What are Chk1 and Chk2?

Function. Checkpoint kinases (Chks) are protein kinases that are involved in cell cycle control. Two checkpoint kinase subtypes have been identified, Chk1 and Chk2. Chk1 is a central component of genome surveillance pathways and is a key regulator of the cell cycle and cell survival.

What is the hardest breast cancer to treat?

What is triple-negative breast cancer? Triple-negative breast cancer is that which tests negative for three receptors: estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2). It is also the least common form of breast cancer and the hardest to treat.

Is TNBC the most aggressive breast cancer?

Triple-negative breast cancer is considered to be more aggressive and have a poorer prognosis than other types of breast cancer, mainly because there are fewer targeted medicines that treat triple-negative breast cancer.

How is Chk1 activated?

It is well recognized that Chk1 is activated upon phosphorylation at two conserved sites, serine-317 and serine-345 [28, 46, 72]. Although phosphorylation at these two sites is indispensable for the function of Chk1, it remains elusive as to how exactly the phosphorylation activates Chk1 [45].

Is Chk1 a tumor suppressor?

Further, emerging evidence suggests that Chk1 does not appear to be a tumor suppressor; instead, it promotes tumor growth and may contribute to anticancer therapy resistance.

Which type of breast cancer has the best prognosis?

Pure mucinous ductal carcinoma carries a better prognosis than more common types of IDCs. Papillary Carcinoma – This is a very good prognosis breast cancer that primarily occur in women over the age of 60.

What are the odds of surviving breast cancer?

The overall 5-year relative survival rate for breast cancer is 90%. This means 90 out of 100 women are alive 5 years after they’ve been diagnosed with breast cancer. The 10-year breast cancer relative survival rate is 84% (84 out of 100 women are alive after 10 years).

What are two possible outcomes of checkpoint kinase activation?

Upon activation, Chk1 phosphorylates a variety of substrate proteins, resulting in the activation of DNA damage checkpoints, cell cycle arrest, DNA repair, and/or cell death. Chk1 and its related signaling may be an effective therapeutic target in diseases such as cancer.

Can you live 20 years with metastatic breast cancer?

What is the prognosis? While there is no cure for metastatic breast cancer, there are treatments that slow the cancer, extending the patient’s life while also improving the quality of life, Henry says. Many patients now live 10 years or more after a metastatic diagnosis.

How does Chk1 play a role in cancer cells?

In normal cells, p53 induces G1 arrest in response to DNA damage, whereas tumour cells that are often p53-deficient are defective in G1 arrest; therefore, cancer cells, unlike normal cells, rely mainly on S or G2 checkpoints that are mediated by CHK1 ( Chen et al, 2006 ).

What is the significance of Chk1 in BC?

This study investigated the clinicopathological significance of phosphorylated CHK1 (pCHK1) protein in BC. pCHK1 protein expression was assessed using immunohistochemistry in a large, well-characterized annotated series of early-stage primary operable invasive BC prepared as tissue microarray ( n =1200).

Which is the best drug target for Chk1?

Currently, CHK1 represents one of the most attractive and potential target for anticancer drug development directed against the DDR network ( Dai and Grant, 2010 ).

How is pchk1 related to survival in BC?

In ER-negative and triple-negative subgroups, nuclear pCHK1 predicted shorter survival in patients who received cyclophosphamide, methotrexate and 5-florouracil chemotherapy. Our data suggest that pCHK1 may have prognostic and predictive significance in BC. Subcellular localisation of pCHK1 protein is related to its function.