The GSK3 Signaling Axis Regulates Adaptive Glutamine Metabolism in Lung Squamous Cell Carcinoma

Altered metabolism is a hallmark of cancer growth, forming the conceptual basis for development of metabolic therapies as cancer treatments. We performed in vivo metabolic profiling and molecular analysis of lung squamous cell carcinoma (SCC) to identify metabolic nodes for therapeutic targeting. Lung SCCs adapt to chronic mTOR inhibition and suppression of glycolysis through the GSK3α/β signaling pathway, which upregulates glutaminolysis. Phospho-GSK3α/β protein levels are predictive of response to single-therapy mTOR inhibition while combinatorial treatment with the glutaminase inhibitor CB-839 effectively overcomes therapy resistance. In addition, we identified a conserved metabolic signature in a broad spectrum of hypermetabolic human tumors that may be predictive of patient outcome and response to combined metabolic therapies targeting mTOR and glutaminase.

Clinical Responses to EGFr-TKI’s characterized by drug-induced cell death in human NSCLC primary cultures

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Background: Small molecule inhibitors of the EGFr have proven effective in advanced NSCLC but response rates in unselected populations remain low. Certain subsets of patients appear favored including females, non-smokers and Asians. Molecular profiles suggest that gene amplification or EGFr mutations (codons 19–21) may underlie responses. Our prior observations (Proc. AACR 2002, Abs.3902) indicated that gefitinib and erlotinib induced cell-death in human tumor microspheroids isolated from surgical specimens of some NSCLC patients, suggesting programmed cell death to be an important mechanism of action for these molecules. As part of an IRB-approved clinical trial, patients whose tumors were found sensitive to the EGFr-TKI’s by laboratory analysis, received 1st line single agent oral erlotinib at 150 mg/day. Methods: Following informed consent, NSCLC patients participating in the trial provided tissue for analysis as previously described (J Clin Oncol, 2000 18: 2245–2249). Dose response curves provided LC50 values by interpolation. Modified Z-score analysis identified patients sensitive to the EGFr-TKI’s by comparison with a database of over 900 EGFr-TKI analyses. Results: Three female caucasian patients were found more sensitive to EGFr-TKI’s than cytotoxic chemotherapy (2 non- & 1 former smoker). All 3 responded to erlotinib, 2 near-CR by PET, 1 lasting 19 months, the 2nd continuing at 10 months, with a 3rd patient in continuous PR at month 6. Toxicities have been moderate. One near-CR had virtually no skin rash. The molecular profile of 1 near-CR revealed no known gain of function mutation but instead a novel mutation in the EGFr domain. Conclusions: Exposure of human NSCLC microspheroids to EGFr-TKI’s in short term culture results in cell death events associated with clinical response, suggesting that programmed cell death is an important determinant of clinical response to these agents. This is consistent with the concept of oncogene addiction, in tumors driven by EGFr upregulation. Accrual to this trial continues. Supported by the Memorial Medical Center Foundation.

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A multicenter study of the efficacy of the ketogenic diet

OBJECTIVE

To determine the efficacy of the ketogenic diet in multiple centers.

DESIGN

A prospective study of the change in frequency of seizures in 51 children with intractable seizures who were treated with the ketogenic diet.

SETTING

Patients were enrolled from the clinical practices of 7 sites. The diet was initiated in-hospital and the patients were followed up for at least 6 months.

PATIENTS

Fifty-one children, aged 1 to 8 years, with more than 10 seizures per week, whose electroencephalogram showed generalized epileptiform abnormalities or multifocal spikes, and who had failed results when taking at least 2 appropriate anti-epileptic drugs.

INTERVENTION

The children were hospitalized, fasted, and a 4:1 ketogenic diet was initiated and maintained.

MAIN OUTCOME MEASURES

Frequency of seizures was documented from parental calendars and efficacy was compared with prediet baseline after 3, 6, and 12 months. The children were categorized as free of seizures, greater than 90% reduction, 50% to 90% reduction, or lower than 50% reduction in frequency of seizures.

RESULTS

Eighty-eight percent of all children initiating the diet remained on it at 3 months, 69% remained on it at 6 months, and 47% remained on it at 1 year. Three months after initiating the diet, frequency of seizures was decreased to greater than 50% in 54%. At 6 months, 28 (55%) of the 51 initiating the diet had at least a 50% decrease from baseline, and at 1 year, 40% of those starting the diet had a greater than 50% decrease in seizures. Five patients (10%) were free of seizures at 1 year. Age, sex, principal seizure type, and electroencephalogram were not statistically related to outcome.

CONCLUSION

The ketogenic diet is effective in substantially decreasing difficult-to-control seizures and can successfully be administered in a wide variety of settings.

Therapeutic goals and treatment options for prevention of stress ulcer syndrome

Stress ulcer syndrome, the occurrence of acute upper gastrointestinal bleeding or perforation from stress-related mucosal damage, is a significant cause of morbidity and mortality in critically ill patients. The mortality rate in critically ill patients who have bled from stress ulcers ranges from 50 to 77 percent, whereas the mortality rate for similar patients without stress ulcer bleeding ranges from 9 to 22 percent. The mortality rate may be as high as 90 percent in patients with clinically overt bleeding; as many as one-third of these deaths can be directly related to bleeding. Prophylactic therapy for prevention of stress ulcer bleeding is based on three premises: (1) morbidity and mortality related to stress ulcer syndrome are significant; (2) the population at risk can be identified prior to bleeding; and (3) therapy that decreases gastric acidity or improves gastric mucosal defense mechanisms will prevent ulcer formation or progression to bleeding. A review of prospective clinical studies utilizing prophylactic therapy in critically ill patients and patients undergoing surgery revealed a 17 percent overall bleeding rate for placebo groups compared with lower bleeding rates for antacid- and histamine (H2)-receptor-antagonist-treated groups (4 and 7 percent, respectively). Studies varied greatly in definition of bleeding, dosage regimens, and gastric pH goals. The need to measure gastric pH during treatment is controversial, and the optimal pH goal and the length of time for which it must be maintained remain unknown. Controversy exists as to the best therapeutic option for prophylaxis of stress ulcer syndrome, but when prevention of clinically significant bleeding is the therapeutic goal, antacids and H2-receptor antagonists appear to be equally efficacious.

Chitosan: a new topical hemostatic agent for diffuse capillary bleeding in brain tissue

The effectiveness of chitosan as an intraoperative topical hemostatic agent for brain tissue was tested. Cerebral cortical lesions were made in 10 cats. Chitosan was used to obtain hemostasis. The elapsed time from the application of the hemostatic agent to hemostasis was determined. The animals were killed and the lesions were examined grossly and microscopically to evaluate the biocompatibility of chitosan. Chitosan was easy to apply and required minimal subsequent manipulation. Histopathological examination revealed that chitosan is biocompatible with cerebral cortex.

Metkephamid, a systemically active analog of methionine enkephalin with potent opioid alpha-receptor activity

Metkephamid is an analog of methionine enkephalin that retains high affinity for the delta receptor and is a systemically active analgesic. Since it is at least 100 times more potent than morphine as an analgesic when placed directly into the lateral ventricles, and is 30 to 100 times more potent on the delta receptor and yet is roughly equipotent on the mu receptor in vitro, it is concluded that it probably produces analgesia by action on delta receptors as well as, or rather than, on mu receptors. It has less tendency to produce respiratory depression, tolerance, and physical dependence than standard analgesics, and it is presently undergoing clinical trial.

Eighth nerve lipoma. Case report

A case of lipoma of the right eighth cranial nerve in the cerebellopontine angle (CPA) is presented. The patient had a clinical, diagnostic, surgical, and postoperative course similar to that of patients with other small CPA tumors. The literature on this rare CPA tumor is reviewed and discussed.

Rat mammary gland atypia produced by iodine blockade with perchlorate

Prior published work from our laboratory concluded that there was a need for appropriate metabolic activity of iodine in breast tissue for normal growth and development. Results from studies in rats that were made iodine deficient showed histological changes in the breasts that were atypical and dysplastic. These tissue findings were further affected by the presence of estrogen and thyroxine. These changes parallel the iodine uptake of the tissues, thus representing a difference in the utilization of iodine by the mammary glands. Using an ion blockade agent, sodium perchlorate, breast tissues lacking iodine were evaluated by both endocrine and histological techniques. A dose-response series was completed that showed that perchlorate therapy for 8 weeks at 400 mg/100 ml produced breast blockade by a reduction in iodine uptake of greater than 52% of the control. At these levels, the histological experimentation showed atypia and some pleomorphism of the cells, particularly in the glands of the lobules. Blockade was less effective in estrogen-treated groups. It is especially notable that both histological changes and uptake reduction were greatest in those breasts that had been rendered euthyroid by thyroxine replacement, thus clearly indicating the necessity of iodine itself for maintenance of normal breast development. By this blockade the responses of iodine inadequacy in the breast were shown to cause abnormal tissue changes relative to the percentage of the block obtained.