Clinical and toxicity predictors of response and progression to temsirolimus in women with recurrent or metastatic endometrial cancer

Small-Molecule Inhibitors (SMIs) as an Effective Therapeutic Strategy for Endometrial Cancer

Endometrial cancer (EC) is the sixth most common cancer in women. A continued number of low-risk EC patients at diagnosis, as well as patients diagnosed with advanced-stage disease, will experience an aggressive disease. Unfortunately, those patients will present recurrence or overt dissemination. Systemic cytotoxic chemotherapy treatment on advanced, recurrent, or metastatic EC patients has shown poor results, with median survival rates of less than one year, and median progression-free survival rates of four months. Therefore, the search for innovative and alternative drugs or the development of combinatorial therapies involving new targeted drugs and standard regimens is imperative. Over the last few decades, some small-molecule inhibitors have been introduced in the clinics for cancer treatment, but only a few have been approved by the Food and Drug Administration (FDA) for EC treatment. In the present review, we present the current state and future prospects of small-molecule inhibitors on EC treatment, both alone and in combination.

Oral stomatitis and mTOR inhibitors: A review of current evidence in 20,915 patients

BACKGROUND

Traditional treatment of malignancies with chemotherapeutic agents is often affected by the damage inflicted on non-cancerous cells. Toxicities of the oral cavity, such as mucositis and stomatitis, are some of the most significant and unavoidable toxicities associated with anti-cancer therapies. For such reason, in the last decades, newer targeted agents have been developed aiming to decrease the rates of side effects on healthy cells. Unfortunately, targeted anti-cancer therapies also showed significant rate of toxicity on healthy tissues. mTOR inhibitors showed some adverse events, such as hyperglycemia, hyperlipidemia, hypophosphatemia, hematologic toxicities, and mucocutaneous eruption, but the most important are still stomatitis and skin rash, often reported as dose-limiting side effects.

PATIENTS AND METHODS

A search of the literature was performed by authors on the PubMed online database using the following key words: "sirolimus" OR "everolimus" OR "temsirolimus" OR "deforolimus" OR "ridaforolimus" combined with the Boolean operator AND with the terms: "stomatitis" OR "mucositis" OR "oral pain." Titles and abstracts of 382 potentially relevant studies were screened; of these, 114 studies were excluded because they did not report the inclusion criteria. In the second round, 268 studies were read full-text, but only 135 reported the inclusion criteria and were included for data extraction. Of the included studies, 95 referred to everolimus use, 16 to ridaforolimus, and 26 to temsirolimus (two studies referred to both everolimus and temsirolimus).

RESULTS

The incidence rate of stomatitis according to the agent used was 25.07% (3,959/15,787) for everolimus, 27.02% (724/2,679) for temsirolimus, and 54.76% (598/1,092) for ridaforolimus. All the three agents analyzed showed high rates of low-grade stomatitis (G1-G2), while the onset of severe stomatitis (G3-G4) was rare.

CONCLUSIONS

Analysis of the reports with patients treated with everolimus, temsirolimus, and ridaforolimus showed a clear prevalence of stomatitis grade 1 or 2. These data differ from that of patients treated with conventional chemotherapy in which mucositis is predominantly of grade 3 or 4.

mTOR signalling: jack-of-all-trades 1

The mechanistic target of rapamycin (mTOR) is an evolutionarily conserved serine/threonine kinase that senses and integrates environmental information into cellular regulation and homeostasis. Accumulating evidence has suggested a master role of mTOR signalling in many fundamental aspects of cell biology and organismal development. mTOR deregulation is implicated in a broad range of pathological conditions, including diabetes, cancer, neurodegenerative diseases, myopathies, inflammatory, infectious, and autoimmune conditions. Here, we review recent advances in our knowledge of mTOR signalling in mammalian physiology. We also discuss the impact of mTOR alteration in human diseases and how targeting mTOR function can treat human diseases.

Temsirolimus in women with platinum-refractory/resistant ovarian cancer or advanced/recurrent endometrial carcinoma. A phase II study of the AGO-study group (AGO-GYN8)

OBJECTIVES

To evaluate activity and toxicity of mTOR inhibitor temsirolimus in patients with platinum-refractory/resistant ovarian cancer (OC) or advanced/recurrent endometrial carcinoma (EC).

METHODS

Women with epithelial ovarian, fallopian tube or primary peritoneal cancer were eligible, when they had progression during treatment with a platinum based regimen or within 6 months after receiving a platinum based regimen and a previous taxane treatment. Women with advanced/recurrent EC, no longer amenable to curative surgery and/or radiotherapy were eligible when they had no previous or only adjuvant chemotherapy. Preceding endocrine therapy for metastatic/recurrent disease was allowed. Patients received weekly IV infusions of 25mg temsirolimus. Primary endpoint was progression free survival rate after 4 months (OC) or 6 months (EC). A two stage design was applied.

RESULTS

Forty-four patients (OC: n=22; EC: n=22) were enrolled and received temsirolimus treatment. Median age was 56 years (OC) or 63 years (EC). After eight weeks of treatment, 10 of 21 evaluable patients in the OC cohort and 8 of 20 evaluable patients in the EC cohort had progressive disease. Thus efficacy did not meet the predefined levels during the first stage of recruitment and the trial was stopped. Some patients in both cohorts had long lasting PFS (>7 months). Toxicity of temsirolimus was mild.

CONCLUSIONS

Temsirolimus treatment was well tolerated in our patients, but did not meet the predefined efficacy criteria. In our study as in other trials on rapalogs in OC or EC, a few patients had long lasting disease stabilisations.

Emerging drugs for endometrial cancer

INTRODUCTION

From the dualistic classification that divides endometrial cancer (EC) into two types with distinct underlying molecular profiling, histopathology and clinical behavior, arises a deeper understanding of the carcinogenesis pathways. EC treatment comprises different and multimodal therapeutic approaches, such as chemotherapy, radiation therapy or combinations of novel drugs; however, few of these regimens have truly improved progression-free or survival rates in advanced and metastatic settings.

AREAS COVERED

We reviewed the main molecular pathways involved in EC carcinogenesis through a wide literature search of novel compounds that alone or in combination with traditional drugs have been investigated or are currently under investigation in randomized clinical trials.

EXPERT OPINION

The molecular therapies mainly discussed in this review are potential therapeutic candidates for more effective and specific treatments. In the genomic era, a deeper knowledge about molecular characteristics of cancer provides the hope for the development of better therapeutic approaches. Targeting both genetic and epigenetic alterations, attacking tumor cells using cell-surface markers overexpressed in tumor tissue, reactivating antitumor immune responses and identifying predictive biomarkers represent the emerging strategies and the major challenges.