Etoposide, vincristine, doxorubicin and dexamethasone (EVAD) combination chemotherapy as second-line treatment for advanced AIDS-related Kaposi's sarcoma

Targeting steroid hormone receptors for anti-cancer therapy-A review on small molecules and nanotherapeutic approaches

The steroid hormone receptors (SHRs) among nuclear hormone receptors (NHRs) are steroid ligand-dependent transcription factors that play important roles in the regulation of transcription of genes promoted via hormone responsive elements in our genome. Aberrant expression patterns and context-specific regulation of these receptors in cancer, have been routinely reported by multiple research groups. These gave an window of opportunity to target those receptors in the context of developing novel, targeted anticancer therapeutics. Besides the development of a plethora of SHR-targeting synthetic ligands and the availability of their natural, hormonal ligands, development of many SHR-targeted, anticancer nano-delivery systems and theranostics, especially based on small molecules, have been reported. It is intriguing to realize that these cytoplasmic receptors have become a hot target for cancer selective delivery. This is in spite of the fact that these receptors do not fall in the category of conventional, targetable cell surface bound or transmembrane receptors that enjoy over-expression status. Glucocorticoid receptor (GR) is one such exciting SHR that in spite of it being expressed ubiquitously in all cells, we discovered it to behave differently in cancer cells, thus making it a truly druggable target for treating cancer. This review selectively accumulates the knowledge generated in the field of SHR-targeting as a major focus for cancer treatment with various anticancer small molecules and nanotherapeutics on progesterone receptor, mineralocorticoid receptor, and androgen receptor while selectively emphasizing on GR and estrogen receptor. This review also briefly highlights lipid-modification strategy to convert ligands into SHR-targeted cancer nanotherapeutics. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Biology-Inspired Nanomaterials > Lipid-Based Structures Therapeutic Approaches and Drug Discovery > Emerging Technologies.

A patent review of anticancer glucocorticoid receptor modulators (2014-present)

Introduction: Natural and synthetic glucocorticoids are widely employed in different diseases, among which are hematological and solid tumors. Their use is however associated with a number of serious side effects and by the occurrence of resistance. With the aim of separating their gene transactivating effect, more linked to side effects, from transrepressive properties, associated with therapeutic efficacy, a number of selective glucocorticoid modulators have been identified.Areas covered: This review summarizes the patent applications from 2014 to present in the field of selective glucocorticoid receptor modulators employed in cancer therapy. Only few patents have been identified, that concern the identification of new molecules or the method of use of already patented compounds. In addition, a discussion of the mechanism of action of these compounds is included.Expert opinion: Only a very limited number of patents have been applied that concern selective glucocorticoid receptor modulators and their use in cancer. Biological information is scarce for most of these patents; more research is necessary in this field in particular concerning clinical data in order to understand whether it is actually possible to improve the efficacy and therapeutic index of these compounds in cancer therapy.

Glucocorticoids and Cancer

Unlike other steroid hormone receptors, the glucocorticoid receptor (GR) is not considered an oncogene. In breast cancer, the estrogen receptor (ER) drives cell growth, proliferation, and metastasis, and the androgen receptor (AR) plays a similar role in prostate cancer. Accordingly, treatment of these diseases has focused on blocking steroid hormone receptor function. In contrast, glucocorticoids (GCs) work through GR to arrest growth and induce apoptosis in lymphoid tissue. Glucocorticoids are amazingly effective in this role, and have been deployed as the cornerstone of lymphoid cancer treatment for decades. Unfortunately, not all patients respond to GCs and dosage is restricted by immediate and long term side effects. In this chapter we review the treatment protocols that employ glucocorticoids as a curative agent, elaborate on what is known about their mechanism of action in these cancers, and also summarize the palliative uses of glucocorticoids for other cancers.

Treatment of severe or progressive Kaposi's sarcoma in HIV-infected adults

BACKGROUND

Kaposi's sarcoma remains the most common cancer in Sub-Saharan Africa and the second most common cancer in HIV-infected patients worldwide. Since the introduction of highly active antiretroviral therapy (HAART), there has been a decline in its incidence.However, Kaposi's sarcoma continues to be diagnosed in HIV-infected patients.

OBJECTIVES

To assess the added advantage of chemotherapy plus HAART compared to HAART alone; and the advantages of different chemotherapy regimens in HAART and HAART naive HIV infected adults with severe or progressive Kaposi's sarcoma.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and , GATEWAY, the WHO Clinical Trials Registry Platform and the US National Institutes of Health's ClinicalTrials.gov for ongoing trials and the Aegis archive of HIV/AIDS for conference abstracts. An updated search was conducted in July 2014.

SELECTION CRITERIA

Randomised trials and observational studies evaluating the effects of any chemotherapeutic regimen in combination with HAART compared to HAART alone, chemotherapy versus HAART, and comparisons between different chemotherapy regimens.

DATA COLLECTION AND ANALYSIS

Two review authors assessed the studies independently and extracted outcome data.We used the risk ratio (RR) with a 95% confidence interval (CI) as the measure of effect.We did not conduct meta-analysis as none of the included trials assessed identical chemotherapy regimens.

MAIN RESULTS

We included six randomised trials and three observational studies involving 792 HIV-infected adults with severe Kaposi's sarcoma.Seven studies included patients with a mix of mild to moderate (T0) and severe (T1) Kaposi's sarcoma. However, this review was restricted to the subset of participants with severe Kaposi's sarcoma disease.Studies comparing HAART plus chemotherapy to HAART alone showed the following: one trial comparing HAART plus doxorubicin,bleomycin and vincristine (ABV) to HAART alone showed a significant reduction in disease progression in the HAART plus ABV group (RR 0.10; 95% CI 0.01 to 0.75, 100 participants); there was no statistically significant reduction in mortality and no difference in adverse events. A cohort study comparing liposomal anthracyclines plus HAART to HAART alone showed a non-statistically significant reduction in Kaposi's sarcoma immune reconstitution inflammatory syndrome in patients that received HAART plus liposomal anthracyclines (RR 0.49; 95% CI 0.16 to 1.55, 129 participants).Studies comparing HAART plus chemotherapy to HAART plus a different chemotherapy regimen showed the following: one trial involving 49 participants and comparing paclitaxel versus pegylated liposomal doxorubicin in patients on HAART showed no difference in disease progression. Another trial involving 46 patients and comparing pegylated liposomal doxorubicin versus liposomal daunorubicin showed no participants with progressive Kaposi's sarcoma disease in either group.Studies comparing different chemotherapy regimens in patients from the pre-HAART era showed the following: in the single RCT comparing liposomal daunorubicin to ABV, there was no significant difference with the use of liposomal daunorubicin compared to ABV in disease progression (RR 0.78; 95% CI 0.34 to 1.82, 227 participants) and overall response rate. Another trial involving 178 participants and comparing oral etoposide versus ABV demonstrated no difference in mortality in either group. A non-randomised trial comparing bleomycin alone to ABV demonstrated a higher median survival time in the ABV group; there was also a non-statistically significant reduction in adverse events and disease progression in the ABV group (RR 11; 95% CI 0.67 to 179.29, 24 participants).An additional non-randomised study showed a non-statistically significant overall mortality benefit from liposomal doxorubicin as compared to conservative management consisting of either bleomycin plus vinblastine, vincristine or single-agent antiretroviral therapy alone (RR 0.93; 95% CI 0.75 to 1.15, 29 participants). The overall quality of evidence can be described as moderate quality. The quality of evidence was downgraded due to the small size of many of the included studies and small number of events.

AUTHORS' CONCLUSIONS

The findings from this review suggest that HAART plus chemotherapy may be beneficial in reducing disease progression compared to HAART alone in patients with severe or progressive Kaposi's sarcoma. For patients on HAART, when choosing from different chemotherapy regimens, there was no observed difference between liposomal doxorubicin, liposomal daunorubicin and paclitaxel.

In vitro efficacy of doxorubicin and etoposide against a feline injection site sarcoma cell line

Feline injection site sarcoma (ISS) is a locally invasive tumor, in which surgical treatment is frequently combined with radiation or chemotherapy to improve tumor control. The focus of this study was to evaluate the cytotoxic effects of doxorubicin or etoposide on a feline injection site sarcoma cell line (JB) and to assess the impact of combining these drugs on cell death and cell cycle. Both single agent and combination drug administration increased cell death and significantly reduced the number of viable cells. Cells in G0/G1 were significantly reduced while the G2/M fraction was significantly increased following treatment. Collectively, combining doxorubicin and etoposide at the lower EC yielded comparable results to the EC50 of either drug alone in degree of cytotoxicity, level of apoptosis, and % of cells in G2/M. The results of this study indicate that doxorubicin and etoposide alone and in combination differentially alter ISS cell viability and cycle.