Natural products isolated from marine mollusks and sponges can reverse multidrug resistance in cancer cells

Oceans are a treasure trove of naturally produced chemical compounds with impressive and varied biological activity. One class of these compounds, the lamellarins, has some members that are cytotoxic, while others are able to reverse multidrug resistance in certain cancer cells. These lamellarins (see below structure) act by inhibiting the so-called P-glycoprotein, which enhances transport of anticancer agents out of cancer cells, thus rendering the cells multidrug resistant.

Now researchers lead by Professor Rob Capon, have set out to determine the structures of a variety of lamellarins and correlate them to the activity of the compounds. As they report in Chemistry—An Asian Journal, the activity is not determined by the core structure of the compounds but rather depends on the exact nature of pendant groups adorning the periphery of the molecule. Those compounds in which many hydroxy (OH) groups had been replaced with methoxy (OCH₃) were able to reverse multidrug resistance in human colon cancer cells, while those featuring a large number of hydroxy groups showed higher cytotoxic activity.

Natural products such as the lamellarins are often valued for their cytotoxic properties for use as anticancer drugs. Capon, however, comments, "Our investigation reaffirms the view that non-cytotoxic natural products can exhibit valuable biological properties that allude to both an ecological advantage and a pharmacological potential....

Ref : http://onlinelibrary.wiley.com/doi/10.1002/asia.201101049/abstract;jsessionid=D96AD6C21A9E2EAF7D966C0743768A2A.d01t03

Metformin may protect against liver cancer

In continuation of my update on Metformin

Metformin may protect against liver cancer: Metformin, a widely used, well-tolerated drug prescribed for patients with diabetes, may protect against liver cancer, according to a new study.

Immunotherapy and Chemotherapy Regimen May Prolong Survival in Advanced Cancers

In continuation of my update on interleukin and retinoic acid

Cancer patients who receive a combination of low-dose interleukin-2 and retinoic acid after conventional therapy seem to live longer than those who don't get the combination. 

Retinoic acid is derived from vitamin A. Interleukin-2, a compound that fortifies the immune system, is approved at high doses to treat "metastatic" melanoma and kidney cancer. Metastatic means that a cancer has spread.

The study showed that "these biological compounds may work at low doses. Bigger doses are not always better," said lead author Dr. Francesco Recchia, director of the oncology department at Civilian Hospital in Avezzano, Italy.

Recchia stumbled upon the possibility of using low-dose interleukin-2 (IL-2) when he switched a patient with metastatic melanoma who didn't tolerate high doses to a lower dose, and the patient had an extended response to the therapy.

This study involved 500 patients who had already responded well to chemotherapy. They had a variety of cancers, including ovarian, lung, colon, stomach, kidney, melanoma, breast and pancreatic.

Immunotherapy and Chemotherapy Regimen May Prolong Survival in Advanced Cancers

Paclitaxel drug slows damage and symptoms in (Alzheimer's disease) animal model

A compound,  epothilone D (EpoD) that previously progressed to Phase II clinical trials for cancer treatment slows neurological damage and improves brain function in an animal model of Alzheimer's disease, according to a new study.  Compound is effective in preventing further neurological damage and improving cognitive performance in a mouse model of Alzheimer's disease (AD). The results establish how the drug might be used in early-stage AD patients......

Potential Alzheimer's disease drug slows damage and symptoms in animal model

Rigosertib drug shows promise against advanced pancreatic cancer

Researchers from University of Colorado, lead by Antonio Jimeno, have found that, a new drug, Rigosertib,  allows pancreatic cancer cells to rush through replication - and then stops them cold, killing them in in the middle of a step called M phase. Healthy cells that don't rush are unharmed.

Data from a phase I clinical trial of patients with advanced pancreatic cancer and additional solid tumors recently published in the journal Clinical Cancer Research shows the strategy has promise. While the goal of any phase I trial is to establish the dosage that best balances effectiveness against side effects, 11 of the 19 patients treated achieved stable disease, which lasted for a median of 113 days.

"Really, the drug takes one of cancer's greatest strengths and turns it into a weakness," says Wells Messersmith, MD, co-leader of the Developmental Therapeutics Program at the University of Colorado Cancer Center and the clinical trial's national principal investigator.

Instead of going with the flow of the natural cell cycle, cancer cells amplify two signals - PLK1 and PI3K - which allows them to blast through the cell cycle and divide much more quickly. In the process, they break this step of the natural cell cycle, known as the G1 regulatory mechanism, and thus depend on the kick of PLK1 and P13K to push at a frenzied pace through replication...

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Notch inhibitor appears to treat breast cancer....

In a novel therapeutic approach to treating breast cancer, Loyola University Medical Center researchers are reporting positive results from a clinical trial of a drug that targets tumor stem cells. A pilot study at Loyola found that an experimental drug known as a "notch inhibitor" appears to block this process by turning off key genes. Prior to surgery, the patients received one of two commonly used drugs, tamoxifen or letrozole. These drugs work by blocking estrogen stimulation of breast cancer cells. In addition to tamoxifen or letrozole, patients also received the experimental notch-inhibitor drug, MK-0752 (see structure).

 "The notch inhibitor appears to be doing what it is intended to do," said Dr. Clodia Osipo....

There were minimal side effects from either the notch inhibitor or the estrogen-blocking drugs. One patient experienced puffy eyes and coughing and four patients experienced facial acne. No patients experienced diarrhea or surgical complications.

Ref : Loyola Medicine News Release

Synta's ganetespib shows potent in vitro and in vivo activity against multiple breast cancer types

Synta researchers  have reported that, Ganetespib (structure)  shows potent in vitro and in vivo activity against multiple types of breast cancer including HER2-positive, ER/PR positive, triple-negative, and inflammatory breast cancer. 

"These results demonstrating that ganetespib potently inhibits key signaling pathways involved in the growth and proliferation of multiple forms of breast cancer are encouraging, and supportive of the results presented earlier at this meeting showing single-agent, anti-tumor activity in patients with breast cancer who have progressed on or failed to respond to multiple prior therapies," said Vojo Vukovic, M.D., Ph.D., Chief Medical Officer, Synta. 

Researchers conclude that, the combined preclinical and clinical results create a strong rationale for advancing ganetespib development in both HER2-positive and triple-negative breast cancer.

More : http://phoenix.corporate-ir.net/phoenix.zhtml?c=147988&p=irol-newsArticle&ID=1638540&highlight=

HSC NEWS - Bat plant could give some cancers a devil of a time

In a new study published this month in the Journal of the American Chemical Society, researchers with The University of Texas Health Science Center at San Antonio have pinpointed the cancer-fighting potential in the bat plant, or Tacca chantrieri......

HSC NEWS - Bat plant could give some cancers a devil of a time

Cisplatin anti-cancer drug binds pervasively to RNA....

In continuation of my update on Cisplatin.....

An anti-cancer drug used extensively in chemotherapy binds pervasively to RNA -- up to 20-fold more than it does to DNA, a surprise finding that suggests new targeting approaches might be useful, according to University of Oregon researchers, lead by Victoria J. DeRose

Ref : http://uonews.uoregon.edu/archive/news-release/2011/11/cancer-drug-cisplatin-found-bind-glue-cellular-rna

Old drugs find new target for treating brain tumor

In continuation of erlotinib ................................

Old drugs find new target for treating brain tumor

Positive results from combination drug trial for late-stage ovarian cancer

In continuation of my update on  carboplatin

Researchers from IU Medical Sciences Program-Bloomington  and Indiana University Melvin, have found that, an experimental two-drug combination (decitabine & carboplatin) for treating late-stage ovarian cancer continues to produce strong results, leading its Indiana University researchers to actively pursue the next step, conducting a larger clinical trial to test the therapy and to see how it compares with existing treatments for ovarian cancer.

The researchers have been investigating the addition of decitabine, which is marketed as Dacogen in the United States, because they suspect it reactivates tumor suppression genes that are turned off in ovarian cancer cells and improves cells' susceptibility to anti-cancer drugs like carboplatin.

"The science associated with the trial is novel and exciting and could have impact in the future," she said.....

More...

Taxoxifen combined with dasatinib reverses chemo-resistance in breast cancer cells

Researchers from Thomas Jefferson University Hospita,  found that taxoxifen combined with dasatinib, a protein-tyrosine kinase inhibitor, reverses the chemo-resistance caused by cancer-associated fibroblasts in the surrounding tissue by normalizing glucose intake and reducing mitochondrial oxidative stress, the process that fuels the cancer cells. 

In this study, researchers sought to better understand drug resistance by looking at the metabolic basis in an ER (+) cell line and cancer-associated fibroblasts.  Researchers claim that the  resistance to chemotherapeutic agents is a metabolic and stromal phenomenal  and the drug combination had an "antioxidant effect" in these types of cancer cells.  

Researchers showed that ER (+) cancer cells alone responded to tamoxifen but when co-cultured with human fibroblasts had little to no effect. Similarly, dasatinib, a chemotherapy drug used to treat leukemia patients who can no longer benefit from other medications, had no effect on fibroblasts alone or cancer cells. Together, however, the drugs prevented the cancer cells co-cultured with the fibroblasts from using high-energy nutrients from the fibroblasts. Researchers conclude that, 

"The drugs have no effect when they are used alone-it's in unison when they effectively kill the cancer cells in the presence of fibroblasts and combination resulted in nearly 80 percent cell death" 

Ref: http://www.jeffersonhospital.org/News/leukemia-drug-reverses-tamoxifen-resistance-in-breast-cancer-cells.aspx

When Having the Blues is a Good Thing: Blueberries & Cancer Prevention

In continuation of my up date on the usefulness of blue berries.

Now researchers from the Department of Nutrition Sciences at the University of Alabama at Birmingham, lead by Laura Newton have come up with another interesting finding about blue berries, i.e., as little as a cup a day can help prevent cell damage linked to cancer.

As per the claim by the researchers, free radicals, atoms that contain an odd number of electrons and are highly reactive, can cause cellular damage, one of the factors in the development of cancer; many believe a diet filled with fruits and vegetables may help reduce the risk. 

Lead researcher says

"Studies suggest that antioxidants may help prevent the free-radical damage associated with cancer"

Researchers add that, Blueberries also are rich in vitamin C, which helps the immune system and can help the body to absorb iron. "Vitamin C also helps to keep blood vessels firm, offering protection from bruising. Blueberry juice and other products may be nutritious but often contain less fiber than the whole fruit, and added sugar or corn syrup may decrease their nutritional value. Consuming fresh, raw blueberries provides the most benefits; the average serving size of raw blueberries is one cup, which contains about 80 calories...

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New anti-cancer agents show promise for treating aggressive breast cancers

New anti-cancer agents show promise for treating aggressive breast cancers

More....

New breast cancer drug: Promising results of PI3K inhibitor study

 
New breast cancer drug: Promising results of PI3K inhibitor study

New anti-cancer drugs plus chemo for breast cancer shows promise: Study

 New anti-cancer drugs plus chemo for breast cancer shows promise: Study...

ABT-737

  

                                                        


Docetaxel

Sulforaphane-rich foods safe and effective for preventing cancer

In continuation of my update on the benefits of broccoli and  sulforaphane............

Sulforaphane-rich foods safe and effective for preventing cancer

Strawberries for prevention of esophageal cancer: Study

In continuation of my update on benefits of strawberries.....
Strawberries for prevention of esophageal cancer: Study

Vismodegib is an effective treatment for patients with basal cell carcinomas

 Vismodegib :


Vismodegib is an effective treatment for patients with basal cell carcinomas

Tautomycetin Antibiotic Offers Potential for Anti-Cancer Activity.....

Tautomycetin-antibiotic((1R*,2S*)-16-Ethyl-3,7-dihydroxy-1, 2,6,10,12-pentamethyl-5,14-dioxo- 15,17-octadecadienyl 2,5-dihydro-β-hydroxy-4-methyl-2,5-dioxo-3-furanpro panoic acid estersee structure) known for its immunosuppressive functions could also point the way to the development of new anti-cancer agents, researchers at the Indiana University School of Medicine have reported. 

Study determined that the compound, tautomycetin, targets an enzyme called SHP2, which plays an important role in cell activities such as proliferation and differentiation. Interestingly, SHP2 mutations are also known to cause several types of leukemia and solid tumors.

The finding is encouraging because SHP2 is a member of a large family of enzymes called protein tyrosine phosphotases (PTPs), which are important in the signaling processes that control all essential cellular functions. Dysregulation of PTP activity has been linked to several human diseases, including cancer, diabetes, and immune dysfunctions. But their makeup has made it difficult to find potential drugs to act on them.

Authors conclude that,  the  research will serve as a foundation for the development of therapeutic agents for a large family of protein tyrosine phosphotase targets…..

Sijiu Liu, Zhihong Yu et.al.,