Prostate cancer incidence and survival in relation to prostate cancer as second cancer in relatives

Targeting P21-Activated Kinase-1 for Metastatic Prostate Cancer

Metastatic prostate cancer (mPCa) has limited therapeutic options and a high mortality rate. The p21-activated kinase (PAK) family of proteins is important in cell survival, proliferation, and motility in physiology, and pathologies such as infectious, inflammatory, vascular, and neurological diseases as well as cancers. Group-I PAKs (PAK1, PAK2, and PAK3) are involved in the regulation of actin dynamics and thus are integral for cell morphology, adhesion to the extracellular matrix, and cell motility. They also play prominent roles in cell survival and proliferation. These properties make group-I PAKs a potentially important target for cancer therapy. In contrast to normal prostate and prostatic epithelial cells, group-I PAKs are highly expressed in mPCA and PCa tissue. Importantly, the expression of group-I PAKs is proportional to the Gleason score of the patients. While several compounds have been identified that target group-I PAKs and these are active in cells and mice, and while some inhibitors have entered human trials, as of yet, none have been FDA-approved. Probable reasons for this lack of translation include issues related to selectivity, specificity, stability, and efficacy resulting in side effects and/or lack of efficacy. In the current review, we describe the pathophysiology and current treatment guidelines of PCa, present group-I PAKs as a potential druggable target to treat mPCa patients, and discuss the various ATP-competitive and allosteric inhibitors of PAKs. We also discuss the development and testing of a nanotechnology-based therapeutic formulation of group-I PAK inhibitors and its significant potential advantages as a novel, selective, stable, and efficacious mPCa therapeutic over other PCa therapeutics in the pipeline.

Familial risk associated with lung cancer as a second primary malignancy in first-degree relatives

BACKGROUND

Aggregation of lung cancer (LCa) in family members is well-documented. However, little is known on the familial risk of LCa when first-degree relatives (FDRs, parents or siblings) are diagnosed with LCa as a second primary malignancy (LCa-2). We aimed to investigate whether and to what extent a family history of LCa-2 was associated with an increased LCa risk.

METHODS

In this Swedish national cohort we identified 127,865 individuals who had one FDR affected by LCa as a first primary cancer (LCa-1) and 15,490 individuals who had one FDR affected by LCa-2, respectively. We then estimated relative risk (RR) of LCa using those without cancer family history as reference.

RESULTS

The number of LCa-2 has been increasing annually and rather similarly in men and women in the last decade. Familial RR of LCa was 1.96 (95%, 1.85-2.07) for LCa-1 family history and 1.89 for LCa-2 (1.62-2.21). Risk was especially high when FDR was diagnosed with early-onset LCa-2 and when siblings were affected by LCa-2. The RR was 1.53 (1.10-2.12) when LCa-2 in FDR was diagnosed within 26 months after first primary cancer, and it increased to 2.16 (1.62-2.90) when LCa-2 was diagnosed between 74 to 154 months. Higher risk was observed for first primary cancer of the ovary (4.45, 1.85-10.7), nervous system (3.49, 1.45-8.38), upper aerodigestive tract (2.83, 1.78-4.49) and cervix (2.55, 1.41-4.61), and for non-Hodgkin lymphoma (3.13, 1.57-6.27).

CONCLUSIONS

LCa risk is associated with diagnosis of LCa-2 in FDR to a similar degree as LCa-1 in FDRs.

The Expression of Proto-Oncogene ETS-Related Gene (ERG) Plays a Central Role in the Oncogenic Mechanism Involved in the Development and Progression of Prostate Cancer

The ETS-related gene (ERG) is proto-oncogene that is classified as a member of the ETS transcription factor family, which has been found to be consistently overexpressed in about half of the patients with clinically significant prostate cancer (PCa). The overexpression of ERG can mostly be attributed to the fusion of the ERG and transmembrane serine protease 2 (TMPRSS2) genes, and this fusion is estimated to represent about 85% of all gene fusions observed in prostate cancer. Clinically, individuals with ERG gene fusion are mostly documented to have advanced tumor stages, increased mortality, and higher rates of metastasis in non-surgical cohorts. In the current review, we elucidate ERG’s molecular interaction with downstream genes and the pathways associated with PCa. Studies have documented that ERG plays a central role in PCa progression due to its ability to enhance tumor growth by promoting inflammatory and angiogenic responses. ERG has also been implicated in the epithelial–mesenchymal transition (EMT) in PCa cells, which increases the ability of cancer cells to metastasize. In vivo, research has demonstrated that higher levels of ERG expression are involved with nuclear pleomorphism that prompts hyperplasia and the loss of cell polarity.