Management of lower extremity orthopaedic injuries in epileptic patients: A systematic review

Lower-extremity injuries may occur during seizures. There is a lack of standardized guidelines when diagnosing and planning perioperative care. Databases were systematically screened using predefined search terms. Of the 13 patients included, seven (53.8%) involved bilateral femoral neck fractures. Associated fractures were observed in all cases with surgical intervention performed in eight (61.5%) patients. Eleven patients reported functional outcomes, with over a quarter (three of 11, [27.3%]) endorsing mild range of motion deficits or issues with ambulation. Post-seizure patients may require standardized diagnostic protocols to ensure prompt management with a specialized treatment approach that accommodates the nuances of their condition.

Combining a novel dual RAF/MEK inhibitor with immunomodulation to promote an anti-tumor response

The therapeutic scope of MEK inhibitors (MEKis) is currently limited to use in BRAF mutant melanoma. Therefore, we aim to develop new strategies to extend their usage to MEKi resistant RAS mutant cancers, which represent an unmet clinical need. A strategy we investigated is to balance the positive and negative immunomodulatory effects of MEKis for optimal combination with immunotherapy. In Ras mutant murine lung cancers, CH5126766 (CKI27) is novel due to its ability to inhibit both RAF and MEK, preventing the rebound of ERK that normally results from the relief of negative feedback in the MAPK pathway. We observed that CKI27 increased MHC expression on tumor cells and T cell mediated killing. Yet, CKI27 also decreased T cell proliferation, activation, and cytolytic activity. Implementing a break for T cells to recover with intermittent dosing of CKI27 partially relieved these inhibitory effects. Further combination with co-stimulatory agonist antibodies targeting OX40 and GITR completely alleviated these T cell toxicities and increased combination efficacy with checkpoint blockade antibody anti-CTLA-4. Understanding the immunomodulatory effects of combining CKI27 with immunotherapy will elucidate the mechanism behind their increased efficacy. This will allow us to make more informed decisions in dosing regimens, overcoming resistance, and generating long-term immune responses in current and future clinical trials treating patients with RAS mutant cancers.

Pulsatile MEK inhibition improves anti-tumor immunity and T cell function in Kras mutant lung cancer

KRAS is one of the most commonly identified driver oncogene in non-small cell lung cancer (NSCLC) and is commonly associated with disease refractory to current available modalities of treatment. Targeted therapy to inhibit MEK has shown promising tumor growth control in preclinical models, but is followed by quick rebound of tumor growth. Recently, immune checkpoint blockade has shown clinical activity by dis-inhibiting T cells that are suppressed in the tumor microenvironment. We sought to identify the most effective therapy for the treatment of KRAS mutant NSCLC patients by targeting cancer cells and activating infiltrating immune cells concurrently. We focused on studying the impact of pulsatile MEK inhibition on the immune microenvironment. We found that pulsatile MEK inhibition maintained T cell activation better than continuous treatment ex vivo and in vivo. Treatment with two different MEK inhibitors (selumetinib and trametinib) each resulted in higher CTLA-4 and PD-1 expression in tumor-infiltrating T cells using pulsatile treatment, compared to continuous treatment in Kras mutant lung cancer mice. In addition, the pulsatile schedule showed a superior anti-tumor effect and delayed drug resistance compared to the continuous schedule. Further, combination of pulsatile MEK inhibitor treatment and CTLA-4 blockade resulted in the longest survival of Kras tumor-bearing mice. Similar experiments in immune deficient mice confirmed that this prolonged survival is conferred by adaptive immunity. Our findings set the foundation for a combinatorial therapeutic strategy using pulsatile targeted therapy together with immunotherapy in patients to optimally enhance tumor apoptosis and promote immune response simultaneously.