Megestrol acetate: clinical experience

Comprehensive pan-cancer investigation: unraveling the oncogenic, prognostic, and immunological significance of Abelson interactor family member 3 gene in human malignancies

Background: Abelson interactor Family Member 3 (ABI3) encodes protein that not only suppresses the ectopic metastasis of tumor cells but also hinders their migration. Although ABI3 had been found to modulate the advancement of diverse neoplasms, there is no comprehensive pan-cancer analysis of its effects. Methods: The transcriptomics data of neoplasm and normal tissues were retrieved from the Genomic Data Commons (GDC) data portal, and UCSC XENA database. To gather protein information for ABI3, Human Protein Atlas (HPA) and GeneMANIA websites were utilized. Additionally, Tumor Immune Single-cell Hub (TISCH) database was consulted to determine the primary cell types expressing ABI3 in cancer microenvironments. Univariate Cox regression approach was leveraged to evaluate ABI3's prognostic role across cancers. The Cbioportal and Gene Set Cancer Analysis (GSCA) website were leveraged to scrutinize the genomic landscape information across cancers. TIMER2.0 was leveraged to probe the immune cell infiltrations associated with ABI3 across cancers. The associations of ABI3 with immune-related genes were analyzed through Spearman correlation method. Gene Set Enrichment Analysis (GSEA) and Gene Set Variation Analysis (GSVA) were utilized to search associated biological pathways. The CellMiner database and molecular docking were implemented to identify potential interactions between the ABI3 protein and specific anticarcinogen. Findings: ABI3 expression and its ability to predict prognosis varied distinct tumor, with particularly high expression observed in Tprolif cells and monocytes/macrophages. Copy number variation (CNV) and methylation negatively correlated with ABI3 expression in the majority of malignancies. Corresponding mutation survival analysis indicated that the mutation status of ABI3 was strongly connected to the prognosis of LGG patients. ABI3 expression was linked to immunotherapeutic biomarkers and response in cancers. ESTIMATE and immune infiltrations analyses presented ABI3 association with immunosuppression. ABI3 was significantly correlated with immunoregulators and immune-related pathways. Lastly, prospective ABI3-targeted drugs were filtered and docked to ABI3 protein. Interpretation: Our study reveals that ABI3 acts as a robust tumor biomarker. Its functions are vital that could inhibit ectopic metastasis of tumor cells and modulate cellular adhesion and migration. The discoveries presented here may have noteworthy consequences for the creation of fresh anticancer suppressors, especially those targeting BRCA.

A review of FDA approved drugs and their formulations for the treatment of breast cancer

Breast cancer is one of the most diagnosed solid cancers globally. Extensive research has been going on for decades to meet the challenges of treating solid tumors with selective compounds. This article aims to summarize the therapeutic agents which are either being used or are currently under approval for use in the treatment or mitigation of breast cancer by the US FDA, to date. A structured search of bibliographic databases for previously published peer-reviewed research papers on registered molecules was explored and data was sorted in terms of various categories of drugs used in first line/adjuvant therapy for different stages of breast cancer. We included more than 300 peer-reviewed papers, including both research and reviews articles, in order to provide readers an useful comprehensive information. A list of 39 drugs are discussed along with their current status, dose protocols, mechanism of action, pharmacokinetics, possible side effects, and marketed formulations. Another interesting aspect of the article included focusing on novel formulations of these drugs which are currently in clinical trials or in the process of approval. This exhaustive review thus shall be a one-stop solution for researchers who are working in the areas of formulation development for these drugs.

Does Therapeutic Repurposing in Cancer Meet the Expectations of Having Drugs at a Lower Price?

Therapeutic repurposing emerged as an alternative to the traditional drug discovery and development model (DDD) of new molecular entities (NMEs). It was anticipated that by being faster, safer, and cheaper, the development would result in lower-cost drugs. As defined in this work, a repurposed cancer drug is one approved by a health regulatory authority against a non-cancer indication that then gains new approval for cancer. With this definition, only three drugs are repurposed for cancer: Bacillus Calmette-Guerin (BCG) vaccine (superficial bladder cancer, thalidomide [multiple myeloma], and propranolol [infantile hemangioma]). Each of these has a different history regarding price and affordability, and it is not yet possible to generalize the impact of drug repurposing on the final price to the patient. However, the development, including the price, does not differ significantly from an NME. For the end consumer, the product's price is unrelated to whether it followed the classical development or repurposing. Economic constraints for clinical development, and drug prescription biases for repurposing drugs, are barriers yet to be overcome. The affordability of cancer drugs is a complex issue that varies from country to country. Many alternatives for having affordable drugs have been put forward, however these measures have thus far failed and are, at best, palliative. There are no immediate solutions to the problem of access to cancer drugs. It is necessary to critically analyze the impact of the current drug development model and be creative in implementing new models that genuinely benefit society.

Polygonum cuspidatum Extract (Pc-Ex) Containing Emodin Suppresses Lung Cancer-Induced Cachexia by Suppressing TCF4/TWIST1 Complex-Induced PTHrP Expression

Cachexia, which is characterised by the wasting of fat and skeletal muscles, is the most common risk factor for increased mortality rates among patients with advanced lung cancer. PTHLH (parathyroid hormone-like hormone) is reported to be involved in the pathogenesis of cancer cachexia. However, the molecular mechanisms underlying the regulation of PTHLH expression and the inhibitors of PTHLH have not yet been identified. The PTHLH mRNA levels were measured using quantitative real-time polymerase chain reaction, while the PTHrP (parathyroid hormone-related protein) expression levels were measured using Western blotting and enzyme-linked immunosorbent assay. The interaction between TCF4 (Transcription Factor 4) and TWIST1 and the binding of the TCF4–TWIST1 complex to the PTHLH promoter were analysed using co-immunoprecipitation and chromatin immunoprecipitation. The results of the mammalian two-hybrid luciferase assay revealed that emodin inhibited TCF4–TWIST1 interaction. The effects of Polygonum cuspidatum extract (Pc-Ex), which contains emodin, on cachexia were investigated in vivo using A549 tumour-bearing mice. Ectopic expression of TCF4 upregulated PTHLH expression. Conversely, TCF4 knockdown downregulated PTHLH expression in lung cancer cells. The expression of PTHLH was upregulated in cells ectopically co-expressing TCF4 and TWIST1 when compared with that in cells expressing TCF4 or TWIST1 alone. Emodin inhibited the interaction between TCF4 and TWIST1 and consequently suppressed the TCF4/TWIST1 complex-induced upregulated mRNA and protein levels of PTHLH and PTHrP. Meanwhile, emodin-containing Pc-Ex significantly alleviated skeletal muscle atrophy and downregulated fat browning-related genes in A549 tumour-bearing mice. Emodin-containing Pc-Ex exerted therapeutic effects on lung cancer-associated cachexia by inhibiting TCF4/TWIST1 complex-induced PTHrP expression.

Effect and Mechanism of Herbal Medicines on Cisplatin-Induced Anorexia

Cisplatin is a well-known chemotherapeutic agent used to treat various types of cancers; however, it can also induce anorexia, which results in reduced food intake, loss of body weight, and lower quality of life. Although drugs such as megestrol acetate and cyproheptadine are used to decrease this severe feeding disorder, they can also induce side effects, such as diarrhea and somnolence, which limit their widespread use. Various types of herbal medicines have long been used to prevent and treat numerous gastrointestinal tract diseases; however, to date, no study has been conducted to analyze and summarize their effects on cisplatin-induced anorexia. In this paper, we analyze 12 animal studies that used either a single herbal medicine extract or mixtures thereof to decrease cisplatin-induced anorexia. Among the herbal medicines, Ginseng Radix was the most used, as it was included in seven studies, whereas both Glycyrrhizae Radix et Rhizoma and Angelicae Gigantis Radix were used in four studies. As for the mechanisms of action, the roles of serotonin and its receptors, cytokines, white blood cells, ghrelin, and leptin were investigated. Based on these results, we suggest that herbal medicines could be considered a useful treatment method for cisplatin-induced anorexia.

Megestrol acetate is a specific inducer of CYP3A4 mediated by human pregnane X receptor

PURPOSE

Megestrol acetate is a synthetic progestogen used to treat some cancers and cancer-associated cachexia, but its potential interactions with other drugs are not well known. This study aims to determine the regulation of drug metabolizing enzymes by megestrol acetate.

METHODS

Primary human hepatocytes were treated and analyzed by PCR array to identify genes involved in drug metabolism that are impacted by megestrol acetate. P450 3A4 (CYP3A4) reporter gene assay and HPLC analyses of nifedipine metabolites were used to determine CYP3A4 gene expression and activities. Competitive ligand binding assay was used to determine the affinity of megestrol acetate toward human pregnane x receptor (hPXR). Electrophoretic mobility shift assay and mammalian two hybrid assay were used to determine the mechanism of megestrol to activate hPXR.

RESULTS

The levels and activities of CYP3A4 were significantly induced (> 4-folds) by megestrol acetate in human hepatocytes and HepG2 cells. Megestrol treatment induced CYP3A4 through the activation of hPXR, a ligand-activated transcription factor that plays a role in drug metabolism and transport. Other tested nuclear receptors showed no response. The mechanism studies showed that megestrol activated hPXR by binding to the ligand binding domain (LBD) of hPXR and increasing the recruitment of the cofactors such as steroid receptor cofactor (SRC-1).

CONCLUSION

The results suggest that megestrol acetate is a specific inducer of CYP3A4 mediated by hPXR and therefore has the potential to cause drug interactions, especially in the co-administration with drugs that are substrates of CYP3A4.

Megestrol acetate drives endometrial carcinoma cell senescence via interacting with progesterone receptor B/FOXO1 axis

Megestrol acetate is a common and efficient anticancer progesterone. To explore the activity and the therapeutic mechanisms of megestrol acetate in endometrial cancer, human endometrial cancer cell lines Ishikawa and HHUA overexpressing progesterone receptor A (PR-A) and progesterone receptor B (PR-B) were treated with megestrol acetate. Cell viability, apoptosis, cycle arrest, and senescence, as well as the expressions of p21 and p16, two hallmarks of cellular senescence, were evaluated. Compared with the control, >10 nmol/L megestrol acetate treatment could significantly reduce endometrial cancer cell growth, and induce the irreversible G1 arrest and cell senescence. The expression of cyclin D1 in megestrol acetate treated cells was downregulated, while the expressions of p21 and p16 were upregulated via PR-B isoform. FOXO1 inhibitor AS1842856 could significantly abrogate megestrol acetate-induced cell senescence, suggesting that FOXO1 was involved in megestrol acetate/PR-B axis. These findings may provide a new understanding for the treatment of human endometrial cancer.

Risk prediction models for cancer-specific survival following cytoreductive nephrectomy in the contemporary era

INTRODUCTION

To develop a risk-stratification model for cancer-specific survival (CSS) following cytoreductive nephrectomy (CN) in the contemporary era.

MATERIALS AND METHODS

A retrospective review was performed of 313 patients who underwent CN for M1 renal cell carcinoma (RCC) from 1990 to 2010. To account for the introduction of targeted therapies, timing of surgery was classified as immunotherapy era (1990-2004) or contemporary era (2005-2010). Risk scores were developed to predict CSS using Cox proportional hazards regression models.

RESULTS

A total of 215 (69%) and 98 (31%) patients were treated in the immunotherapy and contemporary eras, respectively. Median follow-up among survivors was 9.6 years, during which time 291 patients died, including 279 from RCC. On multivariable analysis limited to preoperative features, age ≥ 75, (hazard ratio [HR] 1.9), female sex (HR 1.9), constitutional symptoms (HR 1.61), radiographic lymphadenopathy (HR 1.59), and IVC tumor thrombus (HR 1.65) were significantly associated with CSS. On multivariable analysis including pathologic features, the features above as well as coagulative necrosis (HR 1.51) and sarcomatoid differentiation (HR 1.44) were significantly associated with CSS (all P < 0.05). Risk scores were developed for each model and used to predict CSS according to era. Decision curve analysis revealed that the preoperative risk score conferred a net benefit over a treat-all or treat-none approach beyond a 1-year cancer-specific mortality threshold of 25%.

CONCLUSIONS

We developed risk scores to predict CSS for patients treated with CN in the contemporary era. Patients with poor predicted survival may consider avoiding CN as initial management.

Megestrol Acetate in Unresectable Hepatocellular Carcinoma

Aims and background

No consolidated medical treatment has yet been established for unresectable hepatocellular carcinoma (HCC). A possible interference of hormones in the pathogenesis and cellular growth of HCC has been suggested.

Methods

To evaluate the activity and tolerance of progestins in HCC, patients were treated with megestrol acetate orally at a dose of 160 mg daily until progression of disease or grade III-IV toxicity was observed.

Results

Eleven patients entered the study and were assessable for response and side effects. Median duration of treatment was 80 days (range 60-150). No major responses were observed, 4 patients had stabilization of disease for at least 2 months, and 7 had progressive disease. Median time to disease progression was 3 months (range 2-5). Three patients required interruption of treatment because of toxicity (2 patients had worsening of concomitant diabetes and 1 patient had gastric bleeding).

Conclusions

The results of the present study suggest that hormone therapy with megestrol acetate has no significant role in HCC.

Metabolism of megestrol acetate in vitro and the role of oxidative metabolites

1. There is limited knowledge regarding the metabolism of megestrol acetate (MA), as it was approved by FDA in 1971, prior to the availability of modern tools for identifying specific drug-metabolizing enzymes. We determined the cytochrome P450s (P450s) and UDP-glucuronosyltransferases (UGTs) that metabolize MA, identified oxidative metabolites and determined pharmacologic activity at the progesterone, androgen and glucocorticoid receptors (PR, AR and GR, respectively). 2. Oxidative metabolites were produced using human liver microsomes (HLMs), and isolated for mass spectral (MS) and nuclear magnetic resonance (NMR) analyses. We screened recombinant P450s using MA at 62 μM (HLM K_m for metabolite 1; M1) and 28 μM (HLM K_m for metabolite 2; M2). UGT isoforms were simultaneously incubated with UDPGA, nicotinamide adenine dinucleotide phosphate (NADPH), CYP3A4 and MA. Metabolites were evaluated for pharmacologic activity on the PR, AR and GR. CYP3A4 and CYP3A5 are responsible for oxidative metabolism of 62 μM MA. 3. At 28 μM substrate concentration, CYP3A4 was the only contributing enzyme. Mass spectral and NMR data suggest metabolism of MA to two alcohols. After oxidation, MA is converted into two secondary glucuronides by UGT2B17 among other UGTs. MA, M1 and M2 had significant pharmacologic activity on the PR while only MA showed activity on the AR and GR.

Tolerability and pharmacokinetics of two formulations of megestrol acetate under fed conditions in healthy volunteers

PURPOSE

Megestrol acetate oral suspension is an appetite stimulant indicated for cachexia. It is available in a conventional formulation and as a nanocrystal dispersion. The aim of this study was to compare the tolerability and pharmacokinetics of these formulations under fed conditions in healthy Korean volunteers.

METHODS

This was a randomized, single-dose, 3-treatment, 3-period, 6-sequence, crossover study in healthy Korean volunteers. In each period, participants received single oral doses of conventional formulation 800 mg/20 mL (reference), nanocrystal dispersion 650 mg/5.2 mL (test 1), and nanocrystal dispersion 675 mg/5.4 mL (test 2) after a high-calorie, high-fat meal. The periods were separated by a washout period of 14 days. Serial blood samples were collected up to 120 hours after dosing. The plasma concentrations of megestrol acetate were determined with a validated LC-MS/MS method. Pharmacokinetic parameters were obtained by noncompartmental analysis. Tolerability was assessed by physical examinations, vital signs, clinical laboratory test results, and electrocardiograms.

FINDINGS

Thirty-eight healthy volunteers completed the study. The geometric mean ratios of the AUC(last) and C(max) for test 1/reference were 0.88 (90% CI, 0.84-0.92) and 1.07 (90% CI, 0.99-1.15), respectively. The geometric mean ratios of the AUC(last) and C(max) for test 2/reference were 0.88 (90% CI, 0.84-0.93) and1.03 (90% CI, 0.96-1.10), respectively. All formulations were well tolerated.

IMPLICATIONS

The pharmacokinetic characteristics and tolerability of the 2 megestrol acetate formulations are similar in fed volunteers and suggest no relevant difference in tolerability. ClinicalTrials.gov identifier: NCT01342055.

Towards engineering hormone-binding globulins as drug delivery agents

The treatment of many diseases such as cancer requires the use of drugs that can cause severe side effects. Off-target toxicity can often be reduced simply by directing the drugs specifically to sites of diseases. Amidst increasingly sophisticated methods of targeted drug delivery, we observed that Nature has already evolved elegant means of sending biological molecules to where they are needed. One such example is corticosteroid binding globulin (CBG), the major carrier of the anti-inflammatory hormone, cortisol. Targeted release of cortisol is triggered by cleavage of CBG's reactive centre loop by elastase, a protease released by neutrophils in inflamed tissues. This work aimed to establish the feasibility of exploiting this mechanism to carry therapeutic agents to defined locations. The reactive centre loop of CBG was altered with site-directed mutagenesis to favour cleavage by other proteases, to alter the sites at which it would release its cargo. Mutagenesis succeeded in making CBG a substrate for either prostate specific antigen (PSA), a prostate-specific serine protease, or thrombin, a key protease in the blood coagulation cascade. PSA is conspicuously overproduced in prostatic hyperplasia and is, therefore, a good way of targeting hyperplastic prostate tissues. Thrombin is released during clotting and consequently is ideal for conferring specificity to thrombotic sites. Using fluorescence-based titration assays, we also showed that CBG can be engineered to bind a new compound, thyroxine-6-carboxyfluorescein, instead of its physiological ligand, cortisol, thereby demonstrating that it is possible to tailor the hormone binding site to deliver a therapeutic drug. In addition, we proved that the efficiency with which CBG releases bound ligand can be increased by introducing some well-placed mutations. This proof-of-concept study has raised the prospect of a novel means of targeted drug delivery, using the serpin conformational change to combat the problem of off-target effects in the treatment of diseases.

Progesterone as a morphological regulatory factor of the male and female gerbil prostate

Testosterone (T) and oestrogen are the main active steroid hormones in the male and female reproductive system respectively. In female rodents progesterone (P4), together with testosterone and oestrogen, has an essential role in the regulation of the oestrous cycle, which influences the prostate physiology through their oscillations. In this work we investigated how the male and female prostate gland of Mongolian gerbils responds to surgical castration at the start of puberty and what are the effects of T, oestradiol (E2) and P4 replacement, using both quantitative and qualitative methods. We also examined the location of the main steroid receptors present in the prostate. In the castrated animals of both sexes an intense glandular regression, along with disorganization of the stromal compartment, and abundant hyperplasia was observed. The replacement of P4 secured a mild recovery of the glandular morphology, inducing the growth of secretory cells and restoring the androgen receptor (AR) cells. The administration of P4 and E2 eliminated epithelial hyperplasia and intensified gland hypertrophy, favouring the emergence of prostatic intraepithelial neoplasia (PIN). In animals treated with T and P4, even though there are some inflammatory foci and other lesions, the prostate gland revealed morphology closer to that of control animals. In summary, through the administration of P4, we could demonstrate that this hormone has anabolic characteristics, promoting hyperplasia and hypertrophy, mainly in the epithelial compartment. When combined with E2 and T, there is an accentuation of glandular hypertrophy that interrupts the development of hyperplasia and ensures the presence of a less dysplastic glandular morphology.

Megestrol acetate for treatment of anorexia-cachexia syndrome

BACKGROUND

This is an updated version of a previously published review in The Cochrane Library (2005, Issue 2) on 'Megestrol acetate for the treatment of anorexia-cachexia syndrome'. Megestrol acetate (MA) is currently used to improve appetite and to increase weight in cancer-associated anorexia. In 1993, MA was approved by the US Food and Drug Administration for the treatment of anorexia, cachexia or unexplained weight loss in patients with AIDS. The mechanism by which MA increases appetite is unknown and its effectiveness for anorexia and cachexia in neoplastic and AIDS (acquired immunodeficiency syndrome) patients is under investigation.

OBJECTIVES

To evaluate the efficacy, effectiveness and safety of MA in palliating anorexia-cachexia syndrome in patients with cancer, AIDS and other underlying pathologies.

SEARCH METHODS

We sought studies through an extensive search of electronic databases, journals, reference lists, contact with investigators and other search strategies outlined in the methods. The most recent search for this update was carried out in May 2012.

SELECTION CRITERIA

Studies were included in the review if they assessed MA compared to placebo or other drug treatments in randomised controlled trials of patients with a clinical diagnosis of anorexia-cachexia syndrome related to cancer, AIDS or any other underlying pathology.

DATA COLLECTION AND ANALYSIS

Two independent review authors conducted data extraction and evaluated methodological quality. We performed quantitative analyses using appetite and quality of life as a dichotomous variable, and analysed weight gain as continuous and dichotomous variables.

MAIN RESULTS

We included 35 trials in this update, the same number but not the same trials as in the previous version of the review. The trials comprised 3963 patients for effectiveness and 3180 for safety. Sixteen trials compared MA at different doses with placebo, seven trials compared different doses of MA with other drug treatments and 10 trials compared different doses of MA. Meta-analysis showed a benefit of MA compared with placebo, particularly with regard to appetite improvement and weight gain in cancer, AIDS and other underlying conditions, and lack of benefit in the same patients when MA was compared to other drugs. There was insufficient information to define the optimal dose of MA, but higher doses were more related to weight improvement than lower doses. Quality of life improvement in patients was seen only when comparing MA versus placebo but not other drugs in both subcategories: cancer and AIDS. Oedema, thromboembolic phenomena and deaths were more frequent in the patients treated with MA. More than 40 side effects were studied.

AUTHORS' CONCLUSIONS

This review shows that MA improves appetite and is associated with slight weight gain in cancer, AIDS and in patients with other underlying pathology. Despite the fact that these patients are receiving palliative care they should be informed of the risks involved in taking MA.

Novel actions of progesterone: what we know today and what will be the scenario in the future?

Objectives

This article is aimed to review the novel actions of progesterone, which otherwise is considered as a female reproductive hormone. The article focuses on its important physiological actions in males too and gives an overview of its novel perspectives in disorders of central and peripheral nervous system.

Key findings

Progesterone may have a potential benefit in treatment of traumatic brain injury, various neurological disorders and male related diseases like benign prostatic hypertrophy (BPH), prostate cancer and osteoporosis. Norethisterone (NETA), a progesterone derivative, decreases bone mineral loss in male castrated mice suggesting its role in osteoporosis. In the future, progesterone may find use as a male contraceptive too, but still needs confirmatory trials for safety, tolerability and acceptability. Megestrol acetate, a progesterone derivative is preferred in prostatic cancer. Further, it may find utility in nicotine addiction, traumatic brain injury (recently entered Phase III trial) and Alzheimer's disease, diabetic neuropathy and crush injuries. Studies also suggest role of progesterone in stroke, for which further clinical trials are needed. The non genomic actions of progesterone may be in part responsible for these novel actions.

Summary

Although progesterone has shown promising role in various non-hormonal benefits, further clinical studies are needed to prove its usefulness in conditions like stroke, traumatic brain injury, neuropathy and crush injury. In male related illnesses like BPH and prostatic Ca, it may prove a boon in near future. New era of hormonal male contraception may be initiated by use of progesterone along with testosterone.

Renal cell carcinoma: Current status and future prospects

The incidence of renal cell carcinoma (RCC) is increasing. Despite improvements in the management of localized RCC, most patients are diagnosed with advanced RCC, which is often refractory and associated with a poor prognosis. Although surgery is the only curative treatment for localized RCC, improved diagnostic methods facilitating early detection and characterization of renal tumors have enabled more effective use of less invasive treatments. Adrenal-sparing radical total nephrectomy, and laparoscopic radical and total nephrectomy are increasingly being performed in preference to radical nephrectomy. However, standard treatments for advanced RCC are largely unsuccessful. Radiotherapy is often used to control symptoms associated with RCC in patients unsuitable for surgery. Immunotherapy with cytokines is the standard systemic treatment for advanced RCC, and is associated with prolonged survival in a subset of patients, but is generally poorly tolerated. An increased knowledge of the underlying pathophysiology of RCC has resulted in the identification of molecular pathways involved in tumor growth. Promising new agents designed to target these pathways are in development.

The science of megestrol acetate delivery: potential to improve outcomes in cachexia

Cachexia, usually defined as the loss of >5% of an individual's baseline bodyweight over 2-6 months, occurs with a number of diseases that includes not only AIDS and advanced cancer but also chronic heart failure, rheumatoid arthritis, chronic obstructive pulmonary disease, Crohn disease, and renal failure. Anorexia is considered a key component of the anorexia-cachexia syndrome. Progestogens, particularly megestrol acetate, are commonly used to treat anorexia-cachexia. The mechanism of action of megestrol is believed to involve stimulation of appetite by both direct and indirect pathways and antagonism of the metabolic effects of the principal catabolic cytokines. Because the bioavailability of megestrol acetate directly affects its efficacy and safety, the formulation was refined to enhance its pharmacokinetics. Such efforts yielded megestrol acetate in a tablet form, followed by a concentrated oral suspension form, and an oral suspension form developed using nanocrystal technology. Nanocrystal technology was designed specifically to optimize drug delivery and enhance the bioavailability of drugs that have poor solubility in water. Megestrol acetate nanocrystal oral suspension is currently under review by the US FDA for the treatment of cachexia in patients with AIDS. Preclinical pharmacokinetic data suggest that the new megestrol acetate formulation has the potential to significantly shorten the time to clinical response and thus may improve outcomes in patients with anorexia-cachexia.

The effect of megestrol acetate on growth of HepG2 cells in vitro and in vivo

PURPOSE

Hepatocellular carcinoma (HCC) is generally considered as a sex hormone-dependent tumor, and hormonal therapy has been proposed as a strategy for the treatment of HCC. The aim of the study is to investigate the effect of megestrol acetate, a synthetic progesteronal agent, on growth of HepG2 cells in vitro and in vivo.

EXPERIMENTAL DESIGN

Cell growth in vitro was assessed by a colormetric method, and cell growth in vivo was assessed by tumor volumetrics.

RESULTS

Megestrol acetate was shown to inhibit the growth of HepG2 cells in vitro in dose- and time-dependent manners with an IC (50) of 260 microm (24-h incubation). The growth of HepG2 cell-transplanted tumors in nude mice was also inhibited by i.p. injection of megestrol acetate (10 mg/kg/day). The tumor volumes of the megestrol acetate-treated group regressed to 59% of controls by week 6 and to 41% of controls by week 13. Apoptosis following G(1) arrest was observed in megestrol acetate-treated cells and may be a mechanism through which megestrol acetate inhibits HepG2 cells. Megestrol acetate was also demonstrated to have a beneficial effect on the weight gain of tumor-bearing nude mice, and the mean weight of the megestrol acetate-treated animals was higher than that of controls from week 4 of the treatment period, and the differences were statistically significant in week 5 and 6 (P < 0.05, compared with controls). No significant survival advantage was, however, demonstrated in the treatment group.

CONCLUSIONS

This study showed that megestrol acetate inhibited the growth of HepG2 cells grown in vitro and in vivo. These data provide useful information for clinical study of megestrol acetate for the treatment of HCC.

Treatment of recurrent or metastatic renal cell carcinoma

The management of recurrent renal cell carcinoma is challenging as it requires close collaboration between surgeons, radiation oncologists and medical oncologists. To date, treatment options for metastatic disease have been of modest benefit. The disease has therefore been a good model for novel drug development programs. These endeavors are now bearing fruit with exciting preliminary data now emerging in relation to a number of novel agents.

Randomized, placebo-controlled, phase III surgical adjuvant clinical trial of megestrol acetate (Megace) in selected patients with malignant melanoma

A randomized, double-blind, placebo-controlled phase III clinical trial was performed to assess megestrol acetate (Megace) as a postsurgical adjuvant therapy for patients with locally advanced malignant melanoma. Patients whose tumors were greater than 1.7 mm thick and had no regional lymph node involvement and patients with regional lymph node involvement were randomized to receive either 160 mg twice per day oral suspension of megestrol acetate or placebo. Treatment was administered for a maximum of 2 years or until disease progression. The study accrued 262 eligible patients. All but two patients were followed until death or a minimum of 4.5 years. Disease progression was documented in 156 patients. Neither progression-free survival (PFS) nor overall survival (OS) was found to differ between the treatments. The median PFS was 2.4 years in the megestrol acetate arm and 2.3 years in the placebo arm. Multivariate analysis revealed a significantly decreased PFS for patients with four or more positive regional lymph nodes and metachronous nodal disease. Median OS was 5.3 years in the megestrol acetate arm and 3.9 years in the placebo arm. Multivariate analysis revealed that OS was significantly decreased for patients 70 years of age or older with four or more positive lymph nodes. Adjuvant therapy with megestrol acetate oral suspension administered at a dose of 160 mg twice a day for 2 years was not found to be effective in prolonging PFS or OS in patients with surgically resected, locally advanced melanoma.

Dose-response trial of megestrol acetate in advanced breast cancer: cancer and leukemia group B phase III study 8741

PURPOSE

To investigate whether dose escalation of megestrol acetate (MA) improves response rate and survival in comparison with standard doses of MA.

PATIENTS AND METHODS

Three hundred sixty-eight patients with metastatic breast cancer, positive and/or unknown estrogen and progesterone receptors, zero or one prior trial of hormonal therapy, and no prior chemotherapy for metastatic disease were prospectively randomized into three groups. The groups of patients received either MA 160 mg/d (one tablet per day), MA 800 mg/d (five tablets per day), or MA 1,600 mg/d (10 tablets per day).

RESULTS

Patient characteristics were well balanced in the three treatment groups. Three hundred sixty-six patients received treatment and were included in the analyses. The response rates were 23%, 27%, and 27% for the 160-mg, 800-mg, and 1,600-mg arms, respectively. Response duration correlated inversely with dose. Median durations of response were 17 months, 14 months, and 8 months for the 160-mg, 800-mg, and 1,600-mg arms, respectively. No significant differences in the treatment arms were noted for time to disease progression or for survival; survival medians were 28 months (low dose), 24 months (mid dose) and 29 months (high dose). The most frequent and troublesome toxicity, weight gain, was dose-related, with approximately 20% of patients on the two higher-dose arms reporting weight gain of more than 20% of their prestudy weight, compared with only 2% in the 160-mg dose arm.

CONCLUSION

With a median follow-up of 8 years, these results demonstrate no advantage for dose escalation of MA in the treatment of metastatic breast cancer.

Improved quality of life with megestrol acetate in patients with endocrine-insensitive advanced cancer: a randomised placebo-controlled trial. Australasian Megestrol Acetate Cooperative Study Group

PURPOSE

To investigate the effect of two doses of megestrol acetate (MA) compared with placebo on quality of life (QoL) and nutritional status (NS) in patients with advanced endocrine-insensitive cancer.

PATIENTS AND METHODS

Two hundred forty patients were randomised to double-blind MA 480 mg/day, MA 160 mg/day, or matching placebo for 12 weeks. Nutritional status (including weight, skinfold thickness and midarm circumference) and QoL (using 6 linear analogue self-assessment (LASA) scales) were assessed at randomisation and after four, eight and 12 weeks. A QoL ranking incorporating QoL and death was also used ranging from 1 = dead to 5 = much better QoL.

RESULTS

One hundred seventy-four patients were assessable at week four, 136 at week eight and 103 patients at week 12. Patients receiving MA reported substantially better appetite (P = 0.001), mood (P = 0.001) and overall quality of life (P < 0.001), and possibly less nausea and vomiting (P = 0.08) than patients receiving placebo, based on a test for trend. A larger benefit was seen with the higher dose which (unlike the lower dose) was significantly better in pairwise comparisons with placebo for appetite, mood and overall QoL (each P < or = 0.001). Despite some missing data on QoL scores, QoL ranking was available on 227 (95%) of patients with significantly higher QoL ranking associated with MA (P = 0.002). Improvements in QoL occurred early within four weeks and were sustained. No statistically significant differences were observed in NS measurements, including weight (P = 0.29). Side effects of therapy were minor and did not differ significantly across treatments.

CONCLUSION

Megestrol acetate given at 480 mg/day is useful palliation in patients with endocrine-insensitive advanced cancer. It improves appetite, mood and overall quality of life in these patients, although not through a direct effect on nutritional status.

Uterine adenocarcinoma metastatic to the skin responsive to megestrol acetate

BACKGROUND

Although endometrial carcinoma is the most common gynecological cancer, it only rarely metastasizes to the skin, with a reported prevalence of 0.8%. We report a case of an elderly lady who recently developed cutaneous metastases from an endometrial primary diagnosed 7 years earlier.

OBJECTIVE

Our purpose was to determine if the oral administration of megestrol acetate would be effective in the treatment of uterine adenocarcinoma metastatic to the skin.

METHODS

The index case was given oral megestrol acetate over a period of 9 months. Pre- and posttreatment skin biopsies were performed and analyzed.

RESULTS

During treatment with megestrol acetate, the cutaneous metastases in the abdominal skin decreased in area to less than 10% of the pretreatment surface area correlating with a marked histopathologic decrease in adenocarcinomatous glandular structures.

CONCLUSION

Megestrol acetate can be successfully utilized in the treatment of endometrial adenocarcinoma metastatic to the skin as well as ostensibly in the treatment of other progesterone-sensitive metastatic cutaneous carcinomas.

Malnutrition in AIDS

Malnutrition, weight loss, and chronic diarrhea are common findings in patients infected with human immunodeficiency virus (HIV), and many traditional and nontraditional dietary approaches have been suggested. This article examines the mechanisms and pathophysiology of wasting in HIV, and the evidence for malnutrition of protein, energy, and micronutrients in patients with the acquired immunodeficiency syndrome (AIDS). The article concludes with a review of dietary therapy in AIDS patients.

The effect of danazol on tumour control and weight loss in patients on tamoxifen therapy for advanced breast cancer: a randomised double-blind placebo controlled trial

To assess the effect of danazol in advanced breast cancer 183 patients were randomised to receive either tamoxifen plus danazol or tamoxifen plus placebo. Patients underwent systemic work-up pretreatment then every 12 weeks or sooner if they clinically progressed. There were no differences in objective response rates with tamoxifen plus danazol vs. tamoxifen plus placebo (27% vs. 24%), time to progression (median 6.4 vs. 6.2 months) or survival (median 22.6 vs. 23.5 months) when the two arms were compared (all P > 0.5). The addition of danazol to tamoxifen had no effect on time to progression when adjusted for significant prognostic factors in a multivariate analysis. However, it was found incidentally that weight was stable on tamoxifen plus danazol (average gain 0.6 kg, S.E. 0.6 kg) compared with a significant loss on tamoxifen plus placebo (average loss 2.0 kg, S.E. 0.6 kg, P = 0.003). The average weight was maintained on tamoxifen plus danazol even in patients who did not respond to treatment.

The microepidemiology of wasting syndrome, a common link to diarrheal disease, cancer, rabies, animal models of AIDS, and HIV-AIDS YHAIDS). The feline leukemia virus and rabies virus models

Infant cats were inoculated intracranially with rabies or feline leukemia viruses in an experimental study of wasting syndrome. The daily pre- and postinoculation body weights were recorded until kittens were moribund. Affected animals in both groups manifested growth failure or wasting syndrome. Immunodepression, manifested by a conspicuous depletion of thymic cortex, the thymus dependent areas of the spleen, and growth hormone producing-alpha adenopituicytes was significantly (p less than 0.01) related to the wasting status of the animals. The ability of pituitary glands from these animals to produce growth hormone was studied by in situ immunoperoxidase staining and showed a significant (p less than 0.01) difference between healthy and wasted animals. Rabies and feline leukemia viruses were each found responsible for the low immunoreactivity of growth hormone producing alpha adenopituicytes. Because the hypothalamus and the hypophysis were both found infected, it was concluded that regardless of the triggering agent in primary wasting, the hypothalamic-hypophyseal-thymic axis was always involved through a decrease in growth hormone production.