Loss of HRD functional phenotype impedes immunotherapy and can be reversed by HDAC inhibitor in ovarian cancer.

In recent years, homologous recombination deficiency (HRD) has not achieved the expected substantial promotion of immunotherapeutic efficacy in ovarian cancer. This study aims to explore the role of HRD functional phenotype as a powerful biomarker in identifying HRD patients who may benefit from immunotherapy. HRD functional phenotype, namely HRD-EXCUTE, was defined as the average level of the 15 hub genes upregulated in HRD ovarian cancer. A decision tree was plotted to evaluate the critical role of HRD-EXCUTE in HRD patients. Agents inducing HRD-EXCUTE were identified by CMAP web (Connectivity Map). The mechanisms and immunotherapeutic effect of PARPi and HDACi in promoting HRD-EXCUTE was examined in vitro and in vivo. The decision tree plotted on the basis of HRD and HRD-EXCUTE indicated the HRD patients without the HRD functional phenotype were largely unresponsive to immunotherapy, which was validated by the immunotherapeutic cohorts. Furthermore, loss of HRD-EXCUTE in the HRD patients attenuated immunogenicity and inhibited immune cells in tumor microenvironment. Moreover, Niraparib combined with Entinostat induced HRD-EXCUTE by activating the cGAS-STING pathway and increasing the histone acetylation. The combination therapy could enhance the cytotoxicity of immune cells, and promote pro-immune cells infiltrating into ascites, resulting in inhibited ovarian cancer growth. The HRD functional phenotype HRD-EXCUTE was set up as a potent biomarker to identify whether HRD patients can benefit from immunotherapy. Loss of HRD-EXCUTE in HRD patients were largely insensitive to immunotherapy. The combination of PARPi with HDACi could improve the efficacy of the PARPi-based immunotherapy in ovarian cancer by augmenting the HRD functional phenotype.

Efficacy and safety of immune checkpoint inhibitors with or without radiotherapy in metastatic non-small cell lung cancer: A systematic review and meta-analysis.

Background and purpose: Although immune checkpoint inhibitors (ICIs) have become the first-line treatment for metastatic non-small cell lung cancer (mNSCLC), their efficacy is limited. Meanwhile, recent reports suggest that radiotherapy (RT) can activate the systemic antitumor immune response by increasing the release of antigens from tumor tissues. Therefore, in patients with mNSCLC treated with ICIs, investigations were performed to determine whether the addition of RT improved the outcomes. Furthermore, the adverse events rate was evaluated. Methods and materials: Pubmed, Embase, and Cochrane Library were searched using the keywords "radiotherapy," "immune checkpoint inhibitors," and "non-small cell lung cancer" from the date of inception to 2 May 2022. Randomized controlled trials (RCTs) and nonRCTs (NRCTs) comparing the efficacy and safety of RT combined with ICIs versus ICIs alone in metastatic NSCLC were assessed. The primary outcomes were progression-free survival (PFS) and overall survival (OS), and the secondary outcomes were abscopal response rate (ARR), abscopal control rate (ACR), adverse events rate, and pneumonia rate. The analyses were conducted using the Mantel-Haenszel fixed-effects or random-effects model. The I2 statistic was used to determine heterogeneity, whereas funnel plots and Egger's test were used to assess publication bias. Results: In 15 clinical studies, 713 patients received RT combined with ICIs and 1,275 patients received only ICIs. With regard to PFS and OS, the hazard ratios of RT combined with ICIs were 0.79 (0.70, 0.89) and 0.72 (0.63, 0.82), respectively. In terms of ARR and ACR, the odds ratios (ORs) of RT combined with ICIs were 1.94 (1.19, 3.17) and 1.79 (1.08, 2.97), respectively. Subgroup analyses based on study type (RCT/NRCT), RT target (intracranial/extracranial), number of RT sites (single site), previous ICI resistance (yes/no), and sequencing of RT and ICIs (concurrent/post-RT ICIs) revealed that the addition of RT significantly prolonged PFS and OS. However, subgroup analyses based on radiation dose/fractionation indicated that the addition of hypofractionated RT significantly prolonged OS but not PFS. When grouped according to the level of PD-L1 expression, the addition of RT prolonged PFS only in patients who were PD-L1-negative. Furthermore, subgroup analyses of ARR and ACR signified that the combination therapy resulted in better local control of lesions outside the irradiation field in the hypofractionated RT, extracranial RT, and ICI-naïve subgroups. In terms of adverse events, the addition of RT did not significantly increase the adverse events rate but was associated with a higher pneumonia rate [OR values were 1.24 (0.92, 1.67) and 1.76 (1.12, 2.77), respectively]. Conclusion: Meta-analysis of existing data suggests that the addition of RT can significantly prolong PFS and OS in patients with metastatic NSCLC receiving ICIs. In addition to lesions in the irradiation field, RT can improve the local control rate of lesions outside the irradiation field via immune activation. Combination therapy does not increase the overall risk of adverse reactions, except for pneumonia.

Clinical features and response to systemic therapy in NRAS-mutant Chinese melanoma patients.

PURPOSE: The prognosis of patients with NRAS-mutant melanoma is rather poor. Immunotherapy and targeted therapy have revolutionized anti-tumor therapy, especially for melanoma. In this study, we retrospectively summarized the real-world experience of systematic treatment for NRAS-mutant melanoma patients in this new era. PATIENTS AND METHODS: The respective cohort included NRAS-mutant melanoma patients with metastatic or unresectable disease of Sun Yat-sen University Cancer Center (SYSUCC) from January 2018 to July 2022. The data about the clinical features and impact for systemic therapy of NRAS-mutant patients were collected and analyzed. RESULTS: At data cutoff, 44 patients (19, 11, and 14 for acral, cutaneous, and mucosal ones, respectively) with NRAS-mutant were assessed. In addition, the median time of follow-up was 22.0 months. The immunotherapy-based combined treatment not only significantly improved the progression-free survival (PFS) (P = 0.006, HR 0.322), but was also accompanied by a higher objective response rate (ORR) (18.2%), disease control rate (DCR) (72.7%) than those of cytotoxic therapy or immunotherapy alone for advanced patients as first-line treatment. Nab-paclitaxel combined with anti-PD-1 inhibitor tended to produce better clinical benefit for the first-line treatment, especially for patients with acral melanoma. In addition, the tyrosine kinase inhibitor (TKI) combined with anti-PD-1 inhibitor also seemed to provide longer duration of response (DOR) for some patients. But combined therapy did not prolong the overall survival (OS) of NRAS-mutant patients. The combined therapy was well tolerated. Most adverse events were moderate and controllable. CONCLUSION: In conclusion, PD-1 inhibitor-based combined therapy increased clinical benefit for advanced patients with NRAS-mutant melanoma.

HHLA2 predicts improved prognosis of anti-PD-1/PD-L1 immunotherapy in patients with melanoma.

Background: As a recognized highly immunogenic tumor, immune checkpoint blockades (ICB) have been widely used as a systemic treatment option for melanoma. However, only about half of treated patients could benefit from it in Caucasians, and only about 15% in Chinese melanoma patients. Robust predictive biomarkers are needed. HHLA2, a new-found member of B7 family, is generally expressed in kinds of tumors, such as melanoma. This study focuses on illustrating the prognostic value of HHLA2 in melanoma immunotherapy and its association with tumor-infiltrating lymphocytes. Methods: HHLA2 expression in pan-cancer and the association with prognosis and immune microenvironment were identified by analyzing gene expression profiles from TCGA database with selected bioinformatics tools and methods. Tumor tissues from 81 cases with advanced and unresectable melanoma were collected for detecting HHLA2 and CD8 levels by immunohistochemistry. Results: HHLA2 was found to be ubiquitously expressed in pan-cancer with high level and correlate with the prognosis of patients. Further comprehensive analysis from TCGA database demonstrated that the highly expressed HHLA2 was remarkably correlated with better prognosis, high infiltration status of various immune-active cells and immune activated pathways in skin cutaneous melanoma (SKCM). Moreover, immunohistochemistry (IHC) analyses of FFPE tissue from melanoma patients revealed that HHLA2 high expression was strongly related to improved response to ICB and indicated a longer progression-free survival (PFS) and overall survival (OS). Besides, HHLA2 expression was found to have a positive association with the density of CD8+ TILs. Conclusion: Our findings revealed that high expression of HHLA2 has important values in predicting the response to ICB and indicating improved PFS and OS in patients with advanced and unresectable melanoma, suggesting that HHLA2 may serve as a costimulatory ligand in melanoma, which renders it as an ideal biomarker for immunotherapy.

Next-generation sequencing in advanced Chinese melanoma reveals therapeutic targets and prognostic biomarkers for immunotherapy.

Limited studies have interrogated the genomic landscape of Chinese melanoma in which acral and mucosal melanoma are the mainstay. In this study, we carried out a retrospective analysis on 81 Chinese melanoma patients (15 acral, 25 mucosal and 41 cutaneous melanoma). With the identification of 1114 mutations spanning 248 genes, we summarized that the mutation spectrum varied significantly by subtypes. Acral melanoma and mucosal melanoma had significantly more CNVs. MYC amplification was one of the most commonly detected CNVs, other frequent CNVs in mucosal melanoma included NBN and KDR, which were associated with the poor survival of melanoma patients. A generally low TMB, with a median of only 5.1 mut/Mb, was observed in three groups including cutaneous melanoma. Additionally, over 50% variants in DNA damage repair pathway were detected in all three subtypes, most of which were HRD related genes. Patients with alterations of HRD related genes had a longer survival time after immunotherapy. This study revealed a molecular profiling of Chinese patients with advanced melanoma, and proposed the high variant rate in DDR pathway as a biomarker of immunotherapy, which might provide therapeutic targets and guidance in making clinical decision for different Chinese melanoma.

Efficacy and safety of anti-PD-1 inhibitor combined with nab-paclitaxel in Chinese patients with refractory melanoma.

PURPOSE: This retrospective study aimed to evaluate the combined effect of anti-PD-1 inhibitor and nanoparticle albumin-bound (nab)-paclitaxel for refractory melanoma among Chinese patients. METHODS: Data from January 2018 to March 2021 were retrospectively collected and analyzed. Sixty-four patients were eligible for analysis from a single Chinese cancer center. RESULTS: The median follow-up was 16.0 months at data cutoff. The objective response rate (ORR) was 29.7%, and the disease control rate (DCR) was 67.2% in all patients. Treatment-naïve patients had significantly higher ORR than pretreated patients (42.9% vs 13.8%, p = 0.011). Cutaneous melanoma patients with NRAS gene mutation benefited more than non-mutated patients (DCR of 100% vs. 54.5%) (p = 0.030). The median progression-free survival (mPFS) of all patients was 5.2 months and the duration of response was 10.8 months. Median duration of disease control was 7.7 months. Prior treatment-naïve patients had significantly longer PFS than those who accepted prior treatments (7.2 vs. 5.1 months, p = 0.024). Patients with abnormally high LDH level had shorter mPFS (3.6 months vs. 6.6 months, p = 0.020). Median overall survival was not reached in this study. Most patients experienced adverse events (AEs), but only 17.2% of patients experienced grade 3 severe AEs. The most common AEs were alopecia (89.1%), neutropenia (18.8%), pruritus (15.6%), and arthralgia (14.1%). Some patients had immune related AEs (irAEs). No grade 4 or 5 AEs were observed. Patients with ≥ 3 AEs or with irAEs had longer mPFS (p < 0.05). CONCLUSION: Nab-paclitaxel combined with PD-1 antibody is a well-tolerated and effective regimen for Chinese patients with refractory melanoma.

Adjuvant PD-1 inhibitor versus high-dose interferon α-2b for Chinese patients with cutaneous and acral melanoma: A retrospective cohort analysis.

The clinical efficacy of PD-1 inhibitors as an adjuvant treatment for Asian melanoma patients has not yet been determined. This retrospective study analyzed the clinical data of 90 Chinese patients with completely resected, stage III cutaneous or acral melanoma who received either adjuvant PD-1 inhibitor or high-dose interferon α-2b (HDI). Anti-PD-1 treatment resulted in significantly longer RFS and DMFS than HDI in cutaneous melanoma patients, with hazard ratios (HRs) (anti-PD-1 versus HDI) of 0.402 (95% CI, 0.183-0.886) and 0.324 (95%CI, 0.122 to 0.861) for RFS and DMFS, respectively. However, adjuvant anti-PD-1 treatment had no advantage over HDI in acral melanoma patients with HRs (anti-PD-1 versus HDI) of 1.204 (95% CI, 0.521 to 2.781) and 1.968(95% CI, 0.744-5.209) for RFS and DMFS, respectively. Adjuvant anti-PD-1 treatment yielded a significantly better prognosis than HDI in Chinese patients with stage IIIB/C cutaneous melanoma, but a significant difference was not observed in those with acral melanoma.

SOX2 promotes resistance of melanoma with PD-L1 high expression to T-cell-mediated cytotoxicity that can be reversed by SAHA.

BACKGROUND: Immune checkpoint inhibitors (ICIs) induce better tumor regression in melanoma with programmed cell death 1 ligand 1 (PD-L1) high expression, but there has been an upsurge of failed responses. In this study, we aimed to explore the additional mechanisms possibly accounting for ICIs resistance and interventional strategies to overcome the resistance in melanoma with PD-L1 high expression. METHODS: Melanoma xenografts and cytotoxicity assays were used to investigate function of SOX2 in regulating antitumor immunity. The activity of the janus kinase-signal transducer and activator of transcriptions (JAK-STAT) pathway was investigated by western blots, quantitative PCR and luciferase assay. Epigenetic compounds library screen was employed to identify inhibitors that could decrease SOX2 level. The effect of histone deacetylase inhibitor SAHA in antitumor immunity alone or in combination with immunotherapy was also determined in vitro and in vivo. Prognostic impact of SOX2 was analyzed using transcriptional profiles and clinical data download from the Gene Expression Omnibus and The Cancer Genome Atlas repository. RESULTS: We uncovered a role of SOX2 in attenuating the sensitivity of melanoma cells to CD8+ T-cell killing. Mechanistically, SOX2 inhibited phosphatases suppressor of cytokine signaling 3 (SOCS3) and protein tyrosine phosphatase non-receptor type 1 (PTPN1) transcription, induced duration activation of the JAK-STAT pathway and thereby overexpression of interferon stimulated genes resistance signature (ISG.RS). By targeting the SOX2-JAK-STAT signaling, SAHA promoted the antitumor efficacy of IFNγ or anti-PD-1 in vitro and in vivo. Moreover, SOX2 was an independent prognostic factor for poor survival and resistant to anti-PD-1 therapy in melanoma with PD-L1 high expression. CONCLUSIONS: Our data unveiled an additional function of SOX2 causing immune evasion of CD8+ T-cell killing through alleviating the JAK-STAT pathway and ISG.RS expression. We also provided a rationale to explore a novel combination of ICIs with SAHA clinically, especially in melanoma with PD-L1 and SOX2 high expression.

Time-varying pattern of recurrence risk for localized melanoma in China.

BACKGROUND: Acral and mucosal melanomas are rarely seen in Caucasians but common in China. There are limited data on the recurrence characteristics for these patients. This study aimed to identify the recurrence pattern for localized melanoma in China, especially acral and mucosal subtypes. METHODS: Patients with localized melanoma who underwent radical resection between January 1999 and December 2014 in southern China were retrospectively reviewed. Survival and annual recurrence hazard were analyzed by Kaplan-Meier method and hazard function, respectively. RESULTS: Totally, 1012 patients were included (acral melanoma 400; chronic sun-induced damage (CSD)/non-CSD melanoma 314; mucosal melanoma 298). Recurrence was recorded in 808 patients (localized 14.1%; regional 29.6%, and distant 56.3%). Mucosal melanoma had local and M1c stage recurrence more frequently than cutaneous melanoma, but less frequent regional node relapse. There was no difference in recurrent site distribution between acral and CSD/non-CSD melanoma. The annual recurrence hazard curve for the entire cohort showed a double-peaked pattern with the first major peak in the second year after surgery and the second peak near the seventh year. Mucosal melanoma had a higher recurrence risk than cutaneous melanoma. Acral melanoma had a lower flat recurrence peak than CSD/non-CSD melanoma. Tumor thickness > 4.0 mm, ulceration, positive regional nodes, and wound infection were associated with a higher recurrence risk in cutaneous melanoma. Adjuvant therapy reduced the recurrence risk of cutaneous melanoma but not of mucosal melanoma. CONCLUSIONS: This is a large cohort about the rule of recurrence risk in acral and mucosal melanoma and will provide an initial framework for development of surveillance and adjuvant strategy for Chinese melanoma patients.