Melanoma patients in a phase I clinic: molecular aberrations, targeted therapy and outcomes

Polysaccharide hydrogels regulate macrophage polarization and enhance the anti-tumor efficacy of melanoma

Chemotherapy occupies a prominent position in combination treatments of melanoma. However, the severe systemic side effects and the pro-tumorigenic microenvironment limited its therapeutic efficacy. In the present study, polysaccharide hydrogels (SCOD) were constructed by N-succinyl chitosan and oxidized dextran through Schiff-base formation to deliver doxorubicin (Dox) locally. The gelation time and mechanical properties of SCOD hydrogels could be fine-tuned by varying concentration of precursor solutions. Rheological data revealed that SCOD hydrogels possessed injectable shear-shinning property and remarkable self-healing capability. It also could be degraded by lysozyme widely present in body fluids. Moreover, SCOD hydrogels were readily loaded with Dox in precursor solutions and released drug over 1 week in a pH-dependent manner. The ability of Dox-loaded SCOD hydrogels to inhibit the growth of murine B16 and human A375 melanoma was verified by in vitro assays. Strikingly, Dox-loaded SCOD hydrogels were found to efficiently induce polarization of tumor-associated macrophages towards M1 phenotype that favors an anti-tumorigenic tumor microenvironment. Notably, in vivo experiments demonstrated that locally injected Dox-loaded SCOD hydrogels exhibited excellent anti-tumor activity against B16 melanoma, outperforming Dox at equivalent doses administrated intravenously. Therefore, the injectable and self-healing polysaccharide hydrogels are a promising strategy to improve locoregional control in melanoma.

Value-based genomics

Advancements in next-generation sequencing have greatly enhanced the development of biomarker-driven cancer therapies. The affordability and availability of next-generation sequencers have allowed for the commercialization of next-generation sequencing platforms that have found widespread use for clinical-decision making and research purposes. Despite the greater availability of tumor molecular profiling by next-generation sequencing at our doorsteps, the achievement of value-based care, or improving patient outcomes while reducing overall costs or risks, in the era of precision oncology remains a looming challenge. In this review, we highlight available data through a pre-established and conceptualized framework for evaluating value-based medicine to assess the cost (efficiency), clinical benefit (effectiveness), and toxicity (safety) of genomic profiling in cancer care. We also provide perspectives on future directions of next-generation sequencing from targeted panels to whole-exome or whole-genome sequencing and describe potential strategies needed to attain value-based genomics.

Universal Genomic Testing: The next step in oncological decision-making or a dead end street?

The concept of 'personalised medicine' aims at allocating patients to different treatment options based on individual characteristics to optimise treatment benefit and side effects. In oncology, personalised treatments coupled to biomarkers have led to the approval of targeted agents with high anti-tumour activity. However, these therapies are often limited to narrow, molecularly defined subsets of patients with a specific morphomolecular tumour profile. Recently, it became obvious that the same molecular alteration might drive oncogenesis in many different tumours, and it might be beneficial to target the alteration in a histology informed but entity-overarching way. Consequently, Universal Genomic Testing (UGT) of tumours encompassing panel sequencing to whole-exome and transcriptome sequencing is propagated to revolutionise oncology. This article will describe the developments leading to identification and application of potential biomarkers using UGT. On this basis, it will review the clinical evidence of this approach and summarise recommendations for the ongoing evaluation of UGT as the next step in oncological decision-making.

The Conundrum of Genetic "Drivers" in Benign Conditions

Advances in deep genomic sequencing have identified a spectrum of cancer-specific passenger and driver aberrations. Clones with driver anomalies are believed to be positively selected during carcinogenesis. Accumulating evidence, however, shows that genomic alterations, such as those in BRAF, RAS, EGFR, HER2, FGFR3, PIK3CA, TP53, CDKN2A, and NF1/2, all of which are considered hallmark drivers of specific cancers, can also be identified in benign and premalignant conditions, occasionally at frequencies higher than in their malignant counterparts. Targeting these genomic drivers can produce dramatic responses in advanced cancer, but the effects on their benign counterparts are less clear. This benign-malignant phenomenon is well illustrated in studies of BRAF V600E mutations, which are paradoxically more frequent in benign nevi (∼80%) than in dysplastic nevi (∼60%) or melanoma (∼40%-45%). Similarly, human epidermal growth factor receptor 2 is more commonly overexpressed in ductal carcinoma in situ (∼27%-56%) when compared with invasive breast cancer (∼11%-20%). FGFR3 mutations in bladder cancer also decrease with tumor grade (low-grade tumors, ∼61%; high-grade, ∼11%). “Driver” mutations also occur in nonmalignant settings: TP53 mutations in synovial tissue from rheumatoid arthritis and FGFR3 mutations in seborrheic keratosis. The latter observations suggest that the oncogenicity of these alterations may be tissue context–dependent. The conversion of benign conditions to premalignant disease may involve other genetic events and/or epigenetic reprogramming. Putative driver mutations can also be germline and associated with increased cancer risk (eg, germline RAS or TP53 alterations), but germline FGFR3 or NF2 abnormalities do not predispose to malignancy. We discuss the enigma of genetic “drivers” in benign and premalignant conditions and the implications for prevention strategies and theories of tumorigenesis.

Genomically Driven Tumors and Actionability across Histologies: BRAF-Mutant Cancers as a Paradigm

The diagnosis, classification, and management of cancer are traditionally dictated by the site of tumor origin, for example, breast or lung, and by specific histologic subtypes of site-of-origin cancers (e.g., non-small cell versus small cell lung cancer). However, with the advent of sequencing technologies allowing for rapid, low cost, and accurate sequencing of clinical samples, new observations suggest an expanded or different approach to the diagnosis and treatment of cancer-one driven by the unique molecular features of the tumor. We discuss a genomically driven strategy for cancer treatment using BRAF as an example. Several key points are highlighted: (i) molecular aberrations can be shared across cancers; (ii) approximately 15% of all cancers harbor BRAF mutations; and (iii) BRAF inhibitors, while approved only for melanoma, have reported activity across numerous cancers and related disease types bearing BRAF aberrations. However, BRAF-mutated colorectal cancer has shown poor response rate to BRAF inhibitor monotherapy, striking a cautionary note. Yet, even in this case, emerging data suggest BRAF-mutated colorectal cancers can respond well to BRAF inhibitors, albeit when administered in combination with other agents that impact resistance pathways. Taken together, these data suggest that molecular aberrations may be the basis for a new nosology for cancer. Mol Cancer Ther; 15(4); 533-47. ©2016 AACR.

Impact of a Biomarker-Based Strategy on Oncology Drug Development: A Meta-analysis of Clinical Trials Leading to FDA Approval

BACKGROUND

In order to ascertain the impact of a biomarker-based (personalized) strategy, we compared outcomes between US Food and Drug Administration (FDA)-approved cancer treatments that were studied with and without such a selection rationale.

METHODS

Anticancer agents newly approved (September 1998 to June 2013) were identified at the Drugs@FDA website. Efficacy, treatment-related mortality, and hazard ratios (HRs) for time-to-event endpoints were analyzed and compared in registration trials for these agents. All statistical tests were two-sided.

RESULTS

Fifty-eight drugs were included (leading to 57 randomized [32% personalized] and 55 nonrandomized trials [47% personalized], n = 38 104 patients). Trials adopting a personalized strategy more often included targeted (100% vs 65%, P < .001), oral (68% vs 35%, P = .001), and single agents (89% vs 71%, P = .04) and more frequently permitted crossover to experimental treatment (67% vs 28%, P = .009). In randomized registration trials (using a random-effects meta-analysis), personalized therapy arms were associated with higher relative response rate ratios (RRRs, compared with their corresponding control arms) (RRRs = 3.82, 95% confidence interval [CI] = 2.51 to 5.82, vs RRRs = 2.08, 95% CI = 1.76 to 2.47, adjusted P = .03), longer PFS (hazard ratio [HR] = 0.41, 95% CI = 0.33 to 0.51, vs HR = 0.59, 95% CI = 0.53 to 0.65, adjusted P < .001) and a non-statistically significantly longer OS (HR = 0.71, 95% CI = 0.61 to 0.83, vs HR = 0.81, 95% CI = 0.77 to 0.85, adjusted P = .07) compared with nonpersonalized trials. Analysis of experimental arms in all 112 registration trials (randomized and nonrandomized) demonstrated that personalized therapy was associated with higher response rate (48%, 95% CI = 42% to 55%, vs 23%, 95% CI = 20% to 27%, P < .001) and longer PFS (median = 8.3, interquartile range [IQR] = 5 vs 5.5 months, IQR = 5, adjusted P = .002) and OS (median = 19.3, IQR = 17 vs 13.5 months, IQR = 8, Adjusted P = .04). A personalized strategy was an independent predictor of better RR, PFS, and OS, as demonstrated by multilinear regression analysis. Treatment-related mortality rate was similar for personalized and nonpersonalized trials.

CONCLUSIONS

A biomarker-based approach was safe and associated with improved efficacy outcomes in FDA-approved anticancer agents.

Impact of Precision Medicine in Diverse Cancers: A Meta-Analysis of Phase II Clinical Trials

PURPOSE

The impact of a personalized cancer treatment strategy (ie, matching patients with drugs based on specific biomarkers) is still a matter of debate.

METHODS

We reviewed phase II single-agent studies (570 studies; 32,149 patients) published between January 1, 2010, and December 31, 2012 (PubMed search). Response rate (RR), progression-free survival (PFS), and overall survival (OS) were compared for arms that used a personalized strategy versus those that did not.

RESULTS

Multivariable analysis (both weighted multiple linear regression and random effects meta-regression) demonstrated that the personalized approach, compared with a nonpersonalized approach, consistently and independently correlated with higher median RR (31% v 10.5%, respectively; P < .001) and prolonged median PFS (5.9 v 2.7 months, respectively; P < .001) and OS (13.7 v 8.9 months, respectively; P < .001). Nonpersonalized targeted arms had poorer outcomes compared with either personalized targeted therapy or cytotoxics, with median RR of 4%, 30%, and 11.9%, respectively; median PFS of 2.6, 6.9, and 3.3 months, respectively (all P < .001); and median OS of 8.7, 15.9, and 9.4 months, respectively (all P < .05). Personalized arms using a genomic biomarker had higher median RR and prolonged median PFS and OS (all P ≤ .05) compared with personalized arms using a protein biomarker. A personalized strategy was associated with a lower treatment-related death rate than a nonpersonalized strategy (median, 1.5% v 2.3%, respectively; P < .001).

CONCLUSION

Comprehensive analysis of phase II, single-agent arms revealed that, across malignancies, a personalized strategy was an independent predictor of better outcomes and fewer toxic deaths. In addition, nonpersonalized targeted therapies were associated with significantly poorer outcomes than cytotoxic agents, which in turn were worse than personalized targeted therapy.

Molecular aberrations, targeted therapy, and renal cell carcinoma: current state-of-the-art

Renal cell carcinoma (RCC) is among the most prevalent malignancies in the USA. Most RCCs are sporadic, but hereditary syndromes associated with RCC account for 2-3 % of cases and include von Hippel-Lindau, hereditary leiomyomatosis, Birt-Hogg-Dube, tuberous sclerosis, hereditary papillary RCC, and familial renal carcinoma. In the past decade, our understanding of the genetic mutations associated with sporadic forms of RCC has increased considerably, with the most common mutations in clear cell RCC seen in the VHL, PBRM1, BAP1, and SETD2 genes. Among these, BAP1 mutations are associated with aggressive disease and decreased survival. Several targeted therapies for advanced RCC have been approved and include sunitinib, sorafenib, pazopanib, axitinib (tyrosine kinase inhibitors (TKIs) with anti-vascular endothelial growth factor (VEGFR) activity), everolimus, and temsirolimus (TKIs that inhibit mTORC1, the downstream part of the PI3K/AKT/mTOR pathway). High-dose interleukin 2 (IL-2) immunotherapy and the combination of bevacizumab plus interferon-α are also approved treatments. At present, there are no predictive genetic markers to direct therapy for RCC, perhaps because the vast majority of trials have been evaluated in unselected patient populations, with advanced metastatic disease. This review will focus on our current understanding of the molecular genetics of RCC, and how this may inform therapeutics.

Unique molecular signatures as a hallmark of patients with metastatic breast cancer: implications for current treatment paradigms

Our analysis of the tumors of 57 women with metastatic breast cancer with next generation sequencing (NGS) demonstrates that each patient's tumor is unique in its molecular fingerprint. We observed 216 somatic aberrations in 70 different genes, including 131 distinct aberrations. The most common gene alterations (in order of decreasing frequency) included: TP53, PIK3CA, CCND1, MYC, HER2 (ERBB2), MCL1, PTEN, FGFR1, GATA3, NF1, PIK3R1, BRCA2, EGFR, IRS2, CDH1, CDKN2A, FGF19, FGF3 and FGF4. Aberrations included mutations (46%), amplifications (45%), deletions (5%), splices (2%), truncations (1%), fusions (0.5%) and rearrangements (0.5%), with multiple distinct variants within the same gene. Many of these aberrations represent druggable targets, either through direct pathway inhibition or through an associated pathway (via ‘crosstalk’). The ‘molecular individuality’ of these tumors suggests that a customized strategy, using an “N-of-One” model of precision medicine, may represent an optimal approach for the treatment of patients with advanced tumors.

Nras in melanoma: targeting the undruggable target

RAS belongs to the guanosine 5'-triphosphate (GTP)-binding proteins' family, and oncogenic mutations in codons 12, 13, or 61 of RAS family occur in approximately one third of all human cancers with N-RAS mutations found in about 15-20% of melanomas. The importance of RAS signaling as a potential target in cancer is emphasized not only by the prevalence of RAS mutations, but also by the high number of RAS activators and effectors identified in mammalian cells that places the RAS proteins at the crossroads of several, important signaling networks. Ras proteins are crucial crossroads of signaling pathways that link the activation of cell surface receptors with a wide variety of cellular processes leading to the control of proliferation, apoptosis and differentiation. Furthermore, oncogenic ras proteins interfere with metabolism of tumor cells, microenvironment's remodeling, evasion of the immune response, and finally contributes to the metastatic process. After 40 years of basic, translational and clinical research, much is now known about the molecular mechanisms by which these monomeric guanosine triphosphatase-binding proteins promote cellular malignancy, and it is clear that they regulate signaling pathways involved in the control of cell proliferation, survival, and invasiveness. In this review we summarize the biological role of RAS in cancer by focusing our attention on the biological rational and strategies to target RAS in melanoma.