Antiangiogenic Therapy in Advanced Non-small-cell Lung Cancer: A Meta-analysis of Phase III Randomized Trials.

We conducted a meta-analysis to evaluate the efficacy of adding any antiangiogenic therapy (AT) to the standard of care in advanced non-small-cell lung cancer (NSCLC). The electronic databases Ovid PubMed, Cochrane Central Register of Controlled Trials, and Embase were searched to identify eligible trials. We included all phase III randomized trials with any line and type of treatment, histology. and AT dose. Pooled hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS), and pooled odds ratio (OR) for overall response rates (RR) were calculated. We divided the population into 2 subgroups based on the bevacizumab dose. Data of 19,098 patients from 25 phase III trials were analyzed. Compared with the standard of care, the addition of AT did not prolong OS (HR 0.98; 95% confidence interval [CI], 0.96-1.00; P = .1 and HR 0.97; 95% CI, 0.94-1.00; P = .06 for groups 1 and 2, respectively). However, there was a significant improvement in PFS with the addition of AT (HR 0.85; 95% CI, 0.79-0.91; P < .00001 and HR 0.81; 95% CI, 0.75-0.88; P < .00001 for groups 1 and 2, respectively) and overall RR (OR 1.61; 95% CI, 1.30-2.01; P < .0001 and OR 1.72; 95% CI, 1.39-2.14; P < .00001 for groups 1 and 2, respectively). This is the first meta-analysis including only all phase III trials with AT in NSCLC showing no significant effect on OS and an improvement in PFS and RR only. The role of AT in advanced NSCLC is still questionable; strong validated biomarkers are eagerly needed to predict which subgroup might benefit the most from such therapy.

A systematic literature analysis of correlative studies in low-dose metronomic chemotherapy trials.

Low-dose metronomic (LDM) chemotherapy is a beneficial and very well-tolerated form of chemotherapy utilization characterized by the frequent and uninterrupted administration of low doses of conventional chemotherapeutic agents over prolonged periods of time. While patients resistant to standard maximum tolerated dose (MTD) chemotherapy may still benefit from LDM chemotherapy, there is a lack of predictive markers of response to LDM chemotherapy. We searched the MEDLINE, EMBASE, CENTRAL and PubMed databases for correlative studies conducted as part of LDM chemotherapy trials in order to identify the most promising biomarker candidates. Given the antiangiogenic properties of LDM chemotherapy, angiogenesis-related biomarkers were most commonly studied. However, significant correlations between angiogenesis-related biomarkers and study end points were rare and variable, even so far as biomarkers correlating positively with an end point in some studies and negatively with the same end point in other studies. Pursuing biomarkers outside the angiogenesis field may be more promising.

FGF23: mediator of poor prognosis in a sizeable subgroup of patients with castration-resistant prostate cancer presenting with severe hypophosphatemia?

Castration-resistant prostate cancer (CRPC) is an advanced and incurable stage of the second most frequently diagnosed malignancy in men globally. Current treatment options improve survival modestly but eventually fail due to intrinsic or acquired therapeutic resistance. A hypothesis is presented wherein circulating levels of fibroblast growth factor 23 (FGF23), an endocrine member of the fibroblast growth factor family with phosphaturic properties, are proposed as a prognostic and predictive marker to identify CRPC patients with poor prognosis that are amenable to FGF23 antibody therapy (FGF23i) or treatment with fibroblast growth factor receptor inhibitors (FGFRi). With respect to the latter, FGF23 may also serve as a pharmacodynamic marker enabling individualized FGFRi dosing. We recently discovered that the development of severe and sustained hypophosphatemia in CRPC patients undergoing zoledronic acid therapy for bone metastases was associated with markedly worse prognosis compared to patients without or with only mild and transient hypophosphatemia. Severe hypophosphatemia is a typical manifestation of tumor-induced hypophosphatemic osteomalacia (TIO), a paraneoplastic condition mediated by FGF23 overexpression in most instances. While the postulated tumor-promoting role of FGF23 in CRPC or other malignancies has not yet been studied, several lines of evidence suggest that FGF23 may mediate both severe hypophosphatemia (via its endocrine properties) and aggressive CRPC behavior (via autocrine and paracrine activities): (i) FGF23 and the necessary signalling machinery (i.e. members of the fibroblast growth factor receptor [FGFR] family and the essential co-receptor α-KLOTHO [KL]) are highly expressed in a sizeable subgroup of CRPC patients; (ii) FGF/FGFR signalling plays important roles in prostate cancer; (iii) FGF23 can induce its own expression via a positive autocrine feedback loop involving FGFR1; and (iv) this positive feedback loop may be triggered by bone-targeted therapies frequently used for the treatment of CRPC-associated bone metastases. While there is a lack of personalized treatment strategies in the management of CRPC to date, FGF23 targeted therapy has the potential to fill this unmet clinical need in the not-so-distant future. In fact, FGFRi are currently in advanced clinical testing for a number of malignancies such as kidney and lung cancer, but there is a lack of conclusive data on FGFRi therapy in patients selected for FGF/FGFR pathway activation.