Glioma and temozolomide induced alterations in gut microbiome

The gut microbiome is fundamental in neurogenesis processes. Alterations in microbial constituents promote inflammation and immunosuppression. Recently, in immune-oncology, specific microbial taxa have been described to enhance the effects of therapeutic modalities. However, the effects of microbial dysbiosis on glioma are still unknown. The aim of this study was to explore the effects of glioma development and Temozolomide (TMZ) on fecal microbiome in mice and humans. C57BL/6 mice were implanted with GL261/Sham and given TMZ/Saline. Fecal samples were collected longitudinally and analyzed by 16S rRNA sequencing. Fecal samples were collected from healthy controls as well as glioma patients at diagnosis, before and after chemoradiation. Compared to healthy controls, mice and glioma patients demonstrated significant differences in beta diversity, Firmicutes/Bacteroides (F/B) ratio, and increase of Verrucomicrobia phylum and Akkermansia genus. These changes were not observed following TMZ in mice. TMZ treatment in the non-tumor bearing mouse-model diminished the F/B ratio, increase Muribaculaceae family and decrease Ruminococcaceae family. Nevertheless, there were no changes in Verrucomicrobia/Akkermansia. Glioma development leads to gut dysbiosis in a mouse-model, which was not observed in the setting of TMZ. These findings seem translational to humans and warrant further study.

Landscape of Genomic Alterations in IDH Wild-Type Glioblastoma Identifies PI3K as a Favorable Prognostic Factor

PURPOSE

IDH wild-type (WT) glioblastoma (GBM) is an aggressive tumor with poor survival despite current therapies. The aim of this study was to characterize its genomic profile and determine whether a particular molecular signature is associated with improved survival outcomes.

PATIENTS AND METHODS

Tumor samples from 232 patients with IDH-WT GBM were sequenced, and the landscape of genomic alterations was fully delineated. Genomics data from The Cancer Genome Atlas (TCGA) cohort were analyzed for confirmation. Association of alterations with survival was evaluated in both univariable and multivariable approaches.

RESULTS

The genomic landscape of IDH-WT GBM revealed a high frequency of CDKN2A/B loss, TERT promoter mutations, PTEN loss, EGFR alteration, and TP53 mutations. Novel variants or gene mutations, such as ARID1B and MLL2, were identified. To better understand synergistic effects and facilitate decision making for precision medicine, we identified 11 pairs of gene alterations that tended to co-occur or were mutually exclusive, which were confirmed in the TCGA cohort. Survival analysis showed that genomic alterations in TP53 were associated with worse overall survival (OS). However, alterations in PI3K class I genes were associated with significantly better OS (univariable analysis: P = .002; multivariable analysis: hazard ratio [HR], 0.5785; P = .00162) and longer progression-free survival (univariable analysis: P = .0043; multivariable analysis: HR, 0.6228; P = .00913).

CONCLUSION

Genomic alterations in PI3K class I are a favorable prognostic factor in IDH-WT GBM. This new prognostic biomarker may facilitate risk stratification of patients, assist in clinical trial enrollment, and provide potential therapeutic targets

Additional genetic alterations in BRAF-mutant gliomas correlate with histologic diagnoses

INTRODUCTION

Recently, the term "Diffuse glioma, BRAF V600E-mutant" has been recommended for IDH-wildtype gliomas with BRAF p.V600E mutation and without CDKN2A/B deletion. However, additional alterations in gliomas that coexist with BRAF-mutations are poorly defined.

METHODS

We analyzed next-generation sequencing results in 315 cancer-associated genes for 372 gliomas from our institution (2010 to 2017). In addition, we reviewed IDH-WT gliomas with mutation and copy-number alterations available in cBioPortal, to further characterize BRAF-mutant gliomas.

RESULTS

Seventeen (4.6%) showed BRAF mutations. Tumor types included 8 glioblastomas, 2 epithelioid glioblastomas (E-GBM), 2 pleomorphic xanthoastrocytomas (PXA), 1 anaplastic oligodendroglioma, 1 diffuse astrocytoma, and 3 pilocytic astrocytomas. Fifty-three percent (53%) of cases exhibited BRAF-alterations other than p.V600E. The majority of the tumors were localized in the temporal lobe (52.9%). In addition to BRAF mutations, glioblastomas showed concomitant mutations in TP53 (3/8), CDKN2A/B-loss (6/8), TERT-promoter (6/8), and/or PTEN (5/8). Both E-GBMs and PXAs showed CDKN2A/B-loss and BRAF p.V600E with absence of TERTp, TP53, and PTEN mutations. Similar findings were observed in BRAF-mutant infiltrating gliomas from cBioPortal.

CONCLUSIONS

Knowledge of additional alterations that co-occur with BRAF-mutations in gliomas may improve diagnosis and help identify patients that could benefit from targeted therapies. Furthermore, we provide examples of two patients whose tumors responded to BRAF pathway inhibitors, arguing in favor of these therapies in patients with BRAF-mutant gliomas.

EPID-12. IMPACT OF RACE AND GEOGRAPHIC LOCATION ON IDH MUTATIONS AND GLIOBLASTOMA SURVIVAL

Glioblastoma (GBM) is the most common primary malignant brain tumor of the central nervous system with a 5-year survival of < 5%. Population studies have demonstrated that among all ethnicities, non-Hispanic whites (NHW) have the worst prognosis; however, differences within the oncogenome based on ethnicity have not been assessed. We utilized the Texas Cancer Registry (TCR) for population-based analysis including 4,134 GBM patients between the years of 1995 to 2013 with 75.6% NHW and 16.5% Hispanics. In accordance with previously published findings, within the TCR we detected a 12% relative survival improvement in Hispanics compared to NHW when controlling for known survival mediators including age, resection, chemotherapy, and radiation. In order to assess for oncogenic differences, we utilized a prospectively maintained database of 257 GBM patients within the city of Houston, TX (14.9% Hispanic) and 48 GBM patients from the National Institute of Neurology and Neurosurgery in Mexico City, Mexico (100% Hispanic) to assess for oncogenomic differences attributable to ethnicity. Next generation sequencing of GBM within the Houston cohort, for 315 tumor-related genes, identified no significant differences in genomic alterations owing to ethnicity. However, when we compared the multigenerational, mixed-heritage Hispanics present in the Houston cohort to the Mexico cohort (Sanger sequencing), a significant difference was found in the frequency of IDH1and IDH2mutations (29.8 % Mexico Hispanics, 7.9% Houston Hispanics; p=0.014). In particular, the rate of IDH2mutations is significantly enriched in the Mexico population (19%) when compared to the Houston population (0%) or to previously published rates of IDH2 mutations in GBM (~3%). Ultimately, these findings highlight the need for multiethnic trial enrollment as well as the need for improved testing of IDH2 mutations in patients of distinct ethnicities. Future studies are needed to identify the mechanisms promoting the increased frequency of IDH2 mutations in Mexican Hispanics.

CBMT-40. THE RELATIONSHIP BETWEEN GLIOMA AND THE GUT-BRAIN AXIS

Recent studies demonstrate the potential role of the microbiome in immune-oncology, revealing specific microbial taxa can augment the effects of various therapeutic modalities against tumors. Gut dysbiosis, a disequilibrium in the host’s bacterial ecosystem, can potentially lead to overrepresentation of some bacteria and favor chronic inflammation and immunosuppression. However, the effects of microbial dysbiosis on non-gastrointestinal cancers in particular gliomas are unknown. Here, we explored the effects of glioma and Temozolomide (TMZ) on the fecal microbiome (FM) in mice (n=24) and FM and metabolome in humans (n=40). Aged C57/B6 mice were implanted with Gl261 tumor cells or vehicle and were assigned to one of the following treatment (oral) groups: vehicle, 5mg/kg TMZ or 25mg/kg TMZ beginning 14 days after surgery for 3-weeks following a 5 day on/2 day off treatment. Fecal samples were collected prior to surgery, at treatment initiation and weekly thereafter until sacrifice and sequenced for 16s RNA. Fecal samples were collected from humans with newly diagnosed glioma before resection, chemoradiation, and after chemoradiation (16s RNA, metabolomic, neurotransmitter analysis). In mice, FM beta diversity was significantly altered with glioma (p=0.003) while the alpha diversity remained unchanged. At a genus and family level analysis the relative abundance of Bacteroides (p=0.01) and Bacteroidaceae (p=0.02) was increased. Beta diversity of mice receiving 5mg/kg TMZ changed from baseline (p=0.02). Collectively, this suggests that glioma alters the FM, to what consequence remains to be explored. Alpha (Observed OTUs, p=0.029) and beta diversity (p=0.034) differences in mice correlated with survival (< 25 - >25 days). In humans, norepinephrine and 5-hydroxyindoleacetic acid were significantly lower in glioma patients at diagnosis compared to controls. Our findings demonstrate for the first time the relationship between glioma and the gut-brain axis. Understanding alterations in the FM in glioma patients may allow novel interventions and should be further investigated.

OTHR-06. ANALYSIS OF GENOMIC ALTERATIONS IN 154 BRAIN METASTASES

Brain Metastases (BM) are associated with poor prognosis. Understanding the genomic alterations (GA) that drive tumor metastasis to the brain will increase our ability to identify patients at risk for BM, and provide better opportunities to implement targeted therapies. We performed a retrospective review of genomic alterations in 154 patients with BM from various primary sites (80 Lung, 22 Breast, 16 Melanoma, 5 Kidney, 4 Colorectal, 4 Prostate, and 23 carcinomas from unknown primary (UP). All cases were analyzed by a next generation sequencing assay the detects mutations in the coding region of 327 genes and rearrangements involving 37 genes. The most commonly mutated genes were; TP53, CDKN2A/B, KRAS, MYC, RB1, NF1, PIKC3A, STK11, and PTEN. A comparison of GA in our BM cases with unmatched primary tumors from COSMIC revealed differences in the frequency of mutated genes: TP53 (Lung 85% vs 38%, Breast 63.6% vs 26.0%) CDKN2A/B (Lung 33.7% vs 7%, Melanoma 56.2% vs 18%, Kidney 40% vs 2%, UC 34.7% vs 9%), ERBB2 (Breast 36.3% vs 4%), MYC (Breast 36.36% vs 0.3%), TERT (Melanoma 62.5% vs 25%, Kidney 40% vs 2%), APC (Colon 100% vs 48%), KRAS (Colon 100% vs 31%), PTEN (Prostate 50% vs 7%), TSC1 (Kidney 40% vs 2%), STK11 (UC 26.0% vs 6%). Our results demonstrate a higher frequency of TP53 mutations (p=0.001) in metastatic lung cancer, and a higher frequency of MYC amplification (p=0.01) in metastatic breast cancer, when compared to primary tumors. The present study demonstrates significant differences in the frequency of mutations between primary tumors and BM. Such differences may play an important role in the pathogenesis of BM and may allow for targeted strategies utilizing existing therapies.

Insulin sensitivity at diagnosis of Type 2 diabetes is not associated with subsequent cardiovascular disease (UKPDS 67)

AIMS

Insulin resistance is common in Type 2 diabetes which, in turn, is associated with a markedly increased risk of cardiovascular disease. Whether insulin sensitivity measured after diagnosis of diabetes is associated with incident cardiovascular disease was evaluated in this prospective study.

METHODS

Three thousand five hundred and eighty-two subjects with newly diagnosed diabetes, recruited to the UK Prospective Diabetes Study (UKPDS), free of cardiovascular disease, and with complete information on insulin sensitivity and potential confounders, were followed prospectively to the first occurrence of (i) fatal or non-fatal myocardial infarction, MI (ii) fatal or non-fatal stroke, and (iii) coronary heart disease, CHD (fatal or non-fatal MI, sudden death or ischaemic heart disease). Insulin sensitivity was measured by Homeostatic Model Assessment (HOMA).

RESULTS

Insulin sensitivity as measured by HOMA was not associated with subsequent MI, stroke, or CHD in univariate or multivariate models controlling for age, sex, ethnicity, HbA(1c), body mass index, plasma triglycerides, cholesterol and smoking. The hazard ratio associated with a doubling of insulin sensitivity with fatal or non-fatal MI in a multivariate model was 0.92 (95% confidence interval, CI, 0.80-1.05). These results were not changed by the exclusion of overweight patients randomized to metformin.

DISCUSSION

Estimation of insulin sensitivity provides no additional useful information with respect to the risk of the first occurrence of cardiovascular disease in patients with newly diagnosed Type 2 diabetes. Among patients with Type 2 diabetes, insulin resistance is not a risk factor for cardiovascular disease.

Facial and abdominal hair growth in hirsutism: a computerized evaluation

Methods of objectively assessing the growth rate of hairs in hirsute women have generally required some form of shaving and have focused on studying hairs affecting the face, which has reduced the number of patients willing or able to participate in such studies. A possible solution is to assess the terminal hairs on the lower abdomen (ie, the male escutcheon) because these two body areas are the most frequently affected with excess hair growth in hirsute patients. Nonetheless, it is unclear how the growth characteristics (density, diameter, and growth rate) of the hairs on the abdomen and face differ in these patients. We hypothesize that the growth characteristics of terminal hairs on the abdomen and face are similar and that evaluation of either area may be sufficient in assessing the hair growth rate of these patients. To objectively evaluate hair growth in the face and abdomen in hirsute patients, we developed a computer-aided image analysis system capable of measuring several growth parameters. Twenty hirsute women (12 white and 8 black), aged 31.2 +/- 6.1 years, were studied. Facial and abdominal skin areas were shaved, and 3 to 5 days later the areas were photographed through a calibrated glass plate and 5 terminal hairs were plucked from each area. The daily hair growth rate (assessed by photography and by direct measurement of the plucked hair), the density of hairs (number of hairs per surface area assessed by photography), and hair diameter (of the plucked hairs) were determined. The extent of hirsutism was also measured, albeit subjectively, by a modification of the Ferriman-Gallwey method, with each area given a score of 0 (no terminal hairs seen) to 4 (terminal hairs in a pattern similar to that of a very hirsute man). Facial, abdominal, and total Ferriman-Gallwey scores were 1.3 +/- 0.6, 1.8 +/- 0.9, and 12.5 +/- 5.4, respectively. Our results indicated that facial hairs were distributed in greater density and had a greater diameter than abdominal hairs (15.6 +/- 14.2 hairs/cm(2) vs 5.4 +/- 1.9 hairs/cm(2), and 84.5 +/- 19.5 microm and 66.2 +/- 17.5 microm, respectively, P <.005). Alternatively, the growth rates of facial and abdominal hairs were similar, whether determined photographically (0.36 +/- 0.18 mm/day vs 0.43 +/- 0.19 mm/day, respectively) or from plucked hairs (1.2 +/- +0.2 mm/d vs 1.4 + 0.4 mm/d, respectively). We conclude that although the density and diameter of facial hairs are greater than that of lower abdominal hairs, these areas have very similar growth rates. Hence evaluation of either of the body areas, using an objective method of assessing hair growth, should provide equivalent results.

Repeated freezing and thawing does not generally alter assay results for several commonly studied reproductive hormones

OBJECTIVE

To determine the effect of repeated freezing and thawing, and storage temperature, on the assay results of commonly measured reproductive hormones, and sex hormone-binding globulin (SHBG) in human serum.

DESIGN

Prospective laboratory study.

SETTING

Academic medical center.

PATIENT(S)

Four men and three pregnant women in the third trimester.

INTERVENTION(S)

Pooled serum from men and pregnant females were frozen at either -20 degrees C or -70 degrees C. Aliquots were then subjected to repeat freeze/thaw cycles, from 1 to 10 times, and assays were performed after the final freeze/thaw cycle.

MAIN OUTCOME MEASURE(S)

Assay results for eight hormones (FSH, LH, PRL, androstenedione (A), 17alpha-hydroxyprogesterone, P, insulin, and SHBG, as a function of the number of freeze/thaw cycles and storage temperature.

RESULT(S)

Only SHBG in male serum at -20 degrees C and P in pregnant serum at -70 degrees C showed statistically significant decreases in assay results with repeated freeze/thaw cycles (3.3% and 1.1% per cycle, respectively). All other analytes did not show significant changes as a function of freeze/thaw cycles or storage temperature.

CONCLUSION(S)

There is no consistent or predictable alteration in the results of SHBG, or the glycoprotein and steroid hormones evaluated, as a function of repeated freeze/thaw or the storage temperature of human serum.

Chronic mesenteric ischemia: diagnosis and treatment

Chronic mesenteric ischemia is an uncommon manifestation of atherosclerotic disease. The presentation of chronic mesenteric ischemia is often confusing and the diagnosis is usually not made until late in the course of the disease. Selective angiography is considered the gold standard for establishing the diagnosis of chronic mesenteric ischemia. The treatment options for patients presenting with symptomatic chronic mesenteric ischemia include various surgical approaches to revascularization and catheter-based interventions.

Examination of the chin or lower abdomen only for the prediction of hirsutism

OBJECTIVE

To test the hypothesis that scoring terminal hair growth on only the chin or abdomen can serve as a reliable predictor for hirsutism.

DESIGN

A prospective observational study.

PATIENT(S)

Six hundred and ninety-five consecutive hyperandrogenic women seen between June 1987 and December 1997.

MAIN OUTCOME MEASURE(S)

All hirsutism exams were performed by one examiner. Hirsutism was scored using a modification of the Ferriman-Gallwey (F-G) method. An F-G score of > or = 8 defined hirsutism.

RESULT(S)

Of the 695 women examined 352 (50.1%) had hirsutism scores of 8. Thirty percent (79 of 344) of women who had an F-G score of <8 had previously underwent electrology. If either the chin or lower abdomen hair growth score was > or = 2, the sensitivity was 100% for the prediction of hirsutism, although the specificity was 27%. The positive predictive value (PPV) for hirsutism using a hair score of > or = 2 at either of these sites was 58%.

CONCLUSION(S)

A hair growth score of > or = 2 on the chin or lower abdomen only was found to be a highly sensitive predictor for hirsutism. However, because of its very low PPV, this screening method is virtually useless in populations where the hirsutism frequency is expected to be low, about 5%. However, this screening method for the detection of hirsutism would be useful for the study of high-risk populations with an expected hirsutism prevalence of >20% (e.g., family studies).

Secondary infrageniculate bypass with polytetrafluoroethylene

Autologous saphenous vein is the preferred conduit for infrainguinal reconstructions. Patients requiring secondary infrageniculate bypass represent a challenging surgical problem. Often, patients requiring such surgery have had multiple bypass operations and lack usable saphenous vein. These patients may also be older and have complicated medical problems which may limit their total life expectancy. This report reviews 11 such patients who required secondary bypass procedures for limb salvage. All procedures were performed with thin-walled polytetrafluoroethylene (PTFE). No perioperative complications or deaths occurred. Four patients have subsequently died due to unrelated disease at 8, 12, 13, and 29 months after operation with clinically patent grafts. In the seven surviving patients, four grafts remain patent with a mean (s.d.) patency of 27(21) months. Three grafts occluded at 2, 4 and 20 months after surgery. By life table analysis, cumulative graft patency was therefore 68% at 24 months. It is concluded that in this high-risk population when no saphenous vein is available, PTFE may provide acceptable limb salvage when used in secondary infrageniculate reconstructions.

Effects of lithium and rubidium on immune responses of rats

Rats were treated with LiCl or RbCl in drinking water for 65 days. Spleen cells from both treated groups exhibited significantly greater proliferative responses to lipopolysaccharide (LPS) than those from untreated controls. Responses to concanavalin A (Con A) were not affected. Cytotoxic activities of natural killer (NK) cells from both treated groups were significantly less than those from untreated controls. In vitro, Li augmented responses of spleen cells to LPS, but the same doses of Rb suppressed the responses. Effects on responses to Con A were variable. Both Li and Rb alone had a small mitogenic effect on spleen cells.

Lithium effects on adjunctive alcohol consumption. III: FT-shock as the inducing schedule

Under conditions in which a mild shock (0.5 mA, 200 msec) was delivered, independently of the subject's behavior, every 90 sec (an FT 90-sec shock schedule), subjects receiving chronic lithium chloride in their drinking water (25 mEq/l), showed a rapid acquisition of an adjunctive alcohol consumption, while subjects in the control groups did not. Following termination of the FT-shock condition (extinction), subjects in all groups showed an increase in alcohol consumption, relative to both baseline and adjunctive levels.

Lithium effects on adjunctive alcohol consumption. I: Comparison with adjunctive water consumption

Chronic administration of lithium chloride (20 mEq/l, in drinking water) produced an earlier onset of the adjunctive consumption of both water and alcohol. Terminal consumption levels, however, were unaffected by either lithium or the liquid available for consumption. The rate of increase, once drinking was initiated, was slower for lithium subjects than it was for controls. Under extinction conditions, adjunctive alcohol consumption showed no evidence of decline for either lithium or control subjects. Water consumption by control subjects did decrease considerably as a result of extinction. Subjects receiving lithium, however, maintained their intake of water at terminal adjunctive drinking levels.

Lithium effects on adjunctive alcohol consumption. II: Effects of adding concurrent shock

Rats receiving chronic administration of lithium chloride (20 mEq/l) in their drinking water were tested for adjunctive alcohol (10% v/v) consumption in which temporally scheduled, noncontingent shock delivery was added following the establishment of food delivery-based adjunctive alcohol intake. The addition of shock to the eliciting schedule produced an initial reduction in alcohol consumption (Lithium subjects took longer to reach maximal suppression of drinking than did Controls), with a subsequent return to preshock levels for both groups. The reduction in alcohol consumption seen in control subjects following the discontinuation of food and shock delivery (extinction) was interpreted as suggesting that adding conflict/stress to established drinking conditions may facilitate subsequent extinction of that drinking behavior. Lithium subjects produced an initial suppression of drinking, with alcohol consumption returning to adjunctive levels by the end of the extinction series, suggesting that lithium decreases conflict/stress effects, that it impairs extinction processes, that it increases the reinforcing value of alcohol, or that it produces a combination of the three outcomes.

Lithium effects on adjunctive alcohol consumption in rats

Rats receiving chronic administration of lithium chloride (20 mEq/l) in their drinking water were tested for acquisition of adjunctive alcohol (10% v/v) consumption. Contrary to expectations, subjects receiving lithium acquired the adjunctive drinking more rapidly, and under less optimal conditions, than did control subjects. The high death rate in subjects receiving lithium while undergoing a concurrent alcohol withdrawal suggests that particular caution must be observed when lithium is used in the treatment of alcoholics.

Effects of lithium and rubidium on shock-induced changes in open-field activity

Lithium chloride and rubidium chloride were tested under conditions in which the effects of their chronic administration on aversively-controlled behavior could be assessed. Lithium attenuated shock-induced suppression of open-field activity when that suppression was under the control of mild or moderate stimulus parameters, but had no effect on the suppression produced by the presence of shock itself. Rubidium, on the other hand, increased shock-induced suppression under all conditions. When shock was removed and extinction of the activity suppression was investigated, lithium subjects failed to return to their original baseline activity levels, while subjects receiving rubidium recovered baselines in a manner indistinguishable from that observed in control animals.

Lithium effects on active and passive avoidance behavior in the rat

Lithium chloride reduced the rate of acquisition of a passive-avoidance response and decreased the rats' reaction to the shock delivery. Acquisition of an active-avoidance response was unimpaired by lithium, although lithium-administered rats responded predominantly to the cue stimulus, making significantly fewer precue avoidance responses than did controls. Lithium's efficacy in the treatment of manic disorders may, therefore, be the result of a decrease in the individual's reactivity to low-intensity stimulation.

Effect of parathyroid extract on the development of wound rupture strength

SYNOPSIS IN INTERLINGUA

EFFECTO DE EXTRACTO PARATHYROIDIC SUPER LE DISVELOPPAMENTO DEL FORTIA RUPTURAL IN VULNERES. -Recente studios ha demonstrate que extracto parathyroidic es capace a stimular un factor collagenolytic in osso. Tamen, le responsa de altere tissus conjunctive a extracto parathyroidic ha non essite determinate con respecto a un tal factor. Le presente studio esseva un essayo de demonstrar le effecto de extracto parathyroidic super primari vulneres de pelle in stato de guarition in juvene rattos. Vulnerate animales recipeva un injection de 200 unitates de extracto parathyroidic omne die durante tres dies ante lor sacrificio. Le animales esseva sacrificate 6, 9, e 12 dies post le vulneration. Un analyse statistic del fortia ruptural del vulneres revelava un significative augmento del fortias in vulneres post 9 dies. Le constatationes esseva interpretate como non supportante le hypothese que extracto parathyroidic stimula un factor collagenolytic in le tissu conjunctive de un vulnere in guarition.