Systematic Review and Meta-Analysis of the Influence of Genetic Variation on Ototoxicity in Platinum-Based Chemotherapy

OBJECTIVE

The objective of this meta-analysis is to evaluate the impact of genetic polymorphisms on platinum-based chemotherapy (PBC)-induced ototoxicity.

DATA SOURCES

Systematic searches of PubMed, Embase, Cochrane, and Web of Science were conducted from the inception of the databases to May 31, 2022. Abstracts and presentations from conferences were also reviewed.

REVIEW METHODS

Four investigators independently extracted data in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Differences in the prevalence of PBC-induced ototoxicity between reference and variant (i) genotypes and (ii) alleles were analyzed. The overall effect size was presented using the random-effects model as an odds ratio (OR) with a 95% confidence interval (CI).

RESULTS

From 32 included articles, 59 single nucleotide polymorphisms on 28 genes were identified, with 4406 total unique participants. For allele frequency analysis, the A allele in ACYP2 rs1872328 was positively associated with ototoxicity (OR: 2.61; 95% CI: 1.06-6.43; n = 2518). Upon limiting to cisplatin use only, the T allele of COMT rs4646316 and COMT rs9332377 revealed significant results. For genotype frequency analysis, the CT/TT genotype in ERCC2 rs1799793 demonstrated an otoprotective effect (OR: 0.50; 95% CI: 0.27-0.94; n = 176). Excluding studies using carboplatin or concomitant radiotherapy revealed significant effects with COMT rs4646316, GSTP1 rs1965, and XPC rs2228001. Major sources of variations between studies include differences in patient demographics, ototoxicity grading systems, and treatment protocols.

CONCLUSION

Our meta-analysis presents polymorphisms that exert ototoxic or otoprotective effects in patients undergoing PBC. Importantly, several of these alleles are observed at high frequencies globally, highlighting the potential for polygenic screening and cumulative risk evaluation for personalized care.

Clinical efficacy and molecular effects of lenvatinib (Len) and letrozole (Let) in hormone receptor-positive (HR+) metastatic breast cancer (MBC)

1019

Background: Preclinical studies show cross talk between RET and estrogen receptor, with at least additive treatment (Tx) effect of Len, a RET inhibitor, with Let. Our previous work concluded a recommended phase 2 dose (RP2D) of Len 14mg daily and Let 2.5mg daily (Lim, ASCO 2019). We present efficacy data from dose escalation and expansion cohorts. Methods: Safety, tolerability and efficacy data of MBC patients in both dose escalation (Len dose level 1 [DL]:20mg, DL -1:16mg and DL -2:14mg) and expansion (Len 14mg) cohort of this phase Ib/II study of combination Len+Let study was analysed. Patients were treated with single-agent Len for 2 weeks, followed by Len+Let until disease progression (PD). Serial tumor biopsies at baseline, after Len alone, 4 weeks post Len+Let, and upon PD, were sequenced for 440 genes with the ACTOnco+ platform. Results: A total of 33 pts (DL1 6pts, DL-1 6pts, DL-2 + expansion 21pts) with median 5 lines of prior Tx (range 0-11) were enrolled; 87.9%, 75.8%, and 75.8% had prior endocrine therapy (ET), ET+CDK4/6 inhibitor (i), and chemotherapy (CT) respectively. Objective response rate (ORR), disease control rate (DCR) ≥6 months (m), median duration of response (DOR), and percentage progression-free (PPF) at 12m were 33.3%, 45.5%, 11.5m (range 6.3-22.4), and 27.2% respectively. Among patients who previously progressed on CDK4/6i (n = 25), ORR, DCR ≥6m, median DOR, and PPF at 12m were 24.0%, 40.0%, 13.7m (range 6.3-18.2), and 12.0% respectively. Of note, 3/25 (12%) patients had durable response to Len+Let lasting ≥12m, despite having only modest PFS on ET+CDK4/6i (3, 7, and 12 months respectively). Most frequent all-grade toxicities (tox) were HTN (n = 15, G3:15), hypothyroidism (n = 20, G3:0) and fatigue (n = 13, G3:2), with no G4/5 tox. No new toxicity signals were observed compared to dose escalation phase. Pre-treatment tumor molecular profiling showed responders to be more likely to harbor NEFH, USH2A and PTCH1 mutations, while non-responders were more likely to carry PIK3R1, APC and PALB2 mutations. Sequencing of serial biopsies showed downregulation of BRD4, PTCH1, KIT, NTRK1 and CREBBP after Len treatment. Conclusions: Len+Let showed significant anti-tumor activity with meaningful duration of response, even in pts who failed prior CT or ET+CDK4/6i. The results support further investigation in randomized studies. Tumor profiling identified mutations associated with response and insights on molecular effects of lenvatinib. Clinical trial information: NCT02562118 .

A phase Ib/II trial of lenvatinib (len) and letrozole (let) incorporating pharmacodynamics studies in postmenopausal women with hormone receptor positive (HR+) locally advanced/metastatic breast cancer (LABC/MBC)

1045

Background: Endocrine blockade (EB) is standard of care for patients (pts) with HR+ LABC/MBC. RET over-expression (RET+) occurs in up to 75% of HR+ breast cancers and is a postulated mechanism of endocrine resistance. Preclinical studies show cross talk between RET and estrogen receptor, and at least additive treatment (Tx) effect of Len+EB. Methods: We performed a phase Ib trial (3+3 dose escalation) to study safety, tolerability, pharmacodynamics and efficacy of Len+Let. Both drugs were given as continuous daily dosing with 2 weeks (wks) of Len alone, followed by Len+Let for 12 wks then surgery (LABC), or till disease progression (PD) (MBC). Serial tumor biopsies (n = 15) were done at baseline, after Len alone, 4 wks post Len+Let, and at surgery [LABC] / upon PD [MBC]. Results: 16 pts were treated (4 LABC, 12 MBC); Among MBC pts, median lines of prior Tx was 3 (range 0-10); 84.6%, 66.7%, and 58.3% had prior EB, EB+CDK4/6 inhibitor (i), and chemotherapy (CT) respectively. At dose level (DL) 1, 2/4 pts had dose-limiting toxicities (DLT). There was no DLT at DL-1, but 6/6 pts needed dose reductions (DR), with 4/6 DR within 6 wks of Len+Let (3 G3 hypertension [HTN], 1 G3 wound pain), deeming DL-1 intolerable. At DL-2, 0/6 pts had DLT; this was declared recommended phase 2 dose (RP2D). Most frequent G3 toxicities (tox) were HTN (6/16), proteinuria (2/16) and palmar-plantar erythrodysesthesia (PPE) (2/16), with no G4/5 tox. Len+Let was active with 93.8% overall disease control rate (DCR) (50.0% partial response [PR], 43.8% stable disease [SD]). Among MBCts (8/12 had prior EB+CDK4/6i), DCR ≥12 wks was 91.7%; 1 pt had sustained PR for 48 wks and 1 ongoing PR at 40 wks. 9/16 pts had RET+ tumors on immunohistochemistry at baseline, and 66.7% showed down-regulation with Tx (RECIST: 4 PR, 2 SD). Conclusions: Len+Let showed significant anti-tumor activity, even in pts who failed prior CT or EB+CDK4/6i. RP2D of 14mg Len and 2.5mg Let is tolerated with efficacy; dose expansion is currently underway. Clinical trial information: NCT02562118. [Table: see text]

Tumor pathological and immunological changes in HER2+ metastatic breast cancer (MBC) following trastuzumab combined with expanded and activated autologous natural killer (NK) cell infusion

e12511

Background: A central mechanism for the anti-tumor activity of Trastuzumab, a HER2 monoclonal antibody, against HER2+ tumors is induction of antibody dependent cell cytotoxicity (ADCC) mediated by NK cells. We are conducting a first-in-human trial of Trastuzumab followed by infusion of expanded, activated autologous NK cells in refractory HER2+ MBC (ClinicalTrials.gov: NCT02030561) to test the hypothesis that NK cell infusions will augment Trastuzumab-mediated ADCC and increase immune cell infiltration in tumor. Pre- and post-infusion tumor biopsies were obtained in a subset of patients to determine degree of NK cell infiltration in tumor and histopathological and immunological effects after infusion. Methods: HER2+ MBC patients underwent apheresis to harvest NK cells for ex vivo expansion and activation. NK cells (107/kg), expressing high levels of the antibody receptor CD16, were infused 24 hours post-Trastuzumab. Histology analysis and immunohistochemistry with CD56, CD3, CD20 and cleaved caspase-3 to identify NK, T, B, and apoptotic cells respectively, was performed in pre- and post-infusion biopsies. Studies of CD4 and CD8 to further classify T cell infiltrates, and CD16 to assess NK cell functionality are underway. Results: Analysis of 7 paired tumor biopsies collected before and 7-14 days after NK cell infusion showed absolute increase in lymphocyte infiltration (mean cell count/5 HPF: 204 vs 265 in pre- vs post- biopsy, p = 0.109). Most infiltrating lymphocytes were CD3+ T cells (74.28±12.72% vs 80 ±10% in pre vs post) and CD56+ NK cell number in the immune infiltrate were increased post infusion (mean cell count/5 HPF: 4.57±3.46 vs 20.57±13.83 in pre vs post; p = 0.009). Increased tumor apoptosis was observed post NK cell infusion (mean apoptotic cell count/5 HPF: 3.14±2.48 vs 5.86±6.72 in pre vs post, p = 0.27). Conclusions: Histopathology analysis of tumors from HER2+ MBC patients demonstrated significant increase in NK and T cells in tumor following Trastuzumab and NK cell infusion, suggesting that this combination might also augment recruitment of T lymphocytes into tumor, further enhancing anti-tumor activity. Clinical trial information: NCT02030561.

First-in-human trial of the oral ataxia telangiectasia and Rad3-related (ATR) inhibitor BAY 1895344 in patients (pts) with advanced solid tumors

3007

Background: The ATR kinase is a key regulator of the DNA damage response (DDR) machinery, activated by DNA damage and replication stress. BAY 1895344 is a novel, potent, and selective ATR inhibitor with anti-tumor activity in preclinical models with DDR defects. Methods: Pts with advanced metastatic solid tumors resistant or refractory to standard treatment, with and without DDR defects, received BAY 1895344 BID, 3 days (d) on/4 d off continuously in 3-weekly cycles. Results: As of December 20, 2018, 18 pts with colorectal (4), breast (3), prostate (2), and ovarian (2) cancers were enrolled across 6 cohorts (5 mg, 10 mg, 20 mg, 40 mg, 60 mg, and 80 mg BID). Median prior lines of treatment was 5. No dose-limiting toxicities (DLTs) were reported in the 5-40 mg cohorts. 2/3 pts had DLTs in the 80 mg cohort (grade [G] 4 neutropenia, G4 neutropenia and G4 thrombocytopenia) and 2/7 had DLTs in the 60 mg cohort (G4 neutropenia, G2 fatigue). 40 mg BID 3 on/4 off was defined as the maximum tolerated dose. Most common treatment-emergent adverse events included anemia, neutropenia, nausea, and fatigue. Pharmacokinetics appeared dose proportional. Pharmacodynamic analyses showed modulation of pH2AX and/or pKAP1 in paired tumor biopsies at exposures associated with preclinical anti-tumor activity. In 13 pts with and without DDR defects treated at dose levels ≥40 mg BID, the objective response rate was 30.7%, including 2/2 pts at 40 mg (appendix and urothelial cancer), 1/8 pts at 60 mg (breast), and 1/3 pts at 80 mg (endometrial). All responders had ATM protein loss of expression and/or ATM mutation; median treatment duration was 347 d (range 293-364 d). A BRCA1-mutant, olaparib-resistant ovarian cancer pt (60 mg) had a CA125 response and stable disease >10 months. 41 additional pts have been enrolled in ongoing expansion cohorts in cancers with DDR defects (prostate, breast, gynecologic, colorectal) or ATM protein loss (all comers) with responses observed. Conclusions: The ATR inhibitor BAY 1895344 is tolerated at biologically active doses with anti-tumor activity against cancers with certain DDR defects, including ATM protein loss. Clinical trial information: NCT03188965.

'Lnc'-ing Wnt in female reproductive cancers: therapeutic potential of long non-coding RNAs in Wnt signalling

Recent discoveries in the non-coding genome have challenged the original central dogma of molecular biology, as non-coding RNAs and related processes have been found to be important in regulating gene expression. MicroRNAs and long non-coding RNAs (lncRNAs) are among those that have gained attention recently in human diseases, including cancer, with the involvement of many more non-coding RNAs (ncRNAs) waiting to be discovered. ncRNAs are a group of ribonucleic acids transcribed from regions of the human genome, which do not become translated into proteins, despite having essential roles in cellular physiology. Deregulation of ncRNA expression and function has been observed in cancer pathogenesis. Recently, the roles of a group of ncRNA known as lncRNA have gained attention in cancer, with increasing reports of their oncogenic involvement. Female reproductive cancers remain a leading cause of death in the female population, accounting for almost a third of all female cancer deaths in 2016. The Wnt signalling pathway is one of the most important oncogenic signalling pathways which is hyperactivated in cancers, including female reproductive cancers. The extension of ncRNA research into their mechanistic roles in human cancers has also led to novel reported roles of ncRNAs in the Wnt pathway and Wnt-mediated oncogenesis. This review aims to provide a critical summary of the respective roles and cellular functions of Wnt-associated lncRNAs in female reproductive cancers and explores the potential of circulating cell-free lncRNAs as diagnostic markers and lncRNAs as therapeutic targets.

LINKED ARTICLES

This article is part of a themed section on WNT Signalling: Mechanisms and Therapeutic Opportunities. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.24/issuetoc.

Triple negative breast cancer in Asia: An insider's view

While tremendous improvement has been made for the treatment of breast cancers, the treatment of triple negative breast cancer (TNBC) still remains a challenge due to its aggressive characteristics and limited treatment options. Most of the studies on TNBC were conducted in Western population and TNBC is reported to be more frequent in the African women. This review encapsulates the studies conducted on TNBC patients in Asian population and elucidates the similarities and differences between these two regions. The current treatment of TNBC includes surgery, radiotherapy and chemotherapy. In addition to the current chemotherapies, which mainly include cytotoxic agents, such as taxanes and anthracyclines, many clinical trials are investigating the potential use of other chemotherapy drugs, targeted therapeutics and combinational therapies to treat TNBC. Moreover, this review also integrates the studies involving novel markers, which will help us to dissect the pathologic process of TNBC and in turn facilitate the development of better treatment strategies to combat TNBC.

PPARγ Ligand-induced Annexin A1 Expression Determines Chemotherapy Response via Deubiquitination of Death Domain Kinase RIP in Triple-negative Breast Cancers

Metastatic breast cancer is still incurable so far; new specifically targeted and more effective therapies for triple-negative breast cancer (TNBC) are required in the clinic. In this study, our clinical data have established that basal and claudin-low subtypes of breast cancer (TNBC types) express significantly higher levels of Annexin A1 (ANXA1) with poor survival outcomes. Using human cancer cell lines that model the TNBC subtype, we observed a strong positive correlation between expression of ANXA1 and PPARγ. A similar correlation between these two markers was also established in our clinical breast cancer patients' specimens. To establish a link between these two markers in TNBC, we show de novo expression of ANXA1 is induced by activation of PPARγ both in vitro and in vivo and it has a predictive value in determining chemosensitivity to PPARγ ligands. Mechanistically, we show for the first time PPARγ-induced ANXA1 protein directly interacts with receptor interacting protein-1 (RIP1), promoting its deubiquitination and thereby activating the caspase-8-dependent death pathway. We further identified this underlying mechanism also involved a PPARγ-induced ANXA1-dependent autoubiquitination of cIAP1, the direct E3 ligase of RIP1, shifting cIAP1 toward proteosomal degradation. Collectively, our study provides first insight for the suitability of using drug-induced expression of ANXA1 as a new player in RIP1-induced death machinery in TNBCs, presenting itself both as an inclusion criterion for patient selection and surrogate marker for drug response in future PPARγ chemotherapy trials. Mol Cancer Ther; 16(11); 2528-42. ©2017 AACR.

Belinostat exerts antitumor cytotoxicity through the ubiquitin-proteasome pathway in lung squamous cell carcinoma

There have been advances in personalized therapy directed by molecular profiles in lung adenocarcinoma, but not in lung squamous cell carcinoma (SCC). The lack of actionable driver oncogenes in SCC has restricted the use of small‐molecule inhibitors. Here, we show that SCC cell lines displayed differential sensitivities to belinostat, a pan‐histone deacetylase inhibitor. Phosphoproteomic analysis of belinostat‐treated SCC cells revealed significant downregulation of the MAPK pathway, along with the induction of apoptosis. In cisplatin‐resistant cells that demonstrated aberrant MAPK activation, combined treatment with belinostat significantly inhibited cisplatin‐induced ERK phosphorylation and exhibited strong synergistic cytotoxicity. Furthermore, belinostat transcriptionally upregulated the F‐box proteins FBXO3 and FBXW10, which directly targeted son of sevenless (SOS), an upstream regulator of the MAPK pathway, for proteasome‐mediated degradation. Supporting this, suppression of SOS/ERK pathway by belinostat could be abrogated by inhibiting proteasomal activity either with bortezomib or with siRNA knockdown of FBXO3/FBXW10. Taken together, these preclinical data offer a novel understanding of the epigenetic mechanism by which belinostat exerts its cytotoxicity and supports the combination with cisplatin in clinical settings for chemorefractory SCC tumors.

Genomic predictors of neoadjuvant chemotherapy (NACT) response in breast cancer (BC)

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Background: We assessed effects of NACT on BC mutational landscape. Methods: Baseline (BL) and post-NACT tumor / matched normal DNA from 12 newly diagnosed BC patients on NACT (4 x doxorubicin/cyclophosphamide + low dose sunitinib; NCT01176799) were subject to whole exome sequencing. Nonsynonymous somatic single nucleotide variants from 34 genes in known BC signaling pathways were evaluated for changes in mutant variant allele frequency (VAF) according to clinical outcome. Poor outcome was defined as <50% target lesion reduction after NACT or BC relapse / progression (PD) within 2 years; significant change was defined as > 0.2 difference in BL vs post-NACT mutant VAF. Results: Mean tumor size was 6.4 + 2.9cm; 50% were N+; 8% were M1; 7/12 patients had poor outcomes. Tumors harbored mutations in PI3K (58%), NOTCH (42%), Wnt (42%), TP53 (33%) and FOXA (17%) pathways. Change in no. of somatic mutations post-NACT correlated with outcome (mean percent change +14% vs -30% in patients with poor vs good outcome, p=0.04). 11 patients had >1 of 23 putative driver mutations identified ( Table 1). Mutant VAF declined significantly in those with good outcomes, except for a new NOTCH2 mutation in A2 and rise in mutant VAF in A4. In patients with poor outcomes, mutant VAF persisted or rose, and emergent mutations (AKT1, PIK3CA) occurred in 2 patients. Conclusions: Chemoresistance and emergent mutations were revealed by tracking mutant VAF in BC patients on NACT. Clinical trial information: NCT01176799. [Table: see text]

Whole exome sequencing (WES) of multiple spatially distinct biopsies from single metastatic lesions to evaluate tumour heterogeneity and identify actionable truncal mutations (ATMs) in patients (pts) with advanced solid malignancies using a radiologically-guided single-pass percutaneous technique

2550

Background: Genomic profiling of single core biopsies (bx) are confounded intratumoral heterogeneity, resulting in sampling bias. We explored the use of a novel technique to obtain multiple bx from single metastatic lesion in pts to evaluate heterogeneity and identify therapeutic ATM. Methods: 15 pts (5 NSCLC; 3 ovarian; 2 colon, 2 uterine and 1 breast, cervix and HCC) with biopsiable lesions were identified. Using a single pass radiologically guided percutaneous bx technique, we obtained multiple spatially distinct core bx samples from a single metastatic lesion. Each bx underwent DNA extraction and WES using the NextSeq500. Results: Median of 4 core bx were obtained from each lesion. Complication rate utilizing this technique was 0%. 2 pts were omitted from analysis due to poor quality DNA with 13 pts successfully sequenced. In 1 pt, only 2 of 4 cores were successfully sequenced. The median amounts of total and non-synonymous variants were 137 (27-1286) and 66 (10-649) respectively. The median (range) filtered variants detected in 1/4, 2/4, 3/4, and 4/4 bx cores was 63(16-91)%, 5(1-65)%, 4(0-30)% and 26(0-63)% respectively, suggesting significant subclonal diversity within a single lesion. ATMs were identitified in 8/13 pts. 4/13 pts (31%) had no ATM across all 4 cores. 3 pts received therapy with inhibitors targeting ATMs. A pt with AKT1_E17K ATM received an AKT inhibitor with 21% tumour shrinkage and PFS 6.1 mths. 2 NSCLC pts harbouring an EGFR_T790M ATM were treated with an EGFRT790M specific TKI. 1 withdrew due to toxicity after 2mths and another had PFS > 16.5 mths. Tumour mutational burden (TMB) was consistent across multiple bx from each lesion. A NSCLC pt with the highest TMB received a checkpoint inhibitor with ongoing > 4 mths stable disease. Conclusions: Utilizing a single pass radiologically guided techniqueto obtainmultiple bx is feasible, safe and informative. This allows reconstruction of a tumour’s subclonal genomic architecture, providing insights into mutational heterogeneity and help guide therapy.

A phase Ib study of selumetinib (AZD6244, ARRY-142886) in combination with sorafenib in advanced hepatocellular carcinoma (HCC)

BACKGROUND

Treatment with sorafenib, although associated with inhibition of tumour growth and angiogenesis in in vivo studies, leads to up-regulation of pERK. The addition of MEK inhibition could potentially abrogate this effect and potentiate anti-tumour activity. This phase I study investigated the maximum tolerated dose (MTD), safety, tolerability, pharmacokinetics (PK) and biomarker correlates of selumetinib combined with sorafenib in patients with advanced hepatocellular carcinoma (HCC).

METHODS

Patients with Child-Pugh (CP) score ≤7 were treated with 400 mg twice daily of sorafenib with escalating doses of selumetinib in a 3 + 3 study design. The dose-limiting toxicity (DLT) evaluation period was 28 days. PK of selumetinib was determined. Angiogenic effect was evaluated with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

RESULTS

Twenty-seven patients of Asian ethnicity were enrolled. The MTD was selumetinib 75 mg daily with sorafenib 400 mg twice daily. DLT included grade 3 transaminitis, diarrhoea and fatigue. Most common treatment-related adverse events at MTD (all grades) were diarrhoea (85%), rash (59%), hypertension (44%), fatigue (30%), anorexia (22%) and hand-foot syndrome (22%). Four patients (15%) had PR and 13 (48%) had SD. PR or SD was observed for ≥6 months in seven patients. The median overall survival was 14.4 months. Selumetinib exposures in combination with sorafenib were comparable to other monotherapy studies. A reduction in permeability-surface area product noted in DCE-MRI with treatment correlated with worse survival outcomes.

CONCLUSION

The MTD of selumetinib was 75 mg daily when combined with sorafenib 400 mg twice a day in CP ≤7 HCC. Acceptable adverse events and encouraging anti-tumour activity warrant further evaluation. DCE-MRI findings deserve prospective evaluation.

CLINICALTRIALSGOV IDENTIFIER

NCT01029418.

Phenotyping of UGT1A1 Activity Using Raltegravir Predicts Pharmacokinetics and Toxicity of Irinotecan in FOLFIRI

Background

Irinotecan toxicity correlates with UGT1A1 activity. We explored whether phenotyping UGT1A1 using a probe approach works better than current genotyping methods.

Methods

Twenty-four Asian cancer patients received irinotecan as part of the FOLFIRI regimen. Subjects took raltegravir 400 mg orally and intravenous midazolam 1 mg. Pharmacokinetic analyses were performed using WinNonLin and NONMEM. Genomic DNA was isolated and screened for the known genetic variants in UGT1A1 and CYP3A4/5.

Results

SN-38G/SN-38 AUC ratio correlated well with Raltegravir glucuronide/ Raltegravir AUC ratio (r = 0.784 p<0.01). Midazolam clearance correlated well with irinotecan clearance (r = 0.563 p<0.01). SN-38 AUC correlated well with Log10Nadir Absolute Neutrophil Count (ANC) (r = -0.397 p<0.05). Significant correlation was found between nadir ANC and formation rate constant of raltegravir glucuronide (r = 0.598, P<0.005), but not UGT1A1 genotype.

Conclusion

Raltegravir glucuronide formation is a good predictor of nadir ANC, and can predict neutropenia in East Asian patients. Prospective studies with dose adjustments should be done to develop raltegravir as a probe to optimize irinotecan therapy.

Trial Registration

Clinicaltrials.gov NCT00808184

Phase I and biomarker study of OPB-51602, a novel signal transducer and activator of transcription (STAT) 3 inhibitor, in patients with refractory solid malignancies

BACKGROUND

The aim of this study was to determine the maximum-tolerated dose (MTD), safety, pharmacokinetics, and pharmacodynamics of OPB-51602, an oral, direct signal transduction activator of transcription 3 (STAT3) inhibitor, in patients with refractory solid tumors.

PATIENTS AND METHODS

Three cohorts were studied: cohort A, a sequential dose escalation of OPB-51602 administered intermittently (days 1-14 every 21 days); cohort B, an expansion cohort evaluating the dose lower than the MTD; cohort C, evaluating continuous daily dosing.

RESULTS

Fifty-one patients were studied at 2, 4, and 5 mg per day dosing. The MTD was 5 mg; first-cycle dose-limiting toxicities (DLTs) were grade 3 hyponatremia in one patient, and grade 3 dehydration in another. Intermittent dosing of both 2 and 4 mg doses were tolerable, and the recommended phase II dose was 4 mg. Cohort B investigated 4 mg intermittently, whereas cohort C investigated 4 mg continuously. Common toxicities included fatigue, nausea/vomiting, diarrhea, anorexia, and early-onset peripheral neuropathy. Drug-induced pneumonitis occurred in two patients in cohort C. Continuous dosing was associated with a higher incidence of peripheral neuropathy and a lower mean relative dose intensity, compared with intermittent dosing. Steady-state pharmacokinetics was characterized by high oral clearance, mean elimination half-life ranging from 44 to 61 h, and a large terminal-phase volume of distribution. An active metabolite, OPB-51822, accumulated to a greater extent than OPB-51602. Flow cytometry of peripheral blood mononuclear cells demonstrated pSTAT3 (Tyr(705)) inhibition following exposure. Two patients achieved partial responses at 5 mg intermittently and 4 mg continuously; both had epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC) with prior EGFR tyrosine kinase inhibitor exposure.

CONCLUSION

OPB-51602 demonstrates promising antitumor activity, particularly in NSCLC. Its long half-life and poorer tolerability of continuous dosing, compared with intermittent dosing, suggest that less frequent dosing should be explored.

CLINICALTRIALSGOV IDENTIFIER

NCT01184807.

A phase IB trial of 5-azacitidine (5AC) and suberoylanilide hydroxamic acid (SAHA) in patients with metastatic or locally recurrent nasopharyngeal carcinoma (NPC) and NK-T cell lymphoma

e17017

Background: Epigenetic up-regulation of EBV and cellular genes via demethylation and histone deacetylase inhibition can induce EBV lytic replication enhancing immune mediated tumor killing and up-regulation of tumor suppressor genes resulting in tumor apoptosis. Methods: Patients (Pt) with relapsed or refractory NPC and NK-T cell lymphomas were enrolled to determine safety, tolerability, pharmacokinetics (PK), pharmacodynamics and preliminary anti-tumor activity using a dose escalation design. 5AC was administered on days 1 to 10 sub-cutaneously while SAHA was administered on days 1 to 14 orally. PK for SAHA, EBV viral load, characterization of circulating EBV, Immunohistochemistry (IHC) and EBV promoter methylation analysis in tumor tissue were performed. Results: 11 pt have been treated (M:F 8:3, median age 48, R: 35-71) at 3 dose levels – 5AC 50 mg/m2 and SAHA 200 mg b.i.d. (dose level 1), 5AC 37.5 mg/m2 and SAHA 200 mg q. am and 100 mg q. pm (dose level 2), and 5AC 25 mg/m2 and SAHA 100 mg b.i.d (dose level 3). Median number of previous treatment regimens was 3 (R:1-6). Dose limiting toxicities (DLT) were seen in 2/2 pts at dose level 1: grade 4 thrombocytopenia (1 pt), grade 3 nausea, vomiting and fatigue (2 pts), and grade 5 hepatic failure (1 pt). Two of six patients at dose level 2 experienced DLT: grade 3 fatigue (1 pt) and worsening of pre-existing Sweet’s Syndrome (1 pt). Common AEs (G1/2) included fatigue (73%), cough (64%), anorexia (55%), and injection site reaction (45%). One minor response was seen and 5 pt had prolonged stable disease (>16 weeks), including one patient for 88 weeks. Analysis of post-treatment tumor biopsies showed demethylation of EBV lytic cycle gene promoters after treatment. SAHA PK, IHC results for EBV gene expression in tumor tissue, EBV viral load and characterization of circulating EBV will be presented. Conclusions: 5AC/SAHA appears to be tolerable at dose level 3 with suggestion of clinical benefit. Analysis of post-treatment tumor and blood samples suggests that modulation of EBV gene expression may play a role in the mechanism underlying clinical benefit. Continued accrual at dose level 3 is ongoing. Clinical trial information: NCT00336063.

Pharmacodynamic effects of regorafenib in metastatic colorectal carcinoma (mCRC)

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Background: Regorafenib, an oral multikinase inhibitor of VEGFR2/3, PDGFRb, KIT, FGFR, RET, RAF and TIE2, is efficacious in refractory mCRC but its mechanism of action is unclear and predictive biomarkers are lacking. Methods: We assessed tumor and circulatory biomarkers in a phase 2 study of regorafenib in refractory mCRC patients. Regorafenib was administered orally at 160mg/d for 3 out of 4 weeks. Post cycle 2 response was assessed by RECIST 1.1. Subjects were scheduled for FDG PET-CT scans (pre + D15) and paired core needle tumor biopsies for IHC analysis (pre + D21) in cycle 1. Archival tumor mutations were evaluated using Sequenom MassARRAY OncoCarta Panel V1.0 assay. Results: 35 patients were treated; 49% received > 4 prior therapies and 43% had prior bevacizumab. Median PFS was 3.45 mths (95% CI: 3.40-3.49), ORR was 3% and disease control rate [DCR] (PR + SD at 8 wks) was 57%. Early PET responses (EORTC criteria) were seen in 49%, but did not predict for DCR (p=1.0). Fatigue, hand foot skin reaction (HFSR), voice change and diarrhea occurred in > 30% of subjects. Grade 3-5 toxicities occurred in 46%, the commonest being HFSR and rash (17% each). Median relative dose intensity was 92%; 43% required > 1 dose reduction, 60% required > 1 dose interruption. KRAS (29%), BRAF (9%), EGFR (9%), NRAS (6%) KIT (3%), PIK3CA (3%), PDGFRA (3%) and CDK (3%) mutations were detected in archival tumors. None predicted for ORR or DCR; PFS was identical in KRAS mutant vs wt patients (3.45 mths, p=0.39) and similar in BRAF mutant vs wt patients (3.48 vs 3.45 mths, p=0.10). The patient with the longest PFS (12.6 mths) had a BRAF mutation. Amongst the 10 paired tumor samples available, IHC markers upregulated in >50% cases were pMEK, pERK, pJun and pJNK, whilst those downregulated/ unchanged in >50% were pKIT, pVEGFR2, CD31 [vascular endothelial cells (ECs)] and podoplanin (lymphatic ECs). The greatest change was observed in podoplanin expression, corresponding to a 60% reduction in lymphatic vessel density. Conclusions: FDG-PET responses in cycle 1 did not predict for regorafenib clinical benefit in mCRC patients. Targeting lymphatic/vascular ECs in the tumor microenvironment may be a more significant antitumor mechanism of regorafenib than MAP kinase pathway inhibition. Clinical trial information: NCT01189903.

A blood-based epigenetic test for early detection of nasopharyngeal carcinoma (NPC)

6063

Background: NPC is highly curable in early stages but 70% of NPC patients are diagnosed with advanced disease due to lack of effective screening. Genetic and epigenetic alterations involved in the pathogenesis of NPC are known. The higher order chromosomal structures reflecting aberrant transcriptional states of these genes can be measured via techniques such as chromosome conformation capture. Detection of these changes in peripheral blood may provide an accurate test for the early cancer detection. Methods: Blood samples have been collected from 84 patients with histologically confirmed NPC and 100 matched controls. Samples from 45 NPC patients and 68 controls have been analyzed. Fourteen genes known to be dysregulated in NPC were investigated. Potential higher order juxtaposition sites in the candidate genes were predicted using pattern recognition software. PCR primer sets were designed around the chosen sites to screen potential markers. Twenty-two markers showing predictability between NPC and control samples were analysed for optimal reproducibility using alternative primer sets. The optimal sets of markers were then tested amongst the complete set of samples. The dataset was processed by re-sampling using the synthetic minority oversampling technique. The overall sample was split into two groups (66% training set and 34% test set) in the classification. Results: Sixteen markers from 7 candidate genes were found to be optimal in differentiating between NPC and control samples in the first 103 samples. Using the multilayer perceptron (MLP) classification, the following results were obtained: Sensitivity 88.9%, 95% CI (79.2% - 98.6%); Specificity 72.7%, 95% CI (58.9% - 86.5%); PPV 72.7%, 95% CI (58.9% - 86.5%); NPV 88.9%, 95% CI (79.2% - 98.6%). The accuracy of the test was similar in detection of stage I and II NPC versus that of stage III or IV NPC. Conclusions: Using a PCR-based method to detect alterations in the cancer epigenome, the feasibility of developing a blood test of potential utility in early diagnosis of NPC was demonstrated. Analysis of larger numbers of patient samples and optimization of markers are ongoing. The performance characteristics of the test in the total population of 184 samples will be presented.

Epigenetic therapy using belinostat for patients with unresectable hepatocellular carcinoma: a multicenter phase I/II study with biomarker and pharmacokinetic analysis of tumors from patients in the Mayo Phase II Consortium and the Cancer Therapeutics Research Group

PURPOSE

Epigenetic aberrations have been reported in hepatocellular carcinoma (HCC). In this study of patients with unresectable HCC and chronic liver disease, epigenetic therapy with the histone deacetylase inhibitor belinostat was assessed. The objectives were to determine dose-limiting toxicity and maximum-tolerated dose (MTD), to assess pharmacokinetics in phase I, and to assess activity of and explore potential biomarkers for response in phase II.

PATIENTS AND METHODS

Major eligibility criteria included histologically confirmed unresectable HCC, European Cooperative Oncology Group performance score ≤ 2, and adequate organ function. Phase I consisted of 18 patients; belinostat was given intravenously once per day on days 1 to 5 every 3 weeks; dose levels were 600 mg/m(2) per day (level 1), 900 mg/m(2) per day (level 2), 1,200 mg/m(2) per day (level 3), and 1,400 mg/m(2) per day (level 4). Phase II consisted of 42 patients. The primary end point was progression-free survival (PFS), and the main secondary end points were response according to Response Evaluation Criteria in Solid Tumors (RECIST) and overall survival (OS). Exploratory analysis was conducted on pretreatment tumor tissues to determine whether HR23B expression is a potential biomarker for response.

RESULTS

Belinostat pharmacokinetics were linear from 600 to 1,400 mg/m(2) without significant accumulation. The MTD was not reached at the maximum dose administered. Dose level 4 was used in phase II. The median number of cycles was two (range, one to 12). The partial response (PR) and stable disease (SD) rates were 2.4% and 45.2%, respectively. The median PFS and OS were 2.64 and 6.60 months, respectively. Exploratory analysis revealed that disease stabilization rate (complete response plus PR plus SD) in tumors having high and low HR23B histoscores were 58% and 14%, respectively (P = .036).

CONCLUSION

Epigenetic therapy with belinostat demonstrates tumor stabilization and is generally well-tolerated. HR23B expression was associated with disease stabilization.

A multi-institutional phase II trial of pazopanib monotherapy in advanced anaplastic thyroid cancer

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Background: Pazopanib, an orally bioavailable multitargeted inhibitor of kinases including VEGF-R, demonstrated impressive activity in metastatic differentiated thyroid cancer (49% durable RECIST PRs) and promising preclinical activity in anaplastic thyroid cancer (ATC) models, prompting its evaluation also as a candidate therapeutic in advanced ATC. Methods: A multicenter single arm phase II trial of 800 mg pazopanib daily was undertaken with the primary endpoint of RECIST response rate. The trial was designed such that there would be a 90% chance of detecting a response rate of >20% at the 0.10 significance level when the true tumor response rate is >5%. A pre-specified stopping rule designated that enrollment would cease unless 1 or more RECIST PRs+CRs were observed in the first 14 of 33 potential patients. Eligibility required informed consent, >18 years of age, performance status ECOG 0-2, systolic blood pressure (BP) <140 mm Hg and diastolic BP <90 mm Hg at entry, QTc interval <480 msecs, and measurable disease by RECIST criteria. Anatomical imaging and toxicity evaluations were required every 4 weeks. Results: Sixteen patients were enrolled. One patient withdrew prior to therapy, leaving 15 evaluable patients – 33.3% were male, with a median age of 66 years (range 45-77); 11 of 15 patients had progressed through prior systemic therapy. Four patients required 1-2 dose reductions, with the most common severe toxicities (CTC-AE version 3.0 grades 3-5) hypertension (13%) and pharyngolaryngeal pain (13%). Reasons for treatment discontinuation included: disease progression (12 pts), death on study due to a vascular event possibly related to treatment (1 pt.), and intolerability (radiation recall tracheitis – 1 pt, and uncontrolled hypertension – 1 pt). Although transient disease regression was observed in several patients, there were no confirmed RECIST tumor responses, triggering study closure at time of interim analysis. Two patients are alive with disease 9.9 months and 2.9 years post-registration; the remaining 13 died of disease. The median time to progression was 62 days and the median survival time was 111 days. Conclusions: Pazopanib has poor single agent activity in advanced anaplastic thyroid cancer.

Thymidylate synthase genotype specific dosing of capecitabine: Proof of concept phase I study

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Background: Thymidylate synthase (TYMS) is the target of fluoropyrimidines (FP). TYMS 3R3R is the predominant genotype in East Asian (EA) patients and is associated with increased TYMS expression, reduced FP related toxicity and relative FP resistance. Dose finding studies for FP were developed in Caucasians, a population that typically harbors TYMS 2R2R and 2R3R genotypes. We hypothesize the recommended phase II dose (RP2D) of capecitabine is higher in 3R3R and similar for 2R allele carriers compared to the FDA approved dose. Objectives 1) To determine the maximal tolerated dose (MTD) and RP2D of capecitabine in EA patients with advanced stage malignancy 2) To determine the safety and toxicity of this regimen and 3) To perform plasma pharmacokinetics (PK) of capecitabine and its metabolites. Methods: EA patients with advanced stage cancer were prospectively allocated into two cohorts: Group A (3R3R) and Group B (2R3R, 2R2R). In each cohort, dose escalation followed a standard phase I 3+3 design. Additional patients were treated at the R2P2 dose level (DL). Initial dose was 1250/m2 bd for 14 days q3w (DL 1) with 125 mg/m2 bd increments subsequently. Pharmacokinetics (PK) of capecitabine and its metabolites were performed using a LC-MS/MS method. Results: 23 patients (Group A=18; group B=5) received 94 cycles (median 2.5, range 1-8). Median age was 58 (range 34-74) years. Median turnaround time for TYMS genotyping was 1 day. In group A, grade 3-4 DLTs were seen in 3 patients: diarhoea, neutropenic fever, hand-foot syndrome, and mucositis. MTD was at DL 4 (1625mg/m2 bd) and the RP2D was 1500mg/m2 bd (DL 3). DL 3 was expanded to n=9. At DL 3, day 1 mean (± SD) capecitabine and 5FU Cmax was 12.3 ± 9.9 and 0.91 ± 0.73 µg/mL, respectively and AUC0 – t was 9.84 ± 5.53 and 1.21 ± 0.54 h*µg/mL, respectively. Compared with DL1, Cmax for capecitabine and 5FU was 2 and 2.02 fold higher and AUC 0-t was 1.49 and 1.59 fold higher at DL3. Accrual in group B was ceased at DL2 due to lack of patient enrolment; no DLT was seen. By ROC analysis, day 1 5FU AUC0 – t of 1.74 h*µg/mL predicted for DLT (p=0.022, sensitivity 100%, specificity 90%). Conclusions: In EA patients with TSER 3R3R, the RP2D was 1500 mg/m2 bd. The D1 5FU AUC0 – t at RP2D was 59% more than the FDA approved dose (DL1).

Phase I study of OPB51602, a small molecule inhibitor of STAT3 phosphorylation, in patients with refractory solid malignancies

3002

Background: STAT3 is constitutively activated by growth signaling pathways in many malignancies; in many cell lines inhibition of STAT3 leads to cell death. OPB51602 is a small molecule inhibitor of STAT3 phosphorylation (Tyr705) and activation. Methods: A phase I study of OPB51602 administered for 2 weeks every 3 weeks was initiated to determine the maximum tolerable dose (MTD), evaluate pharmacokinetics (PK), and assess pharmacodynamics effects on STAT3 in peripheral blood mononuclear cells (PBMCs). The starting dose was 2mg/day, and dose escalations to 5mg/d, 10mg/d, 20mg/d, were planned. Single dose PK was done on the first day of administration for 4 days. Dose escalation was based on the “3+3” design, MTD was defined as the dose with at least 2/6 dose limiting toxicities (DLTs) in the first cycle and toxicities were graded by NCICTCv4.0. Results: 32 patients (pt) were treated at doses of 2mg/d (n=7), 4mg/d (n=18), 5mg/d (n=7). The main toxicities observed included nausea/vomiting, diarrhea, peripheral neuropathy and fatigue. 5 mg/d was the MTD, where cycle 1 DLTs of grade 3 diarrhea/dehydration and hyponatremia occurred in 1 patient respectively. One pt developed grade 3 peripheral neuropathy at 4mg/d cohort. PK showed maximal drug levels 2-3 hours after administration, bi-exponential decay, with mean oral clearance of 316.5 +/- 638.9 L/h and long terminal mean half-life of 61.8 +/- 15.9 h on day 17. STAT3 phosphorylation in PBMCs assessed in 6 pts receiving 4mg/d was reduced from 67.4 +/- 17.4% at baseline to 53.0 +/- 18.1% (p=0.001) after administration on day 1. Interestingly, reduction in tumor metabolism by PET CT on day 15 was observed in 4/8 pts receiving 4mg/d. A pt with heavily pretreated adenocarcinoma of lung at 5mg/d dose had partial response; another pt with metastatic endometrial cancer at 4mg/d dose experienced stable disease for 6 cycles. Conclusions: OPB51602 has an MTD of 5mg/d on this schedule, demonstrates inhibition of STAT3 phosphorylation, and evidence of clinical activity. Further proof of concept studies of OPB51602 are warranted.

Correlation of pharmacokinetics of CPT-11 in FOLFIRI with phenotyping of CYP3A4 and UGT1A1 activity

e13002

Background: CPT-11 has complex PK and PD; genotyping of UGT1A1 is recommended for higher doses in *28 carriers (Caucasian) and *6 carriers (Asian) because of a higher risk of toxicity. Raltegravir is mainly metabolized to raltegravir glucuronide by UGT1A1. CPT-11 is mainly eliminated by cytochrome P450 isoform 3A (CYP3A)-mediated oxidation and by esterase cleavage to form SN-38, which is further conjugated by uridine-diphosphate glucuronosyltransferase (UGT) isozymes to the inactive SN-38 glucuronide. We prospectively explored the correlation of midazolam and raltegravir PK with CPT-11 clearance (CL) and SN-38 levels respectively and toxicity in patients undergoing chemotherapy with CPT-11. Methods: Twenty-five Asian patients with advanced cancer received CPT-11 as a 2-weekly 90-minute infusion (180 mg/m2) as part of the FOLFIRI regimen. Subjects were administered raltegravir 400 mg orally (as a UGT1A1 probe) and intravenous midazolam 1 mg (as a CYP3A4 probe) one day before the first dose of their chemotherapy. Blood sampling for drug concentrations was performed for 2 days after probe drug administration. Non-compartmental PK analyses were performed using WinNonLin. Genomic DNA was isolated and screened for the known genetic variants in UGT1A1*6. Results: One patient developed grade 3 diarrhea and 16 developed grade 3-4 neutropenia. The mean CPT-11 CL was 21.9 + 7.8L/h. SN-38G/SN-38 AUC ratio was highly correlated with Raltegravir glucuronide/ Raltegravir AUC ratio (r=0.784 p<0.01). Midazolam CL was highly correlated with CPT-11 CL (r=0.563 p<0.01). SN38 AUC correlated well with neutropenia (Log10Nadir Absolute Neutrophil Count (ANC) (r=-0.397 p<0.05). Neither CPT-11 nor midazolam CL correlated with Log10 Nadir ANC. Of the 24 patients with genotyping of UGT1A1*6 done, 17 were wild type (GG), 7 heterozygotes (AG) and 0 were mutant (AA). No differences in toxicity or SN38 pharmacokinetics were observed in the UGT1A1*6 variants. Conclusions: Raltegravir glucuronide ratio is a good predictor of SN-38 glucuronidation, and has potential to predict neutropenia from FOLFIRI treatment. Prospective studies with dose adjustments should be done to develop raltegravir as a probe to optimize CPT-11 therapy.

Low-dose, short-course sunitinib may normalize tumor vasculature and improve tumor blood flow to enhance chemotherapy efficacy in breast cancers

1064

Background: Small molecule VEGFR inhibitors (VEGFR-I) have failed to improve outcome with chemotherapy in most solid tumors. Continuous administration of a potent VEGFR-I may destroy vasculature and impede drug delivery; in contrast, low-dose, short-course VEGFR-I before chemotherapy may normalize tumor vasculature and enhance drug delivery. Methods: We conducted a phase Ib followed by phase II randomized study in patients with measurable primary breast tumors using low-dose sunitinib (Su) for 1 week prior to doxorubicin/cyclophosphamide (AC) and measured tumor blood flow with DCE-MRI and microvessel density and pericyte recoverage with CD31 and α-smooth muscle actin (SMA) staining on tumor biopsies, at baseline, after 1 week of Su, and 2 weeks after cycle 1 AC. Patients in phase Ib received 12.5-25mg Su prior to AC; in phase II, patients were randomized to AC+/-12.5mg Su. Results: 21 patients have been enrolled, including 3 patients on 25mg Su+AC, 11 on 12.5mg Su+AC, and 7 on AC alone. After 1 week of 25mg Su, 2/3 patients had reduced tumor blood flow on DCE-MRI indicating anti-angiogenic effects. After 1 week of 12.5mg Su, significant increase in tumor fractional plasma volume (Vp) occurred (+28%±28%, p=0.025) suggesting increased perfusion, followed by decrease 2 weeks after AC (-33%±26%,p=0.035) corresponding to mean tumor size change of -17±15%, while no significant Vp changes occurred with AC alone (p=0.823); CD31 expression reduced (20.7 vs 15.7, p=0.173) while SMA/CD31 double staining increased (2.45 vs 7.34, p=0.046) indicating lower microvessel density and normalization of residual vasculature, which was not seen with AC alone (CD31, p=0.434; CD31/SMA, p=0.605). The main toxicity of Su+AC and AC alone was febrile neutropenia (29% vs 43%). 14 patients had surgery with pathological complete response in 1/6 patients who received 12.5mg Su+AC. Conclusions: 25mg Su for 1 week can reduce tumor blood flow, suggesting that concomitant standard dose Su may compromise drug delivery. Low dose 12.5mg Su for 1 week is sufficient to normalize tumor vasculature and increase tumor fractional plasma volume, and may potentially improve drug delivery and treatment outcome.

A phase I/II study of AZD6244 in combination with sorafenib in advanced hepatocellular carcinoma

4100^

Background: Preclinical studies have shown that pharmacological inhibition of the MEK/ERK pathway by AZD6244 enhanced the anti-tumor effect of sorafenib in both orthotopic and ectopic models of HCC. We conducted this study to determine tolerability, pharmacokinetics, and pharmacodynamics of AZD6244 when combined with sorafenib in advanced HCC. Methods: Patients with biopsy-proven unresectable BCLC B/C hepatocellular carcinoma were recruited. Only those with Childs-Pugh A or B (7) liver cirrhosis and without prior systemic therapy were included. Sorafenib at 400mg bd was given 1 week before initiation of AZD6244 which was escalated in subsequent cohorts from 75mg om based on 3+3 design. PK and PD studies and QOL assessments were performed. DCE-MRI imaging was performed to assess tumor vascularity in response to treatment. Results: Fourteen patients were recruited (including 2 replaced). 11 had evaluable disease. Characteristics: all male, all Chinese, 12 were BCLC C stage. Two DLTs were seen out of 6 patients at dose level 1 (AZD6244 at 50mg bd) which were grade 3 fatigue and grade 3 abdominal pain with elevated transaminases. When an additional dose level 1A was added (ADZ6244 at 100mg om), 2 out of 3 patients had DLTs of grade 3 raised aspartate transaminase and grade 3 diarrhea. Thus, the MTD was determined to be AZD6244 at 75mg om when combined with sorafenib 400mg bd. Common toxicities were diarrhea (83%), rash (58%), fatigue (50%), hypertension (42%), anorexia/vomiting/thrombocytopenia (25%). Two patients had reversible LVEF dysfunction and there were no eye toxicities. PK of AZD6244 showed oral clearance of 11.2 + 6.8 L/h and terminal half-life of 6.0 +2.0 h.Objective responses were 3 PR, 6 SD and 2 PD.DCE-MRI measurements demonstrated significant reductions in permeability surface area product (PS, ml/100ml/min) and fractional intravascular blood volume (v1, ml/100ml) seven days after starting sorafenib. No additional antivascular activity was observed when AZD6244 was added to sorafenib. Conclusions: The recommended phase II dose for AZD6244 is 75mg om when combined with sorafenib 400mg bd for advanced HCC patients. This combination is feasible, shows activity and warrants further investigation.

Efficacy of belinostat in advanced hepatocellular carcinoma (HCC): Phase I and II multicentered study of the Mayo Phase 2 Consortium (P2C) and the Cancer Therapeutics Research Group (CTRG)

259

Background: Belinostat is a novel histone deactylase inhibitor which demonstrates preclinical activity in HCC. We report the results of a phase I/II study on belinostat in patients (pts) with unresectable HCC.

Methods: Major eligibility criteria included histologically confirmed HCC not amenable to curative treatment; PS ≤ 2; adequate organ function; prior systemic therapy was allowed. In the phase I portion, belinostat was given i.v. on D1-5 every 3 weeks with dose levels of 600, 900, 1200 and 1400 mg/m2/day. In the phase II portion, belinostat was tested at the MTD. Primary endpoint was PFS and secondary endpoints were RR according to RECIST and OS. CT assessment was done every 8 weeks.

Results: Phase I portion: a total of 18 pts were accrued; no DLTs were observed at 1400mg/m2/day for 5 days, and this dose was selected for phase II development. Phase II portion: 42 pts were accrued; Median age = 57.5 years; 41 had Child’s A function, and 24 pt had ECOG 0. Sixteen (38%) had previous systemic therapy, and 21 (50%) had previous transarterial therapy. Median follow-up was 20.0 months. The PR and SD rate was 2.4% (1/42) and 45.2% (19/42). Median PFS was 2.64 months (95%C.I. 1.55-3.17) and OS was 6.60 months (95%C.I. 4.53-11.60). Grade 3 or higher toxicities (>5% rate) were abdominal pain (9.5%), (9.5%) hyperbilirubinemia (9.5%), raised ALT (9.5%); anemia (7.1%) and vomiting (7.1%).

Conclusions: Belinostat demonstrates disease stabilization in a predominantly pretreated population of pts with unresectable HCC with an acceptable safety profile. Further randomized studies are warranted.Supported in part by N01-CM-62205.

Ovariectomy and genes encoding core circadian regulatory proteins in murine bone

SUMMARY

This study investigated the influence of ovarian hormone deficiency on core circadian regulatory protein (CCRP) in the context of bone loss. Our data suggest that ovarian hormone deficiency disrupts diurnal rhythmicity and CCRP expression in bone. Further studies should determine if chronobiology provides a novel therapeutic target for osteoporosis intervention.

INTRODUCTION

CCRP synchronize metabolic activities and display an oscillatory expression profile in murine bone. In vitro studies using bone marrow mesenchymal stromal/stem cells have demonstrated that the CCRP is present and can be regulated within osteoblast progenitors. In vivo studies have shown that the CCRP regulates bone mass via leptin/neuroendocrine pathways. The current study used an ovariectomized murine model to test the hypothesis that ovarian hormone deficiency is associated with either an attenuation and/or temporal phase shift of the CCRP oscillatory expression in bone and that these changes are correlated with the onset of osteoporosis.

METHODS

Sham-operated controls and ovariectomized female C57BL/6 mice were euthanized at 4-h intervals 2 weeks post-operatively.

RESULTS

Ovariectomy attenuated the oscillatory expression of CCRP mRNAs in the femur and vertebra relative to the controls and reduced the wheel-running activity profile.

CONCLUSION

Ovarian hormone deficiency modulates the expression profile of the CCRP with potential impact on bone marrow mesenchymal stem cell lineage commitment.

Phase I and pharmacodynamic study of an orally administered novel inhibitor of histone deacetylases, SB939, in patients with refractory solid malignancies

BACKGROUND

The objective of this study was to assess the safety, maximum tolerated dose (MTD), pharmacokinetics, pharmacodynamics, and preliminary efficacy of SB939, a novel histone deacetylase (HDAC) inhibitor, in patients with advanced solid malignancies.

PATIENTS AND METHODS

Dose-escalating cohorts of three to six patients received SB939 orally thrice weekly for 3 weeks in a 4-week cycle. Acetylated histone H3 (acH3) was measured in peripheral blood mononuclear cells (PBMCs).

RESULTS

Thirty patients treated at one of five doses (10-80 mg/day) received 79 cycles of SB939 (range, 1-12 cycles). Dose-limiting toxic effects were fatigue, hypokalemia, troponin T elevation, and QTc prolongation. Peak plasma concentration (C(max)) and area under the concentration-time curve extrapolated to infinity increased dose proportionally. The MTD of SB939 was 80 mg/day. The mean elimination half-life and oral clearance of SB939 were 7.2 ± 0.6 h and 53.0 ± 8.5 l/h, respectively, with no substantial accumulation on day 15. An increase in acH3 was observed at hour 3 and correlated with dose and C(max). Stable disease was seen in several tumor types treated at ≥40 mg. HDAC inhibition was consistently observed at 60 mg, the recommended dose.

CONCLUSIONS

SB939 can be safely administered at the recommended dose and reaches plasma levels that strongly inhibit HDAC in PBMCs. These data support further efficacy studies of SB939.

Serial changes in the expression of breast cancer-related proteins in response to neoadjuvant chemotherapy

BACKGROUND

Tumour expression of cyclooxygenase-2 (COX-2), epidermal growth factor receptor (EGFR), erythroblastic leukaemia viral oncogene homologue-2 (ErbB2), Ki-67 and p53 in breast cancer are associated with poorer outcomes. We investigated in vivo changes of these proteins with neoadjuvant chemotherapy.

PATIENTS AND METHODS

Four core biopsies were taken from 100 breast cancer patients at baseline, during and upon completion of neoadjuvant chemotherapy. Immunohistochemical expression of these proteins were evaluated and correlated with clinicopathological features, clinical response and progression-free survival (PFS).

RESULTS

There was a statistically significant change from positivity to negativity in COX-2 expression with chemotherapy (P = 0.002), predominantly in clinical responders (P = 0.002). COX-2-positive tumours that remained positive had shorter PFS than those that turned negative. Estrogen receptor (ER)+ and COX-2+ tumours at baseline that remained COX-2+ fared worse than those that became COX-2 negative (PFS 27 versus 52 months, P = 0.002). No significant changes in IHC expression were observed for ER, progesterone receptor, ErbB2, EGFR, p53 or Ki67.

CONCLUSIONS

Chemotherapy induced change in COX-2 expression from positivity to negativity predominantly among clinical responders and is associated with longer PFS. Interaction between COX-2 and ER was observed, suggesting that some hormone receptor-positive patients may benefit from combining COX-2 inhibition with hormonal therapy.

An evaluation of the drug interaction potential of pazopanib, an oral vascular endothelial growth factor receptor tyrosine kinase inhibitor, using a modified Cooperstown 5+1 cocktail in patients with advanced solid tumors

Pazopanib, an oral inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-kit kinases, inhibits multiple cytochrome P450 (CYP450) enzymes in vitro. This study in patients with advanced cancer evaluated the effect of pazopanib on CYP450 function by comparing the pharmacokinetics of CYP-specific probe drugs in the presence and absence of pazopanib. The probes used included midazolam (CYP3A specific), warfarin (CYP2C9 specific), omeprazole (CYP2C19 specific), caffeine (CYP1A2 specific), and dextromethorphan (CYP2D6 specific). The estimated ratios of the geometric means (90% confidence interval (CI)) for the area under the curve to the last measurable point (AUC(0-t)) for these probe drugs with/without pazopanib were as follows: midazolam, 1.35 (1.18-1.54); omeprazole, 0.81 (0.59-1.12); caffeine, 1.00 (0.77-1.30); and S-warfarin, 0.93 (0.84-1.03). The geometric least-squares (LS) mean ratio of urine dextromethorphan:dextrorphan ranged from 1.33 (0-4-h interval) to 1.64 (4-8-h interval). The data suggest that pazopanib is a weak inhibitor of CYP3A4 and CYP2D6 and has no effect on CYP1A2, CYP2C9, and CYP2C19 in patients with advanced cancer.

Delta sleep-inducing peptide and glucocorticoid-induced leucine zipper: potential links between circadian mechanisms and obesity?

As the obesity pandemic has accelerated, investigators have begun to explore alternative mechanisms linking circadian biology and sleep to adipose tissue metabolism and obesity. This manuscript reviews recent findings in murine and human models demonstrating the oscillatory expression of the mRNAs encoding the core circadian regulatory proteins in adipose tissue. Comparative transcriptomic analyses of circadian oscillating genes have been used to identify the 'delta sleep-inducing peptide immunoreactor', also known as 'glucocorticoid-induced leucine zipper (GILZ)', as a potential link in this chain. The GILZ gene has been found to differentially regulate stromal stem cell adipogenic and osteogenic differentiation in a reciprocal manner. In adipose and other metabolically active tissues, the circadian oscillation of GILZ expression is subject to entrainment by external stimuli. Together, these observations suggest that GILZ is an attractive candidate for future studies evaluating the role of circadian mechanisms in adipose tissue physiology and pathology.

Expression profile of mRNAs encoding core circadian regulatory proteins in human subcutaneous adipose tissue: correlation with age and body mass index

Objective

Circadian mechanisms underlie the physiology of mammals as an adaptation to the earth’s rotation on its axis. Highly conserved core circadian regulatory proteins (CCRP) maintain an oscillatory expression profile in the central and peripheral tissues. The CCRP include both a positive and negative arm as well as downstream transcriptional regulators. Recent studies in murine models have determined that the mRNAs encoding the CCRP are present in multiple adipose tissue depots and exhibit a robust oscillatory expression profile. The current study set out to examine the expression of CCRP mRNAs in human subcutaneous adipose tissues.

Design

Retrospective analysis of total RNA isolated from subcutaneous adipose tissue.

Subjects

150 healthy female and male lean (BMI < 25), overweight (BMI between 25 and 29.99) or obese (BMI >30) subjects of varied ethnic backgrounds undergoing elective liposuction or surgical procedures.

Results

The expression of the CCRP mRNAs displayed a significant correlation between each other and mRNAs representative of adipogenic biomarkers. Hierarchical cluster analyses of mRNAs isolated from the cohort of female Caucasian subjects (n = 116) identified three major clusters based on expression of downstream CCRP mRNAs. The mRNAs encoding D site of albumin promoter binding protein (DBP), E4 promoter binding protein 4 (E4BP4), PPARγ Co-Activator 1β (PGC-1β), and Rev-erb α were negatively correlated with BMI in a lean cluster (n = 66), positively correlated with BMI in a younger overweight/obese cluster (n = 19), and not significantly correlated with BMI in an older, overweight/obese cluster (n = 31).

Conclusions

These data confirm and extend findings that link the CCRP and circadian mechanisms to the risk of obesity.

PXR, CAR and HNF4alpha genotypes and their association with pharmacokinetics and pharmacodynamics of docetaxel and doxorubicin in Asian patients

Previously studied candidate genes have failed to account for inter-individual variability of docetaxel and doxorubicin disposition and effects. We genotyped the transcriptional regulators of CYP3A and ABCB1 in 101 breast cancer patients from 3 Asian ethnic groups, that is, Chinese, Malays and Indians, in correlation with the pharmacokinetics and pharmacodynamics of docetaxel and doxorubicin. While there was no ethnic difference in docetaxel and doxorubicin pharmacokinetics, ethnic difference in docetaxel- (ANOVA, P=0.001) and doxorubicin-induced (ANOVA, P=0.003) leukocyte suppression was observed, with Chinese and Indians experiencing greater degree of docetaxel-induced myelosuppression than Malays (Bonferroni, P=0.002, P=0.042), and Chinese experiencing greater degree of doxorubicin-induced myelosuppression than Malays and Indians (post hoc Bonferroni, P=0.024 and 0.025). Genotyping revealed both PXR and CAR to be well conserved; only a PXR 5'-untranslated region polymorphism (-24381A>C) and a silent CAR variant (Pro180Pro) were found at allele frequencies of 26 and 53%, respectively. Two non-synonymous variants were identified in HNF4alpha (Met49Val and Thr130Ile) at allele frequencies of 55 and 1%, respectively, with the Met49Val variant associated with slower neutrophil recovery in docetaxel-treated patients (ANOVA, P=0.046). Interactions were observed between HNF4alpha Met49Val and CAR Pro180Pro, with patients who were wild type for both variants experiencing least docetaxel-induced neutropenia (ANOVA, P=0.030). No other significant genotypic associations with pharmacokinetics or pharmacodynamics of either drug were found. The PXR-24381A>C variants were significantly more common in Indians compared to Chinese or Malays (32/18/21%, P=0.035) Inter-individual and inter-ethnic variations of docetaxel and doxorubicin pharmacokinetics or pharmacodynamics exist, but genotypic variability of the transcriptional regulators PAR, CAR and HNF4alpha cannot account for this variability.

Influence of UGT1A9 intronic I399C>T polymorphism on SN-38 glucuronidation in Asian cancer patients

Genetic polymorphisms in hepatically expressed UGT1A1 and UGT1A9 contribute to the interindividual variability i-n irinotecan disposition and toxicity. We screened UGT1A1 (UGT1A1*60, g.-3140G>A, UGT1A1*28 and UGT1A1*6) and UGT1A9 (g.-118(T)(9>10) and I399C>T) genes for polymorphic variants in the promoter and coding regions, and the genotypic effect of UGT1A9 I399C>T polymorphism on irinotecan disposition in Asian cancer patients was investigated. Blood samples were collected from 45 patients after administration of irinotecan as a 90 min intravenous infusion of 375 mg/m(2) once in every 3 weeks. Genotypic-phenotypic correlates showed that cancer patients heterozygous or homozygous for the I399C>T allele had approximately 2-fold lower systemic exposure to SN-38 (P<0.05) and a trend towards a higher relative extent of glucuronidation (REG) of SN-38 (P>0.05). UGT1A1-1A9 diplotype analysis showed that patients harbouring the H1/H2 (TG6GT(10)T/GG6GT(9)C) diplotype had 2.4-fold lower systemic exposure to SN-38 glucuronide (SN-38G) compared with patients harbouring the H1/H5 (TG6GT(10)T/GG6GT(10)C) diplotype (P=0.025). In conclusion, this in vivo study supports the in vitro findings of Girard et al. and suggests that the UGT1A9 I399C>T variant may be an important glucuronidating allele affecting the pharmacokinetics of SN-38 and SN-38G in Asian cancer patients receiving irinotecan chemotherapy.

Paclitaxel, 5-fluorouracil and hydroxyurea concurrent with radiation in locally advanced nasopharyngeal carcinoma

BACKGROUND

Concurrent chemoradiotherapy (CRT) is the standard treatment for locally advanced nasopharyngeal carcinoma (NPC). We conducted a phase II trial using paclitaxel, 5-fluorouracil and hydroxyurea concurrent with radiation (TFHX).

PATIENTS AND METHODS

Fifty-nine patients with locally advanced NPC were treated with CRT consisting of 4-day continuous infusions of paclitaxel (20 mg/m(2)/d) and 5-fluorouracil (600 mg/m(2)/d), and oral hydroxyurea 500 mg bid for nine doses, every 3 weeks concurrent with radiotherapy (RT). RT consisted of once daily 200cGy fractions 5 times per week to a total of 7000cGy.

RESULTS

Complete response was seen in 86% and 71% of patients at 4 and 12 months after CRT. The median follow-up was 34 months. Twenty-three patients experienced relapse. Sixteen deaths occurred: 13 from progressive disease. Three-year overall survival and progression-free survival were 72% and 54% respectively, with locoregional and distant control rates of 83% and 64% at 3 years respectively. Grade 3 to 4 acute toxicities included oropharyngeal mucositis in 81% of patients treated, dermatitis in 63%, weight loss in 32%, and neutropenia in 22%. Neutropenic fever was seen in 14%. There were no treatment-related deaths from acute toxicity.

CONCLUSIONS

TFHX is shown to be feasible in NPC. Non-cross resistant induction chemotherapy should be further studied with this regimen.