BMI, irAE, and gene expression signatures associate with resistance to immune-checkpoint inhibition and outcomes in renal cell carcinoma.

BACKGROUND: Clinical variables may correlate with lack of response to treatment (primary resistance) or clinical benefit in patients with clear cell renal cell carcinoma (ccRCC) treated with anti-programmed death 1/ligand one antibodies. METHODS: In this multi-institutional collaboration, clinical characteristics of patients with primary resistance (defined as progression on initial computed tomography scan) were compared to patients with clinical benefit using Two sample t-test and Chi-square test (or Fisher's Exact test). The Kaplan-Meier method was used to estimate the distribution of progression-free survival (PFS) and overall survival (OS) in all patients and the subsets of patients with clinical benefit or primary resistance. Cox's regression model was used to evaluate the correlation between survival endpoints and variables of interest. To explore clinical factors in a larger, independent patient sample, The Cancer Genome Atlas (TCGA) was analyzed. RNAseq gene expression data as well as demographic and clinical information were downloaded for primary tumors of 517 patients included within TCGA-ccRCC. RESULTS: Of 90 patients, 38 (42.2%) had primary resistance and 52 (57.8%) had clinical benefit. Compared with the cohort of patients with initial benefit, primary resistance was more likely to occur in patients with worse ECOG performance status (p = 0.03), earlier stage at diagnosis (p = 0.04), had no prior nephrectomy (p = 0.04) and no immune-related adverse events (irAE) (p = 0.02). In patients with primary resistance, improved OS was significantly correlated with lower International Metastatic RCC Database Consortium risk score (p = 0.02) and lower neutrophil:lymphocyte ratio (p = 0.04). In patients with clinical benefit, improved PFS was significantly associated with increased BMI (p = 0.007) and irAE occurrence (p = 0.02) while improved OS was significantly correlated with overweight BMI (BMI 25-30; p = 0.03) and no brain metastasis (p = 0.005). The cohort TCGA-ccRCC was examined for the correlations between gene expression patterns, clinical factors, and survival outcomes observing associations of T-cell inflammation and angiogenesis signatures with histologic grade, pathologic stage and OS. CONCLUSIONS: Clinical characteristics including performance status, BMI and occurrence of an irAE associate with outcomes in patients with ccRCC treated with immunotherapy. The inverse association of angiogenesis gene signature with ccRCC histologic grade highlight opportunities for adjuvant combination VEGFR2 tyrosine kinase inhibitor and immune-checkpoint inhibition.

Photodynamic Therapy Effectively Treats Actinic Keratoses Without Pre-Illumination Incubation Time.

BACKGROUND: Actinic keratoses (AKs) are dysplastic lesions of the epidermis that have the potential to progress to non-melanoma skin cancers (NMSC). Traditional photodynamic therapy (PDT) requires a pre-illumination incubation time, which adds to overall in-office time and has been linked to pain. Our group has found a novel protocol to effectively treat AKs with PDT that eliminates the pre-illumination incubation period and uses 2 back-to-back cycles of 16 minute 40 seconds.

METHODS: The patient was prepped with soapy water and isopropyl alcohol, and thick AKs were descaled with a curette. Next, 5-aminolevulinic acid (ALA) was applied to the treatment areas and the patient was immediately placed under the blue light for 33 minutes and 20 seconds (two cycles of 16m/40s).

RESULTS: During therapy, the patient reported no pain. At one week, treated areas revealed a good reaction. The procedure was repeated at one month to treat residual AKs. At a 4-month follow-up, the patient's face and scalp showed near clearance of any AKs.

CONCLUSION: During PDT, the photosensitizer aminolevulinic acid (ALA), or in Europe methyl aminolevulinate (MAL), is utilized as a synthetic precursor that preferentially accumulates in dysplastic cells. The precursor then converts to PpIX via the heme pathway and causes apoptosis of the cells when excited, most commonly by either blue-violet (400-430 nm) or red (630-635 nm) light. Shorter incubation times are associated with reduced pain because less PpIX will have accumulated in the treated tissue by the start of the exposure to the light. The doubling of the light exposure time allows comparable levels of the photosensitizing molecule to accumulate and be activated so as to produce an equivalent reaction. The associated reduction in pain along with a more convenient treatment schedule makes this PDT protocol more tolerable and convenient to some patients.

J Drugs Dermatol. 2017;16(3):275-278.

Suppression of tumor cell lactate-generating signaling pathways eradicates murine PTEN/p53-deficient aggressive-variant prostate cancer via macrophage phagocytosis.

Purpose: PTEN loss-of-function/PI3K pathway hyperactivation occurs in ∼50% of metastatic, castrate-resistant prostate cancer patients, resulting in poor therapeutic outcomes and resistance to immune checkpoint inhibitors across multiple malignancies. Our prior studies in prostate-specific PTEN/p53-deleted genetically engineered mice (Pb-Cre;PTEN fl/fl Trp53 fl/fl GEM) with aggressive-variant prostate cancer (AVPC) demonstrated feedback Wnt/ß-catenin signaling activation in 40% mice resistant to androgen deprivation therapy (ADT)/PI3K inhibitor (PI3Ki)/PD-1 antibody (aPD-1) combination, resulting in restoration of lactate cross-talk between tumor-cells and tumor-associated macrophages (TAM), histone lactylation (H3K18lac) and phagocytic suppression within TAM. Here, we targeted immunometabolic mechanism(s) of resistance to ADT/PI3Ki/aPD-1 combination, with the goal of durable tumor control in PTEN/p53-deficient PC. Experimental design: Pb-Cre;PTEN fl/fl Trp53 fl/fl GEM were treated with either ADT (degarelix), PI3Ki (copanlisib), aPD-1, MEK inhibitor (trametinib) or Porcupine inhibitor (LGK 974) as single agents or their combinations. MRI was used to monitor tumor kinetics and immune/proteomic profiling/ ex vivo co-culture mechanistic studies were performed on prostate tumors or established GEM-derived cell lines. Results: We tested whether Wnt/ß-catenin pathway inhibition with LGK 974 addition to degarelix/copanlisib/aPD-1 therapy enhances tumor control in GEM, and observed de novo resistance due to feedback activation of MEK signaling. Based on our observation that degarelix/aPD-1 treatment resulted in partial inhibition of MEK signaling, we substituted trametinib for degarelix/aPD-1 treatment, and observed a durable tumor growth control of PI3Ki/MEKi/PORCNi in 100% mice via H3K18lac suppression and complete TAM activation within TME. Conclusions: Abrogation of lactate-mediated cross-talk between cancer cells and TAM results in durable ADT-independent tumor control in PTEN/p53-deficient AVPC, and warrants further investigation in clinical trials. STATEMENT OF TRANSLATIONAL RELEVANCE: PTEN loss-of-function occurs in ∼50% of mCRPC patients, and associated with poor prognosis, and immune checkpoint inhibitor resistance across multiple malignancies. Our prior studies have demonstrated that ADT/PI3Ki/PD-1 triplet combination therapy controls PTEN/p53-deficient PC in 60% of mice via enhancement of TAM phagocytosis. Here, we discovered that resistance to ADT/PI3K/PD-1 therapy occurred via restoration of lactate production via feedback Wnt/MEK signaling following treatment with PI3Ki, resulting in inhibition of TAM phagocytosis. Critically, co-targeting of PI3K/MEK/Wnt signaling pathways using an intermittent dosing schedule of corresponding targeted agents resulted in complete tumor control and significantly prolonged survival without significant long-term toxicity. Collectively, our findings provide "proof-of-concept" that targeting lactate as a macrophage phagocytic checkpoint controls growth of murine PTEN/p53-deficient PC and warrant further investigation in AVPC clinical trials.

Suppression of Tumor Cell Lactate-generating Signaling Pathways Eradicates Murine PTEN/p53-deficient Aggressive-variant Prostate Cancer via Macrophage Phagocytosis.

PURPOSE: Phosphatase and tensin homolog (PTEN) loss-of-function/PI3K pathway hyperactivation is associated with poor therapeutic outcomes and immune checkpoint inhibitor resistance across multiple malignancies. Our prior studies in Pb-Cre;PTENfl/flTrp53fl/fl genetically engineered mice (GEM) with aggressive-variant prostate cancer (AVPC) demonstrated tumor growth control in 60% mice following androgen deprivation therapy/PI3K inhibitor (PI3Ki)/programmed cell death protein 1 (PD-1) antibody combination, via abrogating lactate cross-talk between cancer cells and tumor-associated macrophages (TAM), and suppression of histone lactylation (H3K18lac)/phagocytic activation within TAM. Here, we targeted immunometabolic mechanism(s) of PI3Ki resistance, with the goal of durable tumor control in AVPC. EXPERIMENTAL DESIGN: Pb-Cre;PTENfl/flTrp53fl/fl GEM were treated with PI3Ki (copanlisib), MEK inhibitor (trametinib) or Porcupine inhibitor (LGK'974) singly or their combinations. MRI was used to monitor tumor kinetics and immune/proteomic profiling/ex vivo coculture mechanistic studies were performed on GEM tumors or corresponding tumor-derived cell lines. RESULTS: Given our proteomic profiling showing persistent MEK signaling within tumors of PI3Ki-resistant GEM, we tested whether addition of trametinib to copanlisib enhances tumor control in GEM, and we observed 80% overall response rate via additive suppression of lactate within TME and H3K18lac within TAM, relative to copanlisib (37.5%) monotherapy. The 20% resistant mice demonstrated feedback Wnt/ß-catenin activation, resulting in restoration of lactate secretion by tumor cells and H3K18lac within TAM. Cotargeting Wnt/ß-catenin signaling with LGK'974 in combination with PI3Ki/MEKi, demonstrated durable tumor control in 100% mice via H3K18lac suppression and complete TAM activation. CONCLUSIONS: Abrogation of lactate-mediated cross-talk between cancer cells and TAM results in durable ADT-independent tumor control in PTEN/p53-deficient AVPC, and warrants further investigation in clinical trials.

Androgen blockade primes NLRP3 in macrophages to induce tumor phagocytosis.

Immune-based therapies induce durable remissions in subsets of patients across multiple malignancies. However, there is limited efficacy of immunotherapy in metastatic castrate-resistant prostate cancer (mCRPC), manifested by an enrichment of immunosuppressive (M2) tumor- associated macrophages (TAM) in the tumor immune microenvironment (TME). Therefore, therapeutic strategies to overcome TAM-mediated immunosuppression are critically needed in mCRPC. Here we discovered that NLR family pyrin domain containing 3 (NLRP3), an innate immune sensing protein, is highly expressed in TAM from metastatic PC patients treated with standard-of-care androgen deprivation therapy (ADT). Importantly, ex vivo studies revealed that androgen receptor (AR) blockade in TAM upregulates NLRP3 expression, but not inflammasome activity, and concurrent AR blockade/NLRP3 agonist (NLRP3a) treatment promotes cancer cell phagocytosis by immunosuppressive M2 TAM. In contrast, NLRP3a monotherapy was sufficient to enhance phagocytosis of cancer cells in anti-tumor (M1) TAM, which exhibit high de novo NLRP3 expression. Critically, combinatorial treatment with ADT/NLRP3a in a murine model of advanced PC resulted in significant tumor control, with tumor clearance in 55% of mice via TAM phagocytosis. Collectively, our results demonstrate NLRP3 as an AR-regulated "macrophage phagocytic checkpoint", inducibly expressed in TAM by ADT and activated by NLRP3a treatment, the combination resulting in TAM-mediated phagocytosis and tumor control.

Reversal of Lactate and PD-1-mediated Macrophage Immunosuppression Controls Growth of PTEN/p53-deficient Prostate Cancer.

PURPOSE: Phosphatase and tensin homolog (PTEN) loss of function occurs in approximately 50% of patients with metastatic castrate-resistant prostate cancer (mCRPC), and is associated with poor prognosis and responsiveness to standard-of-care therapies and immune checkpoint inhibitors. While PTEN loss of function hyperactivates PI3K signaling, combinatorial PI3K/AKT pathway and androgen deprivation therapy (ADT) has demonstrated limited anticancer efficacy in clinical trials. Here, we aimed to elucidate mechanism(s) of resistance to ADT/PI3K-AKT axis blockade, and to develop rational combinatorial strategies to effectively treat this molecular subset of mCRPC. EXPERIMENTAL DESIGN: Prostate-specific PTEN/p53-deficient genetically engineered mice (GEM) with established 150-200 mm3 tumors, as assessed by ultrasound, were treated with either ADT (degarelix), PI3K inhibitor (copanlisib), or anti-PD-1 antibody (aPD-1), as single agents or their combinations, and tumors were monitored by MRI and harvested for immune, transcriptomic, and proteomic profiling, or ex vivo co-culture studies. Single-cell RNA sequencing on human mCRPC samples was performed using 10X Genomics platform. RESULTS: Coclinical trials in PTEN/p53-deficient GEM revealed that recruitment of PD-1-expressing tumor-associated macrophages (TAM) thwarts ADT/PI3Ki combination-induced tumor control. The addition of aPD-1 to ADT/PI3Ki combination led to TAM-dependent approximately 3-fold increase in anticancer responses. Mechanistically, decreased lactate production from PI3Ki-treated tumor cells suppressed histone lactylation within TAM, resulting in their anticancer phagocytic activation, which was augmented by ADT/aPD-1 treatment and abrogated by feedback activation of Wnt/ß-catenin pathway. Single-cell RNA-sequencing analysis in mCRPC patient biopsy samples revealed a direct correlation between high glycolytic activity and TAM phagocytosis suppression. CONCLUSIONS: Immunometabolic strategies that reverse lactate and PD-1-mediated TAM immunosuppression, in combination with ADT, warrant further investigation in patients with PTEN-deficient mCRPC.

Guidelines for Management of Treatment-Emergent Adverse Events During Rucaparib Treatment of Patients with Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: The US Food and Drug Administration has recently granted accelerated approval of the poly(ADP-ribose) polymerase (PARP) inhibitor rucaparib as treatment for men with metastatic castration-resistant prostate cancer (mCRPC) associated with a deleterious germline or somatic BRCA1 or BRCA2 (BRCA) alteration. As the safety profile of this new addition to the mCRPC treatment landscape may be unfamiliar to clinicians and patients, we summarize the data from the literature and provide practical guidelines for the management of treatment-emergent adverse events (TEAEs) that may occur during rucaparib treatment. MATERIALS AND METHODS: Safety data were identified from PubMed and congress publications of trials involving men with mCRPC treated with oral rucaparib monotherapy (600 mg twice daily). Management guidelines for TEAEs were developed based on trial protocols, prescribing information, oncology association guidance, and the authors' clinical experience. RESULTS: In clinical trials of men with mCRPC who received rucaparib (n = 193), TEAEs observed were consistent with that of other PARP inhibitors. The most frequent any-grade TEAEs included gastrointestinal events, asthenia/fatigue, anemia, increased alanine/aspartate aminotransferase, rash, and thrombocytopenia; the most frequent grade ≥3 TEAE was anemia. The majority of TEAEs were self-limiting and did not require treatment modification or interruption. Here, we provide recommendations on management of the most common TEAEs reported with rucaparib as well as other TEAEs of interest. CONCLUSION: Rucaparib's recent approval for treatment of BRCA-mutant mCRPC is practice changing. Proper management of TEAEs will allow maximum treatment benefit for patients receiving rucaparib.

Immune Checkpoint Inhibitors for Genitourinary Cancers: Treatment Indications, Investigational Approaches and Biomarkers.

Cancers of the genitourinary (GU) tract are common malignancies in both men and women and are a major source of morbidity and mortality. Immune checkpoint inhibitors (ICI) targeting CTLA-4, PD-1 or PD-L1 have provided clinical benefit, particularly in renal cell and urothelial carcinoma, and have been incorporated into standard of care treatment in both localized and metastatic settings. However, a large fraction of patients do not derive benefit. Identification of patient and tumor-derived factors which associate with response have led to insights into mechanisms of response and resistance to ICI. Herein, we review current approvals and clinical development of ICI in GU malignancies and discuss exploratory biomarkers which aid in personalized treatment selection.

Targeting Innate Immunity in Cancer Therapy.

The majority of current cancer immunotherapy strategies target and potentiate antitumor adaptive immune responses. Unfortunately, the efficacy of these treatments has been limited to a fraction of patients within a subset of tumor types, with an aggregate response rate of approximately 20% to date across all malignancies. The success of therapeutic inhibition of programmed death protein 1 (PD-1), protein death ligand 1 (PD-L1) and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) with immune checkpoint inhibitors (ICI) has been limited to "hot" tumors characterized by preexisting T cell infiltration, whereas "cold" tumors, which lack T cell infiltration, have not achieved durable benefit. There are several mechanisms by which "cold" tumors fail to generate spontaneous immune infiltration, which converge upon the generation of an immunosuppressive tumor microenvironment (TME). The role of the innate immune system in tumor immunosurveillance and generation of antitumor immune responses has been long recognized. In recent years, novel strategies to target innate immunity in cancer therapy have emerged, including therapeutic stimulation of pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs); the DNA sensing cGAS/STING pathway; nucleotide-binding oligomerization domain-like receptors (NLRs), such as NLRP3; and the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs). In addition, therapeutic modulation of key innate immune cell types, such as macrophages and natural killer cells, has been investigated. Herein, we review therapeutic approaches to activate innate immunity within the TME to enhance antitumor immune responses, with the goal of disease eradication in "cold" tumors. In addition, we discuss rational immune-oncology combination strategies that activate both innate and adaptive immunity, with the potential to enhance the efficacy of current immunotherapeutic approaches.

Transcriptional analysis of metastatic uveal melanoma survival nominates NRP1 as a therapeutic target.

Uveal melanoma is a rare form of melanoma with particularly poor outcomes in the metastatic setting. In contrast with cutaneous melanoma, uveal melanoma lacks BRAF mutations and demonstrates very low response rates to immune-checkpoint blockade. Our objectives were to study the transcriptomics of metastatic uveal melanoma with the intent of assessing gene pathways and potential molecular characteristics that might be nominated for further exploration as therapeutic targets. We initially analyzed transcriptional data from The Cancer Genome Atlas suggesting PI3K/mTOR and glycolysis as well as IL6 associating with poor survival. From tumor samples collected in a prospective phase II trial (A091201), we performed a transcriptional analysis of human metastatic uveal melanoma observing a novel role for epithelial-mesenchymal transition associating with survival. Specifically, we nominate and describe initial functional validation of neuropillin-1 from uveal melanoma cells as associated with poor survival and as a mediator of proliferation and migration for uveal melanoma in vitro. These results immediately nominate potential next steps in clinical research for patients with metastatic uveal melanoma.

Pembrolizumab Plus Ipilimumab Following Anti-PD-1/L1 Failure in Melanoma.

PURPOSE: Combination of antiprogrammed cell death protein-1 (PD-1) plus anti-cytotoxic T-cell lymphocyte-4 (anti-CTLA-4) immunotherapy shows greater response rates (RRs) than anti-PD-1 antibody alone in melanoma, but RR after initial anti-PD-1 and programmed death ligand-1 (PD-L1) antibody progression awaits robust investigation. Anti-CTLA-4 antibody alone after anti-PD-1/L1 antibody progression has a historical RR of 13%. We report the results of the first prospective clinical trial evaluating ipilimumab 1 mg/kg plus pembrolizumab following progression on anti-PD-1 immunotherapy. METHODS: Patients with advanced melanoma who had progressed on anti-PD-1/L1 antibody as immediate prior therapy (including non-anti-CTLA-4 antibody combinations) were eligible. Patients received pembrolizumab 200 mg plus ipilimumab 1 mg/kg once every 3 weeks for four doses, followed by pembrolizumab monotherapy. The primary end point was RR by irRECIST. After 35 patients, the trial met the primary end point and was expanded to enroll a total of 70 patients to better estimate the RR. RESULTS: Prior treatments included 60 on anti-PD-1 antibody alone and 10 on anti-PD-1/L1 antibody-based combinations. Thirteen patients had progressed in the adjuvant setting. The median length of prior treatment with anti-PD-1/L1 antibody was 4.8 months. Response assessments included five complete and 15 partial responses, making the irRECIST RR 29% among the entire trial population. The median progression-free survival was 5.0 months, and the median overall survival was 24.7 months. The median duration of response was 16.6 months. There was no difference in median time on prior anti-PD1/L1 or time to PD1 + CTLA4 initiation between responders and nonresponders. Grade 3-4 drug-related adverse events occurred in 27% of patients. Responses occurred in PD-L1-negative, non-T-cell-inflamed, and intermediate tumor phenotypes. CONCLUSION: To our knowledge, this is the first prospective study in melanoma of pembrolizumab plus low-dose ipilimumab after anti-PD-1/L1 immunotherapy failure, demonstrating significant antitumor activity and tolerability.

Randomized Phase II Trial and Tumor Mutational Spectrum Analysis from Cabozantinib versus Chemotherapy in Metastatic Uveal Melanoma (Alliance A091201).

PURPOSE: The surface receptor MET is highly expressed on primary uveal melanoma; MET inhibitors demonstrated early clinical signals of efficacy in slowing uveal melanoma growth. The primary objective of our study was to compare the progression-free survival rate at 4 months (PFS4) of patients with uveal melanoma treated with cabozantinib or chemotherapy. PATIENTS AND METHODS: Patients with metastatic uveal melanoma and RECIST measurable disease were randomized 2:1 to receive either cabozantinib (arm 1) versus temozolomide or dacarbazine (arm 2) with restaging imaging every two cycles. Cross-over from arm 2 to cabozantinib after progression was allowed (arm 2X). Available tumor specimens were analyzed by whole-exome sequencing (WES) and results were correlated with outcome. RESULTS: Forty-six eligible patients were accrued with 31, 15, and 9 in arms 1, 2, and 2X, respectively. Median lines of prior therapy, including hepatic embolization, were two. Rates of PFS4 in arm 1 and arm 2 were 32.3% and 26.7% (P = 0.35), respectively, with median PFS time of 60 and 59 days (P = 0.964; HR = 0.99). Median overall survival (OS) was 6.4 months and 7.3 months (P = 0.580; HR = 1.21), respectively. Grade 3-4 Common Terminology Criteria for Adverse Events were present in 61.3%, 46.7%, and 37.5% in arms 1, 2, and 2X, respectively. WES demonstrated a mean tumor mutational burden of 1.53 mutations/Mb and did not separate OS ≤ or >1 year (P = 0.14). Known mutations were identified by WES and novel mutations were nominated. CONCLUSIONS: MET/VEGFR blockade with cabozantinib demonstrated no improvement in PFS but an increase in toxicity relative to temozolomide/dacarbazine in metastatic uveal melanoma.

Reimagining IDO Pathway Inhibition in Cancer Immunotherapy via Downstream Focus on the Tryptophan-Kynurenine-Aryl Hydrocarbon Axis.

Significant progress has been made in cancer immunotherapy with checkpoint inhibitors targeting programmed cell death protein 1 (PD-1)-programmed death-ligand 1 signaling pathways. Tumors from patients showing sustained treatment response predominately demonstrate a T cell-inflamed tumor microenvironment prior to, or early on, treatment. Not all tumors with this phenotype respond, however, and one mediator of immunosuppression in T cell-inflamed tumors is the tryptophan-kynurenine-aryl hydrocarbon receptor (Trp-Kyn-AhR) pathway. Multiple mechanisms of immunosuppression may be mediated by this pathway including depletion of tryptophan, direct immunosuppression of Kyn, and activity of Kyn-bound AhR. Indoleamine 2,3-dioxygenase 1 (IDO1), a principle enzyme in Trp catabolism, is the target of small-molecule inhibitors in clinical development in combination with PD-1 checkpoint inhibitors. Despite promising results in early-phase clinical trials in a range of tumor types, a phase III study of the IDO1-selective inhibitor epacadostat in combination with pembrolizumab showed no difference between the epacadostat-treated group versus placebo in patients with metastatic melanoma. This has led to a diminution of interest in IDO1 inhibitors; however, other approaches to inhibit this pathway continue to be considered. Novel Trp-Kyn-AhR pathway inhibitors, such as Kyn-degrading enzymes, direct AhR antagonists, and tryptophan mimetics are advancing in early-stage or preclinical development. Despite uncertainty surrounding IDO1 inhibition, ample preclinical evidence supports continued development of Trp-Kyn-AhR pathway inhibitors to augment immune-checkpoint and other cancer therapies.

Requirements for Meaningful Progress in the Therapy of Neuroendocrine Cancers.

This Viewpoint discusses the role of data interpretation and clinical trial design in improving therapy of neuroendocrine cancers.

Review of diagnostic, prognostic, and predictive biomarkers in melanoma.

Melanoma is an aggressive cutaneous malignancy with rapidly rising incidence. Diagnosis of controversial melanocytic lesions, correct prognostication of patients, selection of appropriate adjuvant and systemic therapies, and prediction of response to a given therapy remain very real challenges. Despite these challenges, multiple high throughput, nucleic-acid based biomarkers have been developed that can be assayed from histologic tissue specimens. FISH, CGH, Decision-Dx, and other multi-marker assays have been combined to improve overall predictability. This review discusses some of the most promising nucleic acid based assays that can be obtained from tissue specimens to assist with diagnosis, prognostication, and prediction of treatment response.

Clinical and molecular features of innate and acquired resistance to anti-PD-1/PD-L1 therapy in lung cancer.

HYPOTHESIS: The majority of non-small cell lung cancer (NSCLC) patients treated with anti-PD-1/PD-L1 therapy develop either innate or acquired resistance. Across tumor types, the "T cell-inflamed" tumor microenvironment correlates with clinical response to immunotherapy. We hypothesize that clinical characteristics may be predictive of resistance and that "T cell-inflamed" NSCLC tumors can be identified by gene expression profiling. RESULTS: Of 93 patients, 36 (38.7%) had innate resistance and 57 (61.3%) had initial benefit to immunotherapy. Innate resistance was associated with non-smokers (p = 0.013), more involved disease sites (p = 0.011), more prior therapy (p = 0.001), and a lower albumin level (p = 0.014). Among patients with initial benefit, factors associated with subsequent progression-free survival included higher Karnofsky Performance Status (KPS) (p = 0.004) and lower depth of response to anti-PD-1 therapy (p = 0.003). A "T cell-inflamed" microenvironment was identified in 42% of TCGA adenocarcinoma samples versus 21.0% of squamous cell. DISCUSSION: Specific clinical characteristics appear to be predictive of either innate or acquired resistance to anti-PD-1/PD-L1 therapy. A "T cell-inflamed" tumor was more common in adenocarcinoma than squamous histology. METHODS: A retrospective review of NSCLC patients treated with anti-PD-1/PD-L1 monotherapy. Patients with innate resistance to anti-PD-1/PD-L1 therapy (defined as progression at first CT evaluation) were compared to patients with initial clinical benefit. Among those with initial clinical benefit, we identified prognostic factors for time to progression (acquired resistance) or death. To further corroborate our findings on limited numbers, immune gene expression profiling of all NSCLC samples from the TCGA database was also pursued.