The Testing Evidence for Using Fenbendazole for Treating Colorectal Cancer

Executive Summary

  • This article covers the evidence I could find for Fenbendazole as a treatment for Colorectal Cancer.

Article Summary

Studies demonstrate that Fenbendazole is effective against cancer, we then cover how Fenbendazole works against cancer by explaining the mechanisms of action, and then the impacts of Fenbendazole on cancer.

Introduction

This article provides an overview covering the evidence for Fenbendazole and related drugs versus Colorectal Cancer.

Many articles on this website cover the evidence for the benefits of Fenbendazole for cancer. But the question of which specific cancers Fenbendazole has been proven effective is a constant source of questions.

The most common Benzimidazoles are Fenbendazole, Mebendazole and Albendazole. In our analysis, we include research for all three drugs together in articles as they are very similar to one another and it improves the ability to tie together different studies. You may see the following terms/acronyms used.

  • FZ or FBZ means Fenbendazole
  • MBZ means Mebendazole
  • AZ means Albendazole

Cancer Type #10: Colorectal Cancer

The following quote is from the article Anti-cancer effects of fenbendazole on 5 − fluorouracil-resistant colorectal cancer cells.

The following quote lists drugs readers likely will not recognized. However, they are drugs that are very similar to Fenbendazole and are called “Benzimidazole anthelmintic agents.”

There are many studies on this class of drug – far more than studies on just Fenbendazole. And these multiple different drugs are often referred to in the same study.

Benzimidazole inhibited the proliferation of HCT116 cells [22] and induced apoptosis via activated JNK in HCT116 and SW480 cells [23]. Flubendazole induced mitotic catastrophe with increased cyclin B1 and caspase-3 − PARP pathway [24]. It has an anti-migratory effect by inhibiting the expression of nuclear factor kappa-light-chain-enhancer of activated B cells p65 in CRC cells derived from primary tumor and lymph node metastasis [25]. In addition, Williamson et al. [26] showed that mebendazole combined with non-steroidal anti-inflammatory drugs reduced tumor initiation by decreasing c-Myc and increasing apoptosis in an ApcMin / + mouse model of familial adenomatous polyposis.

Although fenbendazole enhance the cytotoxicity of radiation or docetaxel and increased the anti-cancer effects of radiation against mammary tumors [27], only a few studies evaluated at the anti-cancer effects of benzimidazole against metastatic or resistant cancers [28 − 30]. Albendazole effectively inhibited paclitaxel- and doxorubicin-resistant lung cancer cells [31] and thereby reduced multidrug resistance. Nonetheless, the role of benzimidazole in resistant CRC has yet to be reported. Therefore, we aimed to evaluate the effects and underlying mechanisms of fenbendazole in SNU-C5 / 5 − FUR cells as compared with wild type SNU-C5 cells in order to identify therapeutic strategies to overcome resistance to 5 − FU.

The following quote is from the article Screening of Benzimidazole-Based Anthelmintics and Their Enantiomers as Repurposed Drug Candidates in Cancer Therapy.

Several benzimidazole-based anthelmintic compounds have been recognized to exert antitumor effects with a marked cancer cell-specific selectivity. In the present study, we investigated the effects of a large series of benzimidazole-based anthelmintics and their enantiomers on the viability of different tumor cells, including paraganglioma, and pancreatic and colorectal cancer cell lines. Six benzimidazoles, namely flubendazole, parbendazole, oxibendazole, mebendazole, albendazole and fenbendazole, emerged as the most active compounds, with consistent antiproliferative effects across the tested cancer cell lines and IC50 values all in the low micromolar range, or even in the nanomolar range. Interestingly, in silico evaluation of their physicochemical, pharmacokinetics and medicinal chemistry properties predicted the potential of these six compounds as candidates for repurposing as oral drugs for cancer in humans.

Adding up the Studies of Fenbendazole Versus Cancer

There are many studies of Fenbendazole, Mebendazole, Albendazole, and other Benzimidazole derivatives versus cancer.

Due to the success of these studies and the information published in the study publications, the specific mechanisms by which these Benzimidazole-based Anthelmintics work against cancer are at this point well understood. There has not been a study published for every cancer type using one of the Benzimidazole derivatives. There are a very large number of different cancer types and limited funding for this type of research.

How Many Major Cancer Types Are There Studies For?

When I completed my analysis, I found 18 different types of cancer types which demonstrated effectiveness versus cancer. In many cases, these different cancer types had multiple cancer studies testing the different Benzimidazole derivatives.

Cancer centers do not apply the large body of published studies on the effectiveness of Benzimidazole derivatives to include as part of their treatment offerings. This is true even though Fenbendazole has been demonstrated to improve chemotherapy outcomes.

To understand the mechanisms by which Benzimidazole derivatives work against cancer, see the following few examples. To see all of the known mechanisms that I have compiled from all of the studies see the article on the mechanisms listed below.

The Multiple Mechanisms by Which Fenbendazole Works Against Cancer

There are many ways in which Fenbendazole works against cancer including.

  • Reducing metastasis
  • Increase autophagy
  • Increase cancer cell death or apoptosis
  • and much more

This topic is covered in the article By How Many Different Mechanisms Does Fenbendazole Fight Cancer?