Long-term Treatment Schedules Research Articles

A shea butter-based ketamine ointment: The antidepressant effects of transdermal ketamine in rats

The delayed onset of monoaminergic antidepressants and disadvantages of traditional administration routes created the need for alternative non-invasive delivery methods with rapid onset therapeutic effect. Ketamine attracted attention as a fast-acting glutamatergic antidepressant with ideal physiochemical properties for alternative routes of administration. However, there is no sufficient data for its transdermal use in depression. In this proof-of-concept study, we investigated the antidepressant effects of transdermal ketamine delivered via a novel ointment with skin protective, emulsifying and permeation enhancing properties. A shea butter-based 5% (w/w) ketamine ointment or a drug-free vehicle ointment were applied to the shaved dorsal skin of male Wistar rats for 2 days, twice a day. Behavioral despair, locomotor activity and anxiety-like behavior were respectively assessed in the forced swim test (FST), open field test (OFT), and elevated plus maze (EPM). The pharmacokinetic profile of the ointment was analyzed with high-performance liquid chromatography. Transdermal ketamine ameliorated behavioral despair without altering general locomotor activity and anxiety-like behavior, showing that skin-friendly drug carriers like shea butter may constitute promising alternatives to current routes of delivery for ketamine. Tested transdermal method aims to provide more sustainable drug delivery for long-term treatment schedules. Future studies can investigate its long-term use, side effects and abuse liability.

Combinatorial approaches for mitigating resistance to KRAS-targeted therapies.

Approximately 15% of all cancer patients harbor mutated KRAS. Direct inhibitors of KRAS have now been generated and are beginning to make progress through clinical trials. These include a suite of inhibitors targeting the KRASG12C mutation commonly found in lung cancer. We investigated emergent resistance to representative examples of different classes of Ras targeted therapies. They all exhibited rapid reactivation of Ras signaling within days of exposure and adaptive responses continued to change over long-term treatment schedules. Whilst the gene signatures were distinct for each inhibitor, they commonly involved up-regulation of upstream nodes promoting mutant and wild-type Ras activation. Experiments to reverse resistance unfortunately revealed frequent desensitization to members of a panel of anti-cancer therapeutics, suggesting that salvage approaches are unlikely to be feasible. Instead, we identified triple inhibitor combinations that resulted in more durable responses to KRAS inhibitors and that may benefit from further pre-clinical evaluation.

The effects of TENS, interferential stimulation, and combined interferential stimulation and pulsed ultrasound on patients with disc herniation-induced radicular pain.

Electrotherapy is part of a physician's toolbox for treating various musculoskeletal conditions, including radicular pain, but the preferred modality is yet unclear. To compare the short-term efficacy of three electrotherapeutic modalities in relieving lumbar disc herniation (LDH)-induced radicular pain. Fourteen patients with LDH-induced radicular pain attended a single session of electrotherapy, which included four 10-min consecutive treatments: transcutaneous electrical nerve stimulation (TENS), interferential (IF) stimulation, a combined treatment with pulsed ultrasound and IF current (CTPI), and a sham control. Treatments were randomized and the straight leg raise (SLR) degree was measured immediately before and after each treatment. Each of the three active modalities significantly improved the SLR score. The most prominent improvement was observed in the CTPI condition, followed by IF and, finally, TENS. The sham stimulation did not affect the SLR scores. A single session with either TENS, IF current or CTPI is sufficient to improve the range of motion and degree of radicular pain associated with LDH. CTPI appears to be the most effective modality of the three, possibly due to greater penetration efficiency of the induced current. The effects of a long-term treatment schedule are yet to be identified.

Effects of sequentially applied single and combined temozolomide, hydroxychloroquine and AT101 treatment in a long-term stimulation glioblastoma in vitro model.

Glioblastoma multiforme (GBM) is a poorly curable disease due to its heterogeneity that enables single cells to survive treatment regimen and initiate tumor regrowth. Although some progress in therapy has been achieved in the last years, the efficient treatment of GBMs is still a clinical challenge. Besides the standard therapeutic drug temozolomide (TMZ), quinoline-based antimalarial drugs such as hydroxychloroquine (HCQ) and BH3 mimetics such as AT101 were considered as possible drugs for GBM therapy. We investigated the effects of sequentially applied single and combined TMZ, HCQ and AT101 treatments in a long-term stimulation GBM in vitro model. We performed all investigations in parallel in human astrocytes and two differentially TMZ-responsive human GBM cell lines and adjusted used drug concentrations to known liquor/plasma concentrations in patients. We determined amounts of dead cells and still remaining growth rates and depicted our results in a heatmap-like summary to visualize which sequential long-term treatment schedule seemed to be most promising. We showed that sequential stimulations yielded higher cytotoxicity and better tumor growth control in comparison to single TMZ treatment. This was especially the case for the sequences TMZ/HCQ and TMZ + AT101/AT101 which was as effective as the non-sequential combination TMZ + AT101. Importantly, those affected both less and more TMZ-responsive glioma cell lines, whilst being less harmful for astrocytes in comparison to single TMZ treatment. Sequential treatment with mechanistically different acting drugs might be an option to reduce side effects in long-term treatment, for example in local administration approaches.

Deciphering molecular mechanisms of arginine deiminase-based therapy – Comparative response analysis in paired human primary and recurrent glioblastomas

Arginine auxotrophy constitutes the Achilles' heel for several tumors, among them glioblastoma multiforme (GBM). Hence, arginine-depleting enzymes such as arginine deiminase (ADI) from Streptococcus pyogenes are promising for treatment of primary and maybe even refractory GBM. Based on our previous study in which ADI-susceptibility was shown on a panel of patient-derived GBM cell lines, we here aimed at deciphering underlying molecular mechanisms of ADI-mediated growth inhibition. We found that ADI (35 mU/mL) initially induces a cellular stress-response that is characterized by upregulation of genes primarily belonging to the heat-shock protein family. In addition to autophagocytosis, we show for the first time that senescence constitutes another cellular response mechanism upon ADI-treatment and that this bacterial enzyme is able to act as radiosensitizer (¼ cases). Long-term treatment schedules revealed no resistance development, with treated cells showing morphological signs of cell stress. Next, several combination strategies were employed to optimize ADI-based treatment. Simultaneous and sequential S. pyogenes ADI-based combinations included substances acting at different molecular pathways (curcumin, resveratrol, quinacrine, and sorafenib, 2 × 72 h treatment). Adding drugs to GBM cell lines (n = 4, including a matched pair of primary and recurrent GBM in one case) accelerated and potentiated ADI-mediated cytotoxicity. Autophagy was identified as the main cause of tumor growth inhibition. Of note, residual cells again showed classical signs of senescence in most combinations.Our results suggest an alternative treatment regimen for this fatal cancer type which circumvents many of the traditional barriers. Using the metabolic defect in GBM thus warrants further (pre-) clinical evaluation.

89 - Preclinical validation of a novel compound targeting p70S6 kinase in breast cancer

UNLABELLED Breast cancer is a frequent and treatable disease. However, when recurrent, breast cancer often becomes refractory to therapy and progresses into metastatic forms that are typically incurable. Thus, understanding and targeting the critical pathways underlying breast cancer recurrence is urgently needed to eradicate primary disease and achieve better prognosis. Recently, we have demonstrated that the ribosomal protein p70S6K is activated in residual breast cancer cells as a result of post-surgical inflammation and that interfering with its activity in the peri-operative setting strongly suppresses recurrence in a mouse model. In order to develop clinically-exploitable treatments targeting p70S6K, we have tested a newly generated compound, called FS-115. FS-115 potently inhibited p70S6K1 (IC50 35nM) with high selectivity over other AGC kinases or PI3K pathway kinases. In vitro, treatment with FS-115 efficiently blocked p70S6K activity in breast cancer cell lines and impaired colony formation and anchorage independent growth. Pharmacokinetic profiling showed that FS-115 exhibited high oral bioavailability, optimal plasma distribution and high brain penetrance. In nude mice, FS-115 strongly suppressed tumor take-rate and primary tumor growth. Oral dosing with FS-115 in a peri-operative schedule was effective in decreasing local recurrence of breast cancer and a long-term treatment schedule was well tolerated and efficiently suppressed distant metastasis formation. Altogether, we propose that FS-115 might be a good candidate for the treatment of breast cancer patients at high risk to relapse. SUMMARY STATEMENT Our results confirm that inhibition of p70S6K represents a valuable opportunity for restraining loco-regional relapse and metastasis in breast cancer and identify in FS-115 a promising candidate-inhibitor to move from preclinical to clinical treatments.

Preclinical validation of a novel compound targeting p70S6 kinase in breast cancer.

Breast cancer is a frequent and treatable disease. However, when recurrent, breast cancer often becomes refractory to therapy and progresses into metastatic forms that are typically incurable. Thus, understanding and targeting the critical pathways underlying breast cancer recurrence is urgently needed to eradicate primary disease and achieve better prognosis. Recently, we have demonstrated that the ribosomal protein p70S6K is activated in residual breast cancer cells as a result of post-surgical inflammation and that interfering with its activity in the peri-operative setting strongly suppresses recurrence in a mouse model. In order to develop clinically-exploitable treatments targeting p70S6K, we have tested a newly generated compound, called FS-115. FS-115 potently inhibited p70S6K1 (IC50 35nM) with high selectivity over other AGC kinases or PI3K pathway kinases. In vitro, treatment with FS-115 efficiently blocked p70S6K activity in breast cancer cell lines and impaired colony formation and anchorage independent growth. Pharmacokinetic profiling showed that FS-115 exhibited high oral bioavailability, optimal plasma distribution and high brain penetrance. In nude mice, FS-115 strongly suppressed tumor take-rate and primary tumor growth. Oral dosing with FS-115 in a peri-operative schedule was effective in decreasing local recurrence of breast cancer and a long-term treatment schedule was well tolerated and efficiently suppressed distant metastasis formation. Altogether, we propose that FS-115 might be a good candidate for the treatment of breast cancer patients at high risk to relapse.Summary StatementOur results confirm that inhibition of p70S6K represents a valuable opportunity for restraining loco-regional relapse and metastasis in breast cancer and identify in FS-115 a promising candidate-inhibitor to move from preclinical to clinical treatments.

Antidiabetic effects of Eugenia jambolana in the streptozotocin-induced diabetic male albino rat

Presently, no satisfactory effective treatment is available to cure diabetes mellitus. Although synthetic drugs are used, there are several drawbacks. The attributed antihyperglycemic effects of many traditional plants are due to their ability for the management of diabetes mellitus. This study aimed to investigate the antidiabetic effect of the ethyl acetate fraction of the seed of Eugenia jambolana in streptozotocin-induced diabetic male albino rats. Diabetic rats were treated with this fraction at a dose of 200 mg/kg/d for 35 days. Potential antidiabetic mechanisms were investigated with blood glucose (short-term and long-term model), serum insulin, glycated hemoglobin, study of in situ end-labeling in pancreatic tissue, quantitative reverse transcription polymerase chain reaction, followed by western blotting study to assess the hepatic hexokinase-I gene expression, and in-vitro assessment of intestinal maltase and sucrase activity. Results showed a significant antihyperglycemic action in both short-term and long-term treatment schedules. Serum insulin and glycated hemoglobin levels were also recovered in the treated group in comparison with the untreated diabetic group (p < 0.05). In situ end-labeling study focused on the regeneration of pancreatic beta cells in the treated group. We also observed the correction of expression of the hepatic hexokinase-I gene after the treatment of the fraction in diabetic rats. Intestinal maltase and sucrase activities also displayed inhibition activity in the presence of ethyl acetate fraction. The antidiabetic activity of the fraction was compared with glibenclamide, a standard antidiabetic drug. The findings provide information about the antihyperglycemic activity of this fraction through gene regulation.

Efalizumab in the treatment of psoriasis: when comorbidity is an issue

Psoriasis is a common dermatosis affecting the skin, mucosal surfaces, and cutaneous adnexa, and joints and bones can be involved at some degree in the clinical features of the disease, configuring psoriatic arthritis. Moderate to severe psoriasis has a high impact on quality of life and requires an integrated and long-term treatment schedule. However, management of psoriasis in patients affected by other systemic diseases can be challenging because of the possible side effects or contraindications of various treatments in accordance with patients' medical history. In recent times, the therapeutical approaches have changed a lot, thanks to biologicals. The current authors present some cases of psoriatic patients with comorbidities successfully treated with efalizumab, an anti-T lymphocyte biological.

Perinatal alcohol exposure enhances nocistatin levels in adulthood

In earlier experiments perinatal hormonal imprinting by alcohol decreased the hormone content of immune cells for life. In the present study, both a single day (15% on the third postnatal day) and a long-term treatment schedule of alcohol exposure (3% for 21 days) of dams during lactation significantly (P < 0.01) enhanced endogenous levels of nocistatin in the blood plasma as well as in the cerebrospinal fluid of the offspring, measured in 3-month-old rats. Our data suggest that alcohol consumption during lactation can cause a life-long influence on nocistatin levels in the offspring and most likely modify nocistatin-related functions such as pain tolerance.

Relationship between serum b2-microglobulin levels and virological breakthrough in HBeAg-negative chronic hepatitis B patients, under long-term treatment schedules including lamivudine

Predictive value of serum b2-microglobulin (b2m) levels for virological breakthrough (VB) in HBeAg-negative chronic hepatitis B (CHB) patients under long-term treatment schedules including lamivudine (LAM). Serum b2m levels were calculated during treatment in 25 CHB patients under long-term LAM monotherapy (group A) and 12 patients under initial interferon plus LAM treatment followed by LAM monotherapy (group B), using the MEIA technology. We used Cox proportional hazard models in order to investigate the association between serum b2m levels and VB. Seven of 25 patients (28%), 9/25 (36%) and 14/25 (56%) from group A and 0/12, 2/12 (16.6%) and 3/12 (25%) from group B exhibited VB at months 12, 24 and 36 of treatment, respectively. All patients, from both groups, who did not show VB exhibited b2m elevation in mo 3. The duration of b2m elevation was significantly longer in the virological responder's subgroup from group A than the non-responder's one (7.3+/-2.6 vs 3.8+/-3.4 mo, P = 0.02). In comparison to group A patients whose b2m levels were increased at 3 mo, patients whose b2m levels were decreased had 4.6 times higher risk of experiencing VB (RR = 4.6, P = 0.024). When baseline variables were simultaneously included in the same Cox model, decreased b2m status was still associated with increased risk of VB (RR = 12.2, P = 0.03). In HBeAg-negative CHB patients under either long-term LAM monotherapy or initial combination treatment, serum b2m levels at 3 mo of treatment, compared to baseline ones, might be a predictor of risk for VB.

The role of tamoxifen in the treatment and prevention of breast cancer

Tamoxifen is a nonsteroidal antiestrogen that has found successful applications for each stage of breast cancer in the treatment of selected patients. Tamoxifen was originally introduced for the treatment of advanced disease in postmenopausal women; however, the drug is now also available for the palliative treatment of premenopausal women with estrogen receptor (ER) positive disease. The proven efficacy of tamoxifen and the low incidence of side effects made the drug an ideal agent to test as an adjuvant therapy for women with node-positive breast cancer. Laboratory studies indicate that long-term treatment schedules may provide maximal benefit in preventing recurrence, and recent analysis of clinical trials demonstrates that between 2 and 5 years of adjuvant tamoxifen therapy provides a survival advantage for postmenopausal women with node-positive disease. Similarly, adjuvant studies in node-negative breast cancer have demonstrated an increase in the disease-free survival of both pre- and postmenopausal patients with ER-positive tumors. However, the extended use of tamoxifen has raised questions about the long-term safety of antiestrogen therapy. Of special concern is the impact of tamoxifen on ovarian function in premenopausal women and the potential risks to the fetus if pregnancy occurs. Fortunately, there are no reports about the teratogenicity of tamoxifen in the human, but it is important that physicians counsel women about the risk of pregnancy. Tamoxifen should not be used if a patient is pregnant. Initial concerns that the long-term administration of an antiestrogen would increase bone loss and increase the risks of coronary heart disease appear to be unwarranted. Tamoxifen has some estogen-like activities in postmenopausal women and causes a preservation of bone in the lumbar spine and decrease in circulating cholesterol. Indeed, a reduction in fatal myocardial infarction (MI) has been noted during 5 years of tamoxifen therapy, possibly the direct result of a prolonged reduction in circulating cholesterol. However, the estrogen-like qualities of tamoxifen that could be valuable as a hormone replacement therapy for all postmenopausal women following a diagnosis of breast cancer may also increase the risk for developing endometrial carcinoma. To date, there are only a few reports of endometrial carcinoma being diagnosed during adjuvant therapy with tamoxifen; however, any instances of uterine bleeding or spotting should be followed up with an endometrial biopsy. There are some concerns about large doses of tamoxifen promoting liver cancer in rats. These results are of particular concern if tamoxifen is to be used as a preventive in normal women. However, tamoxifen is acting as a weak estrogen in the rat model, and other estrogens (eg, conjugated estrogens and estrogens used in oral contraceptives) are much more potent promoters of liver cancer. There are no reports of an increased incidence of hepatocellular carcinoma during long-term tamoxifen therapy; in fact, there is a report of the use of tamoxifen to treat the disease successfully. The estrogen-like properties of tamoxifen may encourage clones of breast cancer cells to grow in response to the drug. This form of drug resistance has been described in the laboratory, and a new pure antiestrogen is being evaluated for use as a second-line agent following the failure of long-term adjuvant tamoxifen therapy. The extensive clinical experience with tamoxifen has encouraged its evaluation as a preventive in women at risk of developing breast cancer. Several clinical studies are being positioned in different countries to address this question. All the laboratory studies demonstrate that tamoxifen will prevent or suppress mammary cancer, and clinical experience has shown a 40% reduction in the incidence of second primary breast cancers. The completion of randomized prevention trials with tamoxifen will place a valuable medical option in the hands of the physician who treats women at risk for breast cancer.

Steroid sensitivity of thymocyte subpopulations during intrathymic differentiation. Effects of 17 beta-estradiol and dexamethasone on subsets expressing T cell antigen receptor or IL-2 receptor.

We have studied the effects of the steroid hormones, 17 beta-estradiol and dexamethasone, on the relative proportion of thymocyte expression of CD4 (L3T4), CD8 (Ly-2), TCR and IL-2R, used to identify different stages of thymocyte differentiation. After short-term in vivo steroid treatment, a significant decrease in the number and proportion of the CD4+/CD8+, double positive subpopulation was observed in parallel with a proportional increase in the percentage of the CD4+/CD8- single positive, of the CD4-/CD8-, double negative and, to a lesser extent, of the CD8+/CD4- subsets. Either steroid treatment increased the proportion of cells expressing either the epsilon-chain of the CD3 complex and/or the beta-chain of the TCR (beta-TCR) (TCR+/CD3+) and the 55 kDa protein of the IL-2R (IL-2R+), related to the increase of CD4+ SP thymocytes and of DN cells, respectively. Furthermore, the increased proportion of CD3+ cells could also be partially related to the increase of both the CD4+ and DN subsets. A decrease of the effect on either DN/IL-2R+ cells or CD4+ SP cells was selectively observed after long-term treatments with 17 beta-estradiol or DEX, respectively. It is concluded that after short-term administration, different steroid hormones mediate a similar selective depletion of DP, TCR-/CD3-, IL2R- cells presumably in an intermediate stage of differentiation. However, either steroid effects evolve differently in long-term treatment schedules, resulting in different effects on early (DN/IL2R+) and late (SP/IL2R-) steps of thymocyte differentiation.

Adverse reactions in long-term interferon treatment.

Adverse reactions in interferon treatment were studied in long-term treatment schedules. Thirteen patients with metastatic renal cell carcinoma treated with 10(7) units interferon-2b s.c. daily for 6 months showed serious side effects. The general condition worsened in 10 patients. The average weight loss was 7 kg per patient. The remissions achieved (1 complete, 2 partial) were seen after 2-3 months of treatment. In 11 patients treated in an adjunctive setting (10(7) units interferon-2b s.c. 3 times weekly) side effects were less severe. Generally the treatment was tolerated well. In one patient the general condition worsened, weight loss was mild and restricted to the first treatment month.