Role of mTOR signaling in tumor microenvironment. An overview

The mammalian target of rapamycin (mTOR) pathway regulates major processes by integrating a variety of exogenous cues, including diverse environmental inputs in the tumor microenvironment (TME). In recent years, it has been well recognized that cancer cells co-exist and co-evolve with their TME, which is often involved in drug resistance. The mTOR pathway modulates the interactions between the stroma and the tumor, thereby affecting both the tumor immunity and angiogenesis. The activation of mTOR signaling is associated with these pro-oncogenic cellular processes, making mTOR a promising target for new combination therapies. This review highlights the role of mTOR signaling in the characterization and the activity of the TME’s elements and their implications in cancer immunotherapy

Randomised phase 3 open-label trial of first-line treatment with gemcitabine in association with docetaxel or paclitaxel in women with metastatic breast cancer: a comparison of different schedules and treatments

BACKGROUND: This open-label study compared docetaxel/gemcitabine vs. paclitaxel/gemcitabine and a weekly (W) vs. 3-weekly (3 W) schedule in metastatic breast cancer (MBC). METHODS: Patients relapsed after adjuvant/neoadjuvant anthracycline-containing chemotherapy were randomized to: A) gemcitabine 1000 mg/m(2) Day 1,8 + docetaxel 75 mg/m(2) Day 1 q3W; B) gemcitabine 1250 mg/m(2) Day 1,8 + paclitaxel 175 mg/m(2) Day 1 q3W; C) gemcitabine 800 mg/m(2) Day 1,8,15 + docetaxel 30 mg/m(2) Day 1,8,15 q4W; D) gemcitabine 800 mg/m(2) Day 1,15 + paclitaxel 80 mg/m(2) Day 1,8,15 q4W. Primary endpoint was time-to-progression (TTP). Secondary endpoints were overall survival (OS) and overall response rate (ORR). RESULTS: Interim analysis led to accrual interruption (241 patients enrolled of 360 planned). Median TTP (months) was 8.33 (95% CI: 6.19-10.16) with W and 7.51 (95% CI: 5.93-8.33) with 3 W (p=0.319). No differences were observed in median TTP between docetaxel and paclitaxel, with 85.6% and 87.0% of patients progressing, respectively. OS did not differ between regimens/schedules. ORR was comparable between regimens (HR: 0.882; 95% CI: 0.523-1.488; p=0.639), while it was significantly higher in W than in the 3 W (HR: 0.504; 95% CI: 0.299-0.850; p=0.010) schedule. Grade 3/4 toxicities occurred in 69.2% and 71.9% of patients on docetaxel and paclitaxel, and in 65.8% and 75.2% in W and 3 W. CONCLUSIONS: Both treatment regimens showed similar TTP. W might be associated with a better tumour response compared with 3 W. TRIAL REGISTRATION: Clinicaltrial.gov ID NCT0023689

Fluorouracil and dose-dense chemotherapy in adjuvant treatment of patients with early-stage breast cancer: An open-label, 2 × 2 factorial, randomised phase 3 trial

Background: Whether addition of fluorouracil to epirubicin, cyclophosphamide, and paclitaxel (EC-P) is favourable in adjuvant treatment of patients with node-positive breast cancer is controversial, as is the benefit of increased density of dosing. We aimed to address these questions in terms of improvements in disease-free survival. METHODS: In this 2 × 2 factorial, open-label, phase 3 trial, we enrolled patients aged 18-70 years with operable, node positive, early-stage breast cancer from 81 Italian centres. Eligible patients were randomly allocated in a 1:1:1:1 ratio with a centralised, interactive online system to receive either dose-dense chemotherapy (administered intravenously every 2 weeks with pegfilgrastim support) with fluorouracil plus EC-P (FEC-P) or EC-P or to receive standard-interval chemotherapy (administered intravenously every 3 weeks) with FEC-P or EC-P. The primary study endpoint was disease-free survival, assessed with the Kaplan-Meier method in the intention-to-treat population. Our primary comparisons were between dose schedule (every 2 weeks vs every 3 weeks) and dose type (FEC-P vs EC-P). This study is registered with ClinicalTrials.gov, number NCT00433420. FINDINGS: Between April 24, 2003, and July 3, 2006, we recruited 2091 patients. 88 patients were enrolled in centres that only provided standard-intensity dosing. After a median follow-up of 7·0 years (interquartile range [IQR] 4·5-6·3), 140 (26%) of 545 patients given EC-P every 3 weeks, 157 (29%) of 544 patients given FEC-P every 3 weeks, 111 (22%) of 502 patients given EC-P every 2 weeks, and 113 (23%) of 500 patients given FEC-P every 2 weeks had a disease-free survival event. For the dose-density comparison, disease-free survival at 5 years was 81% (95% CI 79-84) in patients treated every 2 weeks and 76% (74-79) in patients treated every 3 weeks (HR 0·77, 95% CI 0·65-0·92; p=0·004); overall survival rates at 5 years were 94% (93-96) and 89% (87-91; HR 0·65, 0·51-0·84; p=0·001) and for the chemotherapy-type comparison, disease-free survival at 5 years was 78% (75-81) in the FEC-P groups and 79% (76-82) in the EC-P groups (HR 1·06, 0·89-1·25; p=0·561); overall survival rates at 5 years were 91% (89-93) and 92% (90-94; 1·16, 0·91-1·46; p=0·234). Compared with 3 week dosing, chemotherapy every 2 weeks was associated with increased rate of grade 3-4 of anaemia (14 [1·4%] of 988 patients vs two [0·2%] of 984 patients; p=0·002); transaminitis (19 [1·9%] vs four [0·4%]; p=0·001), and myalgias (31 [3·1%] vs 16 [1·6%]; p=0·019), and decreased rates of grade 3-4 neutropenia (147 [14·9%] vs 433 [44·0%]; p<0·0001). Addition of fluorouracil led to increased rates of grade 3-4 neutropenia (354 [34·5%] of 1025 patients on FEC-P vs 250 [24·2%] of 1032 patients on EC-P; p<0·0001), fever (nine [0·9%] vs two [0·2%]), nausea (47 [4·6%] vs 28 [2·7%]), and vomiting (32 [3·1%] vs 15 [1·4%]). INTERPRETATION: In patients with node-positive early breast cancer, dose-dense adjuvant chemotherapy improved disease-free survival compared with standard interval chemotherapy. Addition of fluorouracil to a sequential EC-P regimen was not associated with an improved disease-free survival outcome

Clinical utility of continuing trastuzumab beyond brain progression in HER-2 positive metastatic breast cancer

No abstract availabl

The withdrawal from oncogenetic counselling and testing for hereditary and familial breast and ovarian cancer. A descriptive study of an Italian sample

<p>Abstract</p> <p>Background</p> <p>Oncogenetic counselling is seldom followed through, even when individuals are eligible according to the test criteria. The basic variables which influence the decision to undergo the genetic counselling process are: risk perception, expected benefit or limitations of genetic testing, general psychological distress or cancer-specific distress, lack of trust in one's emotional reactions when faced with negative events, expected level of family support and communications within the family. The aim of this study was to describe the psychosocial variables of an Italian sample that forgoes genetic counselling.</p> <p>Methods</p> <p>From May 2002 to December 2006 a psychological questionnaire was sent out to one hundred and six subjects, who freely requested a first genetic informative consultation, and never asked to have a second visit and the family tree drawn up in order to inquire about their eligibility for genetic testing. Statistical analysis was performed by Pearson chi-square test, t-test and Spearman RHO coefficient.</p> <p>Results</p> <p>The survey presents a lack of emotional cohesion and structured roles and rules within the family system and a positive correlation between the number of children, anxiety and risk perception. The main reasons for giving up on counselling were a sense that testing was a waste of time and the inability to emotionally handle the negative consequences of the test outcome. The subjects who maintained that test and an early diagnosis were a "waste of time" experienced more anxiety.</p> <p>Conclusion</p> <p>The study revealed the importance to ac knowledging the whole persona and their family system as well as provide information highlighting usefulness of early diagnosis.</p

PET scanning evaluation of response to imatinib mesylate therapy in gastrointestinal stromal tumor (GIST) patients

Background: Unresectable or metastatic gastrointestinal stromal tumors (GISTs) exhibit a dynamic clinical course, with no evidence of benefit from any standard cytotoxic chemotherapy and an inevitably fatal outcome. With the introduction of Imatinib, an oral drug able to inhibit the KIT receptor tyrosine kinase, new questions arise regarding our ability to monitor treatment response with conventional methods and optimally manage such patients on treatment with new agents. Materials and methods: Herein we report two cases of patients with a history of GIST in treatment with Imatinib. Results: After 4 weeks from treatment start, CT scan evaluation demonstrated a massive increase in the size of metastatic lesions, but a confirmatory PET excluded, in both patients, the presence of any metabolic activity in the previously known metastatic sites. Imatinib therapy was continued with subjective clinical benefit for 12 further months before a PET scan-confirmed disease progression had occurred in one patient and is still ongoing after 15 months in the other. Conclusion: These cases open the obvious question of whether conventional imaging techniques are adequate to assess the response to Imatinib treatment in GIST patients

Efficacy and safety of T-DM1 in the 'common-practice' of HER2+ advanced breast cancer setting: a multicenter study

Ado-trastuzumab emtansine (T-DM1) is an antibody-drug conjugate approved for the treatment of patients with human epidermal growth factor receptor 2 (HER2)-positive, metastatic breast cancer (mBC). The aim of this 'field-practice' study was to investigate the efficacy and safety of T-DM1, focusing on treatment line, previous lapatinib treatment and patterns of metastasis. Three hundred and three patients with HER2-positive mBC who received T-DM1 were identified by reviewing the medical records of 24 Italian Institutions. One hundred fourty-nine (49%) and 264 (87%) had received prior hormonal treatment and/or anti-HER2 targeted therapy, respectively. Particularly, 149 patients had been previously treated with lapatinib. The objective response rate (ORR) was 36.2%, and 44.5% when T-DM1 was administrated as second-line therapy. Considering only patients with liver metastases, the ORR was 44.4%. The median progression-free survival (PFS) was 7.0 months in the overall population, but it reached 9.0 and 12.0 months when TDM-1 was administered as second- and third-line treatment, respectively.In conclusion, in this 'real-word' study evaluating the effects of T-DM1 in patients with HER2-positive mBC who progressed on prior anti-HER2 therapies, we observed a clinically-relevant benefit in those who had received T-DM1 in early metastatic treatment-line and in subjects previously treated with lapatini

Antiangiogenic potential of the Mammalian target of rapamycin inhibitor temsirolimus

: Mammalian target of rapamycin (mTOR) is increasingly recognized as a master regulator of fundamental cellular functions, whose deregulation may underlie neoplastic transformation and progression. Hence, mTOR has recently emerged as a promising target for therapeutic anticancer interventions in several human tumors, including breast cancer. Here, we investigated the antiangiogenic potential of temsirolimus (also known as CCI-779), a novel mTOR inhibitor currently in clinical development for the treatment of breast cancer and other solid tumors. Consistent with previous reports, sensitivity to temsirolimus-mediated growth inhibition varied widely among different breast cancer cell lines and was primarily due to inhibition of proliferation with little, if any, effect on apoptosis induction. In the HER-2 gene-amplified breast cancer cell line BT474, temsirolimus inhibited vascular endothelial growth factor (VEGF) production in vitro under both normoxic and hypoxic conditions through inhibition of hypoxia-stimulated hypoxia-inducible factor (HIF)-1alpha expression and transcriptional activation. Interestingly, these effects were also observed in the MDA-MB-231 cell line, independent of its inherent sensitivity to the growth-inhibitory effects of temsirolimus. A central role for mTOR (and the critical regulator of cap-dependent protein translation, eIF4E) in the regulation of VEGF production by BT474 cells was further confirmed using a small interfering RNA approach to silence mTOR and eIF4E protein expression. In addition to its effect on HIF-1alpha-mediated VEGF production, temsirolimus also directly inhibited serum- and/or VEGF-driven endothelial cell proliferation and morphogenesis in vitro and vessel formation in a Matrigel assay in vivo. Overall, these results suggest that antiangiogenic effects may substantially contribute to the antitumor activity observed with temsirolimus in breast cancer