Superiority of concomitant chemoradiation over sequential chemoradiation in inoperable, locally advanced non-small cell lung cancer: challenges in the selection of appropriate chemotherapy

Poriaic Acid Affecting Epithelial-Mesenchymal Transition and Apoptosis of A549/DDP Cells via Glycogen Synthesis Kinase-3β/Snail Signaling Pathway

Background: The paper explored the mechanism of Poriaic acid-containing serum interfering with EMT and apoptosis of A549/DDP cells. The aim is to find experimental evidence of Poriaic acid intervening cisplatin resistance in lung cancer, searching for effective targets, and to explore the mechanism of cisplatin resistance in lung cancer. Material and methods: Immunochemistry and western blotting were employed to detect the effects of Poriaic acid-containing serum on the expressions of p-GSK-3β (ser9), Snail protein and mRNA in GSK-3β/Snail signaling pathway, and the effects of Poriaic acid-containing serum on the expressions of EMT markers and related apop-totic factors. Results: The results of immunoblotting and immunocytochemistry rendered that the expressions of p-GSK-3β (ser9), Snail protein and mRNA decreased in the administration group as contrast to the blank group. As to the effect of Poriaic acid-containing serum on EMT markers, the immunoblotting results showed that the E-cadherin protein and mRNA expressions increased while the expressions of N-cadherin protein and mRNA decreased. Poriaic acid-containing serum can up-regulate the expressions of P53, Bax protein and mRNA, and down-regulate the expressions of Bcl-2 protein and mRNA. Conclusion: Poriaic acid-containing serum can affect EMT and apoptosis of A549/DDP cells by interfering with GSK-3β/Snail signaling pathway.

Efficacy and safety of concurrent chemoradiotherapy in ECOG 2 patients with locally advanced non-small-cell lung cancer: a subgroup analysis of a randomized phase III trial

BACKGROUND

There is no consensus on the therapeutic approach to ECOG 2 patients with locally advanced non-small-cell lung cancer (LA-NSCLC), despite the sizable percentage of these patients in clinical practice. This study focused on the efficacy, toxicity and the optimal chemotherapy regimen of CCRT in ECOG 2 patients in a phase III trial.

METHODS

Patients capable of all self-care with bed rest for less than 50% of daytime were classified as ECOG 2 subgroup. A subgroup analysis was performed for ECOG 2 patients recruited in the phase III trial receiving concurrent EP (etoposide + cisplatin)/PC (paclitaxel + carboplatin) chemotherapy with intensity-modulated radiation therapy (IMRT) or three-dimensional conformal external beam radiation therapy (3D-CRT).

RESULTS

A total of 71 ECOG 2 patients were enrolled into the study. Forty-six (64.8%) patients were treated with IMRT technique. The median overall survival (OS) and progression free survival (PFS) for ECOG 2 patients were 16.4 months and 9 months, respectively. No difference was observed in treatment compliance and toxicities between ECOG 2 patients and ECOG 0-1 patients. Within the ECOG 2 group (31 in the EP arm and 40 in the PC arm), median OS and 3-year OS were 15.7 months and 37.5% for the EP arm, and 16.8 months and 7.5% for the PC arm, respectively (p = 0.243). The incidence of grade ≥ 3 radiation pneumonitis was higher in the PC arm (17.5% vs. 0.0%, p = 0.014) with 5 radiation pneumonitis related deaths, while the incidence of grade 3 esophagitis was numerically higher in the EP arm (25.8% vs. 10.0%, p = 0.078).

CONCLUSIONS

CCRT provided ECOG 2 patients promising outcome with acceptable toxicities. EP might be superior to PC in terms of safety profile in the setting of CCRT for ECOG 2 patients. Prospective randomized studies based on IMRT technique are warranted to validate our findings.

TRIAL REGISTRATION

ClinicalTrials.gov registration number: NCT01494558. (Registered 19 December 2011).

Effect of Concurrent Chemoradiation With Celecoxib vs Concurrent Chemoradiation Alone on Survival Among Patients With Non-Small Cell Lung Cancer With and Without Cyclooxygenase 2 Genetic Variants: A Phase 2 Randomized Clinical Trial

IMPORTANCE

Treatment of locally advanced non-small cell lung cancer (NSCLC) remains challenging. The rationale of combining a cyclooxygenase 2 (COX-2) inhibitor with concurrent chemoradiation (CCRT) was based on results of preclinical research and prospective clinical studies; however, no randomized clinical trial has provided evidence of a direct comparison with CCRT alone.

OBJECTIVE

To determine the effect of combined selective COX-2 inhibition with standard CCRT on survival among patients with unresectable stage III NSCLC.

DESIGN, SETTING, AND PARTICIPANTS

A single-center, open-label, randomized phase 2 clinical trial was performed among 96 patients who had histologically and cytologically confirmed unresectable stage III NSCLC. Participants were enrolled from November 2011 to August 2015. Data were analyzed from February to October 2018.

INTERVENTION

Patients were randomized to receive thoracic radiation, 60 Gy, for 6 weeks concurrent with etoposide and cisplatin or the same regimen of CCRT combined with 200 mg of celecoxib, taken twice daily.

MAIN OUTCOMES AND MEASURES

The primary end point was overall survival. The secondary end points were the proportion of patients with treatment-related toxic effects, progression-free survival, and overall survival in subgroups with and without the COX-2 genotype.

RESULTS

A total of 100 patients were randomized. Following the exclusion of 4 outliers, 96 participants (96.0%) were analyzed (51 randomized to CCRT alone and 45 randomized to CCRT with celecoxib; mean [SD] age, 60.0 [8.3] years; 73.0 [76.0%] male). The median overall survival time was 32.8 (95% CI, 17.0-48.5) months in the group that received CCRT with celecoxib and 35.5 (95% CI, 25.8-45.2) months in the group that received CCRT alone (P = .88). Celecoxib with CCRT was well tolerated; the incidence of symptomatic radiation pneumonitis was 6.6% (95% CI, 1.4%-18.0%) in the group that received CCRT with celecoxib and 11.8% (95% CI, 4.4%-23.9%) in the group that received CCRT alone (P = .49). Among patients with the high-risk genotype, celecoxib plus CCRT was not associated with higher progression-free survival (hazard ratio, 0.36; 95% CI, 0.13-1.04; P = .05) or overall survival (hazard ratio, 0.50; 95% CI, 0.15-1.72; P = .26) compared with CCRT alone.

CONCLUSIONS AND RELEVANCE

In unresectable stage III NSCLC, adding celecoxib to concurrent chemoradiation did not improve survival. A smaller, not statistically significant proportion of patients in the CCRT with celecoxib group compared with the CCRT alone group developed symptomatic radiation pneumonitis. Among patients with the high-risk genotype, adding celecoxib to CCRT did not improve overall or progression-free survival.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01503385.

Abemaciclib, a Selective CDK4/6 Inhibitor, Enhances the Radiosensitivity of Non-Small Cell Lung Cancer In Vitro and In Vivo

Purpose: To characterize the ionizing radiation (IR) enhancing effects and underlying mechanisms of the CDK4/6 inhibitor abemaciclib in non-small cell lung cancer (NSCLC) cells in vitro and in vivoExperimental Design: IR enhancement by abemaciclib in a variety of NSCLC cell lines was assessed by in vitro clonogenic assay, flow cytometry, and target inhibition verified by immunoblotting. IR-induced DNA damage repair was evaluated by γH2AX analysis. Global metabolic alterations by abemaciclib and IR combination were evaluated by LC/MS mass spectrometry and YSI bioanalyzer. Effects of abemaciclib and IR combination in vivo were studied by xenograft tumor regrowth delay, xenograft lysate immunoblotting, and tissue section immunohistochemistry.Results: Abemaciclib enhanced the radiosensitivity of NSCLC cells independent of RAS or EGFR status. Enhancement of radiosensitivity was lost in cell lines deficient for functional p53 and RB protein. After IR, abemaciclib treatment inhibited DNA damage repair as measured by γH2AX. Mechanistically, abemaciclib inhibited RB phosphorylation, leading to cell-cycle arrest. It also inhibited mTOR signaling and reduced intracellular amino acid pools, causing nutrient stress. In vivo, abemaciclib, when administered in an adjuvant setting for the second week after fractionated IR, further inhibited vasculogenesis and tumor regrowth, with sustained inhibition of RB/E2F activity, mTOR pathway, and HIF-1 expression. In summary, our study signifies inhibiting the CDK4/6 pathway by abemaciclib in combination with IR as a promising therapeutic strategy to treat NSCLC.Conclusions: Abemaciclib in combination with IR enhances NSCLC radiosensitivity in preclinical models, potentially providing a novel biomarker-driven combination therapeutic strategy for patients with NSCLC. Clin Cancer Res; 24(16); 3994-4005. ©2018 AACR.

Mutant KRAS associated malic enzyme 1 expression is a predictive marker for radiation therapy response in non-small cell lung cancer

Background

Advanced non-small cell lung cancer (NSCLC) is an aggressive tumor that is treated with a combination of chemotherapy and radiation if the patient is not a candidate for surgery. Predictive biomarkers for response to radiotherapy are lacking in this patient population, making it a non-tailored therapy regimen with unknown outcome. Twenty to 30 % of NSCLC harbor an activating mutation in KRAS that may confer radioresistance. We hypothesized that mutant KRAS can regulate glutamine metabolism genes in NSCLC and maintain tumor redox balance through transamination reactions that generate cytosolic NADPH via malic enzyme 1 (ME1), which may contribute to radioresistance.

Findings

A doxycycline-inducible mouse model of KRAS^G12D driven NSCLC and patient data was analyzed from multiple publicly accessible databases including TCGA, CCLE, NCBI GEO and Project Achilles. ME1 expression was found to be mutant KRAS associated in both a NSCLC mouse model and human NSCLC cancer cell lines. Perturbing glutamine metabolism sensitized mutant KRAS, but not wild-type KRAS NSCLC cell lines to radiation treatment. NSCLC survival analysis revealed that patients with elevated ME1 and GOT1 expression had significantly worse outcomes after radiotherapy, but this was not seen after chemotherapy alone.

Conclusions

KRAS driven glutamine metabolism genes, specifically ME1 and GOT1 reactions, may be a predictive marker and potential therapeutic target for radiotherapy in NSCLC.

Electronic supplementary material

The online version of this article (doi:10.1186/s13014-015-0457-x) contains supplementary material, which is available to authorized users.