TP53, STK11, and EGFR Mutations Predict Tumor Immune Profile and the Response to Anti-PD-1 in Lung Adenocarcinoma

Molecular markers and prediction of response to immunotherapy in non-small cell lung cancer, an update

Immunotherapy represents one of the most promising therapeutic approaches in lung cancer, however 50% of lung cancer patients will not respond to this treatment, while others will have transitory or durable responses. Because side effects may be life threatening and treatment costs remain very high, the identification of predictive markers is mandatory and actually extensively studied. Factors that determine response to immune checkpoint inhibitors (ICI) are numerous including tumor microenvironment, immune tumor infiltrates, expression of immune checkpoint proteins (PD-1/PD-L1), gene expression signatures and molecular tumor profiles. Based on high impact factor publications and recent literature this review focuses on the potential predictive value of tumor molecular alterations and tumor mutation burden as predictive markers of response or resistance to ICI. We also discuss the role of circulating tumor DNA (ctDNA) to monitor ICI responses and propose an algorithm that integrates molecular markers upcoming recommendations for first line treatment.

Efficacy of nivolumab in pre-treated non-small-cell lung cancer patients harbouring KRAS mutations

BACKGROUND

The present study investigated the efficacy and safety of nivolumab in pre-treated patients with advanced NSCLC harbouring KRAS mutations.

METHODS

Clinical data and KRAS mutational status were analysed in patients treated with nivolumab within the Italian Expanded Access Program. Objective response rate, progression-free survival and overall survival were evaluated. Patients were monitored for adverse events using the National Cancer Institute Common Terminology Criteria for Adverse Events.

RESULTS

Among 530 patients evaluated for KRAS mutations, 206 (39%) were positive while 324 (61%) were KRAS wild-type mutations. KRAS status did not influence nivolumab efficacy in terms of ORR (20% vs 17%, P = 0.39) and DCR (47% vs 41%, P = 0.23). The median PFS and OS were 4 vs 3 months (P = 0.5) and 11.2 vs 10 months (P = 0.8) in the KRAS-positive vs the KRAS-negative group. The 3-months PFS rate was significantly higher in the KRAS-positive group as compared to the KRAS-negative group (53% vs 42%, P = 0.01). The percentage of any grade and grade 3-4 AEs were 45% vs 33% (P = 0.003) and 11% vs 6% (P = 0.03) in KRAS-positive and KRAS-negative groups, respectively.

CONCLUSIONS

Nivolumab is an effective and safe treatment option for patients with previously treated, advanced non-squamous NSCLC regardless of KRAS mutations.

Advances in multiple omics of natural-killer/T cell lymphoma

Natural-killer/T cell lymphoma (NKTCL) represents the most common subtype of extranodal lymphoma with aggressive clinical behavior. Prevalent in Asians and South Americans, the pathogenesis of NKTCL remains to be fully elucidated. Using system biology techniques including genomics, transcriptomics, epigenomics, and metabolomics, novel biomarkers and therapeutic targets have been revealed in NKTCL. Whole-exome sequencing studies identify recurrent somatic gene mutations, involving RNA helicases, tumor suppressors, JAK-STAT pathway molecules, and epigenetic modifiers. Another genome-wide association study reports that single nucleotide polymorphisms mapping to the class II MHC region on chromosome 6 contribute to lymphomagenesis. Alterations of oncogenic signaling pathways janus kinase-signal transducer and activator of transcription (JAK-STAT), nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), WNT, and NOTCH, as well as epigenetic dysregulation of microRNA and long non-coding RNAs, are also frequently observed in NKTCL. As for metabolomic profiling, abnormal amino acids metabolism plays an important role on disease progression of NKTCL. Of note, through targeting multiple omics aberrations, clinical outcome of NKTCL patients has been significantly improved by asparaginase-based regimens, immune checkpoints inhibitors, and histone deacetylation inhibitors. Future investigations will be emphasized on molecular classification of NKTCL using integrated analysis of system biology, so as to optimize targeted therapeutic strategies of NKTCL in the era of precision medicine.

Immunogenomic Landscape Contributes to Hyperprogressive Disease after Anti-PD-1 Immunotherapy for Cancer

Although PD-1-blocking immunotherapies demonstrate significant therapeutic promise, a subset of the patients could develop hyperprogressive disease (HPD) with accelerated tumor growth after anti-PD1 immunotherapy. To elucidate the underlying mechanisms, we compared the mutational and transcriptional landscapes between the pre- and post-therapy tumors of two patients developing HPD after anti-PD-1 immunotherapy. In post-therapy HPD tumors, somatic mutations were found in known cancer genes, including tumor suppressor genes such as TSC2 and VHL, along with transcriptional upregulation of oncogenic pathways, including IGF-1, ERK/MAPK, PI3K/AKT, and TGF-β. We found that post-therapy HPD tumors were less immunogenic than pre-therapy tumors, concurrent with an increased presence of ILC3 cells, a subset of innate lymphoid cells. We also developed a gene expression signature predictive of HPD. In summary, we identified the genomics and immune features associated with HPD, which may help identify patients at risk of adverse clinical outcome after anti-PD-1 immunotherapy.

Immunosuppressive circuits in tumor microenvironment and their influence on cancer treatment efficacy

It has been for long conceived that hallmarks of cancer were intrinsic genetic features driving tumor development, proliferation, and progression, and that targeting such cell-autonomous pathways could be sufficient to achieve therapeutic cancer control. Clinical ex vivo data demonstrated that treatment efficacy often relied on the contribution of host immune responses, hence introducing the concept of tumor microenvironment (TME), namely the existence, along with tumor cells, of non-tumor components that could significantly influence tumor growth and survival. Among the complex network of TME-driving forces, immunity plays a key role and the balance between antitumor and protumor immune responses is a major driver in contrasting or promoting cancer spreading. TME is usually a very immunosuppressed milieu because of a vast array of local alterations contrasting antitumor adaptive immunity, where metabolic changes contribute to cancer dissemination by impairing T cell infiltration and favoring the accrual and activation of regulatory cells. Subcellular structures known as extracellular vesicles then help spreading immunosuppression at systemic levels by distributing genetic and protein tumor repertoire in distant tissues. A major improvement in the knowledge of TME is now pointing the attention back to tumor cells; indeed, recent findings are showing how oncogenic pathways and specific mutations in tumor cells can actually dictate the nature and the function of immune infiltrate. As our information on the reciprocal interactions regulating TME increases, finding a strategy to interfere with TME crosstalk becomes more complex and challenging. Nevertheless, TME interactions represent a promising field for the discovery of novel biomarkers and therapeutic targets for improving treatment efficacy in cancer.

[Biomarkers predictive of PD1/PD-L1 immunotherapy in non-small cell lung cancer]

Immune checkpoint inhibitors (ICI), targeting the PD1/PD-L1 axis has shown their efficacy in lung cancer but only in a restricted population of patients, thus it is mandatory to identify biomarkers predicting the clinical benefit. In this article we will describe and analyzed biomarkers already published, from protein, to RNA and at last DNA markers, discussing each markers feasibility and interest. In the future, combined analysis of several markers will probably be proposed, particularly with the increasing complexity of therapy schema with molecules association.

Lung-Enriched Mutations in the p53 Tumor Suppressor: A Paradigm for Tissue-Specific Gain of Oncogenic Function

Lung cancer, the leading cause of cancer-related mortality in the United States, occurs primarily due to prolonged exposure to an array of carcinogenic compounds in cigarette smoke. These carcinogens create bulky DNA adducts, inducing alterations including missense mutations in the tumor suppressor gene TP53 TP53 is the most commonly mutated gene in many human cancers, and a specific set of these variants are enriched in lung cancer (at amino acid residues V157, R158, and A159). This perspective postulates that lung-enriched mutations can be explained, in part, by biological selection for oncogenic gain-of-function (GOF) mutant p53 alleles at V157, R158, and A159. This hypothesis explaining tissue-specific TP53 mutations is further supported by mouse model studies of the canonical TP53 hotspots showing that tumor spectra and GOF activities are altered with mutation type. Therefore, although smoking-related lung cancer unequivocally arises due to the mutagenic environment induced by tobacco carcinogens, this perspective provides a rationale for the preferential selection of lung-enriched V157, R158, and A159 mutant p53.