Autoimmune diseases and immune-checkpoint inhibitors for cancer therapy: review of the literature and personalized risk-based prevention strategy

Patients with cancer and with preexisting active autoimmune diseases (ADs) have been excluded from immunotherapy clinical trials because of concerns for high susceptibility to the development of severe adverse events resulting from exacerbation of their preexisting ADs. However, a growing body of evidence indicates that immune-checkpoint inhibitors (ICIs) may be safe and effective in this patient population. However, baseline corticosteroids and other nonselective immunosuppressants appear to negatively impact drug efficacy, whereas retrospective and case report data suggest that use of specific immunosuppressants may not have the same consequences. Therefore, we propose here a two-step strategy. First, to lower the risk of compromising ICI efficacy before their initiation, nonselective immunosuppressants could be replaced by specific selective immunosuppressant drugs following a short rotation phase. Subsequently, combining ICI with the selective immunosuppressant could prevent exacerbation of the AD. For the most common active ADs encountered in the context of cancer, we propose specific algorithms to optimize ICI therapy. These preventive strategies go beyond current practices and recommendations, and should be practiced in ICI-specialized clinics, as these require multidisciplinary teams with extensive knowledge in the field of clinical immunology and oncology. In addition, we challenge the exclusion from ICI therapy for patients with cancer and active ADs and propose the implementation of an international registry to study such novel strategies in a prospective fashion.

Abstract P2-06-17: A novel interaction of AURKA with MAPK pathway in breast cancer cells as a potential therapeutic target

Background: Aurora A (AURKA) is a mitotic kinase responsible for centrosome segregation and mitotic spindle formation. In normal cells, expression of AURKA is highly regulated and is predominantly restricted to G2/M phases of the cell cycle. Unlike healthy cells, cancer cells overexpress AURKA through all phases of the cell cycle resulting in the acquisition of alternate non-mitotic functions. Little is known about cellular functions regulated by AURKA and its interaction with other signaling molecules. Here, we report a novel interaction between AURKA and the mitogen-activated protein kinase (MAPK) pathway at the level of MEK1 in breast cancer cells. This interaction may serve as a novel target as well as demonstrate by an additive cytotoxic effect of AURKA- and MEK1/2-specific inhibitors against estrogen positive (ER+) and triple negative breast cancer (TNBC) cells.

Results: We show that treatment of ER+ HER2- MCF-7, ER- HER2+ SKBR3 and ER- HER2- BT549 cells with AURKA specific inhibitors alisertib, MK8745 and Aurora A Inhibitor I resulted in over 2-fold increase in relative levels of poMEK1/2 and poERK1/2 compared to untreated controls. The activation of the MAPK pathway was rapid with changes seen within 5 min after treatment with AURKA inhibitors and was sustained for at least 48 hours. Treatment with the pan RAF inhibitor TAK-632 did not diminish alisertib-induced poERK and poMEK1/2. Alternatively, treatment with the MEK1/2 specific inhibitor PD0325901 completely abrogated alisertib-induced phosphorylation of MEK1/2 and ERK1/2. In situ proximity ligation and pull down assays demonstrated AURKA and MEK1/2 direct interaction. In vitro kinase assay showed direct phosphorylation of MEK1 by AURKA. Combined treatment of alisertib and PD0325901 in vitro revealed significant additive cytotoxic effect in MCF-7 and BT549 cells when compared to either agent used alone (p< 0.008 and p<0.011; p <0.04 and p<0.028) with early trend toward significance in survival in a BT549 xenograft breast cancer in vivo model.

Conclusions: Our data shows a novel AURKA-MEK1 interaction in breast cancer cells. In depth in vivo analysis is ongoing. The results reveal a promising new strategy for the treatment TNBC patients using a combination of AURKA and MEK1/2 inhibitors.

Citation Format: Gandhi S, Gil M, Khoury T, Takabe K, Puzanov I, Gelman I, D'Assoro A, Opyrchal M. A novel interaction of AURKA with MAPK pathway in breast cancer cells as a potential therapeutic target [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-06-17.

Managing toxicities associated with immune checkpoint inhibitors: consensus recommendations from the Society for Immunotherapy of Cancer (SITC) Toxicity Management Working Group

Cancer immunotherapy has transformed the treatment of cancer. However, increasing use of immune-based therapies, including the widely used class of agents known as immune checkpoint inhibitors, has exposed a discrete group of immune-related adverse events (irAEs). Many of these are driven by the same immunologic mechanisms responsible for the drugs' therapeutic effects, namely blockade of inhibitory mechanisms that suppress the immune system and protect body tissues from an unconstrained acute or chronic immune response. Skin, gut, endocrine, lung and musculoskeletal irAEs are relatively common, whereas cardiovascular, hematologic, renal, neurologic and ophthalmologic irAEs occur much less frequently. The majority of irAEs are mild to moderate in severity; however, serious and occasionally life-threatening irAEs are reported in the literature, and treatment-related deaths occur in up to 2% of patients, varying by ICI. Immunotherapy-related irAEs typically have a delayed onset and prolonged duration compared to adverse events from chemotherapy, and effective management depends on early recognition and prompt intervention with immune suppression and/or immunomodulatory strategies. There is an urgent need for multidisciplinary guidance reflecting broad-based perspectives on how to recognize, report and manage organ-specific toxicities until evidence-based data are available to inform clinical decision-making. The Society for Immunotherapy of Cancer (SITC) established a multidisciplinary Toxicity Management Working Group, which met for a full-day workshop to develop recommendations to standardize management of irAEs. Here we present their consensus recommendations on managing toxicities associated with immune checkpoint inhibitor therapy.

Melanoma antigens are biomarkers for ipilimumab response

BACKGROUND

Novel immunotherapy modalities significantly improve survival of patients with metastatic melanoma. However, CTLA-4-blocking monoclonal antibody ipilimumab is effective only in a small proportion of patients. Biomarkers for prediction of treatment response are indispensably needed.

OBJECTIVE

To determine the utility of multimarker detection of circulating melanoma cells as prognostic and pharmacodynamic biomarker in patients with metastatic melanoma treated with ipilimumab.

METHODS

Patients (n = 62) with metastatic melanoma in unresectable stage III or metastatic stage IV treated with ipilimumab were recruited prospectively. The values of four melanoma markers on circulating cells Melan-A, gp100, MAGE-3 and melanoma inhibitory antigen prior to the treatment and within the therapy were compared to the data collected at baseline - after the melanoma surgery.

RESULTS

The immunotherapy pretreatment marker level was found to be prognostic of overall survival; lower levels were linked to longer survival time. Moreover, longitudinal follow-up of melanoma markers in patients treated with ipilimumab correlates with therapy response. A decline of marker levels by >30% at week 6 (in 83% of the responding subjects) to week 9 (in all responders) of ipilimumab administration was associated with response to therapy. Elevation of the tumour markers during the treatment precedes clinical progression and gives an early warning of treatment failure.

CONCLUSION

Melanoma circulating cells hold potential as predictive and pharmacodynamic biomarker of immunotherapy.

Skin toxicity and efficacy of sunitinib and sorafenib in metastatic renal cell carcinoma: a national registry-based study

BACKGROUND

A retrospective, registry-based analysis to assess the outcomes of metastatic renal cell cancer (mRCC) patients treated with sunitinib and sorafenib who developed dermatologic adverse events was performed.

PATIENTS AND METHODS

Data on mRCC patients treated with sunitinib or sorafenib were obtained from the Czech Clinical Registry of Renal Cell Cancer Patients. Outcomes of patients who developed hand-foot syndrome (HFS) of any grade and/or grade 3/4 rash during the treatment were compared with patients without HFS and no, mild, or moderate rash.

RESULTS

The cohort included 705 patients treated with sunitinib and 365 patients treated with sorafenib. For sunitinib, the median overall survival (OS) was 43.0 months versus 31.0 months (P = 0.027) and median progression-free survival (PFS) 20.8 months versus 11.1 months (P = 0.007) for patients with versus without dermatologic toxicity, respectively. For sorafenib, the median OS and PFS were 27.9 and 24.6 months (P = 0.244), and 12.2 and 8.8 months (P = 0.050), respectively. In multivariable Cox regression, the skin toxicity was significantly associated with longer OS in the sunitinib cohort.

CONCLUSION

The presence of skin toxicity is associated with improved OS and PFS in patients with mRCC treated with sunitinib.

[BRAF mutation: a novel approach in targeted melanoma therapy]

The incidence of malignant melanoma is increasing worldwide, despite our best efforts in prevention and early detection. The locally advanced disease may be treated surgically with good results, however, metastatic melanoma is considered to be one of the most therapeutically challenging malignancies. The increasing knowledge of molecular changes in melanoma may change this picture. Malignant melanoma is not a singular, homogeneous disease but rather a mixture of subtypes characterized by specific mutations. Tumors with C-KIT mutation respond to therapy with C-KIT kinase inhibitor imatinib and the ones characterized by BRAF mutations respond to BRAF kinase inhibitor vemurafenib. Vemurafenib was approved by US FDA in 2011 and EMA in 2012 for therapy of patients with advanced melanoma, harboring mutation in BRAFV600E gene. Ipilimumab, an antibody to cytotoxic T-lymphocyte antigen 4 (CTLA-4), was registered in 2011 by both US FDA and European Medicines Agency for treatment of metastatic melanoma. This therapy promotes the anti-tumor T-cell activity by blocking a CTLA-4 antigen, a key negative regulator of immune response.

Hand–foot syndrome (HFS) as a potential biomarker of efficacy in patients (pts) with metastatic renal cell carcinoma (mRCC) treated with sunitinib (SU)

320

Background: HFS and related skin toxicities are common side effects of tyrosine kinase inhibitors such as SU, a multitargeted inhibitor of VEGF and PDGF receptors plus other receptor tyrosine kinases. In a randomized phase III trial of treatment-naïve mRCC pts, SU showed superior progression-free survival (PFS) and objective response rate (ORR) over interferon-alfa, with a median PFS of 11 mo and median overall survival (OS) of 26.4 mo, establishing SU as a reference standard of care (Motzer et al, 2009). In this retrospective analysis, correlations between SU-associated HFS and efficacy endpoints were investigated in mRCC pts from 5 clinical trials in the first- and second-line treatment settings.

Methods: Analyses included pooled data from 770 pts who received single-agent SU as 50 mg/d on a 4-week-on/2-week-off schedule (n=544; 71%) or 37.5 mg continuous once-daily dosing (n=226; 29%). Median PFS and OS were estimated by Kaplan–Meier methods and compared between pts with vs without HFS using a log-rank test. ORR was compared by Pearson's chi-square test. Tumor response was assessed by investigators and adverse events were recorded regularly. Multivariate and time-dependent covariate analyses were performed.

Results: Of 770 pts, 179 (23%) developed any-grade HFS, compared with 591 (77%) who did not. Most instances of HFS (63%) initially occurred during the first 3 treatment cycles. Pts who developed HFS had significantly better ORR (55.6% vs. 32.7%), PFS (14.3 vs. 8.3 mo), and OS (38.3 vs. 18.9 mo) than pts who did not develop HFS (p<0.0001). In a multivariate analysis, SU-associated HFS remained a significant independent predictor of both PFS and OS (and of OS by time-dependent covariate analysis).

Conclusions: In mRCC pts, SU-associated HFS was significantly and independently associated with improved clinical outcomes. Overall, pts who did not develop HFS still had substantial benefit from SU. However, the presence of HFS identified a subset of pts that manifested highly favorable efficacy results with SU. These findings suggest that development of HFS may serve as a predictive biomarker of SU efficacy, although prospective validation is warranted.

[Table: see text]