokines were highly expressed in DIE and endometriosis in PSLN. Chemokines might be involved in the spread of endometriosis and should be further investigated.

Addition of MCP-1 and MIP-3β to the IL-8 appraisal in peritoneal fluid enhances the probability of identifying women with endometriosis

Chemokines have been associated with endometriosis. Our study was aimed at evaluating the levels of six chemokines--CXCL8 (IL-8), CXCL12 (SDF-1), CCL2 (MCP-1), CCL5 (RANTES), CCL19 (MIP-3β), and CCL21 (6-Ckine)--in the peritoneal fluid (PF) of patients with and controls without endometriosis by multiplexed cytokine assay. In this retrospective case-control study conducted at the Charité University Hospital, patients (n = 36) and controls (n = 27) were enrolled. The patients were separated into groups according to stage of the disease: I-II (n = 21), III-IV (n = 1 5), and according to clinical findings: peritoneal endometriosis (PE; n = 7), deep-infiltrating endometriosis (DIE) affecting the retrocervical area (n = 13) or the bowel/rectovaginal site (n = 14). The subjects were also separated according to the cycle phase: follicular (n = 14) or luteal (n = 8) and the previous use (n = 25) or not (n = 38) of hormones. PF was collected from all subjects (n = 63) consecutively during laparoscopy. The concentration of chemokines in the PF was assessed using Luminex(®) x-MAP(®) technology. Sensitivity and specificity were calculated. A model of multiple logistic regressions estimated the odds of endometriosis for each combination of the chemokines detected. We observed significantly higher concentrations of IL-8 (p < 0.001), MCP-1 (p = 0.014), and MIP-3β (p = 0.022) in the PF of women with endometriosis than in the controls. A joint evaluation revealed that elevated levels of the three chemokines had a positive endometriosis prediction value of 89.1%. The combined assessment of MCP-1, MIP-3β, and IL-8 concentration in PF improved the likelihood of identifying patients with endometriosis. Future studies should investigate this panel in peripheral blood samples.

[Cancer stem cell phenotypes and miRNA: therapeutic targets in head and neck squamous cell carcinoma]

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. HNSCC is caused by persistent high-risk human papillomavirus (HR-HPV) infection or excessive consumption of alcohol or tobacco. The persistently low survival rates result from local recurrences and metastases, which are probably caused by so-called tumor stem cells (TSCs). The epithelial-mesenchymal transition (EMT) or transformation is a key event in metastasis initiation and is being increasingly associated with TSCs.

OBJECTIVES

This review describes new therapeutic targets in HNSCC, focusing on the TSC hypothesis and EMT regulation.

MATERIALS AND METHODS, RESULTS

TSCs and EMT are regulated directly and indirectly via transcription factors and microRNAs (miRNAs). These miRNAs regulate multiple cellular processes and may serve as new therapeutic targets, whose modulation could increase the effectiveness of HNSCC treatments. Post-transcriptionally, miRNAs regulate transcription factors associated with EMT (ZEB1/2, EZH2, Bmi-1), tumor suppressors (p53), TSC markers (ALDH, CD44, EpCAM, p63) and both epithelial (E-cadherin) and mesenchymal markers (vimentin).

CONCLUSION

Alterations in HNSSC TSC miRNA expression before and after chemotherapy could potentially serve as a therapeutic control. In the long term, knowledge of a patient's individual protein expression pattern may permit application of specific chemotherapy. Such individualized therapy might prohibit the development of metastases and potentially unresectable recurrences with a high resistance to radiation and chemotherapy, thus improving the prognosis in HNSCC patients.

Ketamine for medically refractory status epilepticus after elective aneurysm clipping

BACKGROUND

Medically refractory status epilepticus, without an identifiable cause, post elective aneurysm clipping is a rare event.

OBJECTIVE

To describe the two cases of refractory status epilepticus post elective aneurysm clipping, without an identifiable cause, and discuss the potential role for early consideration of ketamine.

METHODS

Retrospectively reviewed two patients at our institution who developed refractory status epilepticus post elective aneurysm clipping, without a defined cause.

RESULTS

Two patients who underwent elective aneurysm clipping developed medically refractory status epilepticus post-craniotomy. No structural, vascular, infectious, or metabolic cause was identified. Seizure control failed with multiple medications and intravenous sedatives over the period of weeks in both. Ketamine was instituted at 20 and 40 mg/kg/min in these patients. Within hours of starting ketamine, burst suppression was obtained in both. Medications were all tapered over the next month, and both the patients recovered to be cognitively normal, with mild residual morbidity secondary to critical care polyneuropathy.

CONCLUSIONS

Refractory status epilepticus, in the absence of an identifiable etiology, in elective aneurysm clipping is a rare event. Consideration should be given for the early use of ketamine in refractory status epilepticus.

[Role of miRNA in malignoma of the head and neck]

Despite optimized therapeutic strategies, the long-term survival of head and neck squamous cell carcinomas (HNSCC) has improved in recent years only slightly. Most studies on the tumor cell genome focus on protein-coding genes (exons). Data on changes within the non-coding sequences (introns) are limited. miRNAs (microRNA, miR) are small non-coding single-stranded RNAs that control gene expression at the posttranscriptional level by interacting with the mRNA. miRNA functions include many biological processes and control up to 50 % of human genes. They can have oncogenic or tumor suppressive functions. Altered expression patterns of miRNAs are involved in carcinogenesis and tumor progression even in HNSCC, or those processes (increased resistance to radiation or chemotherapy) that could be responsible for the poor long-term prognosis by forming metastases and inoperable local recurrences. Therefore, we here present miRNA groups, which are involved in these processes and may serve as new potential therapeutic treatment targets. miRNAs may also serve as biomarkers for early diagnosis, evaluation and monitoring of treatment and tumor recurrence. Alterations in miRNA expression before and after chemotherapy are therefore of high interest. In the long run, this knowledge could lead to more effective therapies with improved therapeutic outcome of HNSCC.

Estimating the long-term effects of HPV vaccination in Germany

In Germany, vaccination against the most oncogenic HPV types 16/18 is recommended by the Standing Committee on Vaccination (STIKO) for 12-17 year old girls since March 2007. We developed a dynamic mathematical model for the natural history and transmission of HPV infections to estimate the impact of vaccination on incidence and mortality of cervical cancer and its pre-stages, and on anogenital warts. We focused on an extensive model calibration to epidemiologic data for all stages of the natural history model as well as on a detailed implementation of cervical cancer screening modalities in Germany. Our model predicts first a substantial reduction of cervical cancer incidence and mortality over the next 30 years, which is mainly attributable to an increase in screening participation in the 1990s and not to HPV vaccination, followed by a further reduction attributable to vaccination. Over the next 100 years, HPV vaccination will prevent approximately 37% of cervical cancer cases even if vaccination coverage is only 50% (as currently observed in Germany). Consideration of cross-protection results in a further reduction of approximately 7% of all cervical cancer cases for the bivalent and about 5% for the quadrivalent vaccine in our model. Vaccination of boys was only reasonable if moderate to high vaccination coverage in girls was not achieved. Strategies should be implemented in Germany to increase HPV vaccination coverage among girls thereby making better use of the demonstrated benefits of the vaccine.

[Biology and relevance of stem cells in squamous head and neck cancer: latest insights and review of literature]

The initiation, growth, recurrence and metastasis of head and neck squamous cell carcinomas (HNSCC) and other cancers have recently been related to the presence of cancer stem cells (CSC). Cancer stem cells have some characteristics in common with tissue stem cells like unlimited self renewal and the expression of stem cell factors. CSC express specific markers that vary considerably depending on tumor type or tissue of origin--the discovery of an universal marker has not yet been made. Compared to the bulk tumor mass, CSC are less sensitive to chemo- and radiotherapy and also have a lower immunogenicity. Another concept that explains the seeding of metastases is the epithelial-mesenchymal transition of CSC. CSC-targeted therapies may change the prognosis of patients with HNSCC in the future. Recent knowledge on the role of CSC in HNSCC is reviewed, and known CSC markers as well as possible therapeutic targets are described.

[Nobel price for vaccination against cervical cancer: current data and guidelines]

Harald zur Hausen received the Nobel price for Medicine in 2008 for his seminal research on human papilloma viruses and their association with anogenital diseases. On the basis of his work highly effective prophylactic vaccines have been developed. Clinical studies have shown nearly 100% seroconversion and an excellent safety profile as well as greater than 96% efficacy against HPV infection and premalignant dysplasia, induced by HPV types covered by the vaccine. Due to the convincing data of phase II and III clinical trials the introduction of HPV vaccination was recommended by health authorities and scientific committees in Germany. The development and availability of guidelines and evidence-based recommendations should support the introduction of the vaccine and widespread vaccination.

A fluorescence resonance energy transfer-based approach for investigating late endosome-lysosome retrograde fusion events

Traditionally, lysosomes have been considered to be a terminal endocytic compartment. Recent studies suggest that lysosomes are quite dynamic, being able to fuse with other late endocytic compartments as well as with the plasma membrane. Here we describe a quantitative fluorescence energy transfer (FRET)-based method for assessing rates of retrograde fusion between terminal lysosomes and late endosomes in living cells. Late endosomes were specifically labeled with 800-nm latex beads that were conjugated with streptavidin and Alexa Fluor 555 (FRET donor). Terminal lysosomes were specifically labeled with 10,000-MW dextran polymers conjugated with biotin and Alexa Fluor 647 (FRET acceptor). Following late endosome-lysosome fusion, the strong binding affinity between streptavidin and biotin brought the donor and acceptor fluorophore molecules into close proximity, thereby facilitating the appearance of a FRET emission signal. Because apparent size restrictions in the endocytic pathway do not permit endocytosed latex beads from reaching terminal lysosomes in an anterograde fashion, the appearance of the FRET signal is consistent with retrograde transport of lysosomal cargo back to late endosomes. We assessed the efficiency of this transport step in fibroblasts affected by different lysosome storage disorders-Niemann-Pick type C, mucolipidosis type IV, and Sandhoff's disease, all of which have a similar lysosomal lipid accumulation phenotype. We report here, for the first time, that these disorders can be distinguished by their rate of transfer of lysosome cargos to late endosomes, and we discuss the implications of these findings for developing new therapeutic strategies.

Estrogen and progestogen receptor positive endometriotic lesions and disseminated cells in pelvic sentinel lymph nodes of patients with deep infiltrating rectovaginal endometriosis: a pilot study

BACKGROUND

Deep infiltrating endometriosis (DIE) shows similarities to malignant diseases. A recent study involving DIE patients found endometriosis in mesorectal lymph nodes (LNs) after segmental bowel resection. However, it is unclear whether this observation is a local phenomenon or a sign of systemic disease. Therefore, we conducted a prospective study to investigate the occurrence of endometriosis in pelvic sentinel lymph nodes (SLNs) in patients with DIE.

METHODS

Fourteen patients underwent primary surgery for symptomatic DIE. Combined vaginal laparoscopic-assisted resection of the rectovaginal septum was performed. Dye was injected into the visible/palpable nodule. SLNs were removed from the iliac region. In order to identify endometriotic cells, immunohistochemical analysis of estrogen and progestogen receptors, CD10 and cytokeratin was performed.

RESULTS

In 12 out of 14 patients with DIE, SLNs were detected. The localization of the SLN followed the typical LN spread of the upper vagina. In three patients, we could detect typical endometriotic lesions in the LNs. Ten out of 12 (83.3%) SLNs showed disseminated estrogen and/or progestogen positive cells.

CONCLUSIONS

By using immunohistochemistry, we could demonstrate endometriotic lesions and endometriotic-like cells in pelvic SLNs of patients with DIE suggesting the potential for lymphatic spread of the disease.

Humorale und zelluläre Immunantwort im Rahmen der HPV-Impfung

Human papillomaviruses (HPV) infect skin or mucosal epithelia causing warts and dysplasia. Infections with certain high-risk HPV types in the anogenital tract can lead to malignant transformation. Cervical cancer is the second most common malignant disease in young women responsible for 275000 deaths annually worldwide. More than 50% of sexually active people acquire HPV infections over their lifetime. Around 80% of infections remain subclinical and are cleared by the immune system. Recently prophylactic vaccines against the two most common high-risk types HPV16 and 18, and additionally low-risk types HPV6 and 11, respectively, have become available. We present an overview concerning recent knowledge on natural and vaccine-induced immunity against HPV infections.

Flt3-ITD mutations can generate leukaemia specific neoepitopes: potential role for immunotherapeutic approaches

Flt3 internal tandem duplications (Flt3-ITD) can be detected in 25 - 30% of acute myeloid leukaemia (AML) and differ in length and sequence. We sequenced patient specific Flt3-ITD mutations in 2 Flt3-ITD positive AML cell lines and 13 Flt3-ITD harbouring AML patients. We addressed the question whether Flt3-ITD mutations can harbour HLA class I specific neoepitopes potentially able to induce a leukaemia and Flt3-ITD specific immune response. Here, we demonstrate that all but 1 Flt3-ITD mutations were unique. Interestingly, the peptide sequence of several Flt3-ITD fusion regions harbour 9 mer neoepitopes that potentially bind to HLA class I molecules in a HLA restricted manner (e.g. A1, A2, B27). The specific binding of Flt3-ITD derived neoepitopes to HLA-A2 is demonstrated. Peptide affinity of HLA-A2-restricted putative neoepitopes can be significantly improved by construction of mimotope candidates. We suggest that Flt3-ITD mutations can form new immunogenic and HLA class I-restricted peptide epitopes.

HPV induced cervical carcinogenesis: molecular basis and vaccine development

Association of infection with papillomavirus and dysplasia of the cervix uteri has been firmly established. There are only few cervical cancers where no HPV DNA is detectable. The mechanism of epithelial cell immortalization by interaction with tumour suppressor genes p53 and pRb by viral oncogenes E6 and E7 is elucidated. Progression of the HPV infected cell to a malignant phenotype involves further modification of host gene expression and/or mutations. The appearance of chromosomal aberrations can lead to mutational inactivation or loss of tumour suppressor genes (TSG), activation and amplification of oncogenes, with importance for the process of carcinogenesis. Oncogene amplification, with exception of few reports, seems not to be a major mechanism in cervical carcinogenesis. In contrast, cytogenetic and loss of heterozygosity (LOH) results from CIN and invasive cancer demonstrate alterations at specific chromosomal regions, pointing at localisation of TSG. Genetic alterations at chromosomes 3p, 6p, 1lq were frequently found early in tumour development Primary invasive carcinoma showed additional allelic losses at chromosome arms 6q, 17p and 18q. Useful biological diagnostic and prognostic markers for high-risk HPV infection and malignant progression may be p16NK4 p27Kip, and NET-I/C4.8. Putative senescence genes relevant for HPV-induced carcinogenesis are localized on chromosomes 2, 4 and 10. Genes for Telomerase suppression are presumably located on chromosomes 3, 4 and 6. Natural immune responses to HPV infection exist Therefore, immune therapy is an attractive possibility for prevention and therapy of HPV infection. To date, vaccine development has reached clinical evaluation. Prophylaxis aims at the induction of virus neutralizing antibodies to capsid proteins. Virus-like particle vaccines are currently tested in clinical trials. Due to the long lag period between infection and clinical manifestation trials will take a long time until conclusive results are obtained. Mandatory expression of viral and perhaps certain cellular genes in infected epithelial and tumour cells offers targets for therapeutic approaches. Since most dysplasia clears spontaneously the viral infection is immunogenic to some extent. However, in some individuals the immune response has to be stimulated by vaccination in order to be effective. Several strategies are being tested in clinical trials and others are in preclinical development The task will be to circumvent immunosuppressive features of the HPV infected cells.

HPV16 L1E7 chimeric virus-like particles induce specific HLA-restricted T cells in humans after in vitro vaccination

Cervical cancer has been shown to be highly associated with human papillomavirus (HPV) infection. The viral oncogenes E6 and E7 are constantly expressed by the tumor cells and are therefore targets for immunotherapy. In the present study we investigated the potential of HPV16 L1E7 chimeric virus-like particles (CVLP) to activate specific cytotoxic T lymphocytes in human blood donors. CVLP were expressed by recombinant baculovirus and purified. Direct incubation of freshly isolated peripheral blood lymphocytes (PBL) with CVLP resulted in induction of proliferation and growth of T cell lines. To enhance antigen presentation we also loaded dendritic cells with CVLP and used them to activate naive T cells. Growing cell lines were mainly CD3 positive (>95%) with a predominant CD4-positive and a minor CD8-positive component. Analysis of Tcell specificity was carried out by an interferon-gamma ELISpot assay. Dendritic cells pseudoinfected with CVLP or pulsed with human leukocyte antigen (HLA)-A*0201-restricted peptide E7(11-20) or with a newly identified HPV16 peptide L1(323-331) were used as stimulator cells. T cells responsive to CVLP were found in the cultures with frequencies of 0.5%-0.7%. Frequencies to peptides were around 0.1%. These T cells had cytolytic activity toward autologous B-lymphoblastic cell lines either pseudoinfected with CVLP or pulsed with HLA-A*0201-restricted peptides. They also lysed the HPV16- and HLA-A*0201-positive cervical cancer cell line CaSki, whereas HLA-A*0201-negative SiHa cells were not lysed. We conclude from our data that CVLP show promise for a therapeutic vaccine in patients with HPV16-positive cervical intraepithelial neoplasia lesions or cervical cancer.

HPV-Infektion und Zervixkarzinom - Epidemiologie, Nachweis und Immunologie

Certain molecularly defined types of human papillomaviruses (HPV) induce, by interaction with additional cofactors, cervical cancer. In comparison to infection with HPV, all risk factors identified to date are less important. In addition to HPV a not yet classified genetic predisposition is important. Identification of HPV in cervical smears is done by detection of viral DNA. PCR based methods have the highest specificity. Currently, first vaccination studies with therapeutic vaccines are performed and phase I/II trials for prophylactic vaccination show promising results.

Comparison of cytokines and CD80 for enhancement of immunogenicity of cervical cancer cells

Tumor cells fail to activate specific cytotoxic T lymphocytes due to lack of costimulatory molecules e.g. CD80 (B7.1). We were able to render cervical carcinoma cells immunogenic by introduction of the CD80 gene into the tumor cells. In order to enhance the efficiency of T cell activation we investigated whether addition of interleukins would augment immunostimulation by CD80. To this end, allogeneic T cells were stimulated with CD80-expressing HeLa cells or CaSki cells in the absence or presence of IL-2, IL-7, IL-12, or combinations thereof. The proliferative response of the T cells was determined. CD80-transduced HeLa or CaSki cells induced a stronger proliferative response in allogeneic T cells than parental or mock transfected control cells. All three interleukins enhanced the proliferative response of allogeneic T cells to CD80-expressing tumor cells. IL-2 or IL-7 had stronger effects in expanding the T cells than IL-12. Combination of IL-2 and IL-7 resulted in best T cell expansion. The proliferating T cells were mainly CD8+ cells with MHC class I restricted and unrestricted cytotoxic activity. Stimulation with CD80 alone or in combination with IL-7 induced mainly cytotoxic T lymphocytes. IL-2, IL-12 or the combination of IL-2 and IL-7 induced natural killer cell-like activity and specific cytolytic activity against parental and CD80-positive tumor cells. Our data suggest that the expression of both CD80 and IL-2 plus IL-7 can enhance the efficacy of tumor vaccines.

Unruptured cerebral aneurysm producing a thunderclap headache

A sudden and severe headache is the most common presentation of an acutely ruptured cerebral aneurysm. A similar headache in the absence of subarachnoid blood has rarely been ascribed to an unruptured cerebral aneurysm, but may result from acute aneurysm expansion and indicate a high risk of future rupture. We present a patient who developed a sudden, severe, "thunderclap" headache, with no associated neurological deficit. Computed tomogram and lumbar cerebral spinal fluid obtained 5.5 hours after headache onset were negative for subarachnoid hemorrhage. The patient underwent cerebral angiography which revealed a posterior communicating artery aneurysm with an associated daughter aneurysm. Craniotomy and clip obliteration of the aneurysm were performed. The aneurysm dome was very thin and there was no evidence of recent or old hemorrhage. A "thunderclap" headache without subarachnoid hemorrhage may be an important harbinger of a cerebral aneurysm with the potential for future rupture. Early recognition and neurovascular imaging of aneurysms presenting in this rare fashion are warranted.

Cervical cancer cells induce apoptosis of cytotoxic T lymphocytes

The goal of immunotherapy is to eliminate tumors by generating tumor-specific cytotoxic T lymphocytes (CTLs) in patients or by adoptively transferring ex vivo-activated CTLs into patients. Clinical trials have shown that tumor-specific CTLs often disappear before tumors are completely eliminated. In this study, the authors show that CTLs specific for cervical tumor cells undergo apoptosis after they are co-cultured with cervical tumor cells. The established cervical tumor cell lines and cervical cancer tissues express CD95 (Fas/Apo-1) ligand. The tumor cell-induced T-cell apoptosis can be blocked by an inhibitory anti-CD95 (APO-1/Fas) antibody, indicating that tumor cells induce apoptosis of CTLs through CD95-CD95 ligand interaction. Addition of interleukin-2 (IL-2) and IL-7 into the culture rescues the CTL from tumor cell-induced apoptosis. The rescued T cells retain their full antitumor cytotoxicity. These data suggest that human cervical tumor cells might actively down-regulate a cellular immune response by inducing apoptosis of specific T cells during immunotherapy. Local use of IL-2 and IL-7 as adjuvants may promote survival of the CTL and, thus, enhance the efficacy of immunotherapy.

Aneurysmal intracerebral hemorrhage: Clinical outcome after emergent surgical treatment

BACKGROUND

Management guidelines and recovery potentials for individuals presenting with poor clinical condition owing to an aneurysmal intracerebral hemorrhage are not well established.

METHODS

We assessed the outcome of a consecutive series of 6 patients with aneurysmal intracerebral hemorrhages presenting with Hunt and Hess clinical grade IV or V selected to undergo emergent hematoma evacuation and aneurysm clip obliteration. Their presenting clinical condition and neuroradiology were assessed, as well as early surgical results and follow-up outcome.

RESULTS

The 2 women and 4 men were 30 to 59 years old. All 6 patients had profound neurological deficits on admission, with Glasgow Coma Scale scores of 4 to 9. Aneurysmal intracerebral hemorrhage diameters measured from 6 to 8 cm and were associated with 5 to 15 mm of midline shift. Surgical intervention was initiated within 3 hours of ictus in 5 patients and within 7 hours in one patient. All 6 patients survived, demonstrated clinical improvement postoperatively, and were transferred to rehabilitation centers 19 to 30 days after presentation. The Glasgow Outcome Scores were 2 to 3 with a minimum follow-up interval of 12 months. Four patients returned home and resumed independent activities of daily living; one required partial supervision. One patient remained in a chronic care facility.

CONCLUSION

An acute management protocol, including aggressive neurosurgical intervention, with craniotomy for hematoma evacuation and aneurysm clip obliteration, can result in good neurological outcome in carefully selected, poor-grade patients with aneurysmal intracerebral hemorrhage.

Near-infrared spectroscopy monitored cerebral venous thrombolysis

BACKGROUND

Cerebral venous thrombosis is a clinical entity which is readily diagnosed with the advent of modern imaging techniques. Anticoagulation is now a standard therapy, but more recent treatment strategies have included endovascular thrombolysis. While the endpoint of this intervention both clinically and radiographically has not been defined, noninvasive monitoring techniques may add further objective measures of treatment response.

CLINICAL PRESENTATION

We present a patient with a four day history of worsening headache and papilledema on exam. Superior sagittal, straight, and bilateral transverse sinus thromboses were identified on computed tomography and angiography.

INTERVENTION

Emergent endovascular thrombolysis by a transvenous approach re-established venous patency and resulted in immediate resolution of the patient's symptoms. Cerebral oximetry by near-infrared spectroscopy was utilized during the procedure, and changes in chromophore concentrations correlated directly with angiographic and clinical resolution of the thrombosis.

CONCLUSION

Near-infrared spectroscopy can provide continuous feedback during thrombolytic therapy in cerebral venous thrombosis and may help define endpoints of such intervention.

Intraoperative loss of auditory function relieved by microvascular decompression of the cochlear nerve

BACKGROUND

Brainstem auditory evoked potentials (BAEP) are useful indicators of auditory function during posterior fossa surgery. Several potential mechanisms of injury may affect the cochlear nerve, and complete loss of BAEP is often associated with postoperative hearing loss. We report two cases of intraoperative auditory loss related to vascular compression upon the cochlear nerve.

METHODS

Intra-operative BAEP were monitored in a consecutive series of over 300 microvascular decompressions (MVD) performed in a recent twelve-month period. In two patients undergoing treatment for trigeminal neuralgia, BAEP waveforms suddenly disappeared completely during closure of the dura.

RESULTS

The cerebello-pontine angle was immediately re-explored and there was no evidence of hemorrhage or cerebellar swelling. The cochlear nerve and brainstem were inspected, and prominent vascular compression was identified in both patients. A cochlear nerve MVD resulted in immediate restoration of BAEP, and both patients recovered without hearing loss.

CONCLUSION

These cases illustrate that vascular compression upon the cochlear nerve may disrupt function, and is reversible with MVD. Awareness of this event and recognition of BAEP changes alert the neurosurgeon to a potential reversible cause of hearing loss during posterior fossa surgery.

Intra-arterial papaverine for the treatment of cerebral vasospasm following aneurysmal subarachnoid hemorrhage

BACKGROUND

Intra-arterial papaverine (IAP) has been described as a treatment for cerebral vasospasm refractory to standard therapy.

METHODS

We report a series of 15 consecutive patients with aneurysmal subarachnoid hemorrhage in which IAP was employed for the treatment of symptomatic vasospasm. All patients exhibited delayed ischemic neurologic deficits, focal cerebral hypoperfusion on stable xenon-enhanced computerized tomography cerebral blood flow studies, and angiographically defined arterial narrowing. Papaverine was infused into 32 arteries on 23 occasions. Six patients required multiple treatments between 1 and 8 days apart. In five instances, IAP was combined with angioplasty.

RESULTS

Angiographically defined vasospasm was at least partially reversed immediately following treatment on 18 of 23 occasions. The associated clinical improvement was major on 6 occasions, and either minor or none on 17. Post-treatment cerebral blood flow was assessed on 13 occasions and showed improvement in previously ischemic areas on six occasions and no improvement on seven. Complications were encountered on four occasions. Systemic hypotension and transient brain-stem depression were seen with vertebral artery infusions; a generalized seizure and paradoxical aggravation of vasospasm resulting in hemispheric infarction occurred with internal carotid artery infusions.

CONCLUSIONS

Intra-arterial papaverine resulted in reversal of arterial narrowing in the majority of cases (78%). However, this angiographic improvement was associated with cerebral blood flow augmentation in only 46% of cases analyzed, and major clinical improvement in 26%.

Ischemic core and penumbra in human stroke

BACKGROUND AND PURPOSE

The ischemic core and penumbra have not been thoroughly characterized after acute cerebral thromboembolic occlusion in humans. Differentiation between areas of potentially viable and irreversibly injured ischemic tissue may facilitate assessment and treatment of stroke patients.

METHODS

Cerebral blood flow (CBF) was measured in 20 patients with acute middle cerebral artery (MCA) occlusion between 60 and 360 minutes after stroke onset, with the stable xenon computerized tomography (CT) technique. Threshold displays were generated at a single level, and the percentages of hemisphere with CBF </=6, </=10, 11 to 20, 21 to 30, and >30 cm3. 100 g-1. min-1 were measured. The corresponding images on 12 available follow-up CT scans were similarly assessed to determine the area of final infarct. Comparisons were analyzed with a paired Student's t test and Pearson's correlation coefficient.

RESULTS

Discrete and confluent areas of CBF </=20 cm3. 100 g-1. min-1 were identified in all patients, ipsilateral to the symptomatic MCA territory. The average area of CBF </=20 cm3. 100 g-1. min-1 within the ipsilateral hemisphere was 66+/-17% compared with 36+/-12% contralaterally (P<0.001). A difference in the extent of low CBF was due primarily to areas with CBF </=10 cm3. 100 g-1. min-1 (48+/-18% versus 16+/-7%, P<0.001). The area of most severe ipsilateral ischemia (</=6 cm3. 100 g-1. min-1) best corresponded to the final area of infarction (37+/-18% versus 40+/-24%; correlation coefficient, 0.866; P<0.01). The acute ischemic core destined to infarction was not surrounded by a widened rim of moderate ischemia because the area with CBF 11 to 20 cm3. 100 g-1. min-1 was similar bilaterally (19+/-4% versus 20+/-7%, P=0.792, thus not significant).

CONCLUSIONS

Our study in acute human stroke involving MCA occlusion indicates that a severely ischemic core (CBF </=6 cm3. 100 g-1. min-1), observed between 1 to 6 hours after stroke onset, corresponds to the cerebral tissue destined to infarction. The ischemic penumbra with flow values between 7 and 20 cm3. 100 g-1. min-1 surrounding the ischemic core is very narrow. Therefore, strategies to improve the outcome of many patients with acute MCA occlusion must either include interventions to reverse the ischemic process within a few minutes of onset or increase the cerebral tolerance of ischemia and thereby prolong the potential therapeutic window.