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biotechbio

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biotechbio
·há 28 dias·discuss
Not true, there is a growing class of "operator" VCs that both fund and help run early stage companies.
biotechbio
·há 28 dias·discuss
The obvious other factors in this reframing of equity compensation effectively render it a useless take.

The disparity in expected value calculation is due to assuming you can predict the future after joining a company, which is obviously not true. If you can always tell a company is going to succeed after 1 year of working there, you should leave, as you are clearly destined to be the most successful venture capitalist in history

Not to be overly negative, I think this perspective is somewhat misleading as it lets one rationalize valuing startup equity as anything more than a gamble. Which it is, and always has been. Sometimes gambles work out though.
biotechbio
·há 30 dias·discuss
This post is a little long winded. At times I agreed, and others I felt the author was doing a little too much hand-wringing on what-is-mine vs. what-is-the-AI's.

The opportunity is and always has been the possibility of accelerating work. Honestly, if something works (I mean genuinely, actually works) I don't care at all about what craftsmanship or insight went into its creation.

We value these things because they have become correlated with quality. We now have the opportunity to decouple these things; maybe something that took no effort will be just as good as a painstaking human labor.

The risk is if this doesn't come true. If we let our skills degrade and get ahead of our skis, embracing "slop" that superficially appears to "work", we will eventually pay the price. Financially and culturally, it seems like we are already all-in on the bet that it will work.

I hope it does, I just want to solve the problems I am working on.
biotechbio
·há 5 meses·discuss
+1. From the original post, I found this video to be particularly damning: https://www.youtube.com/watch?v=hksVvXONrIo

Does anyone have an explanation for how something like this passes QC at a company with the resources of Apple? Is this video misrepresenting something?
biotechbio
·há 6 meses·discuss
When you use a microscope to magnify something, the objective (magnifying lens) is literally taking the Fourier transform of the image. The optical system recovers up to a limiting frequency, determining the spatial resolution of the image.
biotechbio
·há 6 meses·discuss
I disagree, in my opinion passing the bar exam is necessary but not nearly sufficient for competently practicing law.

The bar is an imperfect filter. One could study for the exam and pass and still be hugely deficient in ability as an attorney.

I would argue there's no exam that could replace the evaluative and experiential component of 3 years in law school, and accreditation helps enforce at least some standard of quality in the profession. More incompetent lawyers -> more wasteful behavior -> a more bloated and slower legal system -> worse outcomes for everyone.

I think reducing barriers to completing the legal education (part-time programs, lower cost, etc) are better avenues for increasing access.
biotechbio
·há 7 meses·discuss
While cancer is caused by mutations in the genome, these mutations in turn produce the unifying property of cancer: unchecked cell replication.

Most cell types have systems to safely manage replication. Broadly, there are gas pedals (oncogenes) and brakes (tumor suppressors). A classic oncogene is something like RAS, which activates a signaling cascacde and stimulates progression through the cell cycle. A canonical tumor suppressor is something like TP53, the most frequently mutated gene in cancer, which senses various cellular stresses and induces apoptosis or senescence.

Most cancer genomes are more complicated than individual point mutations (SNPs), insertions, or deletions. There are copy number alterations, where you have > or < 2 copies of a genomic region or chromosome, large scale genomic rearrangements, metabolism changes, and extrachromosomal DNA. There is a series on the hallmarks of cancer which is a useful overview [1].

All of the mechanisms that intrinsically regulate cell growth would fall under your "L1 defense". Unfortunately, the idea of reversing somatic point mutations is likely to be a challenging approach to treating cancer given the current state of technology.

First, for the reasons above, cancer is often multifactorial and it would be difficult to identify a single driver that would effectively cure the disease if corrected. Second, we don't have currently delivery or in vivo base editing technology that is sensitive or specific enough to cure cancer by this means. There are gene therapies like zolgensma[2] which act to introduce a working episomal (not replacing the damaged version in the genome) copy of the gene responsible for SMA. There are also in vivo cell therapies like CAR T which attempt to introduce a transgene that encodes for an anti-cancer effector on T cells. These sorts of approaches may give some insight into the current state of art in this field.

Edit: also I should note that the genes involved in DNA repair (PARP, BRACA1/2, MSH2, MLH1, etc) are frequently mutated in cancers and therapeutically relevant. There are drugs that target them, sometimes rather successfully (e.g. PARP inhibitors). But the mechanisms of action for these therapies are more complicated than outright correcting the somatic mutations.

1. https://aacrjournals.org/cancerdiscovery/article/12/1/31/675... 2. https://en.wikipedia.org/wiki/Onasemnogene_abeparvovec
biotechbio
·há 12 meses·discuss
https://en.wikipedia.org/wiki/Clonal_hematopoiesis
biotechbio
·há 12 meses·discuss
Some thoughts on this as someone working on circulating-tumor DNA for the last decade or so:

- Sure, cancer can develop years before diagnosis. Pre-cancerous clones harboring somatic mutations can exist for decades before transformation into malignant disease.

- The eternal challenge in ctDNA is achieving a "useful" sensitivity and specificity. For example, imagine you take some of your blood, extract the DNA floating in the plasma, hybrid-capture enrich for DNA in cancer driver genes, sequence super deep, call variants, do some filtering to remove noise and whatnot, and then you find some low allelic fraction mutations in TP53. What can you do about this? I don't know. Many of us have background somatic mutations speckled throughout our body as we age. Over age ~50, most of us are liable to have some kind of pre-cancerous clones in the esophagus, prostate, or blood (due to CHIP). Many of the popular MCED tests (e.g. Grail's Galleri) use signals other than mutations (e.g. methylation status) to improve this sensitivity / specificity profile, but I'm not convinced its actually good enough to be useful at the population level.

- The cost-effectiveness of most follow on screening is not viable for the given sensitivity-specificity profile of MCED assays (Grail would disagree). To achieve this, we would need things like downstream screening to be drastically cheaper, or possibly a tiered non-invasive screening strategy with increasing specificity to be viable (e.g. Harbinger Health).
biotechbio
·ano passado·discuss
This is a pretty cool study with some interesting findings! Cancer immunotherapy has a long history but has become very prominent in recent years. (Fun fact: the senior author on this paper, Ed Engleman, co-founded of one of the first cancer cell therapy companies, Dendreon, in the early 90s). However, the success of immunotherapies has been limited by the immune-exclusionary nature of the tumor microenvironment (TME). Why some tumors are immune-hot and others are immune-cold is still a very open research question.

In this study, the authors demonstrate pretty convincingly that erythropoietin (EPO, a hormone that stimulates red blood cell production in the bone marrow) reduces the recruitment of tumor-cell-killing T cells to the TME. It does this by acting on tumor macrophages, another type of immune cell, and changes the state of these cells to facilitate accumulation of immunosuppressive cells.

They work out the mechanism largely through mouse models and associative analysis in human tissue samples, but I thought it was interesting that this finding aligns with the clinical observation that cancer patients who receive recombinant EPO for treatment of anemia frequently experience tumor progression.

After reading this, I am going back to check out EPO expression in old datasets that I worked with haha.
biotechbio
·ano passado·discuss
I've had an excellent experience with Cursor: https://www.cursor.com/en

I used VSCode as my default IDE so the switch was very natural.

I am working on machine learning in bio, and many of the tools, methods, and data structures are very domain specific. Even so, the agent feature is good enough that for most tasks, I can describe the functionality I want and it gets me 80% of the way there. I pay $20 a month for Cursor and it has quickly become the last subscription I would cancel.
biotechbio
·ano passado·discuss
Strongly disagree. My son is going to be born into a county with an active measles outbreak caused entirely by misinformation and stupidity. We can’t vaccinate until 6 months. Absolutely preventable. Zero arguments against vaccination for measles. Public health is everyone’s problem.
biotechbio
·ano passado·discuss
I am curious about the same thing. I worked as a ML engineer for several years and have a couple of degrees in the field. Skimming over the document, I recognized almost everything but I would not be able to recall many of these topics if asked without context, although at one time I might have been able to.

What are others' general level of recall for this stuff? Am I a charlatan who never was very good at math or is it just expected that you will forget these things in time if you're not using them regularly?
biotechbio
·há 2 anos·discuss
There's a decent amount of cynicism in the comments, which I understand. I think this is a really cool and novel study, though.

Historically, cancer was treated with therapies that are toxic to all cells, relying on the fact that cancer cells divide quickly and are unable to handle stress as well as normal cells (chemotherapy, radiation).

The last couple of decades we've seen many targeted cancer therapies. These drugs generally inhibit the activity of a specific protein that lets the cancer cells grow (e.g. EGFR inhibitors) or prevents the immune system from killing the cancer cells (e.g. PDL1 inhibitors).

This mechanism is way more interesting. The gene BCL6 is usually turned on in immune cells when they are mutating to recognize foreign invaders. This process involves lots of DNA damage and stress, but BCL6 stops the cells from dying and is therefore important for normal immune function. Unfortunately, this makes BCL6 a gene that is often co-opted in cancer cells to help them survive.

The method cleverly exploits the oncogenic function of BCL6 not by inhibiting it, but by turning it into a guide, enabling the delivery of activating machinery to the targets of BCL6 and reversing the inhibitory effects on cell death.

The whole field of targeted degraders, molecular glues, and heterobifunctional molecules is a growing area of interest in cancer research.
biotechbio
·há 3 anos·discuss
It’s fairly common for private companies to have non-transferability clauses for both options and stock.

IANAL, but this sounds pretty standard and I doubt OP will be able to fight the legitimacy of the claim. Re: a forward sale, sounds like it blatantly violates the agreement and would expose OP to some obvious risks. Agreed OP should talk to a lawyer.

Is anyone else surprised by OP’s indignation? Startups are risky, options aren’t a guaranteed payday, exercising is gamble, and liquidity events are regulated for a reason. Sometimes you lose money. Have we forgotten this?
biotechbio
·há 3 anos·discuss
Sure, absence of evidence is not evidence of absence. But these PCAWG results have been discussed to death since they were published, and its pretty sound science.

You could also take the bottom-up approach of asking what DOES cause certain cancers. That's a whole other discussion.

Considering all this, if you still have doubts that "viruses do not cause the majority of cancers", I think you will likely be skeptical about pretty much all of biology.
biotechbio
·há 3 anos·discuss
Sure, a 2020 study from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, looking for viral evidence in thousands of tumor genomes and transcriptomes[0]. Part of a massive, cross-institutional effort.

"Searching large pan-cancer genome and whole-transcriptome datasets enabled the identification of a high percentage of virus-associated cases (16%)".

Far from majority.

[0] https://www.nature.com/articles/s41588-019-0558-9
biotechbio
·há 3 anos·discuss
This is not true. Some cancers are caused by viruses. Many oncogenes were initially discovered in viruses. But the majority of tumors are definitely not caused by viruses.

This was a hypothesis in the field for a number of years, and has been disproven. If you want a good overview of the history of cancer, I recommend “The Emperor of All Maladies” by Siddhartha Mukherjee.
biotechbio
·há 3 anos·discuss
The lifespan of T cells varies from months to years (memory T cells). T cell development begins in the bone marrow and continues in the lymphatic tissue and periphery. During their lifespan, these cells circulate in the body and migrate based on chemical gradients.

What happens when you exercise? Blood pressure increases, blood vessels dilate. I honestly would not be surprised if what these authors observed was just existing T cells in capillary beds being kicked up into circulation, only to adhere and begin to intravasate a couple minutes later.
biotechbio
·há 3 anos·discuss
bioscience phd student. Why is this interesting?

Tl;dr from the article, they used flow cytometry to quantify different cell populations in the blood, and noted that the proportion of CD8+ T cells (cytotoxic, the kind of immune cells that recognize and kill cancer cells, among other things) increases after exercise and returns to baseline 30 min later.

Claiming that this supports the idea that cancer patients could benefit* from exercise is a pretty big overstep of scientific inference.

* = in the immune response to their cancer