Favourable outcome of coronavirus disease 2019 in a patient with anaplastic lymphoma kinase-positive non-small-cell lung cancer receiving alectinib

Serine-arginine protein kinases and their targets in viral infection and their inhibition

Accumulating evidence has consolidated the interaction between viral infection and host alternative splicing. Serine-arginine (SR) proteins are a class of highly conserved splicing factors critical for the spliceosome maturation, alternative splicing and RNA metabolism. Serine-arginine protein kinases (SRPKs) are important kinases that specifically phosphorylate SR proteins to regulate their distribution and activities in the central pre-mRNA splicing and other cellular processes. In addition to the predominant SR proteins, other cytoplasmic proteins containing a serine-arginine repeat domain, including viral proteins, have been identified as substrates of SRPKs. Viral infection triggers a myriad of cellular events in the host and it is therefore not surprising that viruses explore SRPKs-mediated phosphorylation as an important regulatory node in virus-host interactions. In this review, we briefly summarize the regulation and biological function of SRPKs, highlighting their involvement in the infection process of several viruses, such as viral replication, transcription and capsid assembly. In addition, we review the structure-function relationships of currently available inhibitors of SRPKs and discuss their putative use as antivirals against well-characterized viruses or newly emerging viruses. We also highlight the viral proteins and cellular substrates targeted by SRPKs as potential antiviral therapeutic candidates.

Host protein kinases required for SARS-CoV-2 nucleocapsid phosphorylation and viral replication

Multiple coronaviruses have emerged independently in the past 20 years that cause lethal human diseases. Although vaccine development targeting these viruses has been accelerated substantially, there remain patients requiring treatment who cannot be vaccinated or who experience breakthrough infections. Understanding the common host factors necessary for the life cycles of coronaviruses may reveal conserved therapeutic targets. Here, we used the known substrate specificities of mammalian protein kinases to deconvolute the sequence of phosphorylation events mediated by three host protein kinase families (SRPK, GSK-3, and CK1) that coordinately phosphorylate a cluster of serine and threonine residues in the viral N protein, which is required for viral replication. We also showed that loss or inhibition of SRPK1/2, which we propose initiates the N protein phosphorylation cascade, compromised the viral replication cycle. Because these phosphorylation sites are highly conserved across coronaviruses, inhibitors of these protein kinases not only may have therapeutic potential against COVID-19 but also may be broadly useful against coronavirus-mediated diseases.

Alectinib continuation during COVID 19 'antiviral' treatment: Risk or benefit?

INTRODUCTION

Serious Acute Respiratory Syndrome Coronavirus 2 (SARSCoV2) has led to COVID 19 pandemic a year ago and it has not been globally taken under control yet. COVID 19 tends to have poorer prognosis in cancer patients. Additionally, we have no well-established guidelines for management of these patients during pandemic, in terms of treatment of 'cancer' and treatment of 'COVID 19'. Tyrosine kinase inhibitors (TKIs) are given without any break in cancer patients to have better survival outcomes in daily routine. However, there is no well-established data to continue or delay ALK inhibitors in lung cancer patients infected with SARS-CoV2. Concomittant use of ALK inhibitors and COVID 19 antiviral treatment is a dilemma because of the lack of data in this area.

CASE REPORT

A 47-year old female metastatic ALK positive nonsquamous cell lung cancer patient on alectinib, a second generation ALK inhibitor was diagnosed with symptomatic COVID 19. She was given favipiravir for COVID 19 while continuing alectinib.Management and outcome: The patient continued alectinib during COVID 19 antiviral treatment without any break. She tolerated 'concomittant' alectinib & favipiravir. She had partial remission after three months of alectinib without any dose adjustment despite active COVID 19 medication.

DISCUSSION

To best of our knowledge, this is the first case who continued alectinib without dose adjustment during antiviral COVID-19 medication without clinically worsening. There is limited data about 'concomittant' use of TKIs and antiviral COVID 19 medication in the literature. There are some case reports, but they generally tended to delay or suspend TKIs during COVID 19 antiviral medication. Our case differs from them in terms of continuation of alectinib without any break or additional side effects during favipiravir for symptomatic COVID 19. We consider that our case might contribute to the literature in terms of management of cancer patients on targeted therapy during COVID 19 antiviral treatment. However, clinical trials are needed in this area.