Calls to action on lung cancer management and research.

Lung cancer, the leading cause of cancer-related deaths globally, remains a pressing health issue despite significant medical advances. The New York Lung Cancer Foundation brought together experts from academia, the pharmaceutical and biotech industries as well as organizational leaders and patient advocates, to thoroughly examine the current state of lung cancer diagnosis, treatment, and research. The goal was to identify areas where our understanding is incomplete and to develop collaborative public health and scientific strategies to generate better patient outcomes, as highlighted in our "Calls to Action." The consortium prioritized 8 different calls to action. These include (1) develop strategies to cure more patients with early-stage lung cancer, (2) investigate carcinogenesis leading to lung cancers in patients without a history of smoking, (3) harness precision medicine for disease interception and prevention, (4) implement solutions to deliver prevention measures and effective therapies to individuals in under-resourced countries, (5) facilitate collaborations with industry to collect and share data and samples, (6) create and maintain open access to big data repositories, (7) develop new immunotherapeutic agents for lung cancer treatment and prevention, and (8) invest in research in both the academic and community settings. These calls to action provide guidance to representatives from academia, the pharmaceutical and biotech industries, organizational and regulatory leaders, and patient advocates to guide ongoing and planned initiatives.

Genomic, immunologic, and prognostic associations of TROP2 (TACSTD2) expression in solid tumors.

BACKGROUND: TROP2 (TACSTD2) expression is associated with decreased overall survival (OS) in some solid tumors, and the TROP2-targeting antibody-drug conjugate (ADC) sacituzumab govitecan has been approved in breast and urothelial carcinomas. We aimed to explore the multi-omic landscape associated with TACSTD2 gene expression in various solid tumors to identify patients most likely to benefit from this approach. METHODS: Breast (N = 11 246), colorectal (N = 15 425), hepatocellular (N = 433), pancreatic (N = 5488), and urothelial (N = 4125) tumors were stratified into quartiles by TACSTD2 gene expression, analyzed by next-generation DNA sequencing, whole transcriptome sequencing, and immunohistochemistry at Caris Life Sciences (Phoenix, AZ). Survival data were obtained from insurance claims, and Kaplan-Meier estimates were calculated for molecularly defined cohorts. RESULTS: Several pathogenic mutations were associated with TACSTD2-high tumors, including TP53 in breast, colorectal (CRC), pancreatic, and hepatocellular cancers; KRAS in pancreatic and CRC cancers; ARID1A and FGFR3 in urothelial cancer; and CTNNB1 in hepatocellular cancer. TACSTD2-low breast tumors were enriched for copy number amplifications in CCND1 and FGF/R family member genes. TACSTD2 high was generally associated with more immune cell infiltration and greater T-cell inflammation scores. Patients with TACSTD2-high breast, CRC, and pancreatic cancers demonstrated a significantly shorter OS than TACSTD2-low tumors. This was restricted to CRC with microsatellite stable tumors and patients with pancreatic cancer with KRAS-mutant tumors. Patients with breast cancer with TACSTD2-high tumors also experienced significantly worse OS following immune checkpoint inhibitors. CONCLUSIONS: TACSTD2 expression is associated with key driver alterations and a more active immune microenvironment, suggesting possible combinatorial strategies with TROP2-targeting ADCs plus immunotherapy in various solid tumors.

Similar Efficacy Observed for First-Line Immunotherapy in Racial/Ethnic Minority Patients With Metastatic NSCLC.

BACKGROUND: Limited data exist on the impact of immunotherapy use in ethnic minority patients with non-small cell lung cancer (NSCLC), because they have been underrepresented in immunotherapy trials. This study aims to evaluate race/ethnicity and other demographic, socioeconomic, and clinical factors of patients with metastatic NSCLC treated with first-line immunotherapy. METHODS: A retrospective cohort study of 5,920 patients diagnosed with lung cancer treated at Montefiore Einstein Cancer Center from January 1, 2013, to June 1, 2022, was used to identify patients with metastatic NSCLC without EGFR, ALK, or ROS1 alterations who underwent first-line immunotherapy (n=248). The primary endpoint was overall survival (OS), with secondary endpoints of progression-free survival (PFS) and time to discontinuation (TTD) from the start of immunotherapy. RESULTS: Among the 248 patients, median follow-up time was 12.0 months, median age at start of treatment was 66 years, and 39.1% were non-Hispanic Black, 30.2% were Hispanic, and 30.7% were non-Hispanic White. OS (P=.39), PFS (P=.29), and TTD (P=.98) were similar among racial/ethnic groups. Patients with an ECOG performance status (PS) of <2 at the start of immunotherapy had longer OS compared with those with ECOG PS of ≥2 (P<.0001). PD-L1 expression (<50% vs ≥50%; P=.03) and body mass index (BMI) (P=.01) were also found to be associated with PFS, and ECOG PS (P<.0001) and BMI (P=.02) were associated with TTD. In a multivariate analysis of OS and PFS, ECOG PS was the only variable found to be significant. CONCLUSIONS: Our study observed similar benefits of immunotherapy in patients with metastatic NSCLC in different racial and ethnic groups. Furthermore, ECOG PS was associated with OS, and PD-L1 expression and BMI were associated with PFS and TTD. These findings help identify potential factors associated with outcomes and care while patients are undergoing immunotherapy.

Biomarker testing in cancer management- can one size fit all?

Biomarker-guided treatment selection has transformed cancer management. Pruis et al. provide a powerful example of the challenges and promises of whole genome sequencing to match patients with advanced cancer for precision oncology studies and targeted therapies. Expanding genomic testing platforms are reviewed with a view towards future applications to inform clinical cancer research and practice.

Do Patients Regret Having Received Systemic Treatment for Advanced Non-Small Cell Lung Cancer: A Prospective Evaluation.

BACKGROUND: Thousands of patients annually receive treatment for advanced non-small cell lung cancer (NSCLC), but little is known about their views on the decision to receive that treatment, or regret. This trial prospectively evaluated the incidence of regret and whether baseline characteristics, patient decision-making parameters, or clinical progress early in the treatment course predicts regret. MATERIALS AND METHODS: Patients receiving systemic treatment for advanced NSCLC completed every 3-week patient reported outcome (PRO) assessment using the electronic Lung Cancer Symptom Scale (eLCSS-QL), including the 3-Item Global Index (3-IGI; assessing overall distress, activities, and quality of life [QL]). A prespecified secondary aim was to determine the frequency of regret evaluated at 3 months after starting treatment. Patients were randomized to usual care or enhanced care (which included use of the DecisionKEYS decision aid). RESULTS: Of 164 patients entered, 160 received treatment and 142 were evaluable for regret. In total, 11.5% of patients and 9% of their supporters expressed regret. Baseline characteristics did not predict regret; regret was rarely expressed by those who had a less than 20% decline or improvement in the 3-IGI PRO score after two treatment cycles. In contrast, when asked if they would make the same decision again, only 1% not having a 20% 3-IGI decline expressed regret, versus 14% with a 3-IGI decline (p = .01). CONCLUSION: The majority of patients having regret were identified early using the PRO 3-IGI of the eLCSS-QL measure. Identifying patients at risk for regret allows for interventions, including frank discussions of progress and goals early in the treatment course, which could address regret in patients and their supporters. IMPLICATIONS FOR PRACTICE: This report documents prospectively, for the first time, the incidence of treatment-related regret in patients with advanced lung cancer and outlines that risk of regret is associated with patient-determined worsening health status early in the course of treatment. Identifying patients at risk for regret early in treatment (before the third cycle of treatment) appears to be crucial. Counseling at that time should include a discussion of consideration of treatment change and the reason for this change.

Pembrolizumab plus Chemotherapy for Squamous Non-Small-Cell Lung Cancer.

BACKGROUND: Standard first-line therapy for metastatic, squamous non-small-cell lung cancer (NSCLC) is platinum-based chemotherapy or pembrolizumab (for patients with programmed death ligand 1 [PD-L1] expression on ≥50% of tumor cells). More recently, pembrolizumab plus chemotherapy was shown to significantly prolong overall survival among patients with nonsquamous NSCLC. METHODS: In this double-blind, phase 3 trial, we randomly assigned, in a 1:1 ratio, 559 patients with untreated metastatic, squamous NSCLC to receive 200 mg of pembrolizumab or saline placebo for up to 35 cycles; all the patients also received carboplatin and either paclitaxel or nanoparticle albumin-bound [nab]-paclitaxel for the first 4 cycles. Primary end points were overall survival and progression-free survival. RESULTS: After a median follow-up of 7.8 months, the median overall survival was 15.9 months (95% confidence interval [CI], 13.2 to not reached) in the pembrolizumab-combination group and 11.3 months (95% CI, 9.5 to 14.8) in the placebo-combination group (hazard ratio for death, 0.64; 95% CI, 0.49 to 0.85; P<0.001). The overall survival benefit was consistent regardless of the level of PD-L1 expression. The median progression-free survival was 6.4 months (95% CI, 6.2 to 8.3) in the pembrolizumab-combination group and 4.8 months (95% CI, 4.3 to 5.7) in the placebo-combination group (hazard ratio for disease progression or death, 0.56; 95% CI, 0.45 to 0.70; P<0.001). Adverse events of grade 3 or higher occurred in 69.8% of the patients in the pembrolizumab-combination group and in 68.2% of the patients in the placebo-combination group. Discontinuation of treatment because of adverse events was more frequent in the pembrolizumab-combination group than in the placebo-combination group (13.3% vs. 6.4%). CONCLUSIONS: In patients with previously untreated metastatic, squamous NSCLC, the addition of pembrolizumab to chemotherapy with carboplatin plus paclitaxel or nab-paclitaxel resulted in significantly longer overall survival and progression-free survival than chemotherapy alone. (Funded by Merck Sharp & Dohme; KEYNOTE-407 ClinicalTrials.gov number, NCT02775435 .).

Pembrolizumab plus chemotherapy versus chemotherapy alone in patients with advanced non-small cell lung cancer without tumor PD-L1 expression: A pooled analysis of 3 randomized controlled trials.

BACKGROUND: Pembrolizumab plus platinum-based chemotherapy has demonstrated improved clinical outcomes over chemotherapy alone in patients with previously untreated advanced/metastatic non-small cell lung cancer (NSCLC), regardless of tumor programmed death ligand 1 (PD-L1) expression. This study pooled data from 3 randomized controlled trials to evaluate outcomes with pembrolizumab plus chemotherapy versus chemotherapy alone in patients with advanced/metastatic NSCLC negative for PD-L1 (ie, a tumor proportion score < 1%). METHODS: Individual patient data were pooled from KEYNOTE-021 cohort G (nonsquamous; NCT02039674), KEYNOTE-189 (nonsquamous; NCT02578680 and NCT03950674), and KEYNOTE-407 (squamous; NCT02775435). Treatment comprised pembrolizumab plus chemotherapy (pemetrexed and platinum for nonsquamous histology and carboplatin and paclitaxel/nab-paclitaxel for squamous histology) or chemotherapy alone. Responses were assessed according to Response Evaluation Criteria in Solid Tumors version 1.1 by blinded, independent, central review. No α was assigned to this descriptive, exploratory analysis. RESULTS: Four hundred forty-four of the 1328 patients (33.4%) who were enrolled across the 3 trials had PD-L1-negative tumors (256 on pembrolizumab plus chemotherapy [nonsquamous, n = 155; squamous, n = 94; other, n = 7] and 188 on chemotherapy alone [nonsquamous, n = 83; squamous, n = 99; other, n = 6]). The median time from randomization to the data cutoff was 28.0 months (range, 14.7-55.4 months). Pembrolizumab plus chemotherapy improved overall survival (OS; hazard ratio [HR], 0.63; 95% CI, 0.50-0.79) and progression-free survival (HR, 0.68; 95% CI, 0.56-0.83) over chemotherapy. Sixteen patients in the pembrolizumab plus chemotherapy arm completed 2 years of treatment; the objective response rate was 87.5% (95% CI, 61.7%-98.4%), and the 3-year OS rate was 100%. Adverse events (AEs) were experienced by 99.2% of the patients who received pembrolizumab plus chemotherapy and by 98.9% of the patients who received chemotherapy alone, with grade 3 or higher AEs occurring in 71.4% and 72.0%, respectively; immune-mediated AEs and infusion reactions were experienced by 29.0% and 12.4%, respectively. CONCLUSIONS: Pembrolizumab plus chemotherapy demonstrated response and survival improvements with manageable safety in comparison with chemotherapy alone in PD-L1-negative advanced/metastatic NSCLC, and it is a standard-of-care first-line therapy for patients with advanced NSCLC, regardless of PD-L1 expression. LAY SUMMARY: Some tumors produce a protein called programmed death ligand 1 (PD-L1), which interacts with the body's immune system and prevents an immune response against cancer. Antibody therapies such as pembrolizumab block interactions between tumor PD-L1 and the immune system and enable an immune response. Used alone, pembrolizumab provides benefit for patients with non-small cell lung cancer (NSCLC) tumors that produce PD-L1. However, when it is combined with chemotherapy, which can stimulate anticancer immune responses, pembrolizumab provides a benefit, regardless of tumor PD-L1 production. This article shows that among patients with NSCLC whose tumors produce no PD-L1, outcomes are better with pembrolizumab plus chemotherapy in comparison with chemotherapy alone.

INI-1 (SMARCB1)-Deficient Undifferentiated Sinonasal Carcinoma: Novel Paradigm of Molecular Testing in the Diagnosis and Management of Sinonasal Malignancies.

Sinonasal tumors consist of a group of rare heterogeneous malignancies, accounting for 3%-5% of all head and neck cancers. Although squamous cell carcinomas make up a significant portion of cancers arising in the sinonasal tract, there are a variety of aggressive tumor types that can present with a poorly differentiated morphology and continue to pose diagnostic challenges. Accurate classification of these unique malignancies has treatment implications for patients. Recent discoveries have allowed more detailed molecular characterization of subsets of these tumor types, and may lead to individualized treatments. INI-1 (SMARCB1)-deficient sinonasal carcinoma is a recently identified subtype of sinonasal malignancy, which is characterized by deletion of the INI-1 tumor suppressor gene. Loss of INI-1 expression has emerged as an important diagnostic feature in several human malignancies including a subset of sinonasal carcinomas. In this article, we present a case of INI-1 (SMARCB1)-deficient sinonasal carcinoma, provide an overview of recent advances in histological and molecular classification of sinonasal malignancies, and discuss challenges of caring for patients with these rare malignancies, as well as potential treatment implications. KEY POINTS: Clinicians and pathologists should recognize that a variety of sinonasal tumors can present with a poorly differentiated morphology that warrants further workup and molecular classification. Routine workup of poorly or undifferentiated sinonasal tumors should include testing for INI-1/SMARCB1, SMARCA4, and NUT. Patients with these molecularly defined subsets of tumors may benefit from clinical trials that seek to exploit these molecular alterations. The EZH2 inhibitor, tazemetostat, has demonstrated some antitumor activity in INI-1-deficient tumors, and is currently under investigation.

Making the case for EGFR TKI sequencing in EGFR mutation-positive NSCLC: a GioTag study US patient analysis.

Aim: To assess time-to-treatment failure (TTF) in US patients with EGFR mutation-positive non-small-cell lung cancer (NSCLC) who received sequential afatinib-osimertinib treatment in the global, observational GioTag study. Patients & methods: Patients had EGFR T790M mutation-positive disease after first-line afatinib and subsequently received osimertinib. The primary outcome was TTF. Results: In 129 patients at US centers, median TTF was 28.4 months (90% CI: 27.0-34.1). Median overall survival was 47.6 months (90% CI: 35.5-51.5). Conclusion: Sequential afatinib-osimertinib in this US-treated population was associated with long median TTF and represents an effective, evidence-based treatment option for US patients with EGFR mutation-positive NSCLC not presenting with active brain metastases or de novo T790M. Clinical Trial Registration: NCT03370770 (ClinicalTrials.gov).

Sequential afatinib and osimertinib in patients with EGFR mutation-positive non-small-cell lung cancer: final analysis of the GioTag study.

Aim: Final overall survival (OS) and time on treatment analysis of patients with EGFR mutation-positive non-small-cell lung cancer (NSCLC) who received sequential afatinib and osimertinib. Patients & methods: Patients (n = 203) had T790M-positive disease following first-line afatinib and started osimertinib treatment ≥10 months before data entry. Primary outcome was time on treatment; OS analysis was exploratory. Results: Median time on treatment with afatinib and osimertinib was 27.7 months (90% CI: 26.7-29.9). Median OS was 37.6 months (90% CI: 35.5-41.3); median OS was 41.6 and 44.8 months in Del19-positive patients and Asian patients, respectively. Conclusion: In real-world clinical practice, sequential afatinib and osimertinib was associated with encouraging outcomes in patients with EGFR mutation-positive NSCLC, especially in Del19-positive patients and Asian patients. Clinical Trial Registration: NCT03370770 (ClinicalTrials.gov).

Sequential afatinib and osimertinib in patients with EGFR mutation-positive non-small-cell lung cancer: updated analysis of the observational GioTag study.

Aims: Overall survival (OS) and updated time to treatment failure (TTF) analysis of patients with EGFR mutation-positive (Del19, L858R) non-small-cell lung cancer who received sequential afatinib/osimertinib in the real-world GioTag study. Patients & methods: Patients had T790M-positive disease following first-line afatinib and received osimertinib treatment (n = 203). Primary outcome was TTF. The OS analysis was exploratory. Results: Median OS was 41.3 months (90% CI: 36.8-46.3) overall and 45.7 months (90% CI: 45.3-51.5) in patients with Del19-positive tumors (n = 149); 2-year survival was 80 and 82%, respectively. Updated median TTF with afatinib and osimertinib was 28.1 months (90% CI: 26.8-30.3). Conclusion: Sequential afatinib/osimertinib was associated with encouraging OS/TTF in patients with EGFR T790M-positive non-small-cell lung cancer, especially in patients with Del19-positive tumors. Trial registration number: NCT03370770.

Sequential treatment with afatinib and osimertinib in patients with EGFR mutation-positive non-small-cell lung cancer: an observational study.

AIM: To assess outcomes in patients with EGFR mutation-positive (Del19, L858R) non-small-cell lung cancer receiving sequential afatinib and osimertinib in a real-world clinical setting. Materials & methods: In this retrospective, observational, multicenter study, patients (n = 204) had T790M-positive disease following first-line afatinib and started osimertinib treatment ≥10 months prior to data entry. Primary outcome was time on treatment. RESULTS: Overall median time on treatment was 27.6 months (90% CI: 25.9-31.3), 30.3 months (90% CI: 27.6-44.5) in Del19-positive patients and 46.7 months (90% CI: 26.8-not reached) in Asians. The 2-year overall survival was 78.9%. CONCLUSION: In real-world clinical practice, sequential afatinib and osimertinib facilitates prolonged, chemotherapy-free treatment in patients with T790M acquired resistance, and is a potentially attractive strategy, especially for Del19-positive tumors. TRIAL REGISTRATION NUMBER: NCT03370770.

DNA Polymerase ɛ Deficiency Leading to an Ultramutator Phenotype: A Novel Clinically Relevant Entity.

Deficiencies in DNA repair due to mutations in the exonuclease domain of DNA polymerase ɛ have recently been described in a subset of cancers characterized by an ultramutated and microsatellite stable (MSS) phenotype. This alteration in DNA repair is distinct from the better-known mismatch repair deficiencies which lead to microsatellite instability (MSI) and an increased tumor mutation burden. Instead, mutations in POLE lead to impaired proofreading intrinsic to Pol ɛ during DNA replication resulting in a dramatically increased mutation rate. Somatic mutations of Pol ɛ have been found most frequently in endometrial and colorectal cancers (CRC) and can lead to a unique familial syndrome in the case of germline mutations. While other key genomic abnormalities, such as MSI, have known prognostic and treatment implications, in this case it is less clear. As molecular genotyping of tumors becomes routine in the care of cancer patients, less common, but potentially actionable findings such as these POLE mutations could be overlooked unless appropriate algorithms are in place. We present two cases of metastatic CRC with a POLE mutation, both of which are ultramutated and MSS. The basic biochemical mechanisms leading to a unique phenotype in POLE deficiency as well as challenges faced with interpreting the genomic profiling of tumors in this important subset of patients and the potential clinical implications will be discussed here. The Oncologist 2017;22:497-502 KEY POINTS: Clinicians should recognize that tumors with high tumor mutation burden and that are microsatellite stable may harbor a POLE mutation, which is associated with an ultramutated phenotype.Work-up for POLE deficiency should indeed become part of the routine molecular testing paradigm for patients with colorectal cancer.This subset of patients may benefit from clinical trials where the higher number of mutation-associated neoantigens and defect in DNA repair may be exploited therapeutically.

Sunitinib activates Axl signaling in renal cell cancer.

Mass spectrometry-based phosphoproteomics provides a unique unbiased approach to evaluate signaling network in cancer cells. The tyrosine kinase inhibitor sunitinib is registered as treatment for patients with renal cell cancer (RCC). We investigated the effect of sunitinib on tyrosine phosphorylation in RCC tumor cells to get more insight in its mechanism of action and thereby to find potential leads for combination treatment strategies. Sunitinib inhibitory concentrations of proliferation (IC50) of 786-O, 769-p and A498 RCC cells were determined by MTT-assays. Global tyrosine phosphorylation was measured by LC-MS/MS after immunoprecipitation with the antiphosphotyrosine antibody p-TYR-100. Phosphoproteomic profiling of 786-O cells yielded 1519 phosphopeptides, corresponding to 675 unique proteins including 57 different phosphorylated protein kinases. Compared to control, incubation with sunitinib at its IC50 of 2 µM resulted in downregulation of 86 phosphopeptides including CDK5, DYRK3, DYRK4, G6PD, PKM and LDH-A, while 94 phosphopeptides including Axl, FAK, EPHA2 and p38α were upregulated. Axl- (y702), FAK- (y576) and p38α (y182) upregulation was confirmed by Western Blot in 786-O and A498 cells. Subsequent proliferation assays revealed that inhibition of Axl with a small molecule inhibitor (R428) sensitized 786-O RCC cells and immortalized endothelial cells to sunitinib up to 3 fold. In conclusion, incubation with sunitinib of RCC cells causes significant upregulation of multiple phosphopeptides including Axl. Simultaneous inhibition of Axl improves the antitumor activity of sunitinib. We envision that evaluation of phosphoproteomic changes by TKI treatment enables identification of new targets for combination treatment strategies.

Update in Lung Cancer 2014.

In the past 2 years, lung cancer research and clinical care have advanced significantly. Advancements in the field have improved outcomes and promise to lead to further reductions in deaths from lung cancer, the leading cause of cancer death worldwide. These advances include identification of new molecular targets for personalized targeted therapy, validation of molecular signatures of lung cancer risk in smokers, progress in lung tumor immunotherapy, and implementation of population-based lung cancer screening with chest computed tomography in the United States. In this review, we highlight recent research in these areas and challenges for the future.

Randomized Phase II Trial of Erlotinib Beyond Progression in Advanced Erlotinib-Responsive Non-Small Cell Lung Cancer.

BACKGROUND: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapy is clearly beneficial in patients with advanced EGFR-mutated non-small cell lung cancer (NSCLC). However, acquired resistance develops uniformly and the benefit of continuation of EGFR TKI therapy beyond progression remains unclear. MATERIALS AND METHODS: This was a randomized phase II study of chemotherapy (arm A: pemetrexed or docetaxel) versus chemotherapy plus erlotinib (ERL) (arm B) in patients with progressive NSCLC following clinical benefit from erlotinib. In arm B, chemotherapy was given with erlotinib at an oral daily dose of 150 mg on days 2-19 of each cycle to minimize negative pharmacodynamic interactions. The primary endpoint was that continuation of erlotinib in this patient population could extend progression-free survival (PFS) by 50%. RESULTS: A total of 46 patients were randomized (arm A: 24; arm B: 22). Patient characteristics were well balanced except there were more female patients in arm A (p = .075). The median PFS of patients in arm A was 5.5 months and for those in arm B, 4.4 months (p = .699). The response rates were 13% and 16% in arms A and B, respectively (p = .79). EGFR status data were available for 39 of the 46 patients and no significant difference in PFS was seen for continuing ERL beyond progression in mutation-positive patients. Substantially more toxicity was seen in arm B than arm A. CONCLUSION: There was added toxicity but no benefit with the continuation of ERL beyond progression along with chemotherapy as compared with chemotherapy alone. IMPLICATIONS FOR PRACTICE: The benefits of continuing erlotinib upon progression alongside conventional chemotherapy are unclear. This randomized phase II study, initiated prior to the establishment of routine epidermal growth factor receptor (EGFR) mutation testing, addressed this clinically relevant issue through randomizing patients with prior clinical benefit from erlotinib (thereby enriching for EGFR-mutated tumors) upon progression in the second- or third-line setting to conventional chemotherapy (single-agent pemetrexed or docetaxel) with or without continued erlotinib. The results showed no benefit to continuing erlotinib beyond progression, while significantly more side effects were noted in the combination arm. Along with other recently presented study findings, these results argue against the routine practice of continuing erlotinib in this setting.

PIAS3 activates the intrinsic apoptotic pathway in non-small cell lung cancer cells independent of p53 status.

Protein inhibitor of activated signal transducer and activator of transcription 3 (STAT3) (PIAS3) is an endogenous inhibitor of STAT3 that negatively regulates STAT3 transcriptional activity and cell growth and demonstrates limited expression in the majority of human squamous cell carcinomas of the lung. In this study, we sought to determine whether PIAS3 inhibits cell growth in non-small cell lung cancer cell lines by inducing apoptosis. Our results demonstrate that overexpression of PIAS3 promotes mitochondrial depolarization, leading to cytochrome c release, caspase 9 and 3 activation and poly (ADP-ribose) polymerase cleavage. This intrinsic pathway activation was associated with decreased Bcl-xL expression and increased Noxa expression and was independent of p53 status. Furthermore, PIAS3 inhibition of STAT3 activity was also p53 independent. Microarray experiments were performed to discover STAT3-independent mediators of PIAS3-induced apoptosis by comparing the apoptotic gene expression signature induced by PIAS3 overexpression with that induced by STAT3 siRNA. The results showed that a subset of apoptotic genes was uniquely expressed only after PIAS3 expression. Thus, PIAS3 may represent a promising lung cancer therapeutic target because of its p53-independent efficacy and its potential to synergize with Bcl-2 targeted inhibitors.